/*
* Work processed by per-device workqueue.
*/
-struct dm_wq_req {
- enum {
- DM_WQ_FLUSH_DEFERRED,
- } type;
- struct work_struct work;
- struct mapped_device *md;
- void *context;
-};
-
struct mapped_device {
struct rw_semaphore io_lock;
struct mutex suspend_lock;
- spinlock_t pushback_lock;
rwlock_t map_lock;
atomic_t holders;
atomic_t open_count;
*/
atomic_t pending;
wait_queue_head_t wait;
+ struct work_struct work;
struct bio_list deferred;
- struct bio_list pushback;
+ spinlock_t deferred_lock;
/*
* Processing queue (flush/barriers)
return 1;
}
+ spin_lock_irq(&md->deferred_lock);
bio_list_add(&md->deferred, bio);
+ spin_unlock_irq(&md->deferred_lock);
up_write(&md->io_lock);
return 0; /* deferred successfully */
if (io->error == DM_ENDIO_REQUEUE) {
/*
* Target requested pushing back the I/O.
- * This must be handled before the sleeper on
- * suspend queue merges the pushback list.
*/
- spin_lock_irqsave(&md->pushback_lock, flags);
+ spin_lock_irqsave(&md->deferred_lock, flags);
if (__noflush_suspending(md))
- bio_list_add(&md->pushback, io->bio);
+ bio_list_add(&md->deferred, io->bio);
else
/* noflush suspend was interrupted. */
io->error = -EIO;
- spin_unlock_irqrestore(&md->pushback_lock, flags);
+ spin_unlock_irqrestore(&md->deferred_lock, flags);
}
end_io_acct(io);
}
/*
- * Split the bio into several clones.
+ * Split the bio into several clones and submit it to targets.
*/
-static int __split_bio(struct mapped_device *md, struct bio *bio)
+static void __split_and_process_bio(struct mapped_device *md, struct bio *bio)
{
struct clone_info ci;
int error = 0;
ci.map = dm_get_table(md);
- if (unlikely(!ci.map))
- return -EIO;
+ if (unlikely(!ci.map)) {
+ bio_io_error(bio);
+ return;
+ }
if (unlikely(bio_barrier(bio) && !dm_table_barrier_ok(ci.map))) {
dm_table_put(ci.map);
bio_endio(bio, -EOPNOTSUPP);
- return 0;
+ return;
}
ci.md = md;
ci.bio = bio;
/* drop the extra reference count */
dec_pending(ci.io, error);
dm_table_put(ci.map);
-
- return 0;
}
/*-----------------------------------------------------------------
* CRUD END
down_read(&md->io_lock);
}
- r = __split_bio(md, bio);
+ __split_and_process_bio(md, bio);
up_read(&md->io_lock);
+ return 0;
out_req:
if (r < 0)
static struct block_device_operations dm_blk_dops;
+static void dm_wq_work(struct work_struct *work);
+
/*
* Allocate and initialise a blank device with a given minor.
*/
init_rwsem(&md->io_lock);
mutex_init(&md->suspend_lock);
- spin_lock_init(&md->pushback_lock);
+ spin_lock_init(&md->deferred_lock);
rwlock_init(&md->map_lock);
atomic_set(&md->holders, 1);
atomic_set(&md->open_count, 0);
md->queue->backing_dev_info.congested_fn = dm_any_congested;
md->queue->backing_dev_info.congested_data = md;
blk_queue_make_request(md->queue, dm_request);
+ blk_queue_ordered(md->queue, QUEUE_ORDERED_DRAIN, NULL);
blk_queue_bounce_limit(md->queue, BLK_BOUNCE_ANY);
md->queue->unplug_fn = dm_unplug_all;
blk_queue_merge_bvec(md->queue, dm_merge_bvec);
atomic_set(&md->pending, 0);
init_waitqueue_head(&md->wait);
+ INIT_WORK(&md->work, dm_wq_work);
init_waitqueue_head(&md->eventq);
md->disk->major = _major;
}
EXPORT_SYMBOL_GPL(dm_put);
-static int dm_wait_for_completion(struct mapped_device *md)
+static int dm_wait_for_completion(struct mapped_device *md, int interruptible)
{
int r = 0;
+ DECLARE_WAITQUEUE(wait, current);
+
+ dm_unplug_all(md->queue);
