ia64/linux-2.6.18-xen.hg

view fs/jffs2/scan.c @ 524:7f8b544237bf

netfront: Allow netfront in domain 0.

This is useful if your physical network device is in a utility domain.

Signed-off-by: Ian Campbell <ian.campbell@citrix.com>
author Keir Fraser <keir.fraser@citrix.com>
date Tue Apr 15 15:18:58 2008 +0100 (2008-04-15)
parents 831230e53067
children
line source
1 /*
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 *
10 * $Id: scan.c,v 1.125 2005/09/30 13:59:13 dedekind Exp $
11 *
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"
21 #include "summary.h"
22 #include "debug.h"
24 #define DEFAULT_EMPTY_SCAN_SIZE 1024
26 #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)
36 static uint32_t pseudo_random;
38 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
39 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s);
41 /* These helper functions _must_ increase ofs and also do the dirty/used space accounting.
42 * Returning an error will abort the mount - bad checksums etc. should just mark the space
43 * as dirty.
44 */
45 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
46 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s);
47 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
48 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s);
50 static inline int min_free(struct jffs2_sb_info *c)
51 {
52 uint32_t min = 2 * sizeof(struct jffs2_raw_inode);
53 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
54 if (!jffs2_can_mark_obsolete(c) && min < c->wbuf_pagesize)
55 return c->wbuf_pagesize;
56 #endif
57 return min;
59 }
61 static 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 }
68 static int file_dirty(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
69 {
70 int ret;
72 if ((ret = jffs2_prealloc_raw_node_refs(c, jeb, 1)))
73 return ret;
74 if ((ret = jffs2_scan_dirty_space(c, jeb, jeb->free_size)))
75 return ret;
76 /* Turned wasted size into dirty, since we apparently
77 think it's recoverable now. */
78 jeb->dirty_size += jeb->wasted_size;
79 c->dirty_size += jeb->wasted_size;
80 c->wasted_size -= jeb->wasted_size;
81 jeb->wasted_size = 0;
82 if (VERYDIRTY(c, jeb->dirty_size)) {
83 list_add(&jeb->list, &c->very_dirty_list);
84 } else {
85 list_add(&jeb->list, &c->dirty_list);
86 }
87 return 0;
88 }
90 int jffs2_scan_medium(struct jffs2_sb_info *c)
91 {
92 int i, ret;
93 uint32_t empty_blocks = 0, bad_blocks = 0;
94 unsigned char *flashbuf = NULL;
95 uint32_t buf_size = 0;
96 struct jffs2_summary *s = NULL; /* summary info collected by the scan process */
97 #ifndef __ECOS
98 size_t pointlen;
100 if (c->mtd->point) {
101 ret = c->mtd->point (c->mtd, 0, c->mtd->size, &pointlen, &flashbuf);
102 if (!ret && pointlen < c->mtd->size) {
103 /* Don't muck about if it won't let us point to the whole flash */
104 D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", pointlen));
105 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
106 flashbuf = NULL;
107 }
108 if (ret)
109 D1(printk(KERN_DEBUG "MTD point failed %d\n", ret));
110 }
111 #endif
112 if (!flashbuf) {
113 /* For NAND it's quicker to read a whole eraseblock at a time,
114 apparently */
115 if (jffs2_cleanmarker_oob(c))
116 buf_size = c->sector_size;
117 else
118 buf_size = PAGE_SIZE;
120 /* Respect kmalloc limitations */
121 if (buf_size > 128*1024)
122 buf_size = 128*1024;
124 D1(printk(KERN_DEBUG "Allocating readbuf of %d bytes\n", buf_size));
125 flashbuf = kmalloc(buf_size, GFP_KERNEL);
126 if (!flashbuf)
127 return -ENOMEM;
128 }
130 if (jffs2_sum_active()) {
131 s = kmalloc(sizeof(struct jffs2_summary), GFP_KERNEL);
132 if (!s) {
133 JFFS2_WARNING("Can't allocate memory for summary\n");
134 return -ENOMEM;
135 }
136 memset(s, 0, sizeof(struct jffs2_summary));
137 }
139 for (i=0; i<c->nr_blocks; i++) {
140 struct jffs2_eraseblock *jeb = &c->blocks[i];
142 /* reset summary info for next eraseblock scan */
143 jffs2_sum_reset_collected(s);
145 ret = jffs2_scan_eraseblock(c, jeb, buf_size?flashbuf:(flashbuf+jeb->offset),
146 buf_size, s);
148 if (ret < 0)
149 goto out;
151 jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
153 /* Now decide which list to put it on */
154 switch(ret) {
155 case BLK_STATE_ALLFF:
156 /*
157 * Empty block. Since we can't be sure it
158 * was entirely erased, we just queue it for erase
159 * again. It will be marked as such when the erase
160 * is complete. Meanwhile we still count it as empty
161 * for later checks.
