From 203bc643db59e2538e9a3f19be1636cdfd2bb2db Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 11 May 2015 08:29:30 -0400 Subject: update Documentation/filesystems/ regarding the follow_link/put_link changes Signed-off-by: Al Viro --- Documentation/filesystems/vfs.txt | 18 ++++++++++-------- 1 file changed, 10 insertions(+), 8 deletions(-) (limited to 'Documentation/filesystems/vfs.txt') diff --git a/Documentation/filesystems/vfs.txt b/Documentation/filesystems/vfs.txt index 542d9352d0f2..b403b29ef710 100644 --- a/Documentation/filesystems/vfs.txt +++ b/Documentation/filesystems/vfs.txt @@ -436,16 +436,18 @@ otherwise noted. follow_link: called by the VFS to follow a symbolic link to the inode it points to. Only required if you want to support - symbolic links. This method returns a void pointer cookie - that is passed to put_link(). + symbolic links. This method returns the symlink body + to traverse (and possibly resets the current position with + nd_jump_link()). If the body won't go away until the inode + is gone, nothing else is needed; if it needs to be otherwise + pinned, the data needed to release whatever we'd grabbed + is to be stored in void * variable passed by address to + follow_link() instance. put_link: called by the VFS to release resources allocated by - follow_link(). The cookie returned by follow_link() is passed - to this method as the last parameter. It is used by - filesystems such as NFS where page cache is not stable - (i.e. page that was installed when the symbolic link walk - started might not be in the page cache at the end of the - walk). + follow_link(). The cookie stored by follow_link() is passed + to this method as the last parameter; only called when + cookie isn't NULL. permission: called by the VFS to check for access rights on a POSIX-like filesystem. -- cgit