-common-obj-y += migration.o migration-tcp.o
+common-obj-y += migration.o tcp.o
common-obj-y += vmstate.o
common-obj-y += qemu-file.o qemu-file-unix.o qemu-file-stdio.o
-common-obj-$(CONFIG_RDMA) += migration-rdma.o
common-obj-y += xbzrle.o
-common-obj-$(CONFIG_POSIX) += migration-exec.o migration-unix.o migration-fd.o
+common-obj-$(CONFIG_RDMA) += rdma.o
+common-obj-$(CONFIG_POSIX) += exec.o unix.o fd.o
-common-obj-y += block-migration.o
+common-obj-y += block.o
+++ /dev/null
-/*
- * QEMU live block migration
- *
- * Copyright IBM, Corp. 2009
- *
- * Authors:
- * Liran Schour <lirans@il.ibm.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
-
-#include "qemu-common.h"
-#include "block/block.h"
-#include "qemu/error-report.h"
-#include "qemu/main-loop.h"
-#include "hw/hw.h"
-#include "qemu/queue.h"
-#include "qemu/timer.h"
-#include "migration/block.h"
-#include "migration/migration.h"
-#include "sysemu/blockdev.h"
-#include <assert.h>
-
-#define BLOCK_SIZE (1 << 20)
-#define BDRV_SECTORS_PER_DIRTY_CHUNK (BLOCK_SIZE >> BDRV_SECTOR_BITS)
-
-#define BLK_MIG_FLAG_DEVICE_BLOCK 0x01
-#define BLK_MIG_FLAG_EOS 0x02
-#define BLK_MIG_FLAG_PROGRESS 0x04
-#define BLK_MIG_FLAG_ZERO_BLOCK 0x08
-
-#define MAX_IS_ALLOCATED_SEARCH 65536
-
-//#define DEBUG_BLK_MIGRATION
-
-#ifdef DEBUG_BLK_MIGRATION
-#define DPRINTF(fmt, ...) \
- do { printf("blk_migration: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
- do { } while (0)
-#endif
-
-typedef struct BlkMigDevState {
- /* Written during setup phase. Can be read without a lock. */
- BlockDriverState *bs;
- int shared_base;
- int64_t total_sectors;
- QSIMPLEQ_ENTRY(BlkMigDevState) entry;
-
- /* Only used by migration thread. Does not need a lock. */
- int bulk_completed;
- int64_t cur_sector;
- int64_t cur_dirty;
-
- /* Protected by block migration lock. */
- unsigned long *aio_bitmap;
- int64_t completed_sectors;
- BdrvDirtyBitmap *dirty_bitmap;
- Error *blocker;
-} BlkMigDevState;
-
-typedef struct BlkMigBlock {
- /* Only used by migration thread. */
- uint8_t *buf;
- BlkMigDevState *bmds;
- int64_t sector;
- int nr_sectors;
- struct iovec iov;
- QEMUIOVector qiov;
- BlockAIOCB *aiocb;
-
- /* Protected by block migration lock. */
- int ret;
- QSIMPLEQ_ENTRY(BlkMigBlock) entry;
-} BlkMigBlock;
-
-typedef struct BlkMigState {
- /* Written during setup phase. Can be read without a lock. */
- int blk_enable;
- int shared_base;
- QSIMPLEQ_HEAD(bmds_list, BlkMigDevState) bmds_list;
- int64_t total_sector_sum;
- bool zero_blocks;
-
- /* Protected by lock. */
- QSIMPLEQ_HEAD(blk_list, BlkMigBlock) blk_list;
- int submitted;
- int read_done;
-
- /* Only used by migration thread. Does not need a lock. */
- int transferred;
- int prev_progress;
- int bulk_completed;
-
- /* Lock must be taken _inside_ the iothread lock. */
- QemuMutex lock;
-} BlkMigState;
-
-static BlkMigState block_mig_state;
-
-static void blk_mig_lock(void)
-{
- qemu_mutex_lock(&block_mig_state.lock);
-}
-
-static void blk_mig_unlock(void)
-{
- qemu_mutex_unlock(&block_mig_state.lock);
-}
-
-/* Must run outside of the iothread lock during the bulk phase,
- * or the VM will stall.
- */
-
-static void blk_send(QEMUFile *f, BlkMigBlock * blk)
-{
- int len;
- uint64_t flags = BLK_MIG_FLAG_DEVICE_BLOCK;
-
- if (block_mig_state.zero_blocks &&
- buffer_is_zero(blk->buf, BLOCK_SIZE)) {
- flags |= BLK_MIG_FLAG_ZERO_BLOCK;
- }
-
- /* sector number and flags */
- qemu_put_be64(f, (blk->sector << BDRV_SECTOR_BITS)
- | flags);
-
- /* device name */
- len = strlen(bdrv_get_device_name(blk->bmds->bs));
- qemu_put_byte(f, len);
- qemu_put_buffer(f, (uint8_t *)bdrv_get_device_name(blk->bmds->bs), len);
-
- /* if a block is zero we need to flush here since the network
- * bandwidth is now a lot higher than the storage device bandwidth.
- * thus if we queue zero blocks we slow down the migration */
- if (flags & BLK_MIG_FLAG_ZERO_BLOCK) {
- qemu_fflush(f);
- return;
- }
-
- qemu_put_buffer(f, blk->buf, BLOCK_SIZE);
-}
-
-int blk_mig_active(void)
-{
- return !QSIMPLEQ_EMPTY(&block_mig_state.bmds_list);
-}
-
-uint64_t blk_mig_bytes_transferred(void)
-{
- BlkMigDevState *bmds;
- uint64_t sum = 0;
-
- blk_mig_lock();
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- sum += bmds->completed_sectors;
- }
- blk_mig_unlock();
- return sum << BDRV_SECTOR_BITS;
-}
-
-uint64_t blk_mig_bytes_remaining(void)
-{
- return blk_mig_bytes_total() - blk_mig_bytes_transferred();
-}
-
-uint64_t blk_mig_bytes_total(void)
-{
- BlkMigDevState *bmds;
- uint64_t sum = 0;
-
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- sum += bmds->total_sectors;
- }
- return sum << BDRV_SECTOR_BITS;
-}
-
-
-/* Called with migration lock held. */
-
-static int bmds_aio_inflight(BlkMigDevState *bmds, int64_t sector)
-{
- int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK;
-
- if (sector < bdrv_nb_sectors(bmds->bs)) {
- return !!(bmds->aio_bitmap[chunk / (sizeof(unsigned long) * 8)] &
- (1UL << (chunk % (sizeof(unsigned long) * 8))));
- } else {
- return 0;
- }
-}
-
-/* Called with migration lock held. */
-
-static void bmds_set_aio_inflight(BlkMigDevState *bmds, int64_t sector_num,
- int nb_sectors, int set)
-{
- int64_t start, end;
- unsigned long val, idx, bit;
-
- start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK;
- end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK;
-
- for (; start <= end; start++) {
- idx = start / (sizeof(unsigned long) * 8);
- bit = start % (sizeof(unsigned long) * 8);
- val = bmds->aio_bitmap[idx];
- if (set) {
- val |= 1UL << bit;
- } else {
- val &= ~(1UL << bit);
- }
- bmds->aio_bitmap[idx] = val;
- }
-}
-
-static void alloc_aio_bitmap(BlkMigDevState *bmds)
-{
- BlockDriverState *bs = bmds->bs;
- int64_t bitmap_size;
-
- bitmap_size = bdrv_nb_sectors(bs) + BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1;
- bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8;
-
- bmds->aio_bitmap = g_malloc0(bitmap_size);
-}
-
-/* Never hold migration lock when yielding to the main loop! */
-
-static void blk_mig_read_cb(void *opaque, int ret)
-{
- BlkMigBlock *blk = opaque;
-
- blk_mig_lock();
- blk->ret = ret;
-
- QSIMPLEQ_INSERT_TAIL(&block_mig_state.blk_list, blk, entry);
- bmds_set_aio_inflight(blk->bmds, blk->sector, blk->nr_sectors, 0);
-
- block_mig_state.submitted--;
- block_mig_state.read_done++;
- assert(block_mig_state.submitted >= 0);
- blk_mig_unlock();
-}
-
-/* Called with no lock taken. */
-
-static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds)
-{
- int64_t total_sectors = bmds->total_sectors;
- int64_t cur_sector = bmds->cur_sector;
- BlockDriverState *bs = bmds->bs;
- BlkMigBlock *blk;
- int nr_sectors;
-
- if (bmds->shared_base) {
- qemu_mutex_lock_iothread();
- while (cur_sector < total_sectors &&
- !bdrv_is_allocated(bs, cur_sector, MAX_IS_ALLOCATED_SEARCH,
- &nr_sectors)) {
- cur_sector += nr_sectors;
- }
- qemu_mutex_unlock_iothread();
- }
-
- if (cur_sector >= total_sectors) {
- bmds->cur_sector = bmds->completed_sectors = total_sectors;
- return 1;
- }
-
- bmds->completed_sectors = cur_sector;
-
- cur_sector &= ~((int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK - 1);
-
- /* we are going to transfer a full block even if it is not allocated */
- nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
-
- if (total_sectors - cur_sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
- nr_sectors = total_sectors - cur_sector;
- }
-
- blk = g_new(BlkMigBlock, 1);
- blk->buf = g_malloc(BLOCK_SIZE);
- blk->bmds = bmds;
- blk->sector = cur_sector;
- blk->nr_sectors = nr_sectors;
-
- blk->iov.iov_base = blk->buf;
- blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
- qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
-
- blk_mig_lock();
- block_mig_state.submitted++;
- blk_mig_unlock();
-
- qemu_mutex_lock_iothread();
- blk->aiocb = bdrv_aio_readv(bs, cur_sector, &blk->qiov,
- nr_sectors, blk_mig_read_cb, blk);
-
- bdrv_reset_dirty(bs, cur_sector, nr_sectors);
- qemu_mutex_unlock_iothread();
-
- bmds->cur_sector = cur_sector + nr_sectors;
- return (bmds->cur_sector >= total_sectors);
-}
-
-/* Called with iothread lock taken. */
-
-static int set_dirty_tracking(void)
-{
- BlkMigDevState *bmds;
- int ret;
-
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- bmds->dirty_bitmap = bdrv_create_dirty_bitmap(bmds->bs, BLOCK_SIZE,
- NULL);
- if (!bmds->dirty_bitmap) {
- ret = -errno;
- goto fail;
- }
- }
- return 0;
-
-fail:
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- if (bmds->dirty_bitmap) {
- bdrv_release_dirty_bitmap(bmds->bs, bmds->dirty_bitmap);
- }
- }
- return ret;
-}
-
-static void unset_dirty_tracking(void)
-{
- BlkMigDevState *bmds;
-
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- bdrv_release_dirty_bitmap(bmds->bs, bmds->dirty_bitmap);
- }
-}
-
-static void init_blk_migration(QEMUFile *f)
-{
- BlockDriverState *bs;
- BlkMigDevState *bmds;
- int64_t sectors;
-
- block_mig_state.submitted = 0;
- block_mig_state.read_done = 0;
- block_mig_state.transferred = 0;
- block_mig_state.total_sector_sum = 0;
- block_mig_state.prev_progress = -1;
- block_mig_state.bulk_completed = 0;
- block_mig_state.zero_blocks = migrate_zero_blocks();
-
- for (bs = bdrv_next(NULL); bs; bs = bdrv_next(bs)) {
- if (bdrv_is_read_only(bs)) {
- continue;
- }
-
- sectors = bdrv_nb_sectors(bs);
- if (sectors <= 0) {
- return;
- }
-
- bmds = g_new0(BlkMigDevState, 1);
- bmds->bs = bs;
- bmds->bulk_completed = 0;
- bmds->total_sectors = sectors;
- bmds->completed_sectors = 0;
- bmds->shared_base = block_mig_state.shared_base;
- alloc_aio_bitmap(bmds);
- error_setg(&bmds->blocker, "block device is in use by migration");
- bdrv_op_block_all(bs, bmds->blocker);
- bdrv_ref(bs);
-
- block_mig_state.total_sector_sum += sectors;
-
- if (bmds->shared_base) {
- DPRINTF("Start migration for %s with shared base image\n",
- bdrv_get_device_name(bs));
- } else {
- DPRINTF("Start full migration for %s\n", bdrv_get_device_name(bs));
- }
-
- QSIMPLEQ_INSERT_TAIL(&block_mig_state.bmds_list, bmds, entry);
- }
-}
-
-/* Called with no lock taken. */
-
-static int blk_mig_save_bulked_block(QEMUFile *f)
-{
- int64_t completed_sector_sum = 0;
- BlkMigDevState *bmds;
- int progress;
- int ret = 0;
-
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- if (bmds->bulk_completed == 0) {
- if (mig_save_device_bulk(f, bmds) == 1) {
- /* completed bulk section for this device */
- bmds->bulk_completed = 1;
- }
- completed_sector_sum += bmds->completed_sectors;
- ret = 1;
- break;
- } else {
- completed_sector_sum += bmds->completed_sectors;
- }
- }
-
- if (block_mig_state.total_sector_sum != 0) {
- progress = completed_sector_sum * 100 /
- block_mig_state.total_sector_sum;
- } else {
- progress = 100;
- }
- if (progress != block_mig_state.prev_progress) {
- block_mig_state.prev_progress = progress;
- qemu_put_be64(f, (progress << BDRV_SECTOR_BITS)
- | BLK_MIG_FLAG_PROGRESS);
- DPRINTF("Completed %d %%\r", progress);
- }
-
- return ret;
-}
-
-static void blk_mig_reset_dirty_cursor(void)
-{
- BlkMigDevState *bmds;
-
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- bmds->cur_dirty = 0;
- }
-}
-
-/* Called with iothread lock taken. */
-
-static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
- int is_async)
-{
- BlkMigBlock *blk;
- int64_t total_sectors = bmds->total_sectors;
- int64_t sector;
- int nr_sectors;
- int ret = -EIO;
-
- for (sector = bmds->cur_dirty; sector < bmds->total_sectors;) {
- blk_mig_lock();
- if (bmds_aio_inflight(bmds, sector)) {
- blk_mig_unlock();
- bdrv_drain_all();
- } else {
- blk_mig_unlock();
- }
- if (bdrv_get_dirty(bmds->bs, bmds->dirty_bitmap, sector)) {
-
- if (total_sectors - sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
- nr_sectors = total_sectors - sector;
- } else {
- nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
- }
- blk = g_new(BlkMigBlock, 1);
- blk->buf = g_malloc(BLOCK_SIZE);
- blk->bmds = bmds;
- blk->sector = sector;
- blk->nr_sectors = nr_sectors;
-
- if (is_async) {
- blk->iov.iov_base = blk->buf;
- blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
- qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
-
- blk->aiocb = bdrv_aio_readv(bmds->bs, sector, &blk->qiov,
- nr_sectors, blk_mig_read_cb, blk);
-
- blk_mig_lock();
- block_mig_state.submitted++;
- bmds_set_aio_inflight(bmds, sector, nr_sectors, 1);
- blk_mig_unlock();
- } else {
- ret = bdrv_read(bmds->bs, sector, blk->buf, nr_sectors);
- if (ret < 0) {
- goto error;
- }
- blk_send(f, blk);
-
- g_free(blk->buf);
- g_free(blk);
- }
-
- bdrv_reset_dirty(bmds->bs, sector, nr_sectors);
- break;
- }
- sector += BDRV_SECTORS_PER_DIRTY_CHUNK;
- bmds->cur_dirty = sector;
- }
-
- return (bmds->cur_dirty >= bmds->total_sectors);
-
-error:
- DPRINTF("Error reading sector %" PRId64 "\n", sector);
- g_free(blk->buf);
- g_free(blk);
- return ret;
-}
-
-/* Called with iothread lock taken.
- *
- * return value:
- * 0: too much data for max_downtime
- * 1: few enough data for max_downtime
-*/
-static int blk_mig_save_dirty_block(QEMUFile *f, int is_async)
-{
- BlkMigDevState *bmds;
- int ret = 1;
-
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- ret = mig_save_device_dirty(f, bmds, is_async);
- if (ret <= 0) {
- break;
- }
- }
-
- return ret;
-}
-
-/* Called with no locks taken. */
-
-static int flush_blks(QEMUFile *f)
-{
- BlkMigBlock *blk;
- int ret = 0;
-
- DPRINTF("%s Enter submitted %d read_done %d transferred %d\n",
- __FUNCTION__, block_mig_state.submitted, block_mig_state.read_done,
- block_mig_state.transferred);
-
- blk_mig_lock();
- while ((blk = QSIMPLEQ_FIRST(&block_mig_state.blk_list)) != NULL) {
- if (qemu_file_rate_limit(f)) {
- break;
- }
- if (blk->ret < 0) {
- ret = blk->ret;
- break;
- }
-
- QSIMPLEQ_REMOVE_HEAD(&block_mig_state.blk_list, entry);
- blk_mig_unlock();
- blk_send(f, blk);
- blk_mig_lock();
-
- g_free(blk->buf);
- g_free(blk);
-
- block_mig_state.read_done--;
- block_mig_state.transferred++;
- assert(block_mig_state.read_done >= 0);
- }
- blk_mig_unlock();
-
- DPRINTF("%s Exit submitted %d read_done %d transferred %d\n", __FUNCTION__,
- block_mig_state.submitted, block_mig_state.read_done,
- block_mig_state.transferred);
- return ret;
-}
-
-/* Called with iothread lock taken. */
-
-static int64_t get_remaining_dirty(void)
-{
- BlkMigDevState *bmds;
- int64_t dirty = 0;
-
- QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
- dirty += bdrv_get_dirty_count(bmds->bs, bmds->dirty_bitmap);
- }
-
- return dirty << BDRV_SECTOR_BITS;
-}
-
-/* Called with iothread lock taken. */
-
-static void blk_mig_cleanup(void)
-{
- BlkMigDevState *bmds;
- BlkMigBlock *blk;
-
- bdrv_drain_all();
-
- unset_dirty_tracking();
-
- blk_mig_lock();
- while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) {
- QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry);
- bdrv_op_unblock_all(bmds->bs, bmds->blocker);
- error_free(bmds->blocker);
- bdrv_unref(bmds->bs);
- g_free(bmds->aio_bitmap);
- g_free(bmds);
- }
-
- while ((blk = QSIMPLEQ_FIRST(&block_mig_state.blk_list)) != NULL) {
- QSIMPLEQ_REMOVE_HEAD(&block_mig_state.blk_list, entry);
- g_free(blk->buf);
- g_free(blk);
- }
- blk_mig_unlock();
-}
-
-static void block_migration_cancel(void *opaque)
-{
- blk_mig_cleanup();
-}
-
-static int block_save_setup(QEMUFile *f, void *opaque)
-{
- int ret;
-
- DPRINTF("Enter save live setup submitted %d transferred %d\n",
- block_mig_state.submitted, block_mig_state.transferred);
-
- qemu_mutex_lock_iothread();
- init_blk_migration(f);
-
- /* start track dirty blocks */
- ret = set_dirty_tracking();
-
- if (ret) {
- qemu_mutex_unlock_iothread();
- return ret;
- }
-
- qemu_mutex_unlock_iothread();
-
- ret = flush_blks(f);
- blk_mig_reset_dirty_cursor();
- qemu_put_be64(f, BLK_MIG_FLAG_EOS);
-
- return ret;
-}
-
-static int block_save_iterate(QEMUFile *f, void *opaque)
-{
- int ret;
- int64_t last_ftell = qemu_ftell(f);
- int64_t delta_ftell;
-
- DPRINTF("Enter save live iterate submitted %d transferred %d\n",
- block_mig_state.submitted, block_mig_state.transferred);
-
- ret = flush_blks(f);
- if (ret) {
- return ret;
- }
-
- blk_mig_reset_dirty_cursor();
-
- /* control the rate of transfer */
- blk_mig_lock();
- while ((block_mig_state.submitted +
- block_mig_state.read_done) * BLOCK_SIZE <
- qemu_file_get_rate_limit(f)) {
- blk_mig_unlock();
- if (block_mig_state.bulk_completed == 0) {
- /* first finish the bulk phase */
- if (blk_mig_save_bulked_block(f) == 0) {
- /* finished saving bulk on all devices */
- block_mig_state.bulk_completed = 1;
- }
- ret = 0;
- } else {
- /* Always called with iothread lock taken for
- * simplicity, block_save_complete also calls it.
- */
- qemu_mutex_lock_iothread();
- ret = blk_mig_save_dirty_block(f, 1);
- qemu_mutex_unlock_iothread();
- }
- if (ret < 0) {
- return ret;
- }
- blk_mig_lock();
- if (ret != 0) {
- /* no more dirty blocks */
- break;
- }
- }
- blk_mig_unlock();
-
- ret = flush_blks(f);
- if (ret) {
- return ret;
- }
-
- qemu_put_be64(f, BLK_MIG_FLAG_EOS);
- delta_ftell = qemu_ftell(f) - last_ftell;
- if (delta_ftell > 0) {
- return 1;
- } else if (delta_ftell < 0) {
- return -1;
- } else {
- return 0;
- }
-}
-
-/* Called with iothread lock taken. */
-
-static int block_save_complete(QEMUFile *f, void *opaque)
-{
- int ret;
-
- DPRINTF("Enter save live complete submitted %d transferred %d\n",
- block_mig_state.submitted, block_mig_state.transferred);
-
- ret = flush_blks(f);
- if (ret) {
- return ret;
- }
-
- blk_mig_reset_dirty_cursor();
-
- /* we know for sure that save bulk is completed and
- all async read completed */
- blk_mig_lock();
- assert(block_mig_state.submitted == 0);
- blk_mig_unlock();
-
- do {
- ret = blk_mig_save_dirty_block(f, 0);
- if (ret < 0) {
- return ret;
- }
- } while (ret == 0);
-
- /* report completion */
- qemu_put_be64(f, (100 << BDRV_SECTOR_BITS) | BLK_MIG_FLAG_PROGRESS);
-
- DPRINTF("Block migration completed\n");
-
- qemu_put_be64(f, BLK_MIG_FLAG_EOS);
-
- blk_mig_cleanup();
- return 0;
-}
-
-static uint64_t block_save_pending(QEMUFile *f, void *opaque, uint64_t max_size)
-{
- /* Estimate pending number of bytes to send */
- uint64_t pending;
-
- qemu_mutex_lock_iothread();
- blk_mig_lock();
- pending = get_remaining_dirty() +
- block_mig_state.submitted * BLOCK_SIZE +
- block_mig_state.read_done * BLOCK_SIZE;
-
- /* Report at least one block pending during bulk phase */
- if (pending == 0 && !block_mig_state.bulk_completed) {
- pending = BLOCK_SIZE;
- }
- blk_mig_unlock();
- qemu_mutex_unlock_iothread();
-
- DPRINTF("Enter save live pending %" PRIu64 "\n", pending);
- return pending;
-}
-
-static int block_load(QEMUFile *f, void *opaque, int version_id)
-{
- static int banner_printed;
- int len, flags;
- char device_name[256];
- int64_t addr;
- BlockDriverState *bs, *bs_prev = NULL;
- uint8_t *buf;
- int64_t total_sectors = 0;
- int nr_sectors;
- int ret;
-
- do {
- addr = qemu_get_be64(f);
-
- flags = addr & ~BDRV_SECTOR_MASK;
- addr >>= BDRV_SECTOR_BITS;
-
- if (flags & BLK_MIG_FLAG_DEVICE_BLOCK) {
- /* get device name */
- len = qemu_get_byte(f);
- qemu_get_buffer(f, (uint8_t *)device_name, len);
- device_name[len] = '\0';
-
- bs = bdrv_find(device_name);
- if (!bs) {
- fprintf(stderr, "Error unknown block device %s\n",
- device_name);
- return -EINVAL;
- }
-
- if (bs != bs_prev) {
- bs_prev = bs;
- total_sectors = bdrv_nb_sectors(bs);
- if (total_sectors <= 0) {
- error_report("Error getting length of block device %s",
- device_name);
- return -EINVAL;
- }
- }
-
- if (total_sectors - addr < BDRV_SECTORS_PER_DIRTY_CHUNK) {
- nr_sectors = total_sectors - addr;
- } else {
- nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
- }
-
- if (flags & BLK_MIG_FLAG_ZERO_BLOCK) {
- ret = bdrv_write_zeroes(bs, addr, nr_sectors,
- BDRV_REQ_MAY_UNMAP);
- } else {
- buf = g_malloc(BLOCK_SIZE);
- qemu_get_buffer(f, buf, BLOCK_SIZE);
- ret = bdrv_write(bs, addr, buf, nr_sectors);
- g_free(buf);
- }
-
- if (ret < 0) {
- return ret;
- }
- } else if (flags & BLK_MIG_FLAG_PROGRESS) {
- if (!banner_printed) {
- printf("Receiving block device images\n");
- banner_printed = 1;
- }
- printf("Completed %d %%%c", (int)addr,
- (addr == 100) ? '\n' : '\r');
- fflush(stdout);
- } else if (!(flags & BLK_MIG_FLAG_EOS)) {
- fprintf(stderr, "Unknown block migration flags: %#x\n", flags);
- return -EINVAL;
- }
- ret = qemu_file_get_error(f);
- if (ret != 0) {
- return ret;
- }
- } while (!(flags & BLK_MIG_FLAG_EOS));
-
- return 0;
-}
-
-static void block_set_params(const MigrationParams *params, void *opaque)
-{
- block_mig_state.blk_enable = params->blk;
- block_mig_state.shared_base = params->shared;
-
- /* shared base means that blk_enable = 1 */
- block_mig_state.blk_enable |= params->shared;
-}
-
-static bool block_is_active(void *opaque)
-{
- return block_mig_state.blk_enable == 1;
-}
-
-static SaveVMHandlers savevm_block_handlers = {
- .set_params = block_set_params,
- .save_live_setup = block_save_setup,
- .save_live_iterate = block_save_iterate,
- .save_live_complete = block_save_complete,
- .save_live_pending = block_save_pending,
- .load_state = block_load,
- .cancel = block_migration_cancel,
- .is_active = block_is_active,
-};
-
-void blk_mig_init(void)
-{
- QSIMPLEQ_INIT(&block_mig_state.bmds_list);
- QSIMPLEQ_INIT(&block_mig_state.blk_list);
- qemu_mutex_init(&block_mig_state.lock);
-
- register_savevm_live(NULL, "block", 0, 1, &savevm_block_handlers,
- &block_mig_state);
-}
--- /dev/null
+/*
+ * QEMU live block migration
+ *
+ * Copyright IBM, Corp. 2009
+ *
+ * Authors:
+ * Liran Schour <lirans@il.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
+ */
+
+#include "qemu-common.h"
+#include "block/block.h"
+#include "qemu/error-report.h"
+#include "qemu/main-loop.h"
+#include "hw/hw.h"
+#include "qemu/queue.h"
+#include "qemu/timer.h"
+#include "migration/block.h"
+#include "migration/migration.h"
+#include "sysemu/blockdev.h"
+#include <assert.h>
+
+#define BLOCK_SIZE (1 << 20)
+#define BDRV_SECTORS_PER_DIRTY_CHUNK (BLOCK_SIZE >> BDRV_SECTOR_BITS)
+
+#define BLK_MIG_FLAG_DEVICE_BLOCK 0x01
+#define BLK_MIG_FLAG_EOS 0x02
+#define BLK_MIG_FLAG_PROGRESS 0x04
+#define BLK_MIG_FLAG_ZERO_BLOCK 0x08
+
+#define MAX_IS_ALLOCATED_SEARCH 65536
+
+//#define DEBUG_BLK_MIGRATION
+
+#ifdef DEBUG_BLK_MIGRATION
+#define DPRINTF(fmt, ...) \
+ do { printf("blk_migration: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+typedef struct BlkMigDevState {
+ /* Written during setup phase. Can be read without a lock. */
+ BlockDriverState *bs;
+ int shared_base;
+ int64_t total_sectors;
+ QSIMPLEQ_ENTRY(BlkMigDevState) entry;
+
+ /* Only used by migration thread. Does not need a lock. */
+ int bulk_completed;
+ int64_t cur_sector;
+ int64_t cur_dirty;
+
+ /* Protected by block migration lock. */
+ unsigned long *aio_bitmap;
+ int64_t completed_sectors;
+ BdrvDirtyBitmap *dirty_bitmap;
+ Error *blocker;
+} BlkMigDevState;
+
+typedef struct BlkMigBlock {
+ /* Only used by migration thread. */
+ uint8_t *buf;
+ BlkMigDevState *bmds;
+ int64_t sector;
+ int nr_sectors;
+ struct iovec iov;
+ QEMUIOVector qiov;
+ BlockAIOCB *aiocb;
+
+ /* Protected by block migration lock. */
+ int ret;
+ QSIMPLEQ_ENTRY(BlkMigBlock) entry;
+} BlkMigBlock;
+
+typedef struct BlkMigState {
+ /* Written during setup phase. Can be read without a lock. */
+ int blk_enable;
+ int shared_base;
+ QSIMPLEQ_HEAD(bmds_list, BlkMigDevState) bmds_list;
+ int64_t total_sector_sum;
+ bool zero_blocks;
+
+ /* Protected by lock. */
+ QSIMPLEQ_HEAD(blk_list, BlkMigBlock) blk_list;
+ int submitted;
+ int read_done;
+
+ /* Only used by migration thread. Does not need a lock. */
+ int transferred;
+ int prev_progress;
+ int bulk_completed;
+
+ /* Lock must be taken _inside_ the iothread lock. */
+ QemuMutex lock;
+} BlkMigState;
+
+static BlkMigState block_mig_state;
+
+static void blk_mig_lock(void)
+{
+ qemu_mutex_lock(&block_mig_state.lock);
+}
+
+static void blk_mig_unlock(void)
+{
+ qemu_mutex_unlock(&block_mig_state.lock);
+}
+
+/* Must run outside of the iothread lock during the bulk phase,
+ * or the VM will stall.
+ */
+
+static void blk_send(QEMUFile *f, BlkMigBlock * blk)
+{
+ int len;
+ uint64_t flags = BLK_MIG_FLAG_DEVICE_BLOCK;
+
+ if (block_mig_state.zero_blocks &&
+ buffer_is_zero(blk->buf, BLOCK_SIZE)) {
+ flags |= BLK_MIG_FLAG_ZERO_BLOCK;
+ }
+
+ /* sector number and flags */
+ qemu_put_be64(f, (blk->sector << BDRV_SECTOR_BITS)
+ | flags);
+
+ /* device name */
+ len = strlen(bdrv_get_device_name(blk->bmds->bs));
+ qemu_put_byte(f, len);
+ qemu_put_buffer(f, (uint8_t *)bdrv_get_device_name(blk->bmds->bs), len);
+
+ /* if a block is zero we need to flush here since the network
+ * bandwidth is now a lot higher than the storage device bandwidth.
+ * thus if we queue zero blocks we slow down the migration */
+ if (flags & BLK_MIG_FLAG_ZERO_BLOCK) {
+ qemu_fflush(f);
+ return;
+ }
+
+ qemu_put_buffer(f, blk->buf, BLOCK_SIZE);
+}
+
+int blk_mig_active(void)
+{
+ return !QSIMPLEQ_EMPTY(&block_mig_state.bmds_list);
+}
+
+uint64_t blk_mig_bytes_transferred(void)
+{
+ BlkMigDevState *bmds;
+ uint64_t sum = 0;
+
+ blk_mig_lock();
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ sum += bmds->completed_sectors;
+ }
+ blk_mig_unlock();
+ return sum << BDRV_SECTOR_BITS;
+}
+
+uint64_t blk_mig_bytes_remaining(void)
+{
+ return blk_mig_bytes_total() - blk_mig_bytes_transferred();
+}
+
+uint64_t blk_mig_bytes_total(void)
+{
+ BlkMigDevState *bmds;
+ uint64_t sum = 0;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ sum += bmds->total_sectors;
+ }
+ return sum << BDRV_SECTOR_BITS;
+}
+
+
+/* Called with migration lock held. */
+
+static int bmds_aio_inflight(BlkMigDevState *bmds, int64_t sector)
+{
+ int64_t chunk = sector / (int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK;
+
+ if (sector < bdrv_nb_sectors(bmds->bs)) {
+ return !!(bmds->aio_bitmap[chunk / (sizeof(unsigned long) * 8)] &
+ (1UL << (chunk % (sizeof(unsigned long) * 8))));
+ } else {
+ return 0;
+ }
+}
+
+/* Called with migration lock held. */
+
+static void bmds_set_aio_inflight(BlkMigDevState *bmds, int64_t sector_num,
+ int nb_sectors, int set)
+{
+ int64_t start, end;
+ unsigned long val, idx, bit;
+
+ start = sector_num / BDRV_SECTORS_PER_DIRTY_CHUNK;
+ end = (sector_num + nb_sectors - 1) / BDRV_SECTORS_PER_DIRTY_CHUNK;
+
+ for (; start <= end; start++) {
+ idx = start / (sizeof(unsigned long) * 8);
+ bit = start % (sizeof(unsigned long) * 8);
+ val = bmds->aio_bitmap[idx];
+ if (set) {
+ val |= 1UL << bit;
+ } else {
+ val &= ~(1UL << bit);
+ }
+ bmds->aio_bitmap[idx] = val;
+ }
+}
+
+static void alloc_aio_bitmap(BlkMigDevState *bmds)
+{
+ BlockDriverState *bs = bmds->bs;
+ int64_t bitmap_size;
+
+ bitmap_size = bdrv_nb_sectors(bs) + BDRV_SECTORS_PER_DIRTY_CHUNK * 8 - 1;
+ bitmap_size /= BDRV_SECTORS_PER_DIRTY_CHUNK * 8;
+
+ bmds->aio_bitmap = g_malloc0(bitmap_size);
+}
+
+/* Never hold migration lock when yielding to the main loop! */
+
+static void blk_mig_read_cb(void *opaque, int ret)
+{
+ BlkMigBlock *blk = opaque;
+
+ blk_mig_lock();
+ blk->ret = ret;
+
+ QSIMPLEQ_INSERT_TAIL(&block_mig_state.blk_list, blk, entry);
+ bmds_set_aio_inflight(blk->bmds, blk->sector, blk->nr_sectors, 0);
+
+ block_mig_state.submitted--;
+ block_mig_state.read_done++;
+ assert(block_mig_state.submitted >= 0);
+ blk_mig_unlock();
+}
+
+/* Called with no lock taken. */
+
+static int mig_save_device_bulk(QEMUFile *f, BlkMigDevState *bmds)
+{
+ int64_t total_sectors = bmds->total_sectors;
+ int64_t cur_sector = bmds->cur_sector;
+ BlockDriverState *bs = bmds->bs;
+ BlkMigBlock *blk;
+ int nr_sectors;
+
+ if (bmds->shared_base) {
+ qemu_mutex_lock_iothread();
+ while (cur_sector < total_sectors &&
+ !bdrv_is_allocated(bs, cur_sector, MAX_IS_ALLOCATED_SEARCH,
+ &nr_sectors)) {
+ cur_sector += nr_sectors;
+ }
+ qemu_mutex_unlock_iothread();
+ }
+
+ if (cur_sector >= total_sectors) {
+ bmds->cur_sector = bmds->completed_sectors = total_sectors;
+ return 1;
+ }
+
+ bmds->completed_sectors = cur_sector;
+
+ cur_sector &= ~((int64_t)BDRV_SECTORS_PER_DIRTY_CHUNK - 1);
+
+ /* we are going to transfer a full block even if it is not allocated */
+ nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
+
+ if (total_sectors - cur_sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
+ nr_sectors = total_sectors - cur_sector;
+ }
+
+ blk = g_new(BlkMigBlock, 1);
+ blk->buf = g_malloc(BLOCK_SIZE);
+ blk->bmds = bmds;
+ blk->sector = cur_sector;
+ blk->nr_sectors = nr_sectors;
+
+ blk->iov.iov_base = blk->buf;
+ blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
+ qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
+
+ blk_mig_lock();
+ block_mig_state.submitted++;
+ blk_mig_unlock();
+
+ qemu_mutex_lock_iothread();
+ blk->aiocb = bdrv_aio_readv(bs, cur_sector, &blk->qiov,
+ nr_sectors, blk_mig_read_cb, blk);
+
+ bdrv_reset_dirty(bs, cur_sector, nr_sectors);
+ qemu_mutex_unlock_iothread();
+
+ bmds->cur_sector = cur_sector + nr_sectors;
+ return (bmds->cur_sector >= total_sectors);
+}
+
+/* Called with iothread lock taken. */
+
+static int set_dirty_tracking(void)
+{
+ BlkMigDevState *bmds;
+ int ret;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ bmds->dirty_bitmap = bdrv_create_dirty_bitmap(bmds->bs, BLOCK_SIZE,
+ NULL);
+ if (!bmds->dirty_bitmap) {
+ ret = -errno;
+ goto fail;
+ }
+ }
+ return 0;
+
+fail:
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ if (bmds->dirty_bitmap) {
+ bdrv_release_dirty_bitmap(bmds->bs, bmds->dirty_bitmap);
+ }
+ }
+ return ret;
+}
+
+static void unset_dirty_tracking(void)
+{
+ BlkMigDevState *bmds;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ bdrv_release_dirty_bitmap(bmds->bs, bmds->dirty_bitmap);
+ }
+}
+
+static void init_blk_migration(QEMUFile *f)
+{
+ BlockDriverState *bs;
+ BlkMigDevState *bmds;
+ int64_t sectors;
+
+ block_mig_state.submitted = 0;
+ block_mig_state.read_done = 0;
+ block_mig_state.transferred = 0;
+ block_mig_state.total_sector_sum = 0;
+ block_mig_state.prev_progress = -1;
+ block_mig_state.bulk_completed = 0;
+ block_mig_state.zero_blocks = migrate_zero_blocks();
+
+ for (bs = bdrv_next(NULL); bs; bs = bdrv_next(bs)) {
+ if (bdrv_is_read_only(bs)) {
+ continue;
+ }
+
+ sectors = bdrv_nb_sectors(bs);
+ if (sectors <= 0) {
+ return;
+ }
+
+ bmds = g_new0(BlkMigDevState, 1);
+ bmds->bs = bs;
+ bmds->bulk_completed = 0;
+ bmds->total_sectors = sectors;
+ bmds->completed_sectors = 0;
+ bmds->shared_base = block_mig_state.shared_base;
+ alloc_aio_bitmap(bmds);
+ error_setg(&bmds->blocker, "block device is in use by migration");
+ bdrv_op_block_all(bs, bmds->blocker);
+ bdrv_ref(bs);
+
+ block_mig_state.total_sector_sum += sectors;
+
+ if (bmds->shared_base) {
+ DPRINTF("Start migration for %s with shared base image\n",
+ bdrv_get_device_name(bs));
+ } else {
+ DPRINTF("Start full migration for %s\n", bdrv_get_device_name(bs));
+ }
+
+ QSIMPLEQ_INSERT_TAIL(&block_mig_state.bmds_list, bmds, entry);
+ }
+}
+
+/* Called with no lock taken. */
+
+static int blk_mig_save_bulked_block(QEMUFile *f)
+{
+ int64_t completed_sector_sum = 0;
+ BlkMigDevState *bmds;
+ int progress;
+ int ret = 0;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ if (bmds->bulk_completed == 0) {
+ if (mig_save_device_bulk(f, bmds) == 1) {
+ /* completed bulk section for this device */
+ bmds->bulk_completed = 1;
+ }
+ completed_sector_sum += bmds->completed_sectors;
+ ret = 1;
+ break;
+ } else {
+ completed_sector_sum += bmds->completed_sectors;
+ }
+ }
+
+ if (block_mig_state.total_sector_sum != 0) {
+ progress = completed_sector_sum * 100 /
+ block_mig_state.total_sector_sum;
+ } else {
+ progress = 100;
+ }
+ if (progress != block_mig_state.prev_progress) {
+ block_mig_state.prev_progress = progress;
+ qemu_put_be64(f, (progress << BDRV_SECTOR_BITS)
+ | BLK_MIG_FLAG_PROGRESS);
+ DPRINTF("Completed %d %%\r", progress);
+ }
+
+ return ret;
+}
+
+static void blk_mig_reset_dirty_cursor(void)
+{
+ BlkMigDevState *bmds;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ bmds->cur_dirty = 0;
+ }
+}
+
+/* Called with iothread lock taken. */
+
+static int mig_save_device_dirty(QEMUFile *f, BlkMigDevState *bmds,
+ int is_async)
+{
+ BlkMigBlock *blk;
+ int64_t total_sectors = bmds->total_sectors;
+ int64_t sector;
+ int nr_sectors;
+ int ret = -EIO;
+
+ for (sector = bmds->cur_dirty; sector < bmds->total_sectors;) {
+ blk_mig_lock();
+ if (bmds_aio_inflight(bmds, sector)) {
+ blk_mig_unlock();
+ bdrv_drain_all();
+ } else {
+ blk_mig_unlock();
+ }
+ if (bdrv_get_dirty(bmds->bs, bmds->dirty_bitmap, sector)) {
+
+ if (total_sectors - sector < BDRV_SECTORS_PER_DIRTY_CHUNK) {
+ nr_sectors = total_sectors - sector;
+ } else {
+ nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
+ }
+ blk = g_new(BlkMigBlock, 1);
+ blk->buf = g_malloc(BLOCK_SIZE);
+ blk->bmds = bmds;
+ blk->sector = sector;
+ blk->nr_sectors = nr_sectors;
+
+ if (is_async) {
+ blk->iov.iov_base = blk->buf;
+ blk->iov.iov_len = nr_sectors * BDRV_SECTOR_SIZE;
+ qemu_iovec_init_external(&blk->qiov, &blk->iov, 1);
+
+ blk->aiocb = bdrv_aio_readv(bmds->bs, sector, &blk->qiov,
+ nr_sectors, blk_mig_read_cb, blk);
+
+ blk_mig_lock();
+ block_mig_state.submitted++;
+ bmds_set_aio_inflight(bmds, sector, nr_sectors, 1);
+ blk_mig_unlock();
+ } else {
+ ret = bdrv_read(bmds->bs, sector, blk->buf, nr_sectors);
+ if (ret < 0) {
+ goto error;
+ }
+ blk_send(f, blk);
+
+ g_free(blk->buf);
+ g_free(blk);
+ }
+
+ bdrv_reset_dirty(bmds->bs, sector, nr_sectors);
+ break;
+ }
+ sector += BDRV_SECTORS_PER_DIRTY_CHUNK;
+ bmds->cur_dirty = sector;
+ }
+
+ return (bmds->cur_dirty >= bmds->total_sectors);
+
+error:
+ DPRINTF("Error reading sector %" PRId64 "\n", sector);
+ g_free(blk->buf);
+ g_free(blk);
+ return ret;
+}
+
+/* Called with iothread lock taken.
