Fix synchronicity for ZVOLs.

[zfs.git] / module / zfs / zvol.c

diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c
index 65a9240..0aaa268 100644 (file)
--- a/module/zfs/zvol.c
+++ b/module/zfs/zvol.c
@@ -228,7 +228,7 @@ zvol_check_volsize(uint64_t volsize, uint64_t blocksize)
  * Ensure the zap is flushed then inform the VFS of the capacity change.
  */
 static int
-zvol_update_volsize(zvol_state_t *zv, uint64_t volsize)
+zvol_update_volsize(zvol_state_t *zv, uint64_t volsize, objset_t *os)
 {
        struct block_device *bdev;
        dmu_tx_t *tx;
@@ -236,7 +236,7 @@ zvol_update_volsize(zvol_state_t *zv, uint64_t volsize)
 
        ASSERT(MUTEX_HELD(&zvol_state_lock));
 
-       tx = dmu_tx_create(zv->zv_objset);
+       tx = dmu_tx_create(os);
        dmu_tx_hold_zap(tx, ZVOL_ZAP_OBJ, TRUE, NULL);
        error = dmu_tx_assign(tx, TXG_WAIT);
        if (error) {
@@ -244,27 +244,35 @@ zvol_update_volsize(zvol_state_t *zv, uint64_t volsize)
                return (error);
        }
 
-       error = zap_update(zv->zv_objset, ZVOL_ZAP_OBJ, "size", 8, 1,
+       error = zap_update(os, ZVOL_ZAP_OBJ, "size", 8, 1,
            &volsize, tx);
        dmu_tx_commit(tx);
 
        if (error)
                return (error);
 
-       error = dmu_free_long_range(zv->zv_objset,
+       error = dmu_free_long_range(os,
            ZVOL_OBJ, volsize, DMU_OBJECT_END);
        if (error)
                return (error);
 
-       zv->zv_volsize = volsize;
-       zv->zv_changed = 1;
-
        bdev = bdget_disk(zv->zv_disk, 0);
        if (!bdev)
-               return EIO;
+               return (EIO);
+/*
+ * 2.6.28 API change
+ * Added check_disk_size_change() helper function.
+ */
+#ifdef HAVE_CHECK_DISK_SIZE_CHANGE
+       set_capacity(zv->zv_disk, volsize >> 9);
+       zv->zv_volsize = volsize;
+       check_disk_size_change(zv->zv_disk, bdev);
+#else
+       zv->zv_volsize = volsize;
+       zv->zv_changed = 1;
+       (void) check_disk_change(bdev);
+#endif /* HAVE_CHECK_DISK_SIZE_CHANGE */
 
-       error = check_disk_change(bdev);
-       ASSERT3U(error, !=, 0);
        bdput(bdev);
 
        return (0);
@@ -311,7 +319,7 @@ zvol_set_volsize(const char *name, uint64_t volsize)
                goto out_doi;
        }
 
-       error = zvol_update_volsize(zv, volsize);
+       error = zvol_update_volsize(zv, volsize, os);
 out_doi:
        kmem_free(doi, sizeof(dmu_object_info_t));
 out:
@@ -526,6 +534,17 @@ zvol_write(void *arg)
        dmu_tx_t *tx;
        rl_t *rl;
 
+       if (req->cmd_flags & VDEV_REQ_FLUSH)
+               zil_commit(zv->zv_zilog, ZVOL_OBJ);
+
+       /*
+        * Some requests are just for flush and nothing else.
+        */
+       if (size == 0) {
+               blk_end_request(req, 0, size);
+               return;
+       }
+
        rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER);
 
        tx = dmu_tx_create(zv->zv_objset);
@@ -542,12 +561,14 @@ zvol_write(void *arg)
 
        error = dmu_write_req(zv->zv_objset, ZVOL_OBJ, req, tx);
        if (error == 0)
-               zvol_log_write(zv, tx, offset, size, rq_is_sync(req));
+               zvol_log_write(zv, tx, offset, size,
+                   req->cmd_flags & VDEV_REQ_FUA);
 
        dmu_tx_commit(tx);
        zfs_range_unlock(rl);
 
-       if (rq_is_sync(req))
+       if ((req->cmd_flags & VDEV_REQ_FUA) ||
+           zv->zv_objset->os_sync == ZFS_SYNC_ALWAYS)
                zil_commit(zv->zv_zilog, ZVOL_OBJ);
 
        blk_end_request(req, -error, size);
@@ -570,6 +591,11 @@ zvol_read(void *arg)
        int error;
        rl_t *rl;
 
+       if (size == 0) {
+               blk_end_request(req, 0, size);
+               return;
+       }
+
        rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
 
        error = dmu_read_req(zv->zv_objset, ZVOL_OBJ, req);
@@ -619,7 +645,7 @@ zvol_request(struct request_queue *q)
        while ((req = blk_fetch_request(q)) != NULL) {
                size = blk_rq_bytes(req);
 
-               if (blk_rq_pos(req) + blk_rq_sectors(req) >
+               if (size != 0 && blk_rq_pos(req) + blk_rq_sectors(req) >
                    get_capacity(zv->zv_disk)) {
                        printk(KERN_INFO
                               "%s: bad access: block=%llu, count=%lu\n",
@@ -1054,6 +1080,12 @@ zvol_alloc(dev_t dev, const char *name)
        if (zv->zv_queue == NULL)
                goto out_kmem;
 
+#ifdef HAVE_BLK_QUEUE_FLUSH
+       blk_queue_flush(zv->zv_queue, VDEV_REQ_FLUSH | VDEV_REQ_FUA);
+#else
+       blk_queue_ordered(zv->zv_queue, QUEUE_ORDERED_DRAIN, NULL);
+#endif /* HAVE_BLK_QUEUE_FLUSH */
+
        zv->zv_disk = alloc_disk(ZVOL_MINORS);
        if (zv->zv_disk == NULL)
                goto out_queue;
@@ -1342,8 +1374,8 @@ zvol_fini(void)
        list_destroy(&zvol_state_list);
 }
 
-module_param(zvol_major, uint, 0);
+module_param(zvol_major, uint, 0444);
 MODULE_PARM_DESC(zvol_major, "Major number for zvol device");
 
-module_param(zvol_threads, uint, 0);
+module_param(zvol_threads, uint, 0444);
 MODULE_PARM_DESC(zvol_threads, "Number of threads for zvol device");