162 */
163 empty_blocks++;
164 list_add(&jeb->list, &c->erase_pending_list);
165 c->nr_erasing_blocks++;
166 break;
168 case BLK_STATE_CLEANMARKER:
169 /* Only a CLEANMARKER node is valid */
170 if (!jeb->dirty_size) {
171 /* It's actually free */
172 list_add(&jeb->list, &c->free_list);
173 c->nr_free_blocks++;
174 } else {
175 /* Dirt */
176 D1(printk(KERN_DEBUG "Adding all-dirty block at 0x%08x to erase_pending_list\n", jeb->offset));
177 list_add(&jeb->list, &c->erase_pending_list);
178 c->nr_erasing_blocks++;
179 }
180 break;
182 case BLK_STATE_CLEAN:
183 /* Full (or almost full) of clean data. Clean list */
184 list_add(&jeb->list, &c->clean_list);
185 break;
187 case BLK_STATE_PARTDIRTY:
188 /* Some data, but not full. Dirty list. */
189 /* We want to remember the block with most free space
190 and stick it in the 'nextblock' position to start writing to it. */
191 if (jeb->free_size > min_free(c) &&
192 (!c->nextblock || c->nextblock->free_size < jeb->free_size)) {
193 /* Better candidate for the next writes to go to */
194 if (c->nextblock) {
195 ret = file_dirty(c, c->nextblock);
196 if (ret)
197 return ret;
198 /* deleting summary information of the old nextblock */
199 jffs2_sum_reset_collected(c->summary);
200 }
201 /* update collected summary information for the current nextblock */
202 jffs2_sum_move_collected(c, s);
203 D1(printk(KERN_DEBUG "jffs2_scan_medium(): new nextblock = 0x%08x\n", jeb->offset));
204 c->nextblock = jeb;
205 } else {
206 ret = file_dirty(c, jeb);
207 if (ret)
208 return ret;
209 }
210 break;
212 case BLK_STATE_ALLDIRTY:
213 /* Nothing valid - not even a clean marker. Needs erasing. */
214 /* For now we just put it on the erasing list. We'll start the erases later */
215 D1(printk(KERN_NOTICE "JFFS2: Erase block at 0x%08x is not formatted. It will be erased\n", jeb->offset));
216 list_add(&jeb->list, &c->erase_pending_list);
217 c->nr_erasing_blocks++;
218 break;
220 case BLK_STATE_BADBLOCK:
221 D1(printk(KERN_NOTICE "JFFS2: Block at 0x%08x is bad\n", jeb->offset));
222 list_add(&jeb->list, &c->bad_list);
223 c->bad_size += c->sector_size;
224 c->free_size -= c->sector_size;
225 bad_blocks++;
226 break;
227 default:
228 printk(KERN_WARNING "jffs2_scan_medium(): unknown block state\n");
229 BUG();
230 }
231 }
233 /* Nextblock dirty is always seen as wasted, because we cannot recycle it now */
234 if (c->nextblock && (c->nextblock->dirty_size)) {
235 c->nextblock->wasted_size += c->nextblock->dirty_size;
236 c->wasted_size += c->nextblock->dirty_size;
237 c->dirty_size -= c->nextblock->dirty_size;
238 c->nextblock->dirty_size = 0;
239 }
240 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
241 if (!jffs2_can_mark_obsolete(c) && c->wbuf_pagesize && c->nextblock && (c->nextblock->free_size % c->wbuf_pagesize)) {
242 /* If we're going to start writing into a block which already
243 contains data, and the end of the data isn't page-aligned,
244 skip a little and align it. */
246 uint32_t skip = c->nextblock->free_size % c->wbuf_pagesize;
248 D1(printk(KERN_DEBUG "jffs2_scan_medium(): Skipping %d bytes in nextblock to ensure page alignment\n",