+ *
+ * return value:
+ * 0: too much data for max_downtime
+ * 1: few enough data for max_downtime
+*/
+static int blk_mig_save_dirty_block(QEMUFile *f, int is_async)
+{
+ BlkMigDevState *bmds;
+ int ret = 1;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ ret = mig_save_device_dirty(f, bmds, is_async);
+ if (ret <= 0) {
+ break;
+ }
+ }
+
+ return ret;
+}
+
+/* Called with no locks taken. */
+
+static int flush_blks(QEMUFile *f)
+{
+ BlkMigBlock *blk;
+ int ret = 0;
+
+ DPRINTF("%s Enter submitted %d read_done %d transferred %d\n",
+ __FUNCTION__, block_mig_state.submitted, block_mig_state.read_done,
+ block_mig_state.transferred);
+
+ blk_mig_lock();
+ while ((blk = QSIMPLEQ_FIRST(&block_mig_state.blk_list)) != NULL) {
+ if (qemu_file_rate_limit(f)) {
+ break;
+ }
+ if (blk->ret < 0) {
+ ret = blk->ret;
+ break;
+ }
+
+ QSIMPLEQ_REMOVE_HEAD(&block_mig_state.blk_list, entry);
+ blk_mig_unlock();
+ blk_send(f, blk);
+ blk_mig_lock();
+
+ g_free(blk->buf);
+ g_free(blk);
+
+ block_mig_state.read_done--;
+ block_mig_state.transferred++;
+ assert(block_mig_state.read_done >= 0);
+ }
+ blk_mig_unlock();
+
+ DPRINTF("%s Exit submitted %d read_done %d transferred %d\n", __FUNCTION__,
+ block_mig_state.submitted, block_mig_state.read_done,
+ block_mig_state.transferred);
+ return ret;
+}
+
+/* Called with iothread lock taken. */
+
+static int64_t get_remaining_dirty(void)
+{
+ BlkMigDevState *bmds;
+ int64_t dirty = 0;
+
+ QSIMPLEQ_FOREACH(bmds, &block_mig_state.bmds_list, entry) {
+ dirty += bdrv_get_dirty_count(bmds->bs, bmds->dirty_bitmap);
+ }
+
+ return dirty << BDRV_SECTOR_BITS;
+}
+
+/* Called with iothread lock taken. */
+
+static void blk_mig_cleanup(void)
+{
+ BlkMigDevState *bmds;
+ BlkMigBlock *blk;
+
+ bdrv_drain_all();
+
+ unset_dirty_tracking();
+
+ blk_mig_lock();
+ while ((bmds = QSIMPLEQ_FIRST(&block_mig_state.bmds_list)) != NULL) {
+ QSIMPLEQ_REMOVE_HEAD(&block_mig_state.bmds_list, entry);
+ bdrv_op_unblock_all(bmds->bs, bmds->blocker);
+ error_free(bmds->blocker);
+ bdrv_unref(bmds->bs);
+ g_free(bmds->aio_bitmap);
+ g_free(bmds);
+ }
+
+ while ((blk = QSIMPLEQ_FIRST(&block_mig_state.blk_list)) != NULL) {
+ QSIMPLEQ_REMOVE_HEAD(&block_mig_state.blk_list, entry);
+ g_free(blk->buf);
+ g_free(blk);
+ }
+ blk_mig_unlock();
+}
+
+static void block_migration_cancel(void *opaque)
+{
+ blk_mig_cleanup();
+}
+
+static int block_save_setup(QEMUFile *f, void *opaque)
+{
+ int ret;
+
+ DPRINTF("Enter save live setup submitted %d transferred %d\n",
+ block_mig_state.submitted, block_mig_state.transferred);
+
+ qemu_mutex_lock_iothread();
+ init_blk_migration(f);
+
+ /* start track dirty blocks */
+ ret = set_dirty_tracking();
+
+ if (ret) {
+ qemu_mutex_unlock_iothread();
+ return ret;
+ }
+
+ qemu_mutex_unlock_iothread();
+
+ ret = flush_blks(f);
+ blk_mig_reset_dirty_cursor();
+ qemu_put_be64(f, BLK_MIG_FLAG_EOS);
+
+ return ret;
+}
+
+static int block_save_iterate(QEMUFile *f, void *opaque)
+{
+ int ret;
+ int64_t last_ftell = qemu_ftell(f);
+ int64_t delta_ftell;
+
+ DPRINTF("Enter save live iterate submitted %d transferred %d\n",
+ block_mig_state.submitted, block_mig_state.transferred);
+
+ ret = flush_blks(f);
+ if (ret) {
+ return ret;
+ }
+
+ blk_mig_reset_dirty_cursor();
+
+ /* control the rate of transfer */
+ blk_mig_lock();
+ while ((block_mig_state.submitted +
+ block_mig_state.read_done) * BLOCK_SIZE <
+ qemu_file_get_rate_limit(f)) {
+ blk_mig_unlock();
+ if (block_mig_state.bulk_completed == 0) {
+ /* first finish the bulk phase */
+ if (blk_mig_save_bulked_block(f) == 0) {
+ /* finished saving bulk on all devices */
+ block_mig_state.bulk_completed = 1;
+ }
+ ret = 0;
+ } else {
+ /* Always called with iothread lock taken for
+ * simplicity, block_save_complete also calls it.
+ */
+ qemu_mutex_lock_iothread();
+ ret = blk_mig_save_dirty_block(f, 1);
+ qemu_mutex_unlock_iothread();
+ }
+ if (ret < 0) {
+ return ret;
+ }
+ blk_mig_lock();
+ if (ret != 0) {
+ /* no more dirty blocks */
+ break;
+ }
+ }
+ blk_mig_unlock();
+
+ ret = flush_blks(f);
+ if (ret) {
+ return ret;
+ }
+
+ qemu_put_be64(f, BLK_MIG_FLAG_EOS);
+ delta_ftell = qemu_ftell(f) - last_ftell;
+ if (delta_ftell > 0) {
+ return 1;
+ } else if (delta_ftell < 0) {
+ return -1;
+ } else {
+ return 0;
+ }
+}
+
+/* Called with iothread lock taken. */
+
+static int block_save_complete(QEMUFile *f, void *opaque)
+{
+ int ret;
+
+ DPRINTF("Enter save live complete submitted %d transferred %d\n",
+ block_mig_state.submitted, block_mig_state.transferred);
+
+ ret = flush_blks(f);
+ if (ret) {
+ return ret;
+ }
+
+ blk_mig_reset_dirty_cursor();
+
+ /* we know for sure that save bulk is completed and
+ all async read completed */
+ blk_mig_lock();
+ assert(block_mig_state.submitted == 0);
+ blk_mig_unlock();
+
+ do {
+ ret = blk_mig_save_dirty_block(f, 0);
+ if (ret < 0) {
+ return ret;
+ }
+ } while (ret == 0);
+
+ /* report completion */
+ qemu_put_be64(f, (100 << BDRV_SECTOR_BITS) | BLK_MIG_FLAG_PROGRESS);
+
+ DPRINTF("Block migration completed\n");
+
+ qemu_put_be64(f, BLK_MIG_FLAG_EOS);
+
+ blk_mig_cleanup();
+ return 0;
+}
+
+static uint64_t block_save_pending(QEMUFile *f, void *opaque, uint64_t max_size)
+{
+ /* Estimate pending number of bytes to send */
+ uint64_t pending;
+
+ qemu_mutex_lock_iothread();
+ blk_mig_lock();
+ pending = get_remaining_dirty() +
+ block_mig_state.submitted * BLOCK_SIZE +
+ block_mig_state.read_done * BLOCK_SIZE;
+
+ /* Report at least one block pending during bulk phase */
+ if (pending == 0 && !block_mig_state.bulk_completed) {
+ pending = BLOCK_SIZE;
+ }
+ blk_mig_unlock();
+ qemu_mutex_unlock_iothread();
+
+ DPRINTF("Enter save live pending %" PRIu64 "\n", pending);
+ return pending;
+}
+
+static int block_load(QEMUFile *f, void *opaque, int version_id)
+{
+ static int banner_printed;
+ int len, flags;
+ char device_name[256];
+ int64_t addr;
+ BlockDriverState *bs, *bs_prev = NULL;
+ uint8_t *buf;
+ int64_t total_sectors = 0;
+ int nr_sectors;
+ int ret;
+
+ do {
+ addr = qemu_get_be64(f);
+
+ flags = addr & ~BDRV_SECTOR_MASK;
+ addr >>= BDRV_SECTOR_BITS;
+
+ if (flags & BLK_MIG_FLAG_DEVICE_BLOCK) {
+ /* get device name */
+ len = qemu_get_byte(f);
+ qemu_get_buffer(f, (uint8_t *)device_name, len);
+ device_name[len] = '\0';
+
+ bs = bdrv_find(device_name);
+ if (!bs) {
+ fprintf(stderr, "Error unknown block device %s\n",
+ device_name);
+ return -EINVAL;
+ }
+
+ if (bs != bs_prev) {
+ bs_prev = bs;
+ total_sectors = bdrv_nb_sectors(bs);
+ if (total_sectors <= 0) {
+ error_report("Error getting length of block device %s",
+ device_name);
+ return -EINVAL;
+ }
+ }
+
+ if (total_sectors - addr < BDRV_SECTORS_PER_DIRTY_CHUNK) {
+ nr_sectors = total_sectors - addr;
+ } else {
+ nr_sectors = BDRV_SECTORS_PER_DIRTY_CHUNK;
+ }
+
+ if (flags & BLK_MIG_FLAG_ZERO_BLOCK) {
+ ret = bdrv_write_zeroes(bs, addr, nr_sectors,
+ BDRV_REQ_MAY_UNMAP);
+ } else {
+ buf = g_malloc(BLOCK_SIZE);
+ qemu_get_buffer(f, buf, BLOCK_SIZE);
+ ret = bdrv_write(bs, addr, buf, nr_sectors);
+ g_free(buf);
+ }
+
+ if (ret < 0) {
+ return ret;
+ }
+ } else if (flags & BLK_MIG_FLAG_PROGRESS) {
+ if (!banner_printed) {
+ printf("Receiving block device images\n");
+ banner_printed = 1;
+ }
+ printf("Completed %d %%%c", (int)addr,
+ (addr == 100) ? '\n' : '\r');
+ fflush(stdout);
+ } else if (!(flags & BLK_MIG_FLAG_EOS)) {
+ fprintf(stderr, "Unknown block migration flags: %#x\n", flags);
+ return -EINVAL;
+ }
+ ret = qemu_file_get_error(f);
+ if (ret != 0) {
+ return ret;
+ }
+ } while (!(flags & BLK_MIG_FLAG_EOS));
+
+ return 0;
+}
+
+static void block_set_params(const MigrationParams *params, void *opaque)
+{
+ block_mig_state.blk_enable = params->blk;
+ block_mig_state.shared_base = params->shared;
+
+ /* shared base means that blk_enable = 1 */
+ block_mig_state.blk_enable |= params->shared;
+}
+
+static bool block_is_active(void *opaque)
+{
+ return block_mig_state.blk_enable == 1;
+}
+
+static SaveVMHandlers savevm_block_handlers = {
+ .set_params = block_set_params,
+ .save_live_setup = block_save_setup,
+ .save_live_iterate = block_save_iterate,
+ .save_live_complete = block_save_complete,
+ .save_live_pending = block_save_pending,
+ .load_state = block_load,
+ .cancel = block_migration_cancel,
+ .is_active = block_is_active,
+};
+
+void blk_mig_init(void)
+{
+ QSIMPLEQ_INIT(&block_mig_state.bmds_list);
+ QSIMPLEQ_INIT(&block_mig_state.blk_list);
+ qemu_mutex_init(&block_mig_state.lock);
+
+ register_savevm_live(NULL, "block", 0, 1, &savevm_block_handlers,
+ &block_mig_state);
+}
--- /dev/null
+/*
+ * QEMU live migration
+ *
+ * Copyright IBM, Corp. 2008
+ * Copyright Dell MessageOne 2008
+ *
+ * Authors:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ * Charles Duffy <charles_duffy@messageone.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
+ */
+
+#include "qemu-common.h"
+#include "qemu/sockets.h"
+#include "qemu/main-loop.h"
+#include "migration/migration.h"
+#include "migration/qemu-file.h"
+#include "block/block.h"
+#include <sys/types.h>
+#include <sys/wait.h>
+
+//#define DEBUG_MIGRATION_EXEC
+
+#ifdef DEBUG_MIGRATION_EXEC
+#define DPRINTF(fmt, ...) \
+ do { printf("migration-exec: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+void exec_start_outgoing_migration(MigrationState *s, const char *command, Error **errp)
+{
+ s->file = qemu_popen_cmd(command, "w");
+ if (s->file == NULL) {
+ error_setg_errno(errp, errno, "failed to popen the migration target");
+ return;
+ }
+
+ migrate_fd_connect(s);
+}
+
+static void exec_accept_incoming_migration(void *opaque)
+{
+ QEMUFile *f = opaque;
+
+ qemu_set_fd_handler2(qemu_get_fd(f), NULL, NULL, NULL, NULL);
+ process_incoming_migration(f);
+}
+
+void exec_start_incoming_migration(const char *command, Error **errp)
+{
+ QEMUFile *f;
+
+ DPRINTF("Attempting to start an incoming migration\n");
+ f = qemu_popen_cmd(command, "r");
+ if(f == NULL) {
+ error_setg_errno(errp, errno, "failed to popen the migration source");
+ return;
+ }
+
+ qemu_set_fd_handler2(qemu_get_fd(f), NULL,
+ exec_accept_incoming_migration, NULL, f);
+}
--- /dev/null
+/*
+ * QEMU live migration via generic fd
+ *
+ * Copyright Red Hat, Inc. 2009
+ *
+ * Authors:
+ * Chris Lalancette <clalance@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
+ */
+
+#include "qemu-common.h"
+#include "qemu/main-loop.h"
+#include "qemu/sockets.h"
+#include "migration/migration.h"
+#include "monitor/monitor.h"
+#include "migration/qemu-file.h"
+#include "block/block.h"
+
+//#define DEBUG_MIGRATION_FD
+
+#ifdef DEBUG_MIGRATION_FD
+#define DPRINTF(fmt, ...) \
+ do { printf("migration-fd: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp)
+{
+ int fd = monitor_get_fd(cur_mon, fdname, errp);
+ if (fd == -1) {
+ return;
+ }
+ s->file = qemu_fdopen(fd, "wb");
+
+ migrate_fd_connect(s);
+}
+
+static void fd_accept_incoming_migration(void *opaque)
+{
+ QEMUFile *f = opaque;
+
+ qemu_set_fd_handler2(qemu_get_fd(f), NULL, NULL, NULL, NULL);
+ process_incoming_migration(f);
+}
+
+void fd_start_incoming_migration(const char *infd, Error **errp)
+{
+ int fd;
+ QEMUFile *f;
+
+ DPRINTF("Attempting to start an incoming migration via fd\n");
+
+ fd = strtol(infd, NULL, 0);
+ f = qemu_fdopen(fd, "rb");
+ if(f == NULL) {
+ error_setg_errno(errp, errno, "failed to open the source descriptor");
+ return;
+ }
+
+ qemu_set_fd_handler2(fd, NULL, fd_accept_incoming_migration, NULL, f);
+}
+++ /dev/null
-/*
- * QEMU live migration
- *
- * Copyright IBM, Corp. 2008
- * Copyright Dell MessageOne 2008
- *
- * Authors:
- * Anthony Liguori <aliguori@us.ibm.com>
- * Charles Duffy <charles_duffy@messageone.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
-
-#include "qemu-common.h"
-#include "qemu/sockets.h"
-#include "qemu/main-loop.h"
-#include "migration/migration.h"
-#include "migration/qemu-file.h"
-#include "block/block.h"
-#include <sys/types.h>
-#include <sys/wait.h>
-
-//#define DEBUG_MIGRATION_EXEC
-
-#ifdef DEBUG_MIGRATION_EXEC
-#define DPRINTF(fmt, ...) \
- do { printf("migration-exec: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
- do { } while (0)
-#endif
-
-void exec_start_outgoing_migration(MigrationState *s, const char *command, Error **errp)
-{
- s->file = qemu_popen_cmd(command, "w");
- if (s->file == NULL) {
- error_setg_errno(errp, errno, "failed to popen the migration target");
- return;
- }
-
- migrate_fd_connect(s);
-}
-
-static void exec_accept_incoming_migration(void *opaque)
-{
- QEMUFile *f = opaque;
-
- qemu_set_fd_handler2(qemu_get_fd(f), NULL, NULL, NULL, NULL);
- process_incoming_migration(f);
-}
-
-void exec_start_incoming_migration(const char *command, Error **errp)
-{
- QEMUFile *f;
-
- DPRINTF("Attempting to start an incoming migration\n");
- f = qemu_popen_cmd(command, "r");
- if(f == NULL) {
- error_setg_errno(errp, errno, "failed to popen the migration source");
- return;
- }
-
- qemu_set_fd_handler2(qemu_get_fd(f), NULL,
- exec_accept_incoming_migration, NULL, f);
-}
+++ /dev/null
-/*
- * QEMU live migration via generic fd
- *
- * Copyright Red Hat, Inc. 2009
- *
- * Authors:
- * Chris Lalancette <clalance@redhat.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
-
-#include "qemu-common.h"
-#include "qemu/main-loop.h"
-#include "qemu/sockets.h"
-#include "migration/migration.h"
-#include "monitor/monitor.h"
-#include "migration/qemu-file.h"
-#include "block/block.h"
-
-//#define DEBUG_MIGRATION_FD
-
-#ifdef DEBUG_MIGRATION_FD
-#define DPRINTF(fmt, ...) \
- do { printf("migration-fd: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
- do { } while (0)
-#endif
-
-void fd_start_outgoing_migration(MigrationState *s, const char *fdname, Error **errp)
-{
- int fd = monitor_get_fd(cur_mon, fdname, errp);
- if (fd == -1) {
- return;
- }
- s->file = qemu_fdopen(fd, "wb");
-
- migrate_fd_connect(s);
-}
-
-static void fd_accept_incoming_migration(void *opaque)
-{
- QEMUFile *f = opaque;
-
- qemu_set_fd_handler2(qemu_get_fd(f), NULL, NULL, NULL, NULL);
- process_incoming_migration(f);
-}
-
-void fd_start_incoming_migration(const char *infd, Error **errp)
-{
- int fd;
- QEMUFile *f;
-
- DPRINTF("Attempting to start an incoming migration via fd\n");
-
- fd = strtol(infd, NULL, 0);
- f = qemu_fdopen(fd, "rb");
- if(f == NULL) {
- error_setg_errno(errp, errno, "failed to open the source descriptor");
- return;
- }
-
- qemu_set_fd_handler2(fd, NULL, fd_accept_incoming_migration, NULL, f);
-}
+++ /dev/null
-/*
- * RDMA protocol and interfaces
- *
- * Copyright IBM, Corp. 2010-2013
- *
- * Authors:
- * Michael R. Hines <mrhines@us.ibm.com>
- * Jiuxing Liu <jl@us.ibm.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2 or
- * later. See the COPYING file in the top-level directory.
- *
- */
-#include "qemu-common.h"
-#include "migration/migration.h"
-#include "migration/qemu-file.h"
-#include "exec/cpu-common.h"
-#include "qemu/main-loop.h"
-#include "qemu/sockets.h"
-#include "qemu/bitmap.h"
-#include "block/coroutine.h"
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/socket.h>
-#include <netdb.h>
-#include <arpa/inet.h>
-#include <string.h>
-#include <rdma/rdma_cma.h>
-
-//#define DEBUG_RDMA
-//#define DEBUG_RDMA_VERBOSE
-//#define DEBUG_RDMA_REALLY_VERBOSE
-
-#ifdef DEBUG_RDMA
-#define DPRINTF(fmt, ...) \
- do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
- do { } while (0)
-#endif
-
-#ifdef DEBUG_RDMA_VERBOSE
-#define DDPRINTF(fmt, ...) \
- do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DDPRINTF(fmt, ...) \
- do { } while (0)
-#endif
-
-#ifdef DEBUG_RDMA_REALLY_VERBOSE
-#define DDDPRINTF(fmt, ...) \
- do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DDDPRINTF(fmt, ...) \
- do { } while (0)
-#endif
-
-/*
- * Print and error on both the Monitor and the Log file.
- */
-#define ERROR(errp, fmt, ...) \
- do { \
- fprintf(stderr, "RDMA ERROR: " fmt "\n", ## __VA_ARGS__); \
- if (errp && (*(errp) == NULL)) { \
- error_setg(errp, "RDMA ERROR: " fmt, ## __VA_ARGS__); \
- } \
- } while (0)
-
-#define RDMA_RESOLVE_TIMEOUT_MS 10000
-
-/* Do not merge data if larger than this. */
-#define RDMA_MERGE_MAX (2 * 1024 * 1024)
-#define RDMA_SIGNALED_SEND_MAX (RDMA_MERGE_MAX / 4096)
-
-#define RDMA_REG_CHUNK_SHIFT 20 /* 1 MB */
-
-/*
- * This is only for non-live state being migrated.
- * Instead of RDMA_WRITE messages, we use RDMA_SEND
- * messages for that state, which requires a different
- * delivery design than main memory.
- */
-#define RDMA_SEND_INCREMENT 32768
-
-/*
- * Maximum size infiniband SEND message
- */
-#define RDMA_CONTROL_MAX_BUFFER (512 * 1024)
-#define RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE 4096
-
-#define RDMA_CONTROL_VERSION_CURRENT 1
-/*
- * Capabilities for negotiation.
- */
-#define RDMA_CAPABILITY_PIN_ALL 0x01
-
-/*
- * Add the other flags above to this list of known capabilities
- * as they are introduced.
- */
-static uint32_t known_capabilities = RDMA_CAPABILITY_PIN_ALL;
-
-#define CHECK_ERROR_STATE() \
- do { \
- if (rdma->error_state) { \
- if (!rdma->error_reported) { \
- fprintf(stderr, "RDMA is in an error state waiting migration" \
- " to abort!\n"); \
- rdma->error_reported = 1; \
- } \
- return rdma->error_state; \
- } \
- } while (0);
-
-/*
- * A work request ID is 64-bits and we split up these bits
- * into 3 parts:
- *
- * bits 0-15 : type of control message, 2^16
- * bits 16-29: ram block index, 2^14
- * bits 30-63: ram block chunk number, 2^34
- *
- * The last two bit ranges are only used for RDMA writes,
- * in order to track their completion and potentially
- * also track unregistration status of the message.
- */
-#define RDMA_WRID_TYPE_SHIFT 0UL
-#define RDMA_WRID_BLOCK_SHIFT 16UL
-#define RDMA_WRID_CHUNK_SHIFT 30UL
-
-#define RDMA_WRID_TYPE_MASK \
- ((1UL << RDMA_WRID_BLOCK_SHIFT) - 1UL)
-
-#define RDMA_WRID_BLOCK_MASK \
- (~RDMA_WRID_TYPE_MASK & ((1UL << RDMA_WRID_CHUNK_SHIFT) - 1UL))
-
-#define RDMA_WRID_CHUNK_MASK (~RDMA_WRID_BLOCK_MASK & ~RDMA_WRID_TYPE_MASK)
-
-/*
- * RDMA migration protocol:
- * 1. RDMA Writes (data messages, i.e. RAM)
- * 2. IB Send/Recv (control channel messages)
- */
-enum {
- RDMA_WRID_NONE = 0,
- RDMA_WRID_RDMA_WRITE = 1,
- RDMA_WRID_SEND_CONTROL = 2000,
- RDMA_WRID_RECV_CONTROL = 4000,
-};
-
-const char *wrid_desc[] = {
- [RDMA_WRID_NONE] = "NONE",
- [RDMA_WRID_RDMA_WRITE] = "WRITE RDMA",
- [RDMA_WRID_SEND_CONTROL] = "CONTROL SEND",
- [RDMA_WRID_RECV_CONTROL] = "CONTROL RECV",
-};
-
-/*
- * Work request IDs for IB SEND messages only (not RDMA writes).
- * This is used by the migration protocol to transmit
- * control messages (such as device state and registration commands)
- *
- * We could use more WRs, but we have enough for now.
- */
-enum {
- RDMA_WRID_READY = 0,
- RDMA_WRID_DATA,
- RDMA_WRID_CONTROL,
- RDMA_WRID_MAX,
-};
-
-/*
- * SEND/RECV IB Control Messages.
- */
-enum {
- RDMA_CONTROL_NONE = 0,
- RDMA_CONTROL_ERROR,
- RDMA_CONTROL_READY, /* ready to receive */
- RDMA_CONTROL_QEMU_FILE, /* QEMUFile-transmitted bytes */
- RDMA_CONTROL_RAM_BLOCKS_REQUEST, /* RAMBlock synchronization */
- RDMA_CONTROL_RAM_BLOCKS_RESULT, /* RAMBlock synchronization */
- RDMA_CONTROL_COMPRESS, /* page contains repeat values */
- RDMA_CONTROL_REGISTER_REQUEST, /* dynamic page registration */
- RDMA_CONTROL_REGISTER_RESULT, /* key to use after registration */
- RDMA_CONTROL_REGISTER_FINISHED, /* current iteration finished */
- RDMA_CONTROL_UNREGISTER_REQUEST, /* dynamic UN-registration */
- RDMA_CONTROL_UNREGISTER_FINISHED, /* unpinning finished */
-};
-
-const char *control_desc[] = {
- [RDMA_CONTROL_NONE] = "NONE",
- [RDMA_CONTROL_ERROR] = "ERROR",
- [RDMA_CONTROL_READY] = "READY",
- [RDMA_CONTROL_QEMU_FILE] = "QEMU FILE",
- [RDMA_CONTROL_RAM_BLOCKS_REQUEST] = "RAM BLOCKS REQUEST",
- [RDMA_CONTROL_RAM_BLOCKS_RESULT] = "RAM BLOCKS RESULT",
- [RDMA_CONTROL_COMPRESS] = "COMPRESS",
- [RDMA_CONTROL_REGISTER_REQUEST] = "REGISTER REQUEST",
- [RDMA_CONTROL_REGISTER_RESULT] = "REGISTER RESULT",
- [RDMA_CONTROL_REGISTER_FINISHED] = "REGISTER FINISHED",
- [RDMA_CONTROL_UNREGISTER_REQUEST] = "UNREGISTER REQUEST",
- [RDMA_CONTROL_UNREGISTER_FINISHED] = "UNREGISTER FINISHED",
-};
-
-/*
- * Memory and MR structures used to represent an IB Send/Recv work request.
- * This is *not* used for RDMA writes, only IB Send/Recv.
- */
-typedef struct {
- uint8_t control[RDMA_CONTROL_MAX_BUFFER]; /* actual buffer to register */
- struct ibv_mr *control_mr; /* registration metadata */
- size_t control_len; /* length of the message */
- uint8_t *control_curr; /* start of unconsumed bytes */
-} RDMAWorkRequestData;
-
-/*
- * Negotiate RDMA capabilities during connection-setup time.
- */
-typedef struct {
- uint32_t version;
- uint32_t flags;
-} RDMACapabilities;
-
-static void caps_to_network(RDMACapabilities *cap)
-{
- cap->version = htonl(cap->version);
- cap->flags = htonl(cap->flags);
-}
-
-static void network_to_caps(RDMACapabilities *cap)
-{
- cap->version = ntohl(cap->version);
- cap->flags = ntohl(cap->flags);
-}
-
-/*
- * Representation of a RAMBlock from an RDMA perspective.
- * This is not transmitted, only local.
- * This and subsequent structures cannot be linked lists
- * because we're using a single IB message to transmit
- * the information. It's small anyway, so a list is overkill.
- */
-typedef struct RDMALocalBlock {
- uint8_t *local_host_addr; /* local virtual address */
- uint64_t remote_host_addr; /* remote virtual address */
- uint64_t offset;
- uint64_t length;
- struct ibv_mr **pmr; /* MRs for chunk-level registration */
- struct ibv_mr *mr; /* MR for non-chunk-level registration */
- uint32_t *remote_keys; /* rkeys for chunk-level registration */
- uint32_t remote_rkey; /* rkeys for non-chunk-level registration */
- int index; /* which block are we */
- bool is_ram_block;
- int nb_chunks;
- unsigned long *transit_bitmap;
- unsigned long *unregister_bitmap;
-} RDMALocalBlock;
-
-/*
- * Also represents a RAMblock, but only on the dest.
- * This gets transmitted by the dest during connection-time
- * to the source VM and then is used to populate the
- * corresponding RDMALocalBlock with
- * the information needed to perform the actual RDMA.
- */
-typedef struct QEMU_PACKED RDMARemoteBlock {
- uint64_t remote_host_addr;
- uint64_t offset;
- uint64_t length;
- uint32_t remote_rkey;
- uint32_t padding;
-} RDMARemoteBlock;
-
-static uint64_t htonll(uint64_t v)
-{
- union { uint32_t lv[2]; uint64_t llv; } u;
- u.lv[0] = htonl(v >> 32);
- u.lv[1] = htonl(v & 0xFFFFFFFFULL);
- return u.llv;
-}
-
-static uint64_t ntohll(uint64_t v) {
- union { uint32_t lv[2]; uint64_t llv; } u;
- u.llv = v;
- return ((uint64_t)ntohl(u.lv[0]) << 32) | (uint64_t) ntohl(u.lv[1]);
-}
-
-static void remote_block_to_network(RDMARemoteBlock *rb)
-{
- rb->remote_host_addr = htonll(rb->remote_host_addr);
- rb->offset = htonll(rb->offset);
- rb->length = htonll(rb->length);
- rb->remote_rkey = htonl(rb->remote_rkey);
-}
-
-static void network_to_remote_block(RDMARemoteBlock *rb)
-{
- rb->remote_host_addr = ntohll(rb->remote_host_addr);
- rb->offset = ntohll(rb->offset);
- rb->length = ntohll(rb->length);
- rb->remote_rkey = ntohl(rb->remote_rkey);
-}
-
-/*
- * Virtual address of the above structures used for transmitting
- * the RAMBlock descriptions at connection-time.
- * This structure is *not* transmitted.
- */
-typedef struct RDMALocalBlocks {
- int nb_blocks;
- bool init; /* main memory init complete */
- RDMALocalBlock *block;
-} RDMALocalBlocks;
-
-/*
- * Main data structure for RDMA state.
- * While there is only one copy of this structure being allocated right now,
- * this is the place where one would start if you wanted to consider
- * having more than one RDMA connection open at the same time.
- */
-typedef struct RDMAContext {
- char *host;
- int port;
-
- RDMAWorkRequestData wr_data[RDMA_WRID_MAX];
-
- /*
- * This is used by *_exchange_send() to figure out whether or not
- * the initial "READY" message has already been received or not.
- * This is because other functions may potentially poll() and detect
- * the READY message before send() does, in which case we need to
- * know if it completed.
- */
- int control_ready_expected;
-
- /* number of outstanding writes */
- int nb_sent;
-
- /* store info about current buffer so that we can
- merge it with future sends */
- uint64_t current_addr;
- uint64_t current_length;
- /* index of ram block the current buffer belongs to */
- int current_index;
- /* index of the chunk in the current ram block */
- int current_chunk;
-
- bool pin_all;
-
- /*
- * infiniband-specific variables for opening the device
- * and maintaining connection state and so forth.
- *
- * cm_id also has ibv_context, rdma_event_channel, and ibv_qp in
- * cm_id->verbs, cm_id->channel, and cm_id->qp.
- */
- struct rdma_cm_id *cm_id; /* connection manager ID */
- struct rdma_cm_id *listen_id;
- bool connected;
-
- struct ibv_context *verbs;
- struct rdma_event_channel *channel;
- struct ibv_qp *qp; /* queue pair */
- struct ibv_comp_channel *comp_channel; /* completion channel */
- struct ibv_pd *pd; /* protection domain */
- struct ibv_cq *cq; /* completion queue */
-
- /*
- * If a previous write failed (perhaps because of a failed
- * memory registration, then do not attempt any future work
- * and remember the error state.
