Merge branch 'acpica' into release

24 files changed, 530 insertions, 100 deletions

diff --git a/fs/afs/write.c b/fs/afs/write.c
index 15690bb..789b3af 100644
--- a/fs/afs/write.c
+++ b/fs/afs/write.c
@@ -140,6 +140,7 @@ int afs_write_begin(struct file *file, struct address_space *mapping,
 	candidate->first = candidate->last = index;
 	candidate->offset_first = from;
 	candidate->to_last = to;
+	INIT_LIST_HEAD(&candidate->link);
 	candidate->usage = 1;
 	candidate->state = AFS_WBACK_PENDING;
 	init_waitqueue_head(&candidate->waitq);
diff --git a/fs/aio.c b/fs/aio.c
index fc557a3..26869cd 100644
--- a/fs/aio.c
+++ b/fs/aio.c
@@ -239,15 +239,23 @@ static void __put_ioctx(struct kioctx *ctx)
 	call_rcu(&ctx->rcu_head, ctx_rcu_free);
 }
 
-#define get_ioctx(kioctx) do {						\
-	BUG_ON(atomic_read(&(kioctx)->users) <= 0);			\
-	atomic_inc(&(kioctx)->users);					\
-} while (0)
-#define put_ioctx(kioctx) do {						\
-	BUG_ON(atomic_read(&(kioctx)->users) <= 0);			\
-	if (unlikely(atomic_dec_and_test(&(kioctx)->users))) 		\
-		__put_ioctx(kioctx);					\
-} while (0)
+static inline void get_ioctx(struct kioctx *kioctx)
+{
+	BUG_ON(atomic_read(&kioctx->users) <= 0);
+	atomic_inc(&kioctx->users);
+}
+
+static inline int try_get_ioctx(struct kioctx *kioctx)
+{
+	return atomic_inc_not_zero(&kioctx->users);
+}
+
+static inline void put_ioctx(struct kioctx *kioctx)
+{
+	BUG_ON(atomic_read(&kioctx->users) <= 0);
+	if (unlikely(atomic_dec_and_test(&kioctx->users)))
+		__put_ioctx(kioctx);
+}
 
 /* ioctx_alloc
  *	Allocates and initializes an ioctx.  Returns an ERR_PTR if it failed.
@@ -601,8 +609,13 @@ static struct kioctx *lookup_ioctx(unsigned long ctx_id)
 	rcu_read_lock();
 
 	hlist_for_each_entry_rcu(ctx, n, &mm->ioctx_list, list) {
-		if (ctx->user_id == ctx_id && !ctx->dead) {
-			get_ioctx(ctx);
+		/*
+		 * RCU protects us against accessing freed memory but
+		 * we have to be careful not to get a reference when the
+		 * reference count already dropped to 0 (ctx->dead test
+		 * is unreliable because of races).
+		 */
+		if (ctx->user_id == ctx_id && !ctx->dead && try_get_ioctx(ctx)){
 			ret = ctx;
 			break;
 		}
@@ -1629,6 +1642,23 @@ static int io_submit_one(struct kioctx *ctx, struct iocb __user *user_iocb,
 		goto out_put_req;
 
 	spin_lock_irq(&ctx->ctx_lock);
+	/*
+	 * We could have raced with io_destroy() and are currently holding a
+	 * reference to ctx which should be destroyed. We cannot submit IO
+	 * since ctx gets freed as soon as io_submit() puts its reference.  The
+	 * check here is reliable: io_destroy() sets ctx->dead before waiting
+	 * for outstanding IO and the barrier between these two is realized by
+	 * unlock of mm->ioctx_lock and lock of ctx->ctx_lock.  Analogously we
+	 * increment ctx->reqs_active before checking for ctx->dead and the
+	 * barrier is realized by unlock and lock of ctx->ctx_lock. Thus if we
+	 * don't see ctx->dead set here, io_destroy() waits for our IO to
+	 * finish.
+	 */
+	if (ctx->dead) {
+		spin_unlock_irq(&ctx->ctx_lock);
+		ret = -EINVAL;
+		goto out_put_req;
+	}
 	aio_run_iocb(req);
 	if (!list_empty(&ctx->run_list)) {
 		/* drain the run list */
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 4fb8a34..8892870 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -873,6 +873,11 @@ int bd_link_disk_holder(struct block_device *bdev, struct gendisk *disk)
 	ret = add_symlink(bdev->bd_part->holder_dir, &disk_to_dev(disk)->kobj);
 	if (ret)
 		goto out_del;
+	/*
+	 * bdev could be deleted beneath us which would implicitly destroy
+	 * the holder directory.  Hold on to it.
+	 */
+	kobject_get(bdev->bd_part->holder_dir);
 
 	list_add(&holder->list, &bdev->bd_holder_disks);
 	goto out_unlock;
@@ -909,6 +914,7 @@ void bd_unlink_disk_holder(struct block_device *bdev, struct gendisk *disk)
 		del_symlink(disk->slave_dir, &part_to_dev(bdev->bd_part)->kobj);
 		del_symlink(bdev->bd_part->holder_dir,
 			    &disk_to_dev(disk)->kobj);
+		kobject_put(bdev->bd_part->holder_dir);
 		list_del_init(&holder->list);
 		kfree(holder);
 	}
@@ -922,14 +928,15 @@ EXPORT_SYMBOL_GPL(bd_unlink_disk_holder);
  * flush_disk - invalidates all buffer-cache entries on a disk
  *
  * @bdev:      struct block device to be flushed
+ * @kill_dirty: flag to guide handling of dirty inodes
  *
  * Invalidates all buffer-cache entries on a disk. It should be called
  * when a disk has been changed -- either by a media change or online
  * resize.
  */
-static void flush_disk(struct block_device *bdev)
+static void flush_disk(struct block_device *bdev, bool kill_dirty)
 {
-	if (__invalidate_device(bdev)) {
+	if (__invalidate_device(bdev, kill_dirty)) {
 		char name[BDEVNAME_SIZE] = "";
 
 		if (bdev->bd_disk)
@@ -966,7 +973,7 @@ void check_disk_size_change(struct gendisk *disk, struct block_device *bdev)
 		       "%s: detected capacity change from %lld to %lld\n",
 		       name, bdev_size, disk_size);
 		i_size_write(bdev->bd_inode, disk_size);
-		flush_disk(bdev);
+		flush_disk(bdev, false);
 	}
 }
 EXPORT_SYMBOL(check_disk_size_change);
@@ -1019,7 +1026,7 @@ int check_disk_change(struct block_device *bdev)
 	if (!(events & DISK_EVENT_MEDIA_CHANGE))
 		return 0;
 
