+++ /dev/null
-/******************************************************************************
- * fs-front.c
- *
- * Frontend driver for FS split device driver.
- *
- * Copyright (c) 2007, Grzegorz Milos, <gm281@cam.ac.uk>.
- *
- * Permission is hereby granted, free of charge, to any person obtaining a copy
- * of this software and associated documentation files (the "Software"), to
- * deal in the Software without restriction, including without limitation the
- * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
- * sell copies of the Software, and to permit persons to whom the Software is
- * furnished to do so, subject to the following conditions:
- *
- * The above copyright notice and this permission notice shall be included in
- * all copies or substantial portions of the Software.
- *
- * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
- * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
- * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
- * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
- * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
- * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
- * DEALINGS IN THE SOFTWARE.
- */
-
-#undef NDEBUG
-#include <stdint.h>
-#include <mini-os/os.h>
-#include <mini-os/list.h>
-#include <mini-os/xmalloc.h>
-#include <mini-os/xenbus.h>
-#include <mini-os/gnttab.h>
-#include <mini-os/events.h>
-#include <xen/io/fsif.h>
-#include <mini-os/fs.h>
-#include <mini-os/sched.h>
-
-#define preempt_disable()
-#define preempt_enable()
-#define cmpxchg(p,o,n) synch_cmpxchg(p,o,n)
-
-
-#ifdef FS_DEBUG
-#define DEBUG(_f, _a...) \
- printk("MINI_OS(file=fs-front.c, line=%d) " _f "\n", __LINE__, ## _a)
-#else
-#define DEBUG(_f, _a...) ((void)0)
-#endif
-
-
-struct fs_request;
-struct fs_import *fs_import;
-void *alloc_buffer_page(struct fs_request *req, domid_t domid, grant_ref_t *gref);
-void free_buffer_page(struct fs_request *req);
-
-/******************************************************************************/
-/* RING REQUEST/RESPONSES HANDLING */
-/******************************************************************************/
-
-struct fs_request
-{
- void *private1; /* Specific to request type */
- void *private2;
- struct thread *thread; /* Thread blocked on this request */
- struct fsif_response shadow_rsp; /* Response copy writen by the
- interrupt handler */
-};
-
-struct fs_rw_gnts
-{
- /* TODO 16 bit? */
- int count;
- grant_ref_t grefs[FSIF_NR_READ_GNTS];
- void *pages[FSIF_NR_READ_GNTS];
-};
-
-/* Ring operations:
- * FSIF ring is used differently to Linux-like split devices. This stems from
- * the fact that no I/O request queue is present. The use of some of the macros
- * defined in ring.h is not allowed, in particular:
- * RING_PUSH_REQUESTS_AND_CHECK_NOTIFY cannot be used.
- *
- * The protocol used for FSIF ring is described below:
- *
- * In order to reserve a request the frontend:
- * a) saves current frontend_ring->req_prod_pvt into a local variable
- * b) checks that there are free request using the local req_prod_pvt
- * c) tries to reserve the request using cmpxchg on frontend_ring->req_prod_pvt
- * if cmpxchg fails, it means that someone reserved the request, start from
- * a)
- *
- * In order to commit a request to the shared ring:
- * a) cmpxchg shared_ring->req_prod from local req_prod_pvt to req_prod_pvt+1
- * Loop if unsuccessful.
- * NOTE: Request should be commited to the shared ring as quickly as possible,
- * because otherwise other threads might busy loop trying to commit next
- * requests. It also follows that preemption should be disabled, if
- * possible, for the duration of the request construction.