- */
- int error_state;
- int error_reported;
-
- /*
- * Description of ram blocks used throughout the code.
- */
- RDMALocalBlocks local_ram_blocks;
- RDMARemoteBlock *block;
-
- /*
- * Migration on *destination* started.
- * Then use coroutine yield function.
- * Source runs in a thread, so we don't care.
- */
- int migration_started_on_destination;
-
- int total_registrations;
- int total_writes;
-
- int unregister_current, unregister_next;
- uint64_t unregistrations[RDMA_SIGNALED_SEND_MAX];
-
- GHashTable *blockmap;
-} RDMAContext;
-
-/*
- * Interface to the rest of the migration call stack.
- */
-typedef struct QEMUFileRDMA {
- RDMAContext *rdma;
- size_t len;
- void *file;
-} QEMUFileRDMA;
-
-/*
- * Main structure for IB Send/Recv control messages.
- * This gets prepended at the beginning of every Send/Recv.
- */
-typedef struct QEMU_PACKED {
- uint32_t len; /* Total length of data portion */
- uint32_t type; /* which control command to perform */
- uint32_t repeat; /* number of commands in data portion of same type */
- uint32_t padding;
-} RDMAControlHeader;
-
-static void control_to_network(RDMAControlHeader *control)
-{
- control->type = htonl(control->type);
- control->len = htonl(control->len);
- control->repeat = htonl(control->repeat);
-}
-
-static void network_to_control(RDMAControlHeader *control)
-{
- control->type = ntohl(control->type);
- control->len = ntohl(control->len);
- control->repeat = ntohl(control->repeat);
-}
-
-/*
- * Register a single Chunk.
- * Information sent by the source VM to inform the dest
- * to register an single chunk of memory before we can perform
- * the actual RDMA operation.
- */
-typedef struct QEMU_PACKED {
- union QEMU_PACKED {
- uint64_t current_addr; /* offset into the ramblock of the chunk */
- uint64_t chunk; /* chunk to lookup if unregistering */
- } key;
- uint32_t current_index; /* which ramblock the chunk belongs to */
- uint32_t padding;
- uint64_t chunks; /* how many sequential chunks to register */
-} RDMARegister;
-
-static void register_to_network(RDMARegister *reg)
-{
- reg->key.current_addr = htonll(reg->key.current_addr);
- reg->current_index = htonl(reg->current_index);
- reg->chunks = htonll(reg->chunks);
-}
-
-static void network_to_register(RDMARegister *reg)
-{
- reg->key.current_addr = ntohll(reg->key.current_addr);
- reg->current_index = ntohl(reg->current_index);
- reg->chunks = ntohll(reg->chunks);
-}
-
-typedef struct QEMU_PACKED {
- uint32_t value; /* if zero, we will madvise() */
- uint32_t block_idx; /* which ram block index */
- uint64_t offset; /* where in the remote ramblock this chunk */
- uint64_t length; /* length of the chunk */
-} RDMACompress;
-
-static void compress_to_network(RDMACompress *comp)
-{
- comp->value = htonl(comp->value);
- comp->block_idx = htonl(comp->block_idx);
- comp->offset = htonll(comp->offset);
- comp->length = htonll(comp->length);
-}
-
-static void network_to_compress(RDMACompress *comp)
-{
- comp->value = ntohl(comp->value);
- comp->block_idx = ntohl(comp->block_idx);
- comp->offset = ntohll(comp->offset);
- comp->length = ntohll(comp->length);
-}
-
-/*
- * The result of the dest's memory registration produces an "rkey"
- * which the source VM must reference in order to perform
- * the RDMA operation.
- */
-typedef struct QEMU_PACKED {
- uint32_t rkey;
- uint32_t padding;
- uint64_t host_addr;
-} RDMARegisterResult;
-
-static void result_to_network(RDMARegisterResult *result)
-{
- result->rkey = htonl(result->rkey);
- result->host_addr = htonll(result->host_addr);
-};
-
-static void network_to_result(RDMARegisterResult *result)
-{
- result->rkey = ntohl(result->rkey);
- result->host_addr = ntohll(result->host_addr);
-};
-
-const char *print_wrid(int wrid);
-static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
- uint8_t *data, RDMAControlHeader *resp,
- int *resp_idx,
- int (*callback)(RDMAContext *rdma));
-
-static inline uint64_t ram_chunk_index(const uint8_t *start,
- const uint8_t *host)
-{
- return ((uintptr_t) host - (uintptr_t) start) >> RDMA_REG_CHUNK_SHIFT;
-}
-
-static inline uint8_t *ram_chunk_start(const RDMALocalBlock *rdma_ram_block,
- uint64_t i)
-{
- return (uint8_t *) (((uintptr_t) rdma_ram_block->local_host_addr)
- + (i << RDMA_REG_CHUNK_SHIFT));
-}
-
-static inline uint8_t *ram_chunk_end(const RDMALocalBlock *rdma_ram_block,
- uint64_t i)
-{
- uint8_t *result = ram_chunk_start(rdma_ram_block, i) +
- (1UL << RDMA_REG_CHUNK_SHIFT);
-
- if (result > (rdma_ram_block->local_host_addr + rdma_ram_block->length)) {
- result = rdma_ram_block->local_host_addr + rdma_ram_block->length;
- }
-
- return result;
-}
-
-static int __qemu_rdma_add_block(RDMAContext *rdma, void *host_addr,
- ram_addr_t block_offset, uint64_t length)
-{
- RDMALocalBlocks *local = &rdma->local_ram_blocks;
- RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
- (void *) block_offset);
- RDMALocalBlock *old = local->block;
-
- assert(block == NULL);
-
- local->block = g_malloc0(sizeof(RDMALocalBlock) * (local->nb_blocks + 1));
-
- if (local->nb_blocks) {
- int x;
-
- for (x = 0; x < local->nb_blocks; x++) {
- g_hash_table_remove(rdma->blockmap, (void *)old[x].offset);
- g_hash_table_insert(rdma->blockmap, (void *)old[x].offset,
- &local->block[x]);
- }
- memcpy(local->block, old, sizeof(RDMALocalBlock) * local->nb_blocks);
- g_free(old);
- }
-
- block = &local->block[local->nb_blocks];
-
- block->local_host_addr = host_addr;
- block->offset = block_offset;
- block->length = length;
- block->index = local->nb_blocks;
- block->nb_chunks = ram_chunk_index(host_addr, host_addr + length) + 1UL;
- block->transit_bitmap = bitmap_new(block->nb_chunks);
- bitmap_clear(block->transit_bitmap, 0, block->nb_chunks);
- block->unregister_bitmap = bitmap_new(block->nb_chunks);
- bitmap_clear(block->unregister_bitmap, 0, block->nb_chunks);
- block->remote_keys = g_malloc0(block->nb_chunks * sizeof(uint32_t));
-
- block->is_ram_block = local->init ? false : true;
-
- g_hash_table_insert(rdma->blockmap, (void *) block_offset, block);
-
- DDPRINTF("Added Block: %d, addr: %" PRIu64 ", offset: %" PRIu64
- " length: %" PRIu64 " end: %" PRIu64 " bits %" PRIu64 " chunks %d\n",
- local->nb_blocks, (uint64_t) block->local_host_addr, block->offset,
- block->length, (uint64_t) (block->local_host_addr + block->length),
- BITS_TO_LONGS(block->nb_chunks) *
- sizeof(unsigned long) * 8, block->nb_chunks);
-
- local->nb_blocks++;
-
- return 0;
-}
-
-/*
- * Memory regions need to be registered with the device and queue pairs setup
- * in advanced before the migration starts. This tells us where the RAM blocks
- * are so that we can register them individually.
- */
-static void qemu_rdma_init_one_block(void *host_addr,
- ram_addr_t block_offset, ram_addr_t length, void *opaque)
-{
- __qemu_rdma_add_block(opaque, host_addr, block_offset, length);
-}
-
-/*
- * Identify the RAMBlocks and their quantity. They will be references to
- * identify chunk boundaries inside each RAMBlock and also be referenced
- * during dynamic page registration.
- */
-static int qemu_rdma_init_ram_blocks(RDMAContext *rdma)
-{
- RDMALocalBlocks *local = &rdma->local_ram_blocks;
-
- assert(rdma->blockmap == NULL);
- rdma->blockmap = g_hash_table_new(g_direct_hash, g_direct_equal);
- memset(local, 0, sizeof *local);
- qemu_ram_foreach_block(qemu_rdma_init_one_block, rdma);
- DPRINTF("Allocated %d local ram block structures\n", local->nb_blocks);
- rdma->block = (RDMARemoteBlock *) g_malloc0(sizeof(RDMARemoteBlock) *
- rdma->local_ram_blocks.nb_blocks);
- local->init = true;
- return 0;
-}
-
-static int __qemu_rdma_delete_block(RDMAContext *rdma, ram_addr_t block_offset)
-{
- RDMALocalBlocks *local = &rdma->local_ram_blocks;
- RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
- (void *) block_offset);
- RDMALocalBlock *old = local->block;
- int x;
-
- assert(block);
-
- if (block->pmr) {
- int j;
-
- for (j = 0; j < block->nb_chunks; j++) {
- if (!block->pmr[j]) {
- continue;
- }
- ibv_dereg_mr(block->pmr[j]);
- rdma->total_registrations--;
- }
- g_free(block->pmr);
- block->pmr = NULL;
- }
-
- if (block->mr) {
- ibv_dereg_mr(block->mr);
- rdma->total_registrations--;
- block->mr = NULL;
- }
-
- g_free(block->transit_bitmap);
- block->transit_bitmap = NULL;
-
- g_free(block->unregister_bitmap);
- block->unregister_bitmap = NULL;
-
- g_free(block->remote_keys);
- block->remote_keys = NULL;
-
- for (x = 0; x < local->nb_blocks; x++) {
- g_hash_table_remove(rdma->blockmap, (void *)old[x].offset);
- }
-
- if (local->nb_blocks > 1) {
-
- local->block = g_malloc0(sizeof(RDMALocalBlock) *
- (local->nb_blocks - 1));
-
- if (block->index) {
- memcpy(local->block, old, sizeof(RDMALocalBlock) * block->index);
- }
-
- if (block->index < (local->nb_blocks - 1)) {
- memcpy(local->block + block->index, old + (block->index + 1),
- sizeof(RDMALocalBlock) *
- (local->nb_blocks - (block->index + 1)));
- }
- } else {
- assert(block == local->block);
- local->block = NULL;
- }
-
- DDPRINTF("Deleted Block: %d, addr: %" PRIu64 ", offset: %" PRIu64
- " length: %" PRIu64 " end: %" PRIu64 " bits %" PRIu64 " chunks %d\n",
- local->nb_blocks, (uint64_t) block->local_host_addr, block->offset,
- block->length, (uint64_t) (block->local_host_addr + block->length),
- BITS_TO_LONGS(block->nb_chunks) *
- sizeof(unsigned long) * 8, block->nb_chunks);
-
- g_free(old);
-
- local->nb_blocks--;
-
- if (local->nb_blocks) {
- for (x = 0; x < local->nb_blocks; x++) {
- g_hash_table_insert(rdma->blockmap, (void *)local->block[x].offset,
- &local->block[x]);
- }
- }
-
- return 0;
-}
-
-/*
- * Put in the log file which RDMA device was opened and the details
- * associated with that device.
- */
-static void qemu_rdma_dump_id(const char *who, struct ibv_context *verbs)
-{
- struct ibv_port_attr port;
-
- if (ibv_query_port(verbs, 1, &port)) {
- fprintf(stderr, "FAILED TO QUERY PORT INFORMATION!\n");
- return;
- }
-
- printf("%s RDMA Device opened: kernel name %s "
- "uverbs device name %s, "
- "infiniband_verbs class device path %s, "
- "infiniband class device path %s, "
- "transport: (%d) %s\n",
- who,
- verbs->device->name,
- verbs->device->dev_name,
- verbs->device->dev_path,
- verbs->device->ibdev_path,
- port.link_layer,
- (port.link_layer == IBV_LINK_LAYER_INFINIBAND) ? "Infiniband" :
- ((port.link_layer == IBV_LINK_LAYER_ETHERNET)
- ? "Ethernet" : "Unknown"));
-}
-
-/*
- * Put in the log file the RDMA gid addressing information,
- * useful for folks who have trouble understanding the
- * RDMA device hierarchy in the kernel.
- */
-static void qemu_rdma_dump_gid(const char *who, struct rdma_cm_id *id)
-{
- char sgid[33];
- char dgid[33];
- inet_ntop(AF_INET6, &id->route.addr.addr.ibaddr.sgid, sgid, sizeof sgid);
- inet_ntop(AF_INET6, &id->route.addr.addr.ibaddr.dgid, dgid, sizeof dgid);
- DPRINTF("%s Source GID: %s, Dest GID: %s\n", who, sgid, dgid);
-}
-
-/*
- * As of now, IPv6 over RoCE / iWARP is not supported by linux.
- * We will try the next addrinfo struct, and fail if there are
- * no other valid addresses to bind against.
- *
- * If user is listening on '[::]', then we will not have a opened a device
- * yet and have no way of verifying if the device is RoCE or not.
- *
- * In this case, the source VM will throw an error for ALL types of
- * connections (both IPv4 and IPv6) if the destination machine does not have
- * a regular infiniband network available for use.
- *
- * The only way to guarantee that an error is thrown for broken kernels is
- * for the management software to choose a *specific* interface at bind time
- * and validate what time of hardware it is.
- *
- * Unfortunately, this puts the user in a fix:
- *
- * If the source VM connects with an IPv4 address without knowing that the
- * destination has bound to '[::]' the migration will unconditionally fail
- * unless the management software is explicitly listening on the the IPv4
- * address while using a RoCE-based device.
- *
- * If the source VM connects with an IPv6 address, then we're OK because we can
- * throw an error on the source (and similarly on the destination).
- *
- * But in mixed environments, this will be broken for a while until it is fixed
- * inside linux.
- *
- * We do provide a *tiny* bit of help in this function: We can list all of the
- * devices in the system and check to see if all the devices are RoCE or
- * Infiniband.
- *
- * If we detect that we have a *pure* RoCE environment, then we can safely
- * thrown an error even if the management software has specified '[::]' as the
- * bind address.
- *
- * However, if there is are multiple hetergeneous devices, then we cannot make
- * this assumption and the user just has to be sure they know what they are
- * doing.
- *
- * Patches are being reviewed on linux-rdma.
- */
-static int qemu_rdma_broken_ipv6_kernel(Error **errp, struct ibv_context *verbs)
-{
- struct ibv_port_attr port_attr;
-
- /* This bug only exists in linux, to our knowledge. */
-#ifdef CONFIG_LINUX
-
- /*
- * Verbs are only NULL if management has bound to '[::]'.
- *
- * Let's iterate through all the devices and see if there any pure IB
- * devices (non-ethernet).
- *
- * If not, then we can safely proceed with the migration.
- * Otherwise, there are no guarantees until the bug is fixed in linux.
- */
- if (!verbs) {
- int num_devices, x;
- struct ibv_device ** dev_list = ibv_get_device_list(&num_devices);
- bool roce_found = false;
- bool ib_found = false;
-
- for (x = 0; x < num_devices; x++) {
- verbs = ibv_open_device(dev_list[x]);
-
- if (ibv_query_port(verbs, 1, &port_attr)) {
- ibv_close_device(verbs);
- ERROR(errp, "Could not query initial IB port");
- return -EINVAL;
- }
-
- if (port_attr.link_layer == IBV_LINK_LAYER_INFINIBAND) {
- ib_found = true;
- } else if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) {
- roce_found = true;
- }
-
- ibv_close_device(verbs);
-
- }
-
- if (roce_found) {
- if (ib_found) {
- fprintf(stderr, "WARN: migrations may fail:"
- " IPv6 over RoCE / iWARP in linux"
- " is broken. But since you appear to have a"
- " mixed RoCE / IB environment, be sure to only"
- " migrate over the IB fabric until the kernel "
- " fixes the bug.\n");
- } else {
- ERROR(errp, "You only have RoCE / iWARP devices in your systems"
- " and your management software has specified '[::]'"
- ", but IPv6 over RoCE / iWARP is not supported in Linux.");
- return -ENONET;
- }
- }
-
- return 0;
- }
-
- /*
- * If we have a verbs context, that means that some other than '[::]' was
- * used by the management software for binding. In which case we can actually
- * warn the user about a potential broken kernel;
- */
-
- /* IB ports start with 1, not 0 */
- if (ibv_query_port(verbs, 1, &port_attr)) {
- ERROR(errp, "Could not query initial IB port");
- return -EINVAL;
- }
-
- if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) {
- ERROR(errp, "Linux kernel's RoCE / iWARP does not support IPv6 "
- "(but patches on linux-rdma in progress)");
- return -ENONET;
- }
-
-#endif
-
- return 0;
-}
-
-/*
- * Figure out which RDMA device corresponds to the requested IP hostname
- * Also create the initial connection manager identifiers for opening
- * the connection.
- */
-static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp)
-{
- int ret;
- struct rdma_addrinfo *res;
- char port_str[16];
- struct rdma_cm_event *cm_event;
- char ip[40] = "unknown";
- struct rdma_addrinfo *e;
-
- if (rdma->host == NULL || !strcmp(rdma->host, "")) {
- ERROR(errp, "RDMA hostname has not been set");
- return -EINVAL;
- }
-
- /* create CM channel */
- rdma->channel = rdma_create_event_channel();
- if (!rdma->channel) {
- ERROR(errp, "could not create CM channel");
- return -EINVAL;
- }
-
- /* create CM id */
- ret = rdma_create_id(rdma->channel, &rdma->cm_id, NULL, RDMA_PS_TCP);
- if (ret) {
- ERROR(errp, "could not create channel id");
- goto err_resolve_create_id;
- }
-
- snprintf(port_str, 16, "%d", rdma->port);
- port_str[15] = '\0';
-
- ret = rdma_getaddrinfo(rdma->host, port_str, NULL, &res);
- if (ret < 0) {
- ERROR(errp, "could not rdma_getaddrinfo address %s", rdma->host);
- goto err_resolve_get_addr;
- }
-
- for (e = res; e != NULL; e = e->ai_next) {
- inet_ntop(e->ai_family,
- &((struct sockaddr_in *) e->ai_dst_addr)->sin_addr, ip, sizeof ip);
- DPRINTF("Trying %s => %s\n", rdma->host, ip);
-
- ret = rdma_resolve_addr(rdma->cm_id, NULL, e->ai_dst_addr,
- RDMA_RESOLVE_TIMEOUT_MS);
- if (!ret) {
- if (e->ai_family == AF_INET6) {
- ret = qemu_rdma_broken_ipv6_kernel(errp, rdma->cm_id->verbs);
- if (ret) {
- continue;
- }
- }
- goto route;
- }
- }
-
- ERROR(errp, "could not resolve address %s", rdma->host);
- goto err_resolve_get_addr;
-
-route:
- qemu_rdma_dump_gid("source_resolve_addr", rdma->cm_id);
-
- ret = rdma_get_cm_event(rdma->channel, &cm_event);
- if (ret) {
- ERROR(errp, "could not perform event_addr_resolved");
- goto err_resolve_get_addr;
- }
-
- if (cm_event->event != RDMA_CM_EVENT_ADDR_RESOLVED) {
- ERROR(errp, "result not equal to event_addr_resolved %s",
- rdma_event_str(cm_event->event));
- perror("rdma_resolve_addr");
- rdma_ack_cm_event(cm_event);
- ret = -EINVAL;
- goto err_resolve_get_addr;
- }
- rdma_ack_cm_event(cm_event);
-
- /* resolve route */
- ret = rdma_resolve_route(rdma->cm_id, RDMA_RESOLVE_TIMEOUT_MS);
- if (ret) {
- ERROR(errp, "could not resolve rdma route");
- goto err_resolve_get_addr;
- }
-
- ret = rdma_get_cm_event(rdma->channel, &cm_event);
- if (ret) {
- ERROR(errp, "could not perform event_route_resolved");
- goto err_resolve_get_addr;
- }
- if (cm_event->event != RDMA_CM_EVENT_ROUTE_RESOLVED) {
- ERROR(errp, "result not equal to event_route_resolved: %s",
- rdma_event_str(cm_event->event));
- rdma_ack_cm_event(cm_event);
- ret = -EINVAL;
- goto err_resolve_get_addr;
- }
- rdma_ack_cm_event(cm_event);
- rdma->verbs = rdma->cm_id->verbs;
- qemu_rdma_dump_id("source_resolve_host", rdma->cm_id->verbs);
- qemu_rdma_dump_gid("source_resolve_host", rdma->cm_id);
- return 0;
-
-err_resolve_get_addr:
- rdma_destroy_id(rdma->cm_id);
- rdma->cm_id = NULL;
-err_resolve_create_id:
- rdma_destroy_event_channel(rdma->channel);
- rdma->channel = NULL;
- return ret;
-}
-
-/*
- * Create protection domain and completion queues
- */
-static int qemu_rdma_alloc_pd_cq(RDMAContext *rdma)
-{
- /* allocate pd */
- rdma->pd = ibv_alloc_pd(rdma->verbs);
- if (!rdma->pd) {
- fprintf(stderr, "failed to allocate protection domain\n");
- return -1;
- }
-
- /* create completion channel */
- rdma->comp_channel = ibv_create_comp_channel(rdma->verbs);
- if (!rdma->comp_channel) {
- fprintf(stderr, "failed to allocate completion channel\n");
- goto err_alloc_pd_cq;
- }
-
- /*
- * Completion queue can be filled by both read and write work requests,
- * so must reflect the sum of both possible queue sizes.
- */
- rdma->cq = ibv_create_cq(rdma->verbs, (RDMA_SIGNALED_SEND_MAX * 3),
- NULL, rdma->comp_channel, 0);
- if (!rdma->cq) {
- fprintf(stderr, "failed to allocate completion queue\n");
- goto err_alloc_pd_cq;
- }
-
- return 0;
-
-err_alloc_pd_cq:
- if (rdma->pd) {
- ibv_dealloc_pd(rdma->pd);
- }
- if (rdma->comp_channel) {
- ibv_destroy_comp_channel(rdma->comp_channel);
- }
- rdma->pd = NULL;
- rdma->comp_channel = NULL;
- return -1;
-
-}
-
-/*
- * Create queue pairs.
- */
-static int qemu_rdma_alloc_qp(RDMAContext *rdma)
-{
- struct ibv_qp_init_attr attr = { 0 };
- int ret;
-
- attr.cap.max_send_wr = RDMA_SIGNALED_SEND_MAX;
- attr.cap.max_recv_wr = 3;
- attr.cap.max_send_sge = 1;
- attr.cap.max_recv_sge = 1;
- attr.send_cq = rdma->cq;
- attr.recv_cq = rdma->cq;
- attr.qp_type = IBV_QPT_RC;
-
- ret = rdma_create_qp(rdma->cm_id, rdma->pd, &attr);
- if (ret) {
- return -1;
- }
-
- rdma->qp = rdma->cm_id->qp;
- return 0;
-}
-
-static int qemu_rdma_reg_whole_ram_blocks(RDMAContext *rdma)
-{
- int i;
- RDMALocalBlocks *local = &rdma->local_ram_blocks;
-
- for (i = 0; i < local->nb_blocks; i++) {
- local->block[i].mr =
- ibv_reg_mr(rdma->pd,
- local->block[i].local_host_addr,
- local->block[i].length,
- IBV_ACCESS_LOCAL_WRITE |
- IBV_ACCESS_REMOTE_WRITE
- );
- if (!local->block[i].mr) {
- perror("Failed to register local dest ram block!\n");
- break;
- }
- rdma->total_registrations++;
- }
-
- if (i >= local->nb_blocks) {
- return 0;
- }
-
- for (i--; i >= 0; i--) {
- ibv_dereg_mr(local->block[i].mr);
- rdma->total_registrations--;
- }
-
- return -1;
-
-}
-
-/*
- * Find the ram block that corresponds to the page requested to be
- * transmitted by QEMU.
- *
- * Once the block is found, also identify which 'chunk' within that
- * block that the page belongs to.
- *
- * This search cannot fail or the migration will fail.
- */
-static int qemu_rdma_search_ram_block(RDMAContext *rdma,
- uint64_t block_offset,
- uint64_t offset,
- uint64_t length,
- uint64_t *block_index,
- uint64_t *chunk_index)
-{
- uint64_t current_addr = block_offset + offset;
- RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
- (void *) block_offset);
- assert(block);
- assert(current_addr >= block->offset);
- assert((current_addr + length) <= (block->offset + block->length));
-
- *block_index = block->index;
- *chunk_index = ram_chunk_index(block->local_host_addr,
- block->local_host_addr + (current_addr - block->offset));
-
- return 0;
-}
-
-/*
- * Register a chunk with IB. If the chunk was already registered
- * previously, then skip.
- *
- * Also return the keys associated with the registration needed
- * to perform the actual RDMA operation.
- */
-static int qemu_rdma_register_and_get_keys(RDMAContext *rdma,
- RDMALocalBlock *block, uint8_t *host_addr,
- uint32_t *lkey, uint32_t *rkey, int chunk,
- uint8_t *chunk_start, uint8_t *chunk_end)
-{
- if (block->mr) {
- if (lkey) {
- *lkey = block->mr->lkey;
- }
- if (rkey) {
- *rkey = block->mr->rkey;
- }
- return 0;
- }
-
- /* allocate memory to store chunk MRs */
- if (!block->pmr) {
- block->pmr = g_malloc0(block->nb_chunks * sizeof(struct ibv_mr *));
- if (!block->pmr) {
- return -1;
- }
- }
-
- /*
- * If 'rkey', then we're the destination, so grant access to the source.
- *
- * If 'lkey', then we're the source VM, so grant access only to ourselves.
- */
- if (!block->pmr[chunk]) {
- uint64_t len = chunk_end - chunk_start;
-
- DDPRINTF("Registering %" PRIu64 " bytes @ %p\n",
- len, chunk_start);
-
- block->pmr[chunk] = ibv_reg_mr(rdma->pd,
- chunk_start, len,
- (rkey ? (IBV_ACCESS_LOCAL_WRITE |
- IBV_ACCESS_REMOTE_WRITE) : 0));
-
- if (!block->pmr[chunk]) {
- perror("Failed to register chunk!");
- fprintf(stderr, "Chunk details: block: %d chunk index %d"
- " start %" PRIu64 " end %" PRIu64 " host %" PRIu64
- " local %" PRIu64 " registrations: %d\n",
- block->index, chunk, (uint64_t) chunk_start,
- (uint64_t) chunk_end, (uint64_t) host_addr,
- (uint64_t) block->local_host_addr,
- rdma->total_registrations);
- return -1;
- }
- rdma->total_registrations++;
- }
-
- if (lkey) {
- *lkey = block->pmr[chunk]->lkey;
- }
- if (rkey) {
- *rkey = block->pmr[chunk]->rkey;
- }
- return 0;
-}
-
-/*
- * Register (at connection time) the memory used for control
- * channel messages.
- */
-static int qemu_rdma_reg_control(RDMAContext *rdma, int idx)
-{
- rdma->wr_data[idx].control_mr = ibv_reg_mr(rdma->pd,
- rdma->wr_data[idx].control, RDMA_CONTROL_MAX_BUFFER,
- IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
- if (rdma->wr_data[idx].control_mr) {
- rdma->total_registrations++;
- return 0;
- }
- fprintf(stderr, "qemu_rdma_reg_control failed!\n");
- return -1;
-}
-
-const char *print_wrid(int wrid)
-{
- if (wrid >= RDMA_WRID_RECV_CONTROL) {
- return wrid_desc[RDMA_WRID_RECV_CONTROL];
- }
- return wrid_desc[wrid];
-}
-
-/*
- * RDMA requires memory registration (mlock/pinning), but this is not good for
- * overcommitment.
- *
- * In preparation for the future where LRU information or workload-specific
- * writable writable working set memory access behavior is available to QEMU
- * it would be nice to have in place the ability to UN-register/UN-pin
- * particular memory regions from the RDMA hardware when it is determine that
- * those regions of memory will likely not be accessed again in the near future.
- *
- * While we do not yet have such information right now, the following
- * compile-time option allows us to perform a non-optimized version of this
- * behavior.
- *
- * By uncommenting this option, you will cause *all* RDMA transfers to be
- * unregistered immediately after the transfer completes on both sides of the
- * connection. This has no effect in 'rdma-pin-all' mode, only regular mode.
- *
- * This will have a terrible impact on migration performance, so until future
- * workload information or LRU information is available, do not attempt to use
- * this feature except for basic testing.
- */
-//#define RDMA_UNREGISTRATION_EXAMPLE
-
-/*
- * Perform a non-optimized memory unregistration after every transfer
- * for demonsration purposes, only if pin-all is not requested.
- *
- * Potential optimizations:
- * 1. Start a new thread to run this function continuously
- - for bit clearing
- - and for receipt of unregister messages
- * 2. Use an LRU.
- * 3. Use workload hints.
- */
-static int qemu_rdma_unregister_waiting(RDMAContext *rdma)
-{
- while (rdma->unregistrations[rdma->unregister_current]) {
- int ret;
- uint64_t wr_id = rdma->unregistrations[rdma->unregister_current];
- uint64_t chunk =
- (wr_id & RDMA_WRID_CHUNK_MASK) >> RDMA_WRID_CHUNK_SHIFT;
- uint64_t index =
- (wr_id & RDMA_WRID_BLOCK_MASK) >> RDMA_WRID_BLOCK_SHIFT;
- RDMALocalBlock *block =
- &(rdma->local_ram_blocks.block[index]);
- RDMARegister reg = { .current_index = index };
- RDMAControlHeader resp = { .type = RDMA_CONTROL_UNREGISTER_FINISHED,
- };
- RDMAControlHeader head = { .len = sizeof(RDMARegister),
- .type = RDMA_CONTROL_UNREGISTER_REQUEST,
- .repeat = 1,
- };
-
- DDPRINTF("Processing unregister for chunk: %" PRIu64
- " at position %d\n", chunk, rdma->unregister_current);
-
- rdma->unregistrations[rdma->unregister_current] = 0;
- rdma->unregister_current++;
-
- if (rdma->unregister_current == RDMA_SIGNALED_SEND_MAX) {
- rdma->unregister_current = 0;
- }
-
-
- /*
- * Unregistration is speculative (because migration is single-threaded
- * and we cannot break the protocol's inifinband message ordering).
- * Thus, if the memory is currently being used for transmission,
- * then abort the attempt to unregister and try again
- * later the next time a completion is received for this memory.
- */
- clear_bit(chunk, block->unregister_bitmap);
-
- if (test_bit(chunk, block->transit_bitmap)) {
- DDPRINTF("Cannot unregister inflight chunk: %" PRIu64 "\n", chunk);
- continue;
- }
-
- DDPRINTF("Sending unregister for chunk: %" PRIu64 "\n", chunk);
-
- ret = ibv_dereg_mr(block->pmr[chunk]);
- block->pmr[chunk] = NULL;
- block->remote_keys[chunk] = 0;
-
- if (ret != 0) {
- perror("unregistration chunk failed");
- return -ret;
- }
- rdma->total_registrations--;
-
- reg.key.chunk = chunk;
- register_to_network(®);
- ret = qemu_rdma_exchange_send(rdma, &head, (uint8_t *) ®,
- &resp, NULL, NULL);
- if (ret < 0) {
- return ret;
- }
-
- DDPRINTF("Unregister for chunk: %" PRIu64 " complete.\n", chunk);
- }
-
- return 0;
-}
-
-static uint64_t qemu_rdma_make_wrid(uint64_t wr_id, uint64_t index,
- uint64_t chunk)
-{
- uint64_t result = wr_id & RDMA_WRID_TYPE_MASK;
-
- result |= (index << RDMA_WRID_BLOCK_SHIFT);
- result |= (chunk << RDMA_WRID_CHUNK_SHIFT);
-
- return result;
-}
-
-/*
- * Set bit for unregistration in the next iteration.
- * We cannot transmit right here, but will unpin later.
- */
-static void qemu_rdma_signal_unregister(RDMAContext *rdma, uint64_t index,
- uint64_t chunk, uint64_t wr_id)
-{
- if (rdma->unregistrations[rdma->unregister_next] != 0) {
- fprintf(stderr, "rdma migration: queue is full!\n");
- } else {
- RDMALocalBlock *block = &(rdma->local_ram_blocks.block[index]);
-
- if (!test_and_set_bit(chunk, block->unregister_bitmap)) {
- DDPRINTF("Appending unregister chunk %" PRIu64
- " at position %d\n", chunk, rdma->unregister_next);
-
- rdma->unregistrations[rdma->unregister_next++] =
- qemu_rdma_make_wrid(wr_id, index, chunk);
-
- if (rdma->unregister_next == RDMA_SIGNALED_SEND_MAX) {
- rdma->unregister_next = 0;
- }
- } else {
- DDPRINTF("Unregister chunk %" PRIu64 " already in queue.\n",
- chunk);
- }
- }
-}
-
-/*
- * Consult the connection manager to see a work request
- * (of any kind) has completed.
- * Return the work request ID that completed.
- */
-static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t *wr_id_out,
- uint32_t *byte_len)
-{
- int ret;
- struct ibv_wc wc;
- uint64_t wr_id;
-
- ret = ibv_poll_cq(rdma->cq, 1, &wc);
-
- if (!ret) {
- *wr_id_out = RDMA_WRID_NONE;
- return 0;
- }
-
- if (ret < 0) {
- fprintf(stderr, "ibv_poll_cq return %d!\n", ret);
- return ret;
- }
-
- wr_id = wc.wr_id & RDMA_WRID_TYPE_MASK;
-
- if (wc.status != IBV_WC_SUCCESS) {
- fprintf(stderr, "ibv_poll_cq wc.status=%d %s!\n",
- wc.status, ibv_wc_status_str(wc.status));
- fprintf(stderr, "ibv_poll_cq wrid=%s!\n", wrid_desc[wr_id]);
-
- return -1;
- }
-
- if (rdma->control_ready_expected &&
- (wr_id >= RDMA_WRID_RECV_CONTROL)) {
- DDDPRINTF("completion %s #%" PRId64 " received (%" PRId64 ")"
- " left %d\n", wrid_desc[RDMA_WRID_RECV_CONTROL],
- wr_id - RDMA_WRID_RECV_CONTROL, wr_id, rdma->nb_sent);
- rdma->control_ready_expected = 0;
- }
-
- if (wr_id == RDMA_WRID_RDMA_WRITE) {
- uint64_t chunk =
- (wc.wr_id & RDMA_WRID_CHUNK_MASK) >> RDMA_WRID_CHUNK_SHIFT;
- uint64_t index =
- (wc.wr_id & RDMA_WRID_BLOCK_MASK) >> RDMA_WRID_BLOCK_SHIFT;
- RDMALocalBlock *block = &(rdma->local_ram_blocks.block[index]);
-
- DDDPRINTF("completions %s (%" PRId64 ") left %d, "
- "block %" PRIu64 ", chunk: %" PRIu64 " %p %p\n",
- print_wrid(wr_id), wr_id, rdma->nb_sent, index, chunk,
- block->local_host_addr, (void *)block->remote_host_addr);
-
- clear_bit(chunk, block->transit_bitmap);
-
- if (rdma->nb_sent > 0) {
- rdma->nb_sent--;
- }
-
- if (!rdma->pin_all) {
- /*
- * FYI: If one wanted to signal a specific chunk to be unregistered
- * using LRU or workload-specific information, this is the function
- * you would call to do so. That chunk would then get asynchronously
- * unregistered later.
- */
-#ifdef RDMA_UNREGISTRATION_EXAMPLE
- qemu_rdma_signal_unregister(rdma, index, chunk, wc.wr_id);
-#endif
- }
- } else {
- DDDPRINTF("other completion %s (%" PRId64 ") received left %d\n",
- print_wrid(wr_id), wr_id, rdma->nb_sent);
- }
-
- *wr_id_out = wc.wr_id;
- if (byte_len) {
- *byte_len = wc.byte_len;
- }
-
- return 0;
-}
-
-/*
- * Block until the next work request has completed.
- *
- * First poll to see if a work request has already completed,
- * otherwise block.
- *
- * If we encounter completed work requests for IDs other than
- * the one we're interested in, then that's generally an error.
- *
- * The only exception is actual RDMA Write completions. These
- * completions only need to be recorded, but do not actually
- * need further processing.
- */
-static int qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
- uint32_t *byte_len)
-{
- int num_cq_events = 0, ret = 0;
- struct ibv_cq *cq;
- void *cq_ctx;
- uint64_t wr_id = RDMA_WRID_NONE, wr_id_in;
-
- if (ibv_req_notify_cq(rdma->cq, 0)) {
- return -1;
- }
- /* poll cq first */
- while (wr_id != wrid_requested) {
- ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
- if (ret < 0) {
- return ret;
- }
-
- wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
-
- if (wr_id == RDMA_WRID_NONE) {
- break;
- }
- if (wr_id != wrid_requested) {
- DDDPRINTF("A Wanted wrid %s (%d) but got %s (%" PRIu64 ")\n",
- print_wrid(wrid_requested),
- wrid_requested, print_wrid(wr_id), wr_id);
- }
- }
-
- if (wr_id == wrid_requested) {
- return 0;
- }
-
- while (1) {
- /*
- * Coroutine doesn't start until process_incoming_migration()
- * so don't yield unless we know we're running inside of a coroutine.
