features/worm: new config option to manage deletion of Worm files.

Add a new configuration option worm-files-deletable to
 file-level Worm in order to control behaviour of Worm files upon deletion.

Steps to Test:
1. Add all the configuration options to a volume to activate file-level-worm
2. Option features.worm-files-deletable is set to 1 by default.
3. Create a new file and wait for the retention time to expire.
4. After retention time expires, do an truncate, rename, unlink, link
   or write to send the file in Worm state.
5. After that do `rm -f filename`.
6. The file is successfully removed.
7. Repeat from step 2 by setting features.worm-files-deletable 0.
   This time deletion should not be successful.

Change-Id: Ibc89861ee296e065330b93a9f9606be5da40af31
BUG: 1508898
Signed-off-by: Vishal Pandey <vishpandey2014@gmail.com>

4 files changed, 20 insertions, 1 deletions

diff --git a/xlators/features/read-only/src/read-only.h b/xlators/features/read-only/src/read-only.h
index d0263e74179..aae625f5eaf 100644
--- a/xlators/features/read-only/src/read-only.h
+++ b/xlators/features/read-only/src/read-only.h
@@ -28,6 +28,7 @@ typedef struct {
 typedef struct {
         gf_boolean_t          readonly_or_worm_enabled;
         gf_boolean_t          worm_file;
+        gf_boolean_t          worm_files_deletable;
         uint64_t              reten_period;
         uint64_t              com_period;
         char                  *reten_mode;
diff --git a/xlators/features/read-only/src/worm-helper.c b/xlators/features/read-only/src/worm-helper.c
index 425e48123b1..0770f9d77c4 100644
--- a/xlators/features/read-only/src/worm-helper.c
+++ b/xlators/features/read-only/src/worm-helper.c
@@ -379,7 +379,7 @@ gf_worm_state_transition (xlator_t *this, gf_boolean_t fop_with_fd,
                                       &reten_state, &stbuf);
         }
         if (reten_state.worm && !reten_state.retain &&
-                 op == GF_FOP_UNLINK) {
+                priv->worm_files_deletable && op == GF_FOP_UNLINK) {
                 op_errno = 0;
                 goto out;
         }
diff --git a/xlators/features/read-only/src/worm.c b/xlators/features/read-only/src/worm.c
index a1474b6bc27..cbe7df8e798 100644
--- a/xlators/features/read-only/src/worm.c
+++ b/xlators/features/read-only/src/worm.c
@@ -542,6 +542,8 @@ init (xlator_t *this)
                         uint64, out);
         GF_OPTION_INIT ("auto-commit-period", priv->com_period, uint64, out);
         GF_OPTION_INIT ("retention-mode", priv->reten_mode, str, out);
+        GF_OPTION_INIT ("worm-files-deletable", priv->worm_files_deletable,
+                        bool, out);
 
         this->private = priv;
         ret = 0;
@@ -569,6 +571,8 @@ reconfigure (xlator_t *this, dict_t *options)
                           out);
         GF_OPTION_RECONF ("auto-commit-period", priv->com_period, options,
                           uint64, out);
+        GF_OPTION_RECONF ("worm-files-deletable", priv->worm_files_deletable,
+                          options, bool, out);
         ret = 0;
 out:
         gf_log (this->name, GF_LOG_DEBUG, "returning %d", ret);
@@ -632,6 +636,12 @@ struct volume_options options[] = {
           .description = "When \"on\", activates the file level worm. "
                          "It is turned \"off\" by default."
         },
+        { .key = {"worm-files-deletable"},
+          .type = GF_OPTION_TYPE_BOOL,
+          .default_value = "on",
+          .description = "When \"off\", doesn't allow the Worm files"
+                         "to be deleted. It is turned \"on\" by default."
+        },
         { .key = {"default-retention-period"},
           .type = GF_OPTION_TYPE_TIME,
           .default_value = "120",
diff --git a/xlators/mgmt/glusterd/src/glusterd-volume-set.c b/xlators/mgmt/glusterd/src/glusterd-volume-set.c
index 4b3b9350ef2..7155228ce81 100644
--- a/xlators/mgmt/glusterd/src/glusterd-volume-set.c
+++ b/xlators/mgmt/glusterd/src/glusterd-volume-set.c
@@ -2738,6 +2738,14 @@ struct volopt_map_entry glusterd_volopt_map[] = {
           .op_version  = GD_OP_VERSION_3_8_0,
           .flags      = VOLOPT_FLAG_CLIENT_OPT | VOLOPT_FLAG_XLATOR_OPT
         },
+        { .key         = "features.worm-files-deletable",
+          .voltype     = "features/worm",
+          .option      = "worm-files-deletable",
+          .value       = "on",
+          .validate_fn = validate_boolean,
+          .op_version  = GD_OP_VERSION_3_13_0,
+          .flags       = VOLOPT_FLAG_CLIENT_OPT | VOLOPT_FLAG_XLATOR_OPT
+        },
         { .key         = "features.default-retention-period",
           .voltype     = "features/worm",
           .option      = "default-retention-period",