| /* |
| * Copyright (C) 2001, 2002 Sistina Software (UK) Limited. |
| * Copyright (C) 2004-2008 Red Hat, Inc. All rights reserved. |
| * |
| * This file is released under the GPL. |
| */ |
| |
| #include "dm-core.h" |
| #include "dm-rq.h" |
| #include "dm-uevent.h" |
| |
| #include <linux/init.h> |
| #include <linux/module.h> |
| #include <linux/mutex.h> |
| #include <linux/sched/signal.h> |
| #include <linux/blkpg.h> |
| #include <linux/bio.h> |
| #include <linux/mempool.h> |
| #include <linux/dax.h> |
| #include <linux/slab.h> |
| #include <linux/idr.h> |
| #include <linux/uio.h> |
| #include <linux/hdreg.h> |
| #include <linux/delay.h> |
| #include <linux/wait.h> |
| #include <linux/pr.h> |
| #include <linux/refcount.h> |
| |
| #define DM_MSG_PREFIX "core" |
| |
| /* |
| * Cookies are numeric values sent with CHANGE and REMOVE |
| * uevents while resuming, removing or renaming the device. |
| */ |
| #define DM_COOKIE_ENV_VAR_NAME "DM_COOKIE" |
| #define DM_COOKIE_LENGTH 24 |
| |
| static const char *_name = DM_NAME; |
| |
| static unsigned int major = 0; |
| 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); |
| |
| static struct workqueue_struct *deferred_remove_workqueue; |
| |
| atomic_t dm_global_event_nr = ATOMIC_INIT(0); |
| DECLARE_WAIT_QUEUE_HEAD(dm_global_eventq); |
| |
| void dm_issue_global_event(void) |
| { |
| atomic_inc(&dm_global_event_nr); |
| wake_up(&dm_global_eventq); |
| } |
| |
| /* |
| * One of these is allocated (on-stack) per original bio. |
| */ |
| struct clone_info { |
| struct dm_table *map; |
| struct bio *bio; |
| struct dm_io *io; |
| sector_t sector; |
| unsigned sector_count; |
| }; |
| |
| /* |
| * One of these is allocated per clone bio. |
| */ |
| #define DM_TIO_MAGIC 7282014 |
| struct dm_target_io { |
| unsigned magic; |
| struct dm_io *io; |
| struct dm_target *ti; |
| unsigned target_bio_nr; |
| unsigned *len_ptr; |
| bool inside_dm_io; |
| struct bio clone; |
| }; |
| |
| /* |
| * One of these is allocated per original bio. |
| * It contains the first clone used for that original. |
| */ |
| #define DM_IO_MAGIC 5191977 |
| struct dm_io { |
| unsigned magic; |
| struct mapped_device *md; |
| blk_status_t status; |
| atomic_t io_count; |
| struct bio *orig_bio; |
| unsigned long start_time; |
| spinlock_t endio_lock; |
| struct dm_stats_aux stats_aux; |
| /* last member of dm_target_io is 'struct bio' */ |
| struct dm_target_io tio; |
| }; |
| |
| void *dm_per_bio_data(struct bio *bio, size_t data_size) |
| { |
| struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
| if (!tio->inside_dm_io) |
| return (char *)bio - offsetof(struct dm_target_io, clone) - data_size; |
| return (char *)bio - offsetof(struct dm_target_io, clone) - offsetof(struct dm_io, tio) - data_size; |
| } |
| EXPORT_SYMBOL_GPL(dm_per_bio_data); |
| |
| struct bio *dm_bio_from_per_bio_data(void *data, size_t data_size) |
| { |
| struct dm_io *io = (struct dm_io *)((char *)data + data_size); |
| if (io->magic == DM_IO_MAGIC) |
| return (struct bio *)((char *)io + offsetof(struct dm_io, tio) + offsetof(struct dm_target_io, clone)); |
| BUG_ON(io->magic != DM_TIO_MAGIC); |
| return (struct bio *)((char *)io + offsetof(struct dm_target_io, clone)); |
| } |
| EXPORT_SYMBOL_GPL(dm_bio_from_per_bio_data); |
| |
| unsigned dm_bio_get_target_bio_nr(const struct bio *bio) |
| { |
| return container_of(bio, struct dm_target_io, clone)->target_bio_nr; |
| } |
| EXPORT_SYMBOL_GPL(dm_bio_get_target_bio_nr); |
| |
| #define MINOR_ALLOCED ((void *)-1) |
| |
| /* |
| * Bits for the md->flags field. |
| */ |
| #define DMF_BLOCK_IO_FOR_SUSPEND 0 |
| #define DMF_SUSPENDED 1 |
| #define DMF_FROZEN 2 |
| #define DMF_FREEING 3 |
| #define DMF_DELETING 4 |
| #define DMF_NOFLUSH_SUSPENDING 5 |
| #define DMF_DEFERRED_REMOVE 6 |
| #define DMF_SUSPENDED_INTERNALLY 7 |
| |
| #define DM_NUMA_NODE NUMA_NO_NODE |
| static int dm_numa_node = DM_NUMA_NODE; |
| |
| /* |
| * For mempools pre-allocation at the table loading time. |
| */ |
| struct dm_md_mempools { |
| struct bio_set bs; |
| struct bio_set io_bs; |
| }; |
| |
| struct table_device { |
| struct list_head list; |
| refcount_t count; |
| struct dm_dev dm_dev; |
| }; |
| |
| static struct kmem_cache *_rq_tio_cache; |
| static struct kmem_cache *_rq_cache; |
| |
| /* |
| * Bio-based DM's mempools' reserved IOs set by the user. |
| */ |
| #define RESERVED_BIO_BASED_IOS 16 |
| static unsigned reserved_bio_based_ios = RESERVED_BIO_BASED_IOS; |
| |
| static int __dm_get_module_param_int(int *module_param, int min, int max) |
| { |
| int param = READ_ONCE(*module_param); |
| int modified_param = 0; |
| bool modified = true; |
| |
| if (param < min) |
| modified_param = min; |
| else if (param > max) |
| modified_param = max; |
| else |
| modified = false; |
| |
| if (modified) { |
| (void)cmpxchg(module_param, param, modified_param); |
| param = modified_param; |
| } |
| |
| return param; |
| } |
| |
| unsigned __dm_get_module_param(unsigned *module_param, |
| unsigned def, unsigned max) |
| { |
| unsigned param = READ_ONCE(*module_param); |
| unsigned modified_param = 0; |
| |
| if (!param) |
| modified_param = def; |
| else if (param > max) |
| modified_param = max; |
| |
| if (modified_param) { |
| (void)cmpxchg(module_param, param, modified_param); |
| param = modified_param; |
| } |
| |
| return param; |
| } |
| |
| unsigned dm_get_reserved_bio_based_ios(void) |
| { |
| return __dm_get_module_param(&reserved_bio_based_ios, |
| RESERVED_BIO_BASED_IOS, DM_RESERVED_MAX_IOS); |
| } |
| EXPORT_SYMBOL_GPL(dm_get_reserved_bio_based_ios); |
| |
| static unsigned dm_get_numa_node(void) |
| { |
| return __dm_get_module_param_int(&dm_numa_node, |
| DM_NUMA_NODE, num_online_nodes() - 1); |
| } |
| |
| static int __init local_init(void) |
| { |
| int r = -ENOMEM; |
| |
| _rq_tio_cache = KMEM_CACHE(dm_rq_target_io, 0); |
| if (!_rq_tio_cache) |
| return r; |
| |
| _rq_cache = kmem_cache_create("dm_old_clone_request", sizeof(struct request), |
| __alignof__(struct request), 0, NULL); |
| if (!_rq_cache) |
| goto out_free_rq_tio_cache; |
| |
| r = dm_uevent_init(); |
| if (r) |
| goto out_free_rq_cache; |
| |
| deferred_remove_workqueue = alloc_workqueue("kdmremove", WQ_UNBOUND, 1); |
| if (!deferred_remove_workqueue) { |
| r = -ENOMEM; |
| goto out_uevent_exit; |
| } |
| |
| _major = major; |
| r = register_blkdev(_major, _name); |
| if (r < 0) |
| goto out_free_workqueue; |
| |
| if (!_major) |
| _major = r; |
| |
| return 0; |
| |
| out_free_workqueue: |
| destroy_workqueue(deferred_remove_workqueue); |
| out_uevent_exit: |
| dm_uevent_exit(); |
| out_free_rq_cache: |
| kmem_cache_destroy(_rq_cache); |
| out_free_rq_tio_cache: |
| kmem_cache_destroy(_rq_tio_cache); |
| |
| return r; |
| } |
| |
| static void local_exit(void) |
| { |
| flush_scheduled_work(); |
| destroy_workqueue(deferred_remove_workqueue); |
| |
| kmem_cache_destroy(_rq_cache); |
| kmem_cache_destroy(_rq_tio_cache); |
| unregister_blkdev(_major, _name); |
| dm_uevent_exit(); |
| |
| _major = 0; |
| |
| DMINFO("cleaned up"); |
| } |
| |
| static int (*_inits[])(void) __initdata = { |
| local_init, |
| dm_target_init, |
| dm_linear_init, |
| dm_stripe_init, |
| dm_io_init, |
| dm_kcopyd_init, |
| dm_interface_init, |
| dm_statistics_init, |
| }; |
| |
| static void (*_exits[])(void) = { |
| local_exit, |
| dm_target_exit, |
| dm_linear_exit, |
| dm_stripe_exit, |
| dm_io_exit, |
| dm_kcopyd_exit, |
| dm_interface_exit, |
| dm_statistics_exit, |
| }; |
| |
| static int __init dm_init(void) |
| { |
| const int count = ARRAY_SIZE(_inits); |
| |
| int r, i; |
| |
| for (i = 0; i < count; i++) { |
| r = _inits[i](); |
| if (r) |
| goto bad; |
| } |
| |
| return 0; |
| |
| bad: |
| while (i--) |
| _exits[i](); |
| |
| return r; |
| } |
| |
| static void __exit dm_exit(void) |
| { |
| int i = ARRAY_SIZE(_exits); |
| |
| while (i--) |
| _exits[i](); |
| |
| /* |
| * Should be empty by this point. |
| */ |
| idr_destroy(&_minor_idr); |
| } |
| |
| /* |
| * Block device functions |
| */ |
| int dm_deleting_md(struct mapped_device *md) |
| { |
| return test_bit(DMF_DELETING, &md->flags); |
| } |
| |
| static int dm_blk_open(struct block_device *bdev, fmode_t mode) |
| { |
| struct mapped_device *md; |
| |
| spin_lock(&_minor_lock); |
| |
| md = bdev->bd_disk->private_data; |
| if (!md) |
| goto out; |
| |
| if (test_bit(DMF_FREEING, &md->flags) || |
| dm_deleting_md(md)) { |
| md = NULL; |
| goto out; |
| } |
| |
| dm_get(md); |
| atomic_inc(&md->open_count); |
| out: |
| spin_unlock(&_minor_lock); |
| |
| return md ? 0 : -ENXIO; |
| } |
| |
| static void dm_blk_close(struct gendisk *disk, fmode_t mode) |
| { |
| struct mapped_device *md; |
| |
| spin_lock(&_minor_lock); |
| |
| md = disk->private_data; |
| if (WARN_ON(!md)) |
| goto out; |
| |
| if (atomic_dec_and_test(&md->open_count) && |
| (test_bit(DMF_DEFERRED_REMOVE, &md->flags))) |
| queue_work(deferred_remove_workqueue, &deferred_remove_work); |
| |
| dm_put(md); |
| out: |
| spin_unlock(&_minor_lock); |
| } |
| |
| int dm_open_count(struct mapped_device *md) |
| { |
| return atomic_read(&md->open_count); |
| } |
| |
| /* |
| * Guarantees nothing is using the device before it's deleted. |
| */ |
| 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)) { |
| 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); |
| |
| spin_unlock(&_minor_lock); |
| |
| 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); |
| } |
| |
| struct request_queue *dm_get_md_queue(struct mapped_device *md) |
| { |
| return md->queue; |
| } |
| |
| struct dm_stats *dm_get_stats(struct mapped_device *md) |
| { |
| return &md->stats; |
| } |
| |
| static int dm_blk_getgeo(struct block_device *bdev, struct hd_geometry *geo) |
| { |
| struct mapped_device *md = bdev->bd_disk->private_data; |
| |
| return dm_get_geometry(md, geo); |
| } |
| |
| static int dm_prepare_ioctl(struct mapped_device *md, int *srcu_idx, |
| struct block_device **bdev) |
| __acquires(md->io_barrier) |
| { |
| struct dm_target *tgt; |
| struct dm_table *map; |
| int r; |
| |
| retry: |
| r = -ENOTTY; |
| map = dm_get_live_table(md, srcu_idx); |
| if (!map || !dm_table_get_size(map)) |
| return r; |
| |
| /* We only support devices that have a single target */ |
| if (dm_table_get_num_targets(map) != 1) |
