cluster/ec: Node uuid xattr support update for EC

Problem:
The change in EC to return list of node uuids for
GF_XATTR_NODE_UUID_KEY was causing problems with
geo-rep.

Fix:
This patch will allow to get the single node uuid
as it was doing before with the key
"GF_XATTR_NODE_UUID_KEY", and will also allow to get
the list of node uuids by using a new key
"GF_XATTR_LIST_NODE_UUIDS_KEY". This will solve
the problem with geo-rep and any other features which
were depending on this.

>BUG: 1462790
>Change-Id: I2d9214a9658d4a41a3d6de08600884d2bda5f3eb
>Signed-off-by: Sunil Kumar Acharya <sheggodu@redhat.com>
>Reviewed-on: https://review.gluster.org/17594
>Smoke: Gluster Build System <jenkins@build.gluster.org>
>Reviewed-by: Xavier Hernandez <xhernandez@datalab.es>
>Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
>CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
>Signed-off-by: Sunil Kumar Acharya <sheggodu@redhat.com>

BUG: 1487647
Change-Id: I2d9214a9658d4a41a3d6de08600884d2bda5f3eb
Signed-off-by: Sunil Kumar Acharya <sheggodu@redhat.com>
Reviewed-on: https://review.gluster.org/17667
Smoke: Gluster Build System <jenkins@build.gluster.org>
Reviewed-by: Xavier Hernandez <xhernandez@datalab.es>
NetBSD-regression: NetBSD Build System <jenkins@build.gluster.org>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>

3 files changed, 25 insertions, 6 deletions

diff --git a/libglusterfs/src/glusterfs.h b/libglusterfs/src/glusterfs.h
index 7bb5d1f8c24..0a3891b5f8b 100644
--- a/libglusterfs/src/glusterfs.h
+++ b/libglusterfs/src/glusterfs.h
@@ -106,6 +106,8 @@
                                          strlen (x)) == 0))
 #define XATTR_IS_NODE_UUID(x) (strncmp (x, GF_XATTR_NODE_UUID_KEY,      \
                                         strlen (GF_XATTR_NODE_UUID_KEY)) == 0)
+#define XATTR_IS_NODE_UUID_LIST(x) (strncmp (x, GF_XATTR_LIST_NODE_UUIDS_KEY, \
+                                    strlen (GF_XATTR_LIST_NODE_UUIDS_KEY)) == 0)
 #define XATTR_IS_LOCKINFO(x) (strncmp (x, GF_XATTR_LOCKINFO_KEY,        \
                                        strlen (GF_XATTR_LOCKINFO_KEY)) == 0)
 
diff --git a/xlators/cluster/ec/src/ec-combine.c b/xlators/cluster/ec/src/ec-combine.c
index e09381b9f8a..4d0cc076680 100644
--- a/xlators/cluster/ec/src/ec-combine.c
+++ b/xlators/cluster/ec/src/ec-combine.c
@@ -351,7 +351,8 @@ out:
 
 static int32_t
 ec_dict_data_concat(const char *fmt, ec_cbk_data_t *cbk, int32_t which,
-                    char *key, const char *def, gf_boolean_t global, ...)
+                    char *key, char *new_key, const char *def,
+                    gf_boolean_t global, ...)
 {
     ec_t *ec = cbk->fop->xl->private;
     data_t *data[ec->nodes];
@@ -432,6 +433,9 @@ ec_dict_data_concat(const char *fmt, ec_cbk_data_t *cbk, int32_t which,
     memcpy(str + len, post, postlen + 1);
 
     dict = (which == EC_COMBINE_XDATA) ? cbk->xdata : cbk->dict;
+    if (new_key) {
+        key = new_key;
+    }
     err = dict_set_dynstr(dict, key, str);
     if (err != 0) {
         goto out;
@@ -677,14 +681,14 @@ int32_t ec_dict_data_combine(dict_t * dict, char * key, data_t * value,
         (strcmp(key, GF_XATTR_USER_PATHINFO_KEY) == 0))
     {
         return ec_dict_data_concat("(<EC:%s> { })", data->cbk, data->which,
-                                   key, NULL, _gf_false,
+                                   key, NULL, NULL, _gf_false,
                                    data->cbk->fop->xl->name);
     }
 
     if (strncmp(key, GF_XATTR_CLRLK_CMD, strlen(GF_XATTR_CLRLK_CMD)) == 0)
     {
         return ec_dict_data_concat("{\n}", data->cbk, data->which, key, NULL,
-                                   _gf_false);
+                                   NULL, _gf_false);
     }
 
     if (strncmp(key, GF_XATTR_LOCKINFO_KEY,
@@ -715,8 +719,14 @@ int32_t ec_dict_data_combine(dict_t * dict, char * key, data_t * value,
     }
 
     if (XATTR_IS_NODE_UUID(key)) {
-        return ec_dict_data_concat("{ }", data->cbk, data->which, key,
-                                   UUID0_STR, _gf_true);
+        if (data->cbk->fop->int32) {
+                /* List of node uuid is requested */
+                return ec_dict_data_concat("{ }", data->cbk, data->which, key,
+                                           GF_XATTR_LIST_NODE_UUIDS_KEY,
+                                           UUID0_STR, _gf_true);
+        } else {
+                return ec_dict_data_uuid(data->cbk, data->which, key);
+        }
     }
 
     if (fnmatch(GF_XATTR_STIME_PATTERN, key, FNM_NOESCAPE) == 0)
diff --git a/xlators/cluster/ec/src/ec-inode-read.c b/xlators/cluster/ec/src/ec-inode-read.c
index dbbbb10033a..d925e82ba36 100644
--- a/xlators/cluster/ec/src/ec-inode-read.c
+++ b/xlators/cluster/ec/src/ec-inode-read.c
@@ -487,7 +487,14 @@ ec_getxattr (call_frame_t *frame, xlator_t *this, uintptr_t target,
         }
     }
     if (name != NULL) {
-        fop->str[0] = gf_strdup(name);
+        /* In case of list-node-uuids xattr, set flag to indicate
+         * the same and use node-uuid xattr for winding fop */
+        if (XATTR_IS_NODE_UUID_LIST(name)) {
+                fop->int32 = 1;
+                fop->str[0] = gf_strdup(GF_XATTR_NODE_UUID_KEY);
+        } else {
+                fop->str[0] = gf_strdup(name);
+        }
         if (fop->str[0] == NULL) {
             gf_msg (this->name, GF_LOG_ERROR, ENOMEM,
                     EC_MSG_NO_MEMORY,