- */
- if (rdma->migration_started_on_destination) {
- yield_until_fd_readable(rdma->comp_channel->fd);
- }
-
- if (ibv_get_cq_event(rdma->comp_channel, &cq, &cq_ctx)) {
- perror("ibv_get_cq_event");
- goto err_block_for_wrid;
- }
-
- num_cq_events++;
-
- if (ibv_req_notify_cq(cq, 0)) {
- goto err_block_for_wrid;
- }
-
- while (wr_id != wrid_requested) {
- ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
- if (ret < 0) {
- goto err_block_for_wrid;
- }
-
- wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
-
- if (wr_id == RDMA_WRID_NONE) {
- break;
- }
- if (wr_id != wrid_requested) {
- DDDPRINTF("B Wanted wrid %s (%d) but got %s (%" PRIu64 ")\n",
- print_wrid(wrid_requested), wrid_requested,
- print_wrid(wr_id), wr_id);
- }
- }
-
- if (wr_id == wrid_requested) {
- goto success_block_for_wrid;
- }
- }
-
-success_block_for_wrid:
- if (num_cq_events) {
- ibv_ack_cq_events(cq, num_cq_events);
- }
- return 0;
-
-err_block_for_wrid:
- if (num_cq_events) {
- ibv_ack_cq_events(cq, num_cq_events);
- }
- return ret;
-}
-
-/*
- * Post a SEND message work request for the control channel
- * containing some data and block until the post completes.
- */
-static int qemu_rdma_post_send_control(RDMAContext *rdma, uint8_t *buf,
- RDMAControlHeader *head)
-{
- int ret = 0;
- RDMAWorkRequestData *wr = &rdma->wr_data[RDMA_WRID_CONTROL];
- struct ibv_send_wr *bad_wr;
- struct ibv_sge sge = {
- .addr = (uint64_t)(wr->control),
- .length = head->len + sizeof(RDMAControlHeader),
- .lkey = wr->control_mr->lkey,
- };
- struct ibv_send_wr send_wr = {
- .wr_id = RDMA_WRID_SEND_CONTROL,
- .opcode = IBV_WR_SEND,
- .send_flags = IBV_SEND_SIGNALED,
- .sg_list = &sge,
- .num_sge = 1,
- };
-
- DDDPRINTF("CONTROL: sending %s..\n", control_desc[head->type]);
-
- /*
- * We don't actually need to do a memcpy() in here if we used
- * the "sge" properly, but since we're only sending control messages
- * (not RAM in a performance-critical path), then its OK for now.
- *
- * The copy makes the RDMAControlHeader simpler to manipulate
- * for the time being.
- */
- assert(head->len <= RDMA_CONTROL_MAX_BUFFER - sizeof(*head));
- memcpy(wr->control, head, sizeof(RDMAControlHeader));
- control_to_network((void *) wr->control);
-
- if (buf) {
- memcpy(wr->control + sizeof(RDMAControlHeader), buf, head->len);
- }
-
-
- ret = ibv_post_send(rdma->qp, &send_wr, &bad_wr);
-
- if (ret > 0) {
- fprintf(stderr, "Failed to use post IB SEND for control!\n");
- return -ret;
- }
-
- ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_SEND_CONTROL, NULL);
- if (ret < 0) {
- fprintf(stderr, "rdma migration: send polling control error!\n");
- }
-
- return ret;
-}
-
-/*
- * Post a RECV work request in anticipation of some future receipt
- * of data on the control channel.
- */
-static int qemu_rdma_post_recv_control(RDMAContext *rdma, int idx)
-{
- struct ibv_recv_wr *bad_wr;
- struct ibv_sge sge = {
- .addr = (uint64_t)(rdma->wr_data[idx].control),
- .length = RDMA_CONTROL_MAX_BUFFER,
- .lkey = rdma->wr_data[idx].control_mr->lkey,
- };
-
- struct ibv_recv_wr recv_wr = {
- .wr_id = RDMA_WRID_RECV_CONTROL + idx,
- .sg_list = &sge,
- .num_sge = 1,
- };
-
-
- if (ibv_post_recv(rdma->qp, &recv_wr, &bad_wr)) {
- return -1;
- }
-
- return 0;
-}
-
-/*
- * Block and wait for a RECV control channel message to arrive.
- */
-static int qemu_rdma_exchange_get_response(RDMAContext *rdma,
- RDMAControlHeader *head, int expecting, int idx)
-{
- uint32_t byte_len;
- int ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RECV_CONTROL + idx,
- &byte_len);
-
- if (ret < 0) {
- fprintf(stderr, "rdma migration: recv polling control error!\n");
- return ret;
- }
-
- network_to_control((void *) rdma->wr_data[idx].control);
- memcpy(head, rdma->wr_data[idx].control, sizeof(RDMAControlHeader));
-
- DDDPRINTF("CONTROL: %s receiving...\n", control_desc[expecting]);
-
- if (expecting == RDMA_CONTROL_NONE) {
- DDDPRINTF("Surprise: got %s (%d)\n",
- control_desc[head->type], head->type);
- } else if (head->type != expecting || head->type == RDMA_CONTROL_ERROR) {
- fprintf(stderr, "Was expecting a %s (%d) control message"
- ", but got: %s (%d), length: %d\n",
- control_desc[expecting], expecting,
- control_desc[head->type], head->type, head->len);
- return -EIO;
- }
- if (head->len > RDMA_CONTROL_MAX_BUFFER - sizeof(*head)) {
- fprintf(stderr, "too long length: %d\n", head->len);
- return -EINVAL;
- }
- if (sizeof(*head) + head->len != byte_len) {
- fprintf(stderr, "Malformed length: %d byte_len %d\n",
- head->len, byte_len);
- return -EINVAL;
- }
-
- return 0;
-}
-
-/*
- * When a RECV work request has completed, the work request's
- * buffer is pointed at the header.
- *
- * This will advance the pointer to the data portion
- * of the control message of the work request's buffer that
- * was populated after the work request finished.
- */
-static void qemu_rdma_move_header(RDMAContext *rdma, int idx,
- RDMAControlHeader *head)
-{
- rdma->wr_data[idx].control_len = head->len;
- rdma->wr_data[idx].control_curr =
- rdma->wr_data[idx].control + sizeof(RDMAControlHeader);
-}
-
-/*
- * This is an 'atomic' high-level operation to deliver a single, unified
- * control-channel message.
- *
- * Additionally, if the user is expecting some kind of reply to this message,
- * they can request a 'resp' response message be filled in by posting an
- * additional work request on behalf of the user and waiting for an additional
- * completion.
- *
- * The extra (optional) response is used during registration to us from having
- * to perform an *additional* exchange of message just to provide a response by
- * instead piggy-backing on the acknowledgement.
- */
-static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
- uint8_t *data, RDMAControlHeader *resp,
- int *resp_idx,
- int (*callback)(RDMAContext *rdma))
-{
- int ret = 0;
-
- /*
- * Wait until the dest is ready before attempting to deliver the message
- * by waiting for a READY message.
- */
- if (rdma->control_ready_expected) {
- RDMAControlHeader resp;
- ret = qemu_rdma_exchange_get_response(rdma,
- &resp, RDMA_CONTROL_READY, RDMA_WRID_READY);
- if (ret < 0) {
- return ret;
- }
- }
-
- /*
- * If the user is expecting a response, post a WR in anticipation of it.
- */
- if (resp) {
- ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_DATA);
- if (ret) {
- fprintf(stderr, "rdma migration: error posting"
- " extra control recv for anticipated result!");
- return ret;
- }
- }
-
- /*
- * Post a WR to replace the one we just consumed for the READY message.
- */
- ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
- if (ret) {
- fprintf(stderr, "rdma migration: error posting first control recv!");
- return ret;
- }
-
- /*
- * Deliver the control message that was requested.
- */
- ret = qemu_rdma_post_send_control(rdma, data, head);
-
- if (ret < 0) {
- fprintf(stderr, "Failed to send control buffer!\n");
- return ret;
- }
-
- /*
- * If we're expecting a response, block and wait for it.
- */
- if (resp) {
- if (callback) {
- DDPRINTF("Issuing callback before receiving response...\n");
- ret = callback(rdma);
- if (ret < 0) {
- return ret;
- }
- }
-
- DDPRINTF("Waiting for response %s\n", control_desc[resp->type]);
- ret = qemu_rdma_exchange_get_response(rdma, resp,
- resp->type, RDMA_WRID_DATA);
-
- if (ret < 0) {
- return ret;
- }
-
- qemu_rdma_move_header(rdma, RDMA_WRID_DATA, resp);
- if (resp_idx) {
- *resp_idx = RDMA_WRID_DATA;
- }
- DDPRINTF("Response %s received.\n", control_desc[resp->type]);
- }
-
- rdma->control_ready_expected = 1;
-
- return 0;
-}
-
-/*
- * This is an 'atomic' high-level operation to receive a single, unified
- * control-channel message.
- */
-static int qemu_rdma_exchange_recv(RDMAContext *rdma, RDMAControlHeader *head,
- int expecting)
-{
- RDMAControlHeader ready = {
- .len = 0,
- .type = RDMA_CONTROL_READY,
- .repeat = 1,
- };
- int ret;
-
- /*
- * Inform the source that we're ready to receive a message.
- */
- ret = qemu_rdma_post_send_control(rdma, NULL, &ready);
-
- if (ret < 0) {
- fprintf(stderr, "Failed to send control buffer!\n");
- return ret;
- }
-
- /*
- * Block and wait for the message.
- */
- ret = qemu_rdma_exchange_get_response(rdma, head,
- expecting, RDMA_WRID_READY);
-
- if (ret < 0) {
- return ret;
- }
-
- qemu_rdma_move_header(rdma, RDMA_WRID_READY, head);
-
- /*
- * Post a new RECV work request to replace the one we just consumed.
- */
- ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
- if (ret) {
- fprintf(stderr, "rdma migration: error posting second control recv!");
- return ret;
- }
-
- return 0;
-}
-
-/*
- * Write an actual chunk of memory using RDMA.
- *
- * If we're using dynamic registration on the dest-side, we have to
- * send a registration command first.
- */
-static int qemu_rdma_write_one(QEMUFile *f, RDMAContext *rdma,
- int current_index, uint64_t current_addr,
- uint64_t length)
-{
- struct ibv_sge sge;
- struct ibv_send_wr send_wr = { 0 };
- struct ibv_send_wr *bad_wr;
- int reg_result_idx, ret, count = 0;
- uint64_t chunk, chunks;
- uint8_t *chunk_start, *chunk_end;
- RDMALocalBlock *block = &(rdma->local_ram_blocks.block[current_index]);
- RDMARegister reg;
- RDMARegisterResult *reg_result;
- RDMAControlHeader resp = { .type = RDMA_CONTROL_REGISTER_RESULT };
- RDMAControlHeader head = { .len = sizeof(RDMARegister),
- .type = RDMA_CONTROL_REGISTER_REQUEST,
- .repeat = 1,
- };
-
-retry:
- sge.addr = (uint64_t)(block->local_host_addr +
- (current_addr - block->offset));
- sge.length = length;
-
- chunk = ram_chunk_index(block->local_host_addr, (uint8_t *) sge.addr);
- chunk_start = ram_chunk_start(block, chunk);
-
- if (block->is_ram_block) {
- chunks = length / (1UL << RDMA_REG_CHUNK_SHIFT);
-
- if (chunks && ((length % (1UL << RDMA_REG_CHUNK_SHIFT)) == 0)) {
- chunks--;
- }
- } else {
- chunks = block->length / (1UL << RDMA_REG_CHUNK_SHIFT);
-
- if (chunks && ((block->length % (1UL << RDMA_REG_CHUNK_SHIFT)) == 0)) {
- chunks--;
- }
- }
-
- DDPRINTF("Writing %" PRIu64 " chunks, (%" PRIu64 " MB)\n",
- chunks + 1, (chunks + 1) * (1UL << RDMA_REG_CHUNK_SHIFT) / 1024 / 1024);
-
- chunk_end = ram_chunk_end(block, chunk + chunks);
-
- if (!rdma->pin_all) {
-#ifdef RDMA_UNREGISTRATION_EXAMPLE
- qemu_rdma_unregister_waiting(rdma);
-#endif
- }
-
- while (test_bit(chunk, block->transit_bitmap)) {
- (void)count;
- DDPRINTF("(%d) Not clobbering: block: %d chunk %" PRIu64
- " current %" PRIu64 " len %" PRIu64 " %d %d\n",
- count++, current_index, chunk,
- sge.addr, length, rdma->nb_sent, block->nb_chunks);
-
- ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
-
- if (ret < 0) {
- fprintf(stderr, "Failed to Wait for previous write to complete "
- "block %d chunk %" PRIu64
- " current %" PRIu64 " len %" PRIu64 " %d\n",
- current_index, chunk, sge.addr, length, rdma->nb_sent);
- return ret;
- }
- }
-
- if (!rdma->pin_all || !block->is_ram_block) {
- if (!block->remote_keys[chunk]) {
- /*
- * This chunk has not yet been registered, so first check to see
- * if the entire chunk is zero. If so, tell the other size to
- * memset() + madvise() the entire chunk without RDMA.
- */
-
- if (can_use_buffer_find_nonzero_offset((void *)sge.addr, length)
- && buffer_find_nonzero_offset((void *)sge.addr,
- length) == length) {
- RDMACompress comp = {
- .offset = current_addr,
- .value = 0,
- .block_idx = current_index,
- .length = length,
- };
-
- head.len = sizeof(comp);
- head.type = RDMA_CONTROL_COMPRESS;
-
- DDPRINTF("Entire chunk is zero, sending compress: %"
- PRIu64 " for %d "
- "bytes, index: %d, offset: %" PRId64 "...\n",
- chunk, sge.length, current_index, current_addr);
-
- compress_to_network(&comp);
- ret = qemu_rdma_exchange_send(rdma, &head,
- (uint8_t *) &comp, NULL, NULL, NULL);
-
- if (ret < 0) {
- return -EIO;
- }
-
- acct_update_position(f, sge.length, true);
-
- return 1;
- }
-
- /*
- * Otherwise, tell other side to register.
- */
- reg.current_index = current_index;
- if (block->is_ram_block) {
- reg.key.current_addr = current_addr;
- } else {
- reg.key.chunk = chunk;
- }
- reg.chunks = chunks;
-
- DDPRINTF("Sending registration request chunk %" PRIu64 " for %d "
- "bytes, index: %d, offset: %" PRId64 "...\n",
- chunk, sge.length, current_index, current_addr);
-
- register_to_network(®);
- ret = qemu_rdma_exchange_send(rdma, &head, (uint8_t *) ®,
- &resp, ®_result_idx, NULL);
- if (ret < 0) {
- return ret;
- }
-
- /* try to overlap this single registration with the one we sent. */
- if (qemu_rdma_register_and_get_keys(rdma, block,
- (uint8_t *) sge.addr,
- &sge.lkey, NULL, chunk,
- chunk_start, chunk_end)) {
- fprintf(stderr, "cannot get lkey!\n");
- return -EINVAL;
- }
-
- reg_result = (RDMARegisterResult *)
- rdma->wr_data[reg_result_idx].control_curr;
-
- network_to_result(reg_result);
-
- DDPRINTF("Received registration result:"
- " my key: %x their key %x, chunk %" PRIu64 "\n",
- block->remote_keys[chunk], reg_result->rkey, chunk);
-
- block->remote_keys[chunk] = reg_result->rkey;
- block->remote_host_addr = reg_result->host_addr;
- } else {
- /* already registered before */
- if (qemu_rdma_register_and_get_keys(rdma, block,
- (uint8_t *)sge.addr,
- &sge.lkey, NULL, chunk,
- chunk_start, chunk_end)) {
- fprintf(stderr, "cannot get lkey!\n");
- return -EINVAL;
- }
- }
-
- send_wr.wr.rdma.rkey = block->remote_keys[chunk];
- } else {
- send_wr.wr.rdma.rkey = block->remote_rkey;
-
- if (qemu_rdma_register_and_get_keys(rdma, block, (uint8_t *)sge.addr,
- &sge.lkey, NULL, chunk,
- chunk_start, chunk_end)) {
- fprintf(stderr, "cannot get lkey!\n");
- return -EINVAL;
- }
- }
-
- /*
- * Encode the ram block index and chunk within this wrid.
- * We will use this information at the time of completion
- * to figure out which bitmap to check against and then which
- * chunk in the bitmap to look for.
- */
- send_wr.wr_id = qemu_rdma_make_wrid(RDMA_WRID_RDMA_WRITE,
- current_index, chunk);
-
- send_wr.opcode = IBV_WR_RDMA_WRITE;
- send_wr.send_flags = IBV_SEND_SIGNALED;
- send_wr.sg_list = &sge;
- send_wr.num_sge = 1;
- send_wr.wr.rdma.remote_addr = block->remote_host_addr +
- (current_addr - block->offset);
-
- DDDPRINTF("Posting chunk: %" PRIu64 ", addr: %lx"
- " remote: %lx, bytes %" PRIu32 "\n",
- chunk, sge.addr, send_wr.wr.rdma.remote_addr,
- sge.length);
-
- /*
- * ibv_post_send() does not return negative error numbers,
- * per the specification they are positive - no idea why.
- */
- ret = ibv_post_send(rdma->qp, &send_wr, &bad_wr);
-
- if (ret == ENOMEM) {
- DDPRINTF("send queue is full. wait a little....\n");
- ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
- if (ret < 0) {
- fprintf(stderr, "rdma migration: failed to make "
- "room in full send queue! %d\n", ret);
- return ret;
- }
-
- goto retry;
-
- } else if (ret > 0) {
- perror("rdma migration: post rdma write failed");
- return -ret;
- }
-
- set_bit(chunk, block->transit_bitmap);
- acct_update_position(f, sge.length, false);
- rdma->total_writes++;
-
- return 0;
-}
-
-/*
- * Push out any unwritten RDMA operations.
- *
- * We support sending out multiple chunks at the same time.
- * Not all of them need to get signaled in the completion queue.
- */
-static int qemu_rdma_write_flush(QEMUFile *f, RDMAContext *rdma)
-{
- int ret;
-
- if (!rdma->current_length) {
- return 0;
- }
-
- ret = qemu_rdma_write_one(f, rdma,
- rdma->current_index, rdma->current_addr, rdma->current_length);
-
- if (ret < 0) {
- return ret;
- }
-
- if (ret == 0) {
- rdma->nb_sent++;
- DDDPRINTF("sent total: %d\n", rdma->nb_sent);
- }
-
- rdma->current_length = 0;
- rdma->current_addr = 0;
-
- return 0;
-}
-
-static inline int qemu_rdma_buffer_mergable(RDMAContext *rdma,
- uint64_t offset, uint64_t len)
-{
- RDMALocalBlock *block;
- uint8_t *host_addr;
- uint8_t *chunk_end;
-
- if (rdma->current_index < 0) {
- return 0;
- }
-
- if (rdma->current_chunk < 0) {
- return 0;
- }
-
- block = &(rdma->local_ram_blocks.block[rdma->current_index]);
- host_addr = block->local_host_addr + (offset - block->offset);
- chunk_end = ram_chunk_end(block, rdma->current_chunk);
-
- if (rdma->current_length == 0) {
- return 0;
- }
-
- /*
- * Only merge into chunk sequentially.
- */
- if (offset != (rdma->current_addr + rdma->current_length)) {
- return 0;
- }
-
- if (offset < block->offset) {
- return 0;
- }
-
- if ((offset + len) > (block->offset + block->length)) {
- return 0;
- }
-
- if ((host_addr + len) > chunk_end) {
- return 0;
- }
-
- return 1;
-}
-
-/*
- * We're not actually writing here, but doing three things:
- *
- * 1. Identify the chunk the buffer belongs to.
- * 2. If the chunk is full or the buffer doesn't belong to the current
- * chunk, then start a new chunk and flush() the old chunk.
- * 3. To keep the hardware busy, we also group chunks into batches
- * and only require that a batch gets acknowledged in the completion
- * qeueue instead of each individual chunk.
- */
-static int qemu_rdma_write(QEMUFile *f, RDMAContext *rdma,
- uint64_t block_offset, uint64_t offset,
- uint64_t len)
-{
- uint64_t current_addr = block_offset + offset;
- uint64_t index = rdma->current_index;
- uint64_t chunk = rdma->current_chunk;
- int ret;
-
- /* If we cannot merge it, we flush the current buffer first. */
- if (!qemu_rdma_buffer_mergable(rdma, current_addr, len)) {
- ret = qemu_rdma_write_flush(f, rdma);
- if (ret) {
- return ret;
- }
- rdma->current_length = 0;
- rdma->current_addr = current_addr;
-
- ret = qemu_rdma_search_ram_block(rdma, block_offset,
- offset, len, &index, &chunk);
- if (ret) {
- fprintf(stderr, "ram block search failed\n");
- return ret;
- }
- rdma->current_index = index;
- rdma->current_chunk = chunk;
- }
-
- /* merge it */
- rdma->current_length += len;
-
- /* flush it if buffer is too large */
- if (rdma->current_length >= RDMA_MERGE_MAX) {
- return qemu_rdma_write_flush(f, rdma);
- }
-
- return 0;
-}
-
-static void qemu_rdma_cleanup(RDMAContext *rdma)
-{
- struct rdma_cm_event *cm_event;
- int ret, idx;
-
- if (rdma->cm_id && rdma->connected) {
- if (rdma->error_state) {
- RDMAControlHeader head = { .len = 0,
- .type = RDMA_CONTROL_ERROR,
- .repeat = 1,
- };
- fprintf(stderr, "Early error. Sending error.\n");
- qemu_rdma_post_send_control(rdma, NULL, &head);
- }
-
- ret = rdma_disconnect(rdma->cm_id);
- if (!ret) {
- DDPRINTF("waiting for disconnect\n");
- ret = rdma_get_cm_event(rdma->channel, &cm_event);
- if (!ret) {
- rdma_ack_cm_event(cm_event);
- }
- }
- DDPRINTF("Disconnected.\n");
- rdma->connected = false;
- }
-
- g_free(rdma->block);
- rdma->block = NULL;
-
- for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
- if (rdma->wr_data[idx].control_mr) {
- rdma->total_registrations--;
- ibv_dereg_mr(rdma->wr_data[idx].control_mr);
- }
- rdma->wr_data[idx].control_mr = NULL;
- }
-
- if (rdma->local_ram_blocks.block) {
- while (rdma->local_ram_blocks.nb_blocks) {
- __qemu_rdma_delete_block(rdma,
- rdma->local_ram_blocks.block->offset);
- }
- }
-
- if (rdma->cq) {
- ibv_destroy_cq(rdma->cq);
- rdma->cq = NULL;
- }
- if (rdma->comp_channel) {
- ibv_destroy_comp_channel(rdma->comp_channel);
- rdma->comp_channel = NULL;
- }
- if (rdma->pd) {
- ibv_dealloc_pd(rdma->pd);
- rdma->pd = NULL;
- }
- if (rdma->listen_id) {
- rdma_destroy_id(rdma->listen_id);
- rdma->listen_id = NULL;
- }
- if (rdma->cm_id) {
- if (rdma->qp) {
- rdma_destroy_qp(rdma->cm_id);
- rdma->qp = NULL;
- }
- rdma_destroy_id(rdma->cm_id);
- rdma->cm_id = NULL;
- }
- if (rdma->channel) {
- rdma_destroy_event_channel(rdma->channel);
- rdma->channel = NULL;
- }
- g_free(rdma->host);
- rdma->host = NULL;
-}
-
-
-static int qemu_rdma_source_init(RDMAContext *rdma, Error **errp, bool pin_all)
-{
- int ret, idx;
- Error *local_err = NULL, **temp = &local_err;
-
- /*
- * Will be validated against destination's actual capabilities
- * after the connect() completes.
- */
- rdma->pin_all = pin_all;
-
- ret = qemu_rdma_resolve_host(rdma, temp);
- if (ret) {
- goto err_rdma_source_init;
- }
-
- ret = qemu_rdma_alloc_pd_cq(rdma);
- if (ret) {
- ERROR(temp, "rdma migration: error allocating pd and cq! Your mlock()"
- " limits may be too low. Please check $ ulimit -a # and "
- "search for 'ulimit -l' in the output");
- goto err_rdma_source_init;
- }
-
- ret = qemu_rdma_alloc_qp(rdma);
- if (ret) {
- ERROR(temp, "rdma migration: error allocating qp!");
- goto err_rdma_source_init;
- }
-
- ret = qemu_rdma_init_ram_blocks(rdma);
- if (ret) {
- ERROR(temp, "rdma migration: error initializing ram blocks!");
- goto err_rdma_source_init;
- }
-
- for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
- ret = qemu_rdma_reg_control(rdma, idx);
- if (ret) {
- ERROR(temp, "rdma migration: error registering %d control!",
- idx);
- goto err_rdma_source_init;
- }
- }
-
- return 0;
-
-err_rdma_source_init:
- error_propagate(errp, local_err);
- qemu_rdma_cleanup(rdma);
- return -1;
-}
-
-static int qemu_rdma_connect(RDMAContext *rdma, Error **errp)
-{
- RDMACapabilities cap = {
- .version = RDMA_CONTROL_VERSION_CURRENT,
- .flags = 0,
- };
- struct rdma_conn_param conn_param = { .initiator_depth = 2,
- .retry_count = 5,
- .private_data = &cap,
- .private_data_len = sizeof(cap),
- };
- struct rdma_cm_event *cm_event;
- int ret;
-
- /*
- * Only negotiate the capability with destination if the user
- * on the source first requested the capability.
- */
- if (rdma->pin_all) {
- DPRINTF("Server pin-all memory requested.\n");
- cap.flags |= RDMA_CAPABILITY_PIN_ALL;
- }
-
- caps_to_network(&cap);
-
- ret = rdma_connect(rdma->cm_id, &conn_param);
- if (ret) {
- perror("rdma_connect");
- ERROR(errp, "connecting to destination!");
- rdma_destroy_id(rdma->cm_id);
- rdma->cm_id = NULL;
- goto err_rdma_source_connect;
- }
-
- ret = rdma_get_cm_event(rdma->channel, &cm_event);
- if (ret) {
- perror("rdma_get_cm_event after rdma_connect");
- ERROR(errp, "connecting to destination!");
- rdma_ack_cm_event(cm_event);
- rdma_destroy_id(rdma->cm_id);
- rdma->cm_id = NULL;
- goto err_rdma_source_connect;
- }
-
- if (cm_event->event != RDMA_CM_EVENT_ESTABLISHED) {
- perror("rdma_get_cm_event != EVENT_ESTABLISHED after rdma_connect");
- ERROR(errp, "connecting to destination!");
- rdma_ack_cm_event(cm_event);
- rdma_destroy_id(rdma->cm_id);
- rdma->cm_id = NULL;
- goto err_rdma_source_connect;
- }
- rdma->connected = true;
-
- memcpy(&cap, cm_event->param.conn.private_data, sizeof(cap));
- network_to_caps(&cap);
-
- /*
- * Verify that the *requested* capabilities are supported by the destination
- * and disable them otherwise.
- */
- if (rdma->pin_all && !(cap.flags & RDMA_CAPABILITY_PIN_ALL)) {
- ERROR(errp, "Server cannot support pinning all memory. "
- "Will register memory dynamically.");
- rdma->pin_all = false;
- }
-
- DPRINTF("Pin all memory: %s\n", rdma->pin_all ? "enabled" : "disabled");
-
- rdma_ack_cm_event(cm_event);
-
- ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
- if (ret) {
- ERROR(errp, "posting second control recv!");
- goto err_rdma_source_connect;
- }
-
- rdma->control_ready_expected = 1;
- rdma->nb_sent = 0;
- return 0;
-
-err_rdma_source_connect:
- qemu_rdma_cleanup(rdma);
- return -1;
-}
-
-static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp)
-{
- int ret = -EINVAL, idx;
- struct rdma_cm_id *listen_id;
- char ip[40] = "unknown";
- struct rdma_addrinfo *res;
- char port_str[16];
-
- for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
- rdma->wr_data[idx].control_len = 0;
- rdma->wr_data[idx].control_curr = NULL;
- }
-
- if (rdma->host == NULL) {
- ERROR(errp, "RDMA host is not set!");
- rdma->error_state = -EINVAL;
- return -1;
- }
- /* create CM channel */
- rdma->channel = rdma_create_event_channel();
- if (!rdma->channel) {
- ERROR(errp, "could not create rdma event channel");
- rdma->error_state = -EINVAL;
- return -1;
- }
-
- /* create CM id */
- ret = rdma_create_id(rdma->channel, &listen_id, NULL, RDMA_PS_TCP);
- if (ret) {
- ERROR(errp, "could not create cm_id!");
- goto err_dest_init_create_listen_id;
- }
-
- snprintf(port_str, 16, "%d", rdma->port);
- port_str[15] = '\0';
-
- if (rdma->host && strcmp("", rdma->host)) {
- struct rdma_addrinfo *e;
-
- ret = rdma_getaddrinfo(rdma->host, port_str, NULL, &res);
- if (ret < 0) {
- ERROR(errp, "could not rdma_getaddrinfo address %s", rdma->host);
- goto err_dest_init_bind_addr;
- }
-
- for (e = res; e != NULL; e = e->ai_next) {
- inet_ntop(e->ai_family,
- &((struct sockaddr_in *) e->ai_dst_addr)->sin_addr, ip, sizeof ip);
- DPRINTF("Trying %s => %s\n", rdma->host, ip);
- ret = rdma_bind_addr(listen_id, e->ai_dst_addr);
- if (!ret) {
- if (e->ai_family == AF_INET6) {
- ret = qemu_rdma_broken_ipv6_kernel(errp, listen_id->verbs);
- if (ret) {
- continue;
- }
- }
-
- goto listen;
- }
- }
-
- ERROR(errp, "Error: could not rdma_bind_addr!");
- goto err_dest_init_bind_addr;
- } else {
- ERROR(errp, "migration host and port not specified!");
- ret = -EINVAL;
- goto err_dest_init_bind_addr;
- }
-listen:
-
- rdma->listen_id = listen_id;
- qemu_rdma_dump_gid("dest_init", listen_id);
- return 0;
-
-err_dest_init_bind_addr:
- rdma_destroy_id(listen_id);
-err_dest_init_create_listen_id:
- rdma_destroy_event_channel(rdma->channel);
- rdma->channel = NULL;
- rdma->error_state = ret;
- return ret;
-
-}
-
-static void *qemu_rdma_data_init(const char *host_port, Error **errp)
-{
- RDMAContext *rdma = NULL;
- InetSocketAddress *addr;
-
- if (host_port) {
- rdma = g_malloc0(sizeof(RDMAContext));
- memset(rdma, 0, sizeof(RDMAContext));
- rdma->current_index = -1;
- rdma->current_chunk = -1;
-
- addr = inet_parse(host_port, NULL);
- if (addr != NULL) {
- rdma->port = atoi(addr->port);
- rdma->host = g_strdup(addr->host);
- } else {
- ERROR(errp, "bad RDMA migration address '%s'", host_port);
- g_free(rdma);
- rdma = NULL;
- }
-
- qapi_free_InetSocketAddress(addr);
- }
-
- return rdma;
-}
-
-/*
- * QEMUFile interface to the control channel.
- * SEND messages for control only.
- * VM's ram is handled with regular RDMA messages.
- */
-static int qemu_rdma_put_buffer(void *opaque, const uint8_t *buf,
- int64_t pos, int size)
-{
- QEMUFileRDMA *r = opaque;
- QEMUFile *f = r->file;
- RDMAContext *rdma = r->rdma;
- size_t remaining = size;
- uint8_t * data = (void *) buf;
- int ret;
-
- CHECK_ERROR_STATE();
-
- /*
- * Push out any writes that
- * we're queued up for VM's ram.
- */
- ret = qemu_rdma_write_flush(f, rdma);
- if (ret < 0) {
- rdma->error_state = ret;
- return ret;
- }
-
- while (remaining) {
- RDMAControlHeader head;
-
- r->len = MIN(remaining, RDMA_SEND_INCREMENT);
- remaining -= r->len;
-
- head.len = r->len;
- head.type = RDMA_CONTROL_QEMU_FILE;
-
- ret = qemu_rdma_exchange_send(rdma, &head, data, NULL, NULL, NULL);
-
- if (ret < 0) {
- rdma->error_state = ret;
- return ret;
- }
-
- data += r->len;
- }
-
- return size;
-}
-
-static size_t qemu_rdma_fill(RDMAContext *rdma, uint8_t *buf,
- int size, int idx)
-{
- size_t len = 0;
-
- if (rdma->wr_data[idx].control_len) {
- DDDPRINTF("RDMA %" PRId64 " of %d bytes already in buffer\n",
- rdma->wr_data[idx].control_len, size);
-
- len = MIN(size, rdma->wr_data[idx].control_len);
- memcpy(buf, rdma->wr_data[idx].control_curr, len);
- rdma->wr_data[idx].control_curr += len;
- rdma->wr_data[idx].control_len -= len;
- }
-
- return len;
-}
-
-/*
- * QEMUFile interface to the control channel.
- * RDMA links don't use bytestreams, so we have to
- * return bytes to QEMUFile opportunistically.
- */
-static int qemu_rdma_get_buffer(void *opaque, uint8_t *buf,
- int64_t pos, int size)
-{
- QEMUFileRDMA *r = opaque;
- RDMAContext *rdma = r->rdma;
- RDMAControlHeader head;
- int ret = 0;
-
- CHECK_ERROR_STATE();
-
- /*
- * First, we hold on to the last SEND message we
- * were given and dish out the bytes until we run
- * out of bytes.
- */
- r->len = qemu_rdma_fill(r->rdma, buf, size, 0);
- if (r->len) {
- return r->len;
- }
-
- /*
- * Once we run out, we block and wait for another
- * SEND message to arrive.
- */
- ret = qemu_rdma_exchange_recv(rdma, &head, RDMA_CONTROL_QEMU_FILE);
-
- if (ret < 0) {
- rdma->error_state = ret;
- return ret;
- }
-
- /*
- * SEND was received with new bytes, now try again.
- */
- return qemu_rdma_fill(r->rdma, buf, size, 0);
-}
-
-/*
- * Block until all the outstanding chunks have been delivered by the hardware.
- */
-static int qemu_rdma_drain_cq(QEMUFile *f, RDMAContext *rdma)
-{
- int ret;
-
- if (qemu_rdma_write_flush(f, rdma) < 0) {
- return -EIO;
- }
-
- while (rdma->nb_sent) {
- ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
- if (ret < 0) {
- fprintf(stderr, "rdma migration: complete polling error!\n");
- return -EIO;
- }
- }
-
- qemu_rdma_unregister_waiting(rdma);
-
- return 0;
-}
-
-static int qemu_rdma_close(void *opaque)
-{
- DPRINTF("Shutting down connection.\n");
- QEMUFileRDMA *r = opaque;
- if (r->rdma) {
- qemu_rdma_cleanup(r->rdma);
- g_free(r->rdma);
- }
- g_free(r);
- return 0;
-}
-
-/*
- * Parameters:
- * @offset == 0 :
- * This means that 'block_offset' is a full virtual address that does not
- * belong to a RAMBlock of the virtual machine and instead
- * represents a private malloc'd memory area that the caller wishes to
- * transfer.
- *
- * @offset != 0 :
- * Offset is an offset to be added to block_offset and used
- * to also lookup the corresponding RAMBlock.
- *
- * @size > 0 :
- * Initiate an transfer this size.
- *
- * @size == 0 :
- * A 'hint' or 'advice' that means that we wish to speculatively
- * and asynchronously unregister this memory. In this case, there is no
- * guarantee that the unregister will actually happen, for example,
- * if the memory is being actively transmitted. Additionally, the memory
- * may be re-registered at any future time if a write within the same
- * chunk was requested again, even if you attempted to unregister it
- * here.
- *
- * @size < 0 : TODO, not yet supported
- * Unregister the memory NOW. This means that the caller does not
- * expect there to be any future RDMA transfers and we just want to clean
- * things up. This is used in case the upper layer owns the memory and
- * cannot wait for qemu_fclose() to occur.
- *
- * @bytes_sent : User-specificed pointer to indicate how many bytes were
- * sent. Usually, this will not be more than a few bytes of
- * the protocol because most transfers are sent asynchronously.
- */
-static size_t qemu_rdma_save_page(QEMUFile *f, void *opaque,
- ram_addr_t block_offset, ram_addr_t offset,
- size_t size, int *bytes_sent)
-{
- QEMUFileRDMA *rfile = opaque;
- RDMAContext *rdma = rfile->rdma;
- int ret;
-
- CHECK_ERROR_STATE();
-
- qemu_fflush(f);
-
- if (size > 0) {
- /*
- * Add this page to the current 'chunk'. If the chunk
- * is full, or the page doen't belong to the current chunk,
- * an actual RDMA write will occur and a new chunk will be formed.
- */
- ret = qemu_rdma_write(f, rdma, block_offset, offset, size);
- if (ret < 0) {
- fprintf(stderr, "rdma migration: write error! %d\n", ret);
- goto err;
- }
-
- /*
- * We always return 1 bytes because the RDMA
- * protocol is completely asynchronous. We do not yet know
- * whether an identified chunk is zero or not because we're
- * waiting for other pages to potentially be merged with
- * the current chunk. So, we have to call qemu_update_position()
- * later on when the actual write occurs.
