diff options
| -rw-r--r-- | drivers/md/dm-ioctl.c | 11 | ||||
| -rw-r--r-- | drivers/md/dm.c | 92 | ||||
| -rw-r--r-- | drivers/md/dm.h | 2 |
3 files changed, 79 insertions, 26 deletions
diff --git a/drivers/md/dm-ioctl.c b/drivers/md/dm-ioctl.c index 4702f38..ed85859 100644 --- a/drivers/md/dm-ioctl.c +++ b/drivers/md/dm-ioctl.c @@ -1189,7 +1189,7 @@ static int table_load(struct dm_ioctl *param, size_t param_size) goto out; } - /* Protect md->type against concurrent table loads. */ + /* Protect md->type and md->queue against concurrent table loads. */ dm_lock_md_type(md); if (dm_get_md_type(md) == DM_TYPE_NONE) /* Initial table load: acquire type of table. */ @@ -1201,6 +1201,15 @@ static int table_load(struct dm_ioctl *param, size_t param_size) r = -EINVAL; goto out; } + + /* setup md->queue to reflect md's type (may block) */ + r = dm_setup_md_queue(md); + if (r) { + DMWARN("unable to set up device queue for new table."); + dm_table_destroy(t); + dm_unlock_md_type(md); + goto out; + } dm_unlock_md_type(md); /* stage inactive table */ diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 345e94c..5ae0a05 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -126,7 +126,7 @@ struct mapped_device { struct request_queue *queue; unsigned type; - /* Protect type against concurrent access. */ + /* Protect queue and type against concurrent access. */ struct mutex type_lock; struct gendisk *disk; @@ -1856,6 +1856,28 @@ static const struct block_device_operations dm_blk_dops; static void dm_wq_work(struct work_struct *work); static void dm_rq_barrier_work(struct work_struct *work); +static void dm_init_md_queue(struct mapped_device *md) +{ + /* + * Request-based dm devices cannot be stacked on top of bio-based dm + * devices. The type of this dm device has not been decided yet. + * The type is decided at the first table loading time. + * To prevent problematic device stacking, clear the queue flag + * for request stacking support until then. + * + * This queue is new, so no concurrency on the queue_flags. + */ + queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue); + + md->queue->queuedata = md; + md->queue->backing_dev_info.congested_fn = dm_any_congested; + md->queue->backing_dev_info.congested_data = md; + blk_queue_make_request(md->queue, dm_request); + blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); + md->queue->unplug_fn = dm_unplug_all; + blk_queue_merge_bvec(md->queue, dm_merge_bvec); +} + /* * Allocate and initialise a blank device with a given minor. */ @@ -1895,33 +1917,11 @@ static struct mapped_device *alloc_dev(int minor) INIT_LIST_HEAD(&md->uevent_list); spin_lock_init(&md->uevent_lock); - md->queue = blk_init_queue(dm_request_fn, NULL); + md->queue = blk_alloc_queue(GFP_KERNEL); if (!md->queue) goto bad_queue; - /* - * Request-based dm devices cannot be stacked on top of bio-based dm - * devices. The type of this dm device has not been decided yet, - * although we initialized the queue using blk_init_queue(). - * The type is decided at the first table loading time. - * To prevent problematic device stacking, clear the queue flag - * for request stacking support until then. - * - * This queue is new, so no concurrency on the queue_flags. - */ - queue_flag_clear_unlocked(QUEUE_FLAG_STACKABLE, md->queue); - md->saved_make_request_fn = md->queue->make_request_fn; - md->queue->queuedata = md; - md->queue->backing_dev_info.congested_fn = dm_any_congested; - md->queue->backing_dev_info.congested_data = md; - blk_queue_make_request(md->queue, dm_request); - blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY); - md->queue->unplug_fn = dm_unplug_all; - blk_queue_merge_bvec(md->queue, dm_merge_bvec); - blk_queue_softirq_done(md->queue, dm_softirq_done); - blk_queue_prep_rq(md->queue, dm_prep_fn); - blk_queue_lld_busy(md->queue, dm_lld_busy); - blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN_FLUSH); + dm_init_md_queue(md); md->disk = alloc_disk(1); if (!md->disk) @@ -2160,6 +2160,48 @@ unsigned dm_get_md_type(struct mapped_device *md) return md->type; } +/* + * Fully initialize a request-based queue (->elevator, ->request_fn, etc). + */ +static int dm_init_request_based_queue(struct mapped_device *md) +{ + struct request_queue *q = NULL; + + if (md->queue->elevator) + return 1; + + /* Fully initialize the queue */ + q = blk_init_allocated_queue(md->queue, dm_request_fn, NULL); + if (!q) + return 0; + + md->queue = q; + md->saved_make_request_fn = md->queue->make_request_fn; + dm_init_md_queue(md); + blk_queue_softirq_done(md->queue, dm_softirq_done); + blk_queue_prep_rq(md->queue, dm_prep_fn); + blk_queue_lld_busy(md->queue, dm_lld_busy); + blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN_FLUSH); + + elv_register_queue(md->queue); + + return 1; +} + +/* + * Setup the DM device's queue based on md's type + */ +int dm_setup_md_queue(struct mapped_device *md) +{ + if ((dm_get_md_type(md) == DM_TYPE_REQUEST_BASED) && + !dm_init_request_based_queue(md)) { + DMWARN("Cannot initialize queue for request-based mapped device"); + return -EINVAL; + } + + return 0; +} + static struct mapped_device *dm_find_md(dev_t dev) { struct mapped_device *md; diff --git a/drivers/md/dm.h b/drivers/md/dm.h index 1db7825..450fbd9 100644 --- a/drivers/md/dm.h +++ b/drivers/md/dm.h @@ -71,6 +71,8 @@ void dm_unlock_md_type(struct mapped_device *md); void dm_set_md_type(struct mapped_device *md, unsigned type); unsigned dm_get_md_type(struct mapped_device *md); +int dm_setup_md_queue(struct mapped_device *md); + /* * To check the return value from dm_table_find_target(). */ |