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1275 |
phoenix |
/*
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* JFFS2 -- Journalling Flash File System, Version 2.
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*
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* Copyright (C) 2001 Red Hat, Inc.
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*
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* Created by David Woodhouse <dwmw2@cambridge.redhat.com>
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*
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* The original JFFS, from which the design for JFFS2 was derived,
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* was designed and implemented by Axis Communications AB.
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*
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* The contents of this file are subject to the Red Hat eCos Public
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* License Version 1.1 (the "Licence"); you may not use this file
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* except in compliance with the Licence. You may obtain a copy of
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* the Licence at http://www.redhat.com/
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*
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* Software distributed under the Licence is distributed on an "AS IS"
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* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied.
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* See the Licence for the specific language governing rights and
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* limitations under the Licence.
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*
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* The Original Code is JFFS2 - Journalling Flash File System, version 2
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*
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* Alternatively, the contents of this file may be used under the
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* terms of the GNU General Public License version 2 (the "GPL"), in
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* which case the provisions of the GPL are applicable instead of the
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* above. If you wish to allow the use of your version of this file
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* only under the terms of the GPL and not to allow others to use your
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* version of this file under the RHEPL, indicate your decision by
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* deleting the provisions above and replace them with the notice and
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* other provisions required by the GPL. If you do not delete the
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* provisions above, a recipient may use your version of this file
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* under either the RHEPL or the GPL.
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*
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* $Id: scan.c,v 1.1.1.1 2004-04-15 01:11:08 phoenix Exp $
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*
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*/
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#include <linux/kernel.h>
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#include <linux/slab.h>
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#include <linux/jffs2.h>
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#include <linux/mtd/mtd.h>
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#include <linux/pagemap.h>
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#include "nodelist.h"
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#include <linux/crc32.h>
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#define DIRTY_SPACE(x) do { typeof(x) _x = (x); \
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c->free_size -= _x; c->dirty_size += _x; \
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jeb->free_size -= _x ; jeb->dirty_size += _x; \
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}while(0)
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#define USED_SPACE(x) do { typeof(x) _x = (x); \
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c->free_size -= _x; c->used_size += _x; \
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jeb->free_size -= _x ; jeb->used_size += _x; \
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}while(0)
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#define noisy_printk(noise, args...) do { \
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if (*(noise)) { \
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printk(KERN_NOTICE args); \
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(*(noise))--; \
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if (!(*(noise))) { \
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printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \
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} \
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} \
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} while(0)
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| 65 |
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static uint32_t pseudo_random;
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| 66 |
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static void jffs2_rotate_lists(struct jffs2_sb_info *c);
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| 68 |
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static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
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/* These helper functions _must_ increase ofs and also do the dirty/used space accounting.
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* Returning an error will abort the mount - bad checksums etc. should just mark the space
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* as dirty.
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*/
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static int jffs2_scan_empty(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, __u32 *ofs, int *noise);
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static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, __u32 *ofs);
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static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, __u32 *ofs);
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int jffs2_scan_medium(struct jffs2_sb_info *c)
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{
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int i, ret;
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| 82 |
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__u32 empty_blocks = 0;
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| 83 |
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| 84 |
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if (!c->blocks) {
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printk(KERN_WARNING "EEEK! c->blocks is NULL!\n");
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return -EINVAL;
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}
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| 88 |
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for (i=0; i<c->nr_blocks; i++) {
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struct jffs2_eraseblock *jeb = &c->blocks[i];
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| 90 |
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| 91 |
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ret = jffs2_scan_eraseblock(c, jeb);
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| 92 |
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if (ret < 0)
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return ret;
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| 95 |
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ACCT_PARANOIA_CHECK(jeb);
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/* Now decide which list to put it on */
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if (ret == 1) {
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/*
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* Empty block. Since we can't be sure it
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* was entirely erased, we just queue it for erase
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| 102 |
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* again. It will be marked as such when the erase
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* is complete. Meanwhile we still count it as empty
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| 104 |
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* for later checks.
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*/
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| 106 |
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list_add(&jeb->list, &c->erase_pending_list);
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empty_blocks++;
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| 108 |
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c->nr_erasing_blocks++;
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| 109 |
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} else if (jeb->used_size == PAD(sizeof(struct jffs2_unknown_node)) && !jeb->first_node->next_in_ino) {
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| 110 |
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/* Only a CLEANMARKER node is valid */
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if (!jeb->dirty_size) {
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/* It's actually free */
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list_add(&jeb->list, &c->free_list);
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c->nr_free_blocks++;
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| 115 |
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} else {
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/* Dirt */
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| 117 |
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D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset));
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list_add(&jeb->list, &c->erase_pending_list);
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| 119 |
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c->nr_erasing_blocks++;
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| 120 |
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}
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| 121 |
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} else if (jeb->used_size > c->sector_size - (2*sizeof(struct jffs2_raw_inode))) {
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| 122 |
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/* Full (or almost full) of clean data. Clean list */
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list_add(&jeb->list, &c->clean_list);
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| 124 |
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} else if (jeb->used_size) {
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| 125 |
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/* Some data, but not full. Dirty list. */
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| 126 |
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/* Except that we want to remember the block with most free space,
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| 127 |
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and stick it in the 'nextblock' position to start writing to it.
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| 128 |
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Later when we do snapshots, this must be the most recent block,
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| 129 |
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not the one with most free space.
