blob: 3e51dd1da8aa7f271dc1205139d9dc0d658cec52 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * JFFS2 -- Journalling Flash File System, Version 2.
3 *
4 * Copyright (C) 2001-2003 Red Hat, Inc.
5 *
6 * Created by David Woodhouse <dwmw2@infradead.org>
7 *
8 * For licensing information, see the file 'LICENCE' in this directory.
9 *
Artem B. Bityutskiydaba5cc2005-09-30 14:59:17 +010010 * $Id: scan.c,v 1.125 2005/09/30 13:59:13 dedekind Exp $
Linus Torvalds1da177e2005-04-16 15:20:36 -070011 *
12 */
13#include <linux/kernel.h>
14#include <linux/sched.h>
15#include <linux/slab.h>
16#include <linux/mtd/mtd.h>
17#include <linux/pagemap.h>
18#include <linux/crc32.h>
19#include <linux/compiler.h>
20#include "nodelist.h"
Ferenc Havasie631ddb2005-09-07 09:35:26 +010021#include "summary.h"
22#include "debug.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070023
Andrew Victor3be36672005-02-09 09:09:05 +000024#define DEFAULT_EMPTY_SCAN_SIZE 1024
Linus Torvalds1da177e2005-04-16 15:20:36 -070025
Linus Torvalds1da177e2005-04-16 15:20:36 -070026#define noisy_printk(noise, args...) do { \
27 if (*(noise)) { \
28 printk(KERN_NOTICE args); \
29 (*(noise))--; \
30 if (!(*(noise))) { \
31 printk(KERN_NOTICE "Further such events for this erase block will not be printed\n"); \
32 } \
33 } \
34} while(0)
35
36static uint32_t pseudo_random;
37
38static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
Ferenc Havasie631ddb2005-09-07 09:35:26 +010039 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s);
Linus Torvalds1da177e2005-04-16 15:20:36 -070040
Thomas Gleixner182ec4e2005-11-07 11:16:07 +000041/* These helper functions _must_ increase ofs and also do the dirty/used space accounting.
Linus Torvalds1da177e2005-04-16 15:20:36 -070042 * Returning an error will abort the mount - bad checksums etc. should just mark the space
43 * as dirty.
44 */
Thomas Gleixner182ec4e2005-11-07 11:16:07 +000045static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
Ferenc Havasie631ddb2005-09-07 09:35:26 +010046 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s);
Linus Torvalds1da177e2005-04-16 15:20:36 -070047static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
Ferenc Havasie631ddb2005-09-07 09:35:26 +010048 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s);
Linus Torvalds1da177e2005-04-16 15:20:36 -070049
50static inline int min_free(struct jffs2_sb_info *c)
51{
52 uint32_t min = 2 * sizeof(struct jffs2_raw_inode);
Andrew Victor2f82ce12005-02-09 09:24:26 +000053#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
Linus Torvalds1da177e2005-04-16 15:20:36 -070054 if (!jffs2_can_mark_obsolete(c) && min < c->wbuf_pagesize)
55 return c->wbuf_pagesize;
56#endif
57 return min;
58
59}
Andrew Victor3be36672005-02-09 09:09:05 +000060
61static inline uint32_t EMPTY_SCAN_SIZE(uint32_t sector_size) {
62 if (sector_size < DEFAULT_EMPTY_SCAN_SIZE)
63 return sector_size;
64 else
65 return DEFAULT_EMPTY_SCAN_SIZE;
66}
67
Linus Torvalds1da177e2005-04-16 15:20:36 -070068int jffs2_scan_medium(struct jffs2_sb_info *c)
69{
70 int i, ret;
71 uint32_t empty_blocks = 0, bad_blocks = 0;
72 unsigned char *flashbuf = NULL;
73 uint32_t buf_size = 0;
Ferenc Havasie631ddb2005-09-07 09:35:26 +010074 struct jffs2_summary *s = NULL; /* summary info collected by the scan process */
Linus Torvalds1da177e2005-04-16 15:20:36 -070075#ifndef __ECOS
76 size_t pointlen;
77
78 if (c->mtd->point) {
79 ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf);
80 if (!ret && pointlen < c->mtd->size) {
81 /* Don't muck about if it won't let us point to the whole flash */
82 D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen));
83 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
84 flashbuf = NULL;
85 }
86 if (ret)
87 D1(printk(KERN_DEBUG "MTD point failed %d\n", ret));
88 }
89#endif
90 if (!flashbuf) {
91 /* For NAND it's quicker to read a whole eraseblock at a time,
92 apparently */
93 if (jffs2_cleanmarker_oob(c))
94 buf_size = c->sector_size;
95 else
96 buf_size = PAGE_SIZE;
97
98 /* Respect kmalloc limitations */
99 if (buf_size > 128*1024)
100 buf_size = 128*1024;
101
102 D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size));
103 flashbuf = kmalloc(buf_size, GFP_KERNEL);
104 if (!flashbuf)
105 return -ENOMEM;
106 }
107
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100108 if (jffs2_sum_active()) {
109 s = kmalloc(sizeof(struct jffs2_summary), GFP_KERNEL);
110 if (!s) {
111 JFFS2_WARNING("Can't allocate memory for summary\n");
112 return -ENOMEM;
113 }
114 memset(s, 0, sizeof(struct jffs2_summary));
115 }
116
