dm: change ->end_io calling convention

Turn the error paramter into a pointer so that target drivers can change
the value, and make sure only DM_ENDIO_* values are returned from the
methods.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Signed-off-by: Jens Axboe <axboe@fb.com>

diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c
index d682a0511381aad0cadb7ab1f4eae9f815639aa1..c48612e6d52543555f98883c5710e2e00d1e1113 100644 (file)
--- a/drivers/md/dm-cache-target.c
+++ b/drivers/md/dm-cache-target.c
@@ -2820,7 +2820,7 @@ static int cache_map(struct dm_target *ti, struct bio *bio)
        return r;
 }
 
-static int cache_end_io(struct dm_target *ti, struct bio *bio, int error)
+static int cache_end_io(struct dm_target *ti, struct bio *bio, int *error)
 {
        struct cache *cache = ti->private;
        unsigned long flags;
@@ -2838,7 +2838,7 @@ static int cache_end_io(struct dm_target *ti, struct bio *bio, int error)
        bio_drop_shared_lock(cache, bio);
        accounted_complete(cache, bio);
 
-       return 0;
+       return DM_ENDIO_DONE;
 }
 
 static int write_dirty_bitset(struct cache *cache)

diff --git a/drivers/md/dm-flakey.c b/drivers/md/dm-flakey.c
index e8f093b323cef7cd6ed88830a475d256e1c2439d..c9539917a59b07c6d9384de82acb450fff2b6b9c 100644 (file)
--- a/drivers/md/dm-flakey.c
+++ b/drivers/md/dm-flakey.c
@@ -358,12 +358,12 @@ map_bio:
        return DM_MAPIO_REMAPPED;
 }
 
-static int flakey_end_io(struct dm_target *ti, struct bio *bio, int error)
+static int flakey_end_io(struct dm_target *ti, struct bio *bio, int *error)
 {
        struct flakey_c *fc = ti->private;
        struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data));
 
-       if (!error && pb->bio_submitted && (bio_data_dir(bio) == READ)) {
+       if (!*error && pb->bio_submitted && (bio_data_dir(bio) == READ)) {
                if (fc->corrupt_bio_byte && (fc->corrupt_bio_rw == READ) &&
                    all_corrupt_bio_flags_match(bio, fc)) {
                        /*
@@ -377,11 +377,11 @@ static int flakey_end_io(struct dm_target *ti, struct bio *bio, int error)
                         * Error read during the down_interval if drop_writes
                         * and error_writes were not configured.
                         */
-                       return -EIO;
+                       *error = -EIO;
                }
        }
 
-       return error;
+       return DM_ENDIO_DONE;
 }
 
 static void flakey_status(struct dm_target *ti, status_type_t type,

diff --git a/drivers/md/dm-log-writes.c b/drivers/md/dm-log-writes.c
index e42264706c5993ddb6dd7af94797474ee3c73e96..cc57c7fa1268ab452b2864f572a3a6dca57d7c82 100644 (file)
--- a/drivers/md/dm-log-writes.c
+++ b/drivers/md/dm-log-writes.c
@@ -664,7 +664,7 @@ map_bio:
        return DM_MAPIO_REMAPPED;
 }
 
-static int normal_end_io(struct dm_target *ti, struct bio *bio, int error)
+static int normal_end_io(struct dm_target *ti, struct bio *bio, int *error)
 {
        struct log_writes_c *lc = ti->private;
        struct per_bio_data *pb = dm_per_bio_data(bio, sizeof(struct per_bio_data));
@@ -686,7 +686,7 @@ static int normal_end_io(struct dm_target *ti, struct bio *bio, int error)
                spin_unlock_irqrestore(&lc->blocks_lock, flags);
        }
 
-       return error;
+       return DM_ENDIO_DONE;
 }
 
 /*

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index bf6e49c780d58c78fae3b6146fac1bf1ebb453e9..ceeeb495d01c73d69de3952c05733f0b12b63159 100644 (file)
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1517,14 +1517,15 @@ static int multipath_end_io(struct dm_target *ti, struct request *clone,
        return r;
 }
 
-static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, int error)
+static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, int *error)
 {
        struct multipath *m = ti->private;
        struct dm_mpath_io *mpio = get_mpio_from_bio(clone);
        struct pgpath *pgpath = mpio->pgpath;
        unsigned long flags;
+       int r = DM_ENDIO_DONE;
 