| return r; |
| |
| tgt = dm_table_get_target(map, 0); |
| if (!tgt->type->prepare_ioctl) |
| return r; |
| |
| if (dm_suspended_md(md)) |
| return -EAGAIN; |
| |
| r = tgt->type->prepare_ioctl(tgt, bdev); |
| if (r == -ENOTCONN && !fatal_signal_pending(current)) { |
| dm_put_live_table(md, *srcu_idx); |
| msleep(10); |
| goto retry; |
| } |
| |
| return r; |
| } |
| |
| static void dm_unprepare_ioctl(struct mapped_device *md, int srcu_idx) |
| __releases(md->io_barrier) |
| { |
| dm_put_live_table(md, srcu_idx); |
| } |
| |
| static int dm_blk_ioctl(struct block_device *bdev, fmode_t mode, |
| unsigned int cmd, unsigned long arg) |
| { |
| struct mapped_device *md = bdev->bd_disk->private_data; |
| int r, srcu_idx; |
| |
| r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
| if (r < 0) |
| goto out; |
| |
| if (r > 0) { |
| /* |
| * Target determined this ioctl is being issued against a |
| * subset of the parent bdev; require extra privileges. |
| */ |
| if (!capable(CAP_SYS_RAWIO)) { |
| DMWARN_LIMIT( |
| "%s: sending ioctl %x to DM device without required privilege.", |
| current->comm, cmd); |
| r = -ENOIOCTLCMD; |
| goto out; |
| } |
| } |
| |
| r = __blkdev_driver_ioctl(bdev, mode, cmd, arg); |
| out: |
| dm_unprepare_ioctl(md, srcu_idx); |
| return r; |
| } |
| |
| static void start_io_acct(struct dm_io *io); |
| |
| static struct dm_io *alloc_io(struct mapped_device *md, struct bio *bio) |
| { |
| struct dm_io *io; |
| struct dm_target_io *tio; |
| struct bio *clone; |
| |
| clone = bio_alloc_bioset(GFP_NOIO, 0, &md->io_bs); |
| if (!clone) |
| return NULL; |
| |
| tio = container_of(clone, struct dm_target_io, clone); |
| tio->inside_dm_io = true; |
| tio->io = NULL; |
| |
| io = container_of(tio, struct dm_io, tio); |
| io->magic = DM_IO_MAGIC; |
| io->status = 0; |
| atomic_set(&io->io_count, 1); |
| io->orig_bio = bio; |
| io->md = md; |
| spin_lock_init(&io->endio_lock); |
| |
| start_io_acct(io); |
| |
| return io; |
| } |
| |
| static void free_io(struct mapped_device *md, struct dm_io *io) |
| { |
| bio_put(&io->tio.clone); |
| } |
| |
| static struct dm_target_io *alloc_tio(struct clone_info *ci, struct dm_target *ti, |
| unsigned target_bio_nr, gfp_t gfp_mask) |
| { |
| struct dm_target_io *tio; |
| |
| if (!ci->io->tio.io) { |
| /* the dm_target_io embedded in ci->io is available */ |
| tio = &ci->io->tio; |
| } else { |
| struct bio *clone = bio_alloc_bioset(gfp_mask, 0, &ci->io->md->bs); |
| if (!clone) |
| return NULL; |
| |
| tio = container_of(clone, struct dm_target_io, clone); |
| tio->inside_dm_io = false; |
| } |
| |
| tio->magic = DM_TIO_MAGIC; |
| tio->io = ci->io; |
| tio->ti = ti; |
| tio->target_bio_nr = target_bio_nr; |
| |
| return tio; |
| } |
| |
| static void free_tio(struct dm_target_io *tio) |
| { |
| if (tio->inside_dm_io) |
| return; |
| bio_put(&tio->clone); |
| } |
| |
| int md_in_flight(struct mapped_device *md) |
| { |
| return atomic_read(&md->pending[READ]) + |
| atomic_read(&md->pending[WRITE]); |
| } |
| |
| static void start_io_acct(struct dm_io *io) |
| { |
| struct mapped_device *md = io->md; |
| struct bio *bio = io->orig_bio; |
| int rw = bio_data_dir(bio); |
| |
| io->start_time = jiffies; |
| |
| generic_start_io_acct(md->queue, rw, bio_sectors(bio), &dm_disk(md)->part0); |
| |
| atomic_set(&dm_disk(md)->part0.in_flight[rw], |
| atomic_inc_return(&md->pending[rw])); |
| |
| if (unlikely(dm_stats_used(&md->stats))) |
| dm_stats_account_io(&md->stats, bio_data_dir(bio), |
| bio->bi_iter.bi_sector, bio_sectors(bio), |
| false, 0, &io->stats_aux); |
| } |
| |
| static void end_io_acct(struct dm_io *io) |
| { |
| struct mapped_device *md = io->md; |
| struct bio *bio = io->orig_bio; |
| unsigned long duration = jiffies - io->start_time; |
| int pending; |
| int rw = bio_data_dir(bio); |
| |
| generic_end_io_acct(md->queue, rw, &dm_disk(md)->part0, io->start_time); |
| |
| if (unlikely(dm_stats_used(&md->stats))) |
| dm_stats_account_io(&md->stats, bio_data_dir(bio), |
| bio->bi_iter.bi_sector, bio_sectors(bio), |
| true, duration, &io->stats_aux); |
| |
| /* |
| * After this is decremented the bio must not be touched if it is |
| * a flush. |
| */ |
| pending = atomic_dec_return(&md->pending[rw]); |
| atomic_set(&dm_disk(md)->part0.in_flight[rw], pending); |
| pending += atomic_read(&md->pending[rw^0x1]); |
| |
| /* nudge anyone waiting on suspend queue */ |
| if (!pending) |
| wake_up(&md->wait); |
| } |
| |
| /* |
| * Add the bio to the list of deferred io. |
| */ |
| static void queue_io(struct mapped_device *md, struct bio *bio) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&md->deferred_lock, flags); |
| bio_list_add(&md->deferred, bio); |
| spin_unlock_irqrestore(&md->deferred_lock, flags); |
| queue_work(md->wq, &md->work); |
| } |
| |
| /* |
| * Everyone (including functions in this file), should use this |
| * function to access the md->map field, and make sure they call |
| * dm_put_live_table() when finished. |
| */ |
| struct dm_table *dm_get_live_table(struct mapped_device *md, int *srcu_idx) __acquires(md->io_barrier) |
| { |
| *srcu_idx = srcu_read_lock(&md->io_barrier); |
| |
| return srcu_dereference(md->map, &md->io_barrier); |
| } |
| |
| void dm_put_live_table(struct mapped_device *md, int srcu_idx) __releases(md->io_barrier) |
| { |
| srcu_read_unlock(&md->io_barrier, srcu_idx); |
| } |
| |
| void dm_sync_table(struct mapped_device *md) |
| { |
| synchronize_srcu(&md->io_barrier); |
| synchronize_rcu_expedited(); |
| } |
| |
| /* |
| * A fast alternative to dm_get_live_table/dm_put_live_table. |
| * The caller must not block between these two functions. |
| */ |
| static struct dm_table *dm_get_live_table_fast(struct mapped_device *md) __acquires(RCU) |
| { |
| rcu_read_lock(); |
| return rcu_dereference(md->map); |
| } |
| |
| static void dm_put_live_table_fast(struct mapped_device *md) __releases(RCU) |
| { |
| rcu_read_unlock(); |
| } |
| |
| static char *_dm_claim_ptr = "I belong to device-mapper"; |
| |
| /* |
| * Open a table device so we can use it as a map destination. |
| */ |
| static int open_table_device(struct table_device *td, dev_t dev, |
| struct mapped_device *md) |
| { |
| struct block_device *bdev; |
| |
| int r; |
| |
| BUG_ON(td->dm_dev.bdev); |
| |
| bdev = blkdev_get_by_dev(dev, td->dm_dev.mode | FMODE_EXCL, _dm_claim_ptr); |
| if (IS_ERR(bdev)) |
| return PTR_ERR(bdev); |
| |
| r = bd_link_disk_holder(bdev, dm_disk(md)); |
| if (r) { |
| blkdev_put(bdev, td->dm_dev.mode | FMODE_EXCL); |
| return r; |
| } |
| |
| td->dm_dev.bdev = bdev; |
| td->dm_dev.dax_dev = dax_get_by_host(bdev->bd_disk->disk_name); |
| return 0; |
| } |
| |
| /* |
| * Close a table device that we've been using. |
| */ |
| static void close_table_device(struct table_device *td, struct mapped_device *md) |
| { |
| if (!td->dm_dev.bdev) |
| return; |
| |
| bd_unlink_disk_holder(td->dm_dev.bdev, dm_disk(md)); |
| blkdev_put(td->dm_dev.bdev, td->dm_dev.mode | FMODE_EXCL); |
| put_dax(td->dm_dev.dax_dev); |
| td->dm_dev.bdev = NULL; |
| td->dm_dev.dax_dev = NULL; |
| } |
| |
| static struct table_device *find_table_device(struct list_head *l, dev_t dev, |
| fmode_t mode) { |
| struct table_device *td; |
| |
| list_for_each_entry(td, l, list) |
| if (td->dm_dev.bdev->bd_dev == dev && td->dm_dev.mode == mode) |
| return td; |
| |
| return NULL; |
| } |
| |
| int dm_get_table_device(struct mapped_device *md, dev_t dev, fmode_t mode, |
| struct dm_dev **result) { |
| int r; |
| struct table_device *td; |
| |
| mutex_lock(&md->table_devices_lock); |
| td = find_table_device(&md->table_devices, dev, mode); |
| if (!td) { |
| td = kmalloc_node(sizeof(*td), GFP_KERNEL, md->numa_node_id); |
| if (!td) { |
| mutex_unlock(&md->table_devices_lock); |
| return -ENOMEM; |
| } |
| |
| td->dm_dev.mode = mode; |
| td->dm_dev.bdev = NULL; |
| |
| if ((r = open_table_device(td, dev, md))) { |
| mutex_unlock(&md->table_devices_lock); |
| kfree(td); |
| return r; |
| } |
| |
| format_dev_t(td->dm_dev.name, dev); |
| |
| refcount_set(&td->count, 1); |
| list_add(&td->list, &md->table_devices); |
| } else { |
| refcount_inc(&td->count); |
| } |
| mutex_unlock(&md->table_devices_lock); |
| |
| *result = &td->dm_dev; |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(dm_get_table_device); |
| |
| void dm_put_table_device(struct mapped_device *md, struct dm_dev *d) |
| { |
| struct table_device *td = container_of(d, struct table_device, dm_dev); |
| |
| mutex_lock(&md->table_devices_lock); |
| if (refcount_dec_and_test(&td->count)) { |
| close_table_device(td, md); |
| list_del(&td->list); |
| kfree(td); |
| } |
| mutex_unlock(&md->table_devices_lock); |
| } |
| EXPORT_SYMBOL(dm_put_table_device); |
| |
| static void free_table_devices(struct list_head *devices) |
| { |
| struct list_head *tmp, *next; |
| |
| list_for_each_safe(tmp, next, devices) { |
| struct table_device *td = list_entry(tmp, struct table_device, list); |
| |
| DMWARN("dm_destroy: %s still exists with %d references", |
| td->dm_dev.name, refcount_read(&td->count)); |
| kfree(td); |
| } |
| } |
| |
| /* |
| * Get the geometry associated with a dm device |
| */ |
| int dm_get_geometry(struct mapped_device *md, struct hd_geometry *geo) |
| { |
| *geo = md->geometry; |
| |
| return 0; |
| } |
| |
| /* |
| * Set the geometry of a device. |
| */ |
| int dm_set_geometry(struct mapped_device *md, struct hd_geometry *geo) |
| { |
| sector_t sz = (sector_t)geo->cylinders * geo->heads * geo->sectors; |
| |
| if (geo->start > sz) { |
| DMWARN("Start sector is beyond the geometry limits."); |
| return -EINVAL; |
| } |
| |
| md->geometry = *geo; |
| |
| return 0; |
| } |
| |
| static int __noflush_suspending(struct mapped_device *md) |
| { |
| return test_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
| } |
| |
| /* |
| * Decrements the number of outstanding ios that a bio has been |
| * cloned into, completing the original io if necc. |
| */ |
| static void dec_pending(struct dm_io *io, blk_status_t error) |
| { |
| unsigned long flags; |
| blk_status_t io_error; |
| struct bio *bio; |
| struct mapped_device *md = io->md; |
| |
| /* Push-back supersedes any I/O errors */ |
| if (unlikely(error)) { |
| spin_lock_irqsave(&io->endio_lock, flags); |
