| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Mike Snitzer | 7192 | 52.62% | 79 | 24.92% |
| Christoph Hellwig | 1261 | 9.23% | 11 | 3.47% |
| Kiyoshi Ueda | 1036 | 7.58% | 18 | 5.68% |
| Mikulas Patocka | 755 | 5.52% | 44 | 13.88% |
| Dan J Williams | 595 | 4.35% | 6 | 1.89% |
| Alasdair G. Kergon | 472 | 3.45% | 30 | 9.46% |
| Alan Cox | 429 | 3.14% | 2 | 0.63% |
| Milan Broz | 238 | 1.74% | 12 | 3.79% |
| Andrew Morton | 225 | 1.65% | 12 | 3.79% |
| Damien Le Moal | 157 | 1.15% | 3 | 0.95% |
| Jens Axboe | 156 | 1.14% | 8 | 2.52% |
| Mike Anderson | 119 | 0.87% | 5 | 1.58% |
| Jeff Mahoney | 118 | 0.86% | 6 | 1.89% |
| Kent Overstreet | 95 | 0.70% | 5 | 1.58% |
| Bart Van Assche | 89 | 0.65% | 10 | 3.15% |
| Toshi Kani | 77 | 0.56% | 1 | 0.32% |
| Jun'ichi Nomura | 68 | 0.50% | 10 | 3.15% |
| Keith Busch | 63 | 0.46% | 2 | 0.63% |
| Denis Semakin | 61 | 0.45% | 1 | 0.32% |
| Neil Brown | 60 | 0.44% | 5 | 1.58% |
| Tejun Heo | 58 | 0.42% | 7 | 2.21% |
| Joe Thornber | 43 | 0.31% | 4 | 1.26% |
| Eric Dumazet | 28 | 0.20% | 1 | 0.32% |
| Kevin Corry | 27 | 0.20% | 2 | 0.63% |
| Darrick J. Wong | 23 | 0.17% | 1 | 0.32% |
| Hou Tao | 22 | 0.16% | 1 | 0.32% |
| Dennis Zhou | 22 | 0.16% | 1 | 0.32% |
| Michael Lass | 21 | 0.15% | 1 | 0.32% |
| David Teigland | 20 | 0.15% | 1 | 0.32% |
| Martin K. Petersen | 19 | 0.14% | 2 | 0.63% |
| Michael Christie | 15 | 0.11% | 2 | 0.63% |
| Elena Reshetova | 12 | 0.09% | 1 | 0.32% |
| Tahsin Erdogan | 8 | 0.06% | 1 | 0.32% |
| Michael Callahan | 8 | 0.06% | 1 | 0.32% |
| Nikanth Karthikesan | 8 | 0.06% | 1 | 0.32% |
| Hannes Reinecke | 8 | 0.06% | 1 | 0.32% |
| Al Viro | 6 | 0.04% | 1 | 0.32% |
| Sami Tolvanen | 5 | 0.04% | 1 | 0.32% |
| Peter Rajnoha | 5 | 0.04% | 1 | 0.32% |
| Edward Goggin | 5 | 0.04% | 1 | 0.32% |
| Minfei Huang | 5 | 0.04% | 1 | 0.32% |
| Peng Wang | 4 | 0.03% | 1 | 0.32% |
| Pranith Kumar | 4 | 0.03% | 1 | 0.32% |
| Linus Torvalds | 4 | 0.03% | 1 | 0.32% |
| Ingo Molnar | 3 | 0.02% | 1 | 0.32% |
| Richard Kennedy | 3 | 0.02% | 1 | 0.32% |
| Arjan van de Ven | 2 | 0.01% | 1 | 0.32% |
| Peter Osterlund | 2 | 0.01% | 1 | 0.32% |
| Jan Kara | 2 | 0.01% | 1 | 0.32% |
| Mark Rutland | 2 | 0.01% | 1 | 0.32% |
| Stefan Bader | 2 | 0.01% | 1 | 0.32% |
| Chandra Seetharaman | 2 | 0.01% | 1 | 0.32% |
| Benjamin Marzinski | 1 | 0.01% | 1 | 0.32% |
| Peter Zijlstra | 1 | 0.01% | 1 | 0.32% |
| Daniel Walker | 1 | 0.01% | 1 | 0.32% |
| Total | 13667 | 317 |
/* * 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; }; /* * 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; r = dm_uevent_init(); if (r) return r; 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(); return r; } static void local_exit(void) { flush_scheduled_work(); destroy_workqueue(deferred_remove_workqueue); 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_blk_report_zones(struct gendisk *disk, sector_t sector, struct blk_zone *zones, unsigned int *nr_zones, gfp_t gfp_mask) { #ifdef CONFIG_BLK_DEV_ZONED struct mapped_device *md = disk->private_data; struct dm_target *tgt; struct dm_table *map; int srcu_idx, ret; if (dm_suspended_md(md)) return -EAGAIN; map = dm_get_live_table(md, &srcu_idx); if (!map) return -EIO; tgt = dm_table_find_target(map, sector); if (!dm_target_is_valid(tgt)) { ret = -EIO; goto out; } /* * If we are executing this, we already know that the block device * is a zoned device and so each target should have support for that * type of drive. A missing report_zones method means that the target * driver has a problem. */ if (WARN_ON(!tgt->type->report_zones)) { ret = -EIO; goto out; } /* * blkdev_report_zones() will loop and call this again to cover all the * zones of the target, eventually moving on to the next target. * So there is no need to loop here trying to fill the entire array * of zones. */ ret = tgt->type->report_zones(tgt, sector, zones, nr_zones, gfp_mask); out: dm_put_live_table(md, srcu_idx); return ret; #else return -ENOTSUPP; #endif } 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); } static bool md_in_flight_bios(struct mapped_device *md) { int cpu; struct hd_struct *part = &dm_disk(md)->part0; long sum = 0; for_each_possible_cpu(cpu) { sum += part_stat_local_read_cpu(part, in_flight[0], cpu); sum += part_stat_local_read_cpu(part, in_flight[1], cpu); } return sum != 0; } static bool md_in_flight(struct mapped_device *md) { if (queue_is_mq(md->queue)) return blk_mq_queue_inflight(md->queue); else return md_in_flight_bios(md); } static void start_io_acct(struct dm_io *io) { struct mapped_device *md = io->md; struct bio *bio = io->orig_bio; io->start_time = jiffies; generic_start_io_acct(md->queue, bio_op(bio), bio_sectors(bio), &dm_disk(md)->part0); 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; generic_end_io_acct(md->queue, bio_op(bio), &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); /* nudge anyone waiting on suspend queue */ if (unlikely(wq_has_sleeper(&md->wait))) 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_discard(struct mapped_device *md) { struct queue_limits *limits = dm_get_queue_limits(md); /* device doesn't really support DISCARD, disable it */ limits->max_discard_sectors = 0; blk_queue_flag_clear(QUEUE_FLAG_DISCARD, md->queue); } 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_DISCARD && !bio->bi_disk->queue->limits.max_discard_sectors) disable_discard(md); else if (bio_op(bio) == REQ_OP_WRITE_SAME && !bio->bi_disk->queue->limits.max_write_same_sectors) disable_write_same(md); else 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; } ti->max_io_len = (uint32_t) len; 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); ret = ti->type->direct_access(ti, pgoff, nr_pages, kaddr, pfn); out: dm_put_live_table(md, srcu_idx); return ret; } static bool dm_dax_supported(struct dax_device *dax_dev, struct block_device *bdev, int blocksize, sector_t start, sector_t len) { struct mapped_device *md = dax_get_private(dax_dev); struct dm_table *map; int srcu_idx; bool ret; map = dm_get_live_table(md, &srcu_idx); if (!map) return false; ret = dm_table_supports_dax(map, blocksize); 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 underlying device of the target. The zone * descriptors must be remapped to match their position within the dm device. * The caller target should obtain the zones information using * blkdev_report_zones() to ensure that remapping for partition offset is * already handled. */ void dm_remap_zone_report(struct dm_target *ti, sector_t start, struct blk_zone *zones, unsigned int *nr_zones) { #ifdef CONFIG_BLK_DEV_ZONED struct blk_zone *zone; unsigned int nrz = *nr_zones; int i; /* * Remap the start sector and write pointer position of the zones in * the array. Since we may have obtained from the target underlying * device more zones that the target size, also adjust the number * of zones. */ for (i = 0; i < nrz; i++) { zone = zones + i; if (zone->start >= start + ti->len) { memset(zone, 0, sizeof(struct blk_zone) * (nrz - i)); break; } zone->start = zone->start + ti->begin - start; if (zone->type == BLK_ZONE_TYPE_CONVENTIONAL) continue; 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; } *nr_zones = i; #else /* !CONFIG_BLK_DEV_ZONED */ *nr_zones = 0; #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 (bio_integrity(bio)) { 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; } bio_advance(clone, to_bytes(sector - clone->bi_iter.bi_sector)); clone->bi_iter.bi_size = to_bytes(len); if (bio_integrity(bio)) 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; /* * Empty flush uses a statically initialized bio, as the base for * cloning. However, blkg association requires that a bdev is * associated with a gendisk, which doesn't happen until the bdev is * opened. So, blkg association is done at issue time of the flush * rather than when the device is created in alloc_dev(). */ bio_set_dev(ci->bio, ci->io->md->bdev); 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); bio_disassociate_blkg(ci->bio); 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; } static int __send_changing_extent_only(struct clone_info *ci, struct dm_target *ti, unsigned num_bios) { unsigned len; /* * 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. */ if (!num_bios) return -EOPNOTSUPP; len = min((sector_t)ci->sector_count, max_io_len_target_boundary(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(ti)); } 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(ti)); } 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(ti)); } 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(ti)); } static bool is_abnormal_io(struct bio *bio) { bool r = false; switch (bio_op(bio)) { case REQ_OP_DISCARD: case REQ_OP_SECURE_ERASE: case REQ_OP_WRITE_SAME: case REQ_OP_WRITE_ZEROES: r = true; break; } return r; } 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 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 (__process_abnormal_io(ci, ti, &r)) return r; 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; } #define __dm_part_stat_sub(part, field, subnd) \ (part_stat_get(part, field) -= (subnd)) /* * 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; init_clone_info(&ci, md, map, bio); if (bio->bi_opf & REQ_PREFLUSH) { struct bio flush_bio; /* * Use an on-stack bio for this, it's safe