glusterd/snapshot: Return correct errno in events of failure - PATCH 1

       Backport of patch http://review.gluster.org/#/c/10313/

RETCODE              ERROR
-------------------------------------------
30800                Internal Error
30801                Another Transaction In Progress

>Change-Id: Ica7fd2e513b2c28717b6df73cfb2667725dbf057
>BUG: 1226117
>Signed-off-by: Avra Sengupta <asengupt@redhat.com>
>Reviewed-on: http://review.gluster.org/10313
>Reviewed-by: Rajesh Joseph <rjoseph@redhat.com>
>Tested-by: Gluster Build System <jenkins@build.gluster.com>
>Tested-by: NetBSD Build System
>Reviewed-by: Krishnan Parthasarathi <kparthas@redhat.com>
>(cherry picked from commit 4397d7e72fdff6f01c59b72eebea421f23c1a392)

Change-Id: Iace6ac0f150919cead94e6c5d99a23d28d45046e
BUG: 1226117
Signed-off-by: Avra Sengupta <asengupt@redhat.com>
Reviewed-on: http://review.gluster.org/11011
Tested-by: NetBSD Build System <jenkins@build.gluster.org>
Reviewed-by: Kaushal M <kaushal@redhat.com>

10 files changed, 78 insertions, 27 deletions

diff --git a/xlators/mgmt/glusterd/src/Makefile.am b/xlators/mgmt/glusterd/src/Makefile.am
index 74198271f48..a8f27fb5310 100644
--- a/xlators/mgmt/glusterd/src/Makefile.am
+++ b/xlators/mgmt/glusterd/src/Makefile.am
@@ -38,7 +38,7 @@ noinst_HEADERS = glusterd.h glusterd-utils.h glusterd-op-sm.h \
 	glusterd-quotad-svc.h glusterd-svc-helper.h glusterd-snapd-svc.h \
 	glusterd-snapd-svc-helper.h glusterd-rcu.h glusterd-bitd-svc.h \
 	glusterd-scrub-svc.h $(CONTRIBDIR)/userspace-rcu/rculist-extra.h \
-	glusterd-server-quorum.h
+	glusterd-server-quorum.h glusterd-errno.h
 
 AM_CPPFLAGS = $(GF_CPPFLAGS) -I$(top_srcdir)/libglusterfs/src \
 	-I$(rpclibdir) -I$(CONTRIBDIR)/rbtree \
diff --git a/xlators/mgmt/glusterd/src/glusterd-errno.h b/xlators/mgmt/glusterd/src/glusterd-errno.h
new file mode 100644
index 00000000000..435b050c7da
--- /dev/null
+++ b/xlators/mgmt/glusterd/src/glusterd-errno.h
@@ -0,0 +1,18 @@
+/*
+   Copyright (c) 2015 Red Hat, Inc. <http://www.redhat.com>
+   This file is part of GlusterFS.
+
+   This file is licensed to you under your choice of the GNU Lesser
+   General Public License, version 3 or any later version (LGPLv3 or
+   later), or the GNU General Public License, version 2 (GPLv2), in all
+   cases as published by the Free Software Foundation.
+*/
+#ifndef _GLUSTERD_ERRNO_H
+#define _GLUSTERD_ERRNO_H
+
+enum glusterd_op_errno {
+        EINTRNL   = 30800,               /* Internal Error */
+        EANOTRANS = 30801,               /* Another Transaction in Progress */
+};
+
+#endif
diff --git a/xlators/mgmt/glusterd/src/glusterd-handler.c b/xlators/mgmt/glusterd/src/glusterd-handler.c
index b297ed16443..564d78796be 100644
--- a/xlators/mgmt/glusterd/src/glusterd-handler.c
+++ b/xlators/mgmt/glusterd/src/glusterd-handler.c
@@ -633,6 +633,7 @@ glusterd_op_txn_begin (rpcsvc_request_t *req, glusterd_op_t op, void *ctx,
         uuid_t                     *txn_id          = NULL;
         glusterd_op_info_t          txn_op_info     = {{0},};
         glusterd_op_sm_event_type_t event_type      = GD_OP_EVENT_NONE;
+        uint32_t                    op_errno        = 0;
 
         GF_ASSERT (req);
         GF_ASSERT ((op > GD_OP_NONE) && (op < GD_OP_MAX));
@@ -696,7 +697,8 @@ glusterd_op_txn_begin (rpcsvc_request_t *req, glusterd_op_t op, void *ctx,
                                 goto out;
                 }
 
