1 files changed, 150 insertions, 14 deletions

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index 160b55b3e132..0efdb65953c5 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -416,7 +416,7 @@ again:
 	}
 	if (start == 0) {
 		trans = btrfs_join_transaction(root, 1);
-		BUG_ON(!trans);
+		BUG_ON(IS_ERR(trans));
 		btrfs_set_trans_block_group(trans, inode);
 		trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -612,6 +612,7 @@ retry:
 			    GFP_NOFS);
 
 		trans = btrfs_join_transaction(root, 1);
+		BUG_ON(IS_ERR(trans));
 		ret = btrfs_reserve_extent(trans, root,
 					   async_extent->compressed_size,
 					   async_extent->compressed_size,
@@ -643,6 +644,7 @@ retry:
 					async_extent->ram_size - 1, 0);
 
 		em = alloc_extent_map(GFP_NOFS);
+		BUG_ON(!em);
 		em->start = async_extent->start;
 		em->len = async_extent->ram_size;
 		em->orig_start = em->start;
@@ -771,7 +773,7 @@ static noinline int cow_file_range(struct inode *inode,
 
 	BUG_ON(root == root->fs_info->tree_root);
 	trans = btrfs_join_transaction(root, 1);
-	BUG_ON(!trans);
+	BUG_ON(IS_ERR(trans));
 	btrfs_set_trans_block_group(trans, inode);
 	trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -819,6 +821,7 @@ static noinline int cow_file_range(struct inode *inode,
 		BUG_ON(ret);
 
 		em = alloc_extent_map(GFP_NOFS);
+		BUG_ON(!em);
 		em->start = start;
 		em->orig_start = em->start;
 		ram_size = ins.offset;
@@ -1049,7 +1052,7 @@ static noinline int run_delalloc_nocow(struct inode *inode,
 	} else {
 		trans = btrfs_join_transaction(root, 1);
 	}
-	BUG_ON(!trans);
+	BUG_ON(IS_ERR(trans));
 
 	cow_start = (u64)-1;
 	cur_offset = start;
@@ -1168,6 +1171,7 @@ out_check:
 			struct extent_map_tree *em_tree;
 			em_tree = &BTRFS_I(inode)->extent_tree;
 			em = alloc_extent_map(GFP_NOFS);
+			BUG_ON(!em);
 			em->start = cur_offset;
 			em->orig_start = em->start;
 			em->len = num_bytes;
@@ -1557,6 +1561,7 @@ out:
 out_page:
 	unlock_page(page);
 	page_cache_release(page);
+	kfree(fixup);
 }
 
 /*
@@ -1703,7 +1708,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
 				trans = btrfs_join_transaction_nolock(root, 1);
 			else
 				trans = btrfs_join_transaction(root, 1);
-			BUG_ON(!trans);
+			BUG_ON(IS_ERR(trans));
 			btrfs_set_trans_block_group(trans, inode);
 			trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 			ret = btrfs_update_inode(trans, root, inode);
@@ -1720,6 +1725,7 @@ static int btrfs_finish_ordered_io(struct inode *inode, u64 start, u64 end)
 		trans = btrfs_join_transaction_nolock(root, 1);
 	else
 		trans = btrfs_join_transaction(root, 1);
+	BUG_ON(IS_ERR(trans));
 	btrfs_set_trans_block_group(trans, inode);
 	trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -1907,7 +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) {
@@ -2354,6 +2360,7 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
 		 */
 		if (is_bad_inode(inode)) {
 			trans = btrfs_start_transaction(root, 0);
+			BUG_ON(IS_ERR(trans));
 			btrfs_orphan_del(trans, inode);
 			btrfs_end_transaction(trans, root);
 			iput(inode);
@@ -2381,6 +2388,7 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
 
 	if (root->orphan_block_rsv || root->orphan_item_inserted) {
 		trans = btrfs_join_transaction(root, 1);
+		BUG_ON(IS_ERR(trans));
 		btrfs_end_transaction(trans, root);
 	}
 