| if (!(io->status == BLK_STS_DM_REQUEUE && __noflush_suspending(md))) |
| io->status = error; |
| spin_unlock_irqrestore(&io->endio_lock, flags); |
| } |
| |
| if (atomic_dec_and_test(&io->io_count)) { |
| if (io->status == BLK_STS_DM_REQUEUE) { |
| /* |
| * Target requested pushing back the I/O. |
| */ |
| spin_lock_irqsave(&md->deferred_lock, flags); |
| if (__noflush_suspending(md)) |
| /* NOTE early return due to BLK_STS_DM_REQUEUE below */ |
| bio_list_add_head(&md->deferred, io->orig_bio); |
| else |
| /* noflush suspend was interrupted. */ |
| io->status = BLK_STS_IOERR; |
| spin_unlock_irqrestore(&md->deferred_lock, flags); |
| } |
| |
| io_error = io->status; |
| bio = io->orig_bio; |
| end_io_acct(io); |
| free_io(md, io); |
| |
| if (io_error == BLK_STS_DM_REQUEUE) |
| return; |
| |
| if ((bio->bi_opf & REQ_PREFLUSH) && bio->bi_iter.bi_size) { |
| /* |
| * Preflush done for flush with data, reissue |
| * without REQ_PREFLUSH. |
| */ |
| bio->bi_opf &= ~REQ_PREFLUSH; |
| queue_io(md, bio); |
| } else { |
| /* done with normal IO or empty flush */ |
| if (io_error) |
| bio->bi_status = io_error; |
| bio_endio(bio); |
| } |
| } |
| } |
| |
| void disable_write_same(struct mapped_device *md) |
| { |
| struct queue_limits *limits = dm_get_queue_limits(md); |
| |
| /* device doesn't really support WRITE SAME, disable it */ |
| limits->max_write_same_sectors = 0; |
| } |
| |
| void disable_write_zeroes(struct mapped_device *md) |
| { |
| struct queue_limits *limits = dm_get_queue_limits(md); |
| |
| /* device doesn't really support WRITE ZEROES, disable it */ |
| limits->max_write_zeroes_sectors = 0; |
| } |
| |
| static void clone_endio(struct bio *bio) |
| { |
| blk_status_t error = bio->bi_status; |
| struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
| struct dm_io *io = tio->io; |
| struct mapped_device *md = tio->io->md; |
| dm_endio_fn endio = tio->ti->type->end_io; |
| |
| if (unlikely(error == BLK_STS_TARGET) && md->type != DM_TYPE_NVME_BIO_BASED) { |
| if (bio_op(bio) == REQ_OP_WRITE_SAME && |
| !bio->bi_disk->queue->limits.max_write_same_sectors) |
| disable_write_same(md); |
| if (bio_op(bio) == REQ_OP_WRITE_ZEROES && |
| !bio->bi_disk->queue->limits.max_write_zeroes_sectors) |
| disable_write_zeroes(md); |
| } |
| |
| if (endio) { |
| int r = endio(tio->ti, bio, &error); |
| switch (r) { |
| case DM_ENDIO_REQUEUE: |
| error = BLK_STS_DM_REQUEUE; |
| /*FALLTHRU*/ |
| case DM_ENDIO_DONE: |
| break; |
| case DM_ENDIO_INCOMPLETE: |
| /* The target will handle the io */ |
| return; |
| default: |
| DMWARN("unimplemented target endio return value: %d", r); |
| BUG(); |
| } |
| } |
| |
| free_tio(tio); |
| dec_pending(io, error); |
| } |
| |
| /* |
| * Return maximum size of I/O possible at the supplied sector up to the current |
| * target boundary. |
| */ |
| static sector_t max_io_len_target_boundary(sector_t sector, struct dm_target *ti) |
| { |
| sector_t target_offset = dm_target_offset(ti, sector); |
| |
| return ti->len - target_offset; |
| } |
| |
| static sector_t max_io_len(sector_t sector, struct dm_target *ti) |
| { |
| sector_t len = max_io_len_target_boundary(sector, ti); |
| sector_t offset, max_len; |
| |
| /* |
| * Does the target need to split even further? |
| */ |
| if (ti->max_io_len) { |
| offset = dm_target_offset(ti, sector); |
| if (unlikely(ti->max_io_len & (ti->max_io_len - 1))) |
| max_len = sector_div(offset, ti->max_io_len); |
| else |
| max_len = offset & (ti->max_io_len - 1); |
| max_len = ti->max_io_len - max_len; |
| |
| if (len > max_len) |
| len = max_len; |
| } |
| |
| return len; |
| } |
| |
| int dm_set_target_max_io_len(struct dm_target *ti, sector_t len) |
| { |
| if (len > UINT_MAX) { |
| DMERR("Specified maximum size of target IO (%llu) exceeds limit (%u)", |
| (unsigned long long)len, UINT_MAX); |
| ti->error = "Maximum size of target IO is too large"; |
| return -EINVAL; |
| } |
| |
| /* |
| * BIO based queue uses its own splitting. When multipage bvecs |
| * is switched on, size of the incoming bio may be too big to |
| * be handled in some targets, such as crypt. |
| * |
| * When these targets are ready for the big bio, we can remove |
| * the limit. |
| */ |
| ti->max_io_len = min_t(uint32_t, len, BIO_MAX_PAGES * PAGE_SIZE); |
| |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(dm_set_target_max_io_len); |
| |
| static struct dm_target *dm_dax_get_live_target(struct mapped_device *md, |
| sector_t sector, int *srcu_idx) |
| __acquires(md->io_barrier) |
| { |
| struct dm_table *map; |
| struct dm_target *ti; |
| |
| map = dm_get_live_table(md, srcu_idx); |
| if (!map) |
| return NULL; |
| |
| ti = dm_table_find_target(map, sector); |
| if (!dm_target_is_valid(ti)) |
| return NULL; |
| |
| return ti; |
| } |
| |
| static long dm_dax_direct_access(struct dax_device *dax_dev, pgoff_t pgoff, |
| long nr_pages, void **kaddr, pfn_t *pfn) |
| { |
| struct mapped_device *md = dax_get_private(dax_dev); |
| sector_t sector = pgoff * PAGE_SECTORS; |
| struct dm_target *ti; |
| long len, ret = -EIO; |
| int srcu_idx; |
| |
| ti = dm_dax_get_live_target(md, sector, &srcu_idx); |
| |
| if (!ti) |
| goto out; |
| if (!ti->type->direct_access) |
| goto out; |
| len = max_io_len(sector, ti) / PAGE_SECTORS; |
| if (len < 1) |
| goto out; |
| nr_pages = min(len, nr_pages); |
| if (ti->type->direct_access) |
| ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn); |
| |
| out: |
| dm_put_live_table(md, srcu_idx); |
| |
| return ret; |
| } |
| |
| static size_t dm_dax_copy_from_iter(struct dax_device *dax_dev, pgoff_t pgoff, |
| void *addr, size_t bytes, struct iov_iter *i) |
| { |
| struct mapped_device *md = dax_get_private(dax_dev); |
| sector_t sector = pgoff * PAGE_SECTORS; |
| struct dm_target *ti; |
| long ret = 0; |
| int srcu_idx; |
| |
| ti = dm_dax_get_live_target(md, sector, &srcu_idx); |
| |
| if (!ti) |
| goto out; |
| if (!ti->type->dax_copy_from_iter) { |
| ret = copy_from_iter(addr, bytes, i); |
| goto out; |
| } |
| ret = ti->type->dax_copy_from_iter(ti, pgoff, addr, bytes, i); |
| out: |
| dm_put_live_table(md, srcu_idx); |
| |
| return ret; |
| } |
| |
| static size_t dm_dax_copy_to_iter(struct dax_device *dax_dev, pgoff_t pgoff, |
| void *addr, size_t bytes, struct iov_iter *i) |
| { |
| struct mapped_device *md = dax_get_private(dax_dev); |
| sector_t sector = pgoff * PAGE_SECTORS; |
| struct dm_target *ti; |
| long ret = 0; |
| int srcu_idx; |
| |
| ti = dm_dax_get_live_target(md, sector, &srcu_idx); |
| |
| if (!ti) |
| goto out; |
| if (!ti->type->dax_copy_to_iter) { |
| ret = copy_to_iter(addr, bytes, i); |
| goto out; |
| } |
| ret = ti->type->dax_copy_to_iter(ti, pgoff, addr, bytes, i); |
| out: |
| dm_put_live_table(md, srcu_idx); |
| |
| return ret; |
| } |
| |
| /* |
| * A target may call dm_accept_partial_bio only from the map routine. It is |
| * allowed for all bio types except REQ_PREFLUSH and REQ_OP_ZONE_RESET. |
| * |
| * dm_accept_partial_bio informs the dm that the target only wants to process |
| * additional n_sectors sectors of the bio and the rest of the data should be |
| * sent in a next bio. |
| * |
| * A diagram that explains the arithmetics: |
| * +--------------------+---------------+-------+ |
| * | 1 | 2 | 3 | |
| * +--------------------+---------------+-------+ |
| * |
| * <-------------- *tio->len_ptr ---------------> |
| * <------- bi_size -------> |
| * <-- n_sectors --> |
| * |
| * Region 1 was already iterated over with bio_advance or similar function. |
| * (it may be empty if the target doesn't use bio_advance) |
| * Region 2 is the remaining bio size that the target wants to process. |
| * (it may be empty if region 1 is non-empty, although there is no reason |
| * to make it empty) |
| * The target requires that region 3 is to be sent in the next bio. |
| * |
| * If the target wants to receive multiple copies of the bio (via num_*bios, etc), |
| * the partially processed part (the sum of regions 1+2) must be the same for all |
| * copies of the bio. |
| */ |
| void dm_accept_partial_bio(struct bio *bio, unsigned n_sectors) |
| { |
| struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
| unsigned bi_size = bio->bi_iter.bi_size >> SECTOR_SHIFT; |
| BUG_ON(bio->bi_opf & REQ_PREFLUSH); |
| BUG_ON(bi_size > *tio->len_ptr); |
| BUG_ON(n_sectors > bi_size); |
| *tio->len_ptr -= bi_size - n_sectors; |
| bio->bi_iter.bi_size = n_sectors << SECTOR_SHIFT; |
| } |
| EXPORT_SYMBOL_GPL(dm_accept_partial_bio); |
| |
| /* |
| * The zone descriptors obtained with a zone report indicate |
| * zone positions within the target device. The zone descriptors |
| * must be remapped to match their position within the dm device. |
| * A target may call dm_remap_zone_report after completion of a |
| * REQ_OP_ZONE_REPORT bio to remap the zone descriptors obtained |
| * from the target device mapping to the dm device. |
| */ |
| void dm_remap_zone_report(struct dm_target *ti, struct bio *bio, sector_t start) |
| { |
| #ifdef CONFIG_BLK_DEV_ZONED |
| struct dm_target_io *tio = container_of(bio, struct dm_target_io, clone); |
| struct bio *report_bio = tio->io->orig_bio; |
| struct blk_zone_report_hdr *hdr = NULL; |
| struct blk_zone *zone; |
| unsigned int nr_rep = 0; |
| unsigned int ofst; |
| struct bio_vec bvec; |
| struct bvec_iter iter; |
| void *addr; |
| |
| if (bio->bi_status) |
| return; |
| |
| /* |
| * Remap the start sector of the reported zones. For sequential zones, |
| * also remap the write pointer position. |
| */ |
| bio_for_each_segment(bvec, report_bio, iter) { |
| addr = kmap_atomic(bvec.bv_page); |
| |
| /* Remember the report header in the first page */ |
| if (!hdr) { |
| hdr = addr; |
| ofst = sizeof(struct blk_zone_report_hdr); |
| } else |
| ofst = 0; |
| |
| /* Set zones start sector */ |
| while (hdr->nr_zones && ofst < bvec.bv_len) { |
| zone = addr + ofst; |
| if (zone->start >= start + ti->len) { |
| hdr->nr_zones = 0; |
| break; |
| } |
| zone->start = zone->start + ti->begin - start; |
| if (zone->type != BLK_ZONE_TYPE_CONVENTIONAL) { |
| if (zone->cond == BLK_ZONE_COND_FULL) |
| zone->wp = zone->start + zone->len; |
| else if (zone->cond == BLK_ZONE_COND_EMPTY) |
| zone->wp = zone->start; |
| else |
| zone->wp = zone->wp + ti->begin - start; |
| } |
