fs: provide rcu-walk aware permission i_ops

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

2 files changed, 7 insertions, 3 deletions

diff --git a/fs/ext4/acl.c b/fs/ext4/acl.c
index 5e2ed4504ead..373dcaeedba9 100644
--- a/fs/ext4/acl.c
+++ b/fs/ext4/acl.c
@@ -238,10 +238,14 @@ ext4_set_acl(handle_t *handle, struct inode *inode, int type,
 }
 
 int
-ext4_check_acl(struct inode *inode, int mask)
+ext4_check_acl(struct inode *inode, int mask, unsigned int flags)
 {
-        struct posix_acl *acl = ext4_get_acl(inode, ACL_TYPE_ACCESS);
+        struct posix_acl *acl;
+
+        if (flags & IPERM_FLAG_RCU)
+                return -ECHILD;
 
+        acl = ext4_get_acl(inode, ACL_TYPE_ACCESS);
         if (IS_ERR(acl))
                 return PTR_ERR(acl);
         if (acl) {
diff --git a/fs/ext4/acl.h b/fs/ext4/acl.h
index 9d843d5deac4..dec821168fd4 100644
--- a/fs/ext4/acl.h
+++ b/fs/ext4/acl.h
@@ -54,7 +54,7 @@ static inline int ext4_acl_count(size_t size)
 #ifdef CONFIG_EXT4_FS_POSIX_ACL
 
 /* acl.c */
-extern int ext4_check_acl(struct inode *, int);
+extern int ext4_check_acl(struct inode *, int, unsigned int);
 extern int ext4_acl_chmod(struct inode *);
 extern int ext4_init_acl(handle_t *, struct inode *, struct inode *);