- */
-
-/* Number of free requests (for use on front side only). */
-#define FS_RING_FREE_REQUESTS(_r, _req_prod_pvt) \
- (RING_SIZE(_r) - (_req_prod_pvt - (_r)->rsp_cons))
-
-
-
-static RING_IDX reserve_fsif_request(struct fs_import *import)
-{
- RING_IDX idx;
-
- down(&import->reqs_sem);
- preempt_disable();
-again:
- /* We will attempt to reserve slot idx */
- idx = import->ring.req_prod_pvt;
- ASSERT (FS_RING_FREE_REQUESTS(&import->ring, idx));
- /* Attempt to reserve */
- if(cmpxchg(&import->ring.req_prod_pvt, idx, idx+1) != idx)
- goto again;
-
- return idx;
-}
-
-static void commit_fsif_request(struct fs_import *import, RING_IDX idx)
-{
- while(cmpxchg(&import->ring.sring->req_prod, idx, idx+1) != idx)
- {
- printk("Failed to commit a request: req_prod=%d, idx=%d\n",
- import->ring.sring->req_prod, idx);
- }
- preempt_enable();
-
- /* NOTE: we cannot do anything clever about rsp_event, to hold off
- * notifications, because we don't know if we are a single request (in which
- * case we have to notify always), or a part of a larger request group
- * (when, in some cases, notification isn't required) */
- notify_remote_via_evtchn(import->local_port);
-}
-
-
-
-static inline void add_id_to_freelist(unsigned int id,unsigned short* freelist)
-{
- unsigned int old_id, new_id;
-
-again:
- old_id = freelist[0];
- /* Note: temporal inconsistency, since freelist[0] can be changed by someone
- * else, but we are a sole owner of freelist[id + 1], it's OK. */
- freelist[id + 1] = old_id;
- new_id = id;
- if(cmpxchg(&freelist[0], old_id, new_id) != old_id)
- {
- printk("Cmpxchg on freelist add failed.\n");
- goto again;
- }
-}
-
-/* always call reserve_fsif_request(import) before this, to protect from
- * depletion. */
-static inline unsigned short get_id_from_freelist(unsigned short* freelist)
-{
- unsigned int old_id, new_id;
-
-again:
- old_id = freelist[0];
- new_id = freelist[old_id + 1];
- if(cmpxchg(&freelist[0], old_id, new_id) != old_id)
- {
- printk("Cmpxchg on freelist remove failed.\n");
- goto again;
- }
-
- return old_id;
-}
-
-/******************************************************************************/
-/* END OF RING REQUEST/RESPONSES HANDLING */
-/******************************************************************************/
-
-
-
-/******************************************************************************/
-/* INDIVIDUAL FILE OPERATIONS */
-/******************************************************************************/
-int fs_open(struct fs_import *import, char *file)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- grant_ref_t gref;
- void *buffer;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int fd;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_open call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- buffer = alloc_buffer_page(fsr, import->dom_id, &gref);
- DEBUG("gref id=%d\n", gref);
- fsr->thread = current;
- sprintf(buffer, "%s", file);
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_FILE_OPEN;
- req->id = priv_req_id;
- req->u.fopen.gref = gref;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- fd = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("The following FD returned: %d\n", fd);
- free_buffer_page(fsr);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return fd;
-}
-
-int fs_close(struct fs_import *import, int fd)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int ret;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_close call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- fsr->thread = current;
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_FILE_CLOSE;
- req->id = priv_req_id;
- req->u.fclose.fd = fd;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("Close returned: %d\n", ret);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-ssize_t fs_read(struct fs_import *import, int fd, void *buf,
