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authorSong Liu <songliubraving@fb.com>2020-12-09 22:43:08 +0300
committerSong Liu <songliubraving@fb.com>2020-12-10 07:46:00 +0300
commitd7cb6be0d0cdced2a7a96bd80a8f835e77ec5204 (patch)
tree7270755c2e92c266f0a0f1d7f9757c9ce789db81 /drivers/md
parent82fe9af77cd11ea7bdc133ceed1f7f5fc08f7d25 (diff)
downloadlinux-d7cb6be0d0cdced2a7a96bd80a8f835e77ec5204.tar.xz
Revert "md/raid10: improve raid10 discard request"
This reverts commit bcc90d280465ebd51ab8688be86e1f00c62dccf9. Matthew Ruffell reported data corruption in raid10 due to the changes in discard handling [1]. Revert these changes before we find a proper fix. [1] https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1907262/ Cc: Matthew Ruffell <matthew.ruffell@canonical.com> Cc: Xiao Ni <xni@redhat.com> Signed-off-by: Song Liu <songliubraving@fb.com>
Diffstat (limited to 'drivers/md')
-rw-r--r--drivers/md/raid10.c256
1 files changed, 1 insertions, 255 deletions
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index 05773ee1b5ba..4ad8447fa868 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1516,256 +1516,6 @@ static void __make_request(struct mddev *mddev, struct bio *bio, int sectors)
raid10_write_request(mddev, bio, r10_bio);
}
-static struct bio *raid10_split_bio(struct r10conf *conf,
- struct bio *bio, sector_t sectors, bool want_first)
-{
- struct bio *split;
-
- split = bio_split(bio, sectors, GFP_NOIO, &conf->bio_split);
- bio_chain(split, bio);
- allow_barrier(conf);
- if (want_first) {
- submit_bio_noacct(bio);
- bio = split;
- } else
- submit_bio_noacct(split);
- wait_barrier(conf);
-
- return bio;
-}
-
-static void raid10_end_discard_request(struct bio *bio)
-{
- struct r10bio *r10_bio = bio->bi_private;
- struct r10conf *conf = r10_bio->mddev->private;
- struct md_rdev *rdev = NULL;
- int dev;
- int slot, repl;
-
- /*
- * We don't care the return value of discard bio
- */
- if (!test_bit(R10BIO_Uptodate, &r10_bio->state))
- set_bit(R10BIO_Uptodate, &r10_bio->state);
-
- dev = find_bio_disk(conf, r10_bio, bio, &slot, &repl);
- if (repl)
- rdev = conf->mirrors[dev].replacement;
- if (!rdev) {
- /* raid10_remove_disk uses smp_mb to make sure rdev is set to
- * replacement before setting replacement to NULL. It can read
- * rdev first without barrier protect even replacment is NULL
- */
- smp_rmb();
- rdev = conf->mirrors[dev].rdev;
- }
-
- if (atomic_dec_and_test(&r10_bio->remaining)) {
- md_write_end(r10_bio->mddev);
- raid_end_bio_io(r10_bio);
- }
-
- rdev_dec_pending(rdev, conf->mddev);
-}
-
-/* There are some limitations to handle discard bio
- * 1st, the discard size is bigger than stripe_size*2.