- */
- if (bytes_sent) {
- *bytes_sent = 1;
- }
- } else {
- uint64_t index, chunk;
-
- /* TODO: Change QEMUFileOps prototype to be signed: size_t => long
- if (size < 0) {
- ret = qemu_rdma_drain_cq(f, rdma);
- if (ret < 0) {
- fprintf(stderr, "rdma: failed to synchronously drain"
- " completion queue before unregistration.\n");
- goto err;
- }
- }
- */
-
- ret = qemu_rdma_search_ram_block(rdma, block_offset,
- offset, size, &index, &chunk);
-
- if (ret) {
- fprintf(stderr, "ram block search failed\n");
- goto err;
- }
-
- qemu_rdma_signal_unregister(rdma, index, chunk, 0);
-
- /*
- * TODO: Synchronous, guaranteed unregistration (should not occur during
- * fast-path). Otherwise, unregisters will process on the next call to
- * qemu_rdma_drain_cq()
- if (size < 0) {
- qemu_rdma_unregister_waiting(rdma);
- }
- */
- }
-
- /*
- * Drain the Completion Queue if possible, but do not block,
- * just poll.
- *
- * If nothing to poll, the end of the iteration will do this
- * again to make sure we don't overflow the request queue.
- */
- while (1) {
- uint64_t wr_id, wr_id_in;
- int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL);
- if (ret < 0) {
- fprintf(stderr, "rdma migration: polling error! %d\n", ret);
- goto err;
- }
-
- wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
-
- if (wr_id == RDMA_WRID_NONE) {
- break;
- }
- }
-
- return RAM_SAVE_CONTROL_DELAYED;
-err:
- rdma->error_state = ret;
- return ret;
-}
-
-static int qemu_rdma_accept(RDMAContext *rdma)
-{
- RDMACapabilities cap;
- struct rdma_conn_param conn_param = {
- .responder_resources = 2,
- .private_data = &cap,
- .private_data_len = sizeof(cap),
- };
- struct rdma_cm_event *cm_event;
- struct ibv_context *verbs;
- int ret = -EINVAL;
- int idx;
-
- ret = rdma_get_cm_event(rdma->channel, &cm_event);
- if (ret) {
- goto err_rdma_dest_wait;
- }
-
- if (cm_event->event != RDMA_CM_EVENT_CONNECT_REQUEST) {
- rdma_ack_cm_event(cm_event);
- goto err_rdma_dest_wait;
- }
-
- memcpy(&cap, cm_event->param.conn.private_data, sizeof(cap));
-
- network_to_caps(&cap);
-
- if (cap.version < 1 || cap.version > RDMA_CONTROL_VERSION_CURRENT) {
- fprintf(stderr, "Unknown source RDMA version: %d, bailing...\n",
- cap.version);
- rdma_ack_cm_event(cm_event);
- goto err_rdma_dest_wait;
- }
-
- /*
- * Respond with only the capabilities this version of QEMU knows about.
- */
- cap.flags &= known_capabilities;
-
- /*
- * Enable the ones that we do know about.
- * Add other checks here as new ones are introduced.
- */
- if (cap.flags & RDMA_CAPABILITY_PIN_ALL) {
- rdma->pin_all = true;
- }
-
- rdma->cm_id = cm_event->id;
- verbs = cm_event->id->verbs;
-
- rdma_ack_cm_event(cm_event);
-
- DPRINTF("Memory pin all: %s\n", rdma->pin_all ? "enabled" : "disabled");
-
- caps_to_network(&cap);
-
- DPRINTF("verbs context after listen: %p\n", verbs);
-
- if (!rdma->verbs) {
- rdma->verbs = verbs;
- } else if (rdma->verbs != verbs) {
- fprintf(stderr, "ibv context not matching %p, %p!\n",
- rdma->verbs, verbs);
- goto err_rdma_dest_wait;
- }
-
- qemu_rdma_dump_id("dest_init", verbs);
-
- ret = qemu_rdma_alloc_pd_cq(rdma);
- if (ret) {
- fprintf(stderr, "rdma migration: error allocating pd and cq!\n");
- goto err_rdma_dest_wait;
- }
-
- ret = qemu_rdma_alloc_qp(rdma);
- if (ret) {
- fprintf(stderr, "rdma migration: error allocating qp!\n");
- goto err_rdma_dest_wait;
- }
-
- ret = qemu_rdma_init_ram_blocks(rdma);
- if (ret) {
- fprintf(stderr, "rdma migration: error initializing ram blocks!\n");
- goto err_rdma_dest_wait;
- }
-
- for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
- ret = qemu_rdma_reg_control(rdma, idx);
- if (ret) {
- fprintf(stderr, "rdma: error registering %d control!\n", idx);
- goto err_rdma_dest_wait;
- }
- }
-
- qemu_set_fd_handler2(rdma->channel->fd, NULL, NULL, NULL, NULL);
-
- ret = rdma_accept(rdma->cm_id, &conn_param);
- if (ret) {
- fprintf(stderr, "rdma_accept returns %d!\n", ret);
- goto err_rdma_dest_wait;
- }
-
- ret = rdma_get_cm_event(rdma->channel, &cm_event);
- if (ret) {
- fprintf(stderr, "rdma_accept get_cm_event failed %d!\n", ret);
- goto err_rdma_dest_wait;
- }
-
- if (cm_event->event != RDMA_CM_EVENT_ESTABLISHED) {
- fprintf(stderr, "rdma_accept not event established!\n");
- rdma_ack_cm_event(cm_event);
- goto err_rdma_dest_wait;
- }
-
- rdma_ack_cm_event(cm_event);
- rdma->connected = true;
-
- ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
- if (ret) {
- fprintf(stderr, "rdma migration: error posting second control recv!\n");
- goto err_rdma_dest_wait;
- }
-
- qemu_rdma_dump_gid("dest_connect", rdma->cm_id);
-
- return 0;
-
-err_rdma_dest_wait:
- rdma->error_state = ret;
- qemu_rdma_cleanup(rdma);
- return ret;
-}
-
-/*
- * During each iteration of the migration, we listen for instructions
- * by the source VM to perform dynamic page registrations before they
- * can perform RDMA operations.
- *
- * We respond with the 'rkey'.
- *
- * Keep doing this until the source tells us to stop.
- */
-static int qemu_rdma_registration_handle(QEMUFile *f, void *opaque,
- uint64_t flags)
-{
- RDMAControlHeader reg_resp = { .len = sizeof(RDMARegisterResult),
- .type = RDMA_CONTROL_REGISTER_RESULT,
- .repeat = 0,
- };
- RDMAControlHeader unreg_resp = { .len = 0,
- .type = RDMA_CONTROL_UNREGISTER_FINISHED,
- .repeat = 0,
- };
- RDMAControlHeader blocks = { .type = RDMA_CONTROL_RAM_BLOCKS_RESULT,
- .repeat = 1 };
- QEMUFileRDMA *rfile = opaque;
- RDMAContext *rdma = rfile->rdma;
- RDMALocalBlocks *local = &rdma->local_ram_blocks;
- RDMAControlHeader head;
- RDMARegister *reg, *registers;
- RDMACompress *comp;
- RDMARegisterResult *reg_result;
- static RDMARegisterResult results[RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE];
- RDMALocalBlock *block;
- void *host_addr;
- int ret = 0;
- int idx = 0;
- int count = 0;
- int i = 0;
-
- CHECK_ERROR_STATE();
-
- do {
- DDDPRINTF("Waiting for next request %" PRIu64 "...\n", flags);
-
- ret = qemu_rdma_exchange_recv(rdma, &head, RDMA_CONTROL_NONE);
-
- if (ret < 0) {
- break;
- }
-
- if (head.repeat > RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE) {
- fprintf(stderr, "rdma: Too many requests in this message (%d)."
- "Bailing.\n", head.repeat);
- ret = -EIO;
- break;
- }
-
- switch (head.type) {
- case RDMA_CONTROL_COMPRESS:
- comp = (RDMACompress *) rdma->wr_data[idx].control_curr;
- network_to_compress(comp);
-
- DDPRINTF("Zapping zero chunk: %" PRId64
- " bytes, index %d, offset %" PRId64 "\n",
- comp->length, comp->block_idx, comp->offset);
- block = &(rdma->local_ram_blocks.block[comp->block_idx]);
-
- host_addr = block->local_host_addr +
- (comp->offset - block->offset);
-
- ram_handle_compressed(host_addr, comp->value, comp->length);
- break;
-
- case RDMA_CONTROL_REGISTER_FINISHED:
- DDDPRINTF("Current registrations complete.\n");
- goto out;
-
- case RDMA_CONTROL_RAM_BLOCKS_REQUEST:
- DPRINTF("Initial setup info requested.\n");
-
- if (rdma->pin_all) {
- ret = qemu_rdma_reg_whole_ram_blocks(rdma);
- if (ret) {
- fprintf(stderr, "rdma migration: error dest "
- "registering ram blocks!\n");
- goto out;
- }
- }
-
- /*
- * Dest uses this to prepare to transmit the RAMBlock descriptions
- * to the source VM after connection setup.
- * Both sides use the "remote" structure to communicate and update
- * their "local" descriptions with what was sent.
- */
- for (i = 0; i < local->nb_blocks; i++) {
- rdma->block[i].remote_host_addr =
- (uint64_t)(local->block[i].local_host_addr);
-
- if (rdma->pin_all) {
- rdma->block[i].remote_rkey = local->block[i].mr->rkey;
- }
-
- rdma->block[i].offset = local->block[i].offset;
- rdma->block[i].length = local->block[i].length;
-
- remote_block_to_network(&rdma->block[i]);
- }
-
- blocks.len = rdma->local_ram_blocks.nb_blocks
- * sizeof(RDMARemoteBlock);
-
-
- ret = qemu_rdma_post_send_control(rdma,
- (uint8_t *) rdma->block, &blocks);
-
- if (ret < 0) {
- fprintf(stderr, "rdma migration: error sending remote info!\n");
- goto out;
- }
-
- break;
- case RDMA_CONTROL_REGISTER_REQUEST:
- DDPRINTF("There are %d registration requests\n", head.repeat);
-
- reg_resp.repeat = head.repeat;
- registers = (RDMARegister *) rdma->wr_data[idx].control_curr;
-
- for (count = 0; count < head.repeat; count++) {
- uint64_t chunk;
- uint8_t *chunk_start, *chunk_end;
-
- reg = ®isters[count];
- network_to_register(reg);
-
- reg_result = &results[count];
-
- DDPRINTF("Registration request (%d): index %d, current_addr %"
- PRIu64 " chunks: %" PRIu64 "\n", count,
- reg->current_index, reg->key.current_addr, reg->chunks);
-
- block = &(rdma->local_ram_blocks.block[reg->current_index]);
- if (block->is_ram_block) {
- host_addr = (block->local_host_addr +
- (reg->key.current_addr - block->offset));
- chunk = ram_chunk_index(block->local_host_addr,
- (uint8_t *) host_addr);
- } else {
- chunk = reg->key.chunk;
- host_addr = block->local_host_addr +
- (reg->key.chunk * (1UL << RDMA_REG_CHUNK_SHIFT));
- }
- chunk_start = ram_chunk_start(block, chunk);
- chunk_end = ram_chunk_end(block, chunk + reg->chunks);
- if (qemu_rdma_register_and_get_keys(rdma, block,
- (uint8_t *)host_addr, NULL, ®_result->rkey,
- chunk, chunk_start, chunk_end)) {
- fprintf(stderr, "cannot get rkey!\n");
- ret = -EINVAL;
- goto out;
- }
-
- reg_result->host_addr = (uint64_t) block->local_host_addr;
-
- DDPRINTF("Registered rkey for this request: %x\n",
- reg_result->rkey);
-
- result_to_network(reg_result);
- }
-
- ret = qemu_rdma_post_send_control(rdma,
- (uint8_t *) results, ®_resp);
-
- if (ret < 0) {
- fprintf(stderr, "Failed to send control buffer!\n");
- goto out;
- }
- break;
- case RDMA_CONTROL_UNREGISTER_REQUEST:
- DDPRINTF("There are %d unregistration requests\n", head.repeat);
- unreg_resp.repeat = head.repeat;
- registers = (RDMARegister *) rdma->wr_data[idx].control_curr;
-
- for (count = 0; count < head.repeat; count++) {
- reg = ®isters[count];
- network_to_register(reg);
-
- DDPRINTF("Unregistration request (%d): "
- " index %d, chunk %" PRIu64 "\n",
- count, reg->current_index, reg->key.chunk);
-
- block = &(rdma->local_ram_blocks.block[reg->current_index]);
-
- ret = ibv_dereg_mr(block->pmr[reg->key.chunk]);
- block->pmr[reg->key.chunk] = NULL;
-
- if (ret != 0) {
- perror("rdma unregistration chunk failed");
- ret = -ret;
- goto out;
- }
-
- rdma->total_registrations--;
-
- DDPRINTF("Unregistered chunk %" PRIu64 " successfully.\n",
- reg->key.chunk);
- }
-
- ret = qemu_rdma_post_send_control(rdma, NULL, &unreg_resp);
-
- if (ret < 0) {
- fprintf(stderr, "Failed to send control buffer!\n");
- goto out;
- }
- break;
- case RDMA_CONTROL_REGISTER_RESULT:
- fprintf(stderr, "Invalid RESULT message at dest.\n");
- ret = -EIO;
- goto out;
- default:
- fprintf(stderr, "Unknown control message %s\n",
- control_desc[head.type]);
- ret = -EIO;
- goto out;
- }
- } while (1);
-out:
- if (ret < 0) {
- rdma->error_state = ret;
- }
- return ret;
-}
-
-static int qemu_rdma_registration_start(QEMUFile *f, void *opaque,
- uint64_t flags)
-{
- QEMUFileRDMA *rfile = opaque;
- RDMAContext *rdma = rfile->rdma;
-
- CHECK_ERROR_STATE();
-
- DDDPRINTF("start section: %" PRIu64 "\n", flags);
- qemu_put_be64(f, RAM_SAVE_FLAG_HOOK);
- qemu_fflush(f);
-
- return 0;
-}
-
-/*
- * Inform dest that dynamic registrations are done for now.
- * First, flush writes, if any.
- */
-static int qemu_rdma_registration_stop(QEMUFile *f, void *opaque,
- uint64_t flags)
-{
- Error *local_err = NULL, **errp = &local_err;
- QEMUFileRDMA *rfile = opaque;
- RDMAContext *rdma = rfile->rdma;
- RDMAControlHeader head = { .len = 0, .repeat = 1 };
- int ret = 0;
-
- CHECK_ERROR_STATE();
-
- qemu_fflush(f);
- ret = qemu_rdma_drain_cq(f, rdma);
-
- if (ret < 0) {
- goto err;
- }
-
- if (flags == RAM_CONTROL_SETUP) {
- RDMAControlHeader resp = {.type = RDMA_CONTROL_RAM_BLOCKS_RESULT };
- RDMALocalBlocks *local = &rdma->local_ram_blocks;
- int reg_result_idx, i, j, nb_remote_blocks;
-
- head.type = RDMA_CONTROL_RAM_BLOCKS_REQUEST;
- DPRINTF("Sending registration setup for ram blocks...\n");
-
- /*
- * Make sure that we parallelize the pinning on both sides.
- * For very large guests, doing this serially takes a really
- * long time, so we have to 'interleave' the pinning locally
- * with the control messages by performing the pinning on this
- * side before we receive the control response from the other
- * side that the pinning has completed.
- */
- ret = qemu_rdma_exchange_send(rdma, &head, NULL, &resp,
- ®_result_idx, rdma->pin_all ?
- qemu_rdma_reg_whole_ram_blocks : NULL);
- if (ret < 0) {
- ERROR(errp, "receiving remote info!");
- return ret;
- }
-
- nb_remote_blocks = resp.len / sizeof(RDMARemoteBlock);
-
- /*
- * The protocol uses two different sets of rkeys (mutually exclusive):
- * 1. One key to represent the virtual address of the entire ram block.
- * (dynamic chunk registration disabled - pin everything with one rkey.)
- * 2. One to represent individual chunks within a ram block.
- * (dynamic chunk registration enabled - pin individual chunks.)
- *
- * Once the capability is successfully negotiated, the destination transmits
- * the keys to use (or sends them later) including the virtual addresses
- * and then propagates the remote ram block descriptions to his local copy.
- */
-
- if (local->nb_blocks != nb_remote_blocks) {
- ERROR(errp, "ram blocks mismatch #1! "
- "Your QEMU command line parameters are probably "
- "not identical on both the source and destination.");
- return -EINVAL;
- }
-
- qemu_rdma_move_header(rdma, reg_result_idx, &resp);
- memcpy(rdma->block,
- rdma->wr_data[reg_result_idx].control_curr, resp.len);
- for (i = 0; i < nb_remote_blocks; i++) {
- network_to_remote_block(&rdma->block[i]);
-
- /* search local ram blocks */
- for (j = 0; j < local->nb_blocks; j++) {
- if (rdma->block[i].offset != local->block[j].offset) {
- continue;
- }
-
- if (rdma->block[i].length != local->block[j].length) {
- ERROR(errp, "ram blocks mismatch #2! "
- "Your QEMU command line parameters are probably "
- "not identical on both the source and destination.");
- return -EINVAL;
- }
- local->block[j].remote_host_addr =
- rdma->block[i].remote_host_addr;
- local->block[j].remote_rkey = rdma->block[i].remote_rkey;
- break;
- }
-
- if (j >= local->nb_blocks) {
- ERROR(errp, "ram blocks mismatch #3! "
- "Your QEMU command line parameters are probably "
- "not identical on both the source and destination.");
- return -EINVAL;
- }
- }
- }
-
- DDDPRINTF("Sending registration finish %" PRIu64 "...\n", flags);
-
- head.type = RDMA_CONTROL_REGISTER_FINISHED;
- ret = qemu_rdma_exchange_send(rdma, &head, NULL, NULL, NULL, NULL);
-
- if (ret < 0) {
- goto err;
- }
-
- return 0;
-err:
- rdma->error_state = ret;
- return ret;
-}
-
-static int qemu_rdma_get_fd(void *opaque)
-{
- QEMUFileRDMA *rfile = opaque;
- RDMAContext *rdma = rfile->rdma;
-
- return rdma->comp_channel->fd;
-}
-
-const QEMUFileOps rdma_read_ops = {
- .get_buffer = qemu_rdma_get_buffer,
- .get_fd = qemu_rdma_get_fd,
- .close = qemu_rdma_close,
- .hook_ram_load = qemu_rdma_registration_handle,
-};
-
-const QEMUFileOps rdma_write_ops = {
- .put_buffer = qemu_rdma_put_buffer,
- .close = qemu_rdma_close,
- .before_ram_iterate = qemu_rdma_registration_start,
- .after_ram_iterate = qemu_rdma_registration_stop,
- .save_page = qemu_rdma_save_page,
-};
-
-static void *qemu_fopen_rdma(RDMAContext *rdma, const char *mode)
-{
- QEMUFileRDMA *r = g_malloc0(sizeof(QEMUFileRDMA));
-
- if (qemu_file_mode_is_not_valid(mode)) {
- return NULL;
- }
-
- r->rdma = rdma;
-
- if (mode[0] == 'w') {
- r->file = qemu_fopen_ops(r, &rdma_write_ops);
- } else {
- r->file = qemu_fopen_ops(r, &rdma_read_ops);
- }
-
- return r->file;
-}
-
-static void rdma_accept_incoming_migration(void *opaque)
-{
- RDMAContext *rdma = opaque;
- int ret;
- QEMUFile *f;
- Error *local_err = NULL, **errp = &local_err;
-
- DPRINTF("Accepting rdma connection...\n");
- ret = qemu_rdma_accept(rdma);
-
- if (ret) {
- ERROR(errp, "RDMA Migration initialization failed!");
- return;
- }
-
- DPRINTF("Accepted migration\n");
-
- f = qemu_fopen_rdma(rdma, "rb");
- if (f == NULL) {
- ERROR(errp, "could not qemu_fopen_rdma!");
- qemu_rdma_cleanup(rdma);
- return;
- }
-
- rdma->migration_started_on_destination = 1;
- process_incoming_migration(f);
-}
-
-void rdma_start_incoming_migration(const char *host_port, Error **errp)
-{
- int ret;
- RDMAContext *rdma;
- Error *local_err = NULL;
-
- DPRINTF("Starting RDMA-based incoming migration\n");
- rdma = qemu_rdma_data_init(host_port, &local_err);
-
- if (rdma == NULL) {
- goto err;
- }
-
- ret = qemu_rdma_dest_init(rdma, &local_err);
-
- if (ret) {
- goto err;
- }
-
- DPRINTF("qemu_rdma_dest_init success\n");
-
- ret = rdma_listen(rdma->listen_id, 5);
-
- if (ret) {
- ERROR(errp, "listening on socket!");
- goto err;
- }
-
- DPRINTF("rdma_listen success\n");
-
- qemu_set_fd_handler2(rdma->channel->fd, NULL,
- rdma_accept_incoming_migration, NULL,
- (void *)(intptr_t) rdma);
- return;
-err:
- error_propagate(errp, local_err);
- g_free(rdma);
-}
-
-void rdma_start_outgoing_migration(void *opaque,
- const char *host_port, Error **errp)
-{
- MigrationState *s = opaque;
- Error *local_err = NULL, **temp = &local_err;
- RDMAContext *rdma = qemu_rdma_data_init(host_port, &local_err);
- int ret = 0;
-
- if (rdma == NULL) {
- ERROR(temp, "Failed to initialize RDMA data structures! %d", ret);
- goto err;
- }
-
- ret = qemu_rdma_source_init(rdma, &local_err,
- s->enabled_capabilities[MIGRATION_CAPABILITY_RDMA_PIN_ALL]);
-
- if (ret) {
- goto err;
- }
-
- DPRINTF("qemu_rdma_source_init success\n");
- ret = qemu_rdma_connect(rdma, &local_err);
-
- if (ret) {
- goto err;
- }
-
- DPRINTF("qemu_rdma_source_connect success\n");
-
- s->file = qemu_fopen_rdma(rdma, "wb");
- migrate_fd_connect(s);
- return;
-err:
- error_propagate(errp, local_err);
- g_free(rdma);
- migrate_fd_error(s);
-}
+++ /dev/null
-/*
- * QEMU live migration
- *
- * Copyright IBM, Corp. 2008
- *
- * Authors:
- * Anthony Liguori <aliguori@us.ibm.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
-
-#include <string.h>
-
-#include "qemu-common.h"
-#include "qemu/error-report.h"
-#include "qemu/sockets.h"
-#include "migration/migration.h"
-#include "migration/qemu-file.h"
-#include "block/block.h"
-#include "qemu/main-loop.h"
-
-//#define DEBUG_MIGRATION_TCP
-
-#ifdef DEBUG_MIGRATION_TCP
-#define DPRINTF(fmt, ...) \
- do { printf("migration-tcp: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
- do { } while (0)
-#endif
-
-static void tcp_wait_for_connect(int fd, Error *err, void *opaque)
-{
- MigrationState *s = opaque;
-
- if (fd < 0) {
- DPRINTF("migrate connect error: %s\n", error_get_pretty(err));
- s->file = NULL;
- migrate_fd_error(s);
- } else {
- DPRINTF("migrate connect success\n");
- s->file = qemu_fopen_socket(fd, "wb");
- migrate_fd_connect(s);
- }
-}
-
-void tcp_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp)
-{
- inet_nonblocking_connect(host_port, tcp_wait_for_connect, s, errp);
-}
-
-static void tcp_accept_incoming_migration(void *opaque)
-{
- struct sockaddr_in addr;
- socklen_t addrlen = sizeof(addr);
- int s = (intptr_t)opaque;
- QEMUFile *f;
- int c, err;
-
- do {
- c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
- err = socket_error();
- } while (c < 0 && err == EINTR);
- qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
- closesocket(s);
-
- DPRINTF("accepted migration\n");
-
- if (c < 0) {
- error_report("could not accept migration connection (%s)",
- strerror(err));
- return;
- }
-
- f = qemu_fopen_socket(c, "rb");
- if (f == NULL) {
- error_report("could not qemu_fopen socket");
- goto out;
- }
-
- process_incoming_migration(f);
- return;
-
-out:
- closesocket(c);
-}
-
-void tcp_start_incoming_migration(const char *host_port, Error **errp)
-{
- int s;
-
- s = inet_listen(host_port, NULL, 256, SOCK_STREAM, 0, errp);
- if (s < 0) {
- return;
- }
-
- qemu_set_fd_handler2(s, NULL, tcp_accept_incoming_migration, NULL,
- (void *)(intptr_t)s);
-}
+++ /dev/null
-/*
- * QEMU live migration via Unix Domain Sockets
- *
- * Copyright Red Hat, Inc. 2009
- *
- * Authors:
- * Chris Lalancette <clalance@redhat.com>
- *
- * This work is licensed under the terms of the GNU GPL, version 2. See
- * the COPYING file in the top-level directory.
- *
- * Contributions after 2012-01-13 are licensed under the terms of the
- * GNU GPL, version 2 or (at your option) any later version.
- */
-
-#include <string.h>
-
-#include "qemu-common.h"
-#include "qemu/error-report.h"
-#include "qemu/sockets.h"
-#include "qemu/main-loop.h"
-#include "migration/migration.h"
-#include "migration/qemu-file.h"
-#include "block/block.h"
-
-//#define DEBUG_MIGRATION_UNIX
-
-#ifdef DEBUG_MIGRATION_UNIX
-#define DPRINTF(fmt, ...) \
- do { printf("migration-unix: " fmt, ## __VA_ARGS__); } while (0)
-#else
-#define DPRINTF(fmt, ...) \
- do { } while (0)
-#endif
-
-static void unix_wait_for_connect(int fd, Error *err, void *opaque)
-{
- MigrationState *s = opaque;
-
- if (fd < 0) {
- DPRINTF("migrate connect error: %s\n", error_get_pretty(err));
- s->file = NULL;
- migrate_fd_error(s);
- } else {
- DPRINTF("migrate connect success\n");
- s->file = qemu_fopen_socket(fd, "wb");
- migrate_fd_connect(s);
- }
-}
-
-void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp)
-{
- unix_nonblocking_connect(path, unix_wait_for_connect, s, errp);
-}
-
-static void unix_accept_incoming_migration(void *opaque)
-{
- struct sockaddr_un addr;
- socklen_t addrlen = sizeof(addr);
- int s = (intptr_t)opaque;
- QEMUFile *f;
- int c, err;
-
- do {
- c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
- err = errno;
- } while (c < 0 && err == EINTR);
- qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
- close(s);
-
- DPRINTF("accepted migration\n");
-
- if (c < 0) {
- error_report("could not accept migration connection (%s)",
- strerror(err));
- return;
- }
-
- f = qemu_fopen_socket(c, "rb");
- if (f == NULL) {
- error_report("could not qemu_fopen socket");
- goto out;
- }
-
- process_incoming_migration(f);
- return;
-
-out:
- close(c);
-}
-
-void unix_start_incoming_migration(const char *path, Error **errp)
-{
- int s;
-
- s = unix_listen(path, NULL, 0, errp);
- if (s < 0) {
- return;
- }
-
- qemu_set_fd_handler2(s, NULL, unix_accept_incoming_migration, NULL,
- (void *)(intptr_t)s);
-}
--- /dev/null
+/*
+ * RDMA protocol and interfaces
+ *
+ * Copyright IBM, Corp. 2010-2013
+ *
+ * Authors:
+ * Michael R. Hines <mrhines@us.ibm.com>
+ * Jiuxing Liu <jl@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or
+ * later. See the COPYING file in the top-level directory.
+ *
+ */
+#include "qemu-common.h"
+#include "migration/migration.h"
+#include "migration/qemu-file.h"
+#include "exec/cpu-common.h"
+#include "qemu/main-loop.h"
+#include "qemu/sockets.h"
+#include "qemu/bitmap.h"
+#include "block/coroutine.h"
+#include <stdio.h>
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+#include <arpa/inet.h>
+#include <string.h>
+#include <rdma/rdma_cma.h>
+
+//#define DEBUG_RDMA
+//#define DEBUG_RDMA_VERBOSE
+//#define DEBUG_RDMA_REALLY_VERBOSE
+
+#ifdef DEBUG_RDMA
+#define DPRINTF(fmt, ...) \
+ do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+#ifdef DEBUG_RDMA_VERBOSE
+#define DDPRINTF(fmt, ...) \
+ do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DDPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+#ifdef DEBUG_RDMA_REALLY_VERBOSE
+#define DDDPRINTF(fmt, ...) \
+ do { printf("rdma: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DDDPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+/*
+ * Print and error on both the Monitor and the Log file.
+ */
+#define ERROR(errp, fmt, ...) \
+ do { \
+ fprintf(stderr, "RDMA ERROR: " fmt "\n", ## __VA_ARGS__); \
+ if (errp && (*(errp) == NULL)) { \
+ error_setg(errp, "RDMA ERROR: " fmt, ## __VA_ARGS__); \
+ } \
+ } while (0)
+
+#define RDMA_RESOLVE_TIMEOUT_MS 10000
+
+/* Do not merge data if larger than this. */
+#define RDMA_MERGE_MAX (2 * 1024 * 1024)
+#define RDMA_SIGNALED_SEND_MAX (RDMA_MERGE_MAX / 4096)
+
+#define RDMA_REG_CHUNK_SHIFT 20 /* 1 MB */
+
+/*
+ * This is only for non-live state being migrated.
+ * Instead of RDMA_WRITE messages, we use RDMA_SEND
+ * messages for that state, which requires a different
+ * delivery design than main memory.
+ */
+#define RDMA_SEND_INCREMENT 32768
+
+/*
+ * Maximum size infiniband SEND message
+ */
+#define RDMA_CONTROL_MAX_BUFFER (512 * 1024)
+#define RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE 4096
+
+#define RDMA_CONTROL_VERSION_CURRENT 1
+/*
+ * Capabilities for negotiation.
+ */
+#define RDMA_CAPABILITY_PIN_ALL 0x01
+
+/*
+ * Add the other flags above to this list of known capabilities
+ * as they are introduced.
+ */
+static uint32_t known_capabilities = RDMA_CAPABILITY_PIN_ALL;
+
+#define CHECK_ERROR_STATE() \
+ do { \
+ if (rdma->error_state) { \
+ if (!rdma->error_reported) { \
+ fprintf(stderr, "RDMA is in an error state waiting migration" \
+ " to abort!\n"); \
+ rdma->error_reported = 1; \
+ } \
+ return rdma->error_state; \
+ } \
+ } while (0);
+
+/*
+ * A work request ID is 64-bits and we split up these bits
+ * into 3 parts:
+ *
+ * bits 0-15 : type of control message, 2^16
+ * bits 16-29: ram block index, 2^14
+ * bits 30-63: ram block chunk number, 2^34
+ *
+ * The last two bit ranges are only used for RDMA writes,
+ * in order to track their completion and potentially
+ * also track unregistration status of the message.
+ */
+#define RDMA_WRID_TYPE_SHIFT 0UL
+#define RDMA_WRID_BLOCK_SHIFT 16UL
+#define RDMA_WRID_CHUNK_SHIFT 30UL
+
+#define RDMA_WRID_TYPE_MASK \
+ ((1UL << RDMA_WRID_BLOCK_SHIFT) - 1UL)
+
+#define RDMA_WRID_BLOCK_MASK \
+ (~RDMA_WRID_TYPE_MASK & ((1UL << RDMA_WRID_CHUNK_SHIFT) - 1UL))
+
+#define RDMA_WRID_CHUNK_MASK (~RDMA_WRID_BLOCK_MASK & ~RDMA_WRID_TYPE_MASK)
+
+/*
+ * RDMA migration protocol:
+ * 1. RDMA Writes (data messages, i.e. RAM)
+ * 2. IB Send/Recv (control channel messages)
+ */
+enum {
+ RDMA_WRID_NONE = 0,
+ RDMA_WRID_RDMA_WRITE = 1,
+ RDMA_WRID_SEND_CONTROL = 2000,
+ RDMA_WRID_RECV_CONTROL = 4000,
+};
+
+const char *wrid_desc[] = {
+ [RDMA_WRID_NONE] = "NONE",
+ [RDMA_WRID_RDMA_WRITE] = "WRITE RDMA",
+ [RDMA_WRID_SEND_CONTROL] = "CONTROL SEND",
+ [RDMA_WRID_RECV_CONTROL] = "CONTROL RECV",
+};
+
+/*
+ * Work request IDs for IB SEND messages only (not RDMA writes).
+ * This is used by the migration protocol to transmit
+ * control messages (such as device state and registration commands)
+ *
+ * We could use more WRs, but we have enough for now.
+ */
+enum {
+ RDMA_WRID_READY = 0,
+ RDMA_WRID_DATA,
+ RDMA_WRID_CONTROL,
+ RDMA_WRID_MAX,
+};
+
+/*
+ * SEND/RECV IB Control Messages.
+ */
+enum {
+ RDMA_CONTROL_NONE = 0,
+ RDMA_CONTROL_ERROR,
+ RDMA_CONTROL_READY, /* ready to receive */
+ RDMA_CONTROL_QEMU_FILE, /* QEMUFile-transmitted bytes */
+ RDMA_CONTROL_RAM_BLOCKS_REQUEST, /* RAMBlock synchronization */
+ RDMA_CONTROL_RAM_BLOCKS_RESULT, /* RAMBlock synchronization */
+ RDMA_CONTROL_COMPRESS, /* page contains repeat values */
+ RDMA_CONTROL_REGISTER_REQUEST, /* dynamic page registration */
+ RDMA_CONTROL_REGISTER_RESULT, /* key to use after registration */
+ RDMA_CONTROL_REGISTER_FINISHED, /* current iteration finished */
+ RDMA_CONTROL_UNREGISTER_REQUEST, /* dynamic UN-registration */
+ RDMA_CONTROL_UNREGISTER_FINISHED, /* unpinning finished */
+};
+
+const char *control_desc[] = {
+ [RDMA_CONTROL_NONE] = "NONE",
+ [RDMA_CONTROL_ERROR] = "ERROR",
+ [RDMA_CONTROL_READY] = "READY",
+ [RDMA_CONTROL_QEMU_FILE] = "QEMU FILE",
+ [RDMA_CONTROL_RAM_BLOCKS_REQUEST] = "RAM BLOCKS REQUEST",
+ [RDMA_CONTROL_RAM_BLOCKS_RESULT] = "RAM BLOCKS RESULT",
+ [RDMA_CONTROL_COMPRESS] = "COMPRESS",
+ [RDMA_CONTROL_REGISTER_REQUEST] = "REGISTER REQUEST",
+ [RDMA_CONTROL_REGISTER_RESULT] = "REGISTER RESULT",
+ [RDMA_CONTROL_REGISTER_FINISHED] = "REGISTER FINISHED",
+ [RDMA_CONTROL_UNREGISTER_REQUEST] = "UNREGISTER REQUEST",
+ [RDMA_CONTROL_UNREGISTER_FINISHED] = "UNREGISTER FINISHED",
+};
+
+/*
+ * Memory and MR structures used to represent an IB Send/Recv work request.
+ * This is *not* used for RDMA writes, only IB Send/Recv.
+ */
+typedef struct {
+ uint8_t control[RDMA_CONTROL_MAX_BUFFER]; /* actual buffer to register */
+ struct ibv_mr *control_mr; /* registration metadata */
+ size_t control_len; /* length of the message */
+ uint8_t *control_curr; /* start of unconsumed bytes */
+} RDMAWorkRequestData;
+
+/*
+ * Negotiate RDMA capabilities during connection-setup time.
+ */
+typedef struct {
+ uint32_t version;
+ uint32_t flags;
+} RDMACapabilities;
+
+static void caps_to_network(RDMACapabilities *cap)
+{
+ cap->version = htonl(cap->version);
+ cap->flags = htonl(cap->flags);
+}
+
+static void network_to_caps(RDMACapabilities *cap)
+{
+ cap->version = ntohl(cap->version);
+ cap->flags = ntohl(cap->flags);
+}
+
+/*
+ * Representation of a RAMBlock from an RDMA perspective.
+ * This is not transmitted, only local.
+ * This and subsequent structures cannot be linked lists
+ * because we're using a single IB message to transmit
+ * the information. It's small anyway, so a list is overkill.
+ */
+typedef struct RDMALocalBlock {
+ uint8_t *local_host_addr; /* local virtual address */
+ uint64_t remote_host_addr; /* remote virtual address */
+ uint64_t offset;
+ uint64_t length;
+ struct ibv_mr **pmr; /* MRs for chunk-level registration */
+ struct ibv_mr *mr; /* MR for non-chunk-level registration */
+ uint32_t *remote_keys; /* rkeys for chunk-level registration */
+ uint32_t remote_rkey; /* rkeys for non-chunk-level registration */
+ int index; /* which block are we */
+ bool is_ram_block;
+ int nb_chunks;
+ unsigned long *transit_bitmap;
+ unsigned long *unregister_bitmap;
+} RDMALocalBlock;
+
+/*
+ * Also represents a RAMblock, but only on the dest.
+ * This gets transmitted by the dest during connection-time
+ * to the source VM and then is used to populate the
+ * corresponding RDMALocalBlock with
+ * the information needed to perform the actual RDMA.
