#include <sys/zvol.h>
#include <linux/blkdev_compat.h>
+unsigned int zvol_inhibit_dev = 0;
unsigned int zvol_major = ZVOL_MAJOR;
unsigned int zvol_threads = 32;
+unsigned long zvol_max_discard_blocks = 16384;
static taskq_t *zvol_taskq;
static kmutex_t zvol_state_lock;
dmu_tx_t *tx;
rl_t *rl;
+ /*
+ * Annotate this call path with a flag that indicates that it is
+ * unsafe to use KM_SLEEP during memory allocations due to the
+ * potential for a deadlock. KM_PUSHPAGE should be used instead.
+ */
+ ASSERT(!(current->flags & PF_NOFS));
+ current->flags |= PF_NOFS;
+
if (req->cmd_flags & VDEV_REQ_FLUSH)
zil_commit(zv->zv_zilog, ZVOL_OBJ);
*/
if (size == 0) {
blk_end_request(req, 0, size);
- return;
+ goto out;
}
rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER);
dmu_tx_abort(tx);
zfs_range_unlock(rl);
blk_end_request(req, -error, size);
- return;
+ goto out;
}
error = dmu_write_req(zv->zv_objset, ZVOL_OBJ, req, tx);
zil_commit(zv->zv_zilog, ZVOL_OBJ);
blk_end_request(req, -error, size);
+out:
+ current->flags &= ~PF_NOFS;
}
#ifdef HAVE_BLK_QUEUE_DISCARD
struct request *req = (struct request *)arg;
struct request_queue *q = req->q;
zvol_state_t *zv = q->queuedata;
- uint64_t offset = blk_rq_pos(req) << 9;
- uint64_t size = blk_rq_bytes(req);
+ uint64_t start = blk_rq_pos(req) << 9;
+ uint64_t end = start + blk_rq_bytes(req);
int error;
rl_t *rl;
- if (offset + size > zv->zv_volsize) {
- blk_end_request(req, -EIO, size);
- return;
+ /*
+ * Annotate this call path with a flag that indicates that it is
+ * unsafe to use KM_SLEEP during memory allocations due to the
+ * potential for a deadlock. KM_PUSHPAGE should be used instead.
+ */
+ ASSERT(!(current->flags & PF_NOFS));
+ current->flags |= PF_NOFS;
+
+ if (end > zv->zv_volsize) {
+ blk_end_request(req, -EIO, blk_rq_bytes(req));
+ goto out;
}
- if (size == 0) {
- blk_end_request(req, 0, size);
- return;
+ /*
+ * Align the request to volume block boundaries. If we don't,
+ * then this will force dnode_free_range() to zero out the
+ * unaligned parts, which is slow (read-modify-write) and
+ * useless since we are not freeing any space by doing so.
+ */
+ start = P2ROUNDUP(start, zv->zv_volblocksize);
+ end = P2ALIGN(end, zv->zv_volblocksize);
+
+ if (start >= end) {
+ blk_end_request(req, 0, blk_rq_bytes(req));
+ goto out;
}
- rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER);
+ rl = zfs_range_lock(&zv->zv_znode, start, end - start, RL_WRITER);
- error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, size);
+ error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, start, end - start);
/*
* TODO: maybe we should add the operation to the log.