- * 2st, if the discard bio spans reshape progress, we use the old way to
- * handle discard bio
- */
-static int raid10_handle_discard(struct mddev *mddev, struct bio *bio)
-{
- struct r10conf *conf = mddev->private;
- struct geom *geo = &conf->geo;
- struct r10bio *r10_bio;
-
- int disk;
- sector_t chunk;
- unsigned int stripe_size;
- sector_t split_size;
-
- sector_t bio_start, bio_end;
- sector_t first_stripe_index, last_stripe_index;
- sector_t start_disk_offset;
- unsigned int start_disk_index;
- sector_t end_disk_offset;
- unsigned int end_disk_index;
- unsigned int remainder;
-
- if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
- return -EAGAIN;
-
- wait_barrier(conf);
-
- /* Check reshape again to avoid reshape happens after checking
- * MD_RECOVERY_RESHAPE and before wait_barrier
- */
- if (test_bit(MD_RECOVERY_RESHAPE, &mddev->recovery))
- goto out;
-
- stripe_size = geo->raid_disks << geo->chunk_shift;
- bio_start = bio->bi_iter.bi_sector;
- bio_end = bio_end_sector(bio);
-
- /* Maybe one discard bio is smaller than strip size or across one stripe
- * and discard region is larger than one stripe size. For far offset layout,
- * if the discard region is not aligned with stripe size, there is hole
- * when we submit discard bio to member disk. For simplicity, we only
- * handle discard bio which discard region is bigger than stripe_size*2
- */
- if (bio_sectors(bio) < stripe_size*2)
- goto out;
-
- /* For far offset layout, if bio is not aligned with stripe size, it splits
- * the part that is not aligned with strip size.
- */
- div_u64_rem(bio_start, stripe_size, &remainder);
- if (geo->far_offset && remainder) {
- split_size = stripe_size - remainder;
- bio = raid10_split_bio(conf, bio, split_size, false);
- }
- div_u64_rem(bio_end, stripe_size, &remainder);
- if (geo->far_offset && remainder) {
- split_size = bio_sectors(bio) - remainder;
- bio = raid10_split_bio(conf, bio, split_size, true);
- }
-
- r10_bio = mempool_alloc(&conf->r10bio_pool, GFP_NOIO);
- r10_bio->mddev = mddev;
- r10_bio->state = 0;
- r10_bio->sectors = 0;
- memset(r10_bio->devs, 0, sizeof(r10_bio->devs[0]) * geo->raid_disks);
-
- wait_blocked_dev(mddev, r10_bio);
-
- r10_bio->master_bio = bio;
-
- bio_start = bio->bi_iter.bi_sector;
- bio_end = bio_end_sector(bio);
-
- /* raid10 uses chunk as the unit to store data. It's similar like raid0.
- * One stripe contains the chunks from all member disk (one chunk from
- * one disk at the same HBA address). For layout detail, see 'man md 4'
- */
- chunk = bio_start >> geo->chunk_shift;
- chunk *= geo->near_copies;
- first_stripe_index = chunk;
- start_disk_index = sector_div(first_stripe_index, geo->raid_disks);
- if (geo->far_offset)
- first_stripe_index *= geo->far_copies;
- start_disk_offset = (bio_start & geo->chunk_mask) +
- (first_stripe_index << geo->chunk_shift);
-
- chunk = bio_end >> geo->chunk_shift;
- chunk *= geo->near_copies;
- last_stripe_index = chunk;
- end_disk_index = sector_div(last_stripe_index, geo->raid_disks);
- if (geo->far_offset)
- last_stripe_index *= geo->far_copies;
- end_disk_offset = (bio_end & geo->chunk_mask) +
- (last_stripe_index << geo->chunk_shift);
-
- rcu_read_lock();
- for (disk = 0; disk < geo->raid_disks; disk++) {
- struct md_rdev *rdev = rcu_dereference(conf->mirrors[disk].rdev);
- struct md_rdev *rrdev = rcu_dereference(
- conf->mirrors[disk].replacement);
-
- r10_bio->devs[disk].bio = NULL;
- r10_bio->devs[disk].repl_bio = NULL;
-
- if (rdev && (test_bit(Faulty, &rdev->flags)))
- rdev = NULL;
- if (rrdev && (test_bit(Faulty, &rrdev->flags)))
- rrdev = NULL;
- if (!rdev && !rrdev)
- continue;
-
- if (rdev) {
- r10_bio->devs[disk].bio = bio;
- atomic_inc(&rdev->nr_pending);
- }
- if (rrdev) {
- r10_bio->devs[disk].repl_bio = bio;
- atomic_inc(&rrdev->nr_pending);
- }
- }
- rcu_read_unlock();
-
- atomic_set(&r10_bio->remaining, 1);
- for (disk = 0; disk < geo->raid_disks; disk++) {
- sector_t dev_start, dev_end;
- struct bio *mbio, *rbio = NULL;
- struct md_rdev *rdev = rcu_dereference(conf->mirrors[disk].rdev);
- struct md_rdev *rrdev = rcu_dereference(
- conf->mirrors[disk].replacement);
-
- /*
- * Now start to calculate the start and end address for each disk.
