Some code waits for a metadata update by:
1. flagging that it is needed (MD_CHANGE_DEVS or MD_CHANGE_CLEAN)
2. setting MD_CHANGE_PENDING and waking the management thread
3. waiting for MD_CHANGE_PENDING to be cleared
If the first two are done without locking, the code in md_update_sb()
which checks if it needs to repeat might test if an update is needed
before step 1, then clear MD_CHANGE_PENDING after step 2, resulting
in the wait returning early.
So make sure all places that set MD_CHANGE_PENDING are protected by
mddev->lock.
Reviewed-by: NeilBrown <neilb@xxxxxxxx>
Signed-off-by: Guoqing Jiang <gqjiang@xxxxxxxx>
---
V3 changes:
1. use spin_lock_irqsave/spin_unlock_irqrestore in error funcs and
raid10's __make_request
V2 Changes:
1. s/write_lock/lock which is reported by auto build
drivers/md/md.c | 22 +++++++++++++++++-----
drivers/md/raid1.c | 2 ++
drivers/md/raid10.c | 6 +++++-
drivers/md/raid5-cache.c | 2 ++
drivers/md/raid5.c | 2 ++
5 files changed, 28 insertions(+), 6 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 06f6e81..943c953 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2295,12 +2295,18 @@ repeat:
if (mddev_is_clustered(mddev)) {
if (test_and_clear_bit(MD_CHANGE_DEVS, &mddev->flags))
force_change = 1;
+ if (test_and_clear_bit(MD_CHANGE_CLEAN, &mddev->flags))
+ nospares = 1;
ret = md_cluster_ops->metadata_update_start(mddev);
/* Has someone else has updated the sb */
if (!does_sb_need_changing(mddev)) {
if (ret == 0)
md_cluster_ops->metadata_update_cancel(mddev);
- clear_bit(MD_CHANGE_PENDING, &mddev->flags);
+ spin_lock(&mddev->lock);
+ if (!test_bit(MD_CHANGE_DEVS, &mddev->flags) &&
+ !test_bit(MD_CHANGE_CLEAN, &mddev->flags))
+ clear_bit(MD_CHANGE_PENDING, &mddev->flags);
+ spin_unlock(&mddev->lock);
return;
}
}
@@ -2436,7 +2442,8 @@ repeat:
spin_lock(&mddev->lock);
if (mddev->in_sync != sync_req ||
- test_bit(MD_CHANGE_DEVS, &mddev->flags)) {
+ test_bit(MD_CHANGE_DEVS, &mddev->flags) ||
+ test_bit(MD_CHANGE_CLEAN, &mddev->flags)) {
/* have to write it out again */
spin_unlock(&mddev->lock);
goto repeat;
@@ -8147,18 +8154,20 @@ void md_do_sync(struct md_thread *thread)
}
}
skip:
- set_bit(MD_CHANGE_DEVS, &mddev->flags);
-
if (mddev_is_clustered(mddev) &&
ret == 0) {
/* set CHANGE_PENDING here since maybe another
* update is needed, so other nodes are informed */
+ spin_lock(&mddev->lock);
+ set_bit(MD_CHANGE_DEVS, &mddev->flags);
set_bit(MD_CHANGE_PENDING, &mddev->flags);
+ spin_unlock(&mddev->lock);
md_wakeup_thread(mddev->thread);
wait_event(mddev->sb_wait,
!test_bit(MD_CHANGE_PENDING, &mddev->flags));
md_cluster_ops->resync_finish(mddev);
- }
+ } else
+ set_bit(MD_CHANGE_DEVS, &mddev->flags);
spin_lock(&mddev->lock);
if (!test_bit(MD_RECOVERY_INTR, &mddev->recovery)) {
@@ -8550,6 +8559,7 @@ EXPORT_SYMBOL(md_finish_reshape);
int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
int is_new)
{
+ struct mddev *mddev = rdev->mddev;
int rv;
if (is_new)
s += rdev->new_data_offset;
@@ -8559,8 +8569,10 @@ int rdev_set_badblocks(struct md_rdev *rdev, sector_t s, int sectors,
if (rv == 0) {
/* Make sure they get written out promptly */
sysfs_notify_dirent_safe(rdev->sysfs_state);
+ spin_lock(&mddev->lock);
set_bit(MD_CHANGE_CLEAN, &rdev->mddev->flags);
set_bit(MD_CHANGE_PENDING, &rdev->mddev->flags);
+ spin_unlock(&mddev->lock);
md_wakeup_thread(rdev->mddev->thread);
return 1;
} else
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index a7f2b9c..cffd224 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -1474,8 +1474,10 @@ static void raid1_error(struct mddev *mddev, struct md_rdev *rdev)
* if recovery is running, make sure it aborts.
