From eff25494501810de50cfefa414403f7fdbf8fb25 Mon Sep 17 00:00:00 2001

From: Mohammed Rafi KC <rkavunga@redhat.com>

Date: Mon, 3 Jul 2017 12:45:38 +0530

Subject: [PATCH 555/557] svc: send revalidate lookup on special dir

.snaps directory is a virtual direcotory, that doesn't

exist on the backend. Even though it is a special dentry,

it doesn't have a dedicated inode. So the inode number is

always random. Which means it will get different inode

number when reboot happens on snapd process.

Now with windows client the show-direcotry feature requires

a lookup on the .snpas direcoty post readdirp on root.

If the snapd restarted after a lookup, then subsequent lookup

will fail, because linked inode will be stale.

This patch will do a revalidate lookup with a new inode.

Back port of>

>Change-Id: If97c07ecb307cefe7c86be8ebd05e28cbf678d1f

>BUG: 1467513

>Signed-off-by: Mohammed Rafi KC <rkavunga@redhat.com>

>Reviewed-on: https://review.gluster.org/17690

>CentOS-regression: Gluster Build System <jenkins@build.gluster.org>

>Reviewed-by: Raghavendra Bhat <raghavendra@redhat.com>

>Smoke: Gluster Build System <jenkins@build.gluster.org>

Change-Id: If97c07ecb307cefe7c86be8ebd05e28cbf678d1f

BUG: 1191480

Signed-off-by: Mohammed Rafi KC <rkavunga@redhat.com>

Reviewed-on: https://code.engineering.redhat.com/gerrit/111807

Reviewed-by: Atin Mukherjee <amukherj@redhat.com>

---

 .../features/snapview-client/src/snapview-client.c | 77 ++++++++++++++++++++++

 .../features/snapview-client/src/snapview-client.h |  4 ++

 2 files changed, 81 insertions(+)

diff --git a/xlators/features/snapview-client/src/snapview-client.c b/xlators/features/snapview-client/src/snapview-client.c

index 6eb7cc0..efc3362 100644

--- a/xlators/features/snapview-client/src/snapview-client.c

+++ b/xlators/features/snapview-client/src/snapview-client.c

@@ -1666,6 +1666,14 @@ gf_svc_readdirp_lookup_cbk (call_frame_t *frame, void *cookie, xlator_t *this,

                 dict_unref (xdata);

         if (op_ret) {

+                if (op_errno == ESTALE && !local->revalidate) {

+                        local->revalidate = 1;

+                        ret = gf_svc_special_dir_revalidate_lookup (frame,

+                                                                    this);

+

+                        if (!ret)

+                                return 0;

+                }

                 op_ret = 0;

                 op_errno = ENOENT;

                 goto out;

@@ -1715,6 +1723,75 @@ out:

         return 0;

 }

+int

+gf_svc_special_dir_revalidate_lookup (call_frame_t *frame, xlator_t *this)

+{

+        svc_private_t *private    = NULL;

+        svc_local_t   *local      = NULL;

+        loc_t         *loc        = NULL;

+        dict_t        *tmp_xdata  = NULL;

+        char          *path       = NULL;

+        int            ret        = -1;

+

+        GF_VALIDATE_OR_GOTO ("snapview-client", this, out);

+        GF_VALIDATE_OR_GOTO (this->name, this->private, out);

+

+        private = this->private;

+

+        local = frame->local;

+        loc = &local->loc;

+

+        inode_unref (loc->inode);

+        loc->inode = inode_new (loc->parent->table);

+        if (!loc->inode) {

+                gf_log (this->name, GF_LOG_ERROR, "failed to "

+                        "allocate new inode");

+                goto out;

+        }

+

+        gf_uuid_copy (local->loc.gfid, loc->inode->gfid);

+        ret = inode_path (loc->parent, private->path, &path);

+        if (ret < 0)

+                goto out;

+

+        if (loc->path)

+                GF_FREE ((char *)loc->path);

+

+        loc->path = gf_strdup (path);

+        if (loc->path) {

+                if (!loc->name ||

+                    (loc->name && !strcmp (loc->name, ""))) {

+                        loc->name = strrchr (loc->path, '/');

+                        if (loc->name)

+                                loc->name++;

+                }

+        } else

+                loc->path = NULL;

+

+        tmp_xdata = dict_new ();

+        if (!tmp_xdata) {

+                ret = -1;

+                goto out;

+        }

+

+        ret = dict_set_str (tmp_xdata, "entry-point", "true");

+        if (ret) {

+                gf_log (this->name, GF_LOG_ERROR, "failed to set dict");

+                goto out;

+        }

+

+        STACK_WIND (frame, gf_svc_readdirp_lookup_cbk,

+                    SECOND_CHILD (this),

+                    SECOND_CHILD (this)->fops->lookup, loc,

+                    tmp_xdata);

+out:

+        if (tmp_xdata)

+                dict_unref (tmp_xdata);

+

+        GF_FREE (path);

+        return ret;

+}

+

 static gf_boolean_t

 gf_svc_readdir_on_special_dir (call_frame_t *frame, void *cookie,

                                xlator_t *this, int32_t op_ret,

diff --git a/xlators/features/snapview-client/src/snapview-client.h b/xlators/features/snapview-client/src/snapview-client.h

index 5b7a862..e1fcb37 100644

--- a/xlators/features/snapview-client/src/snapview-client.h

+++ b/xlators/features/snapview-client/src/snapview-client.h

@@ -23,6 +23,7 @@ struct __svc_local {

         fd_t     *fd;

         void *cookie;

         dict_t *xdata;

+        uint16_t revalidate;

 };

 typedef struct __svc_local svc_local_t;

@@ -94,4 +95,7 @@ typedef enum {

         VIRTUAL_INODE

 } inode_type_t;

+int

+gf_svc_special_dir_revalidate_lookup (call_frame_t *frame, xlator_t *this);

+

 #endif /* __SNAP_VIEW_CLIENT_H__ */

-- 

1.8.3.1