afr: remove stale index entries

Backport of http://review.gluster.org/9714

Problem:
During pre-op phase, the index xlator
1. Creates the entry inside .glusterfs/indices/xattrop
2. Winds the xattrop fop to posix to mark dirty/pending changelogs.
If the brick crashes after 1, the xattrop entry becomes stale and never
gets removed by shd during subsequent crawls because there is nothing to
heal (changelogs are zero).

Though the stale entry does not get displayed in the output of 'heal info'
command, it nevertheless stays there forever unless a new write tansaction
is performed on the file.

Fix:
During index self-heal if afr xattrs are found to be clean (indicated by
ret value of 2 on a call to afr_shd_selfheal(), send a dummy
post-op with all 0s for the xattr values, which makes the index xlator
to unlink the stale entry.

Change-Id: Iffb171e40490abd8d44df09ccc058b5da67baafe
BUG: 1203081
Signed-off-by: Ravishankar N <ravishankar@redhat.com>
Reviewed-on: http://review.gluster.org/9920
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
Reviewed-by: Raghavendra Bhat <raghavendra@redhat.com>

9 files changed, 137 insertions, 57 deletions

diff --git a/tests/afr.rc b/tests/afr.rc
index 938f9c07ab2..50067274d89 100644
--- a/tests/afr.rc
+++ b/tests/afr.rc
@@ -73,11 +73,9 @@ function is_file_heal_done {
 
 function count_sh_entries()
 {
-    val1=0
-    for g in `ls $1/.glusterfs/indices/xattrop`
-    do
-	val1=$(( val1 + 1 ))
-    done
-
-    echo $val1;
+        ls $1/.glusterfs/indices/xattrop | grep -v "xattrop-" | wc -l
+}
+function count_index_entries()
+{
+    ls $1/.glusterfs/indices/xattrop | wc -l
 }
diff --git a/tests/bugs/bug-1015990-rep.t b/tests/bugs/bug-1015990-rep.t
index bca0d7aff07..5a6564d9f7a 100755
--- a/tests/bugs/bug-1015990-rep.t
+++ b/tests/bugs/bug-1015990-rep.t
@@ -32,8 +32,6 @@ sleep 5
 
 for  i in  {1..100}; do echo "STRING" > $M0/File$i; done
 
-brick_2_sh_entries=$(count_sh_entries $B0/$V0"2")
-brick_4_sh_entries=$(count_sh_entries $B0/$V0"4")
 
 command_output=$(gluster volume heal $V0 statistics heal-count replica $H0:$B0/$V0"1")
 
@@ -58,19 +56,9 @@ brick_2_entries_count=$count
 
 
 xattrop_count_brick_2=$(count_sh_entries $B0/$V0"2")
-##Remove the count of the xattrop-gfid entry count as it does not contribute
-##to the number of files to be healed
 
-sub_val=1
-xattrop_count_brick_2=$(($xattrop_count_brick_2-$sub_val))
+EXPECT $brick_2_entries_count echo $xattrop_count_brick_2
 
-ret=0
-if [ "$xattrop_count_brick_2" -eq "$brick_2_entries_count" ]
-        then
-                ret=$(($ret + $sub_val))
-fi
-
-EXPECT "1" echo $ret
 ## Finish up
 TEST $CLI volume stop $V0;
 EXPECT 'Stopped' volinfo_field $V0 'Status';
diff --git a/tests/bugs/bug-1015990.t b/tests/bugs/bug-1015990.t
index 165af5168a0..43b7d6c585c 100755
--- a/tests/bugs/bug-1015990.t
+++ b/tests/bugs/bug-1015990.t
@@ -54,36 +54,10 @@ done <<< "$command_output"
 brick_2_entries_count=$(($count-$value))
 brick_4_entries_count=$value
 
