Merge git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm

* git://git.kernel.org/pub/scm/linux/kernel/git/agk/linux-2.6-dm:
  dm snapshot: allow chunk size to be less than page size
  dm snapshot: use unsigned integer chunk size
  dm snapshot: lock snapshot while supplying status
  dm exception store: fix failed set_chunk_size error path
  dm snapshot: require non zero chunk size by end of ctr
  dm: dec_pending needs locking to save error value
  dm: add missing del_gendisk to alloc_dev error path
  dm log: userspace fix incorrect luid cast in userspace_ctr
  dm snapshot: free exception store on init failure
  dm snapshot: sort by chunk size to fix race

drivers/md/dm-exception-store.c

@@ -138,24 +138,15 @@ int dm_exception_store_type_unregister(struct dm_exception_store_type *type)
 }
 EXPORT_SYMBOL(dm_exception_store_type_unregister);
 
-/*
- * Round a number up to the nearest 'size' boundary.  size must
- * be a power of 2.
- */
-static ulong round_up(ulong n, ulong size)
-{
-	size--;
-	return (n + size) & ~size;
-}
-
 static int set_chunk_size(struct dm_exception_store *store,
 			  const char *chunk_size_arg, char **error)
 {
 	unsigned long chunk_size_ulong;
 	char *value;
 
 	chunk_size_ulong = simple_strtoul(chunk_size_arg, &value, 10);
-	if (*chunk_size_arg == '\0' || *value != '\0') {
+	if (*chunk_size_arg == '\0' || *value != '\0' ||
+	    chunk_size_ulong > UINT_MAX) {
 		*error = "Invalid chunk size";
 		return -EINVAL;
 	}
@@ -165,40 +156,35 @@ static int set_chunk_size(struct dm_exception_store *store,
 		return 0;
 	}
 
-	/*
-	 * Chunk size must be multiple of page size.  Silently
-	 * round up if it's not.
-	 */
-	chunk_size_ulong = round_up(chunk_size_ulong, PAGE_SIZE >> 9);
-
-	return dm_exception_store_set_chunk_size(store, chunk_size_ulong,
+	return dm_exception_store_set_chunk_size(store,
+						 (unsigned) chunk_size_ulong,
 						 error);
 }
 
 int dm_exception_store_set_chunk_size(struct dm_exception_store *store,
-				      unsigned long chunk_size_ulong,
+				      unsigned chunk_size,
 				      char **error)
 {
 	/* Check chunk_size is a power of 2 */
-	if (!is_power_of_2(chunk_size_ulong)) {
+	if (!is_power_of_2(chunk_size)) {
 		*error = "Chunk size is not a power of 2";
 		return -EINVAL;
 	}
 
 	/* Validate the chunk size against the device block size */
-	if (chunk_size_ulong % (bdev_logical_block_size(store->cow->bdev) >> 9)) {
+	if (chunk_size % (bdev_logical_block_size(store->cow->bdev) >> 9)) {
 		*error = "Chunk size is not a multiple of device blocksize";
 		return -EINVAL;
 	}
 
-	if (chunk_size_ulong > INT_MAX >> SECTOR_SHIFT) {
+	if (chunk_size > INT_MAX >> SECTOR_SHIFT) {
 		*error = "Chunk size is too high";
 		return -EINVAL;
 	}
 
-	store->chunk_size = chunk_size_ulong;
-	store->chunk_mask = chunk_size_ulong - 1;
-	store->chunk_shift = ffs(chunk_size_ulong) - 1;
+	store->chunk_size = chunk_size;
+	store->chunk_mask = chunk_size - 1;
+	store->chunk_shift = ffs(chunk_size) - 1;
 
 	return 0;
 }
@@ -251,7 +237,7 @@ int dm_exception_store_create(struct dm_target *ti, int argc, char **argv,
 
 	r = set_chunk_size(tmp_store, argv[2], &ti->error);
 	if (r)
-		goto bad_cow;
+		goto bad_ctr;
 
 	r = type->ctr(tmp_store, 0, NULL);
 	if (r) {

drivers/md/dm-exception-store.h

@@ -101,9 +101,9 @@ struct dm_exception_store {
 	struct dm_dev *cow;
 
 	/* Size of data blocks saved - must be a power of 2 */
-	chunk_t chunk_size;
-	chunk_t chunk_mask;
-	chunk_t chunk_shift;
+	unsigned chunk_size;
+	unsigned chunk_mask;
+	unsigned chunk_shift;
 
 	void *context;
 };
@@ -169,7 +169,7 @@ int dm_exception_store_type_register(struct dm_exception_store_type *type);
 int dm_exception_store_type_unregister(struct dm_exception_store_type *type);
 
 int dm_exception_store_set_chunk_size(struct dm_exception_store *store,
-				      unsigned long chunk_size_ulong,
+				      unsigned chunk_size,
 				      char **error);
 
 int dm_exception_store_create(struct dm_target *ti, int argc, char **argv,

drivers/md/dm-log-userspace-base.c

@@ -156,7 +156,7 @@ static int userspace_ctr(struct dm_dirty_log *log, struct dm_target *ti,
 	}
 
 	/* The ptr value is sufficient for local unique id */
-	lc->luid = (uint64_t)lc;
+	lc->luid = (unsigned long)lc;
 
 	lc->ti = ti;
 

drivers/md/dm-snap-persistent.c

@@ -284,12 +284,13 @@ static int read_header(struct pstore *ps, int *new_snapshot)
 {
 	int r;
 	struct disk_header *dh;
-	chunk_t chunk_size;
+	unsigned chunk_size;
 	int chunk_size_supplied = 1;
 	char *chunk_err;
 
 	/*
-	 * Use default chunk size (or hardsect_size, if larger) if none supplied
+	 * Use default chunk size (or logical_block_size, if larger)
+	 * if none supplied
 	 */
 	if (!ps->store->chunk_size) {
 		ps->store->chunk_size = max(DM_CHUNK_SIZE_DEFAULT_SECTORS,
@@ -334,19 +335,18 @@ static int read_header(struct pstore *ps, int *new_snapshot)
 		return 0;
 
 	if (chunk_size_supplied)
-		DMWARN("chunk size %llu in device metadata overrides "
-		       "table chunk size of %llu.",
-		       (unsigned long long)chunk_size,
-		       (unsigned long long)ps->store->chunk_size);
+		DMWARN("chunk size %u in device metadata overrides "
+		       "table chunk size of %u.",
+		       chunk_size, ps->store->chunk_size);
 
 	/* We had a bogus chunk_size. Fix stuff up. */
 	free_area(ps);
 
 	r = dm_exception_store_set_chunk_size(ps->store, chunk_size,
 					      &chunk_err);
 	if (r) {
-		DMERR("invalid on-disk chunk size %llu: %s.",
-		      (unsigned long long)chunk_size, chunk_err);
+		DMERR("invalid on-disk chunk size %u: %s.",
+		      chunk_size, chunk_err);
 		return r;
 	}
 

drivers/md/dm-snap.c

@@ -296,6 +296,7 @@ static void __insert_origin(struct origin *o)
  */
 static int register_snapshot(struct dm_snapshot *snap)
 {
+	struct dm_snapshot *l;
 	struct origin *o, *new_o;
 	struct block_device *bdev = snap->origin->bdev;
 
@@ -319,7 +320,11 @@ static int register_snapshot(struct dm_snapshot *snap)
 		__insert_origin(o);
 	}
 
-	list_add_tail(&snap->list, &o->snapshots);
+	/* Sort the list according to chunk size, largest-first smallest-last */
+	list_for_each_entry(l, &o->snapshots, list)
+		if (l->store->chunk_size < snap->store->chunk_size)
+			break;
+	list_add_tail(&snap->list, &l->list);
 
 	up_write(&_origins_lock);
 	return 0;
@@ -668,6 +673,11 @@ static int snapshot_ctr(struct dm_target *ti, unsigned int argc, char **argv)
 	bio_list_init(&s->queued_bios);
 	INIT_WORK(&s->queued_bios_work, flush_queued_bios);
 