- ssize_t len, ssize_t offset)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- struct fs_rw_gnts gnts;
- RING_IDX back_req_id;
- struct fsif_request *req;
- ssize_t ret;
- int i;
-
- if (!import)
- return -1;
-
- BUG_ON(len > PAGE_SIZE * FSIF_NR_READ_GNTS);
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_read call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_FILE_READ;
- req->id = priv_req_id;
- req->u.fread.fd = fd;
- req->u.fread.len = len;
- req->u.fread.offset = offset;
-
-
- ASSERT(len > 0);
- gnts.count = ((len - 1) / PAGE_SIZE) + 1;
- for(i=0; i<gnts.count; i++)
- {
- gnts.pages[i] = (void *)alloc_page();
- gnts.grefs[i] = gnttab_grant_access(import->dom_id,
- virt_to_mfn(gnts.pages[i]),
- 0);
- memset(gnts.pages[i], 0, PAGE_SIZE);
- req->u.fread.grefs[i] = gnts.grefs[i];
- }
- fsr->thread = current;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (ssize_t)fsr->shadow_rsp.u.ret_val;
- DEBUG("The following ret value returned %d\n", ret);
- if(ret > 0)
- {
- ssize_t to_copy = ret, current_copy;
- for(i=0; i<gnts.count; i++)
- {
- gnttab_end_access(gnts.grefs[i]);
- current_copy = to_copy > PAGE_SIZE ? PAGE_SIZE : to_copy;
- if(current_copy > 0)
- memcpy(buf, gnts.pages[i], current_copy);
- to_copy -= current_copy;
- buf = (char*) buf + current_copy;
- free_page(gnts.pages[i]);
- }
- }
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-ssize_t fs_write(struct fs_import *import, int fd, void *buf,
- ssize_t len, ssize_t offset)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- struct fs_rw_gnts gnts;
- RING_IDX back_req_id;
- struct fsif_request *req;
- ssize_t ret, to_copy;
- int i;
-
- if (!import)
- return -1;
-
- BUG_ON(len > PAGE_SIZE * FSIF_NR_WRITE_GNTS);
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_read call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_FILE_WRITE;
- req->id = priv_req_id;
- req->u.fwrite.fd = fd;
- req->u.fwrite.len = len;
- req->u.fwrite.offset = offset;
-
- ASSERT(len > 0);
- gnts.count = ((len - 1) / PAGE_SIZE) + 1;
- to_copy = len;
- for(i=0; i<gnts.count; i++)
- {
- int current_copy = (to_copy > PAGE_SIZE ? PAGE_SIZE : to_copy);
- gnts.pages[i] = (void *)alloc_page();
- gnts.grefs[i] = gnttab_grant_access(import->dom_id,
- virt_to_mfn(gnts.pages[i]),
- 0);
- memcpy(gnts.pages[i], buf, current_copy);
- if(current_copy < PAGE_SIZE)
- memset((char *)gnts.pages[i] + current_copy,
- 0,
- PAGE_SIZE - current_copy);
- req->u.fwrite.grefs[i] = gnts.grefs[i];
- to_copy -= current_copy;
- buf = (char*) buf + current_copy;
- }
- fsr->thread = current;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (ssize_t)fsr->shadow_rsp.u.ret_val;
- DEBUG("The following ret value returned %d\n", ret);
- for(i=0; i<gnts.count; i++)
- {
- gnttab_end_access(gnts.grefs[i]);
- free_page(gnts.pages[i]);
- }
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-int fs_stat(struct fs_import *import,
- int fd,
- struct fsif_stat_response *stat)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int ret;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_stat call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- fsr->thread = current;
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_STAT;
- req->id = priv_req_id;
- req->u.fstat.fd = fd;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("Following ret from fstat: %d\n", ret);
- memcpy(stat,
- &fsr->shadow_rsp.u.fstat,
- sizeof(struct fsif_stat_response));
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-int fs_truncate(struct fs_import *import,
- int fd,
- int64_t length)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int ret;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_truncate call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- fsr->thread = current;
