android_kernel_google_msm/fs/jffs2/symlink.c
Artem B. Bityutskiy 2b79adcca1 [JFFS2] Use f->target instead of f->dents for symlink target
JFFS2 uses f->dents to store the pointer to the symlink target string (in case
the inode is symlink). This is somewhat ugly to use the same field for
different reasons. Introduce distinct field f->target for this purpose.
Note, f->fragtree, f->dents, f->target may probably be put in a union.

Signed-off-by: Artem B. Bityutskiy <dedekind@infradead.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
2005-11-06 16:25:55 +01:00

63 lines
1.8 KiB
C

/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright (C) 2001, 2002 Red Hat, Inc.
*
* Created by David Woodhouse <dwmw2@infradead.org>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
* $Id: symlink.c,v 1.18 2005/11/06 11:03:27 gleixner Exp $
*
*/
#include <linux/kernel.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/namei.h>
#include "nodelist.h"
static void *jffs2_follow_link(struct dentry *dentry, struct nameidata *nd);
struct inode_operations jffs2_symlink_inode_operations =
{
.readlink = generic_readlink,
.follow_link = jffs2_follow_link,
.setattr = jffs2_setattr
};
static void *jffs2_follow_link(struct dentry *dentry, struct nameidata *nd)
{
struct jffs2_inode_info *f = JFFS2_INODE_INFO(dentry->d_inode);
char *p = (char *)f->target;
/*
* We don't acquire the f->sem mutex here since the only data we
* use is f->target.
*
* 1. If we are here the inode has already built and f->target has
* to point to the target path.
* 2. Nobody uses f->target (if the inode is symlink's inode). The
* exception is inode freeing function which frees f->target. But
* it can't be called while we are here and before VFS has
* stopped using our f->target string which we provide by means of
* nd_set_link() call.
*/
if (!p) {
printk(KERN_ERR "jffs2_follow_link(): can't find symlink taerget\n");
p = ERR_PTR(-EIO);
}
D1(printk(KERN_DEBUG "jffs2_follow_link(): target path is '%s'\n", (char *) f->target));
nd_set_link(nd, p);
/*
* We will unlock the f->sem mutex but VFS will use the f->target string. This is safe
* since the only way that may cause f->target to be changed is iput() operation.
* But VFS will not use f->target after iput() has been called.
*/
return NULL;
}