fs: provide rcu-walk aware permission i_ops

Signed-off-by: Nick Piggin <npiggin@kernel.dk>

1 files changed, 5 insertions, 2 deletions

diff --git a/fs/hostfs/hostfs_kern.c b/fs/hostfs/hostfs_kern.c
index 0bc81cf256b8..d3244d949a4e 100644
--- a/fs/hostfs/hostfs_kern.c
+++ b/fs/hostfs/hostfs_kern.c
@@ -749,11 +749,14 @@ int hostfs_rename(struct inode *from_ino, struct dentry *from,
         return err;
 }
 
-int hostfs_permission(struct inode *ino, int desired)
+int hostfs_permission(struct inode *ino, int desired, unsigned int flags)
 {
         char *name;
         int r = 0, w = 0, x = 0, err;
 
+        if (flags & IPERM_FLAG_RCU)
+                return -ECHILD;
+
         if (desired & MAY_READ) r = 1;
         if (desired & MAY_WRITE) w = 1;
         if (desired & MAY_EXEC) x = 1;
@@ -768,7 +771,7 @@ int hostfs_permission(struct inode *ino, int desired)
                 err = access_file(name, r, w, x);
         __putname(name);
         if (!err)
-                err = generic_permission(ino, desired, NULL);
+                err = generic_permission(ino, desired, flags, NULL);
         return err;
 }