mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-24 09:50:04 +00:00
md/raid10: add rcu protection to rdev access in raid10_sync_request.
mirrors[].rdev can become NULL at any point unless: - a counted reference is held - ->reconfig_mutex is held, or - rcu_read_lock() is held Previously they could not become NULL during a resync/recovery/reshape either. However when remove_and_add_spares() was added to hot_remove_disk(), that changed. So raid10_sync_request didn't previously need to protect rdev access, but now it does. Fix missed check(Shaohua) Signed-off-by: NeilBrown <neilb@suse.com> Signed-off-by: Shaohua Li <shli@fb.com>
This commit is contained in:
parent
d44b0a928f
commit
f90145f317
1 changed files with 74 additions and 48 deletions
|
@ -2871,11 +2871,14 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
/* Completed a full sync so the replacements
|
||||
* are now fully recovered.
|
||||
*/
|
||||
for (i = 0; i < conf->geo.raid_disks; i++)
|
||||
if (conf->mirrors[i].replacement)
|
||||
conf->mirrors[i].replacement
|
||||
->recovery_offset
|
||||
= MaxSector;
|
||||
rcu_read_lock();
|
||||
for (i = 0; i < conf->geo.raid_disks; i++) {
|
||||
struct md_rdev *rdev =
|
||||
rcu_dereference(conf->mirrors[i].replacement);
|
||||
if (rdev)
|
||||
rdev->recovery_offset = MaxSector;
|
||||
}
|
||||
rcu_read_unlock();
|
||||
}
|
||||
conf->fullsync = 0;
|
||||
}
|
||||
|
@ -2941,14 +2944,19 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
int must_sync;
|
||||
int any_working;
|
||||
struct raid10_info *mirror = &conf->mirrors[i];
|
||||
struct md_rdev *mrdev, *mreplace;
|
||||
|
||||
if ((mirror->rdev == NULL ||
|
||||
test_bit(In_sync, &mirror->rdev->flags))
|
||||
&&
|
||||
(mirror->replacement == NULL ||
|
||||
test_bit(Faulty,
|
||||
&mirror->replacement->flags)))
|
||||
rcu_read_lock();
|
||||
mrdev = rcu_dereference(mirror->rdev);
|
||||
mreplace = rcu_dereference(mirror->replacement);
|
||||
|
||||
if ((mrdev == NULL ||
|
||||
test_bit(In_sync, &mrdev->flags)) &&
|
||||
(mreplace == NULL ||
|
||||
test_bit(Faulty, &mreplace->flags))) {
|
||||
rcu_read_unlock();
|
||||
continue;
|
||||
}
|
||||
|
||||
still_degraded = 0;
|
||||
/* want to reconstruct this device */
|
||||
|
@ -2958,6 +2966,7 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
/* last stripe is not complete - don't
|
||||
* try to recover this sector.
|
||||
*/
|
||||
rcu_read_unlock();
|
||||
continue;
|
||||
}
|
||||
/* Unless we are doing a full sync, or a replacement
|
||||
|
@ -2969,14 +2978,19 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
if (sync_blocks < max_sync)
|
||||
max_sync = sync_blocks;
|
||||
if (!must_sync &&
|
||||
mirror->replacement == NULL &&
|
||||
mreplace == NULL &&
|
||||
!conf->fullsync) {
|
||||
/* yep, skip the sync_blocks here, but don't assume
|
||||
* that there will never be anything to do here
|
||||
*/
|
||||
chunks_skipped = -1;
|
||||
rcu_read_unlock();
|
||||
continue;
|
||||
}
|
||||
atomic_inc(&mrdev->nr_pending);
|
||||
if (mreplace)
|
||||
atomic_inc(&mreplace->nr_pending);
|
||||
rcu_read_unlock();
|
||||
|
||||
r10_bio = mempool_alloc(conf->r10buf_pool, GFP_NOIO);
|
||||
r10_bio->state = 0;
|
||||
|
@ -2995,12 +3009,15 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
/* Need to check if the array will still be
|
||||
* degraded
|
||||
*/
|
||||
for (j = 0; j < conf->geo.raid_disks; j++)
|
||||
if (conf->mirrors[j].rdev == NULL ||
|
||||
test_bit(Faulty, &conf->mirrors[j].rdev->flags)) {
|
||||
rcu_read_lock();
|
||||