+ */
+typedef struct QEMU_PACKED RDMARemoteBlock {
+ uint64_t remote_host_addr;
+ uint64_t offset;
+ uint64_t length;
+ uint32_t remote_rkey;
+ uint32_t padding;
+} RDMARemoteBlock;
+
+static uint64_t htonll(uint64_t v)
+{
+ union { uint32_t lv[2]; uint64_t llv; } u;
+ u.lv[0] = htonl(v >> 32);
+ u.lv[1] = htonl(v & 0xFFFFFFFFULL);
+ return u.llv;
+}
+
+static uint64_t ntohll(uint64_t v) {
+ union { uint32_t lv[2]; uint64_t llv; } u;
+ u.llv = v;
+ return ((uint64_t)ntohl(u.lv[0]) << 32) | (uint64_t) ntohl(u.lv[1]);
+}
+
+static void remote_block_to_network(RDMARemoteBlock *rb)
+{
+ rb->remote_host_addr = htonll(rb->remote_host_addr);
+ rb->offset = htonll(rb->offset);
+ rb->length = htonll(rb->length);
+ rb->remote_rkey = htonl(rb->remote_rkey);
+}
+
+static void network_to_remote_block(RDMARemoteBlock *rb)
+{
+ rb->remote_host_addr = ntohll(rb->remote_host_addr);
+ rb->offset = ntohll(rb->offset);
+ rb->length = ntohll(rb->length);
+ rb->remote_rkey = ntohl(rb->remote_rkey);
+}
+
+/*
+ * Virtual address of the above structures used for transmitting
+ * the RAMBlock descriptions at connection-time.
+ * This structure is *not* transmitted.
+ */
+typedef struct RDMALocalBlocks {
+ int nb_blocks;
+ bool init; /* main memory init complete */
+ RDMALocalBlock *block;
+} RDMALocalBlocks;
+
+/*
+ * Main data structure for RDMA state.
+ * While there is only one copy of this structure being allocated right now,
+ * this is the place where one would start if you wanted to consider
+ * having more than one RDMA connection open at the same time.
+ */
+typedef struct RDMAContext {
+ char *host;
+ int port;
+
+ RDMAWorkRequestData wr_data[RDMA_WRID_MAX];
+
+ /*
+ * This is used by *_exchange_send() to figure out whether or not
+ * the initial "READY" message has already been received or not.
+ * This is because other functions may potentially poll() and detect
+ * the READY message before send() does, in which case we need to
+ * know if it completed.
+ */
+ int control_ready_expected;
+
+ /* number of outstanding writes */
+ int nb_sent;
+
+ /* store info about current buffer so that we can
+ merge it with future sends */
+ uint64_t current_addr;
+ uint64_t current_length;
+ /* index of ram block the current buffer belongs to */
+ int current_index;
+ /* index of the chunk in the current ram block */
+ int current_chunk;
+
+ bool pin_all;
+
+ /*
+ * infiniband-specific variables for opening the device
+ * and maintaining connection state and so forth.
+ *
+ * cm_id also has ibv_context, rdma_event_channel, and ibv_qp in
+ * cm_id->verbs, cm_id->channel, and cm_id->qp.
+ */
+ struct rdma_cm_id *cm_id; /* connection manager ID */
+ struct rdma_cm_id *listen_id;
+ bool connected;
+
+ struct ibv_context *verbs;
+ struct rdma_event_channel *channel;
+ struct ibv_qp *qp; /* queue pair */
+ struct ibv_comp_channel *comp_channel; /* completion channel */
+ struct ibv_pd *pd; /* protection domain */
+ struct ibv_cq *cq; /* completion queue */
+
+ /*
+ * If a previous write failed (perhaps because of a failed
+ * memory registration, then do not attempt any future work
+ * and remember the error state.
+ */
+ int error_state;
+ int error_reported;
+
+ /*
+ * Description of ram blocks used throughout the code.
+ */
+ RDMALocalBlocks local_ram_blocks;
+ RDMARemoteBlock *block;
+
+ /*
+ * Migration on *destination* started.
+ * Then use coroutine yield function.
+ * Source runs in a thread, so we don't care.
+ */
+ int migration_started_on_destination;
+
+ int total_registrations;
+ int total_writes;
+
+ int unregister_current, unregister_next;
+ uint64_t unregistrations[RDMA_SIGNALED_SEND_MAX];
+
+ GHashTable *blockmap;
+} RDMAContext;
+
+/*
+ * Interface to the rest of the migration call stack.
+ */
+typedef struct QEMUFileRDMA {
+ RDMAContext *rdma;
+ size_t len;
+ void *file;
+} QEMUFileRDMA;
+
+/*
+ * Main structure for IB Send/Recv control messages.
+ * This gets prepended at the beginning of every Send/Recv.
+ */
+typedef struct QEMU_PACKED {
+ uint32_t len; /* Total length of data portion */
+ uint32_t type; /* which control command to perform */
+ uint32_t repeat; /* number of commands in data portion of same type */
+ uint32_t padding;
+} RDMAControlHeader;
+
+static void control_to_network(RDMAControlHeader *control)
+{
+ control->type = htonl(control->type);
+ control->len = htonl(control->len);
+ control->repeat = htonl(control->repeat);
+}
+
+static void network_to_control(RDMAControlHeader *control)
+{
+ control->type = ntohl(control->type);
+ control->len = ntohl(control->len);
+ control->repeat = ntohl(control->repeat);
+}
+
+/*
+ * Register a single Chunk.
+ * Information sent by the source VM to inform the dest
+ * to register an single chunk of memory before we can perform
+ * the actual RDMA operation.
+ */
+typedef struct QEMU_PACKED {
+ union QEMU_PACKED {
+ uint64_t current_addr; /* offset into the ramblock of the chunk */
+ uint64_t chunk; /* chunk to lookup if unregistering */
+ } key;
+ uint32_t current_index; /* which ramblock the chunk belongs to */
+ uint32_t padding;
+ uint64_t chunks; /* how many sequential chunks to register */
+} RDMARegister;
+
+static void register_to_network(RDMARegister *reg)
+{
+ reg->key.current_addr = htonll(reg->key.current_addr);
+ reg->current_index = htonl(reg->current_index);
+ reg->chunks = htonll(reg->chunks);
+}
+
+static void network_to_register(RDMARegister *reg)
+{
+ reg->key.current_addr = ntohll(reg->key.current_addr);
+ reg->current_index = ntohl(reg->current_index);
+ reg->chunks = ntohll(reg->chunks);
+}
+
+typedef struct QEMU_PACKED {
+ uint32_t value; /* if zero, we will madvise() */
+ uint32_t block_idx; /* which ram block index */
+ uint64_t offset; /* where in the remote ramblock this chunk */
+ uint64_t length; /* length of the chunk */
+} RDMACompress;
+
+static void compress_to_network(RDMACompress *comp)
+{
+ comp->value = htonl(comp->value);
+ comp->block_idx = htonl(comp->block_idx);
+ comp->offset = htonll(comp->offset);
+ comp->length = htonll(comp->length);
+}
+
+static void network_to_compress(RDMACompress *comp)
+{
+ comp->value = ntohl(comp->value);
+ comp->block_idx = ntohl(comp->block_idx);
+ comp->offset = ntohll(comp->offset);
+ comp->length = ntohll(comp->length);
+}
+
+/*
+ * The result of the dest's memory registration produces an "rkey"
+ * which the source VM must reference in order to perform
+ * the RDMA operation.
+ */
+typedef struct QEMU_PACKED {
+ uint32_t rkey;
+ uint32_t padding;
+ uint64_t host_addr;
+} RDMARegisterResult;
+
+static void result_to_network(RDMARegisterResult *result)
+{
+ result->rkey = htonl(result->rkey);
+ result->host_addr = htonll(result->host_addr);
+};
+
+static void network_to_result(RDMARegisterResult *result)
+{
+ result->rkey = ntohl(result->rkey);
+ result->host_addr = ntohll(result->host_addr);
+};
+
+const char *print_wrid(int wrid);
+static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
+ uint8_t *data, RDMAControlHeader *resp,
+ int *resp_idx,
+ int (*callback)(RDMAContext *rdma));
+
+static inline uint64_t ram_chunk_index(const uint8_t *start,
+ const uint8_t *host)
+{
+ return ((uintptr_t) host - (uintptr_t) start) >> RDMA_REG_CHUNK_SHIFT;
+}
+
+static inline uint8_t *ram_chunk_start(const RDMALocalBlock *rdma_ram_block,
+ uint64_t i)
+{
+ return (uint8_t *) (((uintptr_t) rdma_ram_block->local_host_addr)
+ + (i << RDMA_REG_CHUNK_SHIFT));
+}
+
+static inline uint8_t *ram_chunk_end(const RDMALocalBlock *rdma_ram_block,
+ uint64_t i)
+{
+ uint8_t *result = ram_chunk_start(rdma_ram_block, i) +
+ (1UL << RDMA_REG_CHUNK_SHIFT);
+
+ if (result > (rdma_ram_block->local_host_addr + rdma_ram_block->length)) {
+ result = rdma_ram_block->local_host_addr + rdma_ram_block->length;
+ }
+
+ return result;
+}
+
+static int __qemu_rdma_add_block(RDMAContext *rdma, void *host_addr,
+ ram_addr_t block_offset, uint64_t length)
+{
+ RDMALocalBlocks *local = &rdma->local_ram_blocks;
+ RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
+ (void *) block_offset);
+ RDMALocalBlock *old = local->block;
+
+ assert(block == NULL);
+
+ local->block = g_malloc0(sizeof(RDMALocalBlock) * (local->nb_blocks + 1));
+
+ if (local->nb_blocks) {
+ int x;
+
+ for (x = 0; x < local->nb_blocks; x++) {
+ g_hash_table_remove(rdma->blockmap, (void *)old[x].offset);
+ g_hash_table_insert(rdma->blockmap, (void *)old[x].offset,
+ &local->block[x]);
+ }
+ memcpy(local->block, old, sizeof(RDMALocalBlock) * local->nb_blocks);
+ g_free(old);
+ }
+
+ block = &local->block[local->nb_blocks];
+
+ block->local_host_addr = host_addr;
+ block->offset = block_offset;
+ block->length = length;
+ block->index = local->nb_blocks;
+ block->nb_chunks = ram_chunk_index(host_addr, host_addr + length) + 1UL;
+ block->transit_bitmap = bitmap_new(block->nb_chunks);
+ bitmap_clear(block->transit_bitmap, 0, block->nb_chunks);
+ block->unregister_bitmap = bitmap_new(block->nb_chunks);
+ bitmap_clear(block->unregister_bitmap, 0, block->nb_chunks);
+ block->remote_keys = g_malloc0(block->nb_chunks * sizeof(uint32_t));
+
+ block->is_ram_block = local->init ? false : true;
+
+ g_hash_table_insert(rdma->blockmap, (void *) block_offset, block);
+
+ DDPRINTF("Added Block: %d, addr: %" PRIu64 ", offset: %" PRIu64
+ " length: %" PRIu64 " end: %" PRIu64 " bits %" PRIu64 " chunks %d\n",
+ local->nb_blocks, (uint64_t) block->local_host_addr, block->offset,
+ block->length, (uint64_t) (block->local_host_addr + block->length),
+ BITS_TO_LONGS(block->nb_chunks) *
+ sizeof(unsigned long) * 8, block->nb_chunks);
+
+ local->nb_blocks++;
+
+ return 0;
+}
+
+/*
+ * Memory regions need to be registered with the device and queue pairs setup
+ * in advanced before the migration starts. This tells us where the RAM blocks
+ * are so that we can register them individually.
+ */
+static void qemu_rdma_init_one_block(void *host_addr,
+ ram_addr_t block_offset, ram_addr_t length, void *opaque)
+{
+ __qemu_rdma_add_block(opaque, host_addr, block_offset, length);
+}
+
+/*
+ * Identify the RAMBlocks and their quantity. They will be references to
+ * identify chunk boundaries inside each RAMBlock and also be referenced
+ * during dynamic page registration.
+ */
+static int qemu_rdma_init_ram_blocks(RDMAContext *rdma)
+{
+ RDMALocalBlocks *local = &rdma->local_ram_blocks;
+
+ assert(rdma->blockmap == NULL);
+ rdma->blockmap = g_hash_table_new(g_direct_hash, g_direct_equal);
+ memset(local, 0, sizeof *local);
+ qemu_ram_foreach_block(qemu_rdma_init_one_block, rdma);
+ DPRINTF("Allocated %d local ram block structures\n", local->nb_blocks);
+ rdma->block = (RDMARemoteBlock *) g_malloc0(sizeof(RDMARemoteBlock) *
+ rdma->local_ram_blocks.nb_blocks);
+ local->init = true;
+ return 0;
+}
+
+static int __qemu_rdma_delete_block(RDMAContext *rdma, ram_addr_t block_offset)
+{
+ RDMALocalBlocks *local = &rdma->local_ram_blocks;
+ RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
+ (void *) block_offset);
+ RDMALocalBlock *old = local->block;
+ int x;
+
+ assert(block);
+
+ if (block->pmr) {
+ int j;
+
+ for (j = 0; j < block->nb_chunks; j++) {
+ if (!block->pmr[j]) {
+ continue;
+ }
+ ibv_dereg_mr(block->pmr[j]);
+ rdma->total_registrations--;
+ }
+ g_free(block->pmr);
+ block->pmr = NULL;
+ }
+
+ if (block->mr) {
+ ibv_dereg_mr(block->mr);
+ rdma->total_registrations--;
+ block->mr = NULL;
+ }
+
+ g_free(block->transit_bitmap);
+ block->transit_bitmap = NULL;
+
+ g_free(block->unregister_bitmap);
+ block->unregister_bitmap = NULL;
+
+ g_free(block->remote_keys);
+ block->remote_keys = NULL;
+
+ for (x = 0; x < local->nb_blocks; x++) {
+ g_hash_table_remove(rdma->blockmap, (void *)old[x].offset);
+ }
+
+ if (local->nb_blocks > 1) {
+
+ local->block = g_malloc0(sizeof(RDMALocalBlock) *
+ (local->nb_blocks - 1));
+
+ if (block->index) {
+ memcpy(local->block, old, sizeof(RDMALocalBlock) * block->index);
+ }
+
+ if (block->index < (local->nb_blocks - 1)) {
+ memcpy(local->block + block->index, old + (block->index + 1),
+ sizeof(RDMALocalBlock) *
+ (local->nb_blocks - (block->index + 1)));
+ }
+ } else {
+ assert(block == local->block);
+ local->block = NULL;
+ }
+
+ DDPRINTF("Deleted Block: %d, addr: %" PRIu64 ", offset: %" PRIu64
+ " length: %" PRIu64 " end: %" PRIu64 " bits %" PRIu64 " chunks %d\n",
+ local->nb_blocks, (uint64_t) block->local_host_addr, block->offset,
+ block->length, (uint64_t) (block->local_host_addr + block->length),
+ BITS_TO_LONGS(block->nb_chunks) *
+ sizeof(unsigned long) * 8, block->nb_chunks);
+
+ g_free(old);
+
+ local->nb_blocks--;
+
+ if (local->nb_blocks) {
+ for (x = 0; x < local->nb_blocks; x++) {
+ g_hash_table_insert(rdma->blockmap, (void *)local->block[x].offset,
+ &local->block[x]);
+ }
+ }
+
+ return 0;
+}
+
+/*
+ * Put in the log file which RDMA device was opened and the details
+ * associated with that device.
+ */
+static void qemu_rdma_dump_id(const char *who, struct ibv_context *verbs)
+{
+ struct ibv_port_attr port;
+
+ if (ibv_query_port(verbs, 1, &port)) {
+ fprintf(stderr, "FAILED TO QUERY PORT INFORMATION!\n");
+ return;
+ }
+
+ printf("%s RDMA Device opened: kernel name %s "
+ "uverbs device name %s, "
+ "infiniband_verbs class device path %s, "
+ "infiniband class device path %s, "
+ "transport: (%d) %s\n",
+ who,
+ verbs->device->name,
+ verbs->device->dev_name,
+ verbs->device->dev_path,
+ verbs->device->ibdev_path,
+ port.link_layer,
+ (port.link_layer == IBV_LINK_LAYER_INFINIBAND) ? "Infiniband" :
+ ((port.link_layer == IBV_LINK_LAYER_ETHERNET)
+ ? "Ethernet" : "Unknown"));
+}
+
+/*
+ * Put in the log file the RDMA gid addressing information,
+ * useful for folks who have trouble understanding the
+ * RDMA device hierarchy in the kernel.
+ */
+static void qemu_rdma_dump_gid(const char *who, struct rdma_cm_id *id)
+{
+ char sgid[33];
+ char dgid[33];
+ inet_ntop(AF_INET6, &id->route.addr.addr.ibaddr.sgid, sgid, sizeof sgid);
+ inet_ntop(AF_INET6, &id->route.addr.addr.ibaddr.dgid, dgid, sizeof dgid);
+ DPRINTF("%s Source GID: %s, Dest GID: %s\n", who, sgid, dgid);
+}
+
+/*
+ * As of now, IPv6 over RoCE / iWARP is not supported by linux.
+ * We will try the next addrinfo struct, and fail if there are
+ * no other valid addresses to bind against.
+ *
+ * If user is listening on '[::]', then we will not have a opened a device
+ * yet and have no way of verifying if the device is RoCE or not.
+ *
+ * In this case, the source VM will throw an error for ALL types of
+ * connections (both IPv4 and IPv6) if the destination machine does not have
+ * a regular infiniband network available for use.
+ *
+ * The only way to guarantee that an error is thrown for broken kernels is
+ * for the management software to choose a *specific* interface at bind time
+ * and validate what time of hardware it is.
+ *
+ * Unfortunately, this puts the user in a fix:
+ *
+ * If the source VM connects with an IPv4 address without knowing that the
+ * destination has bound to '[::]' the migration will unconditionally fail
+ * unless the management software is explicitly listening on the the IPv4
+ * address while using a RoCE-based device.
+ *
+ * If the source VM connects with an IPv6 address, then we're OK because we can
+ * throw an error on the source (and similarly on the destination).
+ *
+ * But in mixed environments, this will be broken for a while until it is fixed
+ * inside linux.
+ *
+ * We do provide a *tiny* bit of help in this function: We can list all of the
+ * devices in the system and check to see if all the devices are RoCE or
+ * Infiniband.
+ *
+ * If we detect that we have a *pure* RoCE environment, then we can safely
+ * thrown an error even if the management software has specified '[::]' as the
+ * bind address.
+ *
+ * However, if there is are multiple hetergeneous devices, then we cannot make
+ * this assumption and the user just has to be sure they know what they are
+ * doing.
+ *
+ * Patches are being reviewed on linux-rdma.
+ */
+static int qemu_rdma_broken_ipv6_kernel(Error **errp, struct ibv_context *verbs)
+{
+ struct ibv_port_attr port_attr;
+
+ /* This bug only exists in linux, to our knowledge. */
+#ifdef CONFIG_LINUX
+
+ /*
+ * Verbs are only NULL if management has bound to '[::]'.
+ *
+ * Let's iterate through all the devices and see if there any pure IB
+ * devices (non-ethernet).
+ *
+ * If not, then we can safely proceed with the migration.
+ * Otherwise, there are no guarantees until the bug is fixed in linux.
+ */
+ if (!verbs) {
+ int num_devices, x;
+ struct ibv_device ** dev_list = ibv_get_device_list(&num_devices);
+ bool roce_found = false;
+ bool ib_found = false;
+
+ for (x = 0; x < num_devices; x++) {
+ verbs = ibv_open_device(dev_list[x]);
+
+ if (ibv_query_port(verbs, 1, &port_attr)) {
+ ibv_close_device(verbs);
+ ERROR(errp, "Could not query initial IB port");
+ return -EINVAL;
+ }
+
+ if (port_attr.link_layer == IBV_LINK_LAYER_INFINIBAND) {
+ ib_found = true;
+ } else if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) {
+ roce_found = true;
+ }
+
+ ibv_close_device(verbs);
+
+ }
+
+ if (roce_found) {
+ if (ib_found) {
+ fprintf(stderr, "WARN: migrations may fail:"
+ " IPv6 over RoCE / iWARP in linux"
+ " is broken. But since you appear to have a"
+ " mixed RoCE / IB environment, be sure to only"
+ " migrate over the IB fabric until the kernel "
+ " fixes the bug.\n");
+ } else {
+ ERROR(errp, "You only have RoCE / iWARP devices in your systems"
+ " and your management software has specified '[::]'"
+ ", but IPv6 over RoCE / iWARP is not supported in Linux.");
+ return -ENONET;
+ }
+ }
+
+ return 0;
+ }
+
+ /*
+ * If we have a verbs context, that means that some other than '[::]' was
+ * used by the management software for binding. In which case we can actually
+ * warn the user about a potential broken kernel;
+ */
+
+ /* IB ports start with 1, not 0 */
+ if (ibv_query_port(verbs, 1, &port_attr)) {
+ ERROR(errp, "Could not query initial IB port");
+ return -EINVAL;
+ }
+
+ if (port_attr.link_layer == IBV_LINK_LAYER_ETHERNET) {
+ ERROR(errp, "Linux kernel's RoCE / iWARP does not support IPv6 "
+ "(but patches on linux-rdma in progress)");
+ return -ENONET;
+ }
+
+#endif
+
+ return 0;
+}
+
+/*
+ * Figure out which RDMA device corresponds to the requested IP hostname
+ * Also create the initial connection manager identifiers for opening
+ * the connection.
+ */
+static int qemu_rdma_resolve_host(RDMAContext *rdma, Error **errp)
+{
+ int ret;
+ struct rdma_addrinfo *res;
+ char port_str[16];
+ struct rdma_cm_event *cm_event;
+ char ip[40] = "unknown";
+ struct rdma_addrinfo *e;
+
+ if (rdma->host == NULL || !strcmp(rdma->host, "")) {
+ ERROR(errp, "RDMA hostname has not been set");
+ return -EINVAL;
+ }
+
+ /* create CM channel */
+ rdma->channel = rdma_create_event_channel();
+ if (!rdma->channel) {
+ ERROR(errp, "could not create CM channel");
+ return -EINVAL;
+ }
+
+ /* create CM id */
+ ret = rdma_create_id(rdma->channel, &rdma->cm_id, NULL, RDMA_PS_TCP);
+ if (ret) {
+ ERROR(errp, "could not create channel id");
+ goto err_resolve_create_id;
+ }
+
+ snprintf(port_str, 16, "%d", rdma->port);
+ port_str[15] = '\0';
+
+ ret = rdma_getaddrinfo(rdma->host, port_str, NULL, &res);
+ if (ret < 0) {
+ ERROR(errp, "could not rdma_getaddrinfo address %s", rdma->host);
+ goto err_resolve_get_addr;
+ }
+
+ for (e = res; e != NULL; e = e->ai_next) {
+ inet_ntop(e->ai_family,
+ &((struct sockaddr_in *) e->ai_dst_addr)->sin_addr, ip, sizeof ip);
+ DPRINTF("Trying %s => %s\n", rdma->host, ip);
+
+ ret = rdma_resolve_addr(rdma->cm_id, NULL, e->ai_dst_addr,
+ RDMA_RESOLVE_TIMEOUT_MS);
+ if (!ret) {
+ if (e->ai_family == AF_INET6) {
+ ret = qemu_rdma_broken_ipv6_kernel(errp, rdma->cm_id->verbs);
+ if (ret) {
+ continue;
+ }
+ }
+ goto route;
+ }
+ }
+
+ ERROR(errp, "could not resolve address %s", rdma->host);
+ goto err_resolve_get_addr;
+
+route:
+ qemu_rdma_dump_gid("source_resolve_addr", rdma->cm_id);
+
+ ret = rdma_get_cm_event(rdma->channel, &cm_event);
+ if (ret) {
+ ERROR(errp, "could not perform event_addr_resolved");
+ goto err_resolve_get_addr;
+ }
+
+ if (cm_event->event != RDMA_CM_EVENT_ADDR_RESOLVED) {
+ ERROR(errp, "result not equal to event_addr_resolved %s",
+ rdma_event_str(cm_event->event));
+ perror("rdma_resolve_addr");
+ rdma_ack_cm_event(cm_event);
+ ret = -EINVAL;
+ goto err_resolve_get_addr;
+ }
+ rdma_ack_cm_event(cm_event);
+
+ /* resolve route */
+ ret = rdma_resolve_route(rdma->cm_id, RDMA_RESOLVE_TIMEOUT_MS);
+ if (ret) {
+ ERROR(errp, "could not resolve rdma route");
+ goto err_resolve_get_addr;
+ }
+
+ ret = rdma_get_cm_event(rdma->channel, &cm_event);
+ if (ret) {
+ ERROR(errp, "could not perform event_route_resolved");
+ goto err_resolve_get_addr;
+ }
+ if (cm_event->event != RDMA_CM_EVENT_ROUTE_RESOLVED) {
+ ERROR(errp, "result not equal to event_route_resolved: %s",
+ rdma_event_str(cm_event->event));
+ rdma_ack_cm_event(cm_event);
+ ret = -EINVAL;
+ goto err_resolve_get_addr;
+ }
+ rdma_ack_cm_event(cm_event);
+ rdma->verbs = rdma->cm_id->verbs;
+ qemu_rdma_dump_id("source_resolve_host", rdma->cm_id->verbs);
+ qemu_rdma_dump_gid("source_resolve_host", rdma->cm_id);
+ return 0;
+
+err_resolve_get_addr:
+ rdma_destroy_id(rdma->cm_id);
+ rdma->cm_id = NULL;
+err_resolve_create_id:
+ rdma_destroy_event_channel(rdma->channel);
+ rdma->channel = NULL;
+ return ret;
+}
+
+/*
+ * Create protection domain and completion queues
+ */
+static int qemu_rdma_alloc_pd_cq(RDMAContext *rdma)
+{
+ /* allocate pd */
+ rdma->pd = ibv_alloc_pd(rdma->verbs);
+ if (!rdma->pd) {
+ fprintf(stderr, "failed to allocate protection domain\n");
+ return -1;
+ }
+
+ /* create completion channel */
+ rdma->comp_channel = ibv_create_comp_channel(rdma->verbs);
+ if (!rdma->comp_channel) {
+ fprintf(stderr, "failed to allocate completion channel\n");
+ goto err_alloc_pd_cq;
+ }
+
+ /*
+ * Completion queue can be filled by both read and write work requests,
+ * so must reflect the sum of both possible queue sizes.
+ */
+ rdma->cq = ibv_create_cq(rdma->verbs, (RDMA_SIGNALED_SEND_MAX * 3),
+ NULL, rdma->comp_channel, 0);
+ if (!rdma->cq) {
+ fprintf(stderr, "failed to allocate completion queue\n");
+ goto err_alloc_pd_cq;
+ }
+
+ return 0;
+
+err_alloc_pd_cq:
+ if (rdma->pd) {
+ ibv_dealloc_pd(rdma->pd);
+ }
+ if (rdma->comp_channel) {
+ ibv_destroy_comp_channel(rdma->comp_channel);
+ }
+ rdma->pd = NULL;
+ rdma->comp_channel = NULL;
+ return -1;
+
+}
+
+/*
+ * Create queue pairs.
+ */
+static int qemu_rdma_alloc_qp(RDMAContext *rdma)
+{
+ struct ibv_qp_init_attr attr = { 0 };
+ int ret;
+
+ attr.cap.max_send_wr = RDMA_SIGNALED_SEND_MAX;
+ attr.cap.max_recv_wr = 3;
+ attr.cap.max_send_sge = 1;
+ attr.cap.max_recv_sge = 1;
+ attr.send_cq = rdma->cq;
+ attr.recv_cq = rdma->cq;
+ attr.qp_type = IBV_QPT_RC;
+
+ ret = rdma_create_qp(rdma->cm_id, rdma->pd, &attr);
+ if (ret) {
+ return -1;
+ }
+
+ rdma->qp = rdma->cm_id->qp;
+ return 0;
+}
+
+static int qemu_rdma_reg_whole_ram_blocks(RDMAContext *rdma)
+{
+ int i;
+ RDMALocalBlocks *local = &rdma->local_ram_blocks;
+
+ for (i = 0; i < local->nb_blocks; i++) {
+ local->block[i].mr =
+ ibv_reg_mr(rdma->pd,
+ local->block[i].local_host_addr,
+ local->block[i].length,
+ IBV_ACCESS_LOCAL_WRITE |
+ IBV_ACCESS_REMOTE_WRITE
+ );
+ if (!local->block[i].mr) {
+ perror("Failed to register local dest ram block!\n");
+ break;
+ }
+ rdma->total_registrations++;
+ }
+
+ if (i >= local->nb_blocks) {
+ return 0;
+ }
+
+ for (i--; i >= 0; i--) {
+ ibv_dereg_mr(local->block[i].mr);
+ rdma->total_registrations--;
+ }
+
+ return -1;
+
+}
+
+/*
+ * Find the ram block that corresponds to the page requested to be
+ * transmitted by QEMU.
+ *
+ * Once the block is found, also identify which 'chunk' within that
+ * block that the page belongs to.
+ *
+ * This search cannot fail or the migration will fail.
+ */
+static int qemu_rdma_search_ram_block(RDMAContext *rdma,
+ uint64_t block_offset,
+ uint64_t offset,
+ uint64_t length,
+ uint64_t *block_index,
+ uint64_t *chunk_index)
+{
+ uint64_t current_addr = block_offset + offset;
+ RDMALocalBlock *block = g_hash_table_lookup(rdma->blockmap,
+ (void *) block_offset);
+ assert(block);
+ assert(current_addr >= block->offset);
+ assert((current_addr + length) <= (block->offset + block->length));
+
+ *block_index = block->index;
+ *chunk_index = ram_chunk_index(block->local_host_addr,
+ block->local_host_addr + (current_addr - block->offset));
+
+ return 0;
+}
+
+/*
+ * Register a chunk with IB. If the chunk was already registered
+ * previously, then skip.
+ *
+ * Also return the keys associated with the registration needed
+ * to perform the actual RDMA operation.
+ */
+static int qemu_rdma_register_and_get_keys(RDMAContext *rdma,
+ RDMALocalBlock *block, uint8_t *host_addr,
+ uint32_t *lkey, uint32_t *rkey, int chunk,
+ uint8_t *chunk_start, uint8_t *chunk_end)
+{
+ if (block->mr) {
+ if (lkey) {
+ *lkey = block->mr->lkey;
+ }
+ if (rkey) {
+ *rkey = block->mr->rkey;
+ }
+ return 0;
+ }
+
+ /* allocate memory to store chunk MRs */
+ if (!block->pmr) {
+ block->pmr = g_malloc0(block->nb_chunks * sizeof(struct ibv_mr *));
+ if (!block->pmr) {
+ return -1;
+ }
+ }
+
+ /*
+ * If 'rkey', then we're the destination, so grant access to the source.
+ *
+ * If 'lkey', then we're the source VM, so grant access only to ourselves.
+ */
+ if (!block->pmr[chunk]) {
+ uint64_t len = chunk_end - chunk_start;
+
+ DDPRINTF("Registering %" PRIu64 " bytes @ %p\n",
+ len, chunk_start);
+
+ block->pmr[chunk] = ibv_reg_mr(rdma->pd,
+ chunk_start, len,
+ (rkey ? (IBV_ACCESS_LOCAL_WRITE |
+ IBV_ACCESS_REMOTE_WRITE) : 0));
+
+ if (!block->pmr[chunk]) {
+ perror("Failed to register chunk!");
+ fprintf(stderr, "Chunk details: block: %d chunk index %d"
+ " start %" PRIu64 " end %" PRIu64 " host %" PRIu64
+ " local %" PRIu64 " registrations: %d\n",
+ block->index, chunk, (uint64_t) chunk_start,
+ (uint64_t) chunk_end, (uint64_t) host_addr,
+ (uint64_t) block->local_host_addr,
+ rdma->total_registrations);
+ return -1;
+ }
+ rdma->total_registrations++;
+ }
+
+ if (lkey) {
+ *lkey = block->pmr[chunk]->lkey;
+ }
+ if (rkey) {
+ *rkey = block->pmr[chunk]->rkey;
+ }
+ return 0;
+}
+
+/*
+ * Register (at connection time) the memory used for control
+ * channel messages.
+ */
+static int qemu_rdma_reg_control(RDMAContext *rdma, int idx)
+{
+ rdma->wr_data[idx].control_mr = ibv_reg_mr(rdma->pd,
+ rdma->wr_data[idx].control, RDMA_CONTROL_MAX_BUFFER,
+ IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE);
+ if (rdma->wr_data[idx].control_mr) {
+ rdma->total_registrations++;
+ return 0;
+ }
+ fprintf(stderr, "qemu_rdma_reg_control failed!\n");
+ return -1;
+}
+
+const char *print_wrid(int wrid)
+{
+ if (wrid >= RDMA_WRID_RECV_CONTROL) {
+ return wrid_desc[RDMA_WRID_RECV_CONTROL];
+ }
+ return wrid_desc[wrid];
+}
+
+/*
+ * RDMA requires memory registration (mlock/pinning), but this is not good for
+ * overcommitment.
+ *
+ * In preparation for the future where LRU information or workload-specific
+ * writable writable working set memory access behavior is available to QEMU
+ * it would be nice to have in place the ability to UN-register/UN-pin
+ * particular memory regions from the RDMA hardware when it is determine that
+ * those regions of memory will likely not be accessed again in the near future.
+ *
+ * While we do not yet have such information right now, the following
+ * compile-time option allows us to perform a non-optimized version of this
+ * behavior.
+ *
+ * By uncommenting this option, you will cause *all* RDMA transfers to be
+ * unregistered immediately after the transfer completes on both sides of the
+ * connection. This has no effect in 'rdma-pin-all' mode, only regular mode.
+ *
+ * This will have a terrible impact on migration performance, so until future
+ * workload information or LRU information is available, do not attempt to use
+ * this feature except for basic testing.
+ */
+//#define RDMA_UNREGISTRATION_EXAMPLE
+
+/*
+ * Perform a non-optimized memory unregistration after every transfer
+ * for demonsration purposes, only if pin-all is not requested.
+ *
+ * Potential optimizations:
+ * 1. Start a new thread to run this function continuously
+ - for bit clearing
+ - and for receipt of unregister messages
+ * 2. Use an LRU.
+ * 3. Use workload hints.
+ */
+static int qemu_rdma_unregister_waiting(RDMAContext *rdma)
+{
+ while (rdma->unregistrations[rdma->unregister_current]) {
+ int ret;
+ uint64_t wr_id = rdma->unregistrations[rdma->unregister_current];
+ uint64_t chunk =
+ (wr_id & RDMA_WRID_CHUNK_MASK) >> RDMA_WRID_CHUNK_SHIFT;
+ uint64_t index =
+ (wr_id & RDMA_WRID_BLOCK_MASK) >> RDMA_WRID_BLOCK_SHIFT;
+ RDMALocalBlock *block =
+ &(rdma->local_ram_blocks.block[index]);
+ RDMARegister reg = { .current_index = index };
+ RDMAControlHeader resp = { .type = RDMA_CONTROL_UNREGISTER_FINISHED,
+ };
+ RDMAControlHeader head = { .len = sizeof(RDMARegister),
+ .type = RDMA_CONTROL_UNREGISTER_REQUEST,
+ .repeat = 1,
+ };
+
+ DDPRINTF("Processing unregister for chunk: %" PRIu64
+ " at position %d\n", chunk, rdma->unregister_current);
+
+ rdma->unregistrations[rdma->unregister_current] = 0;
+ rdma->unregister_current++;
+
+ if (rdma->unregister_current == RDMA_SIGNALED_SEND_MAX) {
+ rdma->unregister_current = 0;
+ }
+
+
+ /*
+ * Unregistration is speculative (because migration is single-threaded
+ * and we cannot break the protocol's inifinband message ordering).
+ * Thus, if the memory is currently being used for transmission,
+ * then abort the attempt to unregister and try again
+ * later the next time a completion is received for this memory.
+ */
+ clear_bit(chunk, block->unregister_bitmap);
+
+ if (test_bit(chunk, block->transit_bitmap)) {
+ DDPRINTF("Cannot unregister inflight chunk: %" PRIu64 "\n", chunk);
+ continue;
+ }
+
+ DDPRINTF("Sending unregister for chunk: %" PRIu64 "\n", chunk);
+
+ ret = ibv_dereg_mr(block->pmr[chunk]);
+ block->pmr[chunk] = NULL;
+ block->remote_keys[chunk] = 0;
+
+ if (ret != 0) {
+ perror("unregistration chunk failed");
+ return -ret;
+ }
+ rdma->total_registrations--;
+
+ reg.key.chunk = chunk;
+ register_to_network(®);
+ ret = qemu_rdma_exchange_send(rdma, &head, (uint8_t *) ®,
+ &resp, NULL, NULL);
+ if (ret < 0) {
+ return ret;
+ }
+
+ DDPRINTF("Unregister for chunk: %" PRIu64 " complete.\n", chunk);
+ }
+
+ return 0;
+}
+
+static uint64_t qemu_rdma_make_wrid(uint64_t wr_id, uint64_t index,
+ uint64_t chunk)
+{
+ uint64_t result = wr_id & RDMA_WRID_TYPE_MASK;
+
+ result |= (index << RDMA_WRID_BLOCK_SHIFT);
+ result |= (chunk << RDMA_WRID_CHUNK_SHIFT);
+
+ return result;
+}
+
+/*
+ * Set bit for unregistration in the next iteration.
+ * We cannot transmit right here, but will unpin later.
