cluster/afr: Heal directory rename without rmdir/mkdir

Problem1:
When a directory is renamed while a brick
is down entry-heal always did an rm -rf on that directory on
the sink on old location and did mkdir and created the directory
hierarchy again in the new location. This is inefficient.

Problem2:
Renamedir heal order may lead to a scenario where directory in
the new location could be created before deleting it from old
location leading to 2 directories with same gfid in posix.

Fix:
As part of heal, if oldlocation is healed first and is not present in
source-brick always rename it into a hidden directory inside the
sink-brick so that when heal is triggered in new-location shd can
rename it from this hidden directory to the new-location.

If new-location heal is triggered first and it detects that the
directory already exists in the brick, then it should skip healing the
directory until it appears in the hidden directory.

Credits: Ravi for rename-data-loss.t script

Fixes: #1211
Change-Id: I0cba2006f35cd03d314d18211ce0bd530e254843
Signed-off-by: Pranith Kumar K <pkarampu@redhat.com>

1 files changed, 41 insertions, 5 deletions

diff --git a/xlators/cluster/afr/src/afr-common.c b/xlators/cluster/afr/src/afr-common.c
index 4c8fa31b679..1a4341a66d9 100644
--- a/xlators/cluster/afr/src/afr-common.c
+++ b/xlators/cluster/afr/src/afr-common.c
@@ -45,6 +45,41 @@ afr_quorum_errno(afr_private_t *priv)
     return ENOTCONN;
 }
 
+gf_boolean_t
+afr_is_private_directory(afr_private_t *priv, uuid_t pargfid, const char *name,
+                         pid_t pid)
+{
+    if (!__is_root_gfid(pargfid)) {
+        return _gf_false;
+    }
+
+    if (strcmp(name, GF_REPLICATE_TRASH_DIR) == 0) {
+        /*For backward compatibility /.landfill is private*/
+        return _gf_true;
+    }
+
+    if (pid == GF_CLIENT_PID_GSYNCD) {
+        /*geo-rep needs to create/sync private directory on slave because
+         * it appears in changelog*/
+        return _gf_false;
+    }
+
+    if (pid == GF_CLIENT_PID_GLFS_HEAL || pid == GF_CLIENT_PID_SELF_HEALD) {
+        if (strcmp(name, priv->anon_inode_name) == 0) {
+            /* anonymous-inode dir is private*/
+            return _gf_true;
+        }
+    } else {
+        if (strncmp(name, AFR_ANON_DIR_PREFIX, strlen(AFR_ANON_DIR_PREFIX)) ==
+            0) {
+            /* anonymous-inode dir prefix is private for geo-rep to work*/
+            return _gf_true;
+        }
+    }
+
+    return _gf_false;
+}
+
 void
 afr_fill_success_replies(afr_local_t *local, afr_private_t *priv,
                          unsigned char *replies)
@@ -3978,11 +4013,10 @@ afr_lookup(call_frame_t *frame, xlator_t *this, loc_t *loc, dict_t *xattr_req)
         return 0;
     }
 
-    if (__is_root_gfid(loc->parent->gfid)) {
-        if (!strcmp(loc->name, GF_REPLICATE_TRASH_DIR)) {
-            op_errno = EPERM;
-            goto out;
-        }
+    if (afr_is_private_directory(this->private, loc->parent->gfid, loc->name,
+                                 frame->root->pid)) {
+        op_errno = EPERM;
+        goto out;
     }
 
     local = AFR_FRAME_INIT(frame, op_errno);
@@ -5660,6 +5694,7 @@ afr_priv_dump(xlator_t *this)
                        priv->background_self_heal_count);
     gf_proc_dump_write("healers", "%d", priv->healers);
     gf_proc_dump_write("read-hash-mode", "%d", priv->hash_mode);
+    gf_proc_dump_write("use-anonymous-inode", "%d", priv->use_anon_inode);
     if (priv->quorum_count == AFR_QUORUM_AUTO) {
         gf_proc_dump_write("quorum-type", "auto");
     } else if (priv->quorum_count == 0) {
@@ -6653,6 +6688,7 @@ afr_priv_destroy(afr_private_t *priv)
     GF_FREE(priv->local);
     GF_FREE(priv->pending_key);
     GF_FREE(priv->children);
+    GF_FREE(priv->anon_inode);
     GF_FREE(priv->child_up);
     GF_FREE(priv->halo_child_up);
     GF_FREE(priv->child_latency);