for (j = 0; j < conf->geo.raid_disks; j++) {
|
||||
struct md_rdev *rdev = rcu_dereference(
|
||||
conf->mirrors[j].rdev);
|
||||
if (rdev == NULL || test_bit(Faulty, &rdev->flags)) {
|
||||
still_degraded = 1;
|
||||
break;
|
||||
}
|
||||
}
|
||||
|
||||
must_sync = bitmap_start_sync(mddev->bitmap, sect,
|
||||
&sync_blocks, still_degraded);
|
||||
|
@ -3010,15 +3027,15 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
int k;
|
||||
int d = r10_bio->devs[j].devnum;
|
||||
sector_t from_addr, to_addr;
|
||||
struct md_rdev *rdev;
|
||||
struct md_rdev *rdev =
|
||||
rcu_dereference(conf->mirrors[d].rdev);
|
||||
sector_t sector, first_bad;
|
||||
int bad_sectors;
|
||||
if (!conf->mirrors[d].rdev ||
|
||||
!test_bit(In_sync, &conf->mirrors[d].rdev->flags))
|
||||
if (!rdev ||
|
||||
!test_bit(In_sync, &rdev->flags))
|
||||
continue;
|
||||
/* This is where we read from */
|
||||
any_working = 1;
|
||||
rdev = conf->mirrors[d].rdev;
|
||||
sector = r10_bio->devs[j].addr;
|
||||
|
||||
if (is_badblock(rdev, sector, max_sync,
|
||||
|
@ -3057,8 +3074,7 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
r10_bio->devs[1].devnum = i;
|
||||
r10_bio->devs[1].addr = to_addr;
|
||||
|
||||
rdev = mirror->rdev;
|
||||
if (!test_bit(In_sync, &rdev->flags)) {
|
||||
if (!test_bit(In_sync, &mrdev->flags)) {
|
||||
bio = r10_bio->devs[1].bio;
|
||||
bio_reset(bio);
|
||||
bio->bi_next = biolist;
|
||||
|
@ -3067,8 +3083,8 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
bio->bi_end_io = end_sync_write;
|
||||
bio->bi_rw = WRITE;
|
||||
bio->bi_iter.bi_sector = to_addr
|
||||
+ rdev->data_offset;
|
||||
bio->bi_bdev = rdev->bdev;
|
||||
+ mrdev->data_offset;
|
||||
bio->bi_bdev = mrdev->bdev;
|
||||
atomic_inc(&r10_bio->remaining);
|
||||
} else
|
||||
r10_bio->devs[1].bio->bi_end_io = NULL;
|
||||
|
@ -3077,8 +3093,7 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
bio = r10_bio->devs[1].repl_bio;
|
||||
if (bio)
|
||||
bio->bi_end_io = NULL;
|
||||
rdev = mirror->replacement;
|
||||
/* Note: if rdev != NULL, then bio
|
||||
/* Note: if mreplace != NULL, then bio
|
||||
* cannot be NULL as r10buf_pool_alloc will
|
||||
* have allocated it.
|
||||
* So the second test here is pointless.
|
||||
|
@ -3086,8 +3101,8 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
* this comment keeps human reviewers
|
||||
* happy.
|
||||
*/
|
||||
if (rdev == NULL || bio == NULL ||
|
||||
test_bit(Faulty, &rdev->flags))
|
||||
if (mreplace == NULL || bio == NULL ||
|
||||
test_bit(Faulty, &mreplace->flags))
|
||||
break;
|
||||
bio_reset(bio);
|
||||
bio->bi_next = biolist;
|
||||
|
@ -3096,11 +3111,12 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
bio->bi_end_io = end_sync_write;
|
||||
bio->bi_rw = WRITE;
|
||||
bio->bi_iter.bi_sector = to_addr +
|
||||
rdev->data_offset;
|
||||
bio->bi_bdev = rdev->bdev;
|
||||
mreplace->data_offset;
|
||||
bio->bi_bdev = mreplace->bdev;
|
||||
atomic_inc(&r10_bio->remaining);
|
||||
break;
|
||||
}
|
||||
rcu_read_unlock();
|
||||
if (j == conf->copies) {
|
||||
/* Cannot recover, so abort the recovery or
|
||||
* record a bad block */
|
||||
|
@ -3113,15 +3129,15 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
if (r10_bio->devs[k].devnum == i)
|
||||
break;
|
||||
if (!test_bit(In_sync,
|
||||
&mirror->rdev->flags)
|
||||
&mrdev->flags)
|
||||
&& !rdev_set_badblocks(
|
||||
mirror->rdev,
|
||||
mrdev,
|
||||
r10_bio->devs[k].addr,
|
||||
max_sync, 0))
|
||||
any_working = 0;
|
||||
if (mirror->replacement &&
|
||||
if (mreplace &&
|
||||
!rdev_set_badblocks(