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117 for (i=0; i<c->nr_blocks; i++) {
118 struct jffs2_eraseblock *jeb = &c->blocks[i];
119
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100120 /* reset summary info for next eraseblock scan */
121 jffs2_sum_reset_collected(s);
122
123 ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset),
124 buf_size, s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700125
126 if (ret < 0)
127 goto out;
128
Artem B. Bityutskiye0c8e422005-07-24 16:14:17 +0100129 jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700130
131 /* Now decide which list to put it on */
132 switch(ret) {
133 case BLK_STATE_ALLFF:
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000134 /*
135 * Empty block. Since we can't be sure it
Linus Torvalds1da177e2005-04-16 15:20:36 -0700136 * was entirely erased, we just queue it for erase
137 * again. It will be marked as such when the erase
138 * is complete. Meanwhile we still count it as empty
139 * for later checks.
140 */
141 empty_blocks++;
142 list_add(&jeb->list, &c->erase_pending_list);
143 c->nr_erasing_blocks++;
144 break;
145
146 case BLK_STATE_CLEANMARKER:
147 /* Only a CLEANMARKER node is valid */
148 if (!jeb->dirty_size) {
149 /* It's actually free */
150 list_add(&jeb->list, &c->free_list);
151 c->nr_free_blocks++;
152 } else {
153 /* Dirt */
154 D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset));
155 list_add(&jeb->list, &c->erase_pending_list);
156 c->nr_erasing_blocks++;
157 }
158 break;
159
160 case BLK_STATE_CLEAN:
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100161 /* Full (or almost full) of clean data. Clean list */
162 list_add(&jeb->list, &c->clean_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700163 break;
164
165 case BLK_STATE_PARTDIRTY:
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100166 /* Some data, but not full. Dirty list. */
167 /* We want to remember the block with most free space
168 and stick it in the 'nextblock' position to start writing to it. */
169 if (jeb->free_size > min_free(c) &&
170 (!c->nextblock || c->nextblock->free_size < jeb->free_size)) {
171 /* Better candidate for the next writes to go to */
172 if (c->nextblock) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700173 c->nextblock->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size;
174 c->dirty_size += c->nextblock->free_size + c->nextblock->wasted_size;
175 c->free_size -= c->nextblock->free_size;
176 c->wasted_size -= c->nextblock->wasted_size;
177 c->nextblock->free_size = c->nextblock->wasted_size = 0;
178 if (VERYDIRTY(c, c->nextblock->dirty_size)) {
179 list_add(&c->nextblock->list, &c->very_dirty_list);
180 } else {
181 list_add(&c->nextblock->list, &c->dirty_list);
182 }
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100183 /* deleting summary information of the old nextblock */
184 jffs2_sum_reset_collected(c->summary);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185 }
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100186 /* update collected summary infromation for the current nextblock */
187 jffs2_sum_move_collected(c, s);
188 D1(printk(KERN_DEBUG "jffs2_scan_medium(): new nextblock = 0x%08x\n", jeb->offset));
189 c->nextblock = jeb;
190 } else {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700191 jeb->dirty_size += jeb->free_size + jeb->wasted_size;
192 c->dirty_size += jeb->free_size + jeb->wasted_size;
193 c->free_size -= jeb->free_size;
194 c->wasted_size -= jeb->wasted_size;
195 jeb->free_size = jeb->wasted_size = 0;
196 if (VERYDIRTY(c, jeb->dirty_size)) {
197 list_add(&jeb->list, &c->very_dirty_list);
198 } else {
199 list_add(&jeb->list, &c->dirty_list);
200 }
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100201 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700202 break;
203
204 case BLK_STATE_ALLDIRTY:
205 /* Nothing valid - not even a clean marker. Needs erasing. */
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100206 /* For now we just put it on the erasing list. We'll start the erases later */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700207 D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset));
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100208 list_add(&jeb->list, &c->erase_pending_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700209 c->nr_erasing_blocks++;
210 break;
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100211
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 case BLK_STATE_BADBLOCK:
213 D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset));
