#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;
uint32_t blocksize = zv->zv_volblocksize;
zilog_t *zilog = zv->zv_zilog;
boolean_t slogging;
+ ssize_t immediate_write_sz;
if (zil_replaying(zilog, tx))
return;
- slogging = spa_has_slogs(zilog->zl_spa);
+ immediate_write_sz = (zilog->zl_logbias == ZFS_LOGBIAS_THROUGHPUT)
+ ? 0 : zvol_immediate_write_sz;
+ slogging = spa_has_slogs(zilog->zl_spa) &&
+ (zilog->zl_logbias == ZFS_LOGBIAS_LATENCY);
while (size) {
itx_t *itx;
* Unlike zfs_log_write() we can be called with
* up to DMU_MAX_ACCESS/2 (5MB) writes.
*/
- if (blocksize > zvol_immediate_write_sz && !slogging &&
+ if (blocksize > immediate_write_sz && !slogging &&
size >= blocksize && offset % blocksize == 0) {
write_state = WR_INDIRECT; /* uses dmu_sync */
len = blocksize;
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
int error;
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 (offset + size > zv->zv_volsize) {
blk_end_request(req, -EIO, size);
- return;
+ goto out;
}
if (size == 0) {
blk_end_request(req, 0, size);
- return;
+ goto out;
}
rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER);
zfs_range_unlock(rl);
blk_end_request(req, -error, size);
+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);
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
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));
{
int error;
- /*
- * The zvol taskqs are created with TASKQ_NORECLAIM so they may be
- * used safely as a swap device. If direct reclaim is allowed then
- * they quickly deadlock in one of the internal memory allocations.
- */
zvol_taskq = taskq_create(ZVOL_DRIVER, zvol_threads, maxclsyspri,
- zvol_threads, INT_MAX,
- TASKQ_PREPOPULATE | TASKQ_NORECLAIM);
+ zvol_threads, INT_MAX, TASKQ_PREPOPULATE);
if (zvol_taskq == NULL) {
printk(KERN_INFO "ZFS: taskq_create() failed\n");
return (-ENOMEM);
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");