-
 xattrop_count_brick_2=$(count_sh_entries $B0/$V0"2")
-##Remove the count of the xattrop-gfid entry count as it does not contribute
-##to the number of files to be healed
-
-sub_val=1
-xattrop_count_brick_2=$(($xattrop_count_brick_2-$sub_val))
-
 xattrop_count_brick_4=$(count_sh_entries $B0/$V0"4")
-##Remove xattrop-gfid entry count
-
-xattrop_count_brick_4=$(($xattrop_count_brick_4-$sub_val))
-
-
-ret=0
-if [ "$xattrop_count_brick_2" -eq "$brick_2_entries_count" ]
-        then
-                ret=$(($ret + $sub_val))
-fi
-
-EXPECT "1" echo $ret
-
-
-ret=0
-if [ "$xattrop_count_brick_4" -eq "$brick_4_entries_count" ]
-        then
-                ret=$(($ret + $sub_val))
-fi
-
-EXPECT "1" echo $ret
+EXPECT $brick_2_entries_count echo $xattrop_count_brick_2
+EXPECT $brick_4_entries_count echo $xattrop_count_brick_4
 
 ## Finish up
 TEST $CLI volume stop $V0;
diff --git a/tests/bugs/bug-1101647.t b/tests/bugs/bug-1101647.t
index ccfa7e2138b..2337dac6feb 100644
--- a/tests/bugs/bug-1101647.t
+++ b/tests/bugs/bug-1101647.t
@@ -13,13 +13,13 @@ TEST $CLI volume start $V0;
 TEST glusterfs --volfile-id=/$V0 --volfile-server=$H0 $M0 --attribute-timeout=0 --entry-timeout=0
 EXPECT_WITHIN 20 "Y" glustershd_up_status
 
-#Create base entry in indices/xattrop and indices/base_indices_holder
+#Create base entry in indices/xattrop
 echo "Data">$M0/file
 
 TEST $CLI volume heal $V0
-#Entries from indices/xattrop and indices/base_indices_holder should not be cleared after a heal.
-EXPECT 1 count_sh_entries  $B0/$V0"1"
-EXPECT 1 count_sh_entries  $B0/$V0"2"
+#Entries from indices/xattrop should not be cleared after a heal.
+EXPECT 1 count_index_entries  $B0/$V0"1"
+EXPECT 1 count_index_entries  $B0/$V0"2"
 
