glusterd/snapshot: Inherit the mount options of a original brick

when creating snapshots

When creating a snapshot a LVM is created at the backend and is mounted
under /var/run/gluster/snaps/... However, this mount does not inherit
the mount options for the original brick acting as the parent for the
snap.

If the snap is restored, this could lead to performance degredations,
functional limitations, or in extreme scenarios even potential data
loss.

Change-Id: I67d70fd83430d83dacc5380c6c928e27fb9c9e1b
BUG: 1125180
Signed-off-by: Vijaikumar M <vmallika@redhat.com>
Reviewed-on: http://review.gluster.org/8394
Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>
Tested-by: Krishnan Parthasarathi <kparthas@redhat.com>

1 files changed, 117 insertions, 87 deletions

diff --git a/xlators/mgmt/glusterd/src/glusterd-snapshot.c b/xlators/mgmt/glusterd/src/glusterd-snapshot.c
index bde9aeb3fe3..a86795e224e 100644
--- a/xlators/mgmt/glusterd/src/glusterd-snapshot.c
+++ b/xlators/mgmt/glusterd/src/glusterd-snapshot.c
@@ -995,6 +995,17 @@ glusterd_snapshot_restore_prevalidate (dict_t *dict, char **op_errstr,
                                         "Failed to set %s", key);
                                 goto out;
                         }
+
+                        snprintf (key, sizeof (key),
+                                  "snap%d.brick%d.mnt_opts",
+                                  volcount, brick_count);
+                        ret = dict_set_str (rsp_dict, key,
+                                            brickinfo->mnt_opts);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_ERROR,
+                                        "Failed to set %s", key);
+                                goto out;
+                        }
                 }
 
                 snprintf (key, sizeof (key), "snap%d.brick_count", volcount);
@@ -1311,6 +1322,7 @@ glusterd_snap_create_pre_val_use_rsp_dict (dict_t *dst, dict_t *src)
         char                  *snap_brick_dir        = NULL;
         char                  *snap_device           = NULL;
         char                   key[PATH_MAX]         = "";
+        char                  *value                 = "";
         char                   snapbrckcnt[PATH_MAX] = "";
         char                   snapbrckord[PATH_MAX] = "";
         int                    ret                   = -1;
@@ -1379,6 +1391,44 @@ glusterd_snap_create_pre_val_use_rsp_dict (dict_t *dst, dict_t *src)
                         }
 
                         snprintf (key, sizeof(key) - 1,
+                                  "vol%"PRId64".fstype%"PRId64, i+1, j);
+                        ret = dict_get_str (src, key, &value);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_WARNING,
+                                        "Unable to fetch %s", key);
+                                continue;
+                        }
+
+                        snprintf (key, sizeof(key) - 1,
+                                  "vol%"PRId64".fstype%"PRId64, i+1,
+                                  brick_order);
+                        ret = dict_set_dynstr_with_alloc (dst, key, value);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_ERROR,
+                                        "Failed to set %s", key);
+                                goto out;
+                        }
+
+                        snprintf (key, sizeof(key) - 1,
+                                  "vol%"PRId64".mnt_opts%"PRId64, i+1, j);
+                        ret = dict_get_str (src, key, &value);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_WARNING,
+                                        "Unable to fetch %s", key);
+                                continue;
+                        }
+
+                        snprintf (key, sizeof(key) - 1,
+                                  "vol%"PRId64".mnt_opts%"PRId64, i+1,
+                                  brick_order);
+                        ret = dict_set_dynstr_with_alloc (dst, key, value);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_ERROR,
+                                        "Failed to set %s", key);
+                                goto out;
+                        }
+
+                        snprintf (key, sizeof(key) - 1,
                                   "vol%"PRId64".brick_snapdevice%"PRId64,
                                   i+1, j);
                         ret = dict_get_ptr (src, key,
@@ -1527,6 +1577,21 @@ glusterd_snap_restore_use_rsp_dict (dict_t *dst, dict_t *src)
                                         "Failed to set %s", key);
                                 goto out;
                         }
+
+                        snprintf (key, sizeof (key),
+                                  "snap%d.brick%d.mnt_opts", i, j);
+                        ret = dict_get_str (src, key, &strvalue);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_ERROR,
+                                        "Failed to get %s", key);
+                                goto out;
+                        }
+                        ret = dict_set_dynstr_with_alloc (dst, key, strvalue);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_DEBUG,
+                                        "Failed to set %s", key);
+                                goto out;
+                        }
                 }
         }
 