-	flush_disk(bdev);
+	flush_disk(bdev, true);
 	if (bdops->revalidate_disk)
 		bdops->revalidate_disk(bdev->bd_disk);
 	return 1;
@@ -1600,7 +1607,7 @@ fail:
 }
 EXPORT_SYMBOL(lookup_bdev);
 
-int __invalidate_device(struct block_device *bdev)
+int __invalidate_device(struct block_device *bdev, bool kill_dirty)
 {
 	struct super_block *sb = get_super(bdev);
 	int res = 0;
@@ -1613,7 +1620,7 @@ int __invalidate_device(struct block_device *bdev)
 		 * hold).
 		 */
 		shrink_dcache_sb(sb);
-		res = invalidate_inodes(sb);
+		res = invalidate_inodes(sb, kill_dirty);
 		drop_super(sb);
 	}
 	invalidate_bdev(bdev);
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 2c98b3a..6f820fa 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1254,6 +1254,7 @@ struct btrfs_root {
 #define BTRFS_MOUNT_SPACE_CACHE		(1 << 12)
 #define BTRFS_MOUNT_CLEAR_CACHE		(1 << 13)
 #define BTRFS_MOUNT_USER_SUBVOL_RM_ALLOWED (1 << 14)
+#define BTRFS_MOUNT_ENOSPC_DEBUG	 (1 << 15)
 
 #define btrfs_clear_opt(o, opt)		((o) &= ~BTRFS_MOUNT_##opt)
 #define btrfs_set_opt(o, opt)		((o) |= BTRFS_MOUNT_##opt)
@@ -2218,6 +2219,8 @@ int btrfs_error_unpin_extent_range(struct btrfs_root *root,
 				   u64 start, u64 end);
 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
 			       u64 num_bytes);
+int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
+			    struct btrfs_root *root, u64 type);
 
 /* ctree.c */
 int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key,
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index f3c96fc..588ff98 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -5376,7 +5376,7 @@ again:
 			       num_bytes, data, 1);
 		goto again;
 	}
-	if (ret == -ENOSPC) {
+	if (ret == -ENOSPC && btrfs_test_opt(root, ENOSPC_DEBUG)) {
 		struct btrfs_space_info *sinfo;
 
 		sinfo = __find_space_info(root->fs_info, data);
@@ -8065,6 +8065,13 @@ out:
 	return ret;
 }
 
+int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
+			    struct btrfs_root *root, u64 type)
+{
+	u64 alloc_flags = get_alloc_profile(root, type);
+	return do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
+}
+
 /*
  * helper to account the unused space of all the readonly block group in the
  * list. takes mirrors into account.
diff --git a/fs/btrfs/extent_io.c b/fs/btrfs/extent_io.c
index 92ac519..fd3f172 100644
--- a/fs/btrfs/extent_io.c
+++ b/fs/btrfs/extent_io.c
@@ -1433,12 +1433,13 @@ int extent_clear_unlock_delalloc(struct inode *inode,
  */
 u64 count_range_bits(struct extent_io_tree *tree,
 		     u64 *start, u64 search_end, u64 max_bytes,
-		     unsigned long bits)
+		     unsigned long bits, int contig)
 {
 	struct rb_node *node;
 	struct extent_state *state;
 	u64 cur_start = *start;
 	u64 total_bytes = 0;
+	u64 last = 0;
 	int found = 0;
 
 	if (search_end <= cur_start) {
@@ -1463,7 +1464,9 @@ u64 count_range_bits(struct extent_io_tree *tree,
 		state = rb_entry(node, struct extent_state, rb_node);
 		if (state->start > search_end)
 			break;
-		if (state->end >= cur_start && (state->state & bits)) {
+		if (contig && found && state->start > last + 1)
+			break;
+		if (state->end >= cur_start && (state->state & bits) == bits) {
 			total_bytes += min(search_end, state->end) + 1 -
 				       max(cur_start, state->start);
 			if (total_bytes >= max_bytes)
@@ -1472,6 +1475,9 @@ u64 count_range_bits(struct extent_io_tree *tree,
 				*start = state->start;
 				found = 1;
 			}
+			last = state->end;
+		} else if (contig && found) {
+			break;
 		}
 		node = rb_next(node);
 		if (!node)
@@ -2912,6 +2918,46 @@ out:
 	return sector;
 }
 
+/*
+ * helper function for fiemap, which doesn't want to see any holes.
+ * This maps until we find something past 'last'
+ */
+static struct extent_map *get_extent_skip_holes(struct inode *inode,
+						u64 offset,
+						u64 last,
+						get_extent_t *get_extent)
+{
+	u64 sectorsize = BTRFS_I(inode)->root->sectorsize;
+	struct extent_map *em;
+	u64 len;
+
+	if (offset >= last)
+		return NULL;
+
+	while(1) {
+		len = last - offset;
+		if (len == 0)
+			break;
+		len = (len + sectorsize - 1) & ~(sectorsize - 1);
+		em = get_extent(inode, NULL, 0, offset, len, 0);
+		if (!em || IS_ERR(em))
+			return em;
+
+		/* if this isn't a hole return it */
+		if (!test_bit(EXTENT_FLAG_VACANCY, &em->flags) &&
+		    em->block_start != EXTENT_MAP_HOLE) {
+			return em;
+		}
+
+		/* this is a hole, advance to the next extent */
+		offset = extent_map_end(em);
+		free_extent_map(em);
+		if (offset >= last)
+			break;
+	}
+	return NULL;
+}
+
 int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		__u64 start, __u64 len, get_extent_t *get_extent)
 {
@@ -2921,16 +2967,19 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	u32 flags = 0;
 	u32 found_type;
 	u64 last;
+	u64 last_for_get_extent = 0;
 	u64 disko = 0;
+	u64 isize = i_size_read(inode);
 	struct btrfs_key found_key;
 	struct extent_map *em = NULL;
 	struct extent_state *cached_state = NULL;
 	struct btrfs_path *path;
 	struct btrfs_file_extent_item *item;
 	int end = 0;
-	u64 em_start = 0, em_len = 0;
+	u64 em_start = 0;
+	u64 em_len = 0;
+	u64 em_end = 0;
 	unsigned long emflags;
-	int hole = 0;
 
 	if (len == 0)
 		return -EINVAL;
@@ -2940,6 +2989,10 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		return -ENOMEM;
 	path->leave_spinning = 1;
 
