diff options
Diffstat (limited to 'drivers/md/raid1.c')
| -rw-r--r-- | drivers/md/raid1.c | 32 |
1 files changed, 25 insertions, 7 deletions
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c index 3c44c4bb40fc..7dc8026cf6ee 100644 --- a/drivers/md/raid1.c +++ b/drivers/md/raid1.c @@ -1329,6 +1329,7 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, struct raid1_plug_cb *plug = NULL; int first_clone; int max_sectors; + bool write_behind = false; if (mddev_is_clustered(mddev) && md_cluster_ops->area_resyncing(mddev, WRITE, @@ -1381,6 +1382,15 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, max_sectors = r1_bio->sectors; for (i = 0; i < disks; i++) { struct md_rdev *rdev = rcu_dereference(conf->mirrors[i].rdev); + + /* + * The write-behind io is only attempted on drives marked as + * write-mostly, which means we could allocate write behind + * bio later. + */ + if (rdev && test_bit(WriteMostly, &rdev->flags)) + write_behind = true; + if (rdev && unlikely(test_bit(Blocked, &rdev->flags))) { atomic_inc(&rdev->nr_pending); blocked_rdev = rdev; @@ -1454,6 +1464,15 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, goto retry_write; } + /* + * When using a bitmap, we may call alloc_behind_master_bio below. + * alloc_behind_master_bio allocates a copy of the data payload a page + * at a time and thus needs a new bio that can fit the whole payload + * this bio in page sized chunks. + */ + if (write_behind && bitmap) + max_sectors = min_t(int, max_sectors, + BIO_MAX_VECS * (PAGE_SIZE >> 9)); if (max_sectors < bio_sectors(bio)) { struct bio *split = bio_split(bio, max_sectors, GFP_NOIO, &conf->bio_split); @@ -1477,7 +1496,7 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, if (!r1_bio->bios[i]) continue; - if (first_clone) { + if (first_clone && test_bit(WriteMostly, &rdev->flags)) { /* do behind I/O ? * Not if there are too many, or cannot * allocate memory, or a reader on WriteMostly @@ -1510,13 +1529,12 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, r1_bio->bios[i] = mbio; - mbio->bi_iter.bi_sector = (r1_bio->sector + - conf->mirrors[i].rdev->data_offset); - bio_set_dev(mbio, conf->mirrors[i].rdev->bdev); + mbio->bi_iter.bi_sector = (r1_bio->sector + rdev->data_offset); + bio_set_dev(mbio, rdev->bdev); mbio->bi_end_io = raid1_end_write_request; mbio->bi_opf = bio_op(bio) | (bio->bi_opf & (REQ_SYNC | REQ_FUA)); - if (test_bit(FailFast, &conf->mirrors[i].rdev->flags) && - !test_bit(WriteMostly, &conf->mirrors[i].rdev->flags) && + if (test_bit(FailFast, &rdev->flags) && + !test_bit(WriteMostly, &rdev->flags) && conf->raid_disks - mddev->degraded > 1) mbio->bi_opf |= MD_FAILFAST; mbio->bi_private = r1_bio; @@ -1527,7 +1545,7 @@ static void raid1_write_request(struct mddev *mddev, struct bio *bio, trace_block_bio_remap(mbio, disk_devt(mddev->gendisk), r1_bio->sector); /* flush_pending_writes() needs access to the rdev so...*/ - mbio->bi_bdev = (void *)conf->mirrors[i].rdev; + mbio->bi_bdev = (void *)rdev; cb = blk_check_plugged(raid1_unplug, mddev, sizeof(*plug)); if (cb) |