btrfs: refactor error handling in btrfs_submit_bio

Add a bbio local variable and to prepare for calling functions that
return a blk_status_t, rename the existing int used for error handling
so that ret can be reused for the blk_status_t, and a label that can be
reused for failing the passed in bio.

Reviewed-by: Anand Jain <anand.jain@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/bio.c b/fs/btrfs/bio.c
index b06bdf28abd7c5af8428ff465b8f638312b56b3e..088817618f57457ce59f7f233af8c027ef6d3c62 100644 (file)
--- a/fs/btrfs/bio.c
+++ b/fs/btrfs/bio.c
@@ -230,20 +230,21 @@ static void btrfs_submit_mirrored_bio(struct btrfs_io_context *bioc, int dev_nr)
 
 void btrfs_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio, int mirror_num)
 {
+       struct btrfs_bio *bbio = btrfs_bio(bio);
        u64 logical = bio->bi_iter.bi_sector << 9;
        u64 length = bio->bi_iter.bi_size;
        u64 map_length = length;
        struct btrfs_io_context *bioc = NULL;
        struct btrfs_io_stripe smap;
-       int ret;
+       blk_status_t ret;
+       int error;
 
        btrfs_bio_counter_inc_blocked(fs_info);
-       ret = __btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length,
-                               &bioc, &smap, &mirror_num, 1);
-       if (ret) {
-               btrfs_bio_counter_dec(fs_info);
-               btrfs_bio_end_io(btrfs_bio(bio), errno_to_blk_status(ret));
-               return;
+       error = __btrfs_map_block(fs_info, btrfs_op(bio), logical, &map_length,
+                                 &bioc, &smap, &mirror_num, 1);
+       if (error) {
+               ret = errno_to_blk_status(error);
+               goto fail;
        }
 
        if (map_length < length) {
@@ -255,8 +256,8 @@ void btrfs_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio, int mirror
 
        if (!bioc) {
                /* Single mirror read/write fast path */
-               btrfs_bio(bio)->mirror_num = mirror_num;
-               btrfs_bio(bio)->device = smap.dev;
+               bbio->mirror_num = mirror_num;
+               bbio->device = smap.dev;
                bio->bi_iter.bi_sector = smap.physical >> SECTOR_SHIFT;
                bio->bi_private = fs_info;
                bio->bi_end_io = btrfs_simple_end_io;
@@ -278,6 +279,11 @@ void btrfs_submit_bio(struct btrfs_fs_info *fs_info, struct bio *bio, int mirror
                for (dev_nr = 0; dev_nr < total_devs; dev_nr++)
                        btrfs_submit_mirrored_bio(bioc, dev_nr);
        }
+       return;
+
+fail:
+       btrfs_bio_counter_dec(fs_info);
+       btrfs_bio_end_io(bbio, ret);
 }
 
 /*