+	/*
+	 * lookup the last file extent.  We're not using i_size here
+	 * because there might be preallocation past i_size
+	 */
 	ret = btrfs_lookup_file_extent(NULL, BTRFS_I(inode)->root,
 				       path, inode->i_ino, -1, 0);
 	if (ret < 0) {
@@ -2953,18 +3006,38 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	btrfs_item_key_to_cpu(path->nodes[0], &found_key, path->slots[0]);
 	found_type = btrfs_key_type(&found_key);
 
-	/* No extents, just return */
+	/* No extents, but there might be delalloc bits */
 	if (found_key.objectid != inode->i_ino ||
 	    found_type != BTRFS_EXTENT_DATA_KEY) {
-		btrfs_free_path(path);
-		return 0;
+		/* have to trust i_size as the end */
+		last = (u64)-1;
+		last_for_get_extent = isize;
+	} else {
+		/*
+		 * remember the start of the last extent.  There are a
+		 * bunch of different factors that go into the length of the
+		 * extent, so its much less complex to remember where it started
+		 */
+		last = found_key.offset;
+		last_for_get_extent = last + 1;
 	}
-	last = found_key.offset;
 	btrfs_free_path(path);
 
+	/*
+	 * we might have some extents allocated but more delalloc past those
+	 * extents.  so, we trust isize unless the start of the last extent is
+	 * beyond isize
+	 */
+	if (last < isize) {
+		last = (u64)-1;
+		last_for_get_extent = isize;
+	}
+
 	lock_extent_bits(&BTRFS_I(inode)->io_tree, start, start + len, 0,
 			 &cached_state, GFP_NOFS);
-	em = get_extent(inode, NULL, 0, off, max - off, 0);
+
+	em = get_extent_skip_holes(inode, off, last_for_get_extent,
+				   get_extent);
 	if (!em)
 		goto out;
 	if (IS_ERR(em)) {
@@ -2973,19 +3046,14 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 	}
 
 	while (!end) {
-		hole = 0;
-		off = em->start + em->len;
+		off = extent_map_end(em);
 		if (off >= max)
 			end = 1;
 
-		if (em->block_start == EXTENT_MAP_HOLE) {
-			hole = 1;
-			goto next;
-		}
-
 		em_start = em->start;
 		em_len = em->len;
-
+		em_end = extent_map_end(em);
+		emflags = em->flags;
 		disko = 0;
 		flags = 0;
 
@@ -3004,37 +3072,29 @@ int extent_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		if (test_bit(EXTENT_FLAG_COMPRESSED, &em->flags))
 			flags |= FIEMAP_EXTENT_ENCODED;
 
-next:
-		emflags = em->flags;
 		free_extent_map(em);
 		em = NULL;
-		if (!end) {
-			em = get_extent(inode, NULL, 0, off, max - off, 0);
-			if (!em)
-				goto out;
-			if (IS_ERR(em)) {
-				ret = PTR_ERR(em);
-				goto out;
-			}
-			emflags = em->flags;
-		}
-
-		if (test_bit(EXTENT_FLAG_VACANCY, &emflags)) {
+		if ((em_start >= last) || em_len == (u64)-1 ||
+		   (last == (u64)-1 && isize <= em_end)) {
 			flags |= FIEMAP_EXTENT_LAST;
 			end = 1;
 		}
 
-		if (em_start == last) {
+		/* now scan forward to see if this is really the last extent. */
+		em = get_extent_skip_holes(inode, off, last_for_get_extent,
+					   get_extent);
+		if (IS_ERR(em)) {
+			ret = PTR_ERR(em);
+			goto out;
+		}
+		if (!em) {
 			flags |= FIEMAP_EXTENT_LAST;
 			end = 1;
 		}
-
-		if (!hole) {
-			ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
-						em_len, flags);
-			if (ret)
-				goto out_free;
-		}
+		ret = fiemap_fill_next_extent(fieinfo, em_start, disko,
+					      em_len, flags);
+		if (ret)
+			goto out_free;
 	}
 out_free:
 	free_extent_map(em);
diff --git a/fs/btrfs/extent_io.h b/fs/btrfs/extent_io.h
index 7083cfa..9318dfe 100644
--- a/fs/btrfs/extent_io.h
+++ b/fs/btrfs/extent_io.h
@@ -191,7 +191,7 @@ void extent_io_exit(void);
 
 u64 count_range_bits(struct extent_io_tree *tree,
 		     u64 *start, u64 search_end,
-		     u64 max_bytes, unsigned long bits);
+		     u64 max_bytes, unsigned long bits, int contig);
 
 void free_extent_state(struct extent_state *state);
 int test_range_bit(struct extent_io_tree *tree, u64 start, u64 end,
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index fb9bd78..0efdb65 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1913,7 +1913,7 @@ static int btrfs_clean_io_failures(struct inode *inode, u64 start)
 
 	private = 0;
 	if (count_range_bits(&BTRFS_I(inode)->io_failure_tree, &private,
-			     (u64)-1, 1, EXTENT_DIRTY)) {
+			     (u64)-1, 1, EXTENT_DIRTY, 0)) {
 		ret = get_state_private(&BTRFS_I(inode)->io_failure_tree,
 					start, &private_failure);
 		if (ret == 0) {
@@ -5280,6 +5280,128 @@ out:
 	return em;
 }
 
