raid5: initialize the stripe_head embeeded bios as needed

Use bio_init to initialize the bios when needed to the full state
instead of a partial initialization plus later setting of dev and op
and bio_reset.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Song Liu <song@kernel.org>

diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 8891aab..8bd5f06 100644 (file)
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -1060,6 +1060,7 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
        int i, disks = sh->disks;
        struct stripe_head *head_sh = sh;
        struct bio_list pending_bios = BIO_EMPTY_LIST;
+       struct r5dev *dev;
        bool should_defer;
 
        might_sleep();
@@ -1094,8 +1095,9 @@ static void ops_run_io(struct stripe_head *sh, struct stripe_head_state *s)
                        op_flags |= REQ_SYNC;
 
 again:
-               bi = &sh->dev[i].req;
-               rbi = &sh->dev[i].rreq; /* For writing to replacement */
+               dev = &sh->dev[i];
+               bi = &dev->req;
+               rbi = &dev->rreq; /* For writing to replacement */
 
                rcu_read_lock();
                rrdev = rcu_dereference(conf->disks[i].replacement);
@@ -1171,8 +1173,7 @@ again:
 
                        set_bit(STRIPE_IO_STARTED, &sh->state);
 
-                       bio_set_dev(bi, rdev->bdev);
-                       bio_set_op_attrs(bi, op, op_flags);
+                       bio_init(bi, rdev->bdev, &dev->vec, 1, op | op_flags);
                        bi->bi_end_io = op_is_write(op)
                                ? raid5_end_write_request
                                : raid5_end_read_request;
@@ -1238,8 +1239,7 @@ again:
 
                        set_bit(STRIPE_IO_STARTED, &sh->state);
 
-                       bio_set_dev(rbi, rrdev->bdev);
-                       bio_set_op_attrs(rbi, op, op_flags);
+                       bio_init(rbi, rrdev->bdev, &dev->rvec, 1, op | op_flags);
                        BUG_ON(!op_is_write(op));
                        rbi->bi_end_io = raid5_end_write_request;
                        rbi->bi_private = sh;
@@ -2294,7 +2294,6 @@ static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp,
        int disks, struct r5conf *conf)
 {
        struct stripe_head *sh;
-       int i;
 
        sh = kmem_cache_zalloc(sc, gfp);
        if (sh) {
@@ -2307,12 +2306,6 @@ static struct stripe_head *alloc_stripe(struct kmem_cache *sc, gfp_t gfp,
                atomic_set(&sh->count, 1);
                sh->raid_conf = conf;
                sh->log_start = MaxSector;
-               for (i = 0; i < disks; i++) {
-                       struct r5dev *dev = &sh->dev[i];
-
-                       bio_init(&dev->req, NULL, &dev->vec, 1, 0);
-                       bio_init(&dev->rreq, NULL, &dev->rvec, 1, 0);
-               }
 
                if (raid5_has_ppl(conf)) {
                        sh->ppl_page = alloc_page(gfp);
@@ -2677,7 +2670,6 @@ static void raid5_end_read_request(struct bio * bi)
                (unsigned long long)sh->sector, i, atomic_read(&sh->count),
                bi->bi_status);
        if (i == disks) {
-               bio_reset(bi, NULL, 0);
                BUG();
                return;
        }
@@ -2785,7 +2777,7 @@ static void raid5_end_read_request(struct bio * bi)
                }
        }
        rdev_dec_pending(rdev, conf->mddev);
-       bio_reset(bi, NULL, 0);
+       bio_uninit(bi);
        clear_bit(R5_LOCKED, &sh->dev[i].flags);
        set_bit(STRIPE_HANDLE, &sh->state);
        raid5_release_stripe(sh);
@@ -2823,7 +2815,6 @@ static void raid5_end_write_request(struct bio *bi)
                (unsigned long long)sh->sector, i, atomic_read(&sh->count),
                bi->bi_status);
        if (i == disks) {
-               bio_reset(bi, NULL, 0);
                BUG();
                return;
        }
@@ -2860,7 +2851,7 @@ static void raid5_end_write_request(struct bio *bi)
        if (sh->batch_head && bi->bi_status && !replacement)
                set_bit(STRIPE_BATCH_ERR, &sh->batch_head->state);
 
-       bio_reset(bi, NULL, 0);
+       bio_uninit(bi);
        if (!test_and_clear_bit(R5_DOUBLE_LOCKED, &sh->dev[i].flags))
                clear_bit(R5_LOCKED, &sh->dev[i].flags);
        set_bit(STRIPE_HANDLE, &sh->state);