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| 130 |
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*/
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| 131 |
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if (jeb->free_size > 2*sizeof(struct jffs2_raw_inode) &&
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| 132 |
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(!c->nextblock || c->nextblock->free_size < jeb->free_size)) {
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| 133 |
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/* Better candidate for the next writes to go to */
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if (c->nextblock)
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| 135 |
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list_add(&c->nextblock->list, &c->dirty_list);
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c->nextblock = jeb;
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} else {
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list_add(&jeb->list, &c->dirty_list);
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| 139 |
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}
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| 140 |
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} else {
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| 141 |
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/* Nothing valid - not even a clean marker. Needs erasing. */
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| 142 |
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/* For now we just put it on the erasing list. We'll start the erases later */
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| 143 |
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printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset);
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list_add(&jeb->list, &c->erase_pending_list);
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| 145 |
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c->nr_erasing_blocks++;
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}
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| 147 |
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}
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| 148 |
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/* Rotate the lists by some number to ensure wear levelling */
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jffs2_rotate_lists(c);
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| 151 |
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if (c->nr_erasing_blocks) {
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| 152 |
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if (!c->used_size && empty_blocks != c->nr_blocks) {
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| 153 |
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printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n");
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| 154 |
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return -EIO;
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| 155 |
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}
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| 156 |
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jffs2_erase_pending_trigger(c);
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| 157 |
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}
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| 158 |
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return 0;
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| 159 |
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}
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| 160 |
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| 161 |
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static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb) {
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struct jffs2_unknown_node node;
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| 163 |
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__u32 ofs, prevofs;
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| 164 |
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__u32 hdr_crc, nodetype;
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| 165 |
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int err;
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| 166 |
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int noise = 0;
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| 167 |
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| 168 |
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ofs = jeb->offset;
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| 169 |