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_FILE_TRUNCATE;
- req->id = priv_req_id;
- req->u.ftruncate.fd = fd;
- req->u.ftruncate.length = length;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("Following ret from ftruncate: %d\n", ret);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-int fs_remove(struct fs_import *import, char *file)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- grant_ref_t gref;
- void *buffer;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int ret;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_open call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- buffer = alloc_buffer_page(fsr, import->dom_id, &gref);
- DEBUG("gref=%d\n", gref);
- fsr->thread = current;
- sprintf(buffer, "%s", file);
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_REMOVE;
- req->id = priv_req_id;
- req->u.fremove.gref = gref;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("The following ret: %d\n", ret);
- free_buffer_page(fsr);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-
-int fs_rename(struct fs_import *import,
- char *old_file_name,
- char *new_file_name)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- grant_ref_t gref;
- void *buffer;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int ret;
- char old_header[] = "old: ";
- char new_header[] = "new: ";
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_open call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- buffer = alloc_buffer_page(fsr, import->dom_id, &gref);
- DEBUG("gref=%d\n", gref);
- fsr->thread = current;
- sprintf(buffer, "%s%s%c%s%s",
- old_header, old_file_name, '\0', new_header, new_file_name);
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_RENAME;
- req->id = priv_req_id;
- req->u.frename.gref = gref;
- req->u.frename.old_name_offset = strlen(old_header);
- req->u.frename.new_name_offset = strlen(old_header) +
- strlen(old_file_name) +
- strlen(new_header) +
- 1 /* Accouning for the additional
- end of string character */;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("The following ret: %d\n", ret);
- free_buffer_page(fsr);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-int fs_create(struct fs_import *import, char *name,
- int8_t directory, int32_t mode)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- grant_ref_t gref;
- void *buffer;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int ret;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_create call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- buffer = alloc_buffer_page(fsr, import->dom_id, &gref);
- DEBUG("gref=%d\n", gref);
- fsr->thread = current;
- sprintf(buffer, "%s", name);
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_CREATE;
- req->id = priv_req_id;
- req->u.fcreate.gref = gref;
- req->u.fcreate.directory = directory;
- req->u.fcreate.mode = mode;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("The following ret: %d\n", ret);
- free_buffer_page(fsr);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-char** fs_list(struct fs_import *import, char *name,
- int32_t offset, int32_t *nr_files, int *has_more)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- grant_ref_t gref;
- void *buffer;
- RING_IDX back_req_id;
- struct fsif_request *req;
- char **files, *current_file;
- int i;
-
- if (!import)
- return NULL;
-
- DEBUG("Different masks: NR_FILES=(%llx, %d), ERROR=(%llx, %d), HAS_MORE(%llx, %d)\n",
- NR_FILES_MASK, NR_FILES_SHIFT, ERROR_MASK, ERROR_SHIFT, HAS_MORE_FLAG, HAS_MORE_SHIFT);
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_list call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- buffer = alloc_buffer_page(fsr, import->dom_id, &gref);
- DEBUG("gref=%d\n", gref);
- fsr->thread = current;
- sprintf(buffer, "%s", name);
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_DIR_LIST;