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100214 list_add(&jeb->list, &c->bad_list);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215 c->bad_size += c->sector_size;
216 c->free_size -= c->sector_size;
217 bad_blocks++;
218 break;
219 default:
220 printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n");
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100221 BUG();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700222 }
223 }
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100224
225 if (jffs2_sum_active() && s)
226 kfree(s);
227
Linus Torvalds1da177e2005-04-16 15:20:36 -0700228 /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */
229 if (c->nextblock && (c->nextblock->dirty_size)) {
230 c->nextblock->wasted_size += c->nextblock->dirty_size;
231 c->wasted_size += c->nextblock->dirty_size;
232 c->dirty_size -= c->nextblock->dirty_size;
233 c->nextblock->dirty_size = 0;
234 }
Andrew Victor2f82ce12005-02-09 09:24:26 +0000235#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
Artem B. Bityutskiydaba5cc2005-09-30 14:59:17 +0100236 if (!jffs2_can_mark_obsolete(c) && c->nextblock && (c->nextblock->free_size % c->wbuf_pagesize)) {
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000237 /* If we're going to start writing into a block which already
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 contains data, and the end of the data isn't page-aligned,
239 skip a little and align it. */
240
Artem B. Bityutskiydaba5cc2005-09-30 14:59:17 +0100241 uint32_t skip = c->nextblock->free_size % c->wbuf_pagesize;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700242
243 D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n",
244 skip));
245 c->nextblock->wasted_size += skip;
246 c->wasted_size += skip;
247
248 c->nextblock->free_size -= skip;
249 c->free_size -= skip;
250 }
251#endif
252 if (c->nr_erasing_blocks) {
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000253 if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700254 printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n");
255 printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks);
256 ret = -EIO;
257 goto out;
258 }
259 jffs2_erase_pending_trigger(c);
260 }
261 ret = 0;
262 out:
263 if (buf_size)
264 kfree(flashbuf);
265#ifndef __ECOS
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000266 else
Linus Torvalds1da177e2005-04-16 15:20:36 -0700267 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
268#endif
269 return ret;
270}
271
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100272int jffs2_fill_scan_buf (struct jffs2_sb_info *c, void *buf,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700273 uint32_t ofs, uint32_t len)
274{
275 int ret;
276 size_t retlen;
277
278 ret = jffs2_flash_read(c, ofs, len, &retlen, buf);
279 if (ret) {
280 D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret));
281 return ret;
282 }
283 if (retlen < len) {
284 D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen));
285 return -EIO;
286 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700287 return 0;
288}
289
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100290int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
291{
292 if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size
293 && (!jeb->first_node || !jeb->first_node->next_phys) )
294 return BLK_STATE_CLEANMARKER;
295
296 /* move blocks with max 4 byte dirty space to cleanlist */
297 else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) {
298 c->dirty_size -= jeb->dirty_size;
299 c->wasted_size += jeb->dirty_size;
300 jeb->wasted_size += jeb->dirty_size;
301 jeb->dirty_size = 0;
302 return BLK_STATE_CLEAN;
303 } else if (jeb->used_size || jeb->unchecked_size)
304 return BLK_STATE_PARTDIRTY;
305 else
306 return BLK_STATE_ALLDIRTY;
307}
308
Linus Torvalds1da177e2005-04-16 15:20:36 -0700309static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100310 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700311 struct jffs2_unknown_node *node;
312 struct jffs2_unknown_node crcnode;
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100313 struct jffs2_sum_marker *sm;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700314 uint32_t ofs, prevofs;
315 uint32_t hdr_crc, buf_ofs, buf_len;
316 int err;
317 int noise = 0;
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100318
319
Andrew Victor2f82ce12005-02-09 09:24:26 +0000320#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
Linus Torvalds1da177e2005-04-16 15:20:36 -0700321 int cleanmarkerfound = 0;
322#endif
323
324 ofs = jeb->offset;
325 prevofs = jeb->offset - 1;
326
