dm: add local variables to clone_endio and __map_bio

Avoid redundant dereferences in both functions.

Signed-off-by: Mike Snitzer <snitzer@kernel.org>

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 34d457cfcb363f1e17ce264d01ccefda71fdebdf..152545ef00fa40bc65cf087329fdc93f8c17ffbe 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -976,11 +976,12 @@ static bool swap_bios_limit(struct dm_target *ti, struct bio *bio)
 static void clone_endio(struct bio *bio)
 {
        blk_status_t error = bio->bi_status;
+       struct request_queue *q = bio->bi_bdev->bd_disk->queue;
        struct dm_target_io *tio = clone_to_tio(bio);
+       struct dm_target *ti = tio->ti;
+       dm_endio_fn endio = ti->type->end_io;
        struct dm_io *io = tio->io;
-       struct mapped_device *md = tio->io->md;
-       dm_endio_fn endio = tio->ti->type->end_io;
-       struct request_queue *q = bio->bi_bdev->bd_disk->queue;
+       struct mapped_device *md = io->md;
 
        if (unlikely(error == BLK_STS_TARGET)) {
                if (bio_op(bio) == REQ_OP_DISCARD &&
@@ -995,7 +996,7 @@ static void clone_endio(struct bio *bio)
                dm_zone_endio(io, bio);
 
        if (endio) {
-               int r = endio(tio->ti, bio, &error);
+               int r = endio(ti, bio, &error);
                switch (r) {
                case DM_ENDIO_REQUEUE:
                        /*
@@ -1019,10 +1020,8 @@ static void clone_endio(struct bio *bio)
                }
        }
 
-       if (unlikely(swap_bios_limit(tio->ti, bio))) {
-               struct mapped_device *md = io->md;
+       if (unlikely(swap_bios_limit(ti, bio)))
                up(&md->swap_bios_semaphore);
-       }
 
        free_tio(bio);
        dm_io_dec_pending(io, error);
@@ -1263,9 +1262,10 @@ static noinline void __set_swap_bios_limit(struct mapped_device *md, int latch)
 static void __map_bio(struct bio *clone)
 {
        struct dm_target_io *tio = clone_to_tio(clone);
-       int r;
-       struct dm_io *io = tio->io;
        struct dm_target *ti = tio->ti;
+       struct dm_io *io = tio->io;
+       struct mapped_device *md = io->md;
+       int r;
 
        clone->bi_end_io = clone_endio;
 
@@ -1276,7 +1276,6 @@ static void __map_bio(struct bio *clone)
        tio->old_sector = clone->bi_iter.bi_sector;
 
        if (unlikely(swap_bios_limit(ti, clone))) {
-               struct mapped_device *md = io->md;
                int latch = get_swap_bios();
                if (unlikely(latch != md->swap_bios))
                        __set_swap_bios_limit(md, latch);
@@ -1288,7 +1287,7 @@ static void __map_bio(struct bio *clone)
         * on zoned target. In this case, dm_zone_map_bio() calls the target
         * map operation.
         */
-       if (unlikely(dm_emulate_zone_append(io->md)))
+       if (unlikely(dm_emulate_zone_append(md)))
                r = dm_zone_map_bio(tio);
        else
                r = ti->type->map(ti, clone);
@@ -1304,14 +1303,14 @@ static void __map_bio(struct bio *clone)
                 * the bio has been remapped so dispatch it, but defer
                 * dm_start_io_acct() until after possible bio_split().
                 */
-               __dm_submit_bio_remap(clone, disk_devt(io->md->disk),
+               __dm_submit_bio_remap(clone, disk_devt(md->disk),
                                      tio->old_sector);
                dm_io_set_flag(io, DM_IO_START_ACCT);
                break;
        case DM_MAPIO_KILL:
        case DM_MAPIO_REQUEUE:
                if (unlikely(swap_bios_limit(ti, clone)))
-                       up(&io->md->swap_bios_semaphore);
+                       up(&md->swap_bios_semaphore);
                free_tio(clone);
                if (r == DM_MAPIO_KILL)
                        dm_io_dec_pending(io, BLK_STS_IOERR);