fs: provide rcu-walk aware permission i_ops

[pandora-kernel.git] / Documentation / filesystems / vfs.txt

diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt
index c936b49..fbb324e 100644 (file)
--- a/Documentation/filesystems/vfs.txt
+++ b/Documentation/filesystems/vfs.txt
@@ -325,7 +325,8 @@ struct inode_operations {
         void * (*follow_link) (struct dentry *, struct nameidata *);
         void (*put_link) (struct dentry *, struct nameidata *, void *);
        void (*truncate) (struct inode *);
-       int (*permission) (struct inode *, int, struct nameidata *);
+       int (*permission) (struct inode *, int, unsigned int);
+       int (*check_acl)(struct inode *, int, unsigned int);
        int (*setattr) (struct dentry *, struct iattr *);
        int (*getattr) (struct vfsmount *mnt, struct dentry *, struct kstat *);
        int (*setxattr) (struct dentry *, const char *,const void *,size_t,int);
@@ -414,6 +415,13 @@ otherwise noted.
   permission: called by the VFS to check for access rights on a POSIX-like
        filesystem.
 
+       May be called in rcu-walk mode (flags & IPERM_RCU). If in rcu-walk
+       mode, the filesystem must check the permission without blocking or
+       storing to the inode.
+
+       If a situation is encountered that rcu-walk cannot handle, return
+       -ECHILD and it will be called again in ref-walk mode.
+
   setattr: called by the VFS to set attributes for a file. This method
        is called by chmod(2) and related system calls.