| ofst += sizeof(struct blk_zone); |
| hdr->nr_zones--; |
| nr_rep++; |
| } |
| |
| if (addr != hdr) |
| kunmap_atomic(addr); |
| |
| if (!hdr->nr_zones) |
| break; |
| } |
| |
| if (hdr) { |
| hdr->nr_zones = nr_rep; |
| kunmap_atomic(hdr); |
| } |
| |
| bio_advance(report_bio, report_bio->bi_iter.bi_size); |
| |
| #else /* !CONFIG_BLK_DEV_ZONED */ |
| bio->bi_status = BLK_STS_NOTSUPP; |
| #endif |
| } |
| EXPORT_SYMBOL_GPL(dm_remap_zone_report); |
| |
| static blk_qc_t __map_bio(struct dm_target_io *tio) |
| { |
| int r; |
| sector_t sector; |
| struct bio *clone = &tio->clone; |
| struct dm_io *io = tio->io; |
| struct mapped_device *md = io->md; |
| struct dm_target *ti = tio->ti; |
| blk_qc_t ret = BLK_QC_T_NONE; |
| |
| clone->bi_end_io = clone_endio; |
| |
| /* |
| * Map the clone. If r == 0 we don't need to do |
| * anything, the target has assumed ownership of |
| * this io. |
| */ |
| atomic_inc(&io->io_count); |
| sector = clone->bi_iter.bi_sector; |
| |
| r = ti->type->map(ti, clone); |
| switch (r) { |
| case DM_MAPIO_SUBMITTED: |
| break; |
| case DM_MAPIO_REMAPPED: |
| /* the bio has been remapped so dispatch it */ |
| trace_block_bio_remap(clone->bi_disk->queue, clone, |
| bio_dev(io->orig_bio), sector); |
| if (md->type == DM_TYPE_NVME_BIO_BASED) |
| ret = direct_make_request(clone); |
| else |
| ret = generic_make_request(clone); |
| break; |
| case DM_MAPIO_KILL: |
| free_tio(tio); |
| dec_pending(io, BLK_STS_IOERR); |
| break; |
| case DM_MAPIO_REQUEUE: |
| free_tio(tio); |
| dec_pending(io, BLK_STS_DM_REQUEUE); |
| break; |
| default: |
| DMWARN("unimplemented target map return value: %d", r); |
| BUG(); |
| } |
| |
| return ret; |
| } |
| |
| static void bio_setup_sector(struct bio *bio, sector_t sector, unsigned len) |
| { |
| bio->bi_iter.bi_sector = sector; |
| bio->bi_iter.bi_size = to_bytes(len); |
| } |
| |
| /* |
| * Creates a bio that consists of range of complete bvecs. |
| */ |
| static int clone_bio(struct dm_target_io *tio, struct bio *bio, |
| sector_t sector, unsigned len) |
| { |
| struct bio *clone = &tio->clone; |
| |
| __bio_clone_fast(clone, bio); |
| |
| if (unlikely(bio_integrity(bio) != NULL)) { |
| int r; |
| |
| if (unlikely(!dm_target_has_integrity(tio->ti->type) && |
| !dm_target_passes_integrity(tio->ti->type))) { |
| DMWARN("%s: the target %s doesn't support integrity data.", |
| dm_device_name(tio->io->md), |
| tio->ti->type->name); |
| return -EIO; |
| } |
| |
| r = bio_integrity_clone(clone, bio, GFP_NOIO); |
| if (r < 0) |
| return r; |
| } |
| |
| if (bio_op(bio) != REQ_OP_ZONE_REPORT) |
| bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); |
| clone->bi_iter.bi_size = to_bytes(len); |
| |
| if (unlikely(bio_integrity(bio) != NULL)) |
| bio_integrity_trim(clone); |
| |
| return 0; |
| } |
| |
| static void alloc_multiple_bios(struct bio_list *blist, struct clone_info *ci, |
| struct dm_target *ti, unsigned num_bios) |
| { |
| struct dm_target_io *tio; |
| int try; |
| |
| if (!num_bios) |
| return; |
| |
| if (num_bios == 1) { |
| tio = alloc_tio(ci, ti, 0, GFP_NOIO); |
| bio_list_add(blist, &tio->clone); |
| return; |
| } |
| |
| for (try = 0; try < 2; try++) { |
| int bio_nr; |
| struct bio *bio; |
| |
| if (try) |
| mutex_lock(&ci->io->md->table_devices_lock); |
| for (bio_nr = 0; bio_nr < num_bios; bio_nr++) { |
| tio = alloc_tio(ci, ti, bio_nr, try ? GFP_NOIO : GFP_NOWAIT); |
| if (!tio) |
| break; |
| |
| bio_list_add(blist, &tio->clone); |
| } |
| if (try) |
| mutex_unlock(&ci->io->md->table_devices_lock); |
| if (bio_nr == num_bios) |
| return; |
| |
| while ((bio = bio_list_pop(blist))) { |
| tio = container_of(bio, struct dm_target_io, clone); |
| free_tio(tio); |
| } |
| } |
| } |
| |
| static blk_qc_t __clone_and_map_simple_bio(struct clone_info *ci, |
| struct dm_target_io *tio, unsigned *len) |
| { |
| struct bio *clone = &tio->clone; |
| |
| tio->len_ptr = len; |
| |
| __bio_clone_fast(clone, ci->bio); |
| if (len) |
| bio_setup_sector(clone, ci->sector, *len); |
| |
| return __map_bio(tio); |
| } |
| |
| static void __send_duplicate_bios(struct clone_info *ci, struct dm_target *ti, |
| unsigned num_bios, unsigned *len) |
| { |
| struct bio_list blist = BIO_EMPTY_LIST; |
| struct bio *bio; |
| struct dm_target_io *tio; |
| |
| alloc_multiple_bios(&blist, ci, ti, num_bios); |
| |
| while ((bio = bio_list_pop(&blist))) { |
| tio = container_of(bio, struct dm_target_io, clone); |
| (void) __clone_and_map_simple_bio(ci, tio, len); |
| } |
| } |
| |
| static int __send_empty_flush(struct clone_info *ci) |
| { |
| unsigned target_nr = 0; |
| struct dm_target *ti; |
| |
| BUG_ON(bio_has_data(ci->bio)); |
| while ((ti = dm_table_get_target(ci->map, target_nr++))) |
| __send_duplicate_bios(ci, ti, ti->num_flush_bios, NULL); |
| |
| return 0; |
| } |
| |
| static int __clone_and_map_data_bio(struct clone_info *ci, struct dm_target *ti, |
| sector_t sector, unsigned *len) |
| { |
| struct bio *bio = ci->bio; |
| struct dm_target_io *tio; |
| int r; |
| |
| tio = alloc_tio(ci, ti, 0, GFP_NOIO); |
| tio->len_ptr = len; |
| r = clone_bio(tio, bio, sector, *len); |
| if (r < 0) { |
| free_tio(tio); |
| return r; |
| } |
| (void) __map_bio(tio); |
| |
| return 0; |
| } |
| |
| typedef unsigned (*get_num_bios_fn)(struct dm_target *ti); |
| |
| static unsigned get_num_discard_bios(struct dm_target *ti) |
| { |
| return ti->num_discard_bios; |
| } |
| |
| static unsigned get_num_secure_erase_bios(struct dm_target *ti) |
| { |
| return ti->num_secure_erase_bios; |
| } |
| |
| static unsigned get_num_write_same_bios(struct dm_target *ti) |
| { |
| return ti->num_write_same_bios; |
| } |
| |
| static unsigned get_num_write_zeroes_bios(struct dm_target *ti) |
| { |
| return ti->num_write_zeroes_bios; |
| } |
| |
| typedef bool (*is_split_required_fn)(struct dm_target *ti); |
| |
| static bool is_split_required_for_discard(struct dm_target *ti) |
| { |
| return ti->split_discard_bios; |
| } |
| |
| static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *ti, |
| get_num_bios_fn get_num_bios, |
| is_split_required_fn is_split_required) |
| { |
| unsigned len; |
| unsigned num_bios; |
| |
| /* |
| * Even though the device advertised support for this type of |
| * request, that does not mean every target supports it, and |
| * reconfiguration might also have changed that since the |
| * check was performed. |
| */ |
| num_bios = get_num_bios ? get_num_bios(ti) : 0; |
| if (!num_bios) |
| return -EOPNOTSUPP; |
| |
| if (is_split_required && !is_split_required(ti)) |
| len = min((sector_t)ci->sector_count, max_io_len_target_boundary(ci->sector, ti)); |
| else |
| len = min((sector_t)ci->sector_count, max_io_len(ci->sector, ti)); |
| |
| __send_duplicate_bios(ci, ti, num_bios, &len); |
| |
| ci->sector += len; |
| ci->sector_count -= len; |
| |
| return 0; |
| } |
| |
| static int __send_discard(struct clone_info *ci, struct dm_target *ti) |
| { |
| return __send_changing_extent_only(ci, ti, get_num_discard_bios, |
| is_split_required_for_discard); |
| } |
| |
| static int __send_secure_erase(struct clone_info *ci, struct dm_target *ti) |
| { |
| return __send_changing_extent_only(ci, ti, get_num_secure_erase_bios, NULL); |
| } |
| |
| static int __send_write_same(struct clone_info *ci, struct dm_target *ti) |
| { |
| return __send_changing_extent_only(ci, ti, get_num_write_same_bios, NULL); |
| } |
| |
| static int __send_write_zeroes(struct clone_info *ci, struct dm_target *ti) |
| { |
| return __send_changing_extent_only(ci, ti, get_num_write_zeroes_bios, NULL); |
| } |
| |
| static bool __process_abnormal_io(struct clone_info *ci, struct dm_target *ti, |
| int *result) |
| { |
| struct bio *bio = ci->bio; |
| |
| if (bio_op(bio) == REQ_OP_DISCARD) |
| *result = __send_discard(ci, ti); |
| else if (bio_op(bio) == REQ_OP_SECURE_ERASE) |
| *result = __send_secure_erase(ci, ti); |
| else if (bio_op(bio) == REQ_OP_WRITE_SAME) |
| *result = __send_write_same(ci, ti); |
| else if (bio_op(bio) == REQ_OP_WRITE_ZEROES) |
| *result = __send_write_zeroes(ci, ti); |
| else |
| return false; |
| |
| return true; |
| } |
| |
| /* |
| * Select the correct strategy for processing a non-flush bio. |
| */ |
| static int __split_and_process_non_flush(struct clone_info *ci) |
| { |
| struct bio *bio = ci->bio; |
| struct dm_target *ti; |
| unsigned len; |
| int r; |
| |
| ti = dm_table_find_target(ci->map, ci->sector); |
| if (!dm_target_is_valid(ti)) |
| return -EIO; |
| |
| if (unlikely(__process_abnormal_io(ci, ti, &r))) |
| return r; |
| |
| if (bio_op(bio) == REQ_OP_ZONE_REPORT) |
| len = ci->sector_count; |
| else |
| len = min_t(sector_t, max_io_len(ci->sector, ti), |
| ci->sector_count); |
| |
| r = __clone_and_map_data_bio(ci, ti, ci->sector, &len); |
| if (r < 0) |
| return r; |
| |
| ci->sector += len; |
| ci->sector_count -= len; |
| |
| return 0; |
| } |
| |
| static void init_clone_info(struct clone_info *ci, struct mapped_device *md, |
| struct dm_table *map, struct bio *bio) |
| { |
| ci->map = map; |
| ci->io = alloc_io(md, bio); |
| ci->sector = bio->bi_iter.bi_sector; |
| } |
| |
| /* |
| * Entry point to split a bio into clones and submit them to the targets. |
| */ |
| static blk_qc_t __split_and_process_bio(struct mapped_device *md, |
| struct dm_table *map, struct bio *bio) |
| { |
| struct clone_info ci; |
| blk_qc_t ret = BLK_QC_T_NONE; |
| int error = 0; |
| |
| if (unlikely(!map)) { |
| bio_io_error(bio); |
| return ret; |
| } |
| |
| init_clone_info(&ci, md, map, bio); |
| |
| if (bio->bi_opf & REQ_PREFLUSH) { |
| ci.bio = &ci.io->md->flush_bio; |
| ci.sector_count = 0; |
| error = __send_empty_flush(&ci); |
| /* dec_pending submits any data associated with flush */ |
| } else if (bio_op(bio) == REQ_OP_ZONE_RESET) { |
| ci.bio = bio; |
| ci.sector_count = 0; |
| error = __split_and_process_non_flush(&ci); |
| } else { |
| ci.bio = bio; |
| ci.sector_count = bio_sectors(bio); |
| while (ci.sector_count && !error) { |
| error = __split_and_process_non_flush(&ci); |
| if (current->bio_list && ci.sector_count && !error) { |
| /* |
| * Remainder must be passed to generic_make_request() |
| * so that it gets handled *after* bios already submitted |
| * have been completely processed. |
| * We take a clone of the original to store in |