327 D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));
328
Andrew Victor2f82ce12005-02-09 09:24:26 +0000329#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
Linus Torvalds1da177e2005-04-16 15:20:36 -0700330 if (jffs2_cleanmarker_oob(c)) {
331 int ret = jffs2_check_nand_cleanmarker(c, jeb);
332 D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret));
333 /* Even if it's not found, we still scan to see
334 if the block is empty. We use this information
335 to decide whether to erase it or not. */
336 switch (ret) {
337 case 0: cleanmarkerfound = 1; break;
338 case 1: break;
339 case 2: return BLK_STATE_BADBLOCK;
340 case 3: return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */
341 default: return ret;
342 }
343 }
344#endif
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100345
346 if (jffs2_sum_active()) {
347 sm = kmalloc(sizeof(struct jffs2_sum_marker), GFP_KERNEL);
348 if (!sm) {
349 return -ENOMEM;
350 }
351
352 err = jffs2_fill_scan_buf(c, (unsigned char *) sm, jeb->offset + c->sector_size -
353 sizeof(struct jffs2_sum_marker), sizeof(struct jffs2_sum_marker));
354 if (err) {
355 kfree(sm);
356 return err;
357 }
358
359 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC ) {
360 err = jffs2_sum_scan_sumnode(c, jeb, je32_to_cpu(sm->offset), &pseudo_random);
361 if (err) {
362 kfree(sm);
363 return err;
364 }
365 }
366
367 kfree(sm);
368
369 ofs = jeb->offset;
370 prevofs = jeb->offset - 1;
371 }
372
Linus Torvalds1da177e2005-04-16 15:20:36 -0700373 buf_ofs = jeb->offset;
374
375 if (!buf_size) {
376 buf_len = c->sector_size;
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100377
378 if (jffs2_sum_active()) {
379 /* must reread because of summary test */
380 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
381 if (err)
382 return err;
383 }
384
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385 } else {
Andrew Victor3be36672005-02-09 09:09:05 +0000386 buf_len = EMPTY_SCAN_SIZE(c->sector_size);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700387 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
388 if (err)
389 return err;
390 }
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000391
Linus Torvalds1da177e2005-04-16 15:20:36 -0700392 /* We temporarily use 'ofs' as a pointer into the buffer/jeb */
393 ofs = 0;
394
395 /* Scan only 4KiB of 0xFF before declaring it's empty */
Andrew Victor3be36672005-02-09 09:09:05 +0000396 while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 ofs += 4;
398
Andrew Victor3be36672005-02-09 09:09:05 +0000399 if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) {
Andrew Victor2f82ce12005-02-09 09:24:26 +0000400#ifdef CONFIG_JFFS2_FS_WRITEBUFFER
Linus Torvalds1da177e2005-04-16 15:20:36 -0700401 if (jffs2_cleanmarker_oob(c)) {
402 /* scan oob, take care of cleanmarker */
403 int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound);
404 D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret));
405 switch (ret) {
406 case 0: return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF;
407 case 1: return BLK_STATE_ALLDIRTY;
408 default: return ret;
409 }
410 }
411#endif
412 D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
Andrew Victor8f15fd52005-02-09 09:17:45 +0000413 if (c->cleanmarker_size == 0)
414 return BLK_STATE_CLEANMARKER; /* don't bother with re-erase */
415 else
416 return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700417 }
418 if (ofs) {
419 D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset,
420 jeb->offset + ofs));
421 DIRTY_SPACE(ofs);
422 }
423
424 /* Now ofs is a complete physical flash offset as it always was... */
425 ofs += jeb->offset;
426
427 noise = 10;
428
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100429 dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset);
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100430
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000431scan_more:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700432 while(ofs < jeb->offset + c->sector_size) {
433
Artem B. Bityutskiye0c8e422005-07-24 16:14:17 +0100434 jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435
436 cond_resched();
437
438 if (ofs & 3) {
439 printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
440 ofs = PAD(ofs);
441 continue;
442 }
443 if (ofs == prevofs) {
444 printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
445 DIRTY_SPACE(4);
446 ofs += 4;
447 continue;
448 }
449 prevofs = ofs;
450
451 if (jeb->offset + c->sector_size < ofs + sizeof(*node)) {
452 D1(printk(KERN_DEBUG "Fewer than %zd bytes left to end of block. (%x+%x<%x+%zx) Not reading\n", sizeof(struct jffs2_unknown_node),