+ */
+static void qemu_rdma_signal_unregister(RDMAContext *rdma, uint64_t index,
+ uint64_t chunk, uint64_t wr_id)
+{
+ if (rdma->unregistrations[rdma->unregister_next] != 0) {
+ fprintf(stderr, "rdma migration: queue is full!\n");
+ } else {
+ RDMALocalBlock *block = &(rdma->local_ram_blocks.block[index]);
+
+ if (!test_and_set_bit(chunk, block->unregister_bitmap)) {
+ DDPRINTF("Appending unregister chunk %" PRIu64
+ " at position %d\n", chunk, rdma->unregister_next);
+
+ rdma->unregistrations[rdma->unregister_next++] =
+ qemu_rdma_make_wrid(wr_id, index, chunk);
+
+ if (rdma->unregister_next == RDMA_SIGNALED_SEND_MAX) {
+ rdma->unregister_next = 0;
+ }
+ } else {
+ DDPRINTF("Unregister chunk %" PRIu64 " already in queue.\n",
+ chunk);
+ }
+ }
+}
+
+/*
+ * Consult the connection manager to see a work request
+ * (of any kind) has completed.
+ * Return the work request ID that completed.
+ */
+static uint64_t qemu_rdma_poll(RDMAContext *rdma, uint64_t *wr_id_out,
+ uint32_t *byte_len)
+{
+ int ret;
+ struct ibv_wc wc;
+ uint64_t wr_id;
+
+ ret = ibv_poll_cq(rdma->cq, 1, &wc);
+
+ if (!ret) {
+ *wr_id_out = RDMA_WRID_NONE;
+ return 0;
+ }
+
+ if (ret < 0) {
+ fprintf(stderr, "ibv_poll_cq return %d!\n", ret);
+ return ret;
+ }
+
+ wr_id = wc.wr_id & RDMA_WRID_TYPE_MASK;
+
+ if (wc.status != IBV_WC_SUCCESS) {
+ fprintf(stderr, "ibv_poll_cq wc.status=%d %s!\n",
+ wc.status, ibv_wc_status_str(wc.status));
+ fprintf(stderr, "ibv_poll_cq wrid=%s!\n", wrid_desc[wr_id]);
+
+ return -1;
+ }
+
+ if (rdma->control_ready_expected &&
+ (wr_id >= RDMA_WRID_RECV_CONTROL)) {
+ DDDPRINTF("completion %s #%" PRId64 " received (%" PRId64 ")"
+ " left %d\n", wrid_desc[RDMA_WRID_RECV_CONTROL],
+ wr_id - RDMA_WRID_RECV_CONTROL, wr_id, rdma->nb_sent);
+ rdma->control_ready_expected = 0;
+ }
+
+ if (wr_id == RDMA_WRID_RDMA_WRITE) {
+ uint64_t chunk =
+ (wc.wr_id & RDMA_WRID_CHUNK_MASK) >> RDMA_WRID_CHUNK_SHIFT;
+ uint64_t index =
+ (wc.wr_id & RDMA_WRID_BLOCK_MASK) >> RDMA_WRID_BLOCK_SHIFT;
+ RDMALocalBlock *block = &(rdma->local_ram_blocks.block[index]);
+
+ DDDPRINTF("completions %s (%" PRId64 ") left %d, "
+ "block %" PRIu64 ", chunk: %" PRIu64 " %p %p\n",
+ print_wrid(wr_id), wr_id, rdma->nb_sent, index, chunk,
+ block->local_host_addr, (void *)block->remote_host_addr);
+
+ clear_bit(chunk, block->transit_bitmap);
+
+ if (rdma->nb_sent > 0) {
+ rdma->nb_sent--;
+ }
+
+ if (!rdma->pin_all) {
+ /*
+ * FYI: If one wanted to signal a specific chunk to be unregistered
+ * using LRU or workload-specific information, this is the function
+ * you would call to do so. That chunk would then get asynchronously
+ * unregistered later.
+ */
+#ifdef RDMA_UNREGISTRATION_EXAMPLE
+ qemu_rdma_signal_unregister(rdma, index, chunk, wc.wr_id);
+#endif
+ }
+ } else {
+ DDDPRINTF("other completion %s (%" PRId64 ") received left %d\n",
+ print_wrid(wr_id), wr_id, rdma->nb_sent);
+ }
+
+ *wr_id_out = wc.wr_id;
+ if (byte_len) {
+ *byte_len = wc.byte_len;
+ }
+
+ return 0;
+}
+
+/*
+ * Block until the next work request has completed.
+ *
+ * First poll to see if a work request has already completed,
+ * otherwise block.
+ *
+ * If we encounter completed work requests for IDs other than
+ * the one we're interested in, then that's generally an error.
+ *
+ * The only exception is actual RDMA Write completions. These
+ * completions only need to be recorded, but do not actually
+ * need further processing.
+ */
+static int qemu_rdma_block_for_wrid(RDMAContext *rdma, int wrid_requested,
+ uint32_t *byte_len)
+{
+ int num_cq_events = 0, ret = 0;
+ struct ibv_cq *cq;
+ void *cq_ctx;
+ uint64_t wr_id = RDMA_WRID_NONE, wr_id_in;
+
+ if (ibv_req_notify_cq(rdma->cq, 0)) {
+ return -1;
+ }
+ /* poll cq first */
+ while (wr_id != wrid_requested) {
+ ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
+ if (ret < 0) {
+ return ret;
+ }
+
+ wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
+
+ if (wr_id == RDMA_WRID_NONE) {
+ break;
+ }
+ if (wr_id != wrid_requested) {
+ DDDPRINTF("A Wanted wrid %s (%d) but got %s (%" PRIu64 ")\n",
+ print_wrid(wrid_requested),
+ wrid_requested, print_wrid(wr_id), wr_id);
+ }
+ }
+
+ if (wr_id == wrid_requested) {
+ return 0;
+ }
+
+ while (1) {
+ /*
+ * Coroutine doesn't start until process_incoming_migration()
+ * so don't yield unless we know we're running inside of a coroutine.
+ */
+ if (rdma->migration_started_on_destination) {
+ yield_until_fd_readable(rdma->comp_channel->fd);
+ }
+
+ if (ibv_get_cq_event(rdma->comp_channel, &cq, &cq_ctx)) {
+ perror("ibv_get_cq_event");
+ goto err_block_for_wrid;
+ }
+
+ num_cq_events++;
+
+ if (ibv_req_notify_cq(cq, 0)) {
+ goto err_block_for_wrid;
+ }
+
+ while (wr_id != wrid_requested) {
+ ret = qemu_rdma_poll(rdma, &wr_id_in, byte_len);
+ if (ret < 0) {
+ goto err_block_for_wrid;
+ }
+
+ wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
+
+ if (wr_id == RDMA_WRID_NONE) {
+ break;
+ }
+ if (wr_id != wrid_requested) {
+ DDDPRINTF("B Wanted wrid %s (%d) but got %s (%" PRIu64 ")\n",
+ print_wrid(wrid_requested), wrid_requested,
+ print_wrid(wr_id), wr_id);
+ }
+ }
+
+ if (wr_id == wrid_requested) {
+ goto success_block_for_wrid;
+ }
+ }
+
+success_block_for_wrid:
+ if (num_cq_events) {
+ ibv_ack_cq_events(cq, num_cq_events);
+ }
+ return 0;
+
+err_block_for_wrid:
+ if (num_cq_events) {
+ ibv_ack_cq_events(cq, num_cq_events);
+ }
+ return ret;
+}
+
+/*
+ * Post a SEND message work request for the control channel
+ * containing some data and block until the post completes.
+ */
+static int qemu_rdma_post_send_control(RDMAContext *rdma, uint8_t *buf,
+ RDMAControlHeader *head)
+{
+ int ret = 0;
+ RDMAWorkRequestData *wr = &rdma->wr_data[RDMA_WRID_CONTROL];
+ struct ibv_send_wr *bad_wr;
+ struct ibv_sge sge = {
+ .addr = (uint64_t)(wr->control),
+ .length = head->len + sizeof(RDMAControlHeader),
+ .lkey = wr->control_mr->lkey,
+ };
+ struct ibv_send_wr send_wr = {
+ .wr_id = RDMA_WRID_SEND_CONTROL,
+ .opcode = IBV_WR_SEND,
+ .send_flags = IBV_SEND_SIGNALED,
+ .sg_list = &sge,
+ .num_sge = 1,
+ };
+
+ DDDPRINTF("CONTROL: sending %s..\n", control_desc[head->type]);
+
+ /*
+ * We don't actually need to do a memcpy() in here if we used
+ * the "sge" properly, but since we're only sending control messages
+ * (not RAM in a performance-critical path), then its OK for now.
+ *
+ * The copy makes the RDMAControlHeader simpler to manipulate
+ * for the time being.
+ */
+ assert(head->len <= RDMA_CONTROL_MAX_BUFFER - sizeof(*head));
+ memcpy(wr->control, head, sizeof(RDMAControlHeader));
+ control_to_network((void *) wr->control);
+
+ if (buf) {
+ memcpy(wr->control + sizeof(RDMAControlHeader), buf, head->len);
+ }
+
+
+ ret = ibv_post_send(rdma->qp, &send_wr, &bad_wr);
+
+ if (ret > 0) {
+ fprintf(stderr, "Failed to use post IB SEND for control!\n");
+ return -ret;
+ }
+
+ ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_SEND_CONTROL, NULL);
+ if (ret < 0) {
+ fprintf(stderr, "rdma migration: send polling control error!\n");
+ }
+
+ return ret;
+}
+
+/*
+ * Post a RECV work request in anticipation of some future receipt
+ * of data on the control channel.
+ */
+static int qemu_rdma_post_recv_control(RDMAContext *rdma, int idx)
+{
+ struct ibv_recv_wr *bad_wr;
+ struct ibv_sge sge = {
+ .addr = (uint64_t)(rdma->wr_data[idx].control),
+ .length = RDMA_CONTROL_MAX_BUFFER,
+ .lkey = rdma->wr_data[idx].control_mr->lkey,
+ };
+
+ struct ibv_recv_wr recv_wr = {
+ .wr_id = RDMA_WRID_RECV_CONTROL + idx,
+ .sg_list = &sge,
+ .num_sge = 1,
+ };
+
+
+ if (ibv_post_recv(rdma->qp, &recv_wr, &bad_wr)) {
+ return -1;
+ }
+
+ return 0;
+}
+
+/*
+ * Block and wait for a RECV control channel message to arrive.
+ */
+static int qemu_rdma_exchange_get_response(RDMAContext *rdma,
+ RDMAControlHeader *head, int expecting, int idx)
+{
+ uint32_t byte_len;
+ int ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RECV_CONTROL + idx,
+ &byte_len);
+
+ if (ret < 0) {
+ fprintf(stderr, "rdma migration: recv polling control error!\n");
+ return ret;
+ }
+
+ network_to_control((void *) rdma->wr_data[idx].control);
+ memcpy(head, rdma->wr_data[idx].control, sizeof(RDMAControlHeader));
+
+ DDDPRINTF("CONTROL: %s receiving...\n", control_desc[expecting]);
+
+ if (expecting == RDMA_CONTROL_NONE) {
+ DDDPRINTF("Surprise: got %s (%d)\n",
+ control_desc[head->type], head->type);
+ } else if (head->type != expecting || head->type == RDMA_CONTROL_ERROR) {
+ fprintf(stderr, "Was expecting a %s (%d) control message"
+ ", but got: %s (%d), length: %d\n",
+ control_desc[expecting], expecting,
+ control_desc[head->type], head->type, head->len);
+ return -EIO;
+ }
+ if (head->len > RDMA_CONTROL_MAX_BUFFER - sizeof(*head)) {
+ fprintf(stderr, "too long length: %d\n", head->len);
+ return -EINVAL;
+ }
+ if (sizeof(*head) + head->len != byte_len) {
+ fprintf(stderr, "Malformed length: %d byte_len %d\n",
+ head->len, byte_len);
+ return -EINVAL;
+ }
+
+ return 0;
+}
+
+/*
+ * When a RECV work request has completed, the work request's
+ * buffer is pointed at the header.
+ *
+ * This will advance the pointer to the data portion
+ * of the control message of the work request's buffer that
+ * was populated after the work request finished.
+ */
+static void qemu_rdma_move_header(RDMAContext *rdma, int idx,
+ RDMAControlHeader *head)
+{
+ rdma->wr_data[idx].control_len = head->len;
+ rdma->wr_data[idx].control_curr =
+ rdma->wr_data[idx].control + sizeof(RDMAControlHeader);
+}
+
+/*
+ * This is an 'atomic' high-level operation to deliver a single, unified
+ * control-channel message.
+ *
+ * Additionally, if the user is expecting some kind of reply to this message,
+ * they can request a 'resp' response message be filled in by posting an
+ * additional work request on behalf of the user and waiting for an additional
+ * completion.
+ *
+ * The extra (optional) response is used during registration to us from having
+ * to perform an *additional* exchange of message just to provide a response by
+ * instead piggy-backing on the acknowledgement.
+ */
+static int qemu_rdma_exchange_send(RDMAContext *rdma, RDMAControlHeader *head,
+ uint8_t *data, RDMAControlHeader *resp,
+ int *resp_idx,
+ int (*callback)(RDMAContext *rdma))
+{
+ int ret = 0;
+
+ /*
+ * Wait until the dest is ready before attempting to deliver the message
+ * by waiting for a READY message.
+ */
+ if (rdma->control_ready_expected) {
+ RDMAControlHeader resp;
+ ret = qemu_rdma_exchange_get_response(rdma,
+ &resp, RDMA_CONTROL_READY, RDMA_WRID_READY);
+ if (ret < 0) {
+ return ret;
+ }
+ }
+
+ /*
+ * If the user is expecting a response, post a WR in anticipation of it.
+ */
+ if (resp) {
+ ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_DATA);
+ if (ret) {
+ fprintf(stderr, "rdma migration: error posting"
+ " extra control recv for anticipated result!");
+ return ret;
+ }
+ }
+
+ /*
+ * Post a WR to replace the one we just consumed for the READY message.
+ */
+ ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
+ if (ret) {
+ fprintf(stderr, "rdma migration: error posting first control recv!");
+ return ret;
+ }
+
+ /*
+ * Deliver the control message that was requested.
+ */
+ ret = qemu_rdma_post_send_control(rdma, data, head);
+
+ if (ret < 0) {
+ fprintf(stderr, "Failed to send control buffer!\n");
+ return ret;
+ }
+
+ /*
+ * If we're expecting a response, block and wait for it.
+ */
+ if (resp) {
+ if (callback) {
+ DDPRINTF("Issuing callback before receiving response...\n");
+ ret = callback(rdma);
+ if (ret < 0) {
+ return ret;
+ }
+ }
+
+ DDPRINTF("Waiting for response %s\n", control_desc[resp->type]);
+ ret = qemu_rdma_exchange_get_response(rdma, resp,
+ resp->type, RDMA_WRID_DATA);
+
+ if (ret < 0) {
+ return ret;
+ }
+
+ qemu_rdma_move_header(rdma, RDMA_WRID_DATA, resp);
+ if (resp_idx) {
+ *resp_idx = RDMA_WRID_DATA;
+ }
+ DDPRINTF("Response %s received.\n", control_desc[resp->type]);
+ }
+
+ rdma->control_ready_expected = 1;
+
+ return 0;
+}
+
+/*
+ * This is an 'atomic' high-level operation to receive a single, unified
+ * control-channel message.
+ */
+static int qemu_rdma_exchange_recv(RDMAContext *rdma, RDMAControlHeader *head,
+ int expecting)
+{
+ RDMAControlHeader ready = {
+ .len = 0,
+ .type = RDMA_CONTROL_READY,
+ .repeat = 1,
+ };
+ int ret;
+
+ /*
+ * Inform the source that we're ready to receive a message.
+ */
+ ret = qemu_rdma_post_send_control(rdma, NULL, &ready);
+
+ if (ret < 0) {
+ fprintf(stderr, "Failed to send control buffer!\n");
+ return ret;
+ }
+
+ /*
+ * Block and wait for the message.
+ */
+ ret = qemu_rdma_exchange_get_response(rdma, head,
+ expecting, RDMA_WRID_READY);
+
+ if (ret < 0) {
+ return ret;
+ }
+
+ qemu_rdma_move_header(rdma, RDMA_WRID_READY, head);
+
+ /*
+ * Post a new RECV work request to replace the one we just consumed.
+ */
+ ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
+ if (ret) {
+ fprintf(stderr, "rdma migration: error posting second control recv!");
+ return ret;
+ }
+
+ return 0;
+}
+
+/*
+ * Write an actual chunk of memory using RDMA.
+ *
+ * If we're using dynamic registration on the dest-side, we have to
+ * send a registration command first.
+ */
+static int qemu_rdma_write_one(QEMUFile *f, RDMAContext *rdma,
+ int current_index, uint64_t current_addr,
+ uint64_t length)
+{
+ struct ibv_sge sge;
+ struct ibv_send_wr send_wr = { 0 };
+ struct ibv_send_wr *bad_wr;
+ int reg_result_idx, ret, count = 0;
+ uint64_t chunk, chunks;
+ uint8_t *chunk_start, *chunk_end;
+ RDMALocalBlock *block = &(rdma->local_ram_blocks.block[current_index]);
+ RDMARegister reg;
+ RDMARegisterResult *reg_result;
+ RDMAControlHeader resp = { .type = RDMA_CONTROL_REGISTER_RESULT };
+ RDMAControlHeader head = { .len = sizeof(RDMARegister),
+ .type = RDMA_CONTROL_REGISTER_REQUEST,
+ .repeat = 1,
+ };
+
+retry:
+ sge.addr = (uint64_t)(block->local_host_addr +
+ (current_addr - block->offset));
+ sge.length = length;
+
+ chunk = ram_chunk_index(block->local_host_addr, (uint8_t *) sge.addr);
+ chunk_start = ram_chunk_start(block, chunk);
+
+ if (block->is_ram_block) {
+ chunks = length / (1UL << RDMA_REG_CHUNK_SHIFT);
+
+ if (chunks && ((length % (1UL << RDMA_REG_CHUNK_SHIFT)) == 0)) {
+ chunks--;
+ }
+ } else {
+ chunks = block->length / (1UL << RDMA_REG_CHUNK_SHIFT);
+
+ if (chunks && ((block->length % (1UL << RDMA_REG_CHUNK_SHIFT)) == 0)) {
+ chunks--;
+ }
+ }
+
+ DDPRINTF("Writing %" PRIu64 " chunks, (%" PRIu64 " MB)\n",
+ chunks + 1, (chunks + 1) * (1UL << RDMA_REG_CHUNK_SHIFT) / 1024 / 1024);
+
+ chunk_end = ram_chunk_end(block, chunk + chunks);
+
+ if (!rdma->pin_all) {
+#ifdef RDMA_UNREGISTRATION_EXAMPLE
+ qemu_rdma_unregister_waiting(rdma);
+#endif
+ }
+
+ while (test_bit(chunk, block->transit_bitmap)) {
+ (void)count;
+ DDPRINTF("(%d) Not clobbering: block: %d chunk %" PRIu64
+ " current %" PRIu64 " len %" PRIu64 " %d %d\n",
+ count++, current_index, chunk,
+ sge.addr, length, rdma->nb_sent, block->nb_chunks);
+
+ ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
+
+ if (ret < 0) {
+ fprintf(stderr, "Failed to Wait for previous write to complete "
+ "block %d chunk %" PRIu64
+ " current %" PRIu64 " len %" PRIu64 " %d\n",
+ current_index, chunk, sge.addr, length, rdma->nb_sent);
+ return ret;
+ }
+ }
+
+ if (!rdma->pin_all || !block->is_ram_block) {
+ if (!block->remote_keys[chunk]) {
+ /*
+ * This chunk has not yet been registered, so first check to see
+ * if the entire chunk is zero. If so, tell the other size to
+ * memset() + madvise() the entire chunk without RDMA.
+ */
+
+ if (can_use_buffer_find_nonzero_offset((void *)sge.addr, length)
+ && buffer_find_nonzero_offset((void *)sge.addr,
+ length) == length) {
+ RDMACompress comp = {
+ .offset = current_addr,
+ .value = 0,
+ .block_idx = current_index,
+ .length = length,
+ };
+
+ head.len = sizeof(comp);
+ head.type = RDMA_CONTROL_COMPRESS;
+
+ DDPRINTF("Entire chunk is zero, sending compress: %"
+ PRIu64 " for %d "
+ "bytes, index: %d, offset: %" PRId64 "...\n",
+ chunk, sge.length, current_index, current_addr);
+
+ compress_to_network(&comp);
+ ret = qemu_rdma_exchange_send(rdma, &head,
+ (uint8_t *) &comp, NULL, NULL, NULL);
+
+ if (ret < 0) {
+ return -EIO;
+ }
+
+ acct_update_position(f, sge.length, true);
+
+ return 1;
+ }
+
+ /*
+ * Otherwise, tell other side to register.
+ */
+ reg.current_index = current_index;
+ if (block->is_ram_block) {
+ reg.key.current_addr = current_addr;
+ } else {
+ reg.key.chunk = chunk;
+ }
+ reg.chunks = chunks;
+
+ DDPRINTF("Sending registration request chunk %" PRIu64 " for %d "
+ "bytes, index: %d, offset: %" PRId64 "...\n",
+ chunk, sge.length, current_index, current_addr);
+
+ register_to_network(®);
+ ret = qemu_rdma_exchange_send(rdma, &head, (uint8_t *) ®,
+ &resp, ®_result_idx, NULL);
+ if (ret < 0) {
+ return ret;
+ }
+
+ /* try to overlap this single registration with the one we sent. */
+ if (qemu_rdma_register_and_get_keys(rdma, block,
+ (uint8_t *) sge.addr,
+ &sge.lkey, NULL, chunk,
+ chunk_start, chunk_end)) {
+ fprintf(stderr, "cannot get lkey!\n");
+ return -EINVAL;
+ }
+
+ reg_result = (RDMARegisterResult *)
+ rdma->wr_data[reg_result_idx].control_curr;
+
+ network_to_result(reg_result);
+
+ DDPRINTF("Received registration result:"
+ " my key: %x their key %x, chunk %" PRIu64 "\n",
+ block->remote_keys[chunk], reg_result->rkey, chunk);
+
+ block->remote_keys[chunk] = reg_result->rkey;
+ block->remote_host_addr = reg_result->host_addr;
+ } else {
+ /* already registered before */
+ if (qemu_rdma_register_and_get_keys(rdma, block,
+ (uint8_t *)sge.addr,
+ &sge.lkey, NULL, chunk,
+ chunk_start, chunk_end)) {
+ fprintf(stderr, "cannot get lkey!\n");
+ return -EINVAL;
+ }
+ }
+
+ send_wr.wr.rdma.rkey = block->remote_keys[chunk];
+ } else {
+ send_wr.wr.rdma.rkey = block->remote_rkey;
+
+ if (qemu_rdma_register_and_get_keys(rdma, block, (uint8_t *)sge.addr,
+ &sge.lkey, NULL, chunk,
+ chunk_start, chunk_end)) {
+ fprintf(stderr, "cannot get lkey!\n");
+ return -EINVAL;
+ }
+ }
+
+ /*
+ * Encode the ram block index and chunk within this wrid.
+ * We will use this information at the time of completion
+ * to figure out which bitmap to check against and then which
+ * chunk in the bitmap to look for.
+ */
+ send_wr.wr_id = qemu_rdma_make_wrid(RDMA_WRID_RDMA_WRITE,
+ current_index, chunk);
+
+ send_wr.opcode = IBV_WR_RDMA_WRITE;
+ send_wr.send_flags = IBV_SEND_SIGNALED;
+ send_wr.sg_list = &sge;
+ send_wr.num_sge = 1;
+ send_wr.wr.rdma.remote_addr = block->remote_host_addr +
+ (current_addr - block->offset);
+
+ DDDPRINTF("Posting chunk: %" PRIu64 ", addr: %lx"
+ " remote: %lx, bytes %" PRIu32 "\n",
+ chunk, sge.addr, send_wr.wr.rdma.remote_addr,
+ sge.length);
+
+ /*
+ * ibv_post_send() does not return negative error numbers,
+ * per the specification they are positive - no idea why.
+ */
+ ret = ibv_post_send(rdma->qp, &send_wr, &bad_wr);
+
+ if (ret == ENOMEM) {
+ DDPRINTF("send queue is full. wait a little....\n");
+ ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
+ if (ret < 0) {
+ fprintf(stderr, "rdma migration: failed to make "
+ "room in full send queue! %d\n", ret);
+ return ret;
+ }
+
+ goto retry;
+
+ } else if (ret > 0) {
+ perror("rdma migration: post rdma write failed");
+ return -ret;
+ }
+
+ set_bit(chunk, block->transit_bitmap);
+ acct_update_position(f, sge.length, false);
+ rdma->total_writes++;
+
+ return 0;
+}
+
+/*
+ * Push out any unwritten RDMA operations.
+ *
+ * We support sending out multiple chunks at the same time.
+ * Not all of them need to get signaled in the completion queue.
+ */
+static int qemu_rdma_write_flush(QEMUFile *f, RDMAContext *rdma)
+{
+ int ret;
+
+ if (!rdma->current_length) {
+ return 0;
+ }
+
+ ret = qemu_rdma_write_one(f, rdma,
+ rdma->current_index, rdma->current_addr, rdma->current_length);
+
+ if (ret < 0) {
+ return ret;
+ }
+
+ if (ret == 0) {
+ rdma->nb_sent++;
+ DDDPRINTF("sent total: %d\n", rdma->nb_sent);
+ }
+
+ rdma->current_length = 0;
+ rdma->current_addr = 0;
+
+ return 0;
+}
+
+static inline int qemu_rdma_buffer_mergable(RDMAContext *rdma,
+ uint64_t offset, uint64_t len)
+{
+ RDMALocalBlock *block;
+ uint8_t *host_addr;
+ uint8_t *chunk_end;
+
+ if (rdma->current_index < 0) {
+ return 0;
+ }
+
+ if (rdma->current_chunk < 0) {
+ return 0;
+ }
+
+ block = &(rdma->local_ram_blocks.block[rdma->current_index]);
+ host_addr = block->local_host_addr + (offset - block->offset);
+ chunk_end = ram_chunk_end(block, rdma->current_chunk);
+
+ if (rdma->current_length == 0) {
+ return 0;
+ }
+
+ /*
+ * Only merge into chunk sequentially.
+ */
+ if (offset != (rdma->current_addr + rdma->current_length)) {
+ return 0;
+ }
+
+ if (offset < block->offset) {
+ return 0;
+ }
+
+ if ((offset + len) > (block->offset + block->length)) {
+ return 0;
+ }
+
+ if ((host_addr + len) > chunk_end) {
+ return 0;
+ }
+
+ return 1;
+}
+
+/*
+ * We're not actually writing here, but doing three things:
+ *
+ * 1. Identify the chunk the buffer belongs to.
+ * 2. If the chunk is full or the buffer doesn't belong to the current
+ * chunk, then start a new chunk and flush() the old chunk.
+ * 3. To keep the hardware busy, we also group chunks into batches
+ * and only require that a batch gets acknowledged in the completion
+ * qeueue instead of each individual chunk.
+ */
+static int qemu_rdma_write(QEMUFile *f, RDMAContext *rdma,
+ uint64_t block_offset, uint64_t offset,
+ uint64_t len)
+{
+ uint64_t current_addr = block_offset + offset;
+ uint64_t index = rdma->current_index;
+ uint64_t chunk = rdma->current_chunk;
+ int ret;
+
+ /* If we cannot merge it, we flush the current buffer first. */
+ if (!qemu_rdma_buffer_mergable(rdma, current_addr, len)) {
+ ret = qemu_rdma_write_flush(f, rdma);
+ if (ret) {
+ return ret;
+ }
+ rdma->current_length = 0;
+ rdma->current_addr = current_addr;
+
+ ret = qemu_rdma_search_ram_block(rdma, block_offset,
+ offset, len, &index, &chunk);
+ if (ret) {
+ fprintf(stderr, "ram block search failed\n");
+ return ret;
+ }
+ rdma->current_index = index;
+ rdma->current_chunk = chunk;
+ }
+
+ /* merge it */
+ rdma->current_length += len;
+
+ /* flush it if buffer is too large */
+ if (rdma->current_length >= RDMA_MERGE_MAX) {
+ return qemu_rdma_write_flush(f, rdma);
+ }
+
+ return 0;
+}
+
+static void qemu_rdma_cleanup(RDMAContext *rdma)
+{
+ struct rdma_cm_event *cm_event;
+ int ret, idx;
+
+ if (rdma->cm_id && rdma->connected) {
+ if (rdma->error_state) {
+ RDMAControlHeader head = { .len = 0,
+ .type = RDMA_CONTROL_ERROR,
+ .repeat = 1,
+ };
+ fprintf(stderr, "Early error. Sending error.\n");
+ qemu_rdma_post_send_control(rdma, NULL, &head);
+ }
+
+ ret = rdma_disconnect(rdma->cm_id);
+ if (!ret) {
+ DDPRINTF("waiting for disconnect\n");
+ ret = rdma_get_cm_event(rdma->channel, &cm_event);
+ if (!ret) {
+ rdma_ack_cm_event(cm_event);
+ }
+ }
+ DDPRINTF("Disconnected.\n");
+ rdma->connected = false;
+ }
+
+ g_free(rdma->block);
+ rdma->block = NULL;
+
+ for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
+ if (rdma->wr_data[idx].control_mr) {
+ rdma->total_registrations--;
+ ibv_dereg_mr(rdma->wr_data[idx].control_mr);
+ }
+ rdma->wr_data[idx].control_mr = NULL;
+ }
+
+ if (rdma->local_ram_blocks.block) {
+ while (rdma->local_ram_blocks.nb_blocks) {
+ __qemu_rdma_delete_block(rdma,
+ rdma->local_ram_blocks.block->offset);
+ }
+ }
+
+ if (rdma->cq) {
+ ibv_destroy_cq(rdma->cq);
+ rdma->cq = NULL;
+ }
+ if (rdma->comp_channel) {
+ ibv_destroy_comp_channel(rdma->comp_channel);
+ rdma->comp_channel = NULL;
+ }
+ if (rdma->pd) {
+ ibv_dealloc_pd(rdma->pd);
+ rdma->pd = NULL;
+ }
+ if (rdma->listen_id) {
+ rdma_destroy_id(rdma->listen_id);
+ rdma->listen_id = NULL;
+ }
+ if (rdma->cm_id) {
+ if (rdma->qp) {
+ rdma_destroy_qp(rdma->cm_id);
+ rdma->qp = NULL;
+ }
+ rdma_destroy_id(rdma->cm_id);
+ rdma->cm_id = NULL;
+ }
+ if (rdma->channel) {
+ rdma_destroy_event_channel(rdma->channel);
+ rdma->channel = NULL;
+ }
+ g_free(rdma->host);
+ rdma->host = NULL;
+}
+
+
+static int qemu_rdma_source_init(RDMAContext *rdma, Error **errp, bool pin_all)
+{
+ int ret, idx;
+ Error *local_err = NULL, **temp = &local_err;
+
+ /*
+ * Will be validated against destination's actual capabilities
+ * after the connect() completes.
+ */
+ rdma->pin_all = pin_all;
+
+ ret = qemu_rdma_resolve_host(rdma, temp);
+ if (ret) {
+ goto err_rdma_source_init;
+ }
+
+ ret = qemu_rdma_alloc_pd_cq(rdma);
+ if (ret) {
+ ERROR(temp, "rdma migration: error allocating pd and cq! Your mlock()"
+ " limits may be too low. Please check $ ulimit -a # and "
+ "search for 'ulimit -l' in the output");
+ goto err_rdma_source_init;
+ }
+
+ ret = qemu_rdma_alloc_qp(rdma);
+ if (ret) {
+ ERROR(temp, "rdma migration: error allocating qp!");
+ goto err_rdma_source_init;
+ }
+
+ ret = qemu_rdma_init_ram_blocks(rdma);
+ if (ret) {
+ ERROR(temp, "rdma migration: error initializing ram blocks!");
+ goto err_rdma_source_init;
+ }
+
+ for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
+ ret = qemu_rdma_reg_control(rdma, idx);
+ if (ret) {
+ ERROR(temp, "rdma migration: error registering %d control!",
+ idx);
+ goto err_rdma_source_init;
+ }
+ }
+
+ return 0;
+
+err_rdma_source_init:
+ error_propagate(errp, local_err);
+ qemu_rdma_cleanup(rdma);
+ return -1;
+}
+
+static int qemu_rdma_connect(RDMAContext *rdma, Error **errp)
+{
+ RDMACapabilities cap = {
+ .version = RDMA_CONTROL_VERSION_CURRENT,
+ .flags = 0,
+ };
+ struct rdma_conn_param conn_param = { .initiator_depth = 2,
+ .retry_count = 5,
+ .private_data = &cap,
+ .private_data_len = sizeof(cap),
+ };
+ struct rdma_cm_event *cm_event;
+ int ret;
+
+ /*
+ * Only negotiate the capability with destination if the user
+ * on the source first requested the capability.
+ */
+ if (rdma->pin_all) {
+ DPRINTF("Server pin-all memory requested.\n");
+ cap.flags |= RDMA_CAPABILITY_PIN_ALL;
+ }
+
+ caps_to_network(&cap);
+
+ ret = rdma_connect(rdma->cm_id, &conn_param);
+ if (ret) {
+ perror("rdma_connect");
+ ERROR(errp, "connecting to destination!");
+ rdma_destroy_id(rdma->cm_id);
+ rdma->cm_id = NULL;
+ goto err_rdma_source_connect;
+ }
+
+ ret = rdma_get_cm_event(rdma->channel, &cm_event);
+ if (ret) {
+ perror("rdma_get_cm_event after rdma_connect");
+ ERROR(errp, "connecting to destination!");
+ rdma_ack_cm_event(cm_event);
+ rdma_destroy_id(rdma->cm_id);
+ rdma->cm_id = NULL;
+ goto err_rdma_source_connect;
+ }
+
+ if (cm_event->event != RDMA_CM_EVENT_ESTABLISHED) {
+ perror("rdma_get_cm_event != EVENT_ESTABLISHED after rdma_connect");
+ ERROR(errp, "connecting to destination!");
+ rdma_ack_cm_event(cm_event);
+ rdma_destroy_id(rdma->cm_id);
+ rdma->cm_id = NULL;
+ goto err_rdma_source_connect;
+ }
+ rdma->connected = true;
+
+ memcpy(&cap, cm_event->param.conn.private_data, sizeof(cap));
+ network_to_caps(&cap);
+
+ /*
+ * Verify that the *requested* capabilities are supported by the destination
+ * and disable them otherwise.
+ */
+ if (rdma->pin_all && !(cap.flags & RDMA_CAPABILITY_PIN_ALL)) {
+ ERROR(errp, "Server cannot support pinning all memory. "
+ "Will register memory dynamically.");
+ rdma->pin_all = false;
+ }
+
+ DPRINTF("Pin all memory: %s\n", rdma->pin_all ? "enabled" : "disabled");
+
+ rdma_ack_cm_event(cm_event);
+
+ ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
+ if (ret) {
+ ERROR(errp, "posting second control recv!");
+ goto err_rdma_source_connect;
+ }
+
+ rdma->control_ready_expected = 1;
+ rdma->nb_sent = 0;
+ return 0;
+
+err_rdma_source_connect:
+ qemu_rdma_cleanup(rdma);
+ return -1;
+}
+
+static int qemu_rdma_dest_init(RDMAContext *rdma, Error **errp)
+{
+ int ret = -EINVAL, idx;
+ struct rdma_cm_id *listen_id;
+ char ip[40] = "unknown";
+ struct rdma_addrinfo *res;
+ char port_str[16];
+
+ for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
+ rdma->wr_data[idx].control_len = 0;
+ rdma->wr_data[idx].control_curr = NULL;
+ }
+
+ if (rdma->host == NULL) {
+ ERROR(errp, "RDMA host is not set!");
+ rdma->error_state = -EINVAL;
+ return -1;
+ }
+ /* create CM channel */
+ rdma->channel = rdma_create_event_channel();
+ if (!rdma->channel) {
+ ERROR(errp, "could not create rdma event channel");
+ rdma->error_state = -EINVAL;
+ return -1;
+ }
+
+ /* create CM id */
+ ret = rdma_create_id(rdma->channel, &listen_id, NULL, RDMA_PS_TCP);
+ if (ret) {
+ ERROR(errp, "could not create cm_id!");
+ goto err_dest_init_create_listen_id;
+ }
+
+ snprintf(port_str, 16, "%d", rdma->port);
+ port_str[15] = '\0';
+
+ if (rdma->host && strcmp("", rdma->host)) {
+ struct rdma_addrinfo *e;
+
+ ret = rdma_getaddrinfo(rdma->host, port_str, NULL, &res);
+ if (ret < 0) {
+ ERROR(errp, "could not rdma_getaddrinfo address %s", rdma->host);
+ goto err_dest_init_bind_addr;
+ }
+
+ for (e = res; e != NULL; e = e->ai_next) {
+ inet_ntop(e->ai_family,
+ &((struct sockaddr_in *) e->ai_dst_addr)->sin_addr, ip, sizeof ip);
+ DPRINTF("Trying %s => %s\n", rdma->host, ip);
+ ret = rdma_bind_addr(listen_id, e->ai_dst_addr);
+ if (!ret) {
+ if (e->ai_family == AF_INET6) {
+ ret = qemu_rdma_broken_ipv6_kernel(errp, listen_id->verbs);
+ if (ret) {
+ continue;
+ }
+ }
+
+ goto listen;
+ }
+ }
+
+ ERROR(errp, "Error: could not rdma_bind_addr!");
+ goto err_dest_init_bind_addr;
+ } else {
+ ERROR(errp, "migration host and port not specified!");
+ ret = -EINVAL;
+ goto err_dest_init_bind_addr;
+ }
+listen:
+
+ rdma->listen_id = listen_id;
+ qemu_rdma_dump_gid("dest_init", listen_id);
+ return 0;
+
+err_dest_init_bind_addr:
+ rdma_destroy_id(listen_id);
+err_dest_init_create_listen_id:
+ rdma_destroy_event_channel(rdma->channel);
+ rdma->channel = NULL;
+ rdma->error_state = ret;
+ return ret;
+
+}
+
+static void *qemu_rdma_data_init(const char *host_port, Error **errp)
+{
+ RDMAContext *rdma = NULL;
+ InetSocketAddress *addr;
+
+ if (host_port) {
+ rdma = g_malloc0(sizeof(RDMAContext));
+ memset(rdma, 0, sizeof(RDMAContext));
+ rdma->current_index = -1;
+ rdma->current_chunk = -1;
+
+ addr = inet_parse(host_port, NULL);
+ if (addr != NULL) {
+ rdma->port = atoi(addr->port);
+ rdma->host = g_strdup(addr->host);
+ } else {
+ ERROR(errp, "bad RDMA migration address '%s'", host_port);
+ g_free(rdma);
+ rdma = NULL;
+ }
+
+ qapi_free_InetSocketAddress(addr);
+ }
+
+ return rdma;
+}
+
+/*
+ * QEMUFile interface to the control channel.
