cluster/afr: GFID split-brain resolution with existing CLI

Problem:
Currently there is no way for the admin from CLI to resolve gfid
split-brain based on some policy like choice of the brick, mtime
or size.

Fix:
With the existing CLI options based on size, mtime, and choice of
brick, we do lookup on the parent for the specified file. As
part of the lookup, if we find gfid mismatch, we resolve them
based on the policy and return. If the file is not in gfid split-
brain, then we check for the data and metadata split-brain in the
getxattr code path, and resolve if any.

This will work provided absolute path to the file with the CLI
and not with gfid of the file. Hence the source-brick policy
without any file path will also not resolve the gfid split-brain
since it uses the gfid of the files. But it can resolve any other
type of split-brains and skip the gfid mismatch resolution with
the usual error message.

Reverting the change https://review.gluster.org/17290. This patch
resolves the issue.

Fixes gluster/glusterfs#135

Change-Id: Iaeba6fc32f184a34255d03be87cda02773130a09
BUG: 1459530
Signed-off-by: karthik-us <ksubrahm@redhat.com>
Reviewed-on: https://review.gluster.org/17485
Reviewed-by: Ravishankar N <ravishankar@redhat.com>
Reviewed-by: Pranith Kumar Karampuri <pkarampu@redhat.com>
CentOS-regression: Gluster Build System <jenkins@build.gluster.org>
Smoke: Gluster Build System <jenkins@build.gluster.org>

1 files changed, 7 insertions, 100 deletions

diff --git a/xlators/cluster/afr/src/afr-self-heal-entry.c b/xlators/cluster/afr/src/afr-self-heal-entry.c
index 82ae6432d7d..d7e9e60a7bf 100644
--- a/xlators/cluster/afr/src/afr-self-heal-entry.c
+++ b/xlators/cluster/afr/src/afr-self-heal-entry.c
@@ -17,105 +17,6 @@
 #include "syncop-utils.h"
 #include "events.h"
 
-int
-afr_selfheal_gfid_mismatch_by_majority (struct afr_reply *replies,
-                                        int child_count)
-{
-        int             j                  = 0;
-        int             i                  = 0;
-        int             src                = -1;
-        int             votes[child_count];
-
-        for (i = 0; i < child_count; i++) {
-                if (!replies[i].valid || replies[i].op_ret == -1)
-                        continue;
-
-                votes[i] = 1;
-                for (j = i+1; j < child_count; j++) {
-                        if ((!gf_uuid_compare (replies[i].poststat.ia_gfid,
-                            replies[j].poststat.ia_gfid)))
-                                votes[i]++;
-                        if (votes[i] > child_count / 2) {
-                                src = i;
-                                goto out;
-                        }
-                }
-        }
-
-out:
-        return src;
-}
-
-int
-afr_gfid_split_brain_source (xlator_t *this, struct afr_reply *replies,
-                             inode_t *inode, uuid_t pargfid, char *bname,
-                             int src_idx, int child_idx,
-                             unsigned char *locked_on, int *src)
-{
-        afr_private_t   *priv     = NULL;
-        char             g1[64]   = {0,};
-        char             g2[64]   = {0,};
-        int              up_count = 0;
-
-        priv = this->private;
-        up_count = AFR_COUNT (locked_on, priv->child_count);
-        if (up_count != priv->child_count) {
-                gf_msg (this->name, GF_LOG_ERROR, 0,
-                        AFR_MSG_SPLIT_BRAIN,
-                        "All the bricks should be up to resolve the gfid split "
-                        "brain");
-                goto out;
-        }
-        switch (priv->fav_child_policy) {
-        case AFR_FAV_CHILD_BY_SIZE:
-                *src = afr_sh_fav_by_size (this, replies, inode);
-                break;
-        case AFR_FAV_CHILD_BY_MTIME:
-                *src = afr_sh_fav_by_mtime (this, replies, inode);
-                break;
-        case AFR_FAV_CHILD_BY_CTIME:
-                *src = afr_sh_fav_by_ctime(this, replies, inode);
-                break;
-        case AFR_FAV_CHILD_BY_MAJORITY:
-                if (priv->child_count != 2)
-                        *src = afr_selfheal_gfid_mismatch_by_majority (replies,
-                                                                       priv->child_count);
-                else
-                        *src = -1;
-
-                if (*src == -1) {
-                        gf_msg (this->name, GF_LOG_ERROR, 0,
-                                AFR_MSG_SPLIT_BRAIN, "No majority to resolve "
-                                "gfid split brain");
-                }
-                break;
-        default:
-                break;
-        }
-
-out:
-        if (*src == -1) {
-                gf_msg (this->name, GF_LOG_ERROR, 0, AFR_MSG_SPLIT_BRAIN,
-                        "Gfid mismatch detected for <gfid:%s>/%s>, %s on %s and"
-                        " %s on %s. Skipping conservative merge on the file.",
-                        uuid_utoa (pargfid), bname,
-                        uuid_utoa_r (replies[child_idx].poststat.ia_gfid, g1),
-                        priv->children[child_idx]->name,
-                        uuid_utoa_r (replies[src_idx].poststat.ia_gfid, g2),
-                        priv->children[src_idx]->name);
-                gf_event (EVENT_AFR_SPLIT_BRAIN, "subvol=%s;type=gfid;file="
-                          "<gfid:%s>/%s>;count=2;child-%d=%s;gfid-%d=%s;"
-                          "child-%d=%s;gfid-%d=%s", this->name,
-                          uuid_utoa (pargfid), bname, child_idx,
-                          priv->children[child_idx]->name, child_idx,
-                          uuid_utoa_r (replies[child_idx].poststat.ia_gfid, g1),
-                          src_idx, priv->children[src_idx]->name, src_idx,
-                          uuid_utoa_r (replies[src_idx].poststat.ia_gfid, g2));
-                return -1;
-        }
-        return 0;
-}
-
 static int
 afr_selfheal_entry_delete (xlator_t *this, inode_t *dir, const char *name,
                            inode_t *inode, int child, struct afr_reply *replies)
@@ -332,7 +233,13 @@ afr_selfheal_detect_gfid_and_type_mismatch (xlator_t *this,
                         ret = afr_gfid_split_brain_source (this, replies, inode,
                                                            pargfid, bname,
                                                            src_idx, i,
-                                                           locked_on, src);
+                                                           locked_on, src,
+                                                           NULL);
+                        if (ret)
+                                gf_msg (this->name, GF_LOG_ERROR, 0,
+                                        AFR_MSG_SPLIT_BRAIN,
+                                        "Skipping conservative merge on the "
+                                        "file.");
                         return ret;
                 }