- req->id = priv_req_id;
- req->u.flist.gref = gref;
- req->u.flist.offset = offset;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- *nr_files = (fsr->shadow_rsp.u.ret_val & NR_FILES_MASK) >> NR_FILES_SHIFT;
- files = NULL;
- if(*nr_files <= 0) goto exit;
- files = malloc(sizeof(char*) * (*nr_files));
- current_file = buffer;
- for(i=0; i<*nr_files; i++)
- {
- files[i] = strdup(current_file);
- current_file += strlen(current_file) + 1;
- }
- if(has_more != NULL)
- *has_more = fsr->shadow_rsp.u.ret_val & HAS_MORE_FLAG;
- free_buffer_page(fsr);
- add_id_to_freelist(priv_req_id, import->freelist);
-exit:
- return files;
-}
-
-int fs_chmod(struct fs_import *import, int fd, int32_t mode)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int ret;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_chmod call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- fsr->thread = current;
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_CHMOD;
- req->id = priv_req_id;
- req->u.fchmod.fd = fd;
- req->u.fchmod.mode = mode;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("The following returned: %d\n", ret);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-int64_t fs_space(struct fs_import *import, char *location)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- grant_ref_t gref;
- void *buffer;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int64_t ret;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_space is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- buffer = alloc_buffer_page(fsr, import->dom_id, &gref);
- DEBUG("gref=%d\n", gref);
- fsr->thread = current;
- sprintf(buffer, "%s", location);
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_FS_SPACE;
- req->id = priv_req_id;
- req->u.fspace.gref = gref;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int64_t)fsr->shadow_rsp.u.ret_val;
- DEBUG("The following returned: %lld\n", ret);
- free_buffer_page(fsr);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-int fs_sync(struct fs_import *import, int fd)
-{
- struct fs_request *fsr;
- unsigned short priv_req_id;
- RING_IDX back_req_id;
- struct fsif_request *req;
- int ret;
-
- if (!import)
- return -1;
-
- /* Prepare request for the backend */
- back_req_id = reserve_fsif_request(import);
- DEBUG("Backend request id=%d\n", back_req_id);
-
- /* Prepare our private request structure */
- priv_req_id = get_id_from_freelist(import->freelist);
- DEBUG("Request id for fs_sync call is: %d\n", priv_req_id);
- fsr = &import->requests[priv_req_id];
- fsr->thread = current;
-
- req = RING_GET_REQUEST(&import->ring, back_req_id);
- req->type = REQ_FILE_SYNC;
- req->id = priv_req_id;
- req->u.fsync.fd = fd;
-
- /* Set blocked flag before commiting the request, thus avoiding missed
- * response race */
- block(current);
- commit_fsif_request(import, back_req_id);
- schedule();
-
- /* Read the response */
- ret = (int)fsr->shadow_rsp.u.ret_val;
- DEBUG("Close returned: %d\n", ret);
- add_id_to_freelist(priv_req_id, import->freelist);
-
- return ret;
-}
-
-
-/******************************************************************************/
-/* END OF INDIVIDUAL FILE OPERATIONS */
-/******************************************************************************/
-
-void *alloc_buffer_page(struct fs_request *req, domid_t domid, grant_ref_t *gref)
-{
- void *page;
-
- page = (void *)alloc_page();
- *gref = gnttab_grant_access(domid, virt_to_mfn(page), 0);
- req->private1 = page;
- req->private2 = (void *)(uintptr_t)(*gref);
-
- return page;
-}
-
-void free_buffer_page(struct fs_request *req)
-{
- gnttab_end_access((grant_ref_t)(uintptr_t)req->private2);
- free_page(req->private1);
-}
-
-static void fsfront_handler(evtchn_port_t port, struct pt_regs *regs, void *data)
-{
- struct fs_import *import = (struct fs_import*)data;