249 skip));
250 jffs2_prealloc_raw_node_refs(c, c->nextblock, 1);
251 jffs2_scan_dirty_space(c, c->nextblock, skip);
252 }
253 #endif
254 if (c->nr_erasing_blocks) {
255 if ( !c->used_size && ((c->nr_free_blocks+empty_blocks+bad_blocks)!= c->nr_blocks || bad_blocks == c->nr_blocks) ) {
256 printk(KERN_NOTICE "Cowardly refusing to erase blocks on filesystem with no valid JFFS2 nodes\n");
257 printk(KERN_NOTICE "empty_blocks %d, bad_blocks %d, c->nr_blocks %d\n",empty_blocks,bad_blocks,c->nr_blocks);
258 ret = -EIO;
259 goto out;
260 }
261 jffs2_erase_pending_trigger(c);
262 }
263 ret = 0;
264 out:
265 if (buf_size)
266 kfree(flashbuf);
267 #ifndef __ECOS
268 else
269 c->mtd->unpoint(c->mtd, flashbuf, 0, c->mtd->size);
270 #endif
271 if (s)
272 kfree(s);
274 return ret;
275 }
277 static int jffs2_fill_scan_buf(struct jffs2_sb_info *c, void *buf,
278 uint32_t ofs, uint32_t len)
279 {
280 int ret;
281 size_t retlen;
283 ret = jffs2_flash_read(c, ofs, len, &retlen, buf);
284 if (ret) {
285 D1(printk(KERN_WARNING "mtd->read(0x%x bytes from 0x%x) returned %d\n", len, ofs, ret));
286 return ret;
287 }
288 if (retlen < len) {
289 D1(printk(KERN_WARNING "Read at 0x%x gave only 0x%zx bytes\n", ofs, retlen));
290 return -EIO;
291 }
292 return 0;
293 }
295 int jffs2_scan_classify_jeb(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
296 {
297 if ((jeb->used_size + jeb->unchecked_size) == PAD(c->cleanmarker_size) && !jeb->dirty_size
298 && (!jeb->first_node || !ref_next(jeb->first_node)) )
299 return BLK_STATE_CLEANMARKER;
301 /* move blocks with max 4 byte dirty space to cleanlist */
302 else if (!ISDIRTY(c->sector_size - (jeb->used_size + jeb->unchecked_size))) {
303 c->dirty_size -= jeb->dirty_size;
304 c->wasted_size += jeb->dirty_size;
305 jeb->wasted_size += jeb->dirty_size;
306 jeb->dirty_size = 0;
307 return BLK_STATE_CLEAN;
308 } else if (jeb->used_size || jeb->unchecked_size)
309 return BLK_STATE_PARTDIRTY;
310 else
311 return BLK_STATE_ALLDIRTY;
312 }
314 #ifdef CONFIG_JFFS2_FS_XATTR
315 static int jffs2_scan_xattr_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
316 struct jffs2_raw_xattr *rx, uint32_t ofs,
317 struct jffs2_summary *s)
318 {
319 struct jffs2_xattr_datum *xd;
320 uint32_t xid, version, totlen, crc;
321 int err;
323 crc = crc32(0, rx, sizeof(struct jffs2_raw_xattr) - 4);
324 if (crc != je32_to_cpu(rx->node_crc)) {
325 JFFS2_WARNING("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
326 ofs, je32_to_cpu(rx->node_crc), crc);
327 if ((err = jffs2_scan_dirty_space(c, jeb, je32_to_cpu(rx->totlen))))
328 return err;
329 return 0;
330 }
332 xid = je32_to_cpu(rx->xid);
333 version = je32_to_cpu(rx->version);
335 totlen = PAD(sizeof(struct jffs2_raw_xattr)
336 + rx->name_len + 1 + je16_to_cpu(rx->value_len));
337 if (totlen != je32_to_cpu(rx->totlen)) {
338 JFFS2_WARNING("node length mismatch at %#08x, read=%u, calc=%u\n",
339 ofs, je32_to_cpu(rx->totlen), totlen);
340 if ((err = jffs2_scan_dirty_space(c, jeb, je32_to_cpu(rx->totlen))))
341 return err;
342 return 0;
