From: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
To incorporate --grow feature executed on one node, other nodes need to
acknowledge the change in number of disks. Call update_raid_disks()
to update internal data structures.
This leads to call check_reshape() -> md_allow_write() -> md_update_sb(),
this results in a deadlock. This is done so it can safely allocate memory
(which might trigger writeback which might write to raid1). This is
not required for md with a bitmap.
In the clustered case, we don't perform md_update_sb() in md_allow_write(),
but in do_md_run(). Also we disable safemode for clustered mode.
mddev->recovery_cp need not be set in check_sb_changes() because this
is required only when a node reads another node's bitmap. mddev->recovery_cp
(which is read from sb->resync_offset), is set only if mddev is in_sync.
Since we disabled safemode, in_sync is set to zero.
In a clustered environment, the MD may not be in sync because another
node could be writing to it. So make sure that in_sync is not set in
case of clustered node in __md_stop_writes().
Signed-off-by: Goldwyn Rodrigues <rgoldwyn@xxxxxxxx>
---
drivers/md/md.c | 22 ++++++++++++++++------
drivers/md/raid1.c | 8 +++++---
2 files changed, 21 insertions(+), 9 deletions(-)
diff --git a/drivers/md/md.c b/drivers/md/md.c
index a71b36f..0c70856 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -2230,7 +2230,6 @@ static bool does_sb_need_changing(struct mddev *mddev)
/* Check if any mddev parameters have changed */
if ((mddev->dev_sectors != le64_to_cpu(sb->size)) ||
(mddev->reshape_position != le64_to_cpu(sb->reshape_position)) ||
- (mddev->recovery_cp != le64_to_cpu(sb->resync_offset)) ||
(mddev->layout != le64_to_cpu(sb->layout)) ||
(mddev->raid_disks != le32_to_cpu(sb->raid_disks)) ||
(mddev->chunk_sectors != le32_to_cpu(sb->chunksize)))
@@ -3314,6 +3313,11 @@ safe_delay_store(struct mddev *mddev, const char *cbuf, size_t len)
{
unsigned long msec;
+ if (mddev_is_clustered(mddev)) {
+ pr_info("md: Safemode is disabled for clustered mode\n");
+ return -EINVAL;
+ }
+
if (strict_strtoul_scaled(cbuf, &msec, 3) < 0)
return -EINVAL;
if (msec == 0)
@@ -5224,7 +5228,10 @@ int md_run(struct mddev *mddev)
atomic_set(&mddev->max_corr_read_errors,
MD_DEFAULT_MAX_CORRECTED_READ_ERRORS);
mddev->safemode = 0;
- mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
+ if (mddev_is_clustered(mddev))
+ mddev->safemode_delay = 0;
+ else
+ mddev->safemode_delay = (200 * HZ)/1000 +1; /* 200 msec delay */
mddev->in_sync = 1;
smp_wmb();
spin_lock(&mddev->lock);
@@ -5267,6 +5274,9 @@ static int do_md_run(struct mddev *mddev)
goto out;
}
+ if (mddev_is_clustered(mddev))
+ md_allow_write(mddev);
+
md_wakeup_thread(mddev->thread);
md_wakeup_thread(mddev->sync_thread); /* possibly kick off a reshape */
@@ -5363,7 +5373,8 @@ static void __md_stop_writes(struct mddev *mddev)
md_super_wait(mddev);
if (mddev->ro == 0 &&
- (!mddev->in_sync || (mddev->flags & MD_UPDATE_SB_FLAGS))) {
+ ((!mddev->in_sync && !mddev_is_clustered(mddev)) ||
+ (mddev->flags & MD_UPDATE_SB_FLAGS))) {
/* mark array as shutdown cleanly */
mddev->in_sync = 1;
md_update_sb(mddev, 1);
@@ -9007,9 +9018,8 @@ static void check_sb_changes(struct mddev *mddev, struct md_rdev *rdev)
}
}
- /* recovery_cp changed */
- if (le64_to_cpu(sb->resync_offset) != mddev->recovery_cp)
- mddev->recovery_cp = le64_to_cpu(sb->resync_offset);
+ if (mddev->raid_disks != le32_to_cpu(sb->raid_disks))
+ update_raid_disks(mddev, le32_to_cpu(sb->raid_disks));
/* Finally set the event to be up to date */
mddev->events = le64_to_cpu(sb->events);
diff --git a/drivers/md/raid1.c b/drivers/md/raid1.c
index a2d813c..5f38430 100644
--- a/drivers/md/raid1.c
+++ b/drivers/md/raid1.c
@@ -3044,9 +3044,11 @@ static int raid1_reshape(struct mddev *mddev)
return -EINVAL;
}
- err = md_allow_write(mddev);
- if (err)
- return err;
+ if (!mddev_is_clustered(mddev)) {
+ err = md_allow_write(mddev);
+ if (err)
+ return err;
+ }
raid_disks = mddev->raid_disks + mddev->delta_disks;
--
1.8.5.6
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