- static int in_irq = 0;
- RING_IDX cons, rp;
- int more;
-
- /* Check for non-reentrance */
- BUG_ON(in_irq);
- in_irq = 1;
-
- DEBUG("Event from import [%d:%d].\n", import->dom_id, import->export_id);
-moretodo:
- rp = import->ring.sring->rsp_prod;
- rmb(); /* Ensure we see queued responses up to 'rp'. */
- cons = import->ring.rsp_cons;
- while (cons != rp)
- {
- struct fsif_response *rsp;
- struct fs_request *req;
-
- rsp = RING_GET_RESPONSE(&import->ring, cons);
- DEBUG("Response at idx=%d to request id=%d, ret_val=%lx\n",
- cons, rsp->id, rsp->u.ret_val);
- req = &import->requests[rsp->id];
- memcpy(&req->shadow_rsp, rsp, sizeof(struct fsif_response));
- DEBUG("Waking up: %s\n", req->thread->name);
- wake(req->thread);
-
- cons++;
- up(&import->reqs_sem);
- }
-
- import->ring.rsp_cons = rp;
- RING_FINAL_CHECK_FOR_RESPONSES(&import->ring, more);
- if(more) goto moretodo;
-
- in_irq = 0;
-}
-
-static void alloc_request_table(struct fs_import *import)
-{
- struct fs_request *requests;
- int i;
-
- BUG_ON(import->nr_entries <= 0);
- printk("Allocating request array for import %d, nr_entries = %d.\n",
- import->import_id, import->nr_entries);
- requests = xmalloc_array(struct fs_request, import->nr_entries);
- import->freelist = xmalloc_array(unsigned short, import->nr_entries + 1);
- memset(import->freelist, 0, sizeof(unsigned short) * (import->nr_entries + 1));
- for(i=0; i<import->nr_entries; i++)
- add_id_to_freelist(i, import->freelist);
- import->requests = requests;
-}
-
-
-/******************************************************************************/
-/* FS TESTS */
-/******************************************************************************/
-
-
-void test_fs_import(void *data)
-{
- struct fs_import *import = (struct fs_import *)data;
- int ret, fd, i, repeat_count;
- int32_t nr_files;
- char buffer[1024];
- ssize_t offset;
- char **files;
- long ret64;
- struct fsif_stat_response stat;
-
- repeat_count = 10;
- /* Sleep for 1s and then try to open a file */
- msleep(1000);
-again:
- ret = fs_create(import, "mini-os-created-directory", 1, 0777);
- printk("Directory create: %d\n", ret);
-
- sprintf(buffer, "mini-os-created-directory/mini-os-created-file-%d",
- repeat_count);
- ret = fs_create(import, buffer, 0, 0666);
- printk("File create: %d\n", ret);
-
- fd = fs_open(import, buffer);
- printk("File descriptor: %d\n", fd);
- if(fd < 0) return;
-
- offset = 0;
- for(i=0; i<10; i++)
- {
- sprintf(buffer, "Current time is: %lld\n", NOW());
- ret = fs_write(import, fd, buffer, strlen(buffer), offset);
- printk("Writen current time (%d)\n", ret);
- if(ret < 0)
- return;
- offset += ret;
- }
- ret = fs_stat(import, fd, &stat);
- printk("Ret after stat: %d\n", ret);
- printk(" st_mode=%o\n", stat.stat_mode);
- printk(" st_uid =%d\n", stat.stat_uid);
- printk(" st_gid =%d\n", stat.stat_gid);
- printk(" st_size=%ld\n", stat.stat_size);
- printk(" st_atime=%ld\n", stat.stat_atime);
- printk(" st_mtime=%ld\n", stat.stat_mtime);
- printk(" st_ctime=%ld\n", stat.stat_ctime);
-
- ret = fs_close(import, fd);
- printk("Closed fd: %d, ret=%d\n", fd, ret);
-
- printk("Listing files in /\n");
- files = fs_list(import, "/", 0, &nr_files, NULL);
- for(i=0; i<nr_files; i++)
- printk(" files[%d] = %s\n", i, files[i]);
-
- ret64 = fs_space(import, "/");
- printk("Free space: %lld (=%lld Mb)\n", ret64, (ret64 >> 20));
- repeat_count--;
- if(repeat_count > 0)
- goto again;
-
-}
-
-#if 0
-// char *content = (char *)alloc_page();
- int fd, ret;
-// int read;
- char write_string[] = "\"test data written from minios\"";
- struct fsif_stat_response stat;
- char **files;
- int32_t nr_files, i;
- int64_t ret64;
-
-
- fd = fs_open(import, "test-export-file");
-// read = fs_read(import, fd, content, PAGE_SIZE, 0);
-// printk("Read: %d bytes\n", read);
-// content[read] = '\0';