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prevofs = jeb->offset - 1;
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| 170 |
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| 171 |
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D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));
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| 172 |
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| 173 |
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err = jffs2_scan_empty(c, jeb, &ofs, &noise);
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| 174 |
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if (err) return err;
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| 175 |
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if (ofs == jeb->offset + c->sector_size) {
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| 176 |
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D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
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| 177 |
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return 1; /* special return code */
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| 178 |
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}
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| 179 |
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| 180 |
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noise = 10;
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| 181 |
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| 182 |
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while(ofs < jeb->offset + c->sector_size) {
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| 183 |
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ssize_t retlen;
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| 184 |
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ACCT_PARANOIA_CHECK(jeb);
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| 185 |
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| 186 |
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if (ofs & 3) {
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| 187 |
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printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
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| 188 |
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ofs = (ofs+3)&~3;
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| 189 |
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continue;
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| 190 |
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}
|
| 191 |
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if (ofs == prevofs) {
|
| 192 |
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printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
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| 193 |
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DIRTY_SPACE(4);
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| 194 |
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ofs += 4;
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| 195 |
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continue;
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| 196 |
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}
|
| 197 |
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prevofs = ofs;
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| 198 |
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|
| 199 |
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if (jeb->offset + c->sector_size < ofs + sizeof(node)) {
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| 200 |
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D1(printk(KERN_DEBUG "Fewer than %d bytes left to end of block. Not reading\n", sizeof(struct jffs2_unknown_node)));
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| 201 |
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DIRTY_SPACE((jeb->offset + c->sector_size)-ofs);
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| 202 |
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break;
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| 203 |
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}
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| 204 |
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| 205 |
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err = c->mtd->read(c->mtd, ofs, sizeof(node), &retlen, (char *)&node);
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| 206 |
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| 207 |
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if (err) {
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| 208 |
