1 files changed, 19 insertions, 17 deletions

diff --git a/fs/btrfs/volumes.c b/fs/btrfs/volumes.c
index ffeed6d6326..c83b24251e5 100644
--- a/fs/btrfs/volumes.c
+++ b/fs/btrfs/volumes.c
@@ -2543,9 +2543,6 @@ static int btrfs_relocate_chunk(struct btrfs_root *root,
 	remove_extent_mapping(em_tree, em);
 	write_unlock(&em_tree->lock);
 
-	kfree(map);
-	em->bdev = NULL;
-
 	/* once for the tree */
 	free_extent_map(em);
 	/* once for us */
@@ -4301,9 +4298,11 @@ static int __btrfs_alloc_chunk(struct btrfs_trans_handle *trans,
 
 	em = alloc_extent_map();
 	if (!em) {
+		kfree(map);
 		ret = -ENOMEM;
 		goto error;
 	}
+	set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
 	em->bdev = (struct block_device *)map;
 	em->start = start;
 	em->len = num_bytes;
@@ -4346,7 +4345,6 @@ error_del_extent:
 	/* One for the tree reference */
 	free_extent_map(em);
 error:
-	kfree(map);
 	kfree(devices_info);
 	return ret;
 }
@@ -4558,7 +4556,6 @@ void btrfs_mapping_tree_free(struct btrfs_mapping_tree *tree)
 		write_unlock(&tree->map_tree.lock);
 		if (!em)
 			break;
-		kfree(em->bdev);
 		/* once for us */
 		free_extent_map(em);
 		/* once for the tree */
@@ -5362,6 +5359,15 @@ int btrfs_rmap_block(struct btrfs_mapping_tree *map_tree,
 	return 0;
 }
 
+static inline void btrfs_end_bbio(struct btrfs_bio *bbio, struct bio *bio, int err)
+{
+	if (likely(bbio->flags & BTRFS_BIO_ORIG_BIO_SUBMITTED))
+		bio_endio_nodec(bio, err);
+	else
+		bio_endio(bio, err);
+	kfree(bbio);
+}
+
 static void btrfs_end_bio(struct bio *bio, int err)
 {
 	struct btrfs_bio *bbio = bio->bi_private;
@@ -5402,12 +5408,6 @@ static void btrfs_end_bio(struct bio *bio, int err)
 			bio = bbio->orig_bio;
 		}
 
- 		/*
-		 * We have original bio now. So increment bi_remaining to
-		 * account for it in endio
-		 */
-		atomic_inc(&bio->bi_remaining);
-
 		bio->bi_private = bbio->private;
 		bio->bi_end_io = bbio->end_io;
 		btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
@@ -5424,9 +5424,8 @@ static void btrfs_end_bio(struct bio *bio, int err)
 			set_bit(BIO_UPTODATE, &bio->bi_flags);
 			err = 0;
 		}
-		kfree(bbio);
 
-		bio_endio(bio, err);
+		btrfs_end_bbio(bbio, bio, err);
 	} else if (!is_orig_bio) {
 		bio_put(bio);
 	}
@@ -5589,12 +5588,15 @@ static void bbio_error(struct btrfs_bio *bbio, struct bio *bio, u64 logical)
 {
 	atomic_inc(&bbio->error);
 	if (atomic_dec_and_test(&bbio->stripes_pending)) {
+		/* Shoud be the original bio. */
+		WARN_ON(bio != bbio->orig_bio);
+
 		bio->bi_private = bbio->private;
 		bio->bi_end_io = bbio->end_io;
 		btrfs_io_bio(bio)->mirror_num = bbio->mirror_num;
 		bio->bi_iter.bi_sector = logical >> 9;
-		kfree(bbio);
-		bio_endio(bio, -EIO);
+
+		btrfs_end_bbio(bbio, bio, -EIO);
 	}
 }
 
@@ -5681,6 +5683,7 @@ int btrfs_map_bio(struct btrfs_root *root, int rw, struct bio *bio,
 			BUG_ON(!bio); /* -ENOMEM */
 		} else {
 			bio = first_bio;
+			bbio->flags |= BTRFS_BIO_ORIG_BIO_SUBMITTED;
 		}
 
 		submit_stripe_bio(root, bbio, bio,
@@ -5822,6 +5825,7 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
 		return -ENOMEM;
 	}
 
+	set_bit(EXTENT_FLAG_FS_MAPPING, &em->flags);
 	em->bdev = (struct block_device *)map;
 	em->start = logical;
 	em->len = length;
@@ -5846,7 +5850,6 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
 		map->stripes[i].dev = btrfs_find_device(root->fs_info, devid,
 							uuid, NULL);
 		if (!map->stripes[i].dev && !btrfs_test_opt(root, DEGRADED)) {
-			kfree(map);
 			free_extent_map(em);
 			return -EIO;
 		}
@@ -5854,7 +5857,6 @@ static int read_one_chunk(struct btrfs_root *root, struct btrfs_key *key,
 			map->stripes[i].dev =
 				add_missing_dev(root, devid, uuid);
 			if (!map->stripes[i].dev) {
-				kfree(map);
 				free_extent_map(em);
 				return -EIO;
 			}