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

6 files changed, 55 insertions, 45 deletions

diff --git a/drivers/md/dm-exception-store.c b/drivers/md/dm-exception-store.c
index 556acff3952f..7dbe652efb5a 100644
--- a/drivers/md/dm-exception-store.c
+++ b/drivers/md/dm-exception-store.c
@@ -138,16 +138,6 @@ 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)
 {
@@ -155,7 +145,8 @@ static int set_chunk_size(struct dm_exception_store *store,
         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) {
diff --git a/drivers/md/dm-exception-store.h b/drivers/md/dm-exception-store.h
index 812c71872ba0..8a223a48802c 100644
--- a/drivers/md/dm-exception-store.h
+++ b/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,
diff --git a/drivers/md/dm-log-userspace-base.c b/drivers/md/dm-log-userspace-base.c
index 652bd33109e3..7ac2c1450d10 100644
--- a/drivers/md/dm-log-userspace-base.c
+++ b/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;
 
diff --git a/drivers/md/dm-snap-persistent.c b/drivers/md/dm-snap-persistent.c
index d5b2e08750d5..0c746420c008 100644
--- a/drivers/md/dm-snap-persistent.c
+++ b/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,
@@ -334,10 +335,9 @@ 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);
@@ -345,8 +345,8 @@ static int read_header(struct pstore *ps, int *new_snapshot)
         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;
         }
 
diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 57f1bf7f3b7a..3a3ba46e6d4b 100644
--- a/drivers/md/dm-snap.c
+++ b/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 @@ bad2:
         dm_unregister_target(&origin_target);
 bad1:
         dm_unregister_target(&snapshot_target);
+
+bad_register_snapshot_target:
+        dm_exception_store_exit();
         return r;
 }
 
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 376f1ab48a24..724efc63904d 100644
--- a/drivers/md/dm.c
+++ b/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);