[dm-devel] [PATCH 1/4] dm mpath: merge do_end_io into multipath_end_io

[Christoph Hellwig]

This simplifies the I/O completion path a bit.

Signed-off-by: Christoph Hellwig <h...@lst.de>
---
 drivers/md/dm-mpath.c | 53 +++++++++++++++++----------------------------------
 1 file changed, 18 insertions(+), 35 deletions(-)

diff --git a/drivers/md/dm-mpath.c b/drivers/md/dm-mpath.c
index 2950b145443d..1973670ea102 100644
--- a/drivers/md/dm-mpath.c
+++ b/drivers/md/dm-mpath.c
@@ -1473,12 +1473,12 @@ static int noretry_error(int error)
        return 0;
 }
 
-/*
- * end_io handling
- */
-static int do_end_io(struct multipath *m, struct request *clone,
-                    int error, struct dm_mpath_io *mpio)
+static int multipath_end_io(struct dm_target *ti, struct request *clone,
+                           int error, union map_info *map_context)
 {
+       struct dm_mpath_io *mpio = get_mpio(map_context);
+       struct pgpath *pgpath = mpio->pgpath;
+
        /*
         * We don't queue any clone request inside the multipath target
         * during end I/O handling, since those clone requests don't have
@@ -1490,47 +1490,30 @@ static int do_end_io(struct multipath *m, struct 
request *clone,
         * request into dm core, which will remake a clone request and
         * clone bios for it and resubmit it later.
         */
-       int r = DM_ENDIO_REQUEUE;
-
-       if (!error)
-               return 0;       /* I/O complete */
+       if (error && !noretry_error(error)) {
+               struct multipath *m = ti->private;
 
-       if (noretry_error(error))
-               return error;
+               error = DM_ENDIO_REQUEUE;
 
-       if (mpio->pgpath)
-               fail_path(mpio->pgpath);
+               if (pgpath)
+                       fail_path(pgpath);
 
-       if (!atomic_read(&m->nr_valid_paths)) {
-               if (!test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
-                       if (!must_push_back_rq(m))
-                               r = -EIO;
+               if (!atomic_read(&m->nr_valid_paths)) {
+                       if (!test_bit(MPATHF_QUEUE_IF_NO_PATH, &m->flags)) {
+                               if (!must_push_back_rq(m))
+                                       error = -EIO;
+                       }
                }
        }
 
-       return r;
-}
-
-static int multipath_end_io(struct dm_target *ti, struct request *clone,
-                           int error, union map_info *map_context)
-{
-       struct multipath *m = ti->private;
-       struct dm_mpath_io *mpio = get_mpio(map_context);
-       struct pgpath *pgpath;
-       struct path_selector *ps;
-       int r;
-
-       BUG_ON(!mpio);
-
-       r = do_end_io(m, clone, error, mpio);
-       pgpath = mpio->pgpath;
        if (pgpath) {
-               ps = &pgpath->pg->ps;
+               struct path_selector *ps = &pgpath->pg->ps;
+
                if (ps->type->end_io)
                        ps->type->end_io(ps, &pgpath->path, mpio->nr_bytes);
        }
 
-       return r;
+       return error;
 }
 
 static int do_end_io_bio(struct multipath *m, struct bio *clone,
-- 
2.11.0

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