-       if (!error || noretry_error(error))
+       if (!*error || noretry_error(*error))
                goto done;
 
        if (pgpath)
@@ -1533,7 +1534,7 @@ static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, int err
        if (atomic_read(&m->nr_valid_paths) == 0 &&
            !test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
                dm_report_EIO(m);
-               error = -EIO;
+               *error = -EIO;
                goto done;
        }
 
@@ -1546,7 +1547,7 @@ static int multipath_end_io_bio(struct dm_target *ti, struct bio *clone, int err
        if (!test_bit(MPATHF_QUEUE_IO, &m->flags))
                queue_work(kmultipathd, &m->process_queued_bios);
 
-       error = DM_ENDIO_INCOMPLETE;
+       r = DM_ENDIO_INCOMPLETE;
 done:
        if (pgpath) {
                struct path_selector *ps = &pgpath->pg->ps;
@@ -1555,7 +1556,7 @@ done:
                        ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
        }
 
-       return error;
+       return r;
 }
 
 /*

diff --git a/drivers/md/dm-raid1.c b/drivers/md/dm-raid1.c
index d9c0c6a77eb5872ae0ce143fbb09928727459745..77bcf50ce75fb319a22b957c56a8aedb3a1333e6 100644 (file)
--- a/drivers/md/dm-raid1.c
+++ b/drivers/md/dm-raid1.c
@@ -1236,7 +1236,7 @@ static int mirror_map(struct dm_target *ti, struct bio *bio)
        return DM_MAPIO_REMAPPED;
 }
 
-static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error)
+static int mirror_end_io(struct dm_target *ti, struct bio *bio, int *error)
 {
        int rw = bio_data_dir(bio);
        struct mirror_set *ms = (struct mirror_set *) ti->private;
@@ -1252,16 +1252,16 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error)
                if (!(bio->bi_opf & REQ_PREFLUSH) &&
                    bio_op(bio) != REQ_OP_DISCARD)
                        dm_rh_dec(ms->rh, bio_record->write_region);
-               return error;
+               return DM_ENDIO_DONE;
        }
 
-       if (error == -EOPNOTSUPP)
-               return error;
+       if (*error == -EOPNOTSUPP)
+               return DM_ENDIO_DONE;
 
        if (bio->bi_opf & REQ_RAHEAD)
-               return error;
+               return DM_ENDIO_DONE;
 
-       if (unlikely(error)) {
+       if (unlikely(*error)) {
                m = bio_record->m;
 
                DMERR("Mirror read failed from %s. Trying alternative device.",
@@ -1285,7 +1285,7 @@ static int mirror_end_io(struct dm_target *ti, struct bio *bio, int error)
                DMERR("All replicated volumes dead, failing I/O");
        }
 
-       return error;
+       return DM_ENDIO_DONE;
 }
 
 static void mirror_presuspend(struct dm_target *ti)

diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c
index 5a7f73f9a6fb135dc68230fe4c065fec058dbda6..79a845798e2f64c64d9d1b1ef2b1bdcdead882d1 100644 (file)
--- a/drivers/md/dm-snap.c
+++ b/drivers/md/dm-snap.c
@@ -1851,14 +1851,14 @@ out_unlock:
        return r;
 }
 
-static int snapshot_end_io(struct dm_target *ti, struct bio *bio, int error)
+static int snapshot_end_io(struct dm_target *ti, struct bio *bio, int *error)
 {
        struct dm_snapshot *s = ti->private;
 
        if (is_bio_tracked(bio))
                stop_tracking_chunk(s, bio);
 
-       return 0;
+       return DM_ENDIO_DONE;
 }
 
 static void snapshot_merge_presuspend(struct dm_target *ti)

diff --git a/drivers/md/dm-stripe.c b/drivers/md/dm-stripe.c
index 780e95889a7c425dcb20bf21947f408967b27ad0..49888bc2c909108bf94355ec7175bc62a8d59d4c 100644 (file)
--- a/drivers/md/dm-stripe.c
+++ b/drivers/md/dm-stripe.c
@@ -375,20 +375,20 @@ static void stripe_status(struct dm_target *ti, status_type_t type,
        }
 }
 
-static int stripe_end_io(struct dm_target *ti, struct bio *bio, int error)
+static int stripe_end_io(struct dm_target *ti, struct bio *bio, int *error)
 {
        unsigned i;
        char major_minor[16];
        struct stripe_c *sc = ti->private;
 
