#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;
* freeze/thaw support require holding onto a super block
*/
struct super_block *frozen_sb;
- struct block_device *suspended_bdev;
+ struct block_device *bdev;
/* forced geometry settings */
struct hd_geometry geometry;
/* sysfs handle */
struct kobject kobj;
+
+ /* zero-length barrier that will be cloned and submitted to targets */
+ struct bio barrier_bio;
};
#define MIN_IOS 256
mempool_free(io, md->io_pool);
}
-static struct dm_target_io *alloc_tio(struct mapped_device *md)
-{
- return mempool_alloc(md->tio_pool, GFP_NOIO);
-}
-
static void free_tio(struct mapped_device *md, struct dm_target_io *tio)
{
mempool_free(tio, md->tio_pool);
* Target requested pushing back the I/O.
*/
spin_lock_irqsave(&md->deferred_lock, flags);
- if (__noflush_suspending(md))
- bio_list_add_head(&md->deferred, io->bio);
- else
+ if (__noflush_suspending(md)) {
+ if (!bio_barrier(io->bio))
+ bio_list_add_head(&md->deferred,
+ io->bio);
+ } else
/* noflush suspend was interrupted. */
io->error = -EIO;
spin_unlock_irqrestore(&md->deferred_lock, flags);
* a per-device variable for error reporting.
* Note that you can't touch the bio after end_io_acct
*/
- md->barrier_error = io_error;
+ if (!md->barrier_error && io_error != -EOPNOTSUPP)
+ md->barrier_error = io_error;
end_io_acct(io);
} else {
end_io_acct(io);
sector_t sector;
struct mapped_device *md;
- /*
- * Sanity checks.
- */
- BUG_ON(!clone->bi_size);
-
clone->bi_end_io = clone_endio;
clone->bi_private = tio;
return clone;
}
+static struct dm_target_io *alloc_tio(struct clone_info *ci,
+ struct dm_target *ti)
+{
+ struct dm_target_io *tio = mempool_alloc(ci->md->tio_pool, GFP_NOIO);
+
+ tio->io = ci->io;
+ tio->ti = ti;
+ memset(&tio->info, 0, sizeof(tio->info));
+
+ return tio;
+}
+
+static void __flush_target(struct clone_info *ci, struct dm_target *ti,
+ unsigned flush_nr)
+{
+ struct dm_target_io *tio = alloc_tio(ci, ti);
+ struct bio *clone;
+
+ tio->info.flush_request = flush_nr;
+
+ clone = bio_alloc_bioset(GFP_NOIO, 0, ci->md->bs);
+ __bio_clone(clone, ci->bio);
+ clone->bi_destructor = dm_bio_destructor;
+
+ __map_bio(ti, clone, tio);
+}
+
+static int __clone_and_map_empty_barrier(struct clone_info *ci)
+{
+ unsigned target_nr = 0, flush_nr;
+ struct dm_target *ti;
+
+ while ((ti = dm_table_get_target(ci->map, target_nr++)))
+ for (flush_nr = 0; flush_nr < ti->num_flush_requests;
+ flush_nr++)
+ __flush_target(ci, ti, flush_nr);
+
+ ci->sector_count = 0;
+
+ return 0;
+}
+
static int __clone_and_map(struct clone_info *ci)
{
struct bio *clone, *bio = ci->bio;
sector_t len = 0, max;
struct dm_target_io *tio;
+ if (unlikely(bio_empty_barrier(bio)))
+ return __clone_and_map_empty_barrier(ci);
+
ti = dm_table_find_target(ci->map, ci->sector);
if (!dm_target_is_valid(ti))
return -EIO;
/*
* Allocate a target io object.