453 jeb->offset, c->sector_size, ofs, sizeof(*node)));
454 DIRTY_SPACE((jeb->offset + c->sector_size)-ofs);
455 break;
456 }
457
458 if (buf_ofs + buf_len < ofs + sizeof(*node)) {
459 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
460 D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n",
461 sizeof(struct jffs2_unknown_node), buf_len, ofs));
462 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
463 if (err)
464 return err;
465 buf_ofs = ofs;
466 }
467
468 node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs];
469
470 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
471 uint32_t inbuf_ofs;
472 uint32_t empty_start;
473
474 empty_start = ofs;
475 ofs += 4;
476
477 D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs));
478 more_empty:
479 inbuf_ofs = ofs - buf_ofs;
480 while (inbuf_ofs < buf_len) {
481 if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) {
482 printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n",
483 empty_start, ofs);
484 DIRTY_SPACE(ofs-empty_start);
485 goto scan_more;
486 }
487
488 inbuf_ofs+=4;
489 ofs += 4;
490 }
491 /* Ran off end. */
492 D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs));
493
494 /* If we're only checking the beginning of a block with a cleanmarker,
495 bail now */
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000496 if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) &&
Artem B. Bityuckiyb81226c2005-02-17 17:51:17 +0000497 c->cleanmarker_size && !jeb->dirty_size && !jeb->first_node->next_phys) {
Andrew Victor3be36672005-02-09 09:09:05 +0000498 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size)));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700499 return BLK_STATE_CLEANMARKER;
500 }
501
502 /* See how much more there is to read in this eraseblock... */
503 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
504 if (!buf_len) {
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000505 /* No more to read. Break out of main loop without marking
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 this range of empty space as dirty (because it's not) */
507 D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n",
508 empty_start));
509 break;
510 }
511 D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs));
512 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
513 if (err)
514 return err;
515 buf_ofs = ofs;
516 goto more_empty;
517 }
518
519 if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) {
520 printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
521 DIRTY_SPACE(4);
522 ofs += 4;
523 continue;
524 }
525 if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) {
526 D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs));
527 DIRTY_SPACE(4);
528 ofs += 4;
529 continue;
530 }
531 if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) {
532 printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
533 printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
534 DIRTY_SPACE(4);
535 ofs += 4;
536 continue;
537 }
538 if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) {
539 /* OK. We're out of possibilities. Whinge and move on */
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000540 noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n",
541 JFFS2_MAGIC_BITMASK, ofs,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700542 je16_to_cpu(node->magic));
543 DIRTY_SPACE(4);
544 ofs += 4;
545 continue;
546 }
547 /* We seem to have a node of sorts. Check the CRC */
548 crcnode.magic = node->magic;
549 crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE);
550 crcnode.totlen = node->totlen;
551 hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4);
552
553 if (hdr_crc != je32_to_cpu(node->hdr_crc)) {
554 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",
555 ofs, je16_to_cpu(node->magic),
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000556 je16_to_cpu(node->nodetype),
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 je32_to_cpu(node->totlen),
558 je32_to_cpu(node->hdr_crc),
559 hdr_crc);
560 DIRTY_SPACE(4);
561 ofs += 4;
562 continue;
563 }
564
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000565 if (ofs + je32_to_cpu(node->totlen) >
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566 jeb->offset + c->sector_size) {
567 /* Eep. Node goes over the end of the erase block. */
568 printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
569 ofs, je32_to_cpu(node->totlen));
570 printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
571 DIRTY_SPACE(4);
572 ofs += 4;
573 continue;
574 }
575