@@ -2641,7 +2649,7 @@ int btrfs_unlink_inode(struct btrfs_trans_handle *trans,
 	path = btrfs_alloc_path();
 	if (!path) {
 		ret = -ENOMEM;
-		goto err;
+		goto out;
 	}
 
 	path->leave_spinning = 1;
@@ -2714,9 +2722,10 @@ static int check_path_shared(struct btrfs_root *root,
 	struct extent_buffer *eb;
 	int level;
 	u64 refs = 1;
-	int uninitialized_var(ret);
 
 	for (level = 0; level < BTRFS_MAX_LEVEL; level++) {
+		int ret;
+
 		if (!path->nodes[level])
 			break;
 		eb = path->nodes[level];
@@ -2727,7 +2736,7 @@ static int check_path_shared(struct btrfs_root *root,
 		if (refs > 1)
 			return 1;
 	}
-	return ret; /* XXX callers? */
+	return 0;
 }
 
 /*
@@ -4134,7 +4143,7 @@ struct inode *btrfs_lookup_dentry(struct inode *dir, struct dentry *dentry)
 	}
 	srcu_read_unlock(&root->fs_info->subvol_srcu, index);
 
-	if (root != sub_root) {
+	if (!IS_ERR(inode) && root != sub_root) {
 		down_read(&root->fs_info->cleanup_work_sem);
 		if (!(inode->i_sb->s_flags & MS_RDONLY))
 			btrfs_orphan_cleanup(sub_root);
@@ -4347,6 +4356,8 @@ int btrfs_write_inode(struct inode *inode, struct writeback_control *wbc)
 			trans = btrfs_join_transaction_nolock(root, 1);
 		else
 			trans = btrfs_join_transaction(root, 1);
+		if (IS_ERR(trans))
+			return PTR_ERR(trans);
 		btrfs_set_trans_block_group(trans, inode);
 		if (nolock)
 			ret = btrfs_end_transaction_nolock(trans, root);
@@ -4372,6 +4383,7 @@ void btrfs_dirty_inode(struct inode *inode)
 		return;
 
 	trans = btrfs_join_transaction(root, 1);
+	BUG_ON(IS_ERR(trans));
 	btrfs_set_trans_block_group(trans, inode);
 
 	ret = btrfs_update_inode(trans, root, inode);
@@ -5176,6 +5188,8 @@ again:
 				em = NULL;
 				btrfs_release_path(root, path);
 				trans = btrfs_join_transaction(root, 1);
+				if (IS_ERR(trans))
+					return ERR_CAST(trans);
 				goto again;
 			}
 			map = kmap(page);
@@ -5266,6 +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)
 {
@@ -5280,8 +5416,8 @@ static struct extent_map *btrfs_new_extent_direct(struct inode *inode,
 	btrfs_drop_extent_cache(inode, start, start + len - 1, 0);
 
 	trans = btrfs_join_transaction(root, 0);
-	if (!trans)
-		return ERR_PTR(-ENOMEM);
+	if (IS_ERR(trans))
+		return ERR_CAST(trans);
 
 	trans->block_rsv = &root->fs_info->delalloc_block_rsv;
 
@@ -5505,7 +5641,7 @@ static int btrfs_get_blocks_direct(struct inode *inode, sector_t iblock,
 		 * while we look for nocow cross refs
 		 */
 		trans = btrfs_join_transaction(root, 0);
-		if (!trans)
+		if (IS_ERR(trans))
 			goto must_cow;
 
 		if (can_nocow_odirect(trans, inode, start, len) == 1) {
@@ -5640,7 +5776,7 @@ again:
 	BUG_ON(!ordered);
 
 	trans = btrfs_join_transaction(root, 1);
-	if (!trans) {
+	if (IS_ERR(trans)) {
 		err = -ENOMEM;
 		goto out;
 	}
@@ -6088,7 +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)