[glusterd/snapshot] snapshot create force option

Implement force option in snapshot create i.e

1) Creation of snapshot fails if the original volume
bricks are down
2) With a force option creation of snapshot will continue
even if the original volume bricks are down.

This was the fix for bugs 1089527 and 1083502

Change-Id: I8de0242adf8ee0af00db9fa8701d86fabc12e7fc
BUG: 1090042
Signed-off-by: Joseph Fernandes <josferna@redhat.com>
Reviewed-on: http://review.gluster.org/7520
Reviewed-by: Atin Mukherjee <amukherj@redhat.com>
Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Vijay Bellur <vbellur@redhat.com>

4 files changed, 86 insertions, 18 deletions

diff --git a/cli/src/cli-cmd-parser.c b/cli/src/cli-cmd-parser.c
index 5fdb9d08a74..de0654a744b 100644
--- a/cli/src/cli-cmd-parser.c
+++ b/cli/src/cli-cmd-parser.c
@@ -2986,12 +2986,13 @@ out:
  */
 int
 cli_snap_create_parse (dict_t *dict, const char **words, int wordcount) {
-        uint64_t        i               =        0;
+        uint64_t        i               =       0;
         int             ret             =       -1;
-        uint64_t        volcount        =        0;
-        char            key[PATH_MAX]   =        "";
+        uint64_t        volcount        =       0;
+        char            key[PATH_MAX]   =       "";
         char            *snapname       =       NULL;
-        unsigned int    cmdi            =        2;
+        unsigned int    cmdi            =       2;
+        int             flags           =       0;
         /* cmdi is command index, here cmdi is "2" (gluster snapshot create)*/
 
         GF_ASSERT (words);
@@ -3107,18 +3108,15 @@ cli_snap_create_parse (dict_t *dict, const char **words, int wordcount) {
                  */
         }
 
-        if ((strcmp (words[i], "force") != 0)) {
+        if (strcmp (words[i], "force") == 0) {
+                flags = GF_CLI_FLAG_OP_FORCE;
+
+        } else {
                 ret = -1;
                 cli_err ("Invalid Syntax.");
                 gf_log ("cli", GF_LOG_ERROR, "Invalid Syntax");
                 goto out;
         }
-        ret = dict_set_int8 (dict, "snap-force", 1);
-        if (ret) {
-                gf_log ("cli", GF_LOG_ERROR, "Could not save "
-                        "snap force option");
-                goto out;
-        }
 
         /* Check if the command has anything after "force" keyword */
         if (++i < wordcount) {
@@ -3130,6 +3128,15 @@ cli_snap_create_parse (dict_t *dict, const char **words, int wordcount) {
         ret = 0;
 
 out:
+        if(ret == 0) {
+                /*Adding force flag in either of the case i.e force set
+                 * or unset*/
+                ret = dict_set_int32 (dict, "flags", flags);
+                if (ret) {
+                        gf_log ("cli", GF_LOG_ERROR, "Could not save "
+                                "snap force option");
+                }
+        }
         return ret;
 }
 
diff --git a/tests/bugs/bug-1090042.t b/tests/bugs/bug-1090042.t
new file mode 100755
index 00000000000..364d8b2d66b
--- /dev/null
+++ b/tests/bugs/bug-1090042.t
@@ -0,0 +1,30 @@
+#!/bin/bash
+
+. $(dirname $0)/../include.rc
+. $(dirname $0)/../volume.rc
+. $(dirname $0)/../snapshot.rc
+
+cleanup;
+
+TEST init_n_bricks 3;
+TEST setup_lvm 3;
+TEST glusterd;
+
+TEST $CLI volume create $V0 replica 3 $H0:$L1 $H0:$L2 $H0:$L3;
+TEST $CLI volume start $V0;
+
+TEST kill_brick $V0 $H0 $L1;
+
+#Normal snap create should fail
+TEST !  $CLI snapshot create ${V0}_snap1 $V0;
+TEST !  snapshot_exists 0 ${V0}_snap1;
+
+#Force snap create should succeed
+TEST  $CLI snapshot create ${V0}_snap1 $V0 force;
+TEST  snapshot_exists 0 ${V0}_snap1;
+
+#Delete the created snap
+TEST  $CLI snapshot delete ${V0}_snap1;
+TEST  ! snapshot_exists 0 ${V0}_snap1;
+
+cleanup;
diff --git a/tests/snapshot.rc b/tests/snapshot.rc
index 87ea0df9190..37c250344f1 100755
--- a/tests/snapshot.rc
+++ b/tests/snapshot.rc
@@ -5,6 +5,17 @@ LVM_PREFIX="patchy_snap"
 LVM_COUNT=0
 VHD_SIZE="1G"
 
+#This function will init B# bricks
+#This is used when launch_cluster is
+#not called to init B#. Call it before
+#setup_lvm
+function init_n_bricks() {
+    local count=$1
+    for i in `seq 1 $count`; do
+        eval "B$i=/d/backends/$i"
+    done
+}
+
 function init_lvm() {
     if [ "$1" == "" ]; then
         echo "Error: Invalid argument supplied"
diff --git a/xlators/mgmt/glusterd/src/glusterd-snapshot.c b/xlators/mgmt/glusterd/src/glusterd-snapshot.c
index 374397e7c4c..c88444098c7 100644
--- a/xlators/mgmt/glusterd/src/glusterd-snapshot.c
+++ b/xlators/mgmt/glusterd/src/glusterd-snapshot.c
@@ -918,6 +918,7 @@ glusterd_snapshot_create_prevalidate (dict_t *dict, char **op_errstr,
         gf_loglevel_t          loglevel                  = GF_LOG_ERROR;
         glusterd_conf_t       *conf                      = NULL;
         int64_t                effective_max_limit       = 0;
+        int                    flags                     = 0;
 
         this = THIS;
         GF_ASSERT (op_errstr);
@@ -943,6 +944,12 @@ glusterd_snapshot_create_prevalidate (dict_t *dict, char **op_errstr,
                 goto out;
         }
 
+        ret = dict_get_int32 (dict, "flags", &flags);
+        if (ret) {
+                gf_log (this->name, GF_LOG_ERROR, "Unable to get flags");
+                goto out;
+        }
+
         if (glusterd_find_snap_by_name (snapname)) {
                 ret = -1;
                 snprintf (err_str, sizeof (err_str), "Snap %s already exists",
@@ -1026,13 +1033,26 @@ glusterd_snapshot_create_prevalidate (dict_t *dict, char **op_errstr,
                         }
 
                         if (!glusterd_is_brick_started (brickinfo)) {
-                                gf_log (this->name, GF_LOG_WARNING,
-                                        "brick %s:%s is not started",
-                                        brickinfo->hostname,
-                                        brickinfo->path);
-                                brick_order++;
-                                brick_count++;
-                                continue;
+                                if(flags & GF_CLI_FLAG_OP_FORCE) {
+                                        gf_log (this->name, GF_LOG_WARNING,
+                                                "brick %s:%s is not started",
+                                                brickinfo->hostname,
+                                                brickinfo->path);
+                                        brick_order++;
+                                        brick_count++;
+                                        continue;
+                                }
+
+                                snprintf (err_str, sizeof (err_str),
+                                          "brick %s:%s is not started. "
+                                          "Please start the stopped brick "
+                                          "and then issue snapshot create "
+                                          "command or use [force] option in "
+                                          "snapshot create to override this "
+                                          "behavior.", brickinfo->hostname,
+                                          brickinfo->path);
+                                ret = -1;
+                                goto out;
                         }
 
                         device = glusterd_get_brick_mount_details (brickinfo);