576 if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
577 /* Wheee. This is an obsoleted node */
578 D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs));
579 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
580 ofs += PAD(je32_to_cpu(node->totlen));
581 continue;
582 }
583
584 switch(je16_to_cpu(node->nodetype)) {
585 case JFFS2_NODETYPE_INODE:
586 if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) {
587 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
588 D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n",
589 sizeof(struct jffs2_raw_inode), buf_len, ofs));
590 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
591 if (err)
592 return err;
593 buf_ofs = ofs;
594 node = (void *)buf;
595 }
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100596 err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 if (err) return err;
598 ofs += PAD(je32_to_cpu(node->totlen));
599 break;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000600
Linus Torvalds1da177e2005-04-16 15:20:36 -0700601 case JFFS2_NODETYPE_DIRENT:
602 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
603 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
604 D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n",
605 je32_to_cpu(node->totlen), buf_len, ofs));
606 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
607 if (err)
608 return err;
609 buf_ofs = ofs;
610 node = (void *)buf;
611 }
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100612 err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700613 if (err) return err;
614 ofs += PAD(je32_to_cpu(node->totlen));
615 break;
616
617 case JFFS2_NODETYPE_CLEANMARKER:
618 D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs));
619 if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000620 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700621 ofs, je32_to_cpu(node->totlen), c->cleanmarker_size);
622 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
623 ofs += PAD(sizeof(struct jffs2_unknown_node));
624 } else if (jeb->first_node) {
625 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
626 DIRTY_SPACE(PAD(sizeof(struct jffs2_unknown_node)));
627 ofs += PAD(sizeof(struct jffs2_unknown_node));
628 } else {
629 struct jffs2_raw_node_ref *marker_ref = jffs2_alloc_raw_node_ref();
630 if (!marker_ref) {
631 printk(KERN_NOTICE "Failed to allocate node ref for clean marker\n");
632 return -ENOMEM;
633 }
634 marker_ref->next_in_ino = NULL;
635 marker_ref->next_phys = NULL;
636 marker_ref->flash_offset = ofs | REF_NORMAL;
637 marker_ref->__totlen = c->cleanmarker_size;
638 jeb->first_node = jeb->last_node = marker_ref;
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000639
Linus Torvalds1da177e2005-04-16 15:20:36 -0700640 USED_SPACE(PAD(c->cleanmarker_size));
641 ofs += PAD(c->cleanmarker_size);
642 }
643 break;
644
645 case JFFS2_NODETYPE_PADDING:
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100646 if (jffs2_sum_active())
647 jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700648 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
649 ofs += PAD(je32_to_cpu(node->totlen));
650 break;
651
652 default:
653 switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) {
654 case JFFS2_FEATURE_ROCOMPAT:
655 printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
656 c->flags |= JFFS2_SB_FLAG_RO;
657 if (!(jffs2_is_readonly(c)))
658 return -EROFS;
659 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
660 ofs += PAD(je32_to_cpu(node->totlen));
661 break;
662
663 case JFFS2_FEATURE_INCOMPAT:
664 printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
665 return -EINVAL;
666
667 case JFFS2_FEATURE_RWCOMPAT_DELETE:
668 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
669 DIRTY_SPACE(PAD(je32_to_cpu(node->totlen)));
670 ofs += PAD(je32_to_cpu(node->totlen));
671 break;
672
673 case JFFS2_FEATURE_RWCOMPAT_COPY:
674 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
675 USED_SPACE(PAD(je32_to_cpu(node->totlen)));
676 ofs += PAD(je32_to_cpu(node->totlen));
677 break;
678 }
679 }
680 }
681
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100682 if (jffs2_sum_active()) {
683 if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) {
Artem B. Bityutskiy733802d2005-09-22 12:25:00 +0100684 dbg_summary("There is not enough space for "
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100685 "summary information, disabling for this jeb!\n");
686 jffs2_sum_disable_collecting(s);
687 }
688 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000690 D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x\n", jeb->offset,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691 jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size));