@@ -1918,6 +1983,34 @@ glusterd_snapshot_create_prevalidate (dict_t *dict, char **op_errstr,
                         }
                         device = NULL;
 
+                        ret = glusterd_update_mntopts (brickinfo->path,
+                                                       brickinfo);
+                        if (ret) {
+                                 gf_log (this->name, GF_LOG_ERROR, "Failed to "
+                                         "update mount options for %s brick",
+                                         brickinfo->path);
+                        }
+
+                        snprintf (key, sizeof(key), "vol%"PRId64".fstype%"
+                                  PRId64, i, brick_count);
+                        ret = dict_set_dynstr_with_alloc (rsp_dict, key,
+                                                          brickinfo->fstype);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_ERROR,
+                                        "Failed to set %s", key);
+                                goto out;
+                        }
+
+                        snprintf (key, sizeof(key), "vol%"PRId64".mnt_opts%"
+                                  PRId64, i, brick_count);
+                        ret = dict_set_dynstr_with_alloc (rsp_dict, key,
+                                                          brickinfo->mnt_opts);
+                        if (ret) {
+                                gf_log (this->name, GF_LOG_ERROR,
+                                        "Failed to set %s", key);
+                                goto out;
+                        }
+
                         snprintf (key, sizeof(key), "vol%"PRId64".brickdir%"PRId64, i,
                                   brick_count);
                         ret = dict_set_dynstr_with_alloc (rsp_dict, key,
@@ -3868,9 +3961,7 @@ glusterd_snap_brick_create (glusterd_volinfo_t *snap_volinfo,
                         MS_MGC_VAL, "nouuid");
            But for now, mounting using runner apis.
         */
-        ret = glusterd_mount_lvm_snapshot (brickinfo->device_path,
-                                           snap_brick_mount_path,
-                                           brickinfo->fstype);
+        ret = glusterd_mount_lvm_snapshot (brickinfo, snap_brick_mount_path);
         if (ret) {
                 gf_log (this->name, GF_LOG_ERROR,
                         "Failed to mount lvm snapshot.");
@@ -3910,74 +4001,6 @@ out:
         return ret;
 }
 
