hooks: add a script to stat the subdirs in add-brick

The subdirectories are expected to be present for a subdir
mount to be successful. If not, the client_handshake()
itself fails to succeed. When a volume is about to get
mounted first time, this is easier to handle, as if the
directory is not present in one brick, then its mostly
not present in any other brick. In case of add-brick,
the directory is not present in new brick, and there is
no chance of healing it from the subdirectory mount, as
in those clients, the subdir itself will be 'root' ('/')
of the filesystem. Hence we need a volume mount to heal
the directory before connections can succeed.

This patch does take care of that by healing the directories
which are expected to be mounted as subdirectories from the
volume level mount point.

Change-Id: I2c2ac7b7567fe209aaa720006d09b68584d0dd14
BUG: 1549915
Signed-off-by: Amar Tumballi <amarts@redhat.com>

2 files changed, 88 insertions, 2 deletions

diff --git a/extras/hook-scripts/add-brick/post/Makefile.am b/extras/hook-scripts/add-brick/post/Makefile.am
index c1fcf50f05f..bfc0c1cf080 100644
--- a/extras/hook-scripts/add-brick/post/Makefile.am
+++ b/extras/hook-scripts/add-brick/post/Makefile.am
@@ -1,6 +1,6 @@
-EXTRA_DIST = disabled-quota-root-xattr-heal.sh
+EXTRA_DIST = disabled-quota-root-xattr-heal.sh S13create-subdir-mounts.sh
 
 hookdir = $(GLUSTERD_WORKDIR)/hooks/1/add-brick/post/
 if WITH_SERVER
-hook_SCRIPTS = disabled-quota-root-xattr-heal.sh
+hook_SCRIPTS = disabled-quota-root-xattr-heal.sh S13create-subdir-mounts.sh
 endif
diff --git a/extras/hook-scripts/add-brick/post/S13create-subdir-mounts.sh b/extras/hook-scripts/add-brick/post/S13create-subdir-mounts.sh
new file mode 100755
index 00000000000..95e624e3442
--- /dev/null
+++ b/extras/hook-scripts/add-brick/post/S13create-subdir-mounts.sh
@@ -0,0 +1,86 @@
+#!/bin/bash
+
+##---------------------------------------------------------------------------
+## This script runs the self-heal of the directories which are expected to
+## be present as they are mounted as subdirectory mounts.
+##---------------------------------------------------------------------------
+
+MOUNT_DIR=`mktemp -d -t ${0##*/}.XXXXXX`;
+OPTSPEC="volname:,go-workdir"
+PROGNAME="add-brick-create-subdir"
+VOL_NAME=test
+GLUSTERD_WORKDIR="/var/lib/glusterd"
+
+cleanup_mountpoint ()
+{
+        umount -f $MOUNT_DIR;
+        if [ 0 -ne $? ]
+        then
+                return $?
+        fi
+
+        rmdir $MOUNT_DIR;
+        if [ 0 -ne $? ]
+        then
+                return $?
+        fi
+}
+
+##------------------------------------------
+## Parse the arguments
+##------------------------------------------
+ARGS=$(getopt -l $OPTSPEC  -name $PROGNAME $@)
+eval set -- "$ARGS"
+
+while true;
+do
+    case $1 in
+        --volname)
+            shift
+            VOL_NAME=$1
+            ;;
+        --gd-workdir)
+            shift
+            GLUSTERD_WORKDIR=$1
+            ;;
+	--version)
+	    shift
+	    ;;
+	--volume-op)
+	    shift
+	    ;;
+	*)
+	    shift
+	    break
+	    ;;
+    esac
+    shift
+done
+
+## See if we have any subdirs to be healed before going further
+subdirs=$(grep 'auth.allow' ${GLUSTERD_WORKDIR}/vols/${VOL_NAME}/info | cut -f2 -d'=' | tr ',' '\n' | cut -f1 -d'(');
+
+if [ -z ${subdirs} ]; then
+    rmdir $MOUNT_DIR;
+    exit 0;
+fi
+
+##----------------------------------------
+## Mount the volume in temp directory.
+## -----------------------------------
+glusterfs -s localhost --volfile-id=$VOL_NAME --client-pid=-50 $MOUNT_DIR;
+if [ 0 -ne $? ]
+then
+    exit $?;
+fi
+
+## -----------------------------------
+# Do the 'stat' on all the directory for now. Ideal fix is to look at subdir
+# list from 'auth.allow' option and only stat them.
+for subdir in ${subdirs}
+do
+    stat ${MOUNT_DIR}/${subdir} > /dev/null;
+done
+
+## Clean up and exit
+cleanup_mountpoint;