*/
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
+ spin_lock_irqsave(&mddev->lock, flags);
set_bit(MD_CHANGE_DEVS, &mddev->flags);
set_bit(MD_CHANGE_PENDING, &mddev->flags);
+ spin_unlock_irqrestore(&mddev->lock, flags);
printk(KERN_ALERT
"md/raid1:%s: Disk failure on %s, disabling device.\n"
"md/raid1:%s: Operation continuing on %d devices.\n",
diff --git a/drivers/md/raid10.c b/drivers/md/raid10.c
index e3fd725..cd615fe 100644
--- a/drivers/md/raid10.c
+++ b/drivers/md/raid10.c
@@ -1102,8 +1102,10 @@ static void __make_request(struct mddev *mddev, struct bio *bio)
bio->bi_iter.bi_sector < conf->reshape_progress))) {
/* Need to update reshape_position in metadata */
mddev->reshape_position = conf->reshape_progress;
+ spin_lock_irqsave(&mddev->lock, flags);
set_bit(MD_CHANGE_DEVS, &mddev->flags);
set_bit(MD_CHANGE_PENDING, &mddev->flags);
+ spin_unlock_irqrestore(&mddev->lock, flags);
md_wakeup_thread(mddev->thread);
wait_event(mddev->sb_wait,
!test_bit(MD_CHANGE_PENDING, &mddev->flags));
@@ -1585,15 +1587,17 @@ static void raid10_error(struct mddev *mddev, struct md_rdev *rdev)
}
if (test_and_clear_bit(In_sync, &rdev->flags))
mddev->degraded++;
+ spin_unlock_irqrestore(&conf->device_lock, flags);
/*
* If recovery is running, make sure it aborts.
*/
set_bit(MD_RECOVERY_INTR, &mddev->recovery);
set_bit(Blocked, &rdev->flags);
set_bit(Faulty, &rdev->flags);
+ spin_lock_irqsave(&mddev->lock, flags);
set_bit(MD_CHANGE_DEVS, &mddev->flags);
set_bit(MD_CHANGE_PENDING, &mddev->flags);
- spin_unlock_irqrestore(&conf->device_lock, flags);
+ spin_unlock_irqrestore(&mddev->lock, flags);
printk(KERN_ALERT
"md/raid10:%s: Disk failure on %s, disabling device.\n"
"md/raid10:%s: Operation continuing on %d devices.\n",
diff --git a/drivers/md/raid5-cache.c b/drivers/md/raid5-cache.c
index 9531f5f..2ba9366 100644
--- a/drivers/md/raid5-cache.c
+++ b/drivers/md/raid5-cache.c
@@ -712,8 +712,10 @@ static void r5l_write_super_and_discard_space(struct r5l_log *log,
* in_teardown check workaround this issue.
*/
if (!log->in_teardown) {
+ spin_lock(&mddev->lock);
set_bit(MD_CHANGE_DEVS, &mddev->flags);
set_bit(MD_CHANGE_PENDING, &mddev->flags);
+ spin_unlock(&mddev->lock);
md_wakeup_thread(mddev->thread);
wait_event(mddev->sb_wait,
!test_bit(MD_CHANGE_PENDING, &mddev->flags) ||
diff --git a/drivers/md/raid5.c b/drivers/md/raid5.c
index 8ab8b65..fffa53f 100644
--- a/drivers/md/raid5.c
+++ b/drivers/md/raid5.c
@@ -2514,8 +2514,10 @@ static void raid5_error(struct mddev *mddev, struct md_rdev *rdev)
set_bit(Blocked, &rdev->flags);
set_bit(Faulty, &rdev->flags);
+ spin_lock_irqsave(&mddev->lock, flags);
set_bit(MD_CHANGE_DEVS, &mddev->flags);
set_bit(MD_CHANGE_PENDING, &mddev->flags);
+ spin_unlock_irqrestore(&mddev->lock, flags);
printk(KERN_ALERT
"md/raid:%s: Disk failure on %s, disabling device.\n"
"md/raid:%s: Operation continuing on %d devices.\n",
--
2.6.6
--
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