*/
- tio = alloc_tio(ci->md);
- tio->io = ci->io;
- tio->ti = ti;
- memset(&tio->info, 0, sizeof(tio->info));
+ tio = alloc_tio(ci, ti);
if (ci->sector_count <= max) {
/*
max = max_io_len(ci->md, ci->sector, ti);
- tio = alloc_tio(ci->md);
- tio->io = ci->io;
- tio->ti = ti;
- memset(&tio->info, 0, sizeof(tio->info));
+ tio = alloc_tio(ci, ti);
}
len = min(remaining, max);
if (!bio_barrier(bio))
bio_io_error(bio);
else
- md->barrier_error = -EIO;
+ if (!md->barrier_error)
+ md->barrier_error = -EIO;
return;
}
ci.io->md = md;
ci.sector = bio->bi_sector;
ci.sector_count = bio_sectors(bio);
+ if (unlikely(bio_empty_barrier(bio)))
+ ci.sector_count = 1;
ci.idx = bio->bi_idx;
start_io_acct(ci.io);
*/
if (max_size && ti->type->merge)
max_size = ti->type->merge(ti, bvm, biovec, max_size);
+ /*
+ * If the target doesn't support merge method and some of the devices
+ * provided their merge_bvec method (we know this by looking at
+ * queue_max_hw_sectors), then we can't allow bios with multiple vector
+ * entries. So always set max_size to 0, and the code below allows
+ * just one page.
+ */
+ else if (queue_max_hw_sectors(q) <= PAGE_SIZE >> 9)
+
+ max_size = 0;
out_table:
dm_table_put(map);
if (!md->wq)
goto bad_thread;
+ md->bdev = bdget_disk(md->disk, 0);
+ if (!md->bdev)
+ goto bad_bdev;
+
/* Populate the mapping, nobody knows we exist yet */
spin_lock(&_minor_lock);
old_md = idr_replace(&_minor_idr, md, minor);
return md;
+bad_bdev:
+ destroy_workqueue(md->wq);
bad_thread:
put_disk(md->disk);
bad_disk:
{
int minor = MINOR(disk_devt(md->disk));
- if (md->suspended_bdev) {
- unlock_fs(md);
- bdput(md->suspended_bdev);
- }
+ unlock_fs(md);
+ bdput(md->bdev);
destroy_workqueue(md->wq);
mempool_destroy(md->tio_pool);
mempool_destroy(md->io_pool);
{
set_capacity(md->disk, size);
- mutex_lock(&md->suspended_bdev->bd_inode->i_mutex);
- i_size_write(md->suspended_bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
- mutex_unlock(&md->suspended_bdev->bd_inode->i_mutex);
+ mutex_lock(&md->bdev->bd_inode->i_mutex);
+ i_size_write(md->bdev->bd_inode, (loff_t)size << SECTOR_SHIFT);
+ mutex_unlock(&md->bdev->bd_inode->i_mutex);
}
-static int __bind(struct mapped_device *md, struct dm_table *t)
+static int __bind(struct mapped_device *md, struct dm_table *t,
+ struct queue_limits *limits)
{
struct request_queue *q = md->queue;
sector_t size;
if (size != get_capacity(md->disk))
memset(&md->geometry, 0, sizeof(md->geometry));
- if (md->suspended_bdev)
- __set_size(md, size);
+ __set_size(md, size);
if (!size) {
dm_table_destroy(t);
write_lock(&md->map_lock);
md->map = t;
- dm_table_set_restrictions(t, q);
+ dm_table_set_restrictions(t, q, limits);
write_unlock(&md->map_lock);
return 0;
return r;
}
-static int dm_flush(struct mapped_device *md)
+static void dm_flush(struct mapped_device *md)
{
dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE);
- return 0;
+
+ bio_init(&md->barrier_bio);
+ md->barrier_bio.bi_bdev = md->bdev;
+ md->barrier_bio.bi_rw = WRITE_BARRIER;
+ __split_and_process_bio(md, &md->barrier_bio);
+
+ dm_wait_for_completion(md, TASK_UNINTERRUPTIBLE);
}
static void process_barrier(struct mapped_device *md, struct bio *bio)
{
- int error = dm_flush(md);
-
- if (unlikely(error)) {
- bio_endio(bio, error);
- return;
- }
- if (bio_empty_barrier(bio)) {
- bio_endio(bio, 0);
- return;
- }
-
- __split_and_process_bio(md, bio);
+ md->barrier_error = 0;