+struct extent_map *btrfs_get_extent_fiemap(struct inode *inode, struct page *page,
+					   size_t pg_offset, u64 start, u64 len,
+					   int create)
+{
+	struct extent_map *em;
+	struct extent_map *hole_em = NULL;
+	u64 range_start = start;
+	u64 end;
+	u64 found;
+	u64 found_end;
+	int err = 0;
+
+	em = btrfs_get_extent(inode, page, pg_offset, start, len, create);
+	if (IS_ERR(em))
+		return em;
+	if (em) {
+		/*
+		 * if our em maps to a hole, there might
+		 * actually be delalloc bytes behind it
+		 */
+		if (em->block_start != EXTENT_MAP_HOLE)
+			return em;
+		else
+			hole_em = em;
+	}
+
+	/* check to see if we've wrapped (len == -1 or similar) */
+	end = start + len;
+	if (end < start)
+		end = (u64)-1;
+	else
+		end -= 1;
+
+	em = NULL;
+
+	/* ok, we didn't find anything, lets look for delalloc */
+	found = count_range_bits(&BTRFS_I(inode)->io_tree, &range_start,
+				 end, len, EXTENT_DELALLOC, 1);
+	found_end = range_start + found;
+	if (found_end < range_start)
+		found_end = (u64)-1;
+
+	/*
+	 * we didn't find anything useful, return
+	 * the original results from get_extent()
+	 */
+	if (range_start > end || found_end <= start) {
+		em = hole_em;
+		hole_em = NULL;
+		goto out;
+	}
+
+	/* adjust the range_start to make sure it doesn't
+	 * go backwards from the start they passed in
+	 */
+	range_start = max(start,range_start);
+	found = found_end - range_start;
+
+	if (found > 0) {
+		u64 hole_start = start;
+		u64 hole_len = len;
+
+		em = alloc_extent_map(GFP_NOFS);
+		if (!em) {
+			err = -ENOMEM;
+			goto out;
+		}
+		/*
+		 * when btrfs_get_extent can't find anything it
+		 * returns one huge hole
+		 *
+		 * make sure what it found really fits our range, and
+		 * adjust to make sure it is based on the start from
+		 * the caller
+		 */
+		if (hole_em) {
+			u64 calc_end = extent_map_end(hole_em);
+
+			if (calc_end <= start || (hole_em->start > end)) {
+				free_extent_map(hole_em);
+				hole_em = NULL;
+			} else {
+				hole_start = max(hole_em->start, start);
+				hole_len = calc_end - hole_start;
+			}
+		}
+		em->bdev = NULL;
+		if (hole_em && range_start > hole_start) {
+			/* our hole starts before our delalloc, so we
+			 * have to return just the parts of the hole
+			 * that go until  the delalloc starts
+			 */
+			em->len = min(hole_len,
+				      range_start - hole_start);
+			em->start = hole_start;
+			em->orig_start = hole_start;
+			/*
+			 * don't adjust block start at all,
+			 * it is fixed at EXTENT_MAP_HOLE
+			 */
+			em->block_start = hole_em->block_start;
+			em->block_len = hole_len;
+		} else {
+			em->start = range_start;
+			em->len = found;
+			em->orig_start = range_start;
+			em->block_start = EXTENT_MAP_DELALLOC;
+			em->block_len = found;
+		}
+	} else if (hole_em) {
+		return hole_em;
+	}
+out:
+
+	free_extent_map(hole_em);
+	if (err) {
+		free_extent_map(em);
+		return ERR_PTR(err);
+	}
+	return em;
+}
+
 static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
 						  u64 start, u64 len)
 {
@@ -6102,7 +6224,7 @@ out:
 static int btrfs_fiemap(struct inode *inode, struct fiemap_extent_info *fieinfo,
 		__u64 start, __u64 len)
 {
-	return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent);
+	return extent_fiemap(inode, fieinfo, start, len, btrfs_get_extent_fiemap);
 }
 
 int btrfs_readpage(struct file *file, struct page *page)
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index be2d4f6..5fdb2ab 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -1071,12 +1071,15 @@ static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
 	if (copy_from_user(&flags, arg, sizeof(flags)))
 		return -EFAULT;
 
-	if (flags & ~BTRFS_SUBVOL_CREATE_ASYNC)
+	if (flags & BTRFS_SUBVOL_CREATE_ASYNC)
 		return -EINVAL;
 
 	if (flags & ~BTRFS_SUBVOL_RDONLY)
 		return -EOPNOTSUPP;
 
+	if (!is_owner_or_cap(inode))
+		return -EACCES;
+
 	down_write(&root->fs_info->subvol_sem);
 
 	/* nothing to do */
@@ -1097,7 +1100,7 @@ static noinline int btrfs_ioctl_subvol_setflags(struct file *file,
 		goto out_reset;
 	}
 
-	ret = btrfs_update_root(trans, root,
+	ret = btrfs_update_root(trans, root->fs_info->tree_root,
 				&root->root_key, &root->root_item);
 
 	btrfs_commit_transaction(trans, root);
diff --git a/fs/btrfs/lzo.c b/fs/btrfs/lzo.c
index cc9b450..a178f5e 100644
--- a/fs/btrfs/lzo.c
+++ b/fs/btrfs/lzo.c
@@ -280,6 +280,7 @@ static int lzo_decompress_biovec(struct list_head *ws,
 	unsigned long tot_out;
 	unsigned long tot_len;
 	char *buf;
+	bool may_late_unmap, need_unmap;
 
 	data_in = kmap(pages_in[0]);
 	tot_len = read_compress_length(data_in);
@@ -300,11 +301,13 @@ static int lzo_decompress_biovec(struct list_head *ws,
 
 		tot_in += in_len;
 		working_bytes = in_len;
+		may_late_unmap = need_unmap = false;
 
 		/* fast path: avoid using the working buffer */
 		if (in_page_bytes_left >= in_len) {
 			buf = data_in + in_offset;
 			bytes = in_len;
+			may_late_unmap = true;
 			goto cont;
 		}
 
@@ -329,14 +332,17 @@ cont:
 				if (working_bytes == 0 && tot_in >= tot_len)
 					break;
 
