dht: utilize the framework to pass-through xlator tasks

Also fixes the issue caused due to not converting back the fn function
to after getting its address. We wanted the value of the field, not
the address of the pt_fop field.

With this patch, DHT will always be started in pass-through
mode if the number of subvols is just 1.

Fixes some tests to make sure DHT is in full config (ie, subvols > 1).
  - increased timeout of brick-mux test as it was bordering on 300 seconds.
  - Also change the volume type to supported 'replica 3' from 'replica 2'.
  - also no DHT tests should assume presence of DHT when there is
    just 1 brick in volume

Credits: Nithya B <nbalacha@redhat.com>

fixes: #405
Change-Id: I8e55239ce58d6ac6ae1901e2e384be1ecbd33d6e
Signed-off-by: Amar Tumballi <amarts@redhat.com>

1 files changed, 51 insertions, 7 deletions

diff --git a/xlators/cluster/dht/src/dht.c b/xlators/cluster/dht/src/dht.c
index 677905f236e..6dfaa3b23ed 100644
--- a/xlators/cluster/dht/src/dht.c
+++ b/xlators/cluster/dht/src/dht.c
@@ -11,10 +11,32 @@
 #include "statedump.h"
 #include "dht-common.h"
 
-class_methods_t class_methods = {.init = dht_init,
-                                 .fini = dht_fini,
-                                 .reconfigure = dht_reconfigure,
-                                 .notify = dht_notify};
+struct xlator_fops dht_pt_fops = {
+    /* we need to keep mkdir to make sure we
+       have layout on new directory */
+    .mkdir = dht_pt_mkdir,
+    .getxattr = dht_pt_getxattr,
+    .fgetxattr = dht_pt_fgetxattr,
+
+    /* required to trace fop properly in changelog */
+    .rename = dht_pt_rename,
+
+    /* FIXME: commenting the '.lookup()' below made some of
+       the failing tests to pass. I would remove the below
+       line, but keeping it here as a reminder for people
+       to check for issues if they find concerns with DHT
+       pass-through logic  */
+    /*
+      .lookup = dht_lookup,
+      .readdir = dht_readdir,
+      .readdirp = dht_readdirp,
+    */
+    /* Keeping above as commented, mainly to support the
+       usecase of a gluster volume getting to 1x(anytype),
+       due to remove-brick (shrinking) exercise. In that case,
+       we would need above fops to be available, so we can
+       handle the case of dangling linkto files (if any) */
+};
 
 struct xlator_fops fops = {
     .ipc = dht_ipc,
@@ -74,6 +96,28 @@ struct xlator_dumpops dumpops = {
     .inodectx = dht_inodectx_dump,
 };
 
-struct xlator_cbks cbks = {.release = dht_release,
-                           //      .releasedir = dht_releasedir,
-                           .forget = dht_forget};
+struct xlator_cbks cbks = {
+    .release = dht_release,
+    //      .releasedir = dht_releasedir,
+    .forget = dht_forget,
+};
+
+extern int32_t
+mem_acct_init(xlator_t *this);
+extern struct volume_options options[];
+
+xlator_api_t xlator_api = {
+    .init = dht_init,
+    .fini = dht_fini,
+    .notify = dht_notify,
+    .reconfigure = dht_reconfigure,
+    .mem_acct_init = mem_acct_init,
+    .op_version = {1}, /* Present from the initial version */
+    .dumpops = &dumpops,
+    .fops = &fops,
+    .cbks = &cbks,
+    .options = options,
+    .identifier = "distribute",
+    .pass_through_fops = &dht_pt_fops,
+    .category = GF_MAINTAINED,
+};