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| author | Lars Ellenberg <lars.ellenberg@linbit.com> | 2012-04-25 18:27:35 +0400 |
|---|---|---|
| committer | Philipp Reisner <philipp.reisner@linbit.com> | 2012-05-09 17:16:59 +0400 |
| commit | a574daf5d722f4ca8cc18509f30b804c4d519962 (patch) | |
| tree | 83ae95ce9a57d605ce2a308ceb2a026e9f2ca9b2 /drivers/block | |
| parent | ba280c092e6eca8a70c502e4510061535fdce382 (diff) | |
| download | linux-a574daf5d722f4ca8cc18509f30b804c4d519962.tar.xz | |
drbd: fix race between drbdadm invalidate/verify and finishing resync
When a resync or online verify is finished or aborted,
drbd does a bulk write-out of changed bitmap pages.
If *in that very moment* a new verify or resync is triggered,
this can race:
ASSERT( !test_bit(BITMAP_IO, &mdev->flags) ) in drbd_main.c
FIXME going to queue 'set_n_write from StartingSync' but 'write from resync_finished' still pending?
and similar.
This can be observed with e.g. tight invalidate loops in test scripts,
and probably has no real-life implication.
Still, that race can be solved by first quiescen the device,
before starting a new resync or verify.
Signed-off-by: Philipp Reisner <philipp.reisner@linbit.com>
Signed-off-by: Lars Ellenberg <lars.ellenberg@linbit.com>
Diffstat (limited to 'drivers/block')
| -rw-r--r-- | drivers/block/drbd/drbd_nl.c | 6 |
1 files changed, 6 insertions, 0 deletions
diff --git a/drivers/block/drbd/drbd_nl.c b/drivers/block/drbd/drbd_nl.c index 308beb8c0c1e..867bf1d82988 100644 --- a/drivers/block/drbd/drbd_nl.c +++ b/drivers/block/drbd/drbd_nl.c @@ -1963,6 +1963,7 @@ static int drbd_nl_invalidate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nl /* If there is still bitmap IO pending, probably because of a previous * resync just being finished, wait for it before requesting a new resync. */ + drbd_suspend_io(mdev); wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags)); retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T), CS_ORDERED); @@ -1981,6 +1982,7 @@ static int drbd_nl_invalidate(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nl retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_T)); } + drbd_resume_io(mdev); reply->ret_code = retcode; return 0; @@ -2002,6 +2004,7 @@ static int drbd_nl_invalidate_peer(struct drbd_conf *mdev, struct drbd_nl_cfg_re /* If there is still bitmap IO pending, probably because of a previous * resync just being finished, wait for it before requesting a new resync. */ + drbd_suspend_io(mdev); wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags)); retcode = _drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S), CS_ORDERED); @@ -2020,6 +2023,7 @@ static int drbd_nl_invalidate_peer(struct drbd_conf *mdev, struct drbd_nl_cfg_re } else retcode = drbd_request_state(mdev, NS(conn, C_STARTING_SYNC_S)); } + drbd_resume_io(mdev); reply->ret_code = retcode; return 0; @@ -2192,11 +2196,13 @@ static int drbd_nl_start_ov(struct drbd_conf *mdev, struct drbd_nl_cfg_req *nlp, /* If there is still bitmap IO pending, e.g. previous resync or verify * just being finished, wait for it before requesting a new resync. */ + drbd_suspend_io(mdev); wait_event(mdev->misc_wait, !test_bit(BITMAP_IO, &mdev->flags)); /* w_make_ov_request expects position to be aligned */ mdev->ov_start_sector = args.start_sector & ~BM_SECT_PER_BIT; reply->ret_code = drbd_request_state(mdev,NS(conn,C_VERIFY_S)); + drbd_resume_io(mdev); return 0; } |