From: Niu Yawei <yawei.niu@intel.com>
Date: Tue, 3 May 2016 07:18:17 +0000 (-0400)
Subject: LU-8041 mdd: increasing only atime update on close
X-Git-Tag: 2.8.54~66
X-Git-Url: https://git.whamcloud.com/?p=fs%2Flustre-release.git;a=commitdiff_plain;h=c9d4cdd9c8719988f50a76271ce48ef811411fdd

LU-8041 mdd: increasing only atime update on close

The atime update on close should be increasing only, otherwise,
the atime could be overwritten by stale client's atime.

This patch also changed client to clear out the ATTR_ATIME
flag fro close RPC when atime == 0, so that patch client won't
overwrite the unpatched server with 0 atime.

A test case sanity 39p is added to verify that close won't
overwrite atime with zero, and sanity 39l is adjusted as well.

Signed-off-by: Niu Yawei <yawei.niu@intel.com>
Change-Id: I40d1103ddfea184d82170a6795f89ce303a5c14e
Reviewed-on: http://review.whamcloud.com/19932
Reviewed-by: Andreas Dilger <andreas.dilger@intel.com>
Tested-by: Jenkins
Reviewed-by: Jinshan Xiong <jinshan.xiong@intel.com>
Tested-by: Maloo <hpdd-maloo@intel.com>
---

diff --git a/lustre/mdc/mdc_lib.c b/lustre/mdc/mdc_lib.c
index 6f79627..62e1cf9 100644
--- a/lustre/mdc/mdc_lib.c
+++ b/lustre/mdc/mdc_lib.c
@@ -486,13 +486,25 @@ void mdc_getattr_pack(struct ptlrpc_request *req, __u64 valid, __u32 flags,
 
 void mdc_close_pack(struct ptlrpc_request *req, struct md_op_data *op_data)
 {
-        struct mdt_ioepoch *epoch;
-        struct mdt_rec_setattr *rec;
+	struct mdt_ioepoch *epoch;
+	struct mdt_rec_setattr *rec;
 
-        epoch = req_capsule_client_get(&req->rq_pill, &RMF_MDT_EPOCH);
-        rec = req_capsule_client_get(&req->rq_pill, &RMF_REC_REINT);
+	epoch = req_capsule_client_get(&req->rq_pill, &RMF_MDT_EPOCH);
+	rec = req_capsule_client_get(&req->rq_pill, &RMF_REC_REINT);
 
-        mdc_setattr_pack_rec(rec, op_data);
-        mdc_ioepoch_pack(epoch, op_data);
+	mdc_setattr_pack_rec(rec, op_data);
+	/*
+	 * The client will zero out local timestamps when losing the IBITS lock
+	 * so any new RPC timestamps will update the client inode's timestamps.
+	 * There was a defect on the server side which allowed the atime to be
+	 * overwritten by a zeroed-out atime packed into the close RPC.
+	 *
+	 * Proactively clear the MDS_ATTR_ATIME flag in the RPC in this case
+	 * to avoid zeroing the atime on old unpatched servers.  See LU-8041.
+	 */
+	if (rec->sa_atime == 0)
+		rec->sa_valid &= ~MDS_ATTR_ATIME;
+
+	mdc_ioepoch_pack(epoch, op_data);
 	mdc_intent_close_pack(req, op_data);
 }
diff --git a/lustre/mdd/mdd_object.c b/lustre/mdd/mdd_object.c
index 58d51b7..4ad7174 100644
--- a/lustre/mdd/mdd_object.c
+++ b/lustre/mdd/mdd_object.c
@@ -475,9 +475,8 @@ static int mdd_fix_attr(const struct lu_env *env, struct mdd_object *obj,
 	}
 
 	if (la->la_valid == LA_ATIME) {
-		/* This is atime only set for read atime update on close. */
-		if (la->la_atime >= oattr->la_atime &&
-		    la->la_atime < (oattr->la_atime +
+		/* This is an atime-only attribute update for close RPCs. */
+		if (la->la_atime < (oattr->la_atime +
 				mdd_obj2mdd_dev(obj)->mdd_atime_diff))
 			la->la_valid &= ~LA_ATIME;
 		RETURN(0);
diff --git a/lustre/tests/sanity.sh b/lustre/tests/sanity.sh
index f52a1cc..2174b5d 100644
--- a/lustre/tests/sanity.sh
+++ b/lustre/tests/sanity.sh
@@ -3334,29 +3334,27 @@ test_39l() {
 	# test setting directory atime to future
 	touch -a -d @$TEST_39_ATIME $DIR/$tdir
 	local atime=$(stat -c %X $DIR/$tdir)
-	[ "$atime" = $TEST_39_ATIME ] || \
+	[ "$atime" = $TEST_39_ATIME ] ||
 		error "atime is not set to future: $atime, $TEST_39_ATIME"
 
 	# test setting directory atime from future to now
-	local d1=$(date +%s)
-	ls $DIR/$tdir
-	local d2=$(date +%s)
+	local now=$(date +%s)
+	touch -a -d @$now $DIR/$tdir
 
-	cancel_lru_locks mdc
 	atime=$(stat -c %X $DIR/$tdir)
-	[ "$atime" -ge "$d1" -a "$atime" -le "$d2" ] || \
-		error "atime is not updated from future: $atime, $d1<atime<$d2"
+	[ "$atime" -eq "$now"  ] ||
+		error "atime is not updated from future: $atime, $now"
 
 	do_facet $SINGLEMDS lctl set_param -n mdd.*MDT0000*.atime_diff=2
 	sleep 3
 
 	# test setting directory atime when now > dir atime + atime_diff
-	d1=$(date +%s)
+	local d1=$(date +%s)
 	ls $DIR/$tdir
-	d2=$(date +%s)
+	local d2=$(date +%s)
 	cancel_lru_locks mdc
 	atime=$(stat -c %X $DIR/$tdir)
-	[ "$atime" -ge "$d1" -a "$atime" -le "$d2" ] || \
+	[ "$atime" -ge "$d1" -a "$atime" -le "$d2" ] ||
 		error "atime is not updated  : $atime, should be $d2"
 
 	do_facet $SINGLEMDS lctl set_param -n mdd.*MDT0000*.atime_diff=60
@@ -3366,7 +3364,7 @@ test_39l() {
 	ls $DIR/$tdir
 	cancel_lru_locks mdc
 	atime=$(stat -c %X $DIR/$tdir)
-	[ "$atime" -ge "$d1" -a "$atime" -le "$d2" ] || \
+	[ "$atime" -ge "$d1" -a "$atime" -le "$d2" ] ||
 		error "atime is updated to $atime, should remain $d1<atime<$d2"
 
 	do_facet $SINGLEMDS \
@@ -3470,6 +3468,18 @@ test_39p() {
 run_test 39p "remote directory cached attributes updated after create ========"
 
 
+test_39p() { # LU-8041
+	local testdir=$DIR/$tdir
+	mkdir -p $testdir
+	multiop_bg_pause $testdir D_c || error "multiop failed"
+	local multipid=$!
+	cancel_lru_locks mdc
+	kill -USR1 $multipid
+	local atime=$(stat -c %X $testdir)
+	[ "$atime" -ne 0 ] || error "atime is zero"
+}
+run_test 39p "close won't zero out atime"
+
 test_40() {
 	dd if=/dev/zero of=$DIR/$tfile bs=4096 count=1
 	$RUNAS $OPENFILE -f O_WRONLY:O_TRUNC $DIR/$tfile &&