| * ci.io->orig_bio to be used by end_io_acct() and |
| * for dec_pending to use for completion handling. |
| * As this path is not used for REQ_OP_ZONE_REPORT, |
| * the usage of io->orig_bio in dm_remap_zone_report() |
| * won't be affected by this reassignment. |
| */ |
| struct bio *b = bio_clone_bioset(bio, GFP_NOIO, |
| &md->queue->bio_split); |
| ci.io->orig_bio = b; |
| bio_advance(bio, (bio_sectors(bio) - ci.sector_count) << 9); |
| bio_chain(b, bio); |
| ret = generic_make_request(bio); |
| break; |
| } |
| } |
| } |
| |
| /* drop the extra reference count */ |
| dec_pending(ci.io, errno_to_blk_status(error)); |
| return ret; |
| } |
| |
| /* |
| * Optimized variant of __split_and_process_bio that leverages the |
| * fact that targets that use it do _not_ have a need to split bios. |
| */ |
| static blk_qc_t __process_bio(struct mapped_device *md, |
| struct dm_table *map, struct bio *bio) |
| { |
| struct clone_info ci; |
| blk_qc_t ret = BLK_QC_T_NONE; |
| int error = 0; |
| |
| if (unlikely(!map)) { |
| bio_io_error(bio); |
| return ret; |
| } |
| |
| init_clone_info(&ci, md, map, bio); |
| |
| if (bio->bi_opf & REQ_PREFLUSH) { |
| ci.bio = &ci.io->md->flush_bio; |
| ci.sector_count = 0; |
| error = __send_empty_flush(&ci); |
| /* dec_pending submits any data associated with flush */ |
| } else { |
| struct dm_target *ti = md->immutable_target; |
| struct dm_target_io *tio; |
| |
| /* |
| * Defend against IO still getting in during teardown |
| * - as was seen for a time with nvme-fcloop |
| */ |
| if (unlikely(WARN_ON_ONCE(!ti || !dm_target_is_valid(ti)))) { |
| error = -EIO; |
| goto out; |
| } |
| |
| ci.bio = bio; |
| ci.sector_count = bio_sectors(bio); |
| if (unlikely(__process_abnormal_io(&ci, ti, &error))) |
| goto out; |
| |
| tio = alloc_tio(&ci, ti, 0, GFP_NOIO); |
| ret = __clone_and_map_simple_bio(&ci, tio, NULL); |
| } |
| out: |
| /* drop the extra reference count */ |
| dec_pending(ci.io, errno_to_blk_status(error)); |
| return ret; |
| } |
| |
| typedef blk_qc_t (process_bio_fn)(struct mapped_device *, struct dm_table *, struct bio *); |
| |
| static blk_qc_t __dm_make_request(struct request_queue *q, struct bio *bio, |
| process_bio_fn process_bio) |
| { |
| struct mapped_device *md = q->queuedata; |
| blk_qc_t ret = BLK_QC_T_NONE; |
| int srcu_idx; |
| struct dm_table *map; |
| |
| map = dm_get_live_table(md, &srcu_idx); |
| |
| /* if we're suspended, we have to queue this io for later */ |
| if (unlikely(test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags))) { |
| dm_put_live_table(md, srcu_idx); |
| |
| if (!(bio->bi_opf & REQ_RAHEAD)) |
| queue_io(md, bio); |
| else |
| bio_io_error(bio); |
| return ret; |
| } |
| |
| ret = process_bio(md, map, bio); |
| |
| dm_put_live_table(md, srcu_idx); |
| return ret; |
| } |
| |
| /* |
| * The request function that remaps the bio to one target and |
| * splits off any remainder. |
| */ |
| static blk_qc_t dm_make_request(struct request_queue *q, struct bio *bio) |
| { |
| return __dm_make_request(q, bio, __split_and_process_bio); |
| } |
| |
| static blk_qc_t dm_make_request_nvme(struct request_queue *q, struct bio *bio) |
| { |
| return __dm_make_request(q, bio, __process_bio); |
| } |
| |
| static int dm_any_congested(void *congested_data, int bdi_bits) |
| { |
| int r = bdi_bits; |
| struct mapped_device *md = congested_data; |
| struct dm_table *map; |
| |
| if (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
| if (dm_request_based(md)) { |
| /* |
| * With request-based DM we only need to check the |
| * top-level queue for congestion. |
| */ |
| r = md->queue->backing_dev_info->wb.state & bdi_bits; |
| } else { |
| map = dm_get_live_table_fast(md); |
| if (map) |
| r = dm_table_any_congested(map, bdi_bits); |
| dm_put_live_table_fast(md); |
| } |
| } |
| |
| return r; |
| } |
| |
| /*----------------------------------------------------------------- |
| * An IDR is used to keep track of allocated minor numbers. |
| *---------------------------------------------------------------*/ |
| static void free_minor(int minor) |
| { |
| spin_lock(&_minor_lock); |
| idr_remove(&_minor_idr, minor); |
| spin_unlock(&_minor_lock); |
| } |
| |
| /* |
| * See if the device with a specific minor # is free. |
| */ |
| static int specific_minor(int minor) |
| { |
| int r; |
| |
| if (minor >= (1 << MINORBITS)) |
| return -EINVAL; |
| |
| idr_preload(GFP_KERNEL); |
| spin_lock(&_minor_lock); |
| |
| r = idr_alloc(&_minor_idr, MINOR_ALLOCED, minor, minor + 1, GFP_NOWAIT); |
| |
| spin_unlock(&_minor_lock); |
| idr_preload_end(); |
| if (r < 0) |
| return r == -ENOSPC ? -EBUSY : r; |
| return 0; |
| } |
| |
| static int next_free_minor(int *minor) |
| { |
| int r; |
| |
| idr_preload(GFP_KERNEL); |
| spin_lock(&_minor_lock); |
| |
| r = idr_alloc(&_minor_idr, MINOR_ALLOCED, 0, 1 << MINORBITS, GFP_NOWAIT); |
| |
| spin_unlock(&_minor_lock); |
| idr_preload_end(); |
| if (r < 0) |
| return r; |
| *minor = r; |
| return 0; |
| } |
| |
| static const struct block_device_operations dm_blk_dops; |
| static const struct dax_operations dm_dax_ops; |
| |
| static void dm_wq_work(struct work_struct *work); |
| |
| static void dm_init_normal_md_queue(struct mapped_device *md) |
| { |
| md->use_blk_mq = false; |
| |
| /* |
| * Initialize aspects of queue that aren't relevant for blk-mq |
| */ |
| md->queue->backing_dev_info->congested_fn = dm_any_congested; |
| } |
| |
| static void cleanup_mapped_device(struct mapped_device *md) |
| { |
| if (md->wq) |
| destroy_workqueue(md->wq); |
| if (md->kworker_task) |
| kthread_stop(md->kworker_task); |
| bioset_exit(&md->bs); |
| bioset_exit(&md->io_bs); |
| |
| if (md->dax_dev) { |
| kill_dax(md->dax_dev); |
| put_dax(md->dax_dev); |
| md->dax_dev = NULL; |
| } |
| |
| if (md->disk) { |
| spin_lock(&_minor_lock); |
| md->disk->private_data = NULL; |
| spin_unlock(&_minor_lock); |
| del_gendisk(md->disk); |
| put_disk(md->disk); |
| } |
| |
| if (md->queue) |
| blk_cleanup_queue(md->queue); |
| |
| cleanup_srcu_struct(&md->io_barrier); |
| |
| if (md->bdev) { |
| bdput(md->bdev); |
| md->bdev = NULL; |
| } |
| |
| mutex_destroy(&md->suspend_lock); |
| mutex_destroy(&md->type_lock); |
| mutex_destroy(&md->table_devices_lock); |
| |
| dm_mq_cleanup_mapped_device(md); |
| } |
| |
| /* |
| * Allocate and initialise a blank device with a given minor. |
| */ |
| static struct mapped_device *alloc_dev(int minor) |
| { |
| int r, numa_node_id = dm_get_numa_node(); |
| struct dax_device *dax_dev = NULL; |
| struct mapped_device *md; |
| void *old_md; |
| |
| md = kvzalloc_node(sizeof(*md), GFP_KERNEL, numa_node_id); |
| if (!md) { |
| DMWARN("unable to allocate device, out of memory."); |
| return NULL; |
| } |
| |
| if (!try_module_get(THIS_MODULE)) |
| goto bad_module_get; |
| |
| /* get a minor number for the dev */ |
| if (minor == DM_ANY_MINOR) |
| r = next_free_minor(&minor); |
| else |
| r = specific_minor(minor); |
| if (r < 0) |
| goto bad_minor; |
| |
| r = init_srcu_struct(&md->io_barrier); |
| if (r < 0) |
| goto bad_io_barrier; |
| |
| md->numa_node_id = numa_node_id; |
| md->use_blk_mq = dm_use_blk_mq_default(); |
| md->init_tio_pdu = false; |
| md->type = DM_TYPE_NONE; |
| mutex_init(&md->suspend_lock); |
| mutex_init(&md->type_lock); |
| mutex_init(&md->table_devices_lock); |
| spin_lock_init(&md->deferred_lock); |
| atomic_set(&md->holders, 1); |
| atomic_set(&md->open_count, 0); |
| atomic_set(&md->event_nr, 0); |
| atomic_set(&md->uevent_seq, 0); |
| INIT_LIST_HEAD(&md->uevent_list); |
| INIT_LIST_HEAD(&md->table_devices); |
| spin_lock_init(&md->uevent_lock); |
| |
| md->queue = blk_alloc_queue_node(GFP_KERNEL, numa_node_id, NULL); |
| if (!md->queue) |
| goto bad; |
| md->queue->queuedata = md; |
| md->queue->backing_dev_info->congested_data = md; |
| |
| md->disk = alloc_disk_node(1, md->numa_node_id); |
| if (!md->disk) |
| goto bad; |
| |
| atomic_set(&md->pending[0], 0); |
| atomic_set(&md->pending[1], 0); |
| init_waitqueue_head(&md->wait); |
| INIT_WORK(&md->work, dm_wq_work); |
| init_waitqueue_head(&md->eventq); |
| init_completion(&md->kobj_holder.completion); |
| md->kworker_task = NULL; |
| |
| md->disk->major = _major; |
| md->disk->first_minor = minor; |
| md->disk->fops = &dm_blk_dops; |
| md->disk->queue = md->queue; |
| md->disk->private_data = md; |
| sprintf(md->disk->disk_name, "dm-%d", minor); |
| |
| if (IS_ENABLED(CONFIG_DAX_DRIVER)) { |
| dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops); |
| if (!dax_dev) |
| goto bad; |
| } |
| md->dax_dev = dax_dev; |
| |
| add_disk_no_queue_reg(md->disk); |
| format_dev_t(md->name, MKDEV(_major, minor)); |
| |
| md->wq = alloc_workqueue("kdmflush", WQ_MEM_RECLAIM, 0); |
| if (!md->wq) |
| goto bad; |
| |
| md->bdev = bdget_disk(md->disk, 0); |
| if (!md->bdev) |
| goto bad; |
| |
| bio_init(&md->flush_bio, NULL, 0); |
| bio_set_dev(&md->flush_bio, md->bdev); |
| md->flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; |
| |
| dm_stats_init(&md->stats); |
| |
| /* Populate the mapping, nobody knows we exist yet */ |
| spin_lock(&_minor_lock); |
| old_md = idr_replace(&_minor_idr, md, minor); |
| spin_unlock(&_minor_lock); |
| |
| BUG_ON(old_md != MINOR_ALLOCED); |
| |
| return md; |
| |
| bad: |
| cleanup_mapped_device(md); |
| bad_io_barrier: |
| free_minor(minor); |
| bad_minor: |
| module_put(THIS_MODULE); |
| bad_module_get: |
| kvfree(md); |
| return NULL; |
| } |
| |
| static void unlock_fs(struct mapped_device *md); |
| |
| static void free_dev(struct mapped_device *md) |
| { |
| int minor = MINOR(disk_devt(md->disk)); |
| |
| unlock_fs(md); |
| |
| cleanup_mapped_device(md); |
| |
| free_table_devices(&md->table_devices); |
| dm_stats_cleanup(&md->stats); |
| free_minor(minor); |
| |
| module_put(THIS_MODULE); |
| kvfree(md); |
| } |
| |
| static int __bind_mempools(struct mapped_device *md, struct dm_table *t) |
| { |
| struct dm_md_mempools *p = dm_table_get_md_mempools(t); |
| int ret = 0; |
| |
| if (dm_table_bio_based(t)) { |
| /* |
| * The md may already have mempools that need changing. |
| * If so, reload bioset because front_pad may have changed |
| * because a different table was loaded. |
| */ |
| bioset_exit(&md->bs); |
| bioset_exit(&md->io_bs); |
| |
| } else if (bioset_initialized(&md->bs)) { |