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D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", sizeof(node), ofs, err));
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| 209 |
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return err;
|
| 210 |
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}
|
| 211 |
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if (retlen < sizeof(node)) {
|
| 212 |
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D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%x bytes\n", ofs, retlen));
|
| 213 |
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DIRTY_SPACE(retlen);
|
| 214 |
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ofs += retlen;
|
| 215 |
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continue;
|
| 216 |
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}
|
| 217 |
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|
| 218 |
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if (node.magic == JFFS2_EMPTY_BITMASK && node.nodetype == JFFS2_EMPTY_BITMASK) {
|
| 219 |
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D1(printk(KERN_DEBUG "Found empty flash at 0x%x\n", ofs));
|
| 220 |
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err = jffs2_scan_empty(c, jeb, &ofs, &noise);
|
| 221 |
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if (err) return err;
|
| 222 |
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continue;
|
| 223 |
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}
|
| 224 |
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|
| 225 |
|
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if (ofs == jeb->offset && node.magic == KSAMTIB_CIGAM_2SFFJ) {
|
| 226 |
|
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printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
|
| 227 |
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DIRTY_SPACE(4);
|
| 228 |
|
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ofs += 4;
|
| 229 |
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continue;
|
| 230 |
|
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}
|
| 231 |
|
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if (node.magic == JFFS2_DIRTY_BITMASK) {
|
| 232 |
|
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D1(printk(KERN_DEBUG "Empty bitmask at 0x%08x\n", ofs));
|
| 233 |
|
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DIRTY_SPACE(4);
|
| 234 |
|
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ofs += 4;
|
| 235 |
|
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continue;
|
| 236 |
|
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}
|
| 237 |
|
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if (node.magic == JFFS2_OLD_MAGIC_BITMASK) {
|
| 238 |
|
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printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
|
| 239 |
|
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printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
|
| 240 |
|
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DIRTY_SPACE(4);
|
| 241 |
|
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ofs += 4;
|
| 242 |
|
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continue;
|
| 243 |
|
|
}
|
| 244 |
|
|
if (node.magic != JFFS2_MAGIC_BITMASK) {
|
| 245 |
|
|
/* OK. We're out of possibilities. Whinge and move on */
|
| 246 |
|
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noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n", JFFS2_MAGIC_BITMASK, ofs, node.magic);
|
| 247 |
|
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DIRTY_SPACE(4);
|
| 248 |
|
|
ofs += 4;
|
| 249 |
|
|
continue;
|
| 250 |
|
|
}
|
| 251 |
|
|
/* We seem to have a node of sorts. Check the CRC */
|
| 252 |
|
|
nodetype = node.nodetype;
|
| 253 |
|
|
node.nodetype |= JFFS2_NODE_ACCURATE;
|
| 254 |
|
|
hdr_crc = crc32(0, &node, sizeof(node)-4);
|
| 255 |
|
|
node.nodetype = nodetype;
|
| 256 |
|
|
if (hdr_crc != node.hdr_crc) {
|
| 257 |
|
|
noisy_printk(&noise, "jffs2_scan_eraseblock(): Node at 0x%08x {0x%04x, 0x%04x, 0x%08x) has invalid CRC 0x%08x (calculated 0x%08x)\n",
|
| 258 |
|
|
ofs, node.magic, node.nodetype, node.totlen, node.hdr_crc, hdr_crc);
|
| 259 |
|
|
DIRTY_SPACE(4);
|
| 260 |
|
|
ofs += 4;
|
| 261 |
|
|
continue;
|
| 262 |
|
|
}
|
| 263 |
|
|
|
| 264 |
|
|
if (ofs + node.totlen > jeb->offset + c->sector_size) {
|
| 265 |
|
|
/* Eep. Node goes over the end of the erase block. */
|
| 266 |
|
|
printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
|
| 267 |
|
|
ofs, node.totlen);
|
| 268 |
|
|
printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
|
| 269 |
|
|
DIRTY_SPACE(4);
|
| 270 |
|
|
ofs += 4;
|
| 271 |
|
|
continue;
|
| 272 |
|
|
}
|
| 273 |
|
|
|
| 274 |
|
|
switch(node.nodetype | JFFS2_NODE_ACCURATE) {
|
| 275 |
|
|
case JFFS2_NODETYPE_INODE:
|
| 276 |
|
|
err = jffs2_scan_inode_node(c, jeb, &ofs);
|
| 277 |
|
|
if (err) return err;
|
| 278 |
|
|
break;
|
| 279 |
|
|
|
| 280 |
|
|
case JFFS2_NODETYPE_DIRENT:
|
| 281 |
|
|
err = jffs2_scan_dirent_node(c, jeb, &ofs);
|
| 282 |
|
|
if (err) return err;
|
| 283 |
|
|
break;
|
| 284 |
|
|
|
| 285 |
|
|
case JFFS2_NODETYPE_CLEANMARKER:
|
| 286 |
|
|
if (node.totlen != sizeof(struct jffs2_unknown_node)) {
|
| 287 |
|
|
printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n",
|
| 288 |
|
|
ofs, node.totlen, sizeof(struct jffs2_unknown_node));
|
| 289 |
|
|
DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
|
| 290 |
|
|
} else if (jeb->first_node) {
|
| 291 |
|
|
printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
|
| 292 |
|
|
DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
|
| 293 |
|
|
ofs += PAD(sizeof(struct jffs2_unknown_node));
|
| 294 |
|
|
continue;
|
| 295 |
|
|
} else {
|
| 296 |
|
|
struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref();
|
| 297 |
|
|
if (!marker_ref) {
|
| 298 |
|
|
printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n");
|
| 299 |
|
|
return -ENOMEM;
|
| 300 |
|
|
}
|
| 301 |
|
|
marker_ref->next_in_ino = NULL;
|
| 302 |
|
|
marker_ref->next_phys = NULL;
|
| 303 |
|
|
marker_ref->flash_offset = ofs;
|
| 304 |
|
|
marker_ref->totlen = sizeof(struct jffs2_unknown_node);
|
| 305 |
|
|
jeb->first_node = jeb->last_node = marker_ref;
|
| 306 |
|
|
|
| 307 |
|
|
USED_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
|
| 308 |
|
|
}
|
| 309 |
|
|
ofs += PAD(sizeof(struct jffs2_unknown_node));
|
| 310 |
|
|
break;
|
| 311 |
|
|
|
| 312 |
|
|
default:
|
| 313 |
|
|
switch (node.nodetype & JFFS2_COMPAT_MASK) {
|
| 314 |
|
|
case JFFS2_FEATURE_ROCOMPAT:
|
| 315 |
|
|
printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", node.nodetype, ofs);
|
| 316 |
|
|
c->flags |= JFFS2_SB_FLAG_RO;
|
| 317 |
|
|
if (!(OFNI_BS_2SFFJ(c)->s_flags & MS_RDONLY))
|
| 318 |
|
|
return -EROFS;
|
| 319 |
|
|
DIRTY_SPACE(PAD(node.totlen));
|
| 320 |
|
|
ofs += PAD(node.totlen);
|
| 321 |
|
|
continue;
|
| 322 |
|
|
|
| 323 |
|
|
case JFFS2_FEATURE_INCOMPAT:
|
| 324 |
|
|
printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", node.nodetype, ofs);
|
| 325 |
|
|
return -EINVAL;
|
| 326 |
|
|
|
| 327 |
|
|
case JFFS2_FEATURE_RWCOMPAT_DELETE:
|
| 328 |
|
|
printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", node.nodetype, ofs);
|
| 329 |
|
|
DIRTY_SPACE(PAD(node.totlen));
|
| 330 |
|
|
ofs += PAD(node.totlen);
|
| 331 |
|
|
break;
|
| 332 |
|
|
|
| 333 |
|
|
case JFFS2_FEATURE_RWCOMPAT_COPY:
|
| 334 |
|
|
printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", node.nodetype, ofs);
|
| 335 |
|
|
USED_SPACE(PAD(node.totlen));
|
| 336 |
|
|
ofs += PAD(node.totlen);
|
| 337 |
|
|
break;
|
| 338 |
|
|
}
|
| 339 |
|
|
}
|
| 340 |
|
|
}
|
| 341 |
|
|
D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, used 0x%08x\n", jeb->offset,
|
| 342 |
|
|
jeb->free_size, jeb->dirty_size, jeb->used_size));
|
| 343 |
|
|
return 0;
|
| 344 |
|
|
}
|
| 345 |
|
|
|
| 346 |
|
|
/* We're pointing at the first empty word on the flash. Scan and account for the whole dirty region */
|
| 347 |
|
|
static int jffs2_scan_empty(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, __u32 *startofs, int *noise)
|
| 348 |
|
|
{
|
| 349 |
|
|
__u32 *buf;
|
| 350 |
|
|
__u32 scanlen = (jeb->offset + c->sector_size) - *startofs;
|
| 351 |
|
|
__u32 curofs = *startofs;
|
| 352 |
|
|
|
| 353 |
|
|
buf = kmalloc(min((__u32)PAGE_SIZE, scanlen), GFP_KERNEL);
|
| 354 |
|
|
if (!buf) {
|
| 355 |
|
|
printk(KERN_WARNING "Scan buffer allocation failed\n");
|
| 356 |
|
|
return -ENOMEM;
|
| 357 |
|
|
}
|
| 358 |
|
|
while(scanlen) {
|
| 359 |
|
|
ssize_t retlen;
|
| 360 |
|
|
int ret, i;
|
| 361 |
|
|
|
| 362 |
|
|
ret = c->mtd->read(c->mtd, curofs, min((__u32)PAGE_SIZE, scanlen), &retlen, (char *)buf);
|
| 363 |
|
|
if(ret) {
|
| 364 |
|
|
D1(printk(KERN_WARNING "jffs2_scan_empty(): Read 0x%x bytes at 0x%08x returned %d\n", min((__u32)PAGE_SIZE, scanlen), curofs, ret));
|
| 365 |
|
|
kfree(buf);
|
| 366 |
|
|
return ret;
|
| 367 |
|
|
}
|
| 368 |
|
|
if (retlen < 4) {
|
| 369 |
|
|
D1(printk(KERN_WARNING "Eep. too few bytes read in scan_empty()\n"));
|
| 370 |
|
|
kfree(buf);
|
| 371 |
|
|
return -EIO;
|
| 372 |
|
|
}
|
| 373 |
|
|
for (i=0; i<(retlen / 4); i++) {
|
| 374 |
|
|
if (buf[i] != 0xffffffff) {
|
| 375 |
|
|
curofs += i*4;
|
| 376 |
|
|
|
| 377 |
|
|
noisy_printk(noise, "jffs2_scan_empty(): Empty block at 0x%08x ends at 0x%08x (with 0x%08x)! Marking dirty\n", *startofs, curofs, buf[i]);
|
| 378 |
|
|
DIRTY_SPACE(curofs - (*startofs));
|
| 379 |
|
|
*startofs = curofs;
|
| 380 |
|
|
kfree(buf);
|
| 381 |
|
|
return 0;
|
| 382 |
|
|
}
|
| 383 |
|
|
}
|
| 384 |
|
|
scanlen -= retlen&~3;
|
| 385 |
|
|
curofs += retlen&~3;
|