-                ret = glusterd_mgmt_v3_lock (volname, MY_UUID, "vol");
+                ret = glusterd_mgmt_v3_lock (volname, MY_UUID, &op_errno,
+                                             "vol");
                 if (ret) {
                         gf_log (this->name, GF_LOG_ERROR,
                                 "Unable to acquire lock for %s", volname);
diff --git a/xlators/mgmt/glusterd/src/glusterd-locks.c b/xlators/mgmt/glusterd/src/glusterd-locks.c
index c86dc8069da..0f9c2b26084 100644
--- a/xlators/mgmt/glusterd/src/glusterd-locks.c
+++ b/xlators/mgmt/glusterd/src/glusterd-locks.c
@@ -21,6 +21,7 @@
 #include "glusterd-utils.h"
 #include "glusterd-volgen.h"
 #include "glusterd-locks.h"
+#include "glusterd-errno.h"
 #include "run.h"
 #include "syscall.h"
 
@@ -191,6 +192,7 @@ out:
  * volumes */
 static int32_t
 glusterd_acquire_multiple_locks_per_entity (dict_t *dict, uuid_t uuid,
+                                            uint32_t *op_errno,
                                             int32_t count, char *type)
 {
         char           name_buf[PATH_MAX]    = "";
@@ -220,7 +222,7 @@ glusterd_acquire_multiple_locks_per_entity (dict_t *dict, uuid_t uuid,
                         break;
                 }
 
-                ret = glusterd_mgmt_v3_lock (name, uuid, type);
+                ret = glusterd_mgmt_v3_lock (name, uuid, op_errno, type);
                 if (ret) {
                         gf_log (this->name, GF_LOG_ERROR,
                                 "Failed to acquire lock for %s %s "
@@ -330,8 +332,8 @@ out:
  * if the type is "vol", this function will accordingly lock a single volume *
  * or multiple volumes */
 static int32_t
-glusterd_mgmt_v3_lock_entity (dict_t *dict, uuid_t uuid, char *type,
-                              gf_boolean_t default_value)
+glusterd_mgmt_v3_lock_entity (dict_t *dict, uuid_t uuid, uint32_t *op_errno,
+                              char *type, gf_boolean_t default_value)
 {
         char           name_buf[PATH_MAX]    = "";
         char          *name                  = NULL;
@@ -369,7 +371,7 @@ glusterd_mgmt_v3_lock_entity (dict_t *dict, uuid_t uuid, char *type,
                         goto out;
                 }
 
-                ret = glusterd_mgmt_v3_lock (name, uuid, type);
+                ret = glusterd_mgmt_v3_lock (name, uuid, op_errno, type);
                 if (ret) {
                         gf_log (this->name, GF_LOG_ERROR,
                                 "Failed to acquire lock for %s %s "
@@ -381,6 +383,7 @@ glusterd_mgmt_v3_lock_entity (dict_t *dict, uuid_t uuid, char *type,
                 /* Locking one element name after another */
                 ret = glusterd_acquire_multiple_locks_per_entity (dict,
                                                                   uuid,
+                                                                  op_errno,
                                                                   count,
                                                                   type);
                 if (ret) {
@@ -437,7 +440,7 @@ out:
 /* Try to acquire locks on multiple entities like *
  * volume, snaps etc. */
 int32_t
-glusterd_multiple_mgmt_v3_lock (dict_t *dict, uuid_t uuid)
+glusterd_multiple_mgmt_v3_lock (dict_t *dict, uuid_t uuid, uint32_t *op_errno)
 {
         int32_t        i                     = -1;
         int32_t        ret                   = -1;
@@ -456,7 +459,7 @@ glusterd_multiple_mgmt_v3_lock (dict_t *dict, uuid_t uuid)
         /* Locking one entity after other */
         for (i = 0; valid_types[i].type; i++) {
                 ret = glusterd_mgmt_v3_lock_entity
-                                            (dict, uuid,
+                                            (dict, uuid, op_errno,
                                              valid_types[i].type,
                                              valid_types[i].default_value);
                 if (ret) {
@@ -494,7 +497,8 @@ out:
 
 
 int32_t
-glusterd_mgmt_v3_lock (const char *name, uuid_t uuid, char *type)
+glusterd_mgmt_v3_lock (const char *name, uuid_t uuid, uint32_t *op_errno,
+                       char *type)
 {
         char                            key[PATH_MAX]   = "";
         int32_t                         ret             = -1;
@@ -550,6 +554,7 @@ glusterd_mgmt_v3_lock (const char *name, uuid_t uuid, char *type)
                                   "Lock for %s held by %s",
                                   name, uuid_utoa (owner));
                 ret = -1;
+                *op_errno = EANOTRANS;
                 goto out;
         }
 