| /* |
| * There's no need to reload with request-based dm |
| * because the size of front_pad doesn't change. |
| * Note for future: If you are to reload bioset, |
| * prep-ed requests in the queue may refer |
| * to bio from the old bioset, so you must walk |
| * through the queue to unprep. |
| */ |
| goto out; |
| } |
| |
| BUG_ON(!p || |
| bioset_initialized(&md->bs) || |
| bioset_initialized(&md->io_bs)); |
| |
| ret = bioset_init_from_src(&md->bs, &p->bs); |
| if (ret) |
| goto out; |
| ret = bioset_init_from_src(&md->io_bs, &p->io_bs); |
| if (ret) |
| bioset_exit(&md->bs); |
| out: |
| /* mempool bind completed, no longer need any mempools in the table */ |
| dm_table_free_md_mempools(t); |
| return ret; |
| } |
| |
| /* |
| * Bind a table to the device. |
| */ |
| static void event_callback(void *context) |
| { |
| unsigned long flags; |
| LIST_HEAD(uevents); |
| struct mapped_device *md = (struct mapped_device *) context; |
| |
| spin_lock_irqsave(&md->uevent_lock, flags); |
| list_splice_init(&md->uevent_list, &uevents); |
| spin_unlock_irqrestore(&md->uevent_lock, flags); |
| |
| dm_send_uevents(&uevents, &disk_to_dev(md->disk)->kobj); |
| |
| atomic_inc(&md->event_nr); |
| wake_up(&md->eventq); |
| dm_issue_global_event(); |
| } |
| |
| /* |
| * Protected by md->suspend_lock obtained by dm_swap_table(). |
| */ |
| static void __set_size(struct mapped_device *md, sector_t size) |
| { |
| lockdep_assert_held(&md->suspend_lock); |
| |
| set_capacity(md->disk, size); |
| |
| i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT); |
| } |
| |
| /* |
| * Returns old map, which caller must destroy. |
| */ |
| static struct dm_table *__bind(struct mapped_device *md, struct dm_table *t, |
| struct queue_limits *limits) |
| { |
| struct dm_table *old_map; |
| struct request_queue *q = md->queue; |
| bool request_based = dm_table_request_based(t); |
| sector_t size; |
| int ret; |
| |
| lockdep_assert_held(&md->suspend_lock); |
| |
| size = dm_table_get_size(t); |
| |
| /* |
| * Wipe any geometry if the size of the table changed. |
| */ |
| if (size != dm_get_size(md)) |
| memset(&md->geometry, 0, sizeof(md->geometry)); |
| |
| __set_size(md, size); |
| |
| dm_table_event_callback(t, event_callback, md); |
| |
| /* |
| * The queue hasn't been stopped yet, if the old table type wasn't |
| * for request-based during suspension. So stop it to prevent |
| * I/O mapping before resume. |
| * This must be done before setting the queue restrictions, |
| * because request-based dm may be run just after the setting. |
| */ |
| if (request_based) |
| dm_stop_queue(q); |
| |
| if (request_based || md->type == DM_TYPE_NVME_BIO_BASED) { |
| /* |
| * Leverage the fact that request-based DM targets and |
| * NVMe bio based targets are immutable singletons |
| * - used to optimize both dm_request_fn and dm_mq_queue_rq; |
| * and __process_bio. |
| */ |
| md->immutable_target = dm_table_get_immutable_target(t); |
| } |
| |
| ret = __bind_mempools(md, t); |
| if (ret) { |
| old_map = ERR_PTR(ret); |
| goto out; |
| } |
| |
| old_map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
| rcu_assign_pointer(md->map, (void *)t); |
| md->immutable_target_type = dm_table_get_immutable_target_type(t); |
| |
| dm_table_set_restrictions(t, q, limits); |
| if (old_map) |
| dm_sync_table(md); |
| |
| out: |
| return old_map; |
| } |
| |
| /* |
| * Returns unbound table for the caller to free. |
| */ |
| static struct dm_table *__unbind(struct mapped_device *md) |
| { |
| struct dm_table *map = rcu_dereference_protected(md->map, 1); |
| |
| if (!map) |
| return NULL; |
| |
| dm_table_event_callback(map, NULL, NULL); |
| RCU_INIT_POINTER(md->map, NULL); |
| dm_sync_table(md); |
| |
| return map; |
| } |
| |
| /* |
| * Constructor for a new device. |
| */ |
| int dm_create(int minor, struct mapped_device **result) |
| { |
| int r; |
| struct mapped_device *md; |
| |
| md = alloc_dev(minor); |
| if (!md) |
| return -ENXIO; |
| |
| r = dm_sysfs_init(md); |
| if (r) { |
| free_dev(md); |
| return r; |
| } |
| |
| *result = md; |
| return 0; |
| } |
| |
| /* |
| * Functions to manage md->type. |
| * All are required to hold md->type_lock. |
| */ |
| void dm_lock_md_type(struct mapped_device *md) |
| { |
| mutex_lock(&md->type_lock); |
| } |
| |
| void dm_unlock_md_type(struct mapped_device *md) |
| { |
| mutex_unlock(&md->type_lock); |
| } |
| |
| void dm_set_md_type(struct mapped_device *md, enum dm_queue_mode type) |
| { |
| BUG_ON(!mutex_is_locked(&md->type_lock)); |
| md->type = type; |
| } |
| |
| enum dm_queue_mode dm_get_md_type(struct mapped_device *md) |
| { |
| return md->type; |
| } |
| |
| struct target_type *dm_get_immutable_target_type(struct mapped_device *md) |
| { |
| return md->immutable_target_type; |
| } |
| |
| /* |
| * 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); |
| |
| /* |
| * Setup the DM device's queue based on md's type |
| */ |
| int dm_setup_md_queue(struct mapped_device *md, struct dm_table *t) |
| { |
| int r; |
| struct queue_limits limits; |
| enum dm_queue_mode type = dm_get_md_type(md); |
| |
| switch (type) { |
| case DM_TYPE_REQUEST_BASED: |
| dm_init_normal_md_queue(md); |
| r = dm_old_init_request_queue(md, t); |
| if (r) { |
| DMERR("Cannot initialize queue for request-based mapped device"); |
| return r; |
| } |
| break; |
| case DM_TYPE_MQ_REQUEST_BASED: |
| r = dm_mq_init_request_queue(md, t); |
| if (r) { |
| DMERR("Cannot initialize queue for request-based dm-mq mapped device"); |
| return r; |
| } |
| break; |
| case DM_TYPE_BIO_BASED: |
| case DM_TYPE_DAX_BIO_BASED: |
| dm_init_normal_md_queue(md); |
| blk_queue_make_request(md->queue, dm_make_request); |
| break; |
| case DM_TYPE_NVME_BIO_BASED: |
| dm_init_normal_md_queue(md); |
| blk_queue_make_request(md->queue, dm_make_request_nvme); |
| break; |
| case DM_TYPE_NONE: |
| WARN_ON_ONCE(true); |
| break; |
| } |
| |
| r = dm_calculate_queue_limits(t, &limits); |
| if (r) { |
| DMERR("Cannot calculate initial queue limits"); |
| return r; |
| } |
| dm_table_set_restrictions(t, md->queue, &limits); |
| blk_register_queue(md->disk); |
| |
| return 0; |
| } |
| |
| struct mapped_device *dm_get_md(dev_t dev) |
| { |
| struct mapped_device *md; |
| unsigned minor = MINOR(dev); |
| |
| if (MAJOR(dev) != _major || minor >= (1 << MINORBITS)) |
| return NULL; |
| |
| spin_lock(&_minor_lock); |
| |
| md = idr_find(&_minor_idr, minor); |
| if (!md || md == MINOR_ALLOCED || (MINOR(disk_devt(dm_disk(md))) != minor) || |
| test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) { |
| md = NULL; |
| goto out; |
| } |
| dm_get(md); |
| out: |
| spin_unlock(&_minor_lock); |
| |
| return md; |
| } |
| EXPORT_SYMBOL_GPL(dm_get_md); |
| |
| void *dm_get_mdptr(struct mapped_device *md) |
| { |
| return md->interface_ptr; |
| } |
| |
| void dm_set_mdptr(struct mapped_device *md, void *ptr) |
| { |
| md->interface_ptr = ptr; |
| } |
| |
| void dm_get(struct mapped_device *md) |
| { |
| atomic_inc(&md->holders); |
| BUG_ON(test_bit(DMF_FREEING, &md->flags)); |
| } |
| |
| int dm_hold(struct mapped_device *md) |
| { |
| spin_lock(&_minor_lock); |
| if (test_bit(DMF_FREEING, &md->flags)) { |
| spin_unlock(&_minor_lock); |
| return -EBUSY; |
| } |
| dm_get(md); |
| spin_unlock(&_minor_lock); |
| return 0; |
| } |
| EXPORT_SYMBOL_GPL(dm_hold); |
| |
| const char *dm_device_name(struct mapped_device *md) |
| { |
| return md->name; |
| } |
| EXPORT_SYMBOL_GPL(dm_device_name); |
| |
| static void __dm_destroy(struct mapped_device *md, bool wait) |
| { |
| struct dm_table *map; |
| int srcu_idx; |
| |
| might_sleep(); |
| |
| spin_lock(&_minor_lock); |
| idr_replace(&_minor_idr, MINOR_ALLOCED, MINOR(disk_devt(dm_disk(md)))); |
| set_bit(DMF_FREEING, &md->flags); |
| spin_unlock(&_minor_lock); |
| |
| blk_set_queue_dying(md->queue); |
| |
| if (dm_request_based(md) && md->kworker_task) |
| kthread_flush_worker(&md->kworker); |
| |
| /* |
| * Take suspend_lock so that presuspend and postsuspend methods |
| * do not race with internal suspend. |
| */ |
| mutex_lock(&md->suspend_lock); |
| map = dm_get_live_table(md, &srcu_idx); |
| if (!dm_suspended_md(md)) { |
| dm_table_presuspend_targets(map); |
| dm_table_postsuspend_targets(map); |
| } |
| /* dm_put_live_table must be before msleep, otherwise deadlock is possible */ |
| dm_put_live_table(md, srcu_idx); |
| mutex_unlock(&md->suspend_lock); |
| |
| /* |
| * Rare, but there may be I/O requests still going to complete, |
| * for example. Wait for all references to disappear. |
| * No one should increment the reference count of the mapped_device, |
| * after the mapped_device state becomes DMF_FREEING. |
| */ |
| if (wait) |
| while (atomic_read(&md->holders)) |
| msleep(1); |
| else if (atomic_read(&md->holders)) |
| DMWARN("%s: Forcibly removing mapped_device still in use! (%d users)", |
| dm_device_name(md), atomic_read(&md->holders)); |
| |
| dm_sysfs_exit(md); |
| dm_table_destroy(__unbind(md)); |
| free_dev(md); |
| } |
| |
| void dm_destroy(struct mapped_device *md) |
| { |
| __dm_destroy(md, true); |
| } |
| |
| void dm_destroy_immediate(struct mapped_device *md) |
| { |
| __dm_destroy(md, false); |
| } |
| |
| void dm_put(struct mapped_device *md) |
| { |
| atomic_dec(&md->holders); |
| } |
| EXPORT_SYMBOL_GPL(dm_put); |
| |
| static int dm_wait_for_completion(struct mapped_device *md, long task_state) |
| { |
| int r = 0; |
| DEFINE_WAIT(wait); |
| |
| while (1) { |
| prepare_to_wait(&md->wait, &wait, task_state); |
| |
| if (!md_in_flight(md)) |
| break; |
| |
| if (signal_pending_state(task_state, current)) { |
| r = -EINTR; |
| break; |
| } |
| |
| io_schedule(); |
| } |
| finish_wait(&md->wait, &wait); |
| |
| return r; |
| } |
| |
| /* |
| * Process the deferred bios |
| */ |
| static void dm_wq_work(struct work_struct *work) |
| { |
| struct mapped_device *md = container_of(work, struct mapped_device, |
| work); |
| struct bio *c; |
| int srcu_idx; |
| struct dm_table *map; |
| |
| map = dm_get_live_table(md, &srcu_idx); |
| |
| while (!test_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags)) { |
| spin_lock_irq(&md->deferred_lock); |
| c = bio_list_pop(&md->deferred); |
| spin_unlock_irq(&md->deferred_lock); |
| |
| if (!c) |
| break; |
