ocfs2: implement i_op->permission

Implement .permission() in ocfs2_file_iops, ocfs2_special_file_iops and
ocfs2_dir_iops.

This helps us avoid some multi-node races with mode change and vfs
operations.

Signed-off-by: Tiger Yang <tiger.yang@oracle.com>
Signed-off-by: Mark Fasheh <mark.fasheh@oracle.com>

3 files changed, 27 insertions, 0 deletions

diff --git a/fs/ocfs2/file.c b/fs/ocfs2/file.c
index b64ef7c6e2d2..8786b3c490aa 100644
--- a/fs/ocfs2/file.c
+++ b/fs/ocfs2/file.c
@@ -945,6 +945,28 @@ bail:
         return err;
 }
 
+int ocfs2_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+        int ret;
+
+        mlog_entry_void();
+
+        ret = ocfs2_meta_lock(inode, NULL, 0);
+        if (ret) {
+                mlog_errno(ret);
+                goto out;
+        }
+
+        ret = generic_permission(inode, mask, NULL);
+        if (ret)
+                mlog_errno(ret);
+
+        ocfs2_meta_unlock(inode, 0);
+out:
+        mlog_exit(ret);
+        return ret;
+}
+
 static int ocfs2_write_remove_suid(struct inode *inode)
 {
         int ret;
@@ -1329,11 +1351,13 @@ bail:
 struct inode_operations ocfs2_file_iops = {
         .setattr        = ocfs2_setattr,
         .getattr        = ocfs2_getattr,
+        .permission     = ocfs2_permission,
 };
 
 struct inode_operations ocfs2_special_file_iops = {
         .setattr        = ocfs2_setattr,
         .getattr        = ocfs2_getattr,
+        .permission     = ocfs2_permission,
 };
 
 const struct file_operations ocfs2_fops = {
diff --git a/fs/ocfs2/file.h b/fs/ocfs2/file.h
index 475ed8aee8b5..601a453f18a8 100644
--- a/fs/ocfs2/file.h
+++ b/fs/ocfs2/file.h
@@ -48,6 +48,8 @@ int ocfs2_do_extend_allocation(struct ocfs2_super *osb,
 int ocfs2_setattr(struct dentry *dentry, struct iattr *attr);
 int ocfs2_getattr(struct vfsmount *mnt, struct dentry *dentry,
                   struct kstat *stat);
+int ocfs2_permission(struct inode *inode, int mask,
+                     struct nameidata *nd);
 
 int ocfs2_set_inode_size(handle_t *handle,
                          struct inode *inode,
diff --git a/fs/ocfs2/namei.c b/fs/ocfs2/namei.c
index 583bffe98091..21db45ddf144 100644
--- a/fs/ocfs2/namei.c
+++ b/fs/ocfs2/namei.c
@@ -2311,4 +2311,5 @@ struct inode_operations ocfs2_dir_iops = {
         .rename         = ocfs2_rename,
         .setattr        = ocfs2_setattr,
         .getattr        = ocfs2_getattr,
+        .permission     = ocfs2_permission,
 };