diff --git a/xlators/mgmt/glusterd/src/glusterd-locks.h b/xlators/mgmt/glusterd/src/glusterd-locks.h
index b9cc8c0d1e4..de4d8fcd4d5 100644
--- a/xlators/mgmt/glusterd/src/glusterd-locks.h
+++ b/xlators/mgmt/glusterd/src/glusterd-locks.h
@@ -37,13 +37,14 @@ int32_t
 glusterd_get_mgmt_v3_lock_owner (char *volname, uuid_t *uuid);
 
 int32_t
-glusterd_mgmt_v3_lock (const char *key, uuid_t uuid, char *type);
+glusterd_mgmt_v3_lock (const char *key, uuid_t uuid, uint32_t *op_errno,
+                       char *type);
 
 int32_t
 glusterd_mgmt_v3_unlock (const char *key, uuid_t uuid, char *type);
 
 int32_t
-glusterd_multiple_mgmt_v3_lock (dict_t *dict, uuid_t uuid);
+glusterd_multiple_mgmt_v3_lock (dict_t *dict, uuid_t uuid, uint32_t *op_errno);
 
 int32_t
 glusterd_multiple_mgmt_v3_unlock (dict_t *dict, uuid_t uuid);
diff --git a/xlators/mgmt/glusterd/src/glusterd-mgmt-handler.c b/xlators/mgmt/glusterd/src/glusterd-mgmt-handler.c
index db5a19bf675..9ebaf00d32f 100644
--- a/xlators/mgmt/glusterd/src/glusterd-mgmt-handler.c
+++ b/xlators/mgmt/glusterd/src/glusterd-mgmt-handler.c
@@ -28,7 +28,8 @@ glusterd_mgmt_v3_null (rpcsvc_request_t *req)
 }
 
 static int
-glusterd_mgmt_v3_lock_send_resp (rpcsvc_request_t *req, int32_t status)
+glusterd_mgmt_v3_lock_send_resp (rpcsvc_request_t *req, int32_t status,
+                                 uint32_t op_errno)
 {
 
         gd1_mgmt_v3_lock_rsp          rsp   = {{0},};
@@ -41,7 +42,7 @@ glusterd_mgmt_v3_lock_send_resp (rpcsvc_request_t *req, int32_t status)
 
         rsp.op_ret = status;
         if (rsp.op_ret)
-                rsp.op_errno = errno;
+                rsp.op_errno = op_errno;
 
         glusterd_get_uuid (&rsp.uuid);
 
@@ -61,6 +62,7 @@ glusterd_synctasked_mgmt_v3_lock (rpcsvc_request_t *req,
 {
         int32_t                         ret         = -1;
         xlator_t                       *this        = NULL;
+        uint32_t                        op_errno    = 0;
 
         this = THIS;
         GF_ASSERT (this);
@@ -69,14 +71,14 @@ glusterd_synctasked_mgmt_v3_lock (rpcsvc_request_t *req,
         GF_ASSERT (ctx->dict);
 
         /* Trying to acquire multiple mgmt_v3 locks */
-        ret = glusterd_multiple_mgmt_v3_lock (ctx->dict, ctx->uuid);
+        ret = glusterd_multiple_mgmt_v3_lock (ctx->dict, ctx->uuid, &op_errno);
         if (ret)
                 gf_msg (this->name, GF_LOG_ERROR, 0,
                         GD_MSG_MGMTV3_LOCK_GET_FAIL,
                         "Failed to acquire mgmt_v3 locks for %s",
                          uuid_utoa (ctx->uuid));
 
-        ret = glusterd_mgmt_v3_lock_send_resp (req, ret);
+        ret = glusterd_mgmt_v3_lock_send_resp (req, ret, op_errno);
 
         gf_msg_trace (this->name, 0, "Returning %d", ret);
         return ret;
diff --git a/xlators/mgmt/glusterd/src/glusterd-mgmt.c b/xlators/mgmt/glusterd/src/glusterd-mgmt.c
index 85d8c777884..a3eaf2ebdcd 100644
--- a/xlators/mgmt/glusterd/src/glusterd-mgmt.c
+++ b/xlators/mgmt/glusterd/src/glusterd-mgmt.c
@@ -23,6 +23,7 @@
 #include "glusterd-store.h"
 #include "glusterd-snapshot-utils.h"
 #include "glusterd-messages.h"
+#include "glusterd-errno.h"
 
 extern struct rpc_clnt_program gd_mgmt_v3_prog;
 
