PR-1053: Demalloc the data path.

diff --git a/drivers/block-lcache.c b/drivers/block-lcache.c
index 0c92ac64c5365e6bb9022177336ccd5da1d55108..376811876725f7cc2a199ed6cdcd8c5f8670d8d5 100644 (file)
--- a/drivers/block-lcache.c
+++ b/drivers/block-lcache.c
@@ -72,6 +72,9 @@ struct local_cache {
        local_cache_request_t           requests[LOCAL_CACHE_REQUESTS];
        local_cache_request_t          *request_free_list[LOCAL_CACHE_REQUESTS];
        int                             requests_free;
+
+       char                           *buf;
+       size_t                          bufsz;
 };
 
 static void local_cache_complete_req(td_request_t, int);
@@ -88,39 +91,66 @@ local_cache_get_request(local_cache_t *cache)
 static inline void
 local_cache_put_request(local_cache_t *cache, local_cache_request_t *lreq)
 {
-       free(lreq->buf);
-       memset(lreq, 0, sizeof(local_cache_request_t));
        cache->request_free_list[cache->requests_free++] = lreq;
 }
 
 static int
-local_cache_open(td_driver_t *driver, const char *name, td_flag_t flags)
+local_cache_close(td_driver_t *driver)
 {
-       int i, err; 
-       local_cache_t *cache;
+       local_cache_t *cache = driver->data;
 
-       cache = (local_cache_t *)driver->data;
-       err   = tapdisk_namedup(&cache->name, (char *)name);
-       if (err)
-               return -ENOMEM;
-       cache->requests_free = LOCAL_CACHE_REQUESTS;
-       for (i = 0; i < LOCAL_CACHE_REQUESTS; i++)
-               cache->request_free_list[i] = cache->requests + i;
+       DPRINTF("Closing local cache for %s\n", cache->name);
 
-       DPRINTF("Opening local cache for %s\n", cache->name);
+       if (cache->buf)
+               munmap(cache->buf, cache->bufsz);
+
+       free(cache->name);
        return 0;
 }
 
 static int
-local_cache_close(td_driver_t *driver)
+local_cache_open(td_driver_t *driver, const char *name, td_flag_t flags)
 {
-       local_cache_t *cache;
+       local_cache_t *cache = driver->data;
+       int i, err;
+       int prot, _flags;
+       size_t lreq_bufsz;
 
-       cache = (local_cache_t *)driver->data;
-       DPRINTF("Closing local cache for %s\n", cache->name);
+       err   = tapdisk_namedup(&cache->name, (char *)name);
+       if (err)
+               goto fail;
+
+       lreq_bufsz   = BLKIF_MAX_SEGMENTS_PER_REQUEST * sysconf(_SC_PAGE_SIZE);
+       cache->bufsz = LOCAL_CACHE_REQUESTS * lreq_bufsz;
+
+       prot   = PROT_READ|PROT_WRITE;
+       _flags = MAP_ANONYMOUS|MAP_PRIVATE;
+       cache->buf = mmap(NULL, cache->bufsz, prot, _flags, -1, 0);
+       if (cache->buf == MAP_FAILED) {
+               cache->buf == NULL;
+               err = -errno;
+               goto fail;
+       }
 
-       free(cache->name);
+       err = mlock(cache->buf, cache->bufsz);
+       if (err) {
+               err = -errno;
+               goto fail;
+       }
+
+       cache->requests_free = LOCAL_CACHE_REQUESTS;
+       for (i = 0; i < LOCAL_CACHE_REQUESTS; i++) {
+               local_cache_request_t *lreq = &cache->requests[i];
+               lreq->buf = cache->buf + i * lreq_bufsz;
+               cache->request_free_list[i] = lreq;
+       }
+
+       DPRINTF("Opening local cache for %s\n", cache->name);
        return 0;
+
+fail:
+       local_cache_close(driver);
+       return err;
 }
 
 static void
@@ -197,43 +227,30 @@ local_cache_complete_req(td_request_t treq, int err)
 static void
 local_cache_queue_read(td_driver_t *driver, td_request_t treq)
 {
+       local_cache_t *cache = driver->data;
        int err;
-       char *buf;
        size_t size;
        td_request_t clone;
        local_cache_request_t *lreq;
-       local_cache_t *cache;
 
        //DPRINTF("LocalCache: read request! %lld (%d secs)\n", treq.sec, 
        //treq.secs);
 
-       cache = (local_cache_t *)driver->data;
-
-       clone = treq;
-       size  = treq.secs << VHD_SECTOR_SHIFT;
-
        lreq = local_cache_get_request(cache);
        if (!lreq) {
-               //EPRINTF("FAILED TO get lreq! %lld\n", treq.sec);
-               goto out;
-       }
-
-       err = posix_memalign((void **)&buf, 4096, size);
-       if (err) {
-               EPRINTF("FAILED TO posix_memalign! %d\n", err);
-               local_cache_put_request(cache, lreq);
-               goto out;
+               td_forward_request(treq);
+               return;
        }
 
        lreq->treq    = treq;
        lreq->cache   = cache;
-       lreq->buf     = buf;
 
        lreq->phase   = LC_READ;
        lreq->secs    = lreq->treq.secs;
        lreq->err     = 0;
 
-       clone.buf     = buf;
+       clone         = treq;
+       clone.buf     = lreq->buf;
        clone.cb      = local_cache_complete_req;
        clone.cb_data = lreq;