zfs_range_unlock(rl);
- blk_end_request(req, -error, size);
+ blk_end_request(req, -error, blk_rq_bytes(req));
+out:
+ current->flags &= ~PF_NOFS;
}
#endif /* HAVE_BLK_QUEUE_DISCARD */
ASSERT(zio != NULL);
ASSERT(size != 0);
- zgd = (zgd_t *)kmem_zalloc(sizeof (zgd_t), KM_SLEEP);
+ zgd = (zgd_t *)kmem_zalloc(sizeof (zgd_t), KM_PUSHPAGE);
zgd->zgd_zilog = zv->zv_zilog;
zgd->zgd_rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_READER);
{
zil_close(zv->zv_zilog);
zv->zv_zilog = NULL;
+
dmu_buf_rele(zv->zv_dbuf, zvol_tag);
zv->zv_dbuf = NULL;
+
+ /*
+ * Evict cached data
+ */
+ if (dsl_dataset_is_dirty(dmu_objset_ds(zv->zv_objset)) &&
+ !(zv->zv_flags & ZVOL_RDONLY))
+ txg_wait_synced(dmu_objset_pool(zv->zv_objset), 0);
+ (void) dmu_objset_evict_dbufs(zv->zv_objset);
+
dmu_objset_disown(zv->zv_objset, zvol_tag);
zv->zv_objset = NULL;
}
mutex_enter(&zvol_state_lock);
zv = zvol_find_by_dev(dev);
- kobj = zv ? get_disk(zv->zv_disk) : ERR_PTR(-ENOENT);
+ kobj = zv ? get_disk(zv->zv_disk) : NULL;
mutex_exit(&zvol_state_lock);
return kobj;
zvol_alloc(dev_t dev, const char *name)
{
zvol_state_t *zv;
+ int error = 0;
zv = kmem_zalloc(sizeof (zvol_state_t), KM_SLEEP);
if (zv == NULL)
if (zv->zv_queue == NULL)
goto out_kmem;
+#ifdef HAVE_ELEVATOR_CHANGE
+ error = elevator_change(zv->zv_queue, "noop");
+#endif /* HAVE_ELEVATOR_CHANGE */
+ if (error) {
+ printk("ZFS: Unable to set \"%s\" scheduler for zvol %s: %d\n",
+ "noop", name, error);
+ goto out_queue;
+ }
+
#ifdef HAVE_BLK_QUEUE_FLUSH
blk_queue_flush(zv->zv_queue, VDEV_REQ_FLUSH | VDEV_REQ_FUA);
#else
blk_queue_physical_block_size(zv->zv_queue, zv->zv_volblocksize);
blk_queue_io_opt(zv->zv_queue, zv->zv_volblocksize);
#ifdef HAVE_BLK_QUEUE_DISCARD
- blk_queue_max_discard_sectors(zv->zv_queue, UINT_MAX);
+ blk_queue_max_discard_sectors(zv->zv_queue,
+ (zvol_max_discard_blocks * zv->zv_volblocksize) >> 9);
+ blk_queue_discard_granularity(zv->zv_queue, zv->zv_volblocksize);
queue_flag_set_unlocked(QUEUE_FLAG_DISCARD, zv->zv_queue);
#endif
#ifdef HAVE_BLK_QUEUE_NONROT
else
zil_replay(os, zv, zvol_replay_vector);
+ zv->zv_objset = NULL;
out_dmu_objset_disown:
dmu_objset_disown(os, zvol_tag);
- zv->zv_objset = NULL;
out_doi:
kmem_free(doi, sizeof(dmu_object_info_t));
out:
spa_t *spa = NULL;
int error = 0;
+ if (zvol_inhibit_dev)
+ return (0);
+
mutex_enter(&zvol_state_lock);
if (pool) {
error = dmu_objset_find_spa(NULL, pool, zvol_create_minors_cb,
zvol_state_t *zv, *zv_next;
char *str;
+ if (zvol_inhibit_dev)
+ return;
+
str = kmem_zalloc(MAXNAMELEN, KM_SLEEP);
if (pool) {
(void) strncpy(str, pool, strlen(pool));
list_destroy(&zvol_state_list);
}
+module_param(zvol_inhibit_dev, uint, 0644);
+MODULE_PARM_DESC(zvol_inhibit_dev, "Do not create zvol device nodes");
+
module_param(zvol_major, uint, 0444);
MODULE_PARM_DESC(zvol_major, "Major number for zvol device");
module_param(zvol_threads, uint, 0444);
MODULE_PARM_DESC(zvol_threads, "Number of threads for zvol device");
+
+module_param(zvol_max_discard_blocks, ulong, 0444);
+MODULE_PARM_DESC(zvol_max_discard_blocks, "Max number of blocks to discard at once");
git://git.camperquake.de / zfs.git / blobdiff