| 386 |
|
|
}
|
| 387 |
|
|
|
| 388 |
|
|
D1(printk(KERN_DEBUG "Empty flash detected from 0x%08x to 0x%08x\n", *startofs, curofs));
|
| 389 |
|
|
kfree(buf);
|
| 390 |
|
|
*startofs = curofs;
|
| 391 |
|
|
return 0;
|
| 392 |
|
|
}
|
| 393 |
|
|
|
| 394 |
|
|
static struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, __u32 ino)
|
| 395 |
|
|
{
|
| 396 |
|
|
struct jffs2_inode_cache *ic;
|
| 397 |
|
|
|
| 398 |
|
|
ic = jffs2_get_ino_cache(c, ino);
|
| 399 |
|
|
if (ic)
|
| 400 |
|
|
return ic;
|
| 401 |
|
|
|
| 402 |
|
|
ic = jffs2_alloc_inode_cache();
|
| 403 |
|
|
if (!ic) {
|
| 404 |
|
|
printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n");
|
| 405 |
|
|
return NULL;
|
| 406 |
|
|
}
|
| 407 |
|
|
memset(ic, 0, sizeof(*ic));
|
| 408 |
|
|
ic->scan = kmalloc(sizeof(struct jffs2_scan_info), GFP_KERNEL);
|
| 409 |
|
|
if (!ic->scan) {
|
| 410 |
|
|
printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of scan info for inode cache failed\n");
|
| 411 |
|
|
jffs2_free_inode_cache(ic);
|
| 412 |
|
|
return NULL;
|
| 413 |
|
|
}
|
| 414 |
|
|
memset(ic->scan, 0, sizeof(*ic->scan));
|
| 415 |
|
|
ic->ino = ino;
|
| 416 |
|
|
ic->nodes = (void *)ic;
|
| 417 |
|
|
jffs2_add_ino_cache(c, ic);
|
| 418 |
|
|
if (ino == 1)
|
| 419 |
|
|
ic->nlink=1;
|
| 420 |
|
|
return ic;
|
| 421 |
|
|
}
|
| 422 |
|
|
|
| 423 |
|
|
static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, __u32 *ofs)
|
| 424 |
|
|
{
|
| 425 |
|
|
struct jffs2_raw_node_ref *raw;
|
| 426 |
|
|
struct jffs2_full_dnode *fn;
|
| 427 |
|
|
struct jffs2_tmp_dnode_info *tn, **tn_list;
|
| 428 |
|
|
struct jffs2_inode_cache *ic;
|
| 429 |
|
|
struct jffs2_raw_inode ri;
|
| 430 |
|
|
__u32 crc;
|
| 431 |
|
|
__u16 oldnodetype;
|
| 432 |
|
|
int ret;
|
| 433 |
|
|
ssize_t retlen;
|
| 434 |
|
|
|
| 435 |
|
|
D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", *ofs));
|
| 436 |
|
|
|
| 437 |
|
|
ret = c->mtd->read(c->mtd, *ofs, sizeof(ri), &retlen, (char *)&ri);
|
| 438 |
|
|
if (ret) {
|
| 439 |
|
|
printk(KERN_NOTICE "jffs2_scan_inode_node(): Read error at 0x%08x: %d\n", *ofs, ret);
|
| 440 |
|
|
return ret;
|
| 441 |
|
|
}
|
| 442 |
|
|
if (retlen != sizeof(ri)) {
|
| 443 |
|
|
printk(KERN_NOTICE "Short read: 0x%x bytes at 0x%08x instead of requested %x\n",
|
| 444 |
|
|
retlen, *ofs, sizeof(ri));
|
| 445 |
|
|
return -EIO;
|
| 446 |
|
|
}
|
| 447 |
|
|
|
| 448 |
|
|
/* We sort of assume that the node was accurate when it was
|
| 449 |
|
|
first written to the medium :) */
|
| 450 |
|
|
oldnodetype = ri.nodetype;
|
| 451 |
|
|
ri.nodetype |= JFFS2_NODE_ACCURATE;
|
| 452 |
|
|
crc = crc32(0, &ri, sizeof(ri)-8);
|
| 453 |
|
|
ri.nodetype = oldnodetype;
|
| 454 |
|
|
|
| 455 |
|
|
if(crc != ri.node_crc) {
|
| 456 |
|
|
printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
|
| 457 |
|
|
*ofs, ri.node_crc, crc);
|
| 458 |
|
|
/* FIXME: Why do we believe totlen? */
|
| 459 |
|
|
DIRTY_SPACE(4);
|
| 460 |
|
|
*ofs += 4;
|
| 461 |
|
|
return 0;
|
| 462 |
|
|
}
|
| 463 |
|
|
/* There was a bug where we wrote hole nodes out with csize/dsize
|
| 464 |
|
|
swapped. Deal with it */
|
| 465 |
|
|
if (ri.compr == JFFS2_COMPR_ZERO && !ri.dsize && ri.csize) {
|
| 466 |
|
|
ri.dsize = ri.csize;
|
| 467 |
|
|
ri.csize = 0;
|
| 468 |
|
|
}
|
| 469 |
|
|
|
| 470 |
|
|
if (ri.csize) {
|
| 471 |
|
|
/* Check data CRC too */
|
| 472 |
|
|
unsigned char *dbuf;
|
| 473 |
|
|
__u32 crc;
|
| 474 |
|
|
|
| 475 |
|
|
dbuf = kmalloc(PAGE_CACHE_SIZE, GFP_KERNEL);
|
| 476 |
|
|
if (!dbuf) {
|
| 477 |
|
|
printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of temporary data buffer for CRC check failed\n");
|
| 478 |
|
|
return -ENOMEM;
|
| 479 |
|
|
}
|
| 480 |
|
|
ret = c->mtd->read(c->mtd, *ofs+sizeof(ri), ri.csize, &retlen, dbuf);
|
| 481 |
|
|
if (ret) {
|
| 482 |
|
|
printk(KERN_NOTICE "jffs2_scan_inode_node(): Read error at 0x%08x: %d\n", *ofs+sizeof(ri), ret);
|
| 483 |
|
|
kfree(dbuf);
|
| 484 |
|
|
return ret;
|
| 485 |
|
|
}
|
| 486 |
|
|
if (retlen != ri.csize) {
|
| 487 |
|
|
printk(KERN_NOTICE "Short read: 0x%x bytes at 0x%08x instead of requested %x\n",
|
| 488 |
|
|
retlen, *ofs+ sizeof(ri), ri.csize);
|
| 489 |
|
|
kfree(dbuf);
|
| 490 |
|
|
return -EIO;
|
| 491 |
|
|
}
|
| 492 |
|
|
crc = crc32(0, dbuf, ri.csize);
|
| 493 |
|
|
kfree(dbuf);
|
| 494 |
|
|
if (crc != ri.data_crc) {
|
| 495 |
|
|
printk(KERN_NOTICE "jffs2_scan_inode_node(): Data CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
|
| 496 |
|
|
*ofs, ri.data_crc, crc);
|
| 497 |
|
|
DIRTY_SPACE(PAD(ri.totlen));
|
| 498 |
|
|
*ofs += PAD(ri.totlen);
|
| 499 |
|
|
return 0;
|
| 500 |
|
|
}
|
| 501 |
|
|
}
|
| 502 |
|
|
|
| 503 |
|
|
/* Wheee. It worked */
|
| 504 |
|
|
raw = jffs2_alloc_raw_node_ref();
|
| 505 |
|
|
if (!raw) {
|
| 506 |
|
|
printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n");
|
| 507 |
|
|
