From: Fan Yong <fan.yong@intel.com>
Date: Wed, 13 Dec 2017 05:35:39 +0000 (+0800)
Subject: LU-10321 lfsck: not start lfsck during umount
X-Git-Url: https://git.whamcloud.com/?a=commitdiff_plain;h=refs%2Fchanges%2F13%2F30513%2F1;p=fs%2Flustre-release.git

LU-10321 lfsck: not start lfsck during umount

There is race condition bewtween lfsck_start and umount:
the LFSCK may be triggered just after the LFSCK stopped
during umount the target, then nobody will stop the new
started LFSCK, as to the umount may be blocked.

This patch sets flag on the lfsck instance when umount
that will prevent subsequent lfsck_start.

Signed-off-by: Fan Yong <fan.yong@intel.com>
Change-Id: I779f862d4195d4289bb9dd96575cd7746ac4b35b
---

diff --git a/lustre/lfsck/lfsck_internal.h b/lustre/lfsck/lfsck_internal.h
index a9df386..5f2bcba 100644
--- a/lustre/lfsck/lfsck_internal.h
+++ b/lustre/lfsck/lfsck_internal.h
@@ -744,7 +744,8 @@ struct lfsck_instance {
 				  li_drop_dryrun:1, /* Ever dryrun, not now. */
 				  li_master:1, /* Master instance or not. */
 				  li_current_oit_processed:1,
-				  li_start_unplug:1;
+				  li_start_unplug:1,
+				  li_stopping:1;
 	struct lfsck_rec_lmv_save li_rec_lmv_save[LFSCK_REC_LMV_MAX_DEPTH];
 };
 
diff --git a/lustre/lfsck/lfsck_lib.c b/lustre/lfsck/lfsck_lib.c
index 9d9165f..9b4e021 100644
--- a/lustre/lfsck/lfsck_lib.c
+++ b/lustre/lfsck/lfsck_lib.c
@@ -3087,6 +3087,9 @@ int lfsck_start(const struct lu_env *env, struct dt_device *key,
 	if (unlikely(lfsck == NULL))
 		RETURN(-ENXIO);
 
+	if (unlikely(lfsck->li_stopping))
+		GOTO(put, rc = -ENXIO);
+
 	/* System is not ready, try again later. */
 	if (unlikely(lfsck->li_namespace == NULL ||
 		     lfsck_dev_site(lfsck)->ss_server_fld == NULL))
@@ -3369,6 +3372,10 @@ int lfsck_stop(const struct lu_env *env, struct dt_device *key,
 	}
 
 	spin_lock(&lfsck->li_lock);
+	/* The target is umounted */
+	if (stop && stop->ls_status == LS_PAUSED)
+		lfsck->li_stopping = 1;
+
 	if (thread_is_init(thread) || thread_is_stopped(thread))
 		/* no error if LFSCK stopped already, or not started */
 		GOTO(unlock, rc = 0);