md/raid1: factor out common bio handling code

When normal-write and sync-read/write bio completes, we should
find out the disk number the bio belongs to. Factor those common
code out to a separate function.

Signed-off-by: Namhyung Kim <namhyung@gmail.com>
Signed-off-by: NeilBrown <neilb@suse.de>

1 files changed, 24 insertions, 20 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index d9587dffe533..a0c02fb8af2a 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -268,6 +268,24 @@ static inline void update_head_pos(int disk, r1bio_t *r1_bio)
                 r1_bio->sector + (r1_bio->sectors);
 }
 
+/*
+ * Find the disk number which triggered given bio
+ */
+static int find_bio_disk(r1bio_t *r1_bio, struct bio *bio)
+{
+        int mirror;
+        int raid_disks = r1_bio->mddev->raid_disks;
+
+        for (mirror = 0; mirror < raid_disks; mirror++)
+                if (r1_bio->bios[mirror] == bio)
+                        break;
+
+        BUG_ON(mirror == raid_disks);
+        update_head_pos(mirror, r1_bio);
+
+        return mirror;
+}
+
 static void raid1_end_read_request(struct bio *bio, int error)
 {
         int uptodate = test_bit(BIO_UPTODATE, &bio->bi_flags);
@@ -361,10 +379,7 @@ static void raid1_end_write_request(struct bio *bio, int error)
         conf_t *conf = r1_bio->mddev->private;
         struct bio *to_put = NULL;
 
-
-        for (mirror = 0; mirror < conf->raid_disks; mirror++)
-                if (r1_bio->bios[mirror] == bio)
-                        break;
+        mirror = find_bio_disk(r1_bio, bio);
 
         /*
          * 'one mirror IO has finished' event handler:
@@ -400,8 +415,6 @@ static void raid1_end_write_request(struct bio *bio, int error)
                 }
         }
 
-        update_head_pos(mirror, r1_bio);
-
         if (behind) {
                 if (test_bit(WriteMostly, &conf->mirrors[mirror].rdev->flags))
                         atomic_dec(&r1_bio->behind_remaining);
@@ -1344,13 +1357,10 @@ abort:
 static void end_sync_read(struct bio *bio, int error)
 {
         r1bio_t *r1_bio = bio->bi_private;
-        int i;
 
-        for (i=r1_bio->mddev->raid_disks; i--; )
-                if (r1_bio->bios[i] == bio)
-                        break;
-        BUG_ON(i < 0);
-        update_head_pos(i, r1_bio);
+        /* this will call update_head_pos() */
+        find_bio_disk(r1_bio, bio);
+
         /*
          * we have read a block, now it needs to be re-written,
          * or re-read if the read failed.
@@ -1369,16 +1379,12 @@ static void end_sync_write(struct bio *bio, int error)
         r1bio_t *r1_bio = bio->bi_private;
         mddev_t *mddev = r1_bio->mddev;
         conf_t *conf = mddev->private;
-        int i;
         int mirror=0;
         sector_t first_bad;
         int bad_sectors;
 
-        for (i = 0; i < conf->raid_disks; i++)
-                if (r1_bio->bios[i] == bio) {
-                        mirror = i;
-                        break;
-                }
+        mirror = find_bio_disk(r1_bio, bio);
+
         if (!uptodate) {
                 sector_t sync_blocks = 0;
                 sector_t s = r1_bio->sector;
@@ -1404,8 +1410,6 @@ static void end_sync_write(struct bio *bio, int error)
                 )
                 set_bit(R1BIO_MadeGood, &r1_bio->state);
 
-        update_head_pos(mirror, r1_bio);
-
         if (atomic_dec_and_test(&r1_bio->remaining)) {
                 int s = r1_bio->sectors;
                 if (test_bit(R1BIO_MadeGood, &r1_bio->state) ||