4 files changed, 31 insertions, 12 deletions

diff --git a/fs/9p/acl.c b/fs/9p/acl.c
index 0a2e480477a5..1ee3434239c8 100644
--- a/fs/9p/acl.c
+++ b/fs/9p/acl.c
@@ -59,7 +59,8 @@ int v9fs_get_acl(struct inode *inode, struct p9_fid *fid)
         struct v9fs_session_info *v9ses;
 
         v9ses = v9fs_inode2v9ses(inode);
-        if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) {
+        if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
+                        ((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
                 set_cached_acl(inode, ACL_TYPE_DEFAULT, NULL);
                 set_cached_acl(inode, ACL_TYPE_ACCESS, NULL);
                 return 0;
@@ -104,9 +105,10 @@ int v9fs_check_acl(struct inode *inode, int mask, unsigned int flags)
                 return -ECHILD;
 
         v9ses = v9fs_inode2v9ses(inode);
-        if ((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) {
+        if (((v9ses->flags & V9FS_ACCESS_MASK) != V9FS_ACCESS_CLIENT) ||
+                        ((v9ses->flags & V9FS_ACL_MASK) != V9FS_POSIX_ACL)) {
                 /*
-                 * On access = client mode get the acl
+                 * On access = client  and acl = on mode get the acl
                  * values from the server
                  */
                 return 0;
diff --git a/fs/9p/v9fs.c b/fs/9p/v9fs.c
index d34f2937df66..f5a3200877d6 100644
--- a/fs/9p/v9fs.c
+++ b/fs/9p/v9fs.c
@@ -55,7 +55,7 @@ enum {
         /* Cache options */
         Opt_cache_loose, Opt_fscache,
         /* Access options */
-        Opt_access,
+        Opt_access, Opt_posixacl,
         /* Error token */
         Opt_err
 };
@@ -73,6 +73,7 @@ static const match_table_t tokens = {
         {Opt_fscache, "fscache"},
         {Opt_cachetag, "cachetag=%s"},
         {Opt_access, "access=%s"},
+        {Opt_posixacl, "posixacl"},
         {Opt_err, NULL}
 };
 
@@ -194,13 +195,7 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
                         else if (strcmp(s, "any") == 0)
                                 v9ses->flags |= V9FS_ACCESS_ANY;
                         else if (strcmp(s, "client") == 0) {
-#ifdef CONFIG_9P_FS_POSIX_ACL
                                 v9ses->flags |= V9FS_ACCESS_CLIENT;
-#else
-                                P9_DPRINTK(P9_DEBUG_ERROR,
-                                        "Not defined CONFIG_9P_FS_POSIX_ACL. "
-                                        "Ignoring access=client option\n");
-#endif
                         } else {
                                 v9ses->flags |= V9FS_ACCESS_SINGLE;
                                 v9ses->uid = simple_strtoul(s, &e, 10);
@@ -210,6 +205,16 @@ static int v9fs_parse_options(struct v9fs_session_info *v9ses, char *opts)
                         kfree(s);
                         break;
 
+                case Opt_posixacl:
+#ifdef CONFIG_9P_FS_POSIX_ACL
+                        v9ses->flags |= V9FS_POSIX_ACL;
+#else
+                        P9_DPRINTK(P9_DEBUG_ERROR,
+                                        "Not defined CONFIG_9P_FS_POSIX_ACL. "
+                                        "Ignoring posixacl option\n");
+#endif
+                        break;
+
                 default:
                         continue;
                 }
@@ -304,6 +309,14 @@ struct p9_fid *v9fs_session_init(struct v9fs_session_info *v9ses,
                 v9ses->flags |= V9FS_ACCESS_ANY;
                 v9ses->uid = ~0;
         }
+        if (!v9fs_proto_dotl(v9ses) ||
+                !((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)) {
+                /*
+                 * We support ACL checks on clinet only if the protocol is
+                 * 9P2000.L and access is V9FS_ACCESS_CLIENT.
+                 */
+                v9ses->flags &= ~V9FS_ACL_MASK;
+        }
 
         fid = p9_client_attach(v9ses->clnt, NULL, v9ses->uname, ~0,
                                                         v9ses->aname);
diff --git a/fs/9p/v9fs.h b/fs/9p/v9fs.h
index c4b5d8864f0d..6fa3cf5547d5 100644
--- a/fs/9p/v9fs.h
+++ b/fs/9p/v9fs.h
@@ -28,8 +28,10 @@
  * @V9FS_PROTO_2000L: whether or not to use 9P2000.l extensions
  * @V9FS_ACCESS_SINGLE: only the mounting user can access the hierarchy
  * @V9FS_ACCESS_USER: a new attach will be issued for every user (default)
+ * @V9FS_ACCESS_CLIENT: Just like user, but access check is performed on client.
  * @V9FS_ACCESS_ANY: use a single attach for all users
  * @V9FS_ACCESS_MASK: bit mask of different ACCESS options
+ * @V9FS_POSIX_ACL: POSIX ACLs are enforced
  *
  * Session flags reflect options selected by users at mount time
  */
@@ -37,13 +39,15 @@
                          V9FS_ACCESS_USER |   \
                          V9FS_ACCESS_CLIENT)
 #define V9FS_ACCESS_MASK V9FS_ACCESS_ANY
+#define V9FS_ACL_MASK V9FS_POSIX_ACL
 
 enum p9_session_flags {
         V9FS_PROTO_2000U        = 0x01,
         V9FS_PROTO_2000L        = 0x02,
         V9FS_ACCESS_SINGLE      = 0x04,
         V9FS_ACCESS_USER        = 0x08,
-        V9FS_ACCESS_CLIENT      = 0x10
+        V9FS_ACCESS_CLIENT      = 0x10,
+        V9FS_POSIX_ACL          = 0x20
 };
 
 /* possible values of ->cache */
diff --git a/fs/9p/vfs_super.c b/fs/9p/vfs_super.c
index dbaabe3b8131..4f14be585d6c 100644
--- a/fs/9p/vfs_super.c
+++ b/fs/9p/vfs_super.c
@@ -91,7 +91,7 @@ v9fs_fill_super(struct super_block *sb, struct v9fs_session_info *v9ses,
             MS_NOATIME;
 
 #ifdef CONFIG_9P_FS_POSIX_ACL
-        if ((v9ses->flags & V9FS_ACCESS_MASK) == V9FS_ACCESS_CLIENT)
+        if ((v9ses->flags & V9FS_ACL_MASK) == V9FS_POSIX_ACL)
                 sb->s_flags |= MS_POSIXACL;
 #endif