-				kunmap(pages_in[page_in_index]);
-				page_in_index++;
-				if (page_in_index >= total_pages_in) {
+				if (page_in_index + 1 >= total_pages_in) {
 					ret = -1;
-					data_in = NULL;
 					goto done;
 				}
-				data_in = kmap(pages_in[page_in_index]);
+
+				if (may_late_unmap)
+					need_unmap = true;
+				else
+					kunmap(pages_in[page_in_index]);
+
+				data_in = kmap(pages_in[++page_in_index]);
 
 				in_page_bytes_left = PAGE_CACHE_SIZE;
 				in_offset = 0;
@@ -346,6 +352,8 @@ cont:
 		out_len = lzo1x_worst_compress(PAGE_CACHE_SIZE);
 		ret = lzo1x_decompress_safe(buf, in_len, workspace->buf,
 					    &out_len);
+		if (need_unmap)
+			kunmap(pages_in[page_in_index - 1]);
 		if (ret != LZO_E_OK) {
 			printk(KERN_WARNING "btrfs decompress failed\n");
 			ret = -1;
@@ -363,8 +371,7 @@ cont:
 			break;
 	}
 done:
-	if (data_in)
-		kunmap(pages_in[page_in_index]);
+	kunmap(pages_in[page_in_index]);
 	return ret;
 }
 
diff --git a/fs/btrfs/relocation.c b/fs/btrfs/relocation.c
index 0825e4e..31ade58 100644
--- a/fs/btrfs/relocation.c
+++ b/fs/btrfs/relocation.c
@@ -3654,6 +3654,7 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 	u32 item_size;
 	int ret;
 	int err = 0;
+	int progress = 0;
 
 	path = btrfs_alloc_path();
 	if (!path)
@@ -3666,9 +3667,10 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 	}
 
 	while (1) {
+		progress++;
 		trans = btrfs_start_transaction(rc->extent_root, 0);
 		BUG_ON(IS_ERR(trans));
-
+restart:
 		if (update_backref_cache(trans, &rc->backref_cache)) {
 			btrfs_end_transaction(trans, rc->extent_root);
 			continue;
@@ -3781,6 +3783,15 @@ static noinline_for_stack int relocate_block_group(struct reloc_control *rc)
 			}
 		}
 	}
+	if (trans && progress && err == -ENOSPC) {
+		ret = btrfs_force_chunk_alloc(trans, rc->extent_root,
+					      rc->block_group->flags);
+		if (ret == 0) {
+			err = 0;
+			progress = 0;
+			goto restart;
+		}
+	}
 
 	btrfs_release_path(rc->extent_root, path);
 	clear_extent_bits(&rc->processed_blocks, 0, (u64)-1, EXTENT_DIRTY,
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c
index a004008..d39a989 100644
--- a/fs/btrfs/super.c
+++ b/fs/btrfs/super.c
@@ -155,7 +155,8 @@ enum {
 	Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress,
 	Opt_compress_type, Opt_compress_force, Opt_compress_force_type,
 	Opt_notreelog, Opt_ratio, Opt_flushoncommit, Opt_discard,
-	Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed, Opt_err,
+	Opt_space_cache, Opt_clear_cache, Opt_user_subvol_rm_allowed,
+	Opt_enospc_debug, Opt_err,
 };
 
 static match_table_t tokens = {
@@ -184,6 +185,7 @@ static match_table_t tokens = {
 	{Opt_space_cache, "space_cache"},
 	{Opt_clear_cache, "clear_cache"},
 	{Opt_user_subvol_rm_allowed, "user_subvol_rm_allowed"},
+	{Opt_enospc_debug, "enospc_debug"},
 	{Opt_err, NULL},
 };
 
@@ -358,6 +360,9 @@ int btrfs_parse_options(struct btrfs_root *root, char *options)
 		case Opt_user_subvol_rm_allowed:
 			btrfs_set_opt(info->mount_opt, USER_SUBVOL_RM_ALLOWED);
 			break;
+		case Opt_enospc_debug:
+			btrfs_set_opt(info->mount_opt, ENOSPC_DEBUG);
+			break;
 		case Opt_err:
 			printk(KERN_INFO "btrfs: unrecognized mount option "
 			       "'%s'\n", p);
diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index af7dbca..dd13eb8 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -1338,11 +1338,11 @@ int btrfs_rm_device(struct btrfs_root *root, char *device_path)
 
 	ret = btrfs_shrink_device(device, 0);
 	if (ret)
-		goto error_brelse;
+		goto error_undo;
 
 	ret = btrfs_rm_dev_item(root->fs_info->chunk_root, device);
 	if (ret)
-		goto error_brelse;
+		goto error_undo;
 
 	device->in_fs_metadata = 0;
 
@@ -1416,6 +1416,13 @@ out:
 	mutex_unlock(&root->fs_info->volume_mutex);
 	mutex_unlock(&uuid_mutex);
 	return ret;
+error_undo:
+	if (device->writeable) {
+		list_add(&device->dev_alloc_list,
+			 &root->fs_info->fs_devices->alloc_list);
+		root->fs_info->fs_devices->rw_devices++;
+	}
+	goto error_brelse;
 }
 
 /*
@@ -1633,7 +1640,7 @@ int btrfs_init_new_device(struct btrfs_root *root, char *device_path)
 	device->dev_root = root->fs_info->dev_root;
 	device->bdev = bdev;
 	device->in_fs_metadata = 1;
-	device->mode = 0;
+	device->mode = FMODE_EXCL;
 	set_blocksize(device->bdev, 4096);
 
 	if (seeding_dev) {
diff --git a/fs/eventpoll.c b/fs/eventpoll.c
index 267d0ad..4a09af9 100644
--- a/fs/eventpoll.c
+++ b/fs/eventpoll.c
@@ -63,6 +63,13 @@
  * cleanup path and it is also acquired by eventpoll_release_file()
  * if a file has been pushed inside an epoll set and it is then
  * close()d without a previous call toepoll_ctl(EPOLL_CTL_DEL).
+ * It is also acquired when inserting an epoll fd onto another epoll
+ * fd. We do this so that we walk the epoll tree and ensure that this
+ * insertion does not create a cycle of epoll file descriptors, which
+ * could lead to deadlock. We need a global mutex to prevent two
+ * simultaneous inserts (A into B and B into A) from racing and
+ * constructing a cycle without either insert observing that it is
+ * going to.
  * It is possible to drop the "ep->mtx" and to use the global
  * mutex "epmutex" (together with "ep->lock") to have it working,
  * but having "ep->mtx" will make the interface more scalable.
@@ -224,6 +231,9 @@ static long max_user_watches __read_mostly;
  */
 static DEFINE_MUTEX(epmutex);
 