-       if (!error)
-               return 0; /* I/O complete */
+       if (!*error)
+               return DM_ENDIO_DONE; /* I/O complete */
 
        if (bio->bi_opf & REQ_RAHEAD)
-               return error;
+               return DM_ENDIO_DONE;
 
-       if (error == -EOPNOTSUPP)
-               return error;
+       if (*error == -EOPNOTSUPP)
+               return DM_ENDIO_DONE;
 
        memset(major_minor, 0, sizeof(major_minor));
        sprintf(major_minor, "%d:%d",
@@ -409,7 +409,7 @@ static int stripe_end_io(struct dm_target *ti, struct bio *bio, int error)
                                schedule_work(&sc->trigger_event);
                }
 
-       return error;
+       return DM_ENDIO_DONE;
 }
 
 static int stripe_iterate_devices(struct dm_target *ti,

diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 17ad50daed08ef5022b8648ef2e8701208c85a9d..22b1a64c44b7a23682a2f6eb88385e011e209e68 100644 (file)
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -4177,7 +4177,7 @@ static int thin_map(struct dm_target *ti, struct bio *bio)
        return thin_bio_map(ti, bio);
 }
 
-static int thin_endio(struct dm_target *ti, struct bio *bio, int err)
+static int thin_endio(struct dm_target *ti, struct bio *bio, int *err)
 {
        unsigned long flags;
        struct dm_thin_endio_hook *h = dm_per_bio_data(bio, sizeof(struct dm_thin_endio_hook));
@@ -4212,7 +4212,7 @@ static int thin_endio(struct dm_target *ti, struct bio *bio, int err)
        if (h->cell)
                cell_defer_no_holder(h->tc, h->cell);
 
-       return 0;
+       return DM_ENDIO_DONE;
 }
 
 static void thin_presuspend(struct dm_target *ti)

diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index 499f8209bacf9484c03a777c36f592b23865b8c1..7a7047211c6436faa11fbfe1b30d2f69bda25f53 100644 (file)
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -845,24 +845,7 @@ static void clone_endio(struct bio *bio)
        struct mapped_device *md = tio->io->md;
        dm_endio_fn endio = tio->ti->type->end_io;
 
-       if (endio) {
-               r = endio(tio->ti, bio, error);
-               if (r < 0 || r == DM_ENDIO_REQUEUE)
-                       /*
-                        * error and requeue request are handled
-                        * in dec_pending().
-                        */
-                       error = r;
-               else if (r == DM_ENDIO_INCOMPLETE)
-                       /* The target will handle the io */
-                       return;
-               else if (r) {
-                       DMWARN("unimplemented target endio return value: %d", r);
-                       BUG();
-               }
-       }
-
-       if (unlikely(r == -EREMOTEIO)) {
+       if (unlikely(error == -EREMOTEIO)) {
                if (bio_op(bio) == REQ_OP_WRITE_SAME &&
                    !bdev_get_queue(bio->bi_bdev)->limits.max_write_same_sectors)
                        disable_write_same(md);
@@ -871,6 +854,23 @@ static void clone_endio(struct bio *bio)
                        disable_write_zeroes(md);
        }
 
+       if (endio) {
+               r = endio(tio->ti, bio, &error);
+               switch (r) {
+               case DM_ENDIO_REQUEUE:
+                       error = DM_ENDIO_REQUEUE;
+                       /*FALLTHRU*/
+               case DM_ENDIO_DONE:
+                       break;
+               case DM_ENDIO_INCOMPLETE:
+                       /* The target will handle the io */
+                       return;
+               default:
+                       DMWARN("unimplemented target endio return value: %d", r);
+                       BUG();
+               }
+       }
+
        free_tio(tio);
        dec_pending(io, error);
 }

diff --git a/include/linux/device-mapper.h b/include/linux/device-mapper.h
index f4c639c0c362fd4c5106c5a6d2d6ceae1f3c795a..dec227acc13b5f241dcc077bb66568a14e766389 100644 (file)
--- a/include/linux/device-mapper.h
+++ b/include/linux/device-mapper.h
@@ -72,7 +72,7 @@ typedef void (*dm_release_clone_request_fn) (struct request *clone);
  * 2   : The target wants to push back the io
  */
 typedef int (*dm_endio_fn) (struct dm_target *ti,
-                           struct bio *bio, int error);
+                           struct bio *bio, int *error);
 typedef int (*dm_request_endio_fn) (struct dm_target *ti,
                                    struct request *clone, int error,
                                    union map_info *map_context);