+	if (!s->store->chunk_size) {
+		ti->error = "Chunk size not set";
+		goto bad_load_and_register;
+	}
+
 	/* Add snapshot to the list of snapshots for this origin */
 	/* Exceptions aren't triggered till snapshot_resume() is called */
 	if (register_snapshot(s)) {
@@ -951,7 +961,7 @@ static void start_copy(struct dm_snap_pending_exception *pe)
 
 	src.bdev = bdev;
 	src.sector = chunk_to_sector(s->store, pe->e.old_chunk);
-	src.count = min(s->store->chunk_size, dev_size - src.sector);
+	src.count = min((sector_t)s->store->chunk_size, dev_size - src.sector);
 
 	dest.bdev = s->store->cow->bdev;
 	dest.sector = chunk_to_sector(s->store, pe->e.new_chunk);
@@ -1142,6 +1152,8 @@ static int snapshot_status(struct dm_target *ti, status_type_t type,
 	unsigned sz = 0;
 	struct dm_snapshot *snap = ti->private;
 
+	down_write(&snap->lock);
+
 	switch (type) {
 	case STATUSTYPE_INFO:
 		if (!snap->valid)
@@ -1173,6 +1185,8 @@ static int snapshot_status(struct dm_target *ti, status_type_t type,
 		break;
 	}
 
+	up_write(&snap->lock);
+
 	return 0;
 }
 
@@ -1388,7 +1402,7 @@ static void origin_resume(struct dm_target *ti)
 	struct dm_dev *dev = ti->private;
 	struct dm_snapshot *snap;
 	struct origin *o;
-	chunk_t chunk_size = 0;
+	unsigned chunk_size = 0;
 
 	down_read(&_origins_lock);
 	o = __lookup_origin(dev->bdev);
@@ -1465,7 +1479,7 @@ static int __init dm_snapshot_init(void)
 	r = dm_register_target(&snapshot_target);
 	if (r) {
 		DMERR("snapshot target register failed %d", r);
-		return r;
+		goto bad_register_snapshot_target;
 	}
 
 	r = dm_register_target(&origin_target);
@@ -1522,6 +1536,9 @@ static int __init dm_snapshot_init(void)
 	dm_unregister_target(&origin_target);
 bad1:
 	dm_unregister_target(&snapshot_target);
+
+bad_register_snapshot_target:
+	dm_exception_store_exit();
 	return r;
 }
 

drivers/md/dm.c

@@ -47,6 +47,7 @@ struct dm_io {
 	atomic_t io_count;
 	struct bio *bio;
 	unsigned long start_time;
+	spinlock_t endio_lock;
 };
 
 /*
@@ -578,8 +579,12 @@ static void dec_pending(struct dm_io *io, int error)
 	struct mapped_device *md = io->md;
 
 	/* Push-back supersedes any I/O errors */
-	if (error && !(io->error > 0 && __noflush_suspending(md)))
-		io->error = error;
+	if (unlikely(error)) {
+		spin_lock_irqsave(&io->endio_lock, flags);
+		if (!(io->error > 0 && __noflush_suspending(md)))
+			io->error = error;
+		spin_unlock_irqrestore(&io->endio_lock, flags);
+	}
 
 	if (atomic_dec_and_test(&io->io_count)) {
 		if (io->error == DM_ENDIO_REQUEUE) {
@@ -1226,6 +1231,7 @@ static void __split_and_process_bio(struct mapped_device *md, struct bio *bio)
 	atomic_set(&ci.io->io_count, 1);
 	ci.io->bio = bio;
 	ci.io->md = md;
+	spin_lock_init(&ci.io->endio_lock);
 	ci.sector = bio->bi_sector;
 	ci.sector_count = bio_sectors(bio);
 	if (unlikely(bio_empty_barrier(bio)))
@@ -1822,6 +1828,7 @@ static struct mapped_device *alloc_dev(int minor)
 bad_bdev:
 	destroy_workqueue(md->wq);
 bad_thread:
+	del_gendisk(md->disk);
 	put_disk(md->disk);
 bad_disk:
 	blk_cleanup_queue(md->queue);