+/* Used to check for epoll file descriptor inclusion loops */
+static struct nested_calls poll_loop_ncalls;
+
 /* Used for safe wake up implementation */
 static struct nested_calls poll_safewake_ncalls;
 
@@ -1198,6 +1208,62 @@ retry:
 	return res;
 }
 
+/**
+ * ep_loop_check_proc - Callback function to be passed to the @ep_call_nested()
+ *                      API, to verify that adding an epoll file inside another
+ *                      epoll structure, does not violate the constraints, in
+ *                      terms of closed loops, or too deep chains (which can
+ *                      result in excessive stack usage).
+ *
+ * @priv: Pointer to the epoll file to be currently checked.
+ * @cookie: Original cookie for this call. This is the top-of-the-chain epoll
+ *          data structure pointer.
+ * @call_nests: Current dept of the @ep_call_nested() call stack.
+ *
+ * Returns: Returns zero if adding the epoll @file inside current epoll
+ *          structure @ep does not violate the constraints, or -1 otherwise.
+ */
+static int ep_loop_check_proc(void *priv, void *cookie, int call_nests)
+{
+	int error = 0;
+	struct file *file = priv;
+	struct eventpoll *ep = file->private_data;
+	struct rb_node *rbp;
+	struct epitem *epi;
+
+	mutex_lock(&ep->mtx);
+	for (rbp = rb_first(&ep->rbr); rbp; rbp = rb_next(rbp)) {
+		epi = rb_entry(rbp, struct epitem, rbn);
+		if (unlikely(is_file_epoll(epi->ffd.file))) {
+			error = ep_call_nested(&poll_loop_ncalls, EP_MAX_NESTS,
+					       ep_loop_check_proc, epi->ffd.file,
+					       epi->ffd.file->private_data, current);
+			if (error != 0)
+				break;
+		}
+	}
+	mutex_unlock(&ep->mtx);
+
+	return error;
+}
+
+/**
+ * ep_loop_check - Performs a check to verify that adding an epoll file (@file)
+ *                 another epoll file (represented by @ep) does not create
+ *                 closed loops or too deep chains.
+ *
+ * @ep: Pointer to the epoll private data structure.
+ * @file: Pointer to the epoll file to be checked.
+ *
+ * Returns: Returns zero if adding the epoll @file inside current epoll
+ *          structure @ep does not violate the constraints, or -1 otherwise.
+ */
+static int ep_loop_check(struct eventpoll *ep, struct file *file)
+{
+	return ep_call_nested(&poll_loop_ncalls, EP_MAX_NESTS,
+			      ep_loop_check_proc, file, ep, current);
+}
+
 /*
  * Open an eventpoll file descriptor.
  */
@@ -1246,6 +1312,7 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd,
 		struct epoll_event __user *, event)
 {
 	int error;
+	int did_lock_epmutex = 0;
 	struct file *file, *tfile;
 	struct eventpoll *ep;
 	struct epitem *epi;
@@ -1287,6 +1354,25 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd,
 	 */
 	ep = file->private_data;
 
+	/*
+	 * When we insert an epoll file descriptor, inside another epoll file
+	 * descriptor, there is the change of creating closed loops, which are
+	 * better be handled here, than in more critical paths.
+	 *
+	 * We hold epmutex across the loop check and the insert in this case, in
+	 * order to prevent two separate inserts from racing and each doing the
+	 * insert "at the same time" such that ep_loop_check passes on both
+	 * before either one does the insert, thereby creating a cycle.
+	 */
+	if (unlikely(is_file_epoll(tfile) && op == EPOLL_CTL_ADD)) {
+		mutex_lock(&epmutex);
+		did_lock_epmutex = 1;
+		error = -ELOOP;
+		if (ep_loop_check(ep, tfile) != 0)
+			goto error_tgt_fput;
+	}
+
+
 	mutex_lock(&ep->mtx);
 
 	/*
@@ -1322,6 +1408,9 @@ SYSCALL_DEFINE4(epoll_ctl, int, epfd, int, op, int, fd,
 	mutex_unlock(&ep->mtx);
 
 error_tgt_fput:
+	if (unlikely(did_lock_epmutex))
+		mutex_unlock(&epmutex);
+
 	fput(tfile);
 error_fput:
 	fput(file);
@@ -1441,6 +1530,12 @@ static int __init eventpoll_init(void)
 		EP_ITEM_COST;
 	BUG_ON(max_user_watches < 0);
 
+	/*
+	 * Initialize the structure used to perform epoll file descriptor
+	 * inclusion loops checks.
+	 */
+	ep_nested_calls_init(&poll_loop_ncalls);
+
 	/* Initialize the structure used to perform safe poll wait head wake ups */
 	ep_nested_calls_init(&poll_safewake_ncalls);
 
diff --git a/fs/fuse/dir.c b/fs/fuse/dir.c
index bfed844..83543b5 100644
--- a/fs/fuse/dir.c
+++ b/fs/fuse/dir.c
@@ -1283,8 +1283,11 @@ static int fuse_do_setattr(struct dentry *entry, struct iattr *attr,
 	if (err)
 		return err;
 
-	if ((attr->ia_valid & ATTR_OPEN) && fc->atomic_o_trunc)
-		return 0;
+	if (attr->ia_valid & ATTR_OPEN) {
+		if (fc->atomic_o_trunc)
+			return 0;
+		file = NULL;
+	}
 
 	if (attr->ia_valid & ATTR_SIZE)
 		is_truncate = true;
diff --git a/fs/fuse/file.c b/fs/fuse/file.c
index 95da1bc..9e0832d 100644
--- a/fs/fuse/file.c
+++ b/fs/fuse/file.c
@@ -86,18 +86,52 @@ struct fuse_file *fuse_file_get(struct fuse_file *ff)
 	return ff;
 }
 