@@ -397,7 +398,7 @@ out:
 
 int
 glusterd_mgmt_v3_initiate_lockdown (glusterd_op_t op, dict_t *dict,
-                                    char **op_errstr,
+                                    char **op_errstr, uint32_t *op_errno,
                                     gf_boolean_t  *is_acquired,
                                     uint32_t txn_generation)
 {
@@ -420,7 +421,7 @@ glusterd_mgmt_v3_initiate_lockdown (glusterd_op_t op, dict_t *dict,
         GF_ASSERT (is_acquired);
 
         /* Trying to acquire multiple mgmt_v3 locks on local node */
-        ret = glusterd_multiple_mgmt_v3_lock (dict, MY_UUID);
+        ret = glusterd_multiple_mgmt_v3_lock (dict, MY_UUID, op_errno);
         if (ret) {
                 gf_msg (this->name, GF_LOG_ERROR, 0,
                         GD_MSG_MGMTV3_LOCK_GET_FAIL,
@@ -466,6 +467,7 @@ glusterd_mgmt_v3_initiate_lockdown (glusterd_op_t op, dict_t *dict,
                 *op_errstr = gf_strdup (args.errstr);
 
         ret = args.op_ret;
+        *op_errno = args.op_errno;
 
         gf_msg_debug (this->name, 0, "Sent lock op req for %s "
                 "to %d peers. Returning %d", gd_op_list[op], peer_cnt, ret);
@@ -1701,6 +1703,7 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
         gf_boolean_t                is_acquired      = _gf_false;
         uuid_t                      *originator_uuid = NULL;
         uint32_t                    txn_generation   = 0;
+        uint32_t                    op_errno         = 0;
 
         this = THIS;
         GF_ASSERT (this);
@@ -1758,7 +1761,8 @@ glusterd_mgmt_v3_initiate_all_phases (rpcsvc_request_t *req, glusterd_op_t op,
 
         /* LOCKDOWN PHASE - Acquire mgmt_v3 locks */
         ret = glusterd_mgmt_v3_initiate_lockdown (op, dict, &op_errstr,
-                                                  &is_acquired, txn_generation);
+                                                  &op_errno, &is_acquired,
+                                                  txn_generation);
         if (ret) {
                 gf_msg (this->name, GF_LOG_ERROR, 0,
                         GD_MSG_MGMTV3_LOCKDOWN_FAIL,
@@ -1828,8 +1832,12 @@ out:
                 }
         }
 
+        if (ret && (op_errno == 0))
+                op_errno = EINTRNL;
+
         /* SEND CLI RESPONSE */
-        glusterd_op_send_cli_response (op, op_ret, 0, req, dict, op_errstr);
+        glusterd_op_send_cli_response (op, op_ret, op_errno, req,
+                                       dict, op_errstr);
 
         if (req_dict)
                 dict_unref (req_dict);
@@ -1929,6 +1937,7 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
         gf_boolean_t                success          = _gf_false;
         char                        *cli_errstr      = NULL;
         uint32_t                    txn_generation   = 0;
+        uint32_t                    op_errno         = 0;
 
         this = THIS;
         GF_ASSERT (this);
@@ -1986,7 +1995,8 @@ glusterd_mgmt_v3_initiate_snap_phases (rpcsvc_request_t *req, glusterd_op_t op,
 
         /* LOCKDOWN PHASE - Acquire mgmt_v3 locks */
         ret = glusterd_mgmt_v3_initiate_lockdown (op, dict, &op_errstr,
-                                                  &is_acquired, txn_generation);
+                                                  &op_errno, &is_acquired,
+                                                  txn_generation);
         if (ret) {
                 gf_msg (this->name, GF_LOG_ERROR, 0,
                         GD_MSG_MGMTV3_LOCKDOWN_FAIL,
@@ -2161,8 +2171,12 @@ out:
                 }
         }
 
+        if (ret && (op_errno == 0))
+                op_errno = EINTRNL;
+
         /* SEND CLI RESPONSE */
-        glusterd_op_send_cli_response (op, op_ret, 0, req, dict, op_errstr);
+        glusterd_op_send_cli_response (op, op_ret, op_errno, req,
+                                       dict, op_errstr);
 
         if (req_dict)
                 dict_unref (req_dict);
diff --git a/xlators/mgmt/glusterd/src/glusterd-op-sm.c b/xlators/mgmt/glusterd/src/glusterd-op-sm.c
index 5a23d2bf0c7..326968ea6b8 100644
--- a/xlators/mgmt/glusterd/src/glusterd-op-sm.c
+++ b/xlators/mgmt/glusterd/src/glusterd-op-sm.c
@@ -3210,6 +3210,7 @@ glusterd_op_ac_lock (glusterd_op_sm_event_t *event, void *ctx)
         glusterd_op_lock_ctx_t         *lock_ctx        = NULL;
         glusterd_conf_t                *priv            = NULL;
         xlator_t                       *this            = NULL;
+        uint32_t                        op_errno        = 0;
 