692
693 /* mark_node_obsolete can add to wasted !! */
694 if (jeb->wasted_size) {
695 jeb->dirty_size += jeb->wasted_size;
696 c->dirty_size += jeb->wasted_size;
697 c->wasted_size -= jeb->wasted_size;
698 jeb->wasted_size = 0;
699 }
700
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100701 return jffs2_scan_classify_jeb(c, jeb);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700702}
703
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100704struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700705{
706 struct jffs2_inode_cache *ic;
707
708 ic = jffs2_get_ino_cache(c, ino);
709 if (ic)
710 return ic;
711
712 if (ino > c->highest_ino)
713 c->highest_ino = ino;
714
715 ic = jffs2_alloc_inode_cache();
716 if (!ic) {
717 printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n");
718 return NULL;
719 }
720 memset(ic, 0, sizeof(*ic));
721
722 ic->ino = ino;
723 ic->nodes = (void *)ic;
724 jffs2_add_ino_cache(c, ic);
725 if (ino == 1)
726 ic->nlink = 1;
727 return ic;
728}
729
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000730static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100731 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732{
733 struct jffs2_raw_node_ref *raw;
734 struct jffs2_inode_cache *ic;
735 uint32_t ino = je32_to_cpu(ri->ino);
736
737 D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs));
738
739 /* We do very little here now. Just check the ino# to which we should attribute
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000740 this node; we can do all the CRC checking etc. later. There's a tradeoff here --
Linus Torvalds1da177e2005-04-16 15:20:36 -0700741 we used to scan the flash once only, reading everything we want from it into
742 memory, then building all our in-core data structures and freeing the extra
743 information. Now we allow the first part of the mount to complete a lot quicker,
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000744 but we have to go _back_ to the flash in order to finish the CRC checking, etc.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700745 Which means that the _full_ amount of time to get to proper write mode with GC
746 operational may actually be _longer_ than before. Sucks to be me. */
747
748 raw = jffs2_alloc_raw_node_ref();
749 if (!raw) {
750 printk(KERN_NOTICE "jffs2_scan_inode_node(): allocation of node reference failed\n");
751 return -ENOMEM;
752 }
753
754 ic = jffs2_get_ino_cache(c, ino);
755 if (!ic) {
756 /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the
757 first node we found for this inode. Do a CRC check to protect against the former
758 case */
759 uint32_t crc = crc32(0, ri, sizeof(*ri)-8);
760
761 if (crc != je32_to_cpu(ri->node_crc)) {
762 printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
763 ofs, je32_to_cpu(ri->node_crc), crc);
764 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */
765 DIRTY_SPACE(PAD(je32_to_cpu(ri->totlen)));
766 jffs2_free_raw_node_ref(raw);
767 return 0;
768 }
769 ic = jffs2_scan_make_ino_cache(c, ino);
770 if (!ic) {
771 jffs2_free_raw_node_ref(raw);
772 return -ENOMEM;
773 }
774 }
775
776 /* Wheee. It worked */
777
778 raw->flash_offset = ofs | REF_UNCHECKED;
779 raw->__totlen = PAD(je32_to_cpu(ri->totlen));
780 raw->next_phys = NULL;
781 raw->next_in_ino = ic->nodes;
782
783 ic->nodes = raw;
784 if (!jeb->first_node)
785 jeb->first_node = raw;
786 if (jeb->last_node)
787 jeb->last_node->next_phys = raw;
788 jeb->last_node = raw;
789
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000790 D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n",
Linus Torvalds1da177e2005-04-16 15:20:36 -0700791 je32_to_cpu(ri->ino), je32_to_cpu(ri->version),
792 je32_to_cpu(ri->offset),
793 je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize)));
794
795 pseudo_random += je32_to_cpu(ri->version);
796
797 UNCHECKED_SPACE(PAD(je32_to_cpu(ri->totlen)));
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100798
799 if (jffs2_sum_active()) {
800 jffs2_sum_add_inode_mem(s, ri, ofs - jeb->offset);
801 }
802
Linus Torvalds1da177e2005-04-16 15:20:36 -0700803 return 0;
804}
805
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000806static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100807 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700808{
809 struct jffs2_raw_node_ref *raw;
810 struct jffs2_full_dirent *fd;
811 struct jffs2_inode_cache *ic;
812 uint32_t crc;
813
814 D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs));
815
