From: Bob Peterson rpeterso@redhat.com
[ Upstream commit d1340f80f0b8066321b499a376780da00560e857 ]
In the gfs2 withdraw sequence, the dlm protocol is unmounted with a call to lm_unmount. After a withdraw, users are allowed to unmount the withdrawn file system. But at that point we may still have glocks left over that we need to free via unmount's call to gfs2_gl_hash_clear. These glocks may have never been completed because of whatever problem caused the withdraw (IO errors or whatever).
Before this patch, function gdlm_put_lock would still try to call into dlm to unlock these leftover glocks, which resulted in dlm returning -EINVAL because the lock space was abandoned. These glocks were never freed because there was no mechanism after that to free them.
This patch adds a check to gdlm_put_lock to see if the locking protocol was inactive (DFL_UNMOUNT flag) and if so, free the glock and not make the invalid call into dlm.
I could have combined this "if" with the one that follows, related to leftover glock LVBs, but I felt the code was more readable with its own if clause.
Signed-off-by: Bob Peterson rpeterso@redhat.com Signed-off-by: Sasha Levin sashal@kernel.org --- fs/gfs2/lock_dlm.c | 5 +++++ 1 file changed, 5 insertions(+)
diff --git a/fs/gfs2/lock_dlm.c b/fs/gfs2/lock_dlm.c index de733a6c30bb..f3c16a504c8d 100644 --- a/fs/gfs2/lock_dlm.c +++ b/fs/gfs2/lock_dlm.c @@ -295,6 +295,11 @@ static void gdlm_put_lock(struct gfs2_glock *gl) gfs2_sbstats_inc(gl, GFS2_LKS_DCOUNT); gfs2_update_request_times(gl);
+ /* don't want to call dlm if we've unmounted the lock protocol */ + if (test_bit(DFL_UNMOUNT, &ls->ls_recover_flags)) { + gfs2_glock_free(gl); + return; + } /* don't want to skip dlm_unlock writing the lvb when lock has one */
if (test_bit(SDF_SKIP_DLM_UNLOCK, &sdp->sd_flags) &&