         GF_ASSERT (event);
         GF_ASSERT (ctx);
@@ -3232,7 +3233,7 @@ glusterd_op_ac_lock (glusterd_op_sm_event_t *event, void *ctx)
                                 "Unable to acquire volname");
                 else {
                         ret = glusterd_mgmt_v3_lock (volname, lock_ctx->uuid,
-                                                     "vol");
+                                                     &op_errno, "vol");
                         if (ret)
                                 gf_log (this->name, GF_LOG_ERROR,
                                         "Unable to acquire lock for %s",
@@ -3242,7 +3243,7 @@ glusterd_op_ac_lock (glusterd_op_sm_event_t *event, void *ctx)
                 ret = dict_get_str (lock_ctx->dict, "globalname", &globalname);
                 if (!ret) {
                         ret = glusterd_mgmt_v3_lock (globalname, lock_ctx->uuid,
-                                                     "global");
+                                                     &op_errno, "global");
                         if (ret)
                                 gf_log (this->name, GF_LOG_ERROR,
                                         "Unable to acquire lock for %s",
diff --git a/xlators/mgmt/glusterd/src/glusterd-rpc-ops.c b/xlators/mgmt/glusterd/src/glusterd-rpc-ops.c
index 231c2f720ba..415d04f96f1 100644
--- a/xlators/mgmt/glusterd/src/glusterd-rpc-ops.c
+++ b/xlators/mgmt/glusterd/src/glusterd-rpc-ops.c
@@ -165,7 +165,8 @@ glusterd_op_send_cli_response (glusterd_op_t op, int32_t op_ret,
         }
 
         rsp.op_ret = op_ret;
-        rsp.op_errno = errno;
+        rsp.op_errno = op_errno;
+
         if (errstr)
                 rsp.op_errstr = errstr;
         else if (op_errstr)
diff --git a/xlators/mgmt/glusterd/src/glusterd-syncop.c b/xlators/mgmt/glusterd/src/glusterd-syncop.c
index 6f36478aeca..2ac947fd710 100644
--- a/xlators/mgmt/glusterd/src/glusterd-syncop.c
+++ b/xlators/mgmt/glusterd/src/glusterd-syncop.c
@@ -1692,6 +1692,7 @@ gd_sync_task_begin (dict_t *op_ctx, rpcsvc_request_t * req)
         gf_boolean_t                is_global        = _gf_false;
         uuid_t                      *txn_id          = NULL;
         glusterd_op_info_t          txn_opinfo       = {{0},};
+        uint32_t                    op_errno         = 0;
 
         this = THIS;
         GF_ASSERT (this);
@@ -1768,7 +1769,8 @@ gd_sync_task_begin (dict_t *op_ctx, rpcsvc_request_t * req)
                                 goto out;
                 }
 
-                ret = glusterd_mgmt_v3_lock (volname, MY_UUID, "vol");
+                ret = glusterd_mgmt_v3_lock (volname, MY_UUID,
+                                             &op_errno, "vol");
                 if (ret) {
                         gf_log (this->name, GF_LOG_ERROR,
                                 "Unable to acquire lock for %s", volname);
@@ -1782,7 +1784,8 @@ gd_sync_task_begin (dict_t *op_ctx, rpcsvc_request_t * req)
 
 global:
         if (is_global) {
-                ret = glusterd_mgmt_v3_lock (global, MY_UUID, "global");
+                ret = glusterd_mgmt_v3_lock (global, MY_UUID, &op_errno,
+                                             "global");
                 if (ret) {
                         gf_log (this->name, GF_LOG_ERROR,
                                 "Unable to acquire lock for %s", global);
@@ -1856,7 +1859,11 @@ out:
                                 uuid_utoa (*txn_id));
         }
 
-        glusterd_op_send_cli_response (op, op_ret, 0, req, op_ctx, op_errstr);
+        if (ret && (op_errno == 0))
+                op_errno = -1;
+
+        glusterd_op_send_cli_response (op, op_ret, op_errno, req,
+                                       op_ctx, op_errstr);
 
         if (volname)
                 GF_FREE (volname);