return -ENOMEM;
|
| 508 |
|
|
}
|
| 509 |
|
|
tn = jffs2_alloc_tmp_dnode_info();
|
| 510 |
|
|
if (!tn) {
|
| 511 |
|
|
jffs2_free_raw_node_ref(raw);
|
| 512 |
|
|
return -ENOMEM;
|
| 513 |
|
|
}
|
| 514 |
|
|
fn = jffs2_alloc_full_dnode();
|
| 515 |
|
|
if (!fn) {
|
| 516 |
|
|
jffs2_free_tmp_dnode_info(tn);
|
| 517 |
|
|
jffs2_free_raw_node_ref(raw);
|
| 518 |
|
|
return -ENOMEM;
|
| 519 |
|
|
}
|
| 520 |
|
|
ic = jffs2_scan_make_ino_cache(c, ri.ino);
|
| 521 |
|
|
if (!ic) {
|
| 522 |
|
|
jffs2_free_full_dnode(fn);
|
| 523 |
|
|
jffs2_free_tmp_dnode_info(tn);
|
| 524 |
|
|
jffs2_free_raw_node_ref(raw);
|
| 525 |
|
|
return -ENOMEM;
|
| 526 |
|
|
}
|
| 527 |
|
|
|
| 528 |
|
|
/* Build the data structures and file them for later */
|
| 529 |
|
|
raw->flash_offset = *ofs;
|
| 530 |
|
|
raw->totlen = PAD(ri.totlen);
|
| 531 |
|
|
raw->next_phys = NULL;
|
| 532 |
|
|
raw->next_in_ino = ic->nodes;
|
| 533 |
|
|
ic->nodes = raw;
|
| 534 |
|
|
if (!jeb->first_node)
|
| 535 |
|
|
jeb->first_node = raw;
|
| 536 |
|
|
if (jeb->last_node)
|
| 537 |
|
|
jeb->last_node->next_phys = raw;
|
| 538 |
|
|
jeb->last_node = raw;
|
| 539 |
|
|
|
| 540 |
|
|
D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n",
|
| 541 |
|
|
ri.ino, ri.version, ri.offset, ri.offset+ri.dsize));
|
| 542 |
|
|
|
| 543 |
|
|
pseudo_random += ri.version;
|
| 544 |
|
|
|
| 545 |
|
|
for (tn_list = &ic->scan->tmpnodes; *tn_list; tn_list = &((*tn_list)->next)) {
|
| 546 |
|
|
if ((*tn_list)->version < ri.version)
|
| 547 |
|
|
continue;
|
| 548 |
|
|
if ((*tn_list)->version > ri.version)
|
| 549 |
|
|
break;
|
| 550 |
|
|
/* Wheee. We've found another instance of the same version number.
|
| 551 |
|
|
We should obsolete one of them.
|
| 552 |
|
|
*/
|
| 553 |
|
|
D1(printk(KERN_DEBUG "Duplicate version %d found in ino #%u. Previous one is at 0x%08x\n", ri.version, ic->ino, (*tn_list)->fn->raw->flash_offset &~3));
|
| 554 |
|
|
if (!jeb->used_size) {
|
| 555 |
|
|
D1(printk(KERN_DEBUG "No valid nodes yet found in this eraseblock 0x%08x, so obsoleting the new instance at 0x%08x\n",
|
| 556 |
|
|
jeb->offset, raw->flash_offset & ~3));
|
| 557 |
|
|
ri.nodetype &= ~JFFS2_NODE_ACCURATE;
|
| 558 |
|
|
/* Perhaps we could also mark it as such on the medium. Maybe later */
|
| 559 |
|
|
}
|
| 560 |
|
|
break;
|
| 561 |
|
|
}
|
| 562 |
|
|
|
| 563 |
|
|
if (ri.nodetype & JFFS2_NODE_ACCURATE) {
|
| 564 |
|
|
memset(fn,0,sizeof(*fn));
|
| 565 |
|
|
|
| 566 |
|
|
fn->ofs = ri.offset;
|
| 567 |
|
|
fn->size = ri.dsize;
|
| 568 |
|
|
fn->frags = 0;
|
| 569 |
|
|
fn->raw = raw;
|
| 570 |
|
|
|
| 571 |
|
|
tn->next = NULL;
|
| 572 |
|
|
tn->fn = fn;
|
| 573 |
|
|
tn->version = ri.version;
|
| 574 |
|
|
|
| 575 |
|
|
USED_SPACE(PAD(ri.totlen));
|
| 576 |
|
|
jffs2_add_tn_to_list(tn, &ic->scan->tmpnodes);
|
| 577 |
|
|
/* Make sure the one we just added is the _last_ in the list
|
| 578 |
|
|
with this version number, so the older ones get obsoleted */
|
| 579 |
|
|
while (tn->next && tn->next->version == tn->version) {
|
| 580 |
|
|
|
| 581 |
|
|
D1(printk(KERN_DEBUG "Shifting new node at 0x%08x after other node at 0x%08x for version %d in list\n",
|
| 582 |
|
|
fn->raw->flash_offset&~3, tn->next->fn->raw->flash_offset &~3, ri.version));
|
| 583 |
|
|
|
| 584 |
|
|
if(tn->fn != fn)
|
| 585 |
|
|
BUG();
|
| 586 |
|
|
tn->fn = tn->next->fn;
|
| 587 |
|
|
tn->next->fn = fn;
|
| 588 |
|
|
tn = tn->next;
|
| 589 |
|
|
}
|
| 590 |
|
|
} else {
|
| 591 |
|
|
jffs2_free_full_dnode(fn);
|
| 592 |
|
|
jffs2_free_tmp_dnode_info(tn);
|
| 593 |
|
|
raw->flash_offset |= 1;
|
| 594 |
|
|
DIRTY_SPACE(PAD(ri.totlen));
|
| 595 |
|
|
}
|
| 596 |
|
|
*ofs += PAD(ri.totlen);
|
| 597 |
|
|
return 0;
|
| 598 |
|
|
}
|
| 599 |
|
|
|
| 600 |
|
|
static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, __u32 *ofs)
|
| 601 |
|
|
{
|
| 602 |
|
|
struct jffs2_raw_node_ref *raw;
|
| 603 |
|
|
struct jffs2_full_dirent *fd;
|
| 604 |
|
|
struct jffs2_inode_cache *ic;
|
| 605 |
|
|
struct jffs2_raw_dirent rd;
|
| 606 |
|
|
__u16 oldnodetype;
|
| 607 |
|
|
int ret;
|
| 608 |
|
|
__u32 crc;
|
| 609 |
|
|
ssize_t retlen;
|
| 610 |
|
|
|
| 611 |
|
|
D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", *ofs));
|
| 612 |
|
|
|
| 613 |
|
|
ret = c->mtd->read(c->mtd, *ofs, sizeof(rd), &retlen, (char *)&rd);
|
| 614 |
|
|
if (ret) {
|
| 615 |
|
|
printk(KERN_NOTICE "jffs2_scan_dirent_node(): Read error at 0x%08x: %d\n", *ofs, ret);
|
| 616 |
|
|
return ret;
|
| 617 |
|
|
}
|
| 618 |
|
|
if (retlen != sizeof(rd)) {
|
| 619 |
|
|
printk(KERN_NOTICE "Short read: 0x%x bytes at 0x%08x instead of requested %x\n",
|
| 620 |
|
|
retlen, *ofs, sizeof(rd));
|
| 621 |
|
|
return -EIO;
|
| 622 |
|
|
}
|
| 623 |
|
|
|
| 624 |
|
|
/* We sort of assume that the node was accurate when it was
|
| 625 |
|
|
first written to the medium :) */
|
| 626 |
|
|
oldnodetype = rd.nodetype;