 TEST kill_brick $V0 $H0 $B0/${V0}2
 echo "More data">>$M0/file
diff --git a/tests/bugs/bug-1190069-afr-stale-index-entries.t b/tests/bugs/bug-1190069-afr-stale-index-entries.t
new file mode 100644
index 00000000000..8d2871e8270
--- /dev/null
+++ b/tests/bugs/bug-1190069-afr-stale-index-entries.t
@@ -0,0 +1,57 @@
+#!/bin/bash
+. $(dirname $0)/../include.rc
+. $(dirname $0)/../volume.rc
+. $(dirname $0)/../afr.rc
+cleanup;
+
+#Stale entries in xattrop folder for files which do not need heal must be removed during the next index heal crawl.
+
+TEST glusterd;
+TEST pidof glusterd;
+TEST $CLI volume create $V0 replica 2 $H0:$B0/${V0}{0,1};
+TEST $CLI volume set $V0 cluster.self-heal-daemon off
+TEST $CLI volume start $V0;
+TEST glusterfs --volfile-id=/$V0 --volfile-server=$H0 $M0 --attribute-timeout=0 --entry-timeout=0
+TEST `echo hello>$M0/datafile`
+TEST touch $M0/mdatafile
+
+#Create split-brain and reset the afr xattrs, so that we have only the entry inside xattrop folder.
+#This is to simulate the case where the brick crashed just before pre-op happened, but index xlator created the entry inside xattrop folder.
+
+#Create data, metadata SB.
+TEST kill_brick $V0 $H0 $B0/$V0"1"
+TEST stat $M0/datafile
+TEST `echo append>>$M0/datafile`
+TEST chmod +x $M0/mdatafile
+TEST $CLI volume start $V0 force
+EXPECT_WITHIN $CHILD_UP_TIMEOUT '1' afr_child_up_status_meta $M0 $V0-replicate-0 1
+TEST kill_brick $V0 $H0 $B0/$V0"0"
+TEST stat $M0/datafile
+TEST `echo append>>$M0/datafile`
+TEST chmod +x $M0/mdatafile
+TEST $CLI volume start $V0 force
+EXPECT_WITHIN $CHILD_UP_TIMEOUT '1' afr_child_up_status_meta $M0 $V0-replicate-0 0
+TEST ! cat $M0/datafile
+
+TEST $CLI volume set $V0 cluster.self-heal-daemon on
+EXPECT_WITHIN $PROCESS_UP_TIMEOUT "Y" glustershd_up_status
+EXPECT_WITHIN $CHILD_UP_TIMEOUT '1' afr_child_up_status_in_shd $V0 0
+EXPECT_WITHIN $CHILD_UP_TIMEOUT '1' afr_child_up_status_in_shd $V0 1
+
+TEST $CLI volume heal $V0
+EXPECT_WITHIN $HEAL_TIMEOUT '2' echo $(count_sh_entries $B0/$V0"0")
+EXPECT_WITHIN $HEAL_TIMEOUT '2' echo $(count_sh_entries $B0/$V0"1")
+
+#Reset xattrs and trigger heal.
+TEST setfattr -n trusted.afr.$V0-client-1 -v 0x000000000000000000000000 $B0/${V0}0/datafile
+TEST setfattr -n trusted.afr.$V0-client-0 -v 0x000000000000000000000000 $B0/${V0}1/datafile
+
+TEST setfattr -n trusted.afr.$V0-client-1 -v 0x000000000000000000000000 $B0/${V0}0/mdatafile
+TEST setfattr -n trusted.afr.$V0-client-0 -v 0x000000000000000000000000 $B0/${V0}1/mdatafile
+
+TEST $CLI volume heal $V0
+EXPECT_WITHIN $HEAL_TIMEOUT "0" afr_get_pending_heal_count $V0
+EXPECT_WITHIN $HEAL_TIMEOUT '0' echo $(count_sh_entries $B0/$V0"0")
+EXPECT_WITHIN $HEAL_TIMEOUT '0' echo $(count_sh_entries $B0/$V0"1")
+
+cleanup
diff --git a/tests/bugs/bug-874498.t b/tests/bugs/bug-874498.t
index 843698d2a61..19c09e78cad 100644
--- a/tests/bugs/bug-874498.t
+++ b/tests/bugs/bug-874498.t
@@ -56,7 +56,7 @@ TEST $CLI volume heal $V0
 
 
 ##Expected number of entries are 0 in the .glusterfs/indices/xattrop directory
-EXPECT_WITHIN $HEAL_TIMEOUT '1' count_sh_entries $FILEN;
+EXPECT_WITHIN $HEAL_TIMEOUT '0' count_sh_entries $FILEN;
 
 TEST $CLI volume stop $V0;
 TEST $CLI volume delete $V0;
diff --git a/tests/bugs/bug-957877.t b/tests/bugs/bug-957877.t
index 52bbd62ec2a..90836679de9 100644
--- a/tests/bugs/bug-957877.t
+++ b/tests/bugs/bug-957877.t
@@ -23,7 +23,7 @@ EXPECT_WITHIN $CHILD_UP_TIMEOUT "1" afr_child_up_status_in_shd $V0 1
 TEST $CLI volume heal $V0
 
 # Wait for self-heal to complete
-EXPECT_WITHIN $HEAL_TIMEOUT '1' count_sh_entries $BRICK;
+EXPECT_WITHIN $HEAL_TIMEOUT '0' count_sh_entries $BRICK;
 
 TEST getfattr -n "user.foo" $B0/${V0}0/f1;
 
diff --git a/xlators/cluster/afr/src/afr-self-heal-common.c b/xlators/cluster/afr/src/afr-self-heal-common.c
index c6b14e1def7..7fb6e2b9dc4 100644
--- a/xlators/cluster/afr/src/afr-self-heal-common.c
+++ b/xlators/cluster/afr/src/afr-self-heal-common.c
@@ -1141,6 +1141,11 @@ afr_selfheal_do (call_frame_t *frame, xlator_t *this, uuid_t gfid)
 	if (ret)
 		goto out;
 
