features/marker-quota: more stringent error handling in rename.

If an error occurs and op_errno is not set to non-zero value, we can
end up in loosing a frame resulting in a hung syscall. This patch
adds code setting op_errno appropriately in storage/posix and
makes marker to set err to a default non-zero value in case of
op_errno being zero.

Change-Id: Idc2c3e843b932709a69b32ba67deb284547168f2
BUG: 833586
Signed-off-by: Raghavendra G <raghavendra@gluster.com>
Reviewed-on: http://review.gluster.org/6913
Tested-by: Gluster Build System <jenkins@build.gluster.com>
Reviewed-by: Niels de Vos <ndevos@redhat.com>

2 files changed, 19 insertions, 11 deletions

diff --git a/xlators/features/marker/src/marker.c b/xlators/features/marker/src/marker.c
index d6b6dd358de..45058652bca 100644
--- a/xlators/features/marker/src/marker.c
+++ b/xlators/features/marker/src/marker.c
@@ -1021,7 +1021,7 @@ marker_rename_done (call_frame_t *frame, void *cookie, xlator_t *this,
 
         if (op_ret < 0) {
                 if (local->err == 0) {
-                        local->err = op_errno;
+                        local->err =  op_errno ? op_errno : EINVAL;
                 }
 
                 gf_log (this->name, GF_LOG_WARNING,
@@ -1037,6 +1037,11 @@ marker_rename_done (call_frame_t *frame, void *cookie, xlator_t *this,
         } else if (local->err != 0) {
                 STACK_UNWIND_STRICT (rename, frame, -1, local->err, NULL, NULL,
                                      NULL, NULL, NULL, NULL);
+        } else {
+                gf_log (this->name, GF_LOG_CRITICAL,
+                        "continuation stub to unwind the call is absent, hence "
+                        "call will be hung (call-stack id = %"PRIu64")",
+                        frame->root->unique);
         }
 
         mq_reduce_parent_size (this, &oplocal->loc, oplocal->contribution);
@@ -1082,7 +1087,7 @@ marker_rename_release_newp_lock (call_frame_t *frame, void *cookie,
 
         if (op_ret < 0) {
                 if (local->err == 0) {
-                        local->err = op_errno;
+                        local->err = op_errno ? op_errno : EINVAL;
                 }
 
                 gf_log (this->name, GF_LOG_WARNING,
@@ -1271,7 +1276,7 @@ marker_do_rename (call_frame_t *frame, void *cookie, xlator_t *this,
                 MARKER_RESET_UID_GID (frame, frame->root, local);
 
         if ((op_ret < 0) && (op_errno != ENOATTR)) {
-                local->err = op_errno;
+                local->err = op_errno ? op_errno : EINVAL;
                 gf_log (this->name, GF_LOG_WARNING,
                         "fetching contribution values from %s (gfid:%s) "
                         "failed (%s)", local->loc.path,
@@ -1283,7 +1288,7 @@ marker_do_rename (call_frame_t *frame, void *cookie, xlator_t *this,
         if (local->loc.inode != NULL) {
                 GET_CONTRI_KEY (contri_key, local->loc.parent->gfid, ret);
                 if (ret < 0) {
-                        local->err = errno;
+                        local->err = errno ? errno : ENOMEM;
                         goto err;
                 }
 
@@ -1323,7 +1328,7 @@ marker_get_newpath_contribution (call_frame_t *frame, void *cookie,
                 MARKER_RESET_UID_GID (frame, frame->root, local);
 
         if ((op_ret < 0) && (op_errno != ENOATTR)) {
-                local->err = op_errno;
+                local->err = op_errno ? op_errno : EINVAL;
                 gf_log (this->name, GF_LOG_WARNING,
                         "fetching contribution values from %s (gfid:%s) "
                         "failed (%s)", oplocal->loc.path,
@@ -1334,7 +1339,7 @@ marker_get_newpath_contribution (call_frame_t *frame, void *cookie,
 
         GET_CONTRI_KEY (contri_key, oplocal->loc.parent->gfid, ret);
         if (ret < 0) {
-                local->err = errno;
+                local->err = errno ? errno : ENOMEM;
                 goto err;
         }
 
@@ -1344,7 +1349,7 @@ marker_get_newpath_contribution (call_frame_t *frame, void *cookie,
         if (local->loc.inode != NULL) {
                 GET_CONTRI_KEY (contri_key, local->loc.parent->gfid, ret);
                 if (ret < 0) {
-                        local->err = errno;
+                        local->err = errno ? errno : ENOMEM;
                         goto err;
                 }
 
@@ -1385,7 +1390,7 @@ marker_get_oldpath_contribution (call_frame_t *frame, void *cookie,
         oplocal = local->oplocal;
 
         if (op_ret < 0) {
-                local->err = op_errno;
+                local->err = op_errno ? op_errno : EINVAL;
                 gf_log (this->name, GF_LOG_WARNING,
                         "cannot hold inodelk on %s (gfid:%s) (%s)",
                         local->next_lock_on->path,
@@ -1396,7 +1401,7 @@ marker_get_oldpath_contribution (call_frame_t *frame, void *cookie,
 
         GET_CONTRI_KEY (contri_key, oplocal->loc.parent->gfid, ret);
         if (ret < 0) {
-                local->err = errno;
+                local->err = errno ? errno : ENOMEM;
                 goto quota_err;
         }
 
@@ -1452,7 +1457,7 @@ marker_rename_inodelk_cbk (call_frame_t *frame, void *cookie, xlator_t *this,
                         loc = &local->parent_loc;
                 }
 
-                local->err = op_errno;
+                local->err = op_errno ? op_errno : EINVAL;
                 gf_log (this->name, GF_LOG_WARNING,
                         "cannot hold inodelk on %s (gfid:%s) (%s)",
                         loc->path, uuid_utoa (loc->inode->gfid),
diff --git a/xlators/storage/posix/src/posix.c b/xlators/storage/posix/src/posix.c
index 6a7e691724e..71daa3e3761 100644
--- a/xlators/storage/posix/src/posix.c
+++ b/xlators/storage/posix/src/posix.c
@@ -3393,7 +3393,7 @@ posix_getxattr (call_frame_t *frame, xlator_t *this,
 
         dict = dict_new ();
         if (!dict) {
-		op_errno = ENOMEM;
+                op_errno = ENOMEM;
                 goto out;
         }
 
@@ -3562,6 +3562,7 @@ posix_getxattr (call_frame_t *frame, xlator_t *this,
                 value = GF_CALLOC (size + 1, sizeof(char), gf_posix_mt_char);
                 if (!value) {
                         op_ret = -1;
+                        op_errno = ENOMEM;
                         goto out;
                 }
                 size = sys_lgetxattr (real_path, key, value, size);
@@ -3577,6 +3578,7 @@ posix_getxattr (call_frame_t *frame, xlator_t *this,
                 value [size] = '\0';
                 op_ret = dict_set_dynptr (dict, key, value, size);
                 if (op_ret < 0) {
+                        op_errno = -op_ret;
                         gf_log (this->name, GF_LOG_ERROR, "dict set operation "
                                 "on %s for the key %s failed.", real_path, key);
                         GF_FREE (value);
@@ -3656,6 +3658,7 @@ posix_getxattr (call_frame_t *frame, xlator_t *this,
                 value [size] = '\0';
                 op_ret = dict_set_dynptr (dict, key, value, size);
                 if (op_ret < 0) {
+                        op_errno = -op_ret;
                         gf_log (this->name, GF_LOG_ERROR, "dict set operation "
                                 "on %s for the key %s failed.", real_path, key);
                         GF_FREE (value);