• Linus Torvalds's avatar
    devpts: more pty driver interface cleanups · 8ead9dd5
    Linus Torvalds authored
    This is more prep-work for the upcoming pty changes.  Still just code
    cleanup with no actual semantic changes.
    This removes a bunch pointless complexity by just having the slave pty
    side remember the dentry associated with the devpts slave rather than
    the inode.  That allows us to remove all the "look up the dentry" code
    for when we want to remove it again.
    Together with moving the tty pointer from "inode->i_private" to
    "dentry->d_fsdata" and getting rid of pointless inode locking, this
    removes about 30 lines of code.  Not only is the end result smaller,
    it's simpler and easier to understand.
    The old code, for example, depended on the d_find_alias() to not just
    find the dentry, but also to check that it is still hashed, which in
    turn validated the tty pointer in the inode.
    That is a _very_ roundabout way to say "invalidate the cached tty
    pointer when the dentry is removed".
    The new code just does
    	dentry->d_fsdata = NULL;
    in devpts_pty_kill() instead, invalidating the tty pointer rather more
    directly and obviously.  Don't do something complex and subtle when the
    obvious straightforward approach will do.
    The rest of the patch (ie apart from code deletion and the above tty
    pointer clearing) is just switching the calling convention to pass the
    dentry or file pointer around instead of the inode.
    Cc: Eric Biederman <ebiederm@xmission.com>
    Cc: Peter Anvin <hpa@zytor.com>
    Cc: Andy Lutomirski <luto@amacapital.net>
    Cc: Al Viro <viro@zeniv.linux.org.uk>
    Cc: Peter Hurley <peter@hurleysoftware.com>
    Cc: Serge Hallyn <serge.hallyn@ubuntu.com>
    Cc: Willy Tarreau <w@1wt.eu>
    Cc: Aurelien Jarno <aurelien@aurel32.net>
    Cc: Alan Cox <gnomes@lxorguk.ukuu.org.uk>
    Cc: Jann Horn <jann@thejh.net>
    Cc: Greg KH <greg@kroah.com>
    Cc: Jiri Slaby <jslaby@suse.com>
    Cc: Florian Weimer <fw@deneb.enyo.de>
    Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
Last commit
Last update
Makefile Loading commit data...
inode.c Loading commit data...