| |
| if (dm_request_based(md)) |
| generic_make_request(c); |
| else |
| __split_and_process_bio(md, map, c); |
| } |
| |
| dm_put_live_table(md, srcu_idx); |
| } |
| |
| static void dm_queue_flush(struct mapped_device *md) |
| { |
| clear_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
| smp_mb__after_atomic(); |
| queue_work(md->wq, &md->work); |
| } |
| |
| /* |
| * Swap in a new table, returning the old one for the caller to destroy. |
| */ |
| struct dm_table *dm_swap_table(struct mapped_device *md, struct dm_table *table) |
| { |
| struct dm_table *live_map = NULL, *map = ERR_PTR(-EINVAL); |
| struct queue_limits limits; |
| int r; |
| |
| mutex_lock(&md->suspend_lock); |
| |
| /* device must be suspended */ |
| if (!dm_suspended_md(md)) |
| goto out; |
| |
| /* |
| * If the new table has no data devices, retain the existing limits. |
| * This helps multipath with queue_if_no_path if all paths disappear, |
| * then new I/O is queued based on these limits, and then some paths |
| * reappear. |
| */ |
| if (dm_table_has_no_data_devices(table)) { |
| live_map = dm_get_live_table_fast(md); |
| if (live_map) |
| limits = md->queue->limits; |
| dm_put_live_table_fast(md); |
| } |
| |
| if (!live_map) { |
| r = dm_calculate_queue_limits(table, &limits); |
| if (r) { |
| map = ERR_PTR(r); |
| goto out; |
| } |
| } |
| |
| map = __bind(md, table, &limits); |
| dm_issue_global_event(); |
| |
| out: |
| mutex_unlock(&md->suspend_lock); |
| return map; |
| } |
| |
| /* |
| * Functions to lock and unlock any filesystem running on the |
| * device. |
| */ |
| static int lock_fs(struct mapped_device *md) |
| { |
| int r; |
| |
| WARN_ON(md->frozen_sb); |
| |
| md->frozen_sb = freeze_bdev(md->bdev); |
| if (IS_ERR(md->frozen_sb)) { |
| r = PTR_ERR(md->frozen_sb); |
| md->frozen_sb = NULL; |
| return r; |
| } |
| |
| set_bit(DMF_FROZEN, &md->flags); |
| |
| return 0; |
| } |
| |
| static void unlock_fs(struct mapped_device *md) |
| { |
| if (!test_bit(DMF_FROZEN, &md->flags)) |
| return; |
| |
| thaw_bdev(md->bdev, md->frozen_sb); |
| md->frozen_sb = NULL; |
| clear_bit(DMF_FROZEN, &md->flags); |
| } |
| |
| /* |
| * @suspend_flags: DM_SUSPEND_LOCKFS_FLAG and/or DM_SUSPEND_NOFLUSH_FLAG |
| * @task_state: e.g. TASK_INTERRUPTIBLE or TASK_UNINTERRUPTIBLE |
| * @dmf_suspended_flag: DMF_SUSPENDED or DMF_SUSPENDED_INTERNALLY |
| * |
| * If __dm_suspend returns 0, the device is completely quiescent |
| * now. There is no request-processing activity. All new requests |
| * are being added to md->deferred list. |
| */ |
| static int __dm_suspend(struct mapped_device *md, struct dm_table *map, |
| unsigned suspend_flags, long task_state, |
| int dmf_suspended_flag) |
| { |
| bool do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG; |
| bool noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG; |
| int r; |
| |
| lockdep_assert_held(&md->suspend_lock); |
| |
| /* |
| * DMF_NOFLUSH_SUSPENDING must be set before presuspend. |
| * This flag is cleared before dm_suspend returns. |
| */ |
| if (noflush) |
| set_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
| else |
| pr_debug("%s: suspending with flush\n", dm_device_name(md)); |
| |
| /* |
| * This gets reverted if there's an error later and the targets |
| * provide the .presuspend_undo hook. |
| */ |
| dm_table_presuspend_targets(map); |
| |
| /* |
| * Flush I/O to the device. |
| * Any I/O submitted after lock_fs() may not be flushed. |
| * noflush takes precedence over do_lockfs. |
| * (lock_fs() flushes I/Os and waits for them to complete.) |
| */ |
| if (!noflush && do_lockfs) { |
| r = lock_fs(md); |
| if (r) { |
| dm_table_presuspend_undo_targets(map); |
| return r; |
| } |
| } |
| |
| /* |
| * Here we must make sure that no processes are submitting requests |
| * to target drivers i.e. no one may be executing |
| * __split_and_process_bio. This is called from dm_request and |
| * dm_wq_work. |
| * |
| * To get all processes out of __split_and_process_bio in dm_request, |
| * we take the write lock. To prevent any process from reentering |
| * __split_and_process_bio from dm_request and quiesce the thread |
| * (dm_wq_work), we set BMF_BLOCK_IO_FOR_SUSPEND and call |
| * flush_workqueue(md->wq). |
| */ |
| set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
| if (map) |
| synchronize_srcu(&md->io_barrier); |
| |
| /* |
| * Stop md->queue before flushing md->wq in case request-based |
| * dm defers requests to md->wq from md->queue. |
| */ |
| if (dm_request_based(md)) { |
| dm_stop_queue(md->queue); |
| if (md->kworker_task) |
| kthread_flush_worker(&md->kworker); |
| } |
| |
| flush_workqueue(md->wq); |
| |
| /* |
| * At this point no more requests are entering target request routines. |
| * We call dm_wait_for_completion to wait for all existing requests |
| * to finish. |
| */ |
| r = dm_wait_for_completion(md, task_state); |
| if (!r) |
| set_bit(dmf_suspended_flag, &md->flags); |
| |
| if (noflush) |
| clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags); |
| if (map) |
| synchronize_srcu(&md->io_barrier); |
| |
| /* were we interrupted ? */ |
| if (r < 0) { |
| dm_queue_flush(md); |
| |
| if (dm_request_based(md)) |
| dm_start_queue(md->queue); |
| |
| unlock_fs(md); |
| dm_table_presuspend_undo_targets(map); |
| /* pushback list is already flushed, so skip flush */ |
| } |
| |
| return r; |
| } |
| |
| /* |
| * We need to be able to change a mapping table under a mounted |
| * filesystem. For example we might want to move some data in |
| * the background. Before the table can be swapped with |
| * dm_bind_table, dm_suspend must be called to flush any in |
| * flight bios and ensure that any further io gets deferred. |
| */ |
| /* |
| * Suspend mechanism in request-based dm. |
| * |
| * 1. Flush all I/Os by lock_fs() if needed. |
| * 2. Stop dispatching any I/O by stopping the request_queue. |
| * 3. Wait for all in-flight I/Os to be completed or requeued. |
| * |
| * To abort suspend, start the request_queue. |
| */ |
| int dm_suspend(struct mapped_device *md, unsigned suspend_flags) |
| { |
| struct dm_table *map = NULL; |
| int r = 0; |
| |
| retry: |
| mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); |
| |
| if (dm_suspended_md(md)) { |
| r = -EINVAL; |
| goto out_unlock; |
| } |
| |
| if (dm_suspended_internally_md(md)) { |
| /* already internally suspended, wait for internal resume */ |
| mutex_unlock(&md->suspend_lock); |
| r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); |
| if (r) |
| return r; |
| goto retry; |
| } |
| |
| map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
| |
| r = __dm_suspend(md, map, suspend_flags, TASK_INTERRUPTIBLE, DMF_SUSPENDED); |
| if (r) |
| goto out_unlock; |
| |
| dm_table_postsuspend_targets(map); |
| |
| out_unlock: |
| mutex_unlock(&md->suspend_lock); |
| return r; |
| } |
| |
| static int __dm_resume(struct mapped_device *md, struct dm_table *map) |
| { |
| if (map) { |
| int r = dm_table_resume_targets(map); |
| if (r) |
| return r; |
| } |
| |
| dm_queue_flush(md); |
| |
| /* |
| * Flushing deferred I/Os must be done after targets are resumed |
| * so that mapping of targets can work correctly. |
| * Request-based dm is queueing the deferred I/Os in its request_queue. |
| */ |
| if (dm_request_based(md)) |
| dm_start_queue(md->queue); |
| |
| unlock_fs(md); |
| |
| return 0; |
| } |
| |
| int dm_resume(struct mapped_device *md) |
| { |
| int r; |
| struct dm_table *map = NULL; |
| |
| retry: |
| r = -EINVAL; |
| mutex_lock_nested(&md->suspend_lock, SINGLE_DEPTH_NESTING); |
| |
| if (!dm_suspended_md(md)) |
| goto out; |
| |
| if (dm_suspended_internally_md(md)) { |
| /* already internally suspended, wait for internal resume */ |
| mutex_unlock(&md->suspend_lock); |
| r = wait_on_bit(&md->flags, DMF_SUSPENDED_INTERNALLY, TASK_INTERRUPTIBLE); |
| if (r) |
| return r; |
| goto retry; |
| } |
| |
| map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
| if (!map || !dm_table_get_size(map)) |
| goto out; |
| |
| r = __dm_resume(md, map); |
| if (r) |
| goto out; |
| |
| clear_bit(DMF_SUSPENDED, &md->flags); |
| out: |
| mutex_unlock(&md->suspend_lock); |
| |
| return r; |
| } |
| |
| /* |
| * Internal suspend/resume works like userspace-driven suspend. It waits |
| * until all bios finish and prevents issuing new bios to the target drivers. |
| * It may be used only from the kernel. |
| */ |
| |
| static void __dm_internal_suspend(struct mapped_device *md, unsigned suspend_flags) |
| { |
| struct dm_table *map = NULL; |
| |
| lockdep_assert_held(&md->suspend_lock); |
| |
| if (md->internal_suspend_count++) |
| return; /* nested internal suspend */ |
| |
| if (dm_suspended_md(md)) { |
| set_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); |
| return; /* nest suspend */ |
| } |
| |
| map = rcu_dereference_protected(md->map, lockdep_is_held(&md->suspend_lock)); |
| |
| /* |
| * Using TASK_UNINTERRUPTIBLE because only NOFLUSH internal suspend is |
| * supported. Properly supporting a TASK_INTERRUPTIBLE internal suspend |
| * would require changing .presuspend to return an error -- avoid this |
| * until there is a need for more elaborate variants of internal suspend. |
| */ |
| (void) __dm_suspend(md, map, suspend_flags, TASK_UNINTERRUPTIBLE, |
| DMF_SUSPENDED_INTERNALLY); |
| |
| dm_table_postsuspend_targets(map); |
| } |
| |
| static void __dm_internal_resume(struct mapped_device *md) |
| { |
| BUG_ON(!md->internal_suspend_count); |
| |
| if (--md->internal_suspend_count) |
| return; /* resume from nested internal suspend */ |
| |
| if (dm_suspended_md(md)) |
| goto done; /* resume from nested suspend */ |
| |
| /* |
| * NOTE: existing callers don't need to call dm_table_resume_targets |
| * (which may fail -- so best to avoid it for now by passing NULL map) |
| */ |
| (void) __dm_resume(md, NULL); |
| |
| done: |
| clear_bit(DMF_SUSPENDED_INTERNALLY, &md->flags); |
| smp_mb__after_atomic(); |
| wake_up_bit(&md->flags, DMF_SUSPENDED_INTERNALLY); |
| } |
| |
| void dm_internal_suspend_noflush(struct mapped_device *md) |
| { |
| mutex_lock(&md->suspend_lock); |
| __dm_internal_suspend(md, DM_SUSPEND_NOFLUSH_FLAG); |
| mutex_unlock(&md->suspend_lock); |
| } |
| EXPORT_SYMBOL_GPL(dm_internal_suspend_noflush); |
| |