|
||||
mirror->replacement,
|
||||
mreplace,
|
||||
r10_bio->devs[k].addr,
|
||||
max_sync, 0))
|
||||
any_working = 0;
|
||||
|
@ -3139,8 +3155,14 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
if (rb2)
|
||||
atomic_dec(&rb2->remaining);
|
||||
r10_bio = rb2;
|
||||
rdev_dec_pending(mrdev, mddev);
|
||||
if (mreplace)
|
||||
rdev_dec_pending(mreplace, mddev);
|
||||
break;
|
||||
}
|
||||
rdev_dec_pending(mrdev, mddev);
|
||||
if (mreplace)
|
||||
rdev_dec_pending(mreplace, mddev);
|
||||
}
|
||||
if (biolist == NULL) {
|
||||
while (r10_bio) {
|
||||
|
@ -3185,6 +3207,7 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
int d = r10_bio->devs[i].devnum;
|
||||
sector_t first_bad, sector;
|
||||
int bad_sectors;
|
||||
struct md_rdev *rdev;
|
||||
|
||||
if (r10_bio->devs[i].repl_bio)
|
||||
r10_bio->devs[i].repl_bio->bi_end_io = NULL;
|
||||
|
@ -3192,12 +3215,14 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
bio = r10_bio->devs[i].bio;
|
||||
bio_reset(bio);
|
||||
bio->bi_error = -EIO;
|
||||
if (conf->mirrors[d].rdev == NULL ||
|
||||
test_bit(Faulty, &conf->mirrors[d].rdev->flags))
|
||||
rcu_read_lock();
|
||||
rdev = rcu_dereference(conf->mirrors[d].rdev);
|
||||
if (rdev == NULL || test_bit(Faulty, &rdev->flags)) {
|
||||
rcu_read_unlock();
|
||||
continue;
|
||||
}
|
||||
sector = r10_bio->devs[i].addr;
|
||||
if (is_badblock(conf->mirrors[d].rdev,
|
||||
sector, max_sync,
|
||||
if (is_badblock(rdev, sector, max_sync,
|
||||
&first_bad, &bad_sectors)) {
|
||||
if (first_bad > sector)
|
||||
max_sync = first_bad - sector;
|
||||
|
@ -3205,25 +3230,28 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
bad_sectors -= (sector - first_bad);
|
||||
if (max_sync > bad_sectors)
|
||||
max_sync = bad_sectors;
|
||||
rcu_read_unlock();
|
||||
continue;
|
||||
}
|
||||
}
|
||||
atomic_inc(&conf->mirrors[d].rdev->nr_pending);
|
||||
atomic_inc(&rdev->nr_pending);
|
||||
atomic_inc(&r10_bio->remaining);
|
||||
bio->bi_next = biolist;
|
||||
biolist = bio;
|
||||
bio->bi_private = r10_bio;
|
||||
bio->bi_end_io = end_sync_read;
|
||||
bio->bi_rw = READ;
|
||||
bio->bi_iter.bi_sector = sector +
|
||||
conf->mirrors[d].rdev->data_offset;
|
||||
bio->bi_bdev = conf->mirrors[d].rdev->bdev;
|
||||
bio->bi_iter.bi_sector = sector + rdev->data_offset;
|
||||
bio->bi_bdev = rdev->bdev;
|
||||
count++;
|
||||
|
||||
if (conf->mirrors[d].replacement == NULL ||
|
||||
test_bit(Faulty,
|
||||
&conf->mirrors[d].replacement->flags))
|
||||
rdev = rcu_dereference(conf->mirrors[d].replacement);
|
||||
if (rdev == NULL || test_bit(Faulty, &rdev->flags)) {
|
||||
rcu_read_unlock();
|
||||
continue;
|
||||
}
|
||||
atomic_inc(&rdev->nr_pending);
|
||||
rcu_read_unlock();
|
||||
|
||||
/* Need to set up for writing to the replacement */
|
||||
bio = r10_bio->devs[i].repl_bio;
|
||||
|
@ -3231,15 +3259,13 @@ static sector_t raid10_sync_request(struct mddev *mddev, sector_t sector_nr,
|
|||
bio->bi_error = -EIO;
|
||||
|
||||
sector = r10_bio->devs[i].addr;
|
||||
atomic_inc(&conf->mirrors[d].replacement->nr_pending);
|
||||
bio->bi_next = biolist;
|
||||
biolist = bio;
|
||||
bio->bi_private = r10_bio;
|
||||
bio->bi_end_io = end_sync_write;
|
||||
bio->bi_rw = WRITE;
|
||||
bio->bi_iter.bi_sector = sector +
|
||||
conf->mirrors[d].replacement->data_offset;
|
||||
bio->bi_bdev = conf->mirrors[d].replacement->bdev;
|
||||
bio->bi_iter.bi_sector = sector + rdev->data_offset;
|
||||
bio->bi_bdev = rdev->bdev;
|
||||
count++;
|
||||
}
|
||||
|
||||
|
|
Loading…
Reference in a new issue