816 /* We don't get here unless the node is still valid, so we don't have to
817 mask in the ACCURATE bit any more. */
818 crc = crc32(0, rd, sizeof(*rd)-8);
819
820 if (crc != je32_to_cpu(rd->node_crc)) {
821 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
822 ofs, je32_to_cpu(rd->node_crc), crc);
823 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */
824 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen)));
825 return 0;
826 }
827
828 pseudo_random += je32_to_cpu(rd->version);
829
830 fd = jffs2_alloc_full_dirent(rd->nsize+1);
831 if (!fd) {
832 return -ENOMEM;
833 }
834 memcpy(&fd->name, rd->name, rd->nsize);
835 fd->name[rd->nsize] = 0;
836
837 crc = crc32(0, fd->name, rd->nsize);
838 if (crc != je32_to_cpu(rd->name_crc)) {
839 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000840 ofs, je32_to_cpu(rd->name_crc), crc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700841 D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino)));
842 jffs2_free_full_dirent(fd);
843 /* FIXME: Why do we believe totlen? */
844 /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */
845 DIRTY_SPACE(PAD(je32_to_cpu(rd->totlen)));
846 return 0;
847 }
848 raw = jffs2_alloc_raw_node_ref();
849 if (!raw) {
850 jffs2_free_full_dirent(fd);
851 printk(KERN_NOTICE "jffs2_scan_dirent_node(): allocation of node reference failed\n");
852 return -ENOMEM;
853 }
854 ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino));
855 if (!ic) {
856 jffs2_free_full_dirent(fd);
857 jffs2_free_raw_node_ref(raw);
858 return -ENOMEM;
859 }
Thomas Gleixner182ec4e2005-11-07 11:16:07 +0000860
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861 raw->__totlen = PAD(je32_to_cpu(rd->totlen));
862 raw->flash_offset = ofs | REF_PRISTINE;
863 raw->next_phys = NULL;
864 raw->next_in_ino = ic->nodes;
865 ic->nodes = raw;
866 if (!jeb->first_node)
867 jeb->first_node = raw;
868 if (jeb->last_node)
869 jeb->last_node->next_phys = raw;
870 jeb->last_node = raw;
871
872 fd->raw = raw;
873 fd->next = NULL;
874 fd->version = je32_to_cpu(rd->version);
875 fd->ino = je32_to_cpu(rd->ino);
876 fd->nhash = full_name_hash(fd->name, rd->nsize);
877 fd->type = rd->type;
878 USED_SPACE(PAD(je32_to_cpu(rd->totlen)));
879 jffs2_add_fd_to_list(c, fd, &ic->scan_dents);
880
Ferenc Havasie631ddb2005-09-07 09:35:26 +0100881 if (jffs2_sum_active()) {
882 jffs2_sum_add_dirent_mem(s, rd, ofs - jeb->offset);
883 }
884
Linus Torvalds1da177e2005-04-16 15:20:36 -0700885 return 0;
886}
887
888static int count_list(struct list_head *l)
889{
890 uint32_t count = 0;
891 struct list_head *tmp;
892
893 list_for_each(tmp, l) {
894 count++;
895 }
896 return count;
897}
898
899/* Note: This breaks if list_empty(head). I don't care. You
900 might, if you copy this code and use it elsewhere :) */
901static void rotate_list(struct list_head *head, uint32_t count)
902{
903 struct list_head *n = head->next;
904
905 list_del(head);
906 while(count--) {
907 n = n->next;
908 }
909 list_add(head, n);
910}
911
912void jffs2_rotate_lists(struct jffs2_sb_info *c)
913{
914 uint32_t x;
915 uint32_t rotateby;
916
917 x = count_list(&c->clean_list);
918 if (x) {
919 rotateby = pseudo_random % x;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700920 rotate_list((&c->clean_list), rotateby);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700921 }
922
923 x = count_list(&c->very_dirty_list);
924 if (x) {
925 rotateby = pseudo_random % x;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 rotate_list((&c->very_dirty_list), rotateby);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700927 }
928
929 x = count_list(&c->dirty_list);
930 if (x) {
931 rotateby = pseudo_random % x;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700932 rotate_list((&c->dirty_list), rotateby);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700933 }
934
935 x = count_list(&c->erasable_list);
936 if (x) {
937 rotateby = pseudo_random % x;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700938 rotate_list((&c->erasable_list), rotateby);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700939 }
940
941 if (c->nr_erasing_blocks) {
942 rotateby = pseudo_random % c->nr_erasing_blocks;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943 rotate_list((&c->erase_pending_list), rotateby);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700944 }
945
946 if (c->nr_free_blocks) {
947 rotateby = pseudo_random % c->nr_free_blocks;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700948 rotate_list((&c->free_list), rotateby);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700949 }
950}