+        if (!(data_selfheal || metadata_selfheal || entry_selfheal)) {
+                ret = 2;
+                goto out;
+        }
+
 	if (data_selfheal)
                 data_ret = afr_selfheal_data (frame, this, inode);
 
@@ -1169,9 +1174,12 @@ out:
         return ret;
 }
 /*
- * This is the entry point for healing a given GFID
- * The function returns 0 if self-heal was successful, appropriate errno
- * in case of a failure and 1 in case self-heal was never needed on the gfid.
+ * This is the entry point for healing a given GFID. The return values for this
+ * function are as follows:
+ * '0' if the self-heal is successful
+ * '1' if the afr-xattrs are non-zero (due to on-going IO) and no heal is needed
+ * '2' if the afr-xattrs are all-zero and no heal is needed
+ * $errno if the heal on the gfid failed.
  */
 
 int
diff --git a/xlators/cluster/afr/src/afr-self-heald.c b/xlators/cluster/afr/src/afr-self-heald.c
index 992ed28b994..7c235aca429 100644
--- a/xlators/cluster/afr/src/afr-self-heald.c
+++ b/xlators/cluster/afr/src/afr-self-heald.c
@@ -313,6 +313,53 @@ afr_shd_index_purge (xlator_t *subvol, inode_t *inode, char *name)
 	return ret;
 }
 
+void
+afr_shd_zero_xattrop (xlator_t *this, uuid_t gfid)
+{
+
+        call_frame_t *frame = NULL;
+        inode_t *inode = NULL;
+        afr_private_t *priv = NULL;
+        dict_t  *xattr = NULL;
+        int ret = 0;
+        int i = 0;
+        int raw[AFR_NUM_CHANGE_LOGS] = {0};
+
+        priv = this->private;
+        frame = afr_frame_create (this);
+        if (!frame)
+                goto out;
+        inode = afr_inode_find (this, gfid);
+        if (!inode)
+                goto out;
+        xattr = dict_new();
+        if (!xattr)
+                goto out;
+        ret = dict_set_static_bin (xattr, AFR_DIRTY, raw,
+                                   sizeof(int) * AFR_NUM_CHANGE_LOGS);
+        if (ret)
+                goto out;
+        for (i = 0; i < priv->child_count; i++) {
+                ret = dict_set_static_bin (xattr, priv->pending_key[i], raw,
+                                           sizeof(int) * AFR_NUM_CHANGE_LOGS);
+                if (ret)
+                        goto out;
+        }
+
+        /*Send xattrop to all bricks. Doing a lookup to see if bricks are up or
+        * has valid repies for this gfid seems a bit of an overkill.*/
+        for (i = 0; i < priv->child_count; i++)
+                afr_selfheal_post_op (frame, this, inode, i, xattr);
+
+out:
+        if (frame)
+                AFR_STACK_DESTROY (frame);
+        if (inode)
+                inode_unref (inode);
+        if (xattr)
+                dict_unref (xattr);
+        return;
+}
 
 int
 afr_shd_selfheal_name (struct subvol_healer *healer, int child, uuid_t parent,
@@ -480,6 +527,14 @@ afr_shd_index_sweep (struct subvol_healer *healer)
 				afr_shd_index_purge (subvol, fd->inode,
 						     entry->d_name);
 			}
+                        if (ret == 2)
+                        /* If bricks crashed in pre-op after creating
+                         * indices/xattrop link but before setting afr
+                         * changelogs, we end up with stale xattrop links but
+                         * zero changelogs. Remove such entries by sending a
+                         * post-op with zero changelogs.
+                         */
+                                afr_shd_zero_xattrop (healer->this, gfid);
                         ret = 0;
 		}