raid1: Refactor narrow_write_error() to not use bi_idx

More bi_idx removal. This code was just open coding bio_clone(). This
could probably be further improved by using bio_advance() instead of
skipping over null pages, but that'd be a larger rework.

Signed-off-by: Kent Overstreet <koverstreet@google.com>
CC: Jens Axboe <axboe@kernel.dk>
CC: NeilBrown <neilb@suse.de>

1 files changed, 18 insertions, 18 deletions

diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index bb5ec7710c00..b36231866336 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -2063,8 +2063,6 @@ static int narrow_write_error(struct r1bio *r1_bio, int i)
         struct mddev *mddev = r1_bio->mddev;
         struct r1conf *conf = mddev->private;
         struct md_rdev *rdev = conf->mirrors[i].rdev;
-        int vcnt, idx;
-        struct bio_vec *vec;
 
         /* bio has the data to be written to device 'i' where
          * we just recently had a write error.
@@ -2092,30 +2090,32 @@ static int narrow_write_error(struct r1bio *r1_bio, int i)
                    & ~(sector_t)(block_sectors - 1))
                 - sector;
 
-        if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
-                vcnt = r1_bio->behind_page_count;
-                vec = r1_bio->behind_bvecs;
-                idx = 0;
-                while (vec[idx].bv_page == NULL)
-                        idx++;
-        } else {
-                vcnt = r1_bio->master_bio->bi_vcnt;
-                vec = r1_bio->master_bio->bi_io_vec;
-                idx = r1_bio->master_bio->bi_idx;
-        }
         while (sect_to_write) {
                 struct bio *wbio;
                 if (sectors > sect_to_write)
                         sectors = sect_to_write;
                 /* Write at 'sector' for 'sectors'*/
 
-                wbio = bio_alloc_mddev(GFP_NOIO, vcnt, mddev);
-                memcpy(wbio->bi_io_vec, vec, vcnt * sizeof(struct bio_vec));
-                wbio->bi_sector = r1_bio->sector;
+                if (test_bit(R1BIO_BehindIO, &r1_bio->state)) {
+                        unsigned vcnt = r1_bio->behind_page_count;
+                        struct bio_vec *vec = r1_bio->behind_bvecs;
+
+                        while (!vec->bv_page) {
+                                vec++;
+                                vcnt--;
+                        }
+
+                        wbio = bio_alloc_mddev(GFP_NOIO, vcnt, mddev);
+                        memcpy(wbio->bi_io_vec, vec, vcnt * sizeof(struct bio_vec));
+
+                        wbio->bi_vcnt = vcnt;
+                } else {
+                        wbio = bio_clone_mddev(r1_bio->master_bio, GFP_NOIO, mddev);
+                }
+
                 wbio->bi_rw = WRITE;
-                wbio->bi_vcnt = vcnt;
+                wbio->bi_sector = r1_bio->sector;
                 wbio->bi_size = r1_bio->sectors << 9;
-                wbio->bi_idx = idx;
 
                 md_trim_bio(wbio, sector - r1_bio->sector, sectors);
                 wbio->bi_sector += rdev->data_offset;