- * The space between dev_start and dev_end is the discard region.
- *
- * For dev_start, it needs to consider three conditions:
- * 1st, the disk is before start_disk, you can imagine the disk in
- * the next stripe. So the dev_start is the start address of next
- * stripe.
- * 2st, the disk is after start_disk, it means the disk is at the
- * same stripe of first disk
- * 3st, the first disk itself, we can use start_disk_offset directly
- */
- if (disk < start_disk_index)
- dev_start = (first_stripe_index + 1) * mddev->chunk_sectors;
- else if (disk > start_disk_index)
- dev_start = first_stripe_index * mddev->chunk_sectors;
- else
- dev_start = start_disk_offset;
-
- if (disk < end_disk_index)
- dev_end = (last_stripe_index + 1) * mddev->chunk_sectors;
- else if (disk > end_disk_index)
- dev_end = last_stripe_index * mddev->chunk_sectors;
- else
- dev_end = end_disk_offset;
-
- /* It only handles discard bio which size is >= stripe size, so
- * dev_end > dev_start all the time
- */
- if (r10_bio->devs[disk].bio) {
- mbio = bio_clone_fast(bio, GFP_NOIO, &mddev->bio_set);
- mbio->bi_end_io = raid10_end_discard_request;
- mbio->bi_private = r10_bio;
- r10_bio->devs[disk].bio = mbio;
- r10_bio->devs[disk].devnum = disk;
- atomic_inc(&r10_bio->remaining);
- md_submit_discard_bio(mddev, rdev, mbio,
- dev_start + choose_data_offset(r10_bio, rdev),
- dev_end - dev_start);
- bio_endio(mbio);
- }
- if (r10_bio->devs[disk].repl_bio) {
- rbio = bio_clone_fast(bio, GFP_NOIO, &mddev->bio_set);
- rbio->bi_end_io = raid10_end_discard_request;
- rbio->bi_private = r10_bio;
- r10_bio->devs[disk].repl_bio = rbio;
- r10_bio->devs[disk].devnum = disk;
- atomic_inc(&r10_bio->remaining);
- md_submit_discard_bio(mddev, rrdev, rbio,
- dev_start + choose_data_offset(r10_bio, rrdev),
- dev_end - dev_start);
- bio_endio(rbio);
- }
- }
-
- if (atomic_dec_and_test(&r10_bio->remaining)) {
- md_write_end(r10_bio->mddev);
- raid_end_bio_io(r10_bio);
- }
-
- return 0;
-out:
- allow_barrier(conf);
- return -EAGAIN;
-}
-
static bool raid10_make_request(struct mddev *mddev, struct bio *bio)
{
struct r10conf *conf = mddev->private;
@@ -1780,10 +1530,6 @@ static bool raid10_make_request(struct mddev *mddev, struct bio *bio)
if (!md_write_start(mddev, bio))
return false;
- if (unlikely(bio_op(bio) == REQ_OP_DISCARD))
- if (!raid10_handle_discard(mddev, bio))
- return true;
-
/*
* If this request crosses a chunk boundary, we need to split
* it.
@@ -4023,7 +3769,7 @@ static int raid10_run(struct mddev *mddev)
if (mddev->queue) {
blk_queue_max_discard_sectors(mddev->queue,
- UINT_MAX);
+ mddev->chunk_sectors);
blk_queue_max_write_same_sectors(mddev->queue, 0);
blk_queue_max_write_zeroes_sectors(mddev->queue, 0);
blk_queue_io_min(mddev->queue, mddev->chunk_sectors << 9);