since we don't * need to reference it after submit. It's just used as * the basis for the clone(s). */ bio_init(&flush_bio, NULL, 0); flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; ci.bio = &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. */ struct bio *b = bio_split(bio, bio_sectors(bio) - ci.sector_count, GFP_NOIO, &md->queue->bio_split); ci.io->orig_bio = b; /* * Adjust IO stats for each split, otherwise upon queue * reentry there will be redundant IO accounting. * NOTE: this is a stop-gap fix, a proper fix involves * significant refactoring of DM core's bio splitting * (by eliminating DM's splitting and just using bio_split) */ part_stat_lock(); __dm_part_stat_sub(&dm_disk(md)->part0, sectors[op_stat_group(bio_op(bio))], ci.sector_count); part_stat_unlock(); bio_chain(b, bio); trace_block_split(md->queue, b, bio->bi_iter.bi_sector); 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 dm_target *ti) { struct clone_info ci; blk_qc_t ret = BLK_QC_T_NONE; int error = 0; init_clone_info(&ci, md, map, bio); if (bio->bi_opf & REQ_PREFLUSH) { struct bio flush_bio; /* * Use an on-stack bio for this, it's safe since we don't * need to reference it after submit. It's just used as * the basis for the clone(s). */ bio_init(&flush_bio, NULL, 0); flush_bio.bi_opf = REQ_OP_WRITE | REQ_PREFLUSH | REQ_SYNC; ci.bio = &flush_bio; ci.sector_count = 0; error = __send_empty_flush(&ci); /* dec_pending submits any data associated with flush */ } else { struct dm_target_io *tio; ci.bio = bio; ci.sector_count = bio_sectors(bio); if (__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; } static void dm_queue_split(struct mapped_device *md, struct dm_target *ti, struct bio **bio) { unsigned len, sector_count; sector_count = bio_sectors(*bio); len = min_t(sector_t, max_io_len((*bio)->bi_iter.bi_sector, ti), sector_count); if (sector_count > len) { struct bio *split = bio_split(*bio, len, GFP_NOIO, &md->queue->bio_split); bio_chain(split, *bio); trace_block_split(md->queue, split, (*bio)->bi_iter.bi_sector); generic_make_request(*bio); *bio = split; } } static blk_qc_t dm_process_bio(struct mapped_device *md, struct dm_table *map, struct bio *bio) { blk_qc_t ret = BLK_QC_T_NONE; struct dm_target *ti = md->immutable_target; if (unlikely(!map)) { bio_io_error(bio); return ret; } if (!ti) { ti = dm_table_find_target(map, bio->bi_iter.bi_sector); if (unlikely(!ti || !dm_target_is_valid(ti))) { bio_io_error(bio); return ret; } } /* * If in ->make_request_fn we need to use blk_queue_split(), otherwise * queue_limits for abnormal requests (e.g. discard, writesame, etc) * won't be imposed. */ if (current->bio_list) { blk_queue_split(md->queue, &bio); if (!is_abnormal_io(bio)) dm_queue_split(md, ti, &bio); } if (dm_get_md_type(md) == DM_TYPE_NVME_BIO_BASED) return __process_bio(md, map, bio, ti); else return __split_and_process_bio(md, map, bio); } static blk_qc_t dm_make_request(struct request_queue *q, struct bio *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 = dm_process_bio(md, map, bio); dm_put_live_table(md, srcu_idx); return ret; } 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) { /* * 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); 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 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->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); 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; init_waitqueue_head(&md->wait); INIT_WORK(&md->work, dm_wq_work); init_waitqueue_head(&md->eventq); init_completion(&md->kobj_holder.completion); 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)) { md->dax_dev = alloc_dax(md, md->disk->disk_name, &dm_dax_ops); if (!md->dax_dev) goto bad; } 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; 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: 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: case DM_TYPE_NVME_BIO_BASED: dm_init_normal_md_queue(md); blk_queue_make_request(md->queue, dm_make_request); 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); /* * 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)) (void) generic_make_request(c); else (void) dm_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); 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: 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, .report_zones = dm_blk_report_zones, .pr_ops = &dm_pr_ops, .owner = THIS_MODULE }; static const struct dax_operations dm_dax_ops = { .direct_access = dm_dax_direct_access, .dax_supported = dm_dax_supported, .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");
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