| void dm_internal_resume(struct mapped_device *md) |
| { |
| mutex_lock(&md->suspend_lock); |
| __dm_internal_resume(md); |
| mutex_unlock(&md->suspend_lock); |
| } |
| EXPORT_SYMBOL_GPL(dm_internal_resume); |
| |
| /* |
| * Fast variants of internal suspend/resume hold md->suspend_lock, |
| * which prevents interaction with userspace-driven suspend. |
| */ |
| |
| void dm_internal_suspend_fast(struct mapped_device *md) |
| { |
| mutex_lock(&md->suspend_lock); |
| if (dm_suspended_md(md) || dm_suspended_internally_md(md)) |
| return; |
| |
| set_bit(DMF_BLOCK_IO_FOR_SUSPEND, &md->flags); |
| synchronize_srcu(&md->io_barrier); |
| flush_workqueue(md->wq); |
| dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE); |
| } |
| EXPORT_SYMBOL_GPL(dm_internal_suspend_fast); |
| |
| void dm_internal_resume_fast(struct mapped_device *md) |
| { |
| if (dm_suspended_md(md) || dm_suspended_internally_md(md)) |
| goto done; |
| |
| dm_queue_flush(md); |
| |
| done: |
| mutex_unlock(&md->suspend_lock); |
| } |
| EXPORT_SYMBOL_GPL(dm_internal_resume_fast); |
| |
| /*----------------------------------------------------------------- |
| * Event notification. |
| *---------------------------------------------------------------*/ |
| int dm_kobject_uevent(struct mapped_device *md, enum kobject_action action, |
| unsigned cookie) |
| { |
| char udev_cookie[DM_COOKIE_LENGTH]; |
| char *envp[] = { udev_cookie, NULL }; |
| |
| if (!cookie) |
| return kobject_uevent(&disk_to_dev(md->disk)->kobj, action); |
| else { |
| snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u", |
| DM_COOKIE_ENV_VAR_NAME, cookie); |
| return kobject_uevent_env(&disk_to_dev(md->disk)->kobj, |
| action, envp); |
| } |
| } |
| |
| uint32_t dm_next_uevent_seq(struct mapped_device *md) |
| { |
| return atomic_add_return(1, &md->uevent_seq); |
| } |
| |
| uint32_t dm_get_event_nr(struct mapped_device *md) |
| { |
| return atomic_read(&md->event_nr); |
| } |
| |
| int dm_wait_event(struct mapped_device *md, int event_nr) |
| { |
| return wait_event_interruptible(md->eventq, |
| (event_nr != atomic_read(&md->event_nr))); |
| } |
| |
| void dm_uevent_add(struct mapped_device *md, struct list_head *elist) |
| { |
| unsigned long flags; |
| |
| spin_lock_irqsave(&md->uevent_lock, flags); |
| list_add(elist, &md->uevent_list); |
| spin_unlock_irqrestore(&md->uevent_lock, flags); |
| } |
| |
| /* |
| * The gendisk is only valid as long as you have a reference |
| * count on 'md'. |
| */ |
| struct gendisk *dm_disk(struct mapped_device *md) |
| { |
| return md->disk; |
| } |
| EXPORT_SYMBOL_GPL(dm_disk); |
| |
| struct kobject *dm_kobject(struct mapped_device *md) |
| { |
| return &md->kobj_holder.kobj; |
| } |
| |
| struct mapped_device *dm_get_from_kobject(struct kobject *kobj) |
| { |
| struct mapped_device *md; |
| |
| md = container_of(kobj, struct mapped_device, kobj_holder.kobj); |
| |
| spin_lock(&_minor_lock); |
| if (test_bit(DMF_FREEING, &md->flags) || dm_deleting_md(md)) { |
| md = NULL; |
| goto out; |
| } |
| dm_get(md); |
| out: |
| spin_unlock(&_minor_lock); |
| |
| return md; |
| } |
| |
| int dm_suspended_md(struct mapped_device *md) |
| { |
| return test_bit(DMF_SUSPENDED, &md->flags); |
| } |
| |
| int dm_suspended_internally_md(struct mapped_device *md) |
| { |
| return test_bit(DMF_SUSPENDED_INTERNALLY, &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)); |
| } |
| EXPORT_SYMBOL_GPL(dm_suspended); |
| |
| int dm_noflush_suspending(struct dm_target *ti) |
| { |
| return __noflush_suspending(dm_table_get_md(ti->table)); |
| } |
| EXPORT_SYMBOL_GPL(dm_noflush_suspending); |
| |
| struct dm_md_mempools *dm_alloc_md_mempools(struct mapped_device *md, enum dm_queue_mode type, |
| unsigned integrity, unsigned per_io_data_size, |
| unsigned min_pool_size) |
| { |
| struct dm_md_mempools *pools = kzalloc_node(sizeof(*pools), GFP_KERNEL, md->numa_node_id); |
| unsigned int pool_size = 0; |
| unsigned int front_pad, io_front_pad; |
| int ret; |
| |
| if (!pools) |
| return NULL; |
| |
| switch (type) { |
| case DM_TYPE_BIO_BASED: |
| case DM_TYPE_DAX_BIO_BASED: |
| case DM_TYPE_NVME_BIO_BASED: |
| pool_size = max(dm_get_reserved_bio_based_ios(), min_pool_size); |
| front_pad = roundup(per_io_data_size, __alignof__(struct dm_target_io)) + offsetof(struct dm_target_io, clone); |
| io_front_pad = roundup(front_pad, __alignof__(struct dm_io)) + offsetof(struct dm_io, tio); |
| ret = bioset_init(&pools->io_bs, pool_size, io_front_pad, 0); |
| if (ret) |
| goto out; |
| if (integrity && bioset_integrity_create(&pools->io_bs, pool_size)) |
| goto out; |
| break; |
| case DM_TYPE_REQUEST_BASED: |
| case DM_TYPE_MQ_REQUEST_BASED: |
| pool_size = max(dm_get_reserved_rq_based_ios(), min_pool_size); |
| front_pad = offsetof(struct dm_rq_clone_bio_info, clone); |
| /* per_io_data_size is used for blk-mq pdu at queue allocation */ |
| break; |
| default: |
| BUG(); |
| } |
| |
| ret = bioset_init(&pools->bs, pool_size, front_pad, 0); |
| if (ret) |
| goto out; |
| |
| if (integrity && bioset_integrity_create(&pools->bs, pool_size)) |
| goto out; |
| |
| return pools; |
| |
| out: |
| dm_free_md_mempools(pools); |
| |
| return NULL; |
| } |
| |
| void dm_free_md_mempools(struct dm_md_mempools *pools) |
| { |
| if (!pools) |
| return; |
| |
| bioset_exit(&pools->bs); |
| bioset_exit(&pools->io_bs); |
| |
| kfree(pools); |
| } |
| |
| struct dm_pr { |
| u64 old_key; |
| u64 new_key; |
| u32 flags; |
| bool fail_early; |
| }; |
| |
| static int dm_call_pr(struct block_device *bdev, iterate_devices_callout_fn fn, |
| void *data) |
| { |
| struct mapped_device *md = bdev->bd_disk->private_data; |
| struct dm_table *table; |
| struct dm_target *ti; |
| int ret = -ENOTTY, srcu_idx; |
| |
| table = dm_get_live_table(md, &srcu_idx); |
| if (!table || !dm_table_get_size(table)) |
| goto out; |
| |
| /* We only support devices that have a single target */ |
| if (dm_table_get_num_targets(table) != 1) |
| goto out; |
| ti = dm_table_get_target(table, 0); |
| |
| ret = -EINVAL; |
| if (!ti->type->iterate_devices) |
| goto out; |
| |
| ret = ti->type->iterate_devices(ti, fn, data); |
| out: |
| dm_put_live_table(md, srcu_idx); |
| return ret; |
| } |
| |
| /* |
| * For register / unregister we need to manually call out to every path. |
| */ |
| static int __dm_pr_register(struct dm_target *ti, struct dm_dev *dev, |
| sector_t start, sector_t len, void *data) |
| { |
| struct dm_pr *pr = data; |
| const struct pr_ops *ops = dev->bdev->bd_disk->fops->pr_ops; |
| |
| if (!ops || !ops->pr_register) |
| return -EOPNOTSUPP; |
| return ops->pr_register(dev->bdev, pr->old_key, pr->new_key, pr->flags); |
| } |
| |
| static int dm_pr_register(struct block_device *bdev, u64 old_key, u64 new_key, |
| u32 flags) |
| { |
| struct dm_pr pr = { |
| .old_key = old_key, |
| .new_key = new_key, |
| .flags = flags, |
| .fail_early = true, |
| }; |
| int ret; |
| |
| ret = dm_call_pr(bdev, __dm_pr_register, &pr); |
| if (ret && new_key) { |
| /* unregister all paths if we failed to register any path */ |
| pr.old_key = new_key; |
| pr.new_key = 0; |
| pr.flags = 0; |
| pr.fail_early = false; |
| dm_call_pr(bdev, __dm_pr_register, &pr); |
| } |
| |
| return ret; |
| } |
| |
| static int dm_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type, |
| u32 flags) |
| { |
| struct mapped_device *md = bdev->bd_disk->private_data; |
| const struct pr_ops *ops; |
| int r, srcu_idx; |
| |
| r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
| if (r < 0) |
| goto out; |
| |
| ops = bdev->bd_disk->fops->pr_ops; |
| if (ops && ops->pr_reserve) |
| r = ops->pr_reserve(bdev, key, type, flags); |
| else |
| r = -EOPNOTSUPP; |
| out: |
| dm_unprepare_ioctl(md, srcu_idx); |
| return r; |
| } |
| |
| static int dm_pr_release(struct block_device *bdev, u64 key, enum pr_type type) |
| { |
| struct mapped_device *md = bdev->bd_disk->private_data; |
| const struct pr_ops *ops; |
| int r, srcu_idx; |
| |
| r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
| if (r < 0) |
| goto out; |
| |
| ops = bdev->bd_disk->fops->pr_ops; |
| if (ops && ops->pr_release) |
| r = ops->pr_release(bdev, key, type); |
| else |
| r = -EOPNOTSUPP; |
| out: |
| dm_unprepare_ioctl(md, srcu_idx); |
| return r; |
| } |
| |
| static int dm_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key, |
| enum pr_type type, bool abort) |
| { |
| struct mapped_device *md = bdev->bd_disk->private_data; |
| const struct pr_ops *ops; |
| int r, srcu_idx; |
| |
| r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
| if (r < 0) |
| goto out; |
| |
| ops = bdev->bd_disk->fops->pr_ops; |
| if (ops && ops->pr_preempt) |
| r = ops->pr_preempt(bdev, old_key, new_key, type, abort); |
| else |
| r = -EOPNOTSUPP; |
| out: |
| dm_unprepare_ioctl(md, srcu_idx); |
| return r; |
| } |
| |
| static int dm_pr_clear(struct block_device *bdev, u64 key) |
| { |
| struct mapped_device *md = bdev->bd_disk->private_data; |
| const struct pr_ops *ops; |
| int r, srcu_idx; |
| |
| r = dm_prepare_ioctl(md, &srcu_idx, &bdev); |
| if (r < 0) |
| goto out; |
| |
| ops = bdev->bd_disk->fops->pr_ops; |
| if (ops && ops->pr_clear) |
| r = ops->pr_clear(bdev, key); |
| else |
| r = -EOPNOTSUPP; |
| out: |
| dm_unprepare_ioctl(md, srcu_idx); |
| return r; |
| } |
| |
| static const struct pr_ops dm_pr_ops = { |
| .pr_register = dm_pr_register, |
| .pr_reserve = dm_pr_reserve, |
| .pr_release = dm_pr_release, |
| .pr_preempt = dm_pr_preempt, |
| .pr_clear = dm_pr_clear, |
| }; |
| |
| static const struct block_device_operations dm_blk_dops = { |
| .open = dm_blk_open, |
| .release = dm_blk_close, |
| .ioctl = dm_blk_ioctl, |
| .getgeo = dm_blk_getgeo, |
| .pr_ops = &dm_pr_ops, |
| .owner = THIS_MODULE |
| }; |
| |
| static const struct dax_operations dm_dax_ops = { |
| .direct_access = dm_dax_direct_access, |
| .copy_from_iter = dm_dax_copy_from_iter, |
| .copy_to_iter = dm_dax_copy_to_iter, |
| }; |
| |
| /* |
| * module hooks |
| */ |
| module_init(dm_init); |
| 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(dm_numa_node, int, S_IRUGO | S_IWUSR); |
| MODULE_PARM_DESC(dm_numa_node, "NUMA node for DM device memory allocations"); |
| |
| MODULE_DESCRIPTION(DM_NAME " driver"); |
| MODULE_AUTHOR("Joe Thornber <dm-devel@redhat.com>"); |
| MODULE_LICENSE("GPL"); |