From 86934198eefa10a71f35162b06c44c36d85b98ba Mon Sep 17 00:00:00 2001 From: Bob Peterson Date: Thu, 18 Aug 2022 13:32:38 -0500 Subject: [PATCH] gfs2: Clear flags when withdraw prevents xmote There are a couple places in function do_xmote where normal processing is circumvented due to withdraws in progress. However, since we bypass most of do_xmote() we bypass telling dlm to lock the dlm lock, which means dlm will never respond with a completion callback. Since the completion callback ordinarily clears GLF_LOCK, this patch changes function do_xmote to handle those situations more gracefully so the file system may be unmounted after withdraw. A very similar situation happens with the GLF_DEMOTE_IN_PROGRESS flag, which is cleared by function finish_xmote(). Since the withdraw causes us to skip the majority of do_xmote, it therefore also skips the call to finish_xmote() so the DEMOTE_IN_PROGRESS flag needs to be cleared manually. Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher --- fs/gfs2/glock.c | 22 ++++++++++++++++++++-- 1 file changed, 20 insertions(+), 2 deletions(-) diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index 858616afcae6..dca2cbf0338c 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -59,6 +59,8 @@ typedef void (*glock_examiner) (struct gfs2_glock * gl); static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target); static void __gfs2_glock_dq(struct gfs2_holder *gh); +static void handle_callback(struct gfs2_glock *gl, unsigned int state, + unsigned long delay, bool remote); static struct dentry *gfs2_root; static struct workqueue_struct *glock_workqueue; @@ -730,7 +732,8 @@ static bool is_system_glock(struct gfs2_glock *gl) * */ -static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, unsigned int target) +static void do_xmote(struct gfs2_glock *gl, struct gfs2_holder *gh, + unsigned int target) __releases(&gl->gl_lockref.lock) __acquires(&gl->gl_lockref.lock) { @@ -741,7 +744,8 @@ __acquires(&gl->gl_lockref.lock) if (target != LM_ST_UNLOCKED && glock_blocked_by_withdraw(gl) && gh && !(gh->gh_flags & LM_FLAG_NOEXP)) - return; + goto skip_inval; + lck_flags &= (LM_FLAG_TRY | LM_FLAG_TRY_1CB | LM_FLAG_NOEXP | LM_FLAG_PRIORITY); GLOCK_BUG_ON(gl, gl->gl_state == target); @@ -826,6 +830,20 @@ skip_inval: (target != LM_ST_UNLOCKED || test_bit(SDF_WITHDRAW_RECOVERY, &sdp->sd_flags))) { if (!is_system_glock(gl)) { + handle_callback(gl, LM_ST_UNLOCKED, 0, false); /* sets demote */ + /* + * Ordinarily, we would call dlm and its callback would call + * finish_xmote, which would call state_change() to the new state. + * Since we withdrew, we won't call dlm, so call state_change + * manually, but to the UNLOCKED state we desire. + */ + state_change(gl, LM_ST_UNLOCKED); + /* + * We skip telling dlm to do the locking, so we won't get a + * reply that would otherwise clear GLF_LOCK. So we clear it here. + */ + clear_bit(GLF_LOCK, &gl->gl_flags); + clear_bit(GLF_DEMOTE_IN_PROGRESS, &gl->gl_flags); gfs2_glock_queue_work(gl, GL_GLOCK_DFT_HOLD); goto out; } else {