+ * SEND messages for control only.
+ * VM's ram is handled with regular RDMA messages.
+ */
+static int qemu_rdma_put_buffer(void *opaque, const uint8_t *buf,
+ int64_t pos, int size)
+{
+ QEMUFileRDMA *r = opaque;
+ QEMUFile *f = r->file;
+ RDMAContext *rdma = r->rdma;
+ size_t remaining = size;
+ uint8_t * data = (void *) buf;
+ int ret;
+
+ CHECK_ERROR_STATE();
+
+ /*
+ * Push out any writes that
+ * we're queued up for VM's ram.
+ */
+ ret = qemu_rdma_write_flush(f, rdma);
+ if (ret < 0) {
+ rdma->error_state = ret;
+ return ret;
+ }
+
+ while (remaining) {
+ RDMAControlHeader head;
+
+ r->len = MIN(remaining, RDMA_SEND_INCREMENT);
+ remaining -= r->len;
+
+ head.len = r->len;
+ head.type = RDMA_CONTROL_QEMU_FILE;
+
+ ret = qemu_rdma_exchange_send(rdma, &head, data, NULL, NULL, NULL);
+
+ if (ret < 0) {
+ rdma->error_state = ret;
+ return ret;
+ }
+
+ data += r->len;
+ }
+
+ return size;
+}
+
+static size_t qemu_rdma_fill(RDMAContext *rdma, uint8_t *buf,
+ int size, int idx)
+{
+ size_t len = 0;
+
+ if (rdma->wr_data[idx].control_len) {
+ DDDPRINTF("RDMA %" PRId64 " of %d bytes already in buffer\n",
+ rdma->wr_data[idx].control_len, size);
+
+ len = MIN(size, rdma->wr_data[idx].control_len);
+ memcpy(buf, rdma->wr_data[idx].control_curr, len);
+ rdma->wr_data[idx].control_curr += len;
+ rdma->wr_data[idx].control_len -= len;
+ }
+
+ return len;
+}
+
+/*
+ * QEMUFile interface to the control channel.
+ * RDMA links don't use bytestreams, so we have to
+ * return bytes to QEMUFile opportunistically.
+ */
+static int qemu_rdma_get_buffer(void *opaque, uint8_t *buf,
+ int64_t pos, int size)
+{
+ QEMUFileRDMA *r = opaque;
+ RDMAContext *rdma = r->rdma;
+ RDMAControlHeader head;
+ int ret = 0;
+
+ CHECK_ERROR_STATE();
+
+ /*
+ * First, we hold on to the last SEND message we
+ * were given and dish out the bytes until we run
+ * out of bytes.
+ */
+ r->len = qemu_rdma_fill(r->rdma, buf, size, 0);
+ if (r->len) {
+ return r->len;
+ }
+
+ /*
+ * Once we run out, we block and wait for another
+ * SEND message to arrive.
+ */
+ ret = qemu_rdma_exchange_recv(rdma, &head, RDMA_CONTROL_QEMU_FILE);
+
+ if (ret < 0) {
+ rdma->error_state = ret;
+ return ret;
+ }
+
+ /*
+ * SEND was received with new bytes, now try again.
+ */
+ return qemu_rdma_fill(r->rdma, buf, size, 0);
+}
+
+/*
+ * Block until all the outstanding chunks have been delivered by the hardware.
+ */
+static int qemu_rdma_drain_cq(QEMUFile *f, RDMAContext *rdma)
+{
+ int ret;
+
+ if (qemu_rdma_write_flush(f, rdma) < 0) {
+ return -EIO;
+ }
+
+ while (rdma->nb_sent) {
+ ret = qemu_rdma_block_for_wrid(rdma, RDMA_WRID_RDMA_WRITE, NULL);
+ if (ret < 0) {
+ fprintf(stderr, "rdma migration: complete polling error!\n");
+ return -EIO;
+ }
+ }
+
+ qemu_rdma_unregister_waiting(rdma);
+
+ return 0;
+}
+
+static int qemu_rdma_close(void *opaque)
+{
+ DPRINTF("Shutting down connection.\n");
+ QEMUFileRDMA *r = opaque;
+ if (r->rdma) {
+ qemu_rdma_cleanup(r->rdma);
+ g_free(r->rdma);
+ }
+ g_free(r);
+ return 0;
+}
+
+/*
+ * Parameters:
+ * @offset == 0 :
+ * This means that 'block_offset' is a full virtual address that does not
+ * belong to a RAMBlock of the virtual machine and instead
+ * represents a private malloc'd memory area that the caller wishes to
+ * transfer.
+ *
+ * @offset != 0 :
+ * Offset is an offset to be added to block_offset and used
+ * to also lookup the corresponding RAMBlock.
+ *
+ * @size > 0 :
+ * Initiate an transfer this size.
+ *
+ * @size == 0 :
+ * A 'hint' or 'advice' that means that we wish to speculatively
+ * and asynchronously unregister this memory. In this case, there is no
+ * guarantee that the unregister will actually happen, for example,
+ * if the memory is being actively transmitted. Additionally, the memory
+ * may be re-registered at any future time if a write within the same
+ * chunk was requested again, even if you attempted to unregister it
+ * here.
+ *
+ * @size < 0 : TODO, not yet supported
+ * Unregister the memory NOW. This means that the caller does not
+ * expect there to be any future RDMA transfers and we just want to clean
+ * things up. This is used in case the upper layer owns the memory and
+ * cannot wait for qemu_fclose() to occur.
+ *
+ * @bytes_sent : User-specificed pointer to indicate how many bytes were
+ * sent. Usually, this will not be more than a few bytes of
+ * the protocol because most transfers are sent asynchronously.
+ */
+static size_t qemu_rdma_save_page(QEMUFile *f, void *opaque,
+ ram_addr_t block_offset, ram_addr_t offset,
+ size_t size, int *bytes_sent)
+{
+ QEMUFileRDMA *rfile = opaque;
+ RDMAContext *rdma = rfile->rdma;
+ int ret;
+
+ CHECK_ERROR_STATE();
+
+ qemu_fflush(f);
+
+ if (size > 0) {
+ /*
+ * Add this page to the current 'chunk'. If the chunk
+ * is full, or the page doen't belong to the current chunk,
+ * an actual RDMA write will occur and a new chunk will be formed.
+ */
+ ret = qemu_rdma_write(f, rdma, block_offset, offset, size);
+ if (ret < 0) {
+ fprintf(stderr, "rdma migration: write error! %d\n", ret);
+ goto err;
+ }
+
+ /*
+ * We always return 1 bytes because the RDMA
+ * protocol is completely asynchronous. We do not yet know
+ * whether an identified chunk is zero or not because we're
+ * waiting for other pages to potentially be merged with
+ * the current chunk. So, we have to call qemu_update_position()
+ * later on when the actual write occurs.
+ */
+ if (bytes_sent) {
+ *bytes_sent = 1;
+ }
+ } else {
+ uint64_t index, chunk;
+
+ /* TODO: Change QEMUFileOps prototype to be signed: size_t => long
+ if (size < 0) {
+ ret = qemu_rdma_drain_cq(f, rdma);
+ if (ret < 0) {
+ fprintf(stderr, "rdma: failed to synchronously drain"
+ " completion queue before unregistration.\n");
+ goto err;
+ }
+ }
+ */
+
+ ret = qemu_rdma_search_ram_block(rdma, block_offset,
+ offset, size, &index, &chunk);
+
+ if (ret) {
+ fprintf(stderr, "ram block search failed\n");
+ goto err;
+ }
+
+ qemu_rdma_signal_unregister(rdma, index, chunk, 0);
+
+ /*
+ * TODO: Synchronous, guaranteed unregistration (should not occur during
+ * fast-path). Otherwise, unregisters will process on the next call to
+ * qemu_rdma_drain_cq()
+ if (size < 0) {
+ qemu_rdma_unregister_waiting(rdma);
+ }
+ */
+ }
+
+ /*
+ * Drain the Completion Queue if possible, but do not block,
+ * just poll.
+ *
+ * If nothing to poll, the end of the iteration will do this
+ * again to make sure we don't overflow the request queue.
+ */
+ while (1) {
+ uint64_t wr_id, wr_id_in;
+ int ret = qemu_rdma_poll(rdma, &wr_id_in, NULL);
+ if (ret < 0) {
+ fprintf(stderr, "rdma migration: polling error! %d\n", ret);
+ goto err;
+ }
+
+ wr_id = wr_id_in & RDMA_WRID_TYPE_MASK;
+
+ if (wr_id == RDMA_WRID_NONE) {
+ break;
+ }
+ }
+
+ return RAM_SAVE_CONTROL_DELAYED;
+err:
+ rdma->error_state = ret;
+ return ret;
+}
+
+static int qemu_rdma_accept(RDMAContext *rdma)
+{
+ RDMACapabilities cap;
+ struct rdma_conn_param conn_param = {
+ .responder_resources = 2,
+ .private_data = &cap,
+ .private_data_len = sizeof(cap),
+ };
+ struct rdma_cm_event *cm_event;
+ struct ibv_context *verbs;
+ int ret = -EINVAL;
+ int idx;
+
+ ret = rdma_get_cm_event(rdma->channel, &cm_event);
+ if (ret) {
+ goto err_rdma_dest_wait;
+ }
+
+ if (cm_event->event != RDMA_CM_EVENT_CONNECT_REQUEST) {
+ rdma_ack_cm_event(cm_event);
+ goto err_rdma_dest_wait;
+ }
+
+ memcpy(&cap, cm_event->param.conn.private_data, sizeof(cap));
+
+ network_to_caps(&cap);
+
+ if (cap.version < 1 || cap.version > RDMA_CONTROL_VERSION_CURRENT) {
+ fprintf(stderr, "Unknown source RDMA version: %d, bailing...\n",
+ cap.version);
+ rdma_ack_cm_event(cm_event);
+ goto err_rdma_dest_wait;
+ }
+
+ /*
+ * Respond with only the capabilities this version of QEMU knows about.
+ */
+ cap.flags &= known_capabilities;
+
+ /*
+ * Enable the ones that we do know about.
+ * Add other checks here as new ones are introduced.
+ */
+ if (cap.flags & RDMA_CAPABILITY_PIN_ALL) {
+ rdma->pin_all = true;
+ }
+
+ rdma->cm_id = cm_event->id;
+ verbs = cm_event->id->verbs;
+
+ rdma_ack_cm_event(cm_event);
+
+ DPRINTF("Memory pin all: %s\n", rdma->pin_all ? "enabled" : "disabled");
+
+ caps_to_network(&cap);
+
+ DPRINTF("verbs context after listen: %p\n", verbs);
+
+ if (!rdma->verbs) {
+ rdma->verbs = verbs;
+ } else if (rdma->verbs != verbs) {
+ fprintf(stderr, "ibv context not matching %p, %p!\n",
+ rdma->verbs, verbs);
+ goto err_rdma_dest_wait;
+ }
+
+ qemu_rdma_dump_id("dest_init", verbs);
+
+ ret = qemu_rdma_alloc_pd_cq(rdma);
+ if (ret) {
+ fprintf(stderr, "rdma migration: error allocating pd and cq!\n");
+ goto err_rdma_dest_wait;
+ }
+
+ ret = qemu_rdma_alloc_qp(rdma);
+ if (ret) {
+ fprintf(stderr, "rdma migration: error allocating qp!\n");
+ goto err_rdma_dest_wait;
+ }
+
+ ret = qemu_rdma_init_ram_blocks(rdma);
+ if (ret) {
+ fprintf(stderr, "rdma migration: error initializing ram blocks!\n");
+ goto err_rdma_dest_wait;
+ }
+
+ for (idx = 0; idx < RDMA_WRID_MAX; idx++) {
+ ret = qemu_rdma_reg_control(rdma, idx);
+ if (ret) {
+ fprintf(stderr, "rdma: error registering %d control!\n", idx);
+ goto err_rdma_dest_wait;
+ }
+ }
+
+ qemu_set_fd_handler2(rdma->channel->fd, NULL, NULL, NULL, NULL);
+
+ ret = rdma_accept(rdma->cm_id, &conn_param);
+ if (ret) {
+ fprintf(stderr, "rdma_accept returns %d!\n", ret);
+ goto err_rdma_dest_wait;
+ }
+
+ ret = rdma_get_cm_event(rdma->channel, &cm_event);
+ if (ret) {
+ fprintf(stderr, "rdma_accept get_cm_event failed %d!\n", ret);
+ goto err_rdma_dest_wait;
+ }
+
+ if (cm_event->event != RDMA_CM_EVENT_ESTABLISHED) {
+ fprintf(stderr, "rdma_accept not event established!\n");
+ rdma_ack_cm_event(cm_event);
+ goto err_rdma_dest_wait;
+ }
+
+ rdma_ack_cm_event(cm_event);
+ rdma->connected = true;
+
+ ret = qemu_rdma_post_recv_control(rdma, RDMA_WRID_READY);
+ if (ret) {
+ fprintf(stderr, "rdma migration: error posting second control recv!\n");
+ goto err_rdma_dest_wait;
+ }
+
+ qemu_rdma_dump_gid("dest_connect", rdma->cm_id);
+
+ return 0;
+
+err_rdma_dest_wait:
+ rdma->error_state = ret;
+ qemu_rdma_cleanup(rdma);
+ return ret;
+}
+
+/*
+ * During each iteration of the migration, we listen for instructions
+ * by the source VM to perform dynamic page registrations before they
+ * can perform RDMA operations.
+ *
+ * We respond with the 'rkey'.
+ *
+ * Keep doing this until the source tells us to stop.
+ */
+static int qemu_rdma_registration_handle(QEMUFile *f, void *opaque,
+ uint64_t flags)
+{
+ RDMAControlHeader reg_resp = { .len = sizeof(RDMARegisterResult),
+ .type = RDMA_CONTROL_REGISTER_RESULT,
+ .repeat = 0,
+ };
+ RDMAControlHeader unreg_resp = { .len = 0,
+ .type = RDMA_CONTROL_UNREGISTER_FINISHED,
+ .repeat = 0,
+ };
+ RDMAControlHeader blocks = { .type = RDMA_CONTROL_RAM_BLOCKS_RESULT,
+ .repeat = 1 };
+ QEMUFileRDMA *rfile = opaque;
+ RDMAContext *rdma = rfile->rdma;
+ RDMALocalBlocks *local = &rdma->local_ram_blocks;
+ RDMAControlHeader head;
+ RDMARegister *reg, *registers;
+ RDMACompress *comp;
+ RDMARegisterResult *reg_result;
+ static RDMARegisterResult results[RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE];
+ RDMALocalBlock *block;
+ void *host_addr;
+ int ret = 0;
+ int idx = 0;
+ int count = 0;
+ int i = 0;
+
+ CHECK_ERROR_STATE();
+
+ do {
+ DDDPRINTF("Waiting for next request %" PRIu64 "...\n", flags);
+
+ ret = qemu_rdma_exchange_recv(rdma, &head, RDMA_CONTROL_NONE);
+
+ if (ret < 0) {
+ break;
+ }
+
+ if (head.repeat > RDMA_CONTROL_MAX_COMMANDS_PER_MESSAGE) {
+ fprintf(stderr, "rdma: Too many requests in this message (%d)."
+ "Bailing.\n", head.repeat);
+ ret = -EIO;
+ break;
+ }
+
+ switch (head.type) {
+ case RDMA_CONTROL_COMPRESS:
+ comp = (RDMACompress *) rdma->wr_data[idx].control_curr;
+ network_to_compress(comp);
+
+ DDPRINTF("Zapping zero chunk: %" PRId64
+ " bytes, index %d, offset %" PRId64 "\n",
+ comp->length, comp->block_idx, comp->offset);
+ block = &(rdma->local_ram_blocks.block[comp->block_idx]);
+
+ host_addr = block->local_host_addr +
+ (comp->offset - block->offset);
+
+ ram_handle_compressed(host_addr, comp->value, comp->length);
+ break;
+
+ case RDMA_CONTROL_REGISTER_FINISHED:
+ DDDPRINTF("Current registrations complete.\n");
+ goto out;
+
+ case RDMA_CONTROL_RAM_BLOCKS_REQUEST:
+ DPRINTF("Initial setup info requested.\n");
+
+ if (rdma->pin_all) {
+ ret = qemu_rdma_reg_whole_ram_blocks(rdma);
+ if (ret) {
+ fprintf(stderr, "rdma migration: error dest "
+ "registering ram blocks!\n");
+ goto out;
+ }
+ }
+
+ /*
+ * Dest uses this to prepare to transmit the RAMBlock descriptions
+ * to the source VM after connection setup.
+ * Both sides use the "remote" structure to communicate and update
+ * their "local" descriptions with what was sent.
+ */
+ for (i = 0; i < local->nb_blocks; i++) {
+ rdma->block[i].remote_host_addr =
+ (uint64_t)(local->block[i].local_host_addr);
+
+ if (rdma->pin_all) {
+ rdma->block[i].remote_rkey = local->block[i].mr->rkey;
+ }
+
+ rdma->block[i].offset = local->block[i].offset;
+ rdma->block[i].length = local->block[i].length;
+
+ remote_block_to_network(&rdma->block[i]);
+ }
+
+ blocks.len = rdma->local_ram_blocks.nb_blocks
+ * sizeof(RDMARemoteBlock);
+
+
+ ret = qemu_rdma_post_send_control(rdma,
+ (uint8_t *) rdma->block, &blocks);
+
+ if (ret < 0) {
+ fprintf(stderr, "rdma migration: error sending remote info!\n");
+ goto out;
+ }
+
+ break;
+ case RDMA_CONTROL_REGISTER_REQUEST:
+ DDPRINTF("There are %d registration requests\n", head.repeat);
+
+ reg_resp.repeat = head.repeat;
+ registers = (RDMARegister *) rdma->wr_data[idx].control_curr;
+
+ for (count = 0; count < head.repeat; count++) {
+ uint64_t chunk;
+ uint8_t *chunk_start, *chunk_end;
+
+ reg = ®isters[count];
+ network_to_register(reg);
+
+ reg_result = &results[count];
+
+ DDPRINTF("Registration request (%d): index %d, current_addr %"
+ PRIu64 " chunks: %" PRIu64 "\n", count,
+ reg->current_index, reg->key.current_addr, reg->chunks);
+
+ block = &(rdma->local_ram_blocks.block[reg->current_index]);
+ if (block->is_ram_block) {
+ host_addr = (block->local_host_addr +
+ (reg->key.current_addr - block->offset));
+ chunk = ram_chunk_index(block->local_host_addr,
+ (uint8_t *) host_addr);
+ } else {
+ chunk = reg->key.chunk;
+ host_addr = block->local_host_addr +
+ (reg->key.chunk * (1UL << RDMA_REG_CHUNK_SHIFT));
+ }
+ chunk_start = ram_chunk_start(block, chunk);
+ chunk_end = ram_chunk_end(block, chunk + reg->chunks);
+ if (qemu_rdma_register_and_get_keys(rdma, block,
+ (uint8_t *)host_addr, NULL, ®_result->rkey,
+ chunk, chunk_start, chunk_end)) {
+ fprintf(stderr, "cannot get rkey!\n");
+ ret = -EINVAL;
+ goto out;
+ }
+
+ reg_result->host_addr = (uint64_t) block->local_host_addr;
+
+ DDPRINTF("Registered rkey for this request: %x\n",
+ reg_result->rkey);
+
+ result_to_network(reg_result);
+ }
+
+ ret = qemu_rdma_post_send_control(rdma,
+ (uint8_t *) results, ®_resp);
+
+ if (ret < 0) {
+ fprintf(stderr, "Failed to send control buffer!\n");
+ goto out;
+ }
+ break;
+ case RDMA_CONTROL_UNREGISTER_REQUEST:
+ DDPRINTF("There are %d unregistration requests\n", head.repeat);
+ unreg_resp.repeat = head.repeat;
+ registers = (RDMARegister *) rdma->wr_data[idx].control_curr;
+
+ for (count = 0; count < head.repeat; count++) {
+ reg = ®isters[count];
+ network_to_register(reg);
+
+ DDPRINTF("Unregistration request (%d): "
+ " index %d, chunk %" PRIu64 "\n",
+ count, reg->current_index, reg->key.chunk);
+
+ block = &(rdma->local_ram_blocks.block[reg->current_index]);
+
+ ret = ibv_dereg_mr(block->pmr[reg->key.chunk]);
+ block->pmr[reg->key.chunk] = NULL;
+
+ if (ret != 0) {
+ perror("rdma unregistration chunk failed");
+ ret = -ret;
+ goto out;
+ }
+
+ rdma->total_registrations--;
+
+ DDPRINTF("Unregistered chunk %" PRIu64 " successfully.\n",
+ reg->key.chunk);
+ }
+
+ ret = qemu_rdma_post_send_control(rdma, NULL, &unreg_resp);
+
+ if (ret < 0) {
+ fprintf(stderr, "Failed to send control buffer!\n");
+ goto out;
+ }
+ break;
+ case RDMA_CONTROL_REGISTER_RESULT:
+ fprintf(stderr, "Invalid RESULT message at dest.\n");
+ ret = -EIO;
+ goto out;
+ default:
+ fprintf(stderr, "Unknown control message %s\n",
+ control_desc[head.type]);
+ ret = -EIO;
+ goto out;
+ }
+ } while (1);
+out:
+ if (ret < 0) {
+ rdma->error_state = ret;
+ }
+ return ret;
+}
+
+static int qemu_rdma_registration_start(QEMUFile *f, void *opaque,
+ uint64_t flags)
+{
+ QEMUFileRDMA *rfile = opaque;
+ RDMAContext *rdma = rfile->rdma;
+
+ CHECK_ERROR_STATE();
+
+ DDDPRINTF("start section: %" PRIu64 "\n", flags);
+ qemu_put_be64(f, RAM_SAVE_FLAG_HOOK);
+ qemu_fflush(f);
+
+ return 0;
+}
+
+/*
+ * Inform dest that dynamic registrations are done for now.
+ * First, flush writes, if any.
+ */
+static int qemu_rdma_registration_stop(QEMUFile *f, void *opaque,
+ uint64_t flags)
+{
+ Error *local_err = NULL, **errp = &local_err;
+ QEMUFileRDMA *rfile = opaque;
+ RDMAContext *rdma = rfile->rdma;
+ RDMAControlHeader head = { .len = 0, .repeat = 1 };
+ int ret = 0;
+
+ CHECK_ERROR_STATE();
+
+ qemu_fflush(f);
+ ret = qemu_rdma_drain_cq(f, rdma);
+
+ if (ret < 0) {
+ goto err;
+ }
+
+ if (flags == RAM_CONTROL_SETUP) {
+ RDMAControlHeader resp = {.type = RDMA_CONTROL_RAM_BLOCKS_RESULT };
+ RDMALocalBlocks *local = &rdma->local_ram_blocks;
+ int reg_result_idx, i, j, nb_remote_blocks;
+
+ head.type = RDMA_CONTROL_RAM_BLOCKS_REQUEST;
+ DPRINTF("Sending registration setup for ram blocks...\n");
+
+ /*
+ * Make sure that we parallelize the pinning on both sides.
+ * For very large guests, doing this serially takes a really
+ * long time, so we have to 'interleave' the pinning locally
+ * with the control messages by performing the pinning on this
+ * side before we receive the control response from the other
+ * side that the pinning has completed.
+ */
+ ret = qemu_rdma_exchange_send(rdma, &head, NULL, &resp,
+ ®_result_idx, rdma->pin_all ?
+ qemu_rdma_reg_whole_ram_blocks : NULL);
+ if (ret < 0) {
+ ERROR(errp, "receiving remote info!");
+ return ret;
+ }
+
+ nb_remote_blocks = resp.len / sizeof(RDMARemoteBlock);
+
+ /*
+ * The protocol uses two different sets of rkeys (mutually exclusive):
+ * 1. One key to represent the virtual address of the entire ram block.
+ * (dynamic chunk registration disabled - pin everything with one rkey.)
+ * 2. One to represent individual chunks within a ram block.
+ * (dynamic chunk registration enabled - pin individual chunks.)
+ *
+ * Once the capability is successfully negotiated, the destination transmits
+ * the keys to use (or sends them later) including the virtual addresses
+ * and then propagates the remote ram block descriptions to his local copy.
+ */
+
+ if (local->nb_blocks != nb_remote_blocks) {
+ ERROR(errp, "ram blocks mismatch #1! "
+ "Your QEMU command line parameters are probably "
+ "not identical on both the source and destination.");
+ return -EINVAL;
+ }
+
+ qemu_rdma_move_header(rdma, reg_result_idx, &resp);
+ memcpy(rdma->block,
+ rdma->wr_data[reg_result_idx].control_curr, resp.len);
+ for (i = 0; i < nb_remote_blocks; i++) {
+ network_to_remote_block(&rdma->block[i]);
+
+ /* search local ram blocks */
+ for (j = 0; j < local->nb_blocks; j++) {
+ if (rdma->block[i].offset != local->block[j].offset) {
+ continue;
+ }
+
+ if (rdma->block[i].length != local->block[j].length) {
+ ERROR(errp, "ram blocks mismatch #2! "
+ "Your QEMU command line parameters are probably "
+ "not identical on both the source and destination.");
+ return -EINVAL;
+ }
+ local->block[j].remote_host_addr =
+ rdma->block[i].remote_host_addr;
+ local->block[j].remote_rkey = rdma->block[i].remote_rkey;
+ break;
+ }
+
+ if (j >= local->nb_blocks) {
+ ERROR(errp, "ram blocks mismatch #3! "
+ "Your QEMU command line parameters are probably "
+ "not identical on both the source and destination.");
+ return -EINVAL;
+ }
+ }
+ }
+
+ DDDPRINTF("Sending registration finish %" PRIu64 "...\n", flags);
+
+ head.type = RDMA_CONTROL_REGISTER_FINISHED;
+ ret = qemu_rdma_exchange_send(rdma, &head, NULL, NULL, NULL, NULL);
+
+ if (ret < 0) {
+ goto err;
+ }
+
+ return 0;
+err:
+ rdma->error_state = ret;
+ return ret;
+}
+
+static int qemu_rdma_get_fd(void *opaque)
+{
+ QEMUFileRDMA *rfile = opaque;
+ RDMAContext *rdma = rfile->rdma;
+
+ return rdma->comp_channel->fd;
+}
+
+const QEMUFileOps rdma_read_ops = {
+ .get_buffer = qemu_rdma_get_buffer,
+ .get_fd = qemu_rdma_get_fd,
+ .close = qemu_rdma_close,
+ .hook_ram_load = qemu_rdma_registration_handle,
+};
+
+const QEMUFileOps rdma_write_ops = {
+ .put_buffer = qemu_rdma_put_buffer,
+ .close = qemu_rdma_close,
+ .before_ram_iterate = qemu_rdma_registration_start,
+ .after_ram_iterate = qemu_rdma_registration_stop,
+ .save_page = qemu_rdma_save_page,
+};
+
+static void *qemu_fopen_rdma(RDMAContext *rdma, const char *mode)
+{
+ QEMUFileRDMA *r = g_malloc0(sizeof(QEMUFileRDMA));
+
+ if (qemu_file_mode_is_not_valid(mode)) {
+ return NULL;
+ }
+
+ r->rdma = rdma;
+
+ if (mode[0] == 'w') {
+ r->file = qemu_fopen_ops(r, &rdma_write_ops);
+ } else {
+ r->file = qemu_fopen_ops(r, &rdma_read_ops);
+ }
+
+ return r->file;
+}
+
+static void rdma_accept_incoming_migration(void *opaque)
+{
+ RDMAContext *rdma = opaque;
+ int ret;
+ QEMUFile *f;
+ Error *local_err = NULL, **errp = &local_err;
+
+ DPRINTF("Accepting rdma connection...\n");
+ ret = qemu_rdma_accept(rdma);
+
+ if (ret) {
+ ERROR(errp, "RDMA Migration initialization failed!");
+ return;
+ }
+
+ DPRINTF("Accepted migration\n");
+
+ f = qemu_fopen_rdma(rdma, "rb");
+ if (f == NULL) {
+ ERROR(errp, "could not qemu_fopen_rdma!");
+ qemu_rdma_cleanup(rdma);
+ return;
+ }
+
+ rdma->migration_started_on_destination = 1;
+ process_incoming_migration(f);
+}
+
+void rdma_start_incoming_migration(const char *host_port, Error **errp)
+{
+ int ret;
+ RDMAContext *rdma;
+ Error *local_err = NULL;
+
+ DPRINTF("Starting RDMA-based incoming migration\n");
+ rdma = qemu_rdma_data_init(host_port, &local_err);
+
+ if (rdma == NULL) {
+ goto err;
+ }
+
+ ret = qemu_rdma_dest_init(rdma, &local_err);
+
+ if (ret) {
+ goto err;
+ }
+
+ DPRINTF("qemu_rdma_dest_init success\n");
+
+ ret = rdma_listen(rdma->listen_id, 5);
+
+ if (ret) {
+ ERROR(errp, "listening on socket!");
+ goto err;
+ }
+
+ DPRINTF("rdma_listen success\n");
+
+ qemu_set_fd_handler2(rdma->channel->fd, NULL,
+ rdma_accept_incoming_migration, NULL,
+ (void *)(intptr_t) rdma);
+ return;
+err:
+ error_propagate(errp, local_err);
+ g_free(rdma);
+}
+
+void rdma_start_outgoing_migration(void *opaque,
+ const char *host_port, Error **errp)
+{
+ MigrationState *s = opaque;
+ Error *local_err = NULL, **temp = &local_err;
+ RDMAContext *rdma = qemu_rdma_data_init(host_port, &local_err);
+ int ret = 0;
+
+ if (rdma == NULL) {
+ ERROR(temp, "Failed to initialize RDMA data structures! %d", ret);
+ goto err;
+ }
+
+ ret = qemu_rdma_source_init(rdma, &local_err,
+ s->enabled_capabilities[MIGRATION_CAPABILITY_RDMA_PIN_ALL]);
+
+ if (ret) {
+ goto err;
+ }
+
+ DPRINTF("qemu_rdma_source_init success\n");
+ ret = qemu_rdma_connect(rdma, &local_err);
+
+ if (ret) {
+ goto err;
+ }
+
+ DPRINTF("qemu_rdma_source_connect success\n");
+
+ s->file = qemu_fopen_rdma(rdma, "wb");
+ migrate_fd_connect(s);
+ return;
+err:
+ error_propagate(errp, local_err);
+ g_free(rdma);
+ migrate_fd_error(s);
+}
--- /dev/null
+/*
+ * QEMU live migration
+ *
+ * Copyright IBM, Corp. 2008
+ *
+ * Authors:
+ * Anthony Liguori <aliguori@us.ibm.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
+ */
+
+#include <string.h>
+
+#include "qemu-common.h"
+#include "qemu/error-report.h"
+#include "qemu/sockets.h"
+#include "migration/migration.h"
+#include "migration/qemu-file.h"
+#include "block/block.h"
+#include "qemu/main-loop.h"
+
+//#define DEBUG_MIGRATION_TCP
+
+#ifdef DEBUG_MIGRATION_TCP
+#define DPRINTF(fmt, ...) \
+ do { printf("migration-tcp: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+static void tcp_wait_for_connect(int fd, Error *err, void *opaque)
+{
+ MigrationState *s = opaque;
+
+ if (fd < 0) {
+ DPRINTF("migrate connect error: %s\n", error_get_pretty(err));
+ s->file = NULL;
+ migrate_fd_error(s);
+ } else {
+ DPRINTF("migrate connect success\n");
+ s->file = qemu_fopen_socket(fd, "wb");
+ migrate_fd_connect(s);
+ }
+}
+
+void tcp_start_outgoing_migration(MigrationState *s, const char *host_port, Error **errp)
+{
+ inet_nonblocking_connect(host_port, tcp_wait_for_connect, s, errp);
+}
+
+static void tcp_accept_incoming_migration(void *opaque)
+{
+ struct sockaddr_in addr;
+ socklen_t addrlen = sizeof(addr);
+ int s = (intptr_t)opaque;
+ QEMUFile *f;
+ int c, err;
+
+ do {
+ c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
+ err = socket_error();
+ } while (c < 0 && err == EINTR);
+ qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
+ closesocket(s);
+
+ DPRINTF("accepted migration\n");
+
+ if (c < 0) {
+ error_report("could not accept migration connection (%s)",
+ strerror(err));
+ return;
+ }
+
+ f = qemu_fopen_socket(c, "rb");
+ if (f == NULL) {
+ error_report("could not qemu_fopen socket");
+ goto out;
+ }
+
+ process_incoming_migration(f);
+ return;
+
+out:
+ closesocket(c);
+}
+
+void tcp_start_incoming_migration(const char *host_port, Error **errp)
+{
+ int s;
+
+ s = inet_listen(host_port, NULL, 256, SOCK_STREAM, 0, errp);
+ if (s < 0) {
+ return;
+ }
+
+ qemu_set_fd_handler2(s, NULL, tcp_accept_incoming_migration, NULL,
+ (void *)(intptr_t)s);
+}
--- /dev/null
+/*
+ * QEMU live migration via Unix Domain Sockets
+ *
+ * Copyright Red Hat, Inc. 2009
+ *
+ * Authors:
+ * Chris Lalancette <clalance@redhat.com>
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2. See
+ * the COPYING file in the top-level directory.
+ *
+ * Contributions after 2012-01-13 are licensed under the terms of the
+ * GNU GPL, version 2 or (at your option) any later version.
+ */
+
+#include <string.h>
+
+#include "qemu-common.h"
+#include "qemu/error-report.h"
+#include "qemu/sockets.h"
+#include "qemu/main-loop.h"
+#include "migration/migration.h"
+#include "migration/qemu-file.h"
+#include "block/block.h"
+
+//#define DEBUG_MIGRATION_UNIX
+
+#ifdef DEBUG_MIGRATION_UNIX
+#define DPRINTF(fmt, ...) \
+ do { printf("migration-unix: " fmt, ## __VA_ARGS__); } while (0)
+#else
+#define DPRINTF(fmt, ...) \
+ do { } while (0)
+#endif
+
+static void unix_wait_for_connect(int fd, Error *err, void *opaque)
+{
+ MigrationState *s = opaque;
+
+ if (fd < 0) {
+ DPRINTF("migrate connect error: %s\n", error_get_pretty(err));
+ s->file = NULL;
+ migrate_fd_error(s);
+ } else {
+ DPRINTF("migrate connect success\n");
+ s->file = qemu_fopen_socket(fd, "wb");
+ migrate_fd_connect(s);
+ }
+}
+
+void unix_start_outgoing_migration(MigrationState *s, const char *path, Error **errp)
+{
+ unix_nonblocking_connect(path, unix_wait_for_connect, s, errp);
+}
+
+static void unix_accept_incoming_migration(void *opaque)
+{
+ struct sockaddr_un addr;
+ socklen_t addrlen = sizeof(addr);
+ int s = (intptr_t)opaque;
+ QEMUFile *f;
+ int c, err;
+
+ do {
+ c = qemu_accept(s, (struct sockaddr *)&addr, &addrlen);
+ err = errno;
+ } while (c < 0 && err == EINTR);
+ qemu_set_fd_handler2(s, NULL, NULL, NULL, NULL);
+ close(s);
+
+ DPRINTF("accepted migration\n");
+
+ if (c < 0) {
+ error_report("could not accept migration connection (%s)",
+ strerror(err));
+ return;
+ }
+
+ f = qemu_fopen_socket(c, "rb");
+ if (f == NULL) {
+ error_report("could not qemu_fopen socket");
+ goto out;
+ }
+
+ process_incoming_migration(f);
+ return;
+
+out:
+ close(c);
+}
+
+void unix_start_incoming_migration(const char *path, Error **errp)
+{
+ int s;
+
+ s = unix_listen(path, NULL, 0, errp);
+ if (s < 0) {
+ return;
+ }
+
+ qemu_set_fd_handler2(s, NULL, unix_accept_incoming_migration, NULL,
+ (void *)(intptr_t)s);
+}