+static void fuse_release_async(struct work_struct *work)
+{
+	struct fuse_req *req;
+	struct fuse_conn *fc;
+	struct path path;
+
+	req = container_of(work, struct fuse_req, misc.release.work);
+	path = req->misc.release.path;
+	fc = get_fuse_conn(path.dentry->d_inode);
+
+	fuse_put_request(fc, req);
+	path_put(&path);
+}
+
 static void fuse_release_end(struct fuse_conn *fc, struct fuse_req *req)
 {
-	path_put(&req->misc.release.path);
+	if (fc->destroy_req) {
+		/*
+		 * If this is a fuseblk mount, then it's possible that
+		 * releasing the path will result in releasing the
+		 * super block and sending the DESTROY request.  If
+		 * the server is single threaded, this would hang.
+		 * For this reason do the path_put() in a separate
+		 * thread.
+		 */
+		atomic_inc(&req->count);
+		INIT_WORK(&req->misc.release.work, fuse_release_async);
+		schedule_work(&req->misc.release.work);
+	} else {
+		path_put(&req->misc.release.path);
+	}
 }
 
-static void fuse_file_put(struct fuse_file *ff)
+static void fuse_file_put(struct fuse_file *ff, bool sync)
 {
 	if (atomic_dec_and_test(&ff->count)) {
 		struct fuse_req *req = ff->reserved_req;
 
-		req->end = fuse_release_end;
-		fuse_request_send_background(ff->fc, req);
+		if (sync) {
+			fuse_request_send(ff->fc, req);
+			path_put(&req->misc.release.path);
+			fuse_put_request(ff->fc, req);
+		} else {
+			req->end = fuse_release_end;
+			fuse_request_send_background(ff->fc, req);
+		}
 		kfree(ff);
 	}
 }
@@ -219,8 +253,12 @@ void fuse_release_common(struct file *file, int opcode)
 	 * Normally this will send the RELEASE request, however if
 	 * some asynchronous READ or WRITE requests are outstanding,
 	 * the sending will be delayed.
+	 *
+	 * Make the release synchronous if this is a fuseblk mount,
+	 * synchronous RELEASE is allowed (and desirable) in this case
+	 * because the server can be trusted not to screw up.
 	 */
-	fuse_file_put(ff);
+	fuse_file_put(ff, ff->fc->destroy_req != NULL);
 }
 
 static int fuse_open(struct inode *inode, struct file *file)
@@ -558,7 +596,7 @@ static void fuse_readpages_end(struct fuse_conn *fc, struct fuse_req *req)
 		page_cache_release(page);
 	}
 	if (req->ff)
-		fuse_file_put(req->ff);
+		fuse_file_put(req->ff, false);
 }
 
 static void fuse_send_readpages(struct fuse_req *req, struct file *file)
@@ -1137,7 +1175,7 @@ static ssize_t fuse_direct_write(struct file *file, const char __user *buf,
 static void fuse_writepage_free(struct fuse_conn *fc, struct fuse_req *req)
 {
 	__free_page(req->pages[0]);
-	fuse_file_put(req->ff);
+	fuse_file_put(req->ff, false);
 }
 
 static void fuse_writepage_finish(struct fuse_conn *fc, struct fuse_req *req)
diff --git a/fs/fuse/fuse_i.h b/fs/fuse/fuse_i.h
index ae5744a..d428694 100644
--- a/fs/fuse/fuse_i.h
+++ b/fs/fuse/fuse_i.h
@@ -21,6 +21,7 @@
 #include <linux/rwsem.h>
 #include <linux/rbtree.h>
 #include <linux/poll.h>
+#include <linux/workqueue.h>
 
 /** Max number of pages that can be used in a single read request */
 #define FUSE_MAX_PAGES_PER_REQ 32
@@ -262,7 +263,10 @@ struct fuse_req {
 	/** Data for asynchronous requests */
 	union {
 		struct {
-			struct fuse_release_in in;
+			union {
+				struct fuse_release_in in;
+				struct work_struct work;
+			};
 			struct path path;
 		} release;
 		struct fuse_init_in init_in;
diff --git a/fs/inode.c b/fs/inode.c
index 9c2b795..0647d80 100644
--- a/fs/inode.c
+++ b/fs/inode.c
@@ -548,11 +548,14 @@ void evict_inodes(struct super_block *sb)
 /**
  * invalidate_inodes	- attempt to free all inodes on a superblock
  * @sb:		superblock to operate on
+ * @kill_dirty: flag to guide handling of dirty inodes
  *
  * Attempts to free all inodes for a given superblock.  If there were any
  * busy inodes return a non-zero value, else zero.
+ * If @kill_dirty is set, discard dirty inodes too, otherwise treat
+ * them as busy.
  */
-int invalidate_inodes(struct super_block *sb)
+int invalidate_inodes(struct super_block *sb, bool kill_dirty)
 {
 	int busy = 0;
 	struct inode *inode, *next;
@@ -564,6 +567,10 @@ int invalidate_inodes(struct super_block *sb)
 	list_for_each_entry_safe(inode, next, &sb->s_inodes, i_sb_list) {
 		if (inode->i_state & (I_NEW | I_FREEING | I_WILL_FREE))
 			continue;
+		if (inode->i_state & I_DIRTY && !kill_dirty) {
+			busy = 1;
+			continue;
+		}
 		if (atomic_read(&inode->i_count)) {
 			busy = 1;
 			continue;
diff --git a/fs/internal.h b/fs/internal.h
index 0663568..9b976b5 100644
--- a/fs/internal.h
+++ b/fs/internal.h
@@ -112,4 +112,4 @@ extern void release_open_intent(struct nameidata *);
  */
 extern int get_nr_dirty_inodes(void);
 extern void evict_inodes(struct super_block *);
-extern int invalidate_inodes(struct super_block *);
+extern int invalidate_inodes(struct super_block *, bool);
diff --git a/fs/namespace.c b/fs/namespace.c
index 7b0b953..d1edf26 100644
--- a/fs/namespace.c
+++ b/fs/namespace.c
@@ -1244,7 +1244,7 @@ static int do_umount(struct vfsmount *mnt, int flags)
 		 */
 		br_write_lock(vfsmount_lock);
 		if (mnt_get_count(mnt) != 2) {
-			br_write_lock(vfsmount_lock);
+			br_write_unlock(vfsmount_lock);
 			return -EBUSY;
 		}
 		br_write_unlock(vfsmount_lock);
diff --git a/fs/ocfs2/journal.h b/fs/ocfs2/journal.h
index 43e56b9..6180da1 100644
--- a/fs/ocfs2/journal.h
+++ b/fs/ocfs2/journal.h
@@ -405,9 +405,9 @@ static inline int ocfs2_remove_extent_credits(struct super_block *sb)
 	       ocfs2_quota_trans_credits(sb);
 }
 
