X-Git-Url: https://git.camperquake.de/gitweb.cgi?a=blobdiff_plain;f=module%2Fzfs%2Fzvol.c;h=60ff64ebe7b03dfa41e96de42e611ecf02da7986;hb=8630650a8d9cfba379a5b73bd95e903d577e0d8d;hp=19888ea96f6cee4fb922d716dc36a177539cd36d;hpb=dde9380a1bf9084d0c8a3e073cdd65bb81db1a23;p=zfs.git diff --git a/module/zfs/zvol.c b/module/zfs/zvol.c index 19888ea..60ff64e 100644 --- a/module/zfs/zvol.c +++ b/module/zfs/zvol.c @@ -46,8 +46,10 @@ #include #include +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; @@ -459,11 +461,15 @@ zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, 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; @@ -475,7 +481,7 @@ zvol_log_write(zvol_state_t *zv, dmu_tx_t *tx, * 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; @@ -534,6 +540,14 @@ zvol_write(void *arg) 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); @@ -542,7 +556,7 @@ zvol_write(void *arg) */ if (size == 0) { blk_end_request(req, 0, size); - return; + goto out; } rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER); @@ -556,7 +570,7 @@ zvol_write(void *arg) 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); @@ -572,7 +586,55 @@ zvol_write(void *arg) zil_commit(zv->zv_zilog, ZVOL_OBJ); blk_end_request(req, -error, size); +out: + current->flags &= ~PF_NOFS; +} + +#ifdef HAVE_BLK_QUEUE_DISCARD +static void +zvol_discard(void *arg) +{ + 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); + 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); + goto out; + } + + if (size == 0) { + blk_end_request(req, 0, size); + goto out; + } + + rl = zfs_range_lock(&zv->zv_znode, offset, size, RL_WRITER); + + error = dmu_free_long_range(zv->zv_objset, ZVOL_OBJ, offset, size); + + /* + * TODO: maybe we should add the operation to the log. + */ + + zfs_range_unlock(rl); + + blk_end_request(req, -error, size); +out: + current->flags &= ~PF_NOFS; } +#endif /* HAVE_BLK_QUEUE_DISCARD */ /* * Common read path running under the zvol taskq context. This function @@ -674,6 +736,13 @@ zvol_request(struct request_queue *q) break; } +#ifdef HAVE_BLK_QUEUE_DISCARD + if (req->cmd_flags & VDEV_REQ_DISCARD) { + zvol_dispatch(zvol_discard, req); + break; + } +#endif /* HAVE_BLK_QUEUE_DISCARD */ + zvol_dispatch(zvol_write, req); break; default: @@ -1193,6 +1262,12 @@ __zvol_create_minor(const char *name) blk_queue_max_segment_size(zv->zv_queue, UINT_MAX); 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, + (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 queue_flag_set_unlocked(QUEUE_FLAG_NONROT, zv->zv_queue); #endif @@ -1290,6 +1365,9 @@ zvol_create_minors(const char *pool) 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, @@ -1319,6 +1397,9 @@ zvol_remove_minors(const char *pool) 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)); @@ -1380,8 +1461,14 @@ zvol_fini(void) 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");