|
| 627 |
|
|
rd.nodetype |= JFFS2_NODE_ACCURATE;
|
| 628 |
|
|
crc = crc32(0, &rd, sizeof(rd)-8);
|
| 629 |
|
|
rd.nodetype = oldnodetype;
|
| 630 |
|
|
|
| 631 |
|
|
if (crc != rd.node_crc) {
|
| 632 |
|
|
printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
|
| 633 |
|
|
*ofs, rd.node_crc, crc);
|
| 634 |
|
|
/* FIXME: Why do we believe totlen? */
|
| 635 |
|
|
DIRTY_SPACE(4);
|
| 636 |
|
|
*ofs += 4;
|
| 637 |
|
|
return 0;
|
| 638 |
|
|
}
|
| 639 |
|
|
|
| 640 |
|
|
pseudo_random += rd.version;
|
| 641 |
|
|
|
| 642 |
|
|
fd = jffs2_alloc_full_dirent(rd.nsize+1);
|
| 643 |
|
|
if (!fd) {
|
| 644 |
|
|
return -ENOMEM;
|
| 645 |
|
|
}
|
| 646 |
|
|
ret = c->mtd->read(c->mtd, *ofs + sizeof(rd), rd.nsize, &retlen, &fd->name[0]);
|
| 647 |
|
|
if (ret) {
|
| 648 |
|
|
jffs2_free_full_dirent(fd);
|
| 649 |
|
|
printk(KERN_NOTICE "jffs2_scan_dirent_node(): Read error at 0x%08x: %d\n",
|
| 650 |
|
|
*ofs + sizeof(rd), ret);
|
| 651 |
|
|
return ret;
|
| 652 |
|
|
}
|
| 653 |
|
|
if (retlen != rd.nsize) {
|
| 654 |
|
|
jffs2_free_full_dirent(fd);
|
| 655 |
|
|
printk(KERN_NOTICE "Short read: 0x%x bytes at 0x%08x instead of requested %x\n",
|
| 656 |
|
|
retlen, *ofs + sizeof(rd), rd.nsize);
|
| 657 |
|
|
return -EIO;
|
| 658 |
|
|
}
|
| 659 |
|
|
crc = crc32(0, fd->name, rd.nsize);
|
| 660 |
|
|
if (crc != rd.name_crc) {
|
| 661 |
|
|
printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
|
| 662 |
|
|
*ofs, rd.name_crc, crc);
|
| 663 |
|
|
fd->name[rd.nsize]=0;
|
| 664 |
|
|
D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, rd.ino));
|
| 665 |
|
|
jffs2_free_full_dirent(fd);
|
| 666 |
|
|
/* FIXME: Why do we believe totlen? */
|
| 667 |
|
|
DIRTY_SPACE(PAD(rd.totlen));
|
| 668 |
|
|
*ofs += PAD(rd.totlen);
|
| 669 |
|
|
return 0;
|
| 670 |
|
|
}
|
| 671 |
|
|
raw = jffs2_alloc_raw_node_ref();
|
| 672 |
|
|
if (!raw) {
|
| 673 |
|
|
jffs2_free_full_dirent(fd);
|
| 674 |
|
|
printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n");
|
| 675 |
|
|
return -ENOMEM;
|
| 676 |
|
|
}
|
| 677 |
|
|
ic = jffs2_scan_make_ino_cache(c, rd.pino);
|
| 678 |
|
|
if (!ic) {
|
| 679 |
|
|
jffs2_free_full_dirent(fd);
|
| 680 |
|
|
jffs2_free_raw_node_ref(raw);
|
| 681 |
|
|
return -ENOMEM;
|
| 682 |
|
|
}
|
| 683 |
|
|
|
| 684 |
|
|
raw->totlen = PAD(rd.totlen);
|
| 685 |
|
|
raw->flash_offset = *ofs;
|
| 686 |
|
|
raw->next_phys = NULL;
|
| 687 |
|
|
raw->next_in_ino = ic->nodes;
|
| 688 |
|
|
ic->nodes = raw;
|
| 689 |
|
|
if (!jeb->first_node)
|
| 690 |
|
|
jeb->first_node = raw;
|
| 691 |
|
|
if (jeb->last_node)
|
| 692 |
|
|
jeb->last_node->next_phys = raw;
|
| 693 |
|
|
jeb->last_node = raw;
|
| 694 |
|
|
|
| 695 |
|
|
if (rd.nodetype & JFFS2_NODE_ACCURATE) {
|
| 696 |
|
|
fd->raw = raw;
|
| 697 |
|
|
fd->next = NULL;
|
| 698 |
|
|
fd->version = rd.version;
|
| 699 |
|
|
fd->ino = rd.ino;
|
| 700 |
|
|
fd->name[rd.nsize]=0;
|
| 701 |
|
|
fd->nhash = full_name_hash(fd->name, rd.nsize);
|
| 702 |
|
|
fd->type = rd.type;
|
| 703 |
|
|
|
| 704 |
|
|
USED_SPACE(PAD(rd.totlen));
|
| 705 |
|
|
jffs2_add_fd_to_list(c, fd, &ic->scan->dents);
|
| 706 |
|
|
} else {
|
| 707 |
|
|
raw->flash_offset |= 1;
|
| 708 |
|
|
jffs2_free_full_dirent(fd);
|
| 709 |
|
|
|
| 710 |
|
|
DIRTY_SPACE(PAD(rd.totlen));
|
| 711 |
|
|
}
|
| 712 |
|
|
*ofs += PAD(rd.totlen);
|
| 713 |
|
|
return 0;
|
| 714 |
|
|
}
|
| 715 |
|
|
|
| 716 |
|
|
static int count_list(struct list_head *l)
|
| 717 |
|
|
{
|
| 718 |
|
|
uint32_t count = 0;
|
| 719 |
|
|
struct list_head *tmp;
|
| 720 |
|
|
|
| 721 |
|
|
list_for_each(tmp, l) {
|
| 722 |
|
|
count++;
|
| 723 |
|
|
}
|
| 724 |
|
|
return count;
|
| 725 |
|
|
}
|
| 726 |
|
|
|
| 727 |
|
|
/* Note: This breaks if list_empty(head). I don't care. You
|
| 728 |
|
|
might, if you copy this code and use it elsewhere :) */
|
| 729 |
|
|
static void rotate_list(struct list_head *head, uint32_t count)
|
| 730 |
|
|
{
|
| 731 |
|
|
struct list_head *n = head->next;
|
| 732 |
|
|
|
| 733 |
|
|
list_del(head);
|
| 734 |
|
|
while(count--)
|
| 735 |
|
|
n = n->next;
|
| 736 |
|
|
list_add(head, n);
|
| 737 |
|
|
}
|
| 738 |
|
|
|
| 739 |
|
|
static void jffs2_rotate_lists(struct jffs2_sb_info *c)
|
| 740 |
|
|
{
|
| 741 |
|
|
uint32_t x;
|
| 742 |
|
|
|
| 743 |
|
|
x = count_list(&c->clean_list);
|
| 744 |
|
|
if (x)
|
| 745 |
|
|
rotate_list((&c->clean_list), pseudo_random % x);
|
| 746 |
|
|
|
| 747 |
|
|
x = count_list(&c->dirty_list);
|
| 748 |
|
|
if (x)
|
| 749 |
|
|
rotate_list((&c->dirty_list), pseudo_random % x);
|
| 750 |
|
|
|
| 751 |
|
|
if (c->nr_erasing_blocks)
|
| 752 |
|
|
rotate_list((&c->erase_pending_list), pseudo_random % c->nr_erasing_blocks);
|
| 753 |
|
|
|
| 754 |
|
|
if (c->nr_free_blocks) /* Not that it should ever be zero */
|
| 755 |
|
|
rotate_list((&c->free_list), pseudo_random % c->nr_free_blocks);
|
| 756 |
|
|
}
|
