/*
* JFFS2 -- Journalling Flash File System, Version 2.
*
* Copyright © 2001-2007 Red Hat, Inc.
*
* Created by David Woodhouse <dwmw2@infradead.org>
*
* For licensing information, see the file 'LICENCE' in this directory.
*
*/
#include <linux/kernel.h>
#include <linux/sched.h>
#include <linux/slab.h>
#include <linux/fs.h>
#include <linux/crc32.h>
#include <linux/pagemap.h>
#include <linux/mtd/mtd.h>
#include <linux/compiler.h>
#include "nodelist.h"
/*
* Check the data CRC of the node.
*
* Returns: 0 if the data CRC is correct;
* 1 - if incorrect;
* error code if an error occured.
*/
static int check_node_data(struct jffs2_sb_info *c, struct jffs2_tmp_dnode_info *tn)
{
struct jffs2_raw_node_ref *ref = tn->fn->raw;
int err = 0, pointed = 0;
struct jffs2_eraseblock *jeb;
unsigned char *buffer;
uint32_t crc, ofs, len;
size_t retlen;
BUG_ON(tn->csize == 0);
/* Calculate how many bytes were already checked */
ofs = ref_offset(ref) + sizeof(struct jffs2_raw_inode);
len = tn->csize;
if (jffs2_is_writebuffered(c)) {
int adj = ofs % c->wbuf_pagesize;
if (likely(adj))
adj = c->wbuf_pagesize - adj;
if (adj >= tn->csize) {
dbg_readinode("no need to check node at %#08x, data length %u, data starts at %#08x - it has already been checked.\n",
ref_offset(ref), tn->csize, ofs);
goto adj_acc;
}
ofs += adj;
len -= adj;
}
dbg_readinode("check node at %#08x, data length %u, partial CRC %#08x, correct CRC %#08x, data starts at %#08x, start checking from %#08x - %u bytes.\n",
ref_offset(ref), tn->csize, tn->partial_crc, tn->data_crc, ofs - len, ofs, len);
#ifndef __ECOS
/* TODO: instead, incapsulate point() stuff to jffs2_flash_read(),
* adding and jffs2_flash_read_end() interface. */
if (c->mtd->point) {
err = c->mtd->point(c->mtd, ofs, len, &retlen,
(void **)&buffer, NULL);
if (!err && retlen < len) {
JFFS2_WARNING("MTD point returned len too short: %zu instead of %u.\n", retlen, tn->csize);
c->mtd->unpoint(c->mtd, ofs, retlen);
} else if (err)
JFFS2_WARNING("MTD point failed: error code %d.\n", err);
else
pointed = 1; /* succefully pointed to device */
}
#endif
if (!pointed) {
buffer = kmalloc(len, GFP_KERNEL);
if (unlikely(!buffer))
return -ENOMEM;
/* TODO: this is very frequent pattern, make it a separate
* routine */
err = jffs2_flash_read(c, ofs, len, &retlen, buffer);
if (err) {
JFFS2_ERROR("can not read %d bytes from 0x%08x, error code: %d.\n", len, ofs, err);
goto free_out;
}
if (retlen != len) {
JF
| 