diff options
Diffstat (limited to 'drivers/md/dm.c')
| -rw-r--r-- | drivers/md/dm.c | 118 |
1 files changed, 111 insertions, 7 deletions
diff --git a/drivers/md/dm.c b/drivers/md/dm.c index 6a5e9ed2fcc3..0704c523a76b 100644 --- a/drivers/md/dm.c +++ b/drivers/md/dm.c @@ -49,6 +49,11 @@ static unsigned int _major = 0; static DEFINE_IDR(_minor_idr); static DEFINE_SPINLOCK(_minor_lock); + +static void do_deferred_remove(struct work_struct *w); + +static DECLARE_WORK(deferred_remove_work, do_deferred_remove); + /* * For bio-based dm. * One of these is allocated per bio. @@ -116,6 +121,7 @@ EXPORT_SYMBOL_GPL(dm_get_rq_mapinfo); #define DMF_DELETING 4 #define DMF_NOFLUSH_SUSPENDING 5 #define DMF_MERGE_IS_OPTIONAL 6 +#define DMF_DEFERRED_REMOVE 7 /* * A dummy definition to make RCU happy. @@ -211,10 +217,55 @@ struct dm_md_mempools { struct bio_set *bs; }; -#define MIN_IOS 256 +#define RESERVED_BIO_BASED_IOS 16 +#define RESERVED_REQUEST_BASED_IOS 256 +#define RESERVED_MAX_IOS 1024 static struct kmem_cache *_io_cache; static struct kmem_cache *_rq_tio_cache; +/* + * Bio-based DM's mempools' reserved IOs set by the user. + */ +static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; + +/* + * Request-based DM's mempools' reserved IOs set by the user. + */ +static unsigned reserved_rq_based_ios = RESERVED_REQUEST_BASED_IOS; + +static unsigned __dm_get_reserved_ios(unsigned *reserved_ios, + unsigned def, unsigned max) +{ + unsigned ios = ACCESS_ONCE(*reserved_ios); + unsigned modified_ios = 0; + + if (!ios) + modified_ios = def; + else if (ios > max) + modified_ios = max; + + if (modified_ios) { + (void)cmpxchg(reserved_ios, ios, modified_ios); + ios = modified_ios; + } + + return ios; +} + +unsigned dm_get_reserved_bio_based_ios(void) +{ + return __dm_get_reserved_ios(&reserved_bio_based_ios, + RESERVED_BIO_BASED_IOS, RESERVED_MAX_IOS); +} +EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); + +unsigned dm_get_reserved_rq_based_ios(void) +{ + return __dm_get_reserved_ios(&reserved_rq_based_ios, + RESERVED_REQUEST_BASED_IOS, RESERVED_MAX_IOS); +} +EXPORT_SYMBOL_GPL(dm_get_reserved_rq_based_ios); + static int __init local_init(void) { int r = -ENOMEM; @@ -254,6 +305,8 @@ out_free_io_cache: static void local_exit(void) { + flush_scheduled_work(); + kmem_cache_destroy(_rq_tio_cache); kmem_cache_destroy(_io_cache); unregister_blkdev(_major, _name); @@ -359,7 +412,10 @@ static void dm_blk_close(struct gendisk *disk, fmode_t mode) spin_lock(&_minor_lock); - atomic_dec(&md->open_count); + if (atomic_dec_and_test(&md->open_count) && + (test_bit(DMF_DEFERRED_REMOVE, &md->flags))) + schedule_work(&deferred_remove_work); + dm_put(md); spin_unlock(&_minor_lock); @@ -373,14 +429,18 @@ int dm_open_count(struct mapped_device *md) /* * Guarantees nothing is using the device before it's deleted. */ -int dm_lock_for_deletion(struct mapped_device *md) +int dm_lock_for_deletion(struct mapped_device *md, bool mark_deferred, bool only_deferred) { int r = 0; spin_lock(&_minor_lock); - if (dm_open_count(md)) + if (dm_open_count(md)) { r = -EBUSY; + if (mark_deferred) + set_bit(DMF_DEFERRED_REMOVE, &md->flags); + } else if (only_deferred && !test_bit(DMF_DEFERRED_REMOVE, &md->flags)) + r = -EEXIST; else set_bit(DMF_DELETING, &md->flags); @@ -389,6 +449,27 @@ int dm_lock_for_deletion(struct mapped_device *md) return r; } +int dm_cancel_deferred_remove(struct mapped_device *md) +{ + int r = 0; + + spin_lock(&_minor_lock); + + if (test_bit(DMF_DELETING, &md->flags)) + r = -EBUSY; + else + clear_bit(DMF_DEFERRED_REMOVE, &md->flags); + + spin_unlock(&_minor_lock); + + return r; +} + +static void do_deferred_remove(struct work_struct *w) +{ + dm_deferred_remove(); +} + sector_t dm_get_size(struct mapped_device *md) { return get_capacity(md->disk); @@ -2278,6 +2359,17 @@ struct target_type *dm_get_immutable_target_type(struct mapped_device *md) } /* + * The queue_limits are only valid as long as you have a reference + * count on 'md'. + */ +struct queue_limits *dm_get_queue_limits(struct mapped_device *md) +{ + BUG_ON(!atomic_read(&md->holders)); + return &md->queue->limits; +} +EXPORT_SYMBOL_GPL(dm_get_queue_limits); + +/* * Fully initialize a request-based queue (->elevator, ->request_fn, etc). */ static int dm_init_request_based_queue(struct mapped_device *md) @@ -2838,6 +2930,11 @@ int dm_suspended_md(struct mapped_device *md) return test_bit(DMF_SUSPENDED, &md->flags); } +int dm_test_deferred_remove_flag(struct mapped_device *md) +{ + return test_bit(DMF_DEFERRED_REMOVE, &md->flags); +} + int dm_suspended(struct dm_target *ti) { return dm_suspended_md(dm_table_get_md(ti->table)); @@ -2862,18 +2959,18 @@ struct dm_md_mempools *dm_alloc_md_mempools(unsigned type, unsigned integrity, u if (type == DM_TYPE_BIO_BASED) { cachep = _io_cache; - pool_size = 16; + pool_size = dm_get_reserved_bio_based_ios(); front_pad = roundup(per_bio_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone); } else if (type == DM_TYPE_REQUEST_BASED) { cachep = _rq_tio_cache; - pool_size = MIN_IOS; + pool_size = dm_get_reserved_rq_based_ios(); front_pad = offsetof(struct dm_rq_clone_bio_info, clone); /* per_bio_data_size is not used. See __bind_mempools(). */ WARN_ON(per_bio_data_size != 0); } else goto out; - pools->io_pool = mempool_create_slab_pool(MIN_IOS, cachep); + pools->io_pool = mempool_create_slab_pool(pool_size, cachep); if (!pools->io_pool) goto out; @@ -2924,6 +3021,13 @@ module_exit(dm_exit); module_param(major, uint, 0); MODULE_PARM_DESC(major, "The major number of the device mapper"); + +module_param(reserved_bio_based_ios, uint, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(reserved_bio_based_ios, "Reserved IOs in bio-based mempools"); + +module_param(reserved_rq_based_ios, uint, S_IRUGO | S_IWUSR); +MODULE_PARM_DESC(reserved_rq_based_ios, "Reserved IOs in request-based mempools"); + MODULE_DESCRIPTION(DM_NAME " driver"); MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); MODULE_LICENSE("GPL"); |