-// printk("Value: %s\n", content);
- ret = fs_write(import, fd, write_string, strlen(write_string), 0);
- printk("Ret after write: %d\n", ret);
- ret = fs_stat(import, fd, &stat);
- printk("Ret after stat: %d\n", ret);
- printk(" st_mode=%o\n", stat.stat_mode);
- printk(" st_uid =%d\n", stat.stat_uid);
- printk(" st_gid =%d\n", stat.stat_gid);
- printk(" st_size=%ld\n", stat.stat_size);
- printk(" st_atime=%ld\n", stat.stat_atime);
- printk(" st_mtime=%ld\n", stat.stat_mtime);
- printk(" st_ctime=%ld\n", stat.stat_ctime);
- ret = fs_truncate(import, fd, 30);
- printk("Ret after truncate: %d\n", ret);
- ret = fs_remove(import, "test-to-remove/test-file");
- printk("Ret after remove: %d\n", ret);
- ret = fs_remove(import, "test-to-remove");
- printk("Ret after remove: %d\n", ret);
- ret = fs_chmod(import, fd, 0700);
- printk("Ret after chmod: %d\n", ret);
- ret = fs_sync(import, fd);
- printk("Ret after sync: %d\n", ret);
- ret = fs_close(import, fd);
- //ret = fs_rename(import, "test-export-file", "renamed-test-export-file");
- //printk("Ret after rename: %d\n", ret);
- ret = fs_create(import, "created-dir", 1, 0777);
- printk("Ret after dir create: %d\n", ret);
- ret = fs_create(import, "created-dir/created-file", 0, 0777);
- printk("Ret after file create: %d\n", ret);
- files = fs_list(import, "/", 15, &nr_files, NULL);
- for(i=0; i<nr_files; i++)
- printk(" files[%d] = %s\n", i, files[i]);
- ret64 = fs_space(import, "created-dir");
- printk("Ret after space: %lld\n", ret64);
-
-#endif
-
-
-/******************************************************************************/
-/* END OF FS TESTS */
-/******************************************************************************/
-
-static int init_fs_import(struct fs_import *import)
-{
- char *err;
- xenbus_transaction_t xbt;
- char nodename[1024], r_nodename[1024], token[128], *message = NULL;
- struct fsif_sring *sring;
- int i, retry = 0;
- domid_t self_id;
- xenbus_event_queue events = NULL;
-
- printk("Initialising FS fortend to backend dom %d\n", import->dom_id);
- /* Allocate page for the shared ring */
- sring = (struct fsif_sring*) alloc_pages(FSIF_RING_SIZE_ORDER);
- memset(sring, 0, PAGE_SIZE * FSIF_RING_SIZE_PAGES);
-
- /* Init the shared ring */
- SHARED_RING_INIT(sring);
- ASSERT(FSIF_NR_READ_GNTS == FSIF_NR_WRITE_GNTS);
-
- /* Init private frontend ring */
- FRONT_RING_INIT(&import->ring, sring, PAGE_SIZE * FSIF_RING_SIZE_PAGES);
- import->nr_entries = import->ring.nr_ents;
-
- /* Allocate table of requests */
- alloc_request_table(import);
- init_SEMAPHORE(&import->reqs_sem, import->nr_entries);
-
- /* Grant access to the shared ring */
- for(i=0; i<FSIF_RING_SIZE_PAGES; i++)
- import->gnt_refs[i] =
- gnttab_grant_access(import->dom_id,
- virt_to_mfn((char *)sring + i * PAGE_SIZE),
- 0);
-
- /* Allocate event channel */
- BUG_ON(evtchn_alloc_unbound(import->dom_id,
- fsfront_handler,
- //ANY_CPU,
- import,
- &import->local_port));
- unmask_evtchn(import->local_port);
-
-
- self_id = xenbus_get_self_id();
- /* Write the frontend info to a node in our Xenbus */
- sprintf(nodename, "/local/domain/%d/device/vfs/%d",
- self_id, import->import_id);
-
-again:
- err = xenbus_transaction_start(&xbt);
- if (err) {
- printk("starting transaction\n");
- free(err);
- }
-
- err = xenbus_printf(xbt,
- nodename,
- "ring-size",
- "%u",
- FSIF_RING_SIZE_PAGES);
- if (err) {
- message = "writing ring-size";
- goto abort_transaction;
- }
-
- for(i=0; i<FSIF_RING_SIZE_PAGES; i++)
- {
- sprintf(r_nodename, "ring-ref-%d", i);
- err = xenbus_printf(xbt,
- nodename,
- r_nodename,
- "%u",
- import->gnt_refs[i]);
- if (err) {
- message = "writing ring-refs";
- goto abort_transaction;
- }
- }
-
- err = xenbus_printf(xbt,
- nodename,
- "event-channel",
- "%u",
- import->local_port);
- if (err) {
- message = "writing event-channel";
