Btrfs: check return value of btrfs_alloc_path()

Adding the check on the return value of btrfs_alloc_path() to several places.
And, some of callers are modified by this change.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/compression.c b/fs/btrfs/compression.c
index 992a4b9..41d1d7c 100644
--- a/fs/btrfs/compression.c
+++ b/fs/btrfs/compression.c
@@ -663,8 +663,9 @@
 			atomic_inc(&cb->pending_bios);
 
 			if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
-				btrfs_lookup_bio_sums(root, inode, comp_bio,
-						      sums);
+				ret = btrfs_lookup_bio_sums(root, inode,
+							comp_bio, sums);
+				BUG_ON(ret);
 			}
 			sums += (comp_bio->bi_size + root->sectorsize - 1) /
 				root->sectorsize;
@@ -689,8 +690,10 @@
 	ret = btrfs_bio_wq_end_io(root->fs_info, comp_bio, 0);
 	BUG_ON(ret);
 
-	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM))
-		btrfs_lookup_bio_sums(root, inode, comp_bio, sums);
+	if (!(BTRFS_I(inode)->flags & BTRFS_INODE_NODATASUM)) {
+		ret = btrfs_lookup_bio_sums(root, inode, comp_bio, sums);
+		BUG_ON(ret);
+	}
 
 	ret = btrfs_map_bio(root, READ, comp_bio, mirror_num, 0);
 	BUG_ON(ret);
diff --git a/fs/btrfs/dir-item.c b/fs/btrfs/dir-item.c
index 02c97ad..c62f02f 100644
--- a/fs/btrfs/dir-item.c
+++ b/fs/btrfs/dir-item.c
@@ -151,7 +151,7 @@
 		ret = PTR_ERR(dir_item);
 		if (ret == -EEXIST)
 			goto second_insert;
-		goto out;
+		goto out_free;
 	}
 
 	leaf = path->nodes[0];
@@ -170,7 +170,7 @@
 	/* FIXME, use some real flag for selecting the extra index */
 	if (root == root->fs_info->tree_root) {
 		ret = 0;
-		goto out;
+		goto out_free;
 	}
 	btrfs_release_path(root, path);
 
@@ -180,7 +180,7 @@
 					name, name_len);
 	if (IS_ERR(dir_item)) {
 		ret2 = PTR_ERR(dir_item);
-		goto out;
+		goto out_free;
 	}
 	leaf = path->nodes[0];
 	btrfs_cpu_key_to_disk(&disk_key, location);
@@ -192,7 +192,9 @@
 	name_ptr = (unsigned long)(dir_item + 1);
 	write_extent_buffer(leaf, name, name_ptr, name_len);
 	btrfs_mark_buffer_dirty(leaf);
-out:
+
+out_free:
+
 	btrfs_free_path(path);
 	if (ret)
 		return ret;
diff --git a/fs/btrfs/file-item.c b/fs/btrfs/file-item.c
index a2134195..a6a9d4e 100644
--- a/fs/btrfs/file-item.c
+++ b/fs/btrfs/file-item.c
@@ -170,6 +170,8 @@
 	struct extent_io_tree *io_tree = &BTRFS_I(inode)->io_tree;
 
 	path = btrfs_alloc_path();
+	if (!path)
+		return -ENOMEM;
 	if (bio->bi_size > PAGE_CACHE_SIZE * 8)
 		path->reada = 2;
 
diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index f739b25..04e9fff 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1467,8 +1467,11 @@
 		if (bio_flags & EXTENT_BIO_COMPRESSED) {
 			return btrfs_submit_compressed_read(inode, bio,
 						    mirror_num, bio_flags);
-		} else if (!skip_sum)
-			btrfs_lookup_bio_sums(root, inode, bio, NULL);
+		} else if (!skip_sum) {
+			ret = btrfs_lookup_bio_sums(root, inode, bio, NULL);
+			if (ret)
+				return ret;
+		}
 		goto mapit;
 	} else if (!skip_sum) {
 		/* csum items have already been cloned */
@@ -1903,10 +1906,10 @@
 	else
 		rw = READ;
 
-	BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
+	ret = BTRFS_I(inode)->io_tree.ops->submit_bio_hook(inode, rw, bio,
 						      failrec->last_mirror,
 						      failrec->bio_flags, 0);
-	return 0;
+	return ret;
 }
 
 /*
@@ -5943,9 +5946,12 @@
 				   __btrfs_submit_bio_start_direct_io,
 				   __btrfs_submit_bio_done);
 		goto err;
-	} else if (!skip_sum)
-		btrfs_lookup_bio_sums_dio(root, inode, bio,
+	} else if (!skip_sum) {
+		ret = btrfs_lookup_bio_sums_dio(root, inode, bio,
 					  file_offset, csums);
+		if (ret)
+			goto err;
+	}
 
 	ret = btrfs_map_bio(root, rw, bio, 0, 1);
 err: