From 8f811b1ef400035eaf1adf38db24cc33a8726aab Mon Sep 17 00:00:00 2001

From: Raghavendra G <rgowdapp@redhat.com>

Date: Fri, 26 Jun 2015 11:53:11 +0530

Subject: [PATCH 197/200] cluster/dht: use refcount to manage memory used to store migration

 information.

Without refcounting, we might free up memory while other fops are

still accessing it.

BUG: 1238167

Change-Id: Ia4fa4a651cd6fe2394a0c20cef83c8d2cbc8750f

Signed-off-by: Raghavendra G <rgowdapp@redhat.com>

Reviewed-on: http://review.gluster.org/11418

Reviewed-by: Shyamsundar Ranganathan <srangana@redhat.com>

Tested-by: Gluster Build System <jenkins@build.gluster.com>

Reviewed-by: N Balachandran <nbalacha@redhat.com>

Tested-by: NetBSD Build System <jenkins@build.gluster.org>

Reviewed-on: https://code.engineering.redhat.com/gerrit/52107

Reviewed-by: Nithya Balachandran <nbalacha@redhat.com>

---

 xlators/cluster/dht/src/dht-common.h |    2 +

 xlators/cluster/dht/src/dht-helper.c |   65 +++++++++++++++++++++++-----------

 2 files changed, 46 insertions(+), 21 deletions(-)

diff --git a/xlators/cluster/dht/src/dht-common.h b/xlators/cluster/dht/src/dht-common.h

index c04e85d..5e86b32 100644

--- a/xlators/cluster/dht/src/dht-common.h

+++ b/xlators/cluster/dht/src/dht-common.h

@@ -20,6 +20,7 @@

 #include "dht-messages.h"

 #include "libxlator.h"

 #include "syncop.h"

+#include "refcount.h"

 #ifndef _DHT_H

 #define _DHT_H

@@ -506,6 +507,7 @@ struct dir_dfmeta {

 typedef struct dht_migrate_info {

         xlator_t *src_subvol;

         xlator_t *dst_subvol;

+        GF_REF_DECL;

 } dht_migrate_info_t;

 #define ENTRY_MISSING(op_ret, op_errno) (op_ret == -1 && op_errno == ENOENT)

diff --git a/xlators/cluster/dht/src/dht-helper.c b/xlators/cluster/dht/src/dht-helper.c

index 6742f29..d8cc61d 100644

--- a/xlators/cluster/dht/src/dht-helper.c

+++ b/xlators/cluster/dht/src/dht-helper.c

@@ -19,6 +19,17 @@

 #include "dht-common.h"

 #include "dht-helper.h"

+void

+dht_free_mig_info (void *data)

+{

+        dht_migrate_info_t *miginfo = NULL;

+

+        miginfo = data;

+        GF_FREE (miginfo);

+

+        return;

+}

+

 static inline int

 dht_inode_ctx_set_mig_info (xlator_t *this, inode_t *inode,

                             xlator_t *src_subvol, xlator_t *dst_subvol)

@@ -33,12 +44,13 @@ dht_inode_ctx_set_mig_info (xlator_t *this, inode_t *inode,

         miginfo->src_subvol = src_subvol;

         miginfo->dst_subvol = dst_subvol;

+        GF_REF_INIT (miginfo, dht_free_mig_info);

         value = (uint64_t) miginfo;

         ret = inode_ctx_set1 (inode, this, &value);

         if (ret < 0) {

-                GF_FREE (miginfo);

+                GF_REF_PUT (miginfo);

         }

 out:

@@ -54,11 +66,18 @@ dht_inode_ctx_get_mig_info (xlator_t *this, inode_t *inode,

         uint64_t            tmp_miginfo = 0;

         dht_migrate_info_t *miginfo     = NULL;

-        ret =  inode_ctx_get1 (inode, this, &tmp_miginfo);

-        if ((ret < 0) || (tmp_miginfo == 0))

-                goto out;

+        LOCK (&inode->lock);

+        {

+                ret =  __inode_ctx_get1 (inode, this, &tmp_miginfo);

+                if ((ret < 0) || (tmp_miginfo == 0)) {

+                        UNLOCK (&inode->lock);

+                        goto out;

+                }

-        miginfo = (dht_migrate_info_t *)tmp_miginfo;

+                miginfo = (dht_migrate_info_t *)tmp_miginfo;

+                GF_REF_GET (miginfo);

+        }

+        UNLOCK (&inode->lock);

         if (src_subvol)

                 *src_subvol = miginfo->src_subvol;

@@ -66,6 +85,8 @@ dht_inode_ctx_get_mig_info (xlator_t *this, inode_t *inode,

         if (dst_subvol)

                 *dst_subvol = miginfo->dst_subvol;

+        GF_REF_PUT (miginfo);

+

 out:

         return ret;

 }

@@ -900,21 +921,22 @@ out:

 int

 dht_migration_complete_check_task (void *data)

 {

-        int           ret         = -1;

-        xlator_t     *src_node    = NULL;

-        xlator_t     *dst_node    = NULL, *linkto_target = NULL;

-        dht_local_t  *local       = NULL;

-        dict_t       *dict        = NULL;

-        struct iatt   stbuf       = {0,};

-        xlator_t     *this        = NULL;

-        call_frame_t *frame       = NULL;

-        loc_t         tmp_loc     = {0,};

-        char         *path        = NULL;

-        dht_conf_t   *conf        = NULL;

-        inode_t      *inode       = NULL;

-        fd_t         *iter_fd     = NULL;

-        uint64_t      tmp_miginfo = 0;

-        int           open_failed = 0;

+        int                 ret         = -1;

+        xlator_t           *src_node    = NULL;

+        xlator_t           *dst_node    = NULL, *linkto_target = NULL;

+        dht_local_t        *local       = NULL;

+        dict_t             *dict        = NULL;

+        struct iatt         stbuf       = {0,};

+        xlator_t           *this        = NULL;

+        call_frame_t       *frame       = NULL;

+        loc_t               tmp_loc     = {0,};

+        char               *path        = NULL;

+        dht_conf_t         *conf        = NULL;

+        inode_t            *inode       = NULL;

+        fd_t               *iter_fd     = NULL;

+        uint64_t            tmp_miginfo = 0;

+        dht_migrate_info_t *miginfo     = NULL;

+        int                 open_failed = 0;

         this  = THIS;

         frame = data;

@@ -1018,7 +1040,8 @@ dht_migration_complete_check_task (void *data)

            done on all the fd of inode */

         ret = inode_ctx_reset1 (inode, this, &tmp_miginfo);

         if (tmp_miginfo) {

-                GF_FREE ((void *)tmp_miginfo);

+                miginfo = (void *)tmp_miginfo;

+                GF_REF_PUT (miginfo);

                 goto out;

         }

-- 

1.7.1