- error = dm_flush(md);
+ dm_flush(md);
- if (!error && md->barrier_error)
- error = md->barrier_error;
+ if (!bio_empty_barrier(bio)) {
+ __split_and_process_bio(md, bio);
+ dm_flush(md);
+ }
if (md->barrier_error != DM_ENDIO_REQUEUE)
- bio_endio(bio, error);
+ bio_endio(bio, md->barrier_error);
+ else {
+ spin_lock_irq(&md->deferred_lock);
+ bio_list_add_head(&md->deferred, bio);
+ spin_unlock_irq(&md->deferred_lock);
+ }
}
/*
*/
int dm_swap_table(struct mapped_device *md, struct dm_table *table)
{
+ struct queue_limits limits;
int r = -EINVAL;
mutex_lock(&md->suspend_lock);
if (!dm_suspended(md))
goto out;
- /* without bdev, the device size cannot be changed */
- if (!md->suspended_bdev)
- if (get_capacity(md->disk) != dm_table_get_size(table))
- goto out;
+ r = dm_calculate_queue_limits(table, &limits);
+ if (r)
+ goto out;
__unbind(md);
- r = __bind(md, table);
+ r = __bind(md, table, &limits);
out:
mutex_unlock(&md->suspend_lock);
WARN_ON(md->frozen_sb);
- md->frozen_sb = freeze_bdev(md->suspended_bdev);
+ md->frozen_sb = freeze_bdev(md->bdev);
if (IS_ERR(md->frozen_sb)) {
r = PTR_ERR(md->frozen_sb);
md->frozen_sb = NULL;
set_bit(DMF_FROZEN, &md->flags);
- /* don't bdput right now, we don't want the bdev
- * to go away while it is locked.
- */
return 0;
}
if (!test_bit(DMF_FROZEN, &md->flags))
return;
- thaw_bdev(md->suspended_bdev, md->frozen_sb);
+ thaw_bdev(md->bdev, md->frozen_sb);
md->frozen_sb = NULL;
clear_bit(DMF_FROZEN, &md->flags);
}
/* This does not get reverted if there's an error later. */
dm_table_presuspend_targets(map);
- /* bdget() can stall if the pending I/Os are not flushed */
- if (!noflush) {
- md->suspended_bdev = bdget_disk(md->disk, 0);
- if (!md->suspended_bdev) {
- DMWARN("bdget failed in dm_suspend");
- r = -ENOMEM;
+ /*
+ * Flush I/O to the device. noflush supersedes do_lockfs,
+ * because lock_fs() needs to flush I/Os.
+ */
+ if (!noflush && do_lockfs) {
+ r = lock_fs(md);
+ if (r)
goto out;
- }
-
- /*
- * Flush I/O to the device. noflush supersedes do_lockfs,
- * because lock_fs() needs to flush I/Os.
- */
- if (do_lockfs) {
- r = lock_fs(md);
- if (r)
- goto out;
- }
}
/*
set_bit(DMF_SUSPENDED, &md->flags);
out:
- if (r && md->suspended_bdev) {
- bdput(md->suspended_bdev);
- md->suspended_bdev = NULL;
- }
-
dm_table_put(map);
out_unlock:
unlock_fs(md);
- if (md->suspended_bdev) {
- bdput(md->suspended_bdev);
- md->suspended_bdev = NULL;
- }
-
clear_bit(DMF_SUSPENDED, &md->flags);
dm_table_unplug_all(map);
-
- dm_kobject_uevent(md);
-
r = 0;
-
out:
dm_table_put(map);
mutex_unlock(&md->suspend_lock);
/*-----------------------------------------------------------------
* Event notification.
*---------------------------------------------------------------*/
-void dm_kobject_uevent(struct mapped_device *md)
-{
- kobject_uevent(&disk_to_dev(md->disk)->kobj, KOBJ_CHANGE);
+void 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)
+ kobject_uevent(&disk_to_dev(md->disk)->kobj, action);
+ else {
+ snprintf(udev_cookie, DM_COOKIE_LENGTH, "%s=%u",
+ DM_COOKIE_ENV_VAR_NAME, cookie);
+ kobject_uevent_env(&disk_to_dev(md->disk)->kobj, action, envp);
+ }
}
uint32_t dm_next_uevent_seq(struct mapped_device *md)
if (&md->kobj != kobj)
return NULL;
+ if (test_bit(DMF_FREEING, &md->flags) ||
+ test_bit(DMF_DELETING, &md->flags))
+ return NULL;
+
dm_get(md);
return md;
}
git://bbs.cooldavid.org / net-next-2.6.git / blobdiff