- goto abort_transaction;
- }
-
- err = xenbus_printf(xbt, nodename, "state", STATE_READY, 0xdeadbeef);
- if (err) free(err);
-
- err = xenbus_transaction_end(xbt, 0, &retry);
- if (err) free(err);
- if (retry) {
- goto again;
- printk("completing transaction\n");
- }
-
- /* Now, when our node is prepared we write request in the exporting domain
- * */
- printk("Our own id is %d\n", self_id);
- sprintf(r_nodename,
- "/local/domain/%d/backend/vfs/exports/requests/%d/%d/frontend",
- import->dom_id, self_id, import->export_id);
- BUG_ON(xenbus_write(XBT_NIL, r_nodename, nodename));
-
- goto done;
-
-abort_transaction:
- free(err);
- err = xenbus_transaction_end(xbt, 1, &retry);
- if (err) free(err);
-
-done:
-
-#define WAIT_PERIOD 10 /* Wait period in ms */
-#define MAX_WAIT 10 /* Max number of WAIT_PERIODs */
- import->backend = NULL;
- sprintf(r_nodename, "%s/backend", nodename);
-
- for(retry = MAX_WAIT; retry > 0; retry--)
- {
- xenbus_read(XBT_NIL, r_nodename, &import->backend);
- if(import->backend)
- {
- printk("Backend found at %s\n", import->backend);
- break;
- }
- msleep(WAIT_PERIOD);
- }
-
- if(!import->backend)
- {
- printk("No backend available.\n");
- /* TODO - cleanup datastructures/xenbus */
- return 0;
- }
- sprintf(r_nodename, "%s/state", import->backend);
- sprintf(token, "fs-front-%d", import->import_id);
- /* The token will not be unique if multiple imports are inited */
- xenbus_watch_path_token(XBT_NIL, r_nodename, r_nodename, &events);
- err = xenbus_wait_for_value(r_nodename, STATE_READY, &events);
- if (err) free(err);
- xenbus_unwatch_path_token(XBT_NIL, r_nodename, r_nodename);
- printk("Backend ready.\n");
-
- //create_thread("fs-tester", test_fs_import, import);
-
- return 1;
-}
-
-static void add_export(struct minios_list_head *exports, unsigned int domid)
-{
- char node[1024], **exports_list = NULL, *ret_msg;
- int j = 0;
- static int import_id = 0;
-
- sprintf(node, "/local/domain/%d/backend/vfs/exports", domid);
- ret_msg = xenbus_ls(XBT_NIL, node, &exports_list);
- if (ret_msg && strcmp(ret_msg, "ENOENT"))
- printk("couldn't read %s: %s\n", node, ret_msg);
- while(exports_list && exports_list[j])
- {
- struct fs_import *import;
- int export_id = -1;
-
- sscanf(exports_list[j], "%d", &export_id);
- if(export_id >= 0)
- {
- import = xmalloc(struct fs_import);
- import->dom_id = domid;
- import->export_id = export_id;
- import->import_id = import_id++;
- MINIOS_INIT_LIST_HEAD(&import->list);
- minios_list_add(&import->list, exports);
- }
- free(exports_list[j]);
- j++;
- }
- if(exports_list)
- free(exports_list);
- if(ret_msg)
- free(ret_msg);
-}
-
-#if 0
-static struct minios_list_head* probe_exports(void)
-{
- struct minios_list_head *exports;
- char **node_list = NULL, *msg = NULL;
- int i = 0;
-
- exports = xmalloc(struct minios_list_head);
- MINIOS_INIT_LIST_HEAD(exports);
-
- msg = xenbus_ls(XBT_NIL, "/local/domain", &node_list);
- if(msg)
- {
- printk("Could not list VFS exports (%s).\n", msg);
- goto exit;
- }
-
- while(node_list[i])
- {
- add_export(exports, atoi(node_list[i]));
- free(node_list[i]);
- i++;
- }
-
-exit:
- if(msg)
- free(msg);
- if(node_list)
- free(node_list);
- return exports;
-}
-#endif
-
-MINIOS_LIST_HEAD(exports);
-
-void init_fs_frontend(void)
-{
- struct minios_list_head *entry;
- struct fs_import *import = NULL;
- printk("Initing FS frontend(s).\n");
-
- add_export(&exports, 0);
- minios_list_for_each(entry, &exports)
- {
- import = minios_list_entry(entry, struct fs_import, list);
- printk("FS export [dom=%d, id=%d] found\n",
- import->dom_id, import->export_id);
- if (init_fs_import(import) != 0) {
- fs_import = import;
- break;
- }
- }
-
- if (!fs_import)
- printk("No FS import\n");
-}
-
-/* TODO: shutdown */
projects / people / liuw / libxenctrl-split / mini-os.git / commitdiff