+
+ add_wait_queue(&md->wait, &wait);
while (1) {
- set_current_state(TASK_INTERRUPTIBLE);
+ set_current_state(interruptible);
smp_mb();
if (!atomic_read(&md->pending))
break;
- if (signal_pending(current)) {
+ if (interruptible == TASK_INTERRUPTIBLE &&
+ signal_pending(current)) {
r = -EINTR;
break;
}
}
set_current_state(TASK_RUNNING);
+ remove_wait_queue(&md->wait, &wait);
+
return r;
}
/*
* Process the deferred bios
*/
-static void __flush_deferred_io(struct mapped_device *md)
+static void dm_wq_work(struct work_struct *work)
{
+ struct mapped_device *md = container_of(work, struct mapped_device,
+ work);
struct bio *c;
- while ((c = bio_list_pop(&md->deferred))) {
- if (__split_bio(md, c))
- bio_io_error(c);
- }
-
- clear_bit(DMF_BLOCK_IO, &md->flags);
-}
+ down_write(&md->io_lock);
-static void __merge_pushback_list(struct mapped_device *md)
-{
- unsigned long flags;
+next_bio:
+ spin_lock_irq(&md->deferred_lock);
+ c = bio_list_pop(&md->deferred);
+ spin_unlock_irq(&md->deferred_lock);
- spin_lock_irqsave(&md->pushback_lock, flags);
- clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
- bio_list_merge_head(&md->deferred, &md->pushback);
- bio_list_init(&md->pushback);
- spin_unlock_irqrestore(&md->pushback_lock, flags);
-}
+ if (c) {
+ __split_and_process_bio(md, c);
+ goto next_bio;
+ }
-static void dm_wq_work(struct work_struct *work)
-{
- struct dm_wq_req *req = container_of(work, struct dm_wq_req, work);
- struct mapped_device *md = req->md;
+ clear_bit(DMF_BLOCK_IO, &md->flags);
- down_write(&md->io_lock);
- switch (req->type) {
- case DM_WQ_FLUSH_DEFERRED:
- __flush_deferred_io(md);
- break;
- default:
- DMERR("dm_wq_work: unrecognised work type %d", req->type);
- BUG();
- }
up_write(&md->io_lock);
}
-static void dm_wq_queue(struct mapped_device *md, int type, void *context,
- struct dm_wq_req *req)
-{
- req->type = type;
- req->md = md;
- req->context = context;
- INIT_WORK(&req->work, dm_wq_work);
- queue_work(md->wq, &req->work);
-}
-
-static void dm_queue_flush(struct mapped_device *md, int type, void *context)
+static void dm_queue_flush(struct mapped_device *md)
{
- struct dm_wq_req req;
-
- dm_wq_queue(md, type, context, &req);
+ queue_work(md->wq, &md->work);
flush_workqueue(md->wq);
}
int dm_suspend(struct mapped_device *md, unsigned suspend_flags)
{
struct dm_table *map = NULL;
- DECLARE_WAITQUEUE(wait, current);
int r = 0;
int do_lockfs = suspend_flags & DM_SUSPEND_LOCKFS_FLAG ? 1 : 0;
int noflush = suspend_flags & DM_SUSPEND_NOFLUSH_FLAG ? 1 : 0;
down_write(&md->io_lock);
set_bit(DMF_BLOCK_IO, &md->flags);
- add_wait_queue(&md->wait, &wait);
up_write(&md->io_lock);
- /* unplug */
- if (map)
- dm_table_unplug_all(map);
-
/*
* Wait for the already-mapped ios to complete.
*/
- r = dm_wait_for_completion(md);
+ r = dm_wait_for_completion(md, TASK_INTERRUPTIBLE);
down_write(&md->io_lock);
- remove_wait_queue(&md->wait, &wait);
if (noflush)
- __merge_pushback_list(md);
+ clear_bit(DMF_NOFLUSH_SUSPENDING, &md->flags);
up_write(&md->io_lock);
/* were we interrupted ? */
if (r < 0) {
- dm_queue_flush(md, DM_WQ_FLUSH_DEFERRED, NULL);
+ dm_queue_flush(md);
unlock_fs(md);
goto out; /* pushback list is already flushed, so skip flush */
if (r)
goto out;
- dm_queue_flush(md, DM_WQ_FLUSH_DEFERRED, NULL);
+ dm_queue_flush(md);
unlock_fs(md);
git.samba.org / sfrench / cifs-2.6.git / blobdiff