-/* data block for new dir/symlink, 2 for bitmap updates (bitmap fe +
- * bitmap block for the new bit) dx_root update for free list */
-#define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + 2 + 1)
+/* data block for new dir/symlink, allocation of directory block, dx_root
+ * update for free list */
+#define OCFS2_DIR_LINK_ADDITIONAL_CREDITS (1 + OCFS2_SUBALLOC_ALLOC + 1)
 
 static inline int ocfs2_add_dir_index_credits(struct super_block *sb)
 {
diff --git a/fs/ocfs2/refcounttree.c b/fs/ocfs2/refcounttree.c
index b5f9160..19ebc5a 100644
--- a/fs/ocfs2/refcounttree.c
+++ b/fs/ocfs2/refcounttree.c
@@ -3228,7 +3228,7 @@ static int ocfs2_make_clusters_writable(struct super_block *sb,
 					u32 num_clusters, unsigned int e_flags)
 {
 	int ret, delete, index, credits =  0;
-	u32 new_bit, new_len;
+	u32 new_bit, new_len, orig_num_clusters;
 	unsigned int set_len;
 	struct ocfs2_super *osb = OCFS2_SB(sb);
 	handle_t *handle;
@@ -3261,6 +3261,8 @@ static int ocfs2_make_clusters_writable(struct super_block *sb,
 		goto out;
 	}
 
+	orig_num_clusters = num_clusters;
+
 	while (num_clusters) {
 		ret = ocfs2_get_refcount_rec(ref_ci, context->ref_root_bh,
 					     p_cluster, num_clusters,
@@ -3348,7 +3350,8 @@ static int ocfs2_make_clusters_writable(struct super_block *sb,
 	 * in write-back mode.
 	 */
 	if (context->get_clusters == ocfs2_di_get_clusters) {
-		ret = ocfs2_cow_sync_writeback(sb, context, cpos, num_clusters);
+		ret = ocfs2_cow_sync_writeback(sb, context, cpos,
+					       orig_num_clusters);
 		if (ret)
 			mlog_errno(ret);
 	}
diff --git a/fs/ocfs2/super.c b/fs/ocfs2/super.c
index 38f986d..36c423f 100644
--- a/fs/ocfs2/super.c
+++ b/fs/ocfs2/super.c
@@ -1316,7 +1316,7 @@ static int ocfs2_parse_options(struct super_block *sb,
 			       struct mount_options *mopt,
 			       int is_remount)
 {
-	int status;
+	int status, user_stack = 0;
 	char *p;
 	u32 tmp;
 
@@ -1459,6 +1459,15 @@ static int ocfs2_parse_options(struct super_block *sb,
 			memcpy(mopt->cluster_stack, args[0].from,
 			       OCFS2_STACK_LABEL_LEN);
 			mopt->cluster_stack[OCFS2_STACK_LABEL_LEN] = '\0';
+			/*
+			 * Open code the memcmp here as we don't have
+			 * an osb to pass to
+			 * ocfs2_userspace_stack().
+			 */
+			if (memcmp(mopt->cluster_stack,
+				   OCFS2_CLASSIC_CLUSTER_STACK,
+				   OCFS2_STACK_LABEL_LEN))
+				user_stack = 1;
 			break;
 		case Opt_inode64:
 			mopt->mount_opt |= OCFS2_MOUNT_INODE64;
@@ -1514,13 +1523,16 @@ static int ocfs2_parse_options(struct super_block *sb,
 		}
 	}
 
-	/* Ensure only one heartbeat mode */
-	tmp = mopt->mount_opt & (OCFS2_MOUNT_HB_LOCAL | OCFS2_MOUNT_HB_GLOBAL |
-				 OCFS2_MOUNT_HB_NONE);
-	if (hweight32(tmp) != 1) {
-		mlog(ML_ERROR, "Invalid heartbeat mount options\n");
-		status = 0;
-		goto bail;
+	if (user_stack == 0) {
+		/* Ensure only one heartbeat mode */
+		tmp = mopt->mount_opt & (OCFS2_MOUNT_HB_LOCAL |
+					 OCFS2_MOUNT_HB_GLOBAL |
+					 OCFS2_MOUNT_HB_NONE);
+		if (hweight32(tmp) != 1) {
+			mlog(ML_ERROR, "Invalid heartbeat mount options\n");
+			status = 0;
+			goto bail;
+		}
 	}
 
 	status = 1;
diff --git a/fs/partitions/ldm.c b/fs/partitions/ldm.c
index 789c625..b10e354 100644
--- a/fs/partitions/ldm.c
+++ b/fs/partitions/ldm.c
@@ -251,6 +251,11 @@ static bool ldm_parse_vmdb (const u8 *data, struct vmdb *vm)
 	}
 
 	vm->vblk_size     = get_unaligned_be32(data + 0x08);
+	if (vm->vblk_size == 0) {
+		ldm_error ("Illegal VBLK size");
+		return false;
+	}
+
 	vm->vblk_offset   = get_unaligned_be32(data + 0x0C);
 	vm->last_vblk_seq = get_unaligned_be32(data + 0x04);