-/* This function will update the backend file-system
- * type in origin and snap brickinfo. This will be later
- * used to perform file-system specific operation during
- * LVM snapshot.
- *
- * @param orig_brickinfo        brickinfo of origin volume
- * @param snap_brickinfo        brickinfo of snap volume
- *
- * @return 0 on success and -1 on failure
- */
-int
-glusterd_update_fstype (char *orig_brick_path,
-                        glusterd_brickinfo_t *snap_brickinfo,
-                        char *fstype, size_t fslen)
-{
-        int32_t               ret               = -1;
-        char                 *mnt_pt            = NULL;
-        char                  buff [PATH_MAX]   = "";
-        char                  msg [PATH_MAX]    = "";
-        char                 *cmd               = NULL;
-        struct mntent        *entry             = NULL;
-        struct mntent         save_entry        = {0,};
-        runner_t              runner            = {0,};
-        xlator_t             *this              = NULL;
-
-        this = THIS;
-        GF_ASSERT (this);
-        GF_ASSERT (orig_brick_path);
-        GF_ASSERT (snap_brickinfo);
-        GF_ASSERT (fstype);
-
-        /* If the file-system type is not set then set the file-system type
-         * in origin brickinfo */
-        if (0 == fstype [0]) {
-                ret = glusterd_get_brick_root (orig_brick_path, &mnt_pt);
-                if (ret) {
-                        gf_log (this->name, GF_LOG_ERROR, "getting the root "
-                                "of the brick (%s) failed ",
-                                orig_brick_path);
-                        goto out;
-                }
-
-                entry = glusterd_get_mnt_entry_info (mnt_pt, buff,
-                                                sizeof (buff), &save_entry);
-                if (!entry) {
-                        gf_log (this->name, GF_LOG_ERROR, "getting the mount "
-                                "entry for the brick (%s) failed",
-                                orig_brick_path);
-                        ret = -1;
-                        goto out;
-                }
-
-                /* Update the origin brickinfo with the backend file-system
-                 * type */
-                snprintf (fstype, fslen, "%s",
-                          entry->mnt_type);
-        }
-
-        /* Update the file-system type for snap brickinfo */
-        snprintf (snap_brickinfo->fstype, sizeof (snap_brickinfo->fstype),
-                  "%s", fstype);
-
-        ret = 0;
-out:
-        GF_FREE (mnt_pt);
-        return ret;
-}
-
 static int32_t
 glusterd_add_brick_to_snap_volume (dict_t *dict, dict_t *rsp_dict,
                                     glusterd_volinfo_t  *snap_vol,
@@ -3985,6 +4008,7 @@ glusterd_add_brick_to_snap_volume (dict_t *dict, dict_t *rsp_dict,
                                     int64_t volcount, int32_t brick_count)
 {
         char                    key[PATH_MAX]                   = "";
+        char                   *value                           = NULL;
         char                   *snap_brick_dir                  = NULL;
         char                    snap_brick_path[PATH_MAX]       = "";
         char                   *snap_device                     = NULL;
@@ -4017,22 +4041,28 @@ glusterd_add_brick_to_snap_volume (dict_t *dict, dict_t *rsp_dict,
                 goto out;
         }
 
-        /* Update fstype for the local bricks only */
-        if (!uuid_compare (original_brickinfo->uuid, MY_UUID)) {
-                /* Update the backend file-system type of snap brick in
-                 * snap volinfo. */
-                ret = glusterd_update_fstype
-                                          (original_brickinfo->path,
-                                           snap_brickinfo,
-                                           original_brickinfo->fstype,
-                                           sizeof(original_brickinfo->fstype));
-                if (ret) {
-                        gf_log (this->name, GF_LOG_ERROR, "Failed to update "
-                                "file-system type for %s brick",
-                                snap_brickinfo->path);
-                        /* We should not fail snapshot operation if we fail to
-                         * get the file-system type */
-                }
+        snprintf (key, sizeof(key) - 1, "vol%"PRId64".fstype%d", volcount,
+                  brick_count);
+        ret = dict_get_str (dict, key, &value);
+        if (!ret) {
+                /* Update the fstype in original brickinfo as well */
+                strcpy (original_brickinfo->fstype, value);
+                strcpy (snap_brickinfo->fstype, value);
+        } else {
+                if (is_origin_glusterd (dict) == _gf_true)
+                        add_missed_snap = _gf_true;
+        }
+
+        snprintf (key, sizeof(key) - 1, "vol%"PRId64".mnt_opts%d", volcount,
+                  brick_count);
+        ret = dict_get_str (dict, key, &value);
+        if (!ret) {
+                /* Update the mnt_opts in original brickinfo as well */
+                strcpy (original_brickinfo->mnt_opts, value);
+                strcpy (snap_brickinfo->mnt_opts, value);
+        } else {
+                if (is_origin_glusterd (dict) == _gf_true)
+                        add_missed_snap = _gf_true;
         }
 
         snprintf (key, sizeof(key) - 1, "vol%"PRId64".brickdir%d", volcount,