343 }
345 xd = jffs2_setup_xattr_datum(c, xid, version);
346 if (IS_ERR(xd))
347 return PTR_ERR(xd);
349 if (xd->version > version) {
350 struct jffs2_raw_node_ref *raw
351 = jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, totlen, NULL);
352 raw->next_in_ino = xd->node->next_in_ino;
353 xd->node->next_in_ino = raw;
354 } else {
355 xd->version = version;
356 xd->xprefix = rx->xprefix;
357 xd->name_len = rx->name_len;
358 xd->value_len = je16_to_cpu(rx->value_len);
359 xd->data_crc = je32_to_cpu(rx->data_crc);
361 jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, totlen, (void *)xd);
362 }
364 if (jffs2_sum_active())
365 jffs2_sum_add_xattr_mem(s, rx, ofs - jeb->offset);
366 dbg_xattr("scaning xdatum at %#08x (xid=%u, version=%u)\n",
367 ofs, xd->xid, xd->version);
368 return 0;
369 }
371 static int jffs2_scan_xref_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
372 struct jffs2_raw_xref *rr, uint32_t ofs,
373 struct jffs2_summary *s)
374 {
375 struct jffs2_xattr_ref *ref;
376 uint32_t crc;
377 int err;
379 crc = crc32(0, rr, sizeof(*rr) - 4);
380 if (crc != je32_to_cpu(rr->node_crc)) {
381 JFFS2_WARNING("node CRC failed at %#08x, read=%#08x, calc=%#08x\n",
382 ofs, je32_to_cpu(rr->node_crc), crc);
383 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(rr->totlen)))))
384 return err;
385 return 0;
386 }
388 if (PAD(sizeof(struct jffs2_raw_xref)) != je32_to_cpu(rr->totlen)) {
389 JFFS2_WARNING("node length mismatch at %#08x, read=%u, calc=%zd\n",
390 ofs, je32_to_cpu(rr->totlen),
391 PAD(sizeof(struct jffs2_raw_xref)));
392 if ((err = jffs2_scan_dirty_space(c, jeb, je32_to_cpu(rr->totlen))))
393 return err;
394 return 0;
395 }
397 ref = jffs2_alloc_xattr_ref();
398 if (!ref)
399 return -ENOMEM;
401 /* BEFORE jffs2_build_xattr_subsystem() called,
402 * and AFTER xattr_ref is marked as a dead xref,
403 * ref->xid is used to store 32bit xid, xd is not used
404 * ref->ino is used to store 32bit inode-number, ic is not used
405 * Thoes variables are declared as union, thus using those
406 * are exclusive. In a similar way, ref->next is temporarily
407 * used to chain all xattr_ref object. It's re-chained to
408 * jffs2_inode_cache in jffs2_build_xattr_subsystem() correctly.
409 */
410 ref->ino = je32_to_cpu(rr->ino);
411 ref->xid = je32_to_cpu(rr->xid);
412 ref->xseqno = je32_to_cpu(rr->xseqno);
413 if (ref->xseqno > c->highest_xseqno)
414 c->highest_xseqno = (ref->xseqno & ~XREF_DELETE_MARKER);
415 ref->next = c->xref_temp;
416 c->xref_temp = ref;
418 jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, PAD(je32_to_cpu(rr->totlen)), (void *)ref);
420 if (jffs2_sum_active())
421 jffs2_sum_add_xref_mem(s, rr, ofs - jeb->offset);
422 dbg_xattr("scan xref at %#08x (xid=%u, ino=%u)\n",
423 ofs, ref->xid, ref->ino);
424 return 0;
425 }
426 #endif
428 /* Called with 'buf_size == 0' if buf is in fact a pointer _directly_ into
429 the flash, XIP-style */
430 static int jffs2_scan_eraseblock (struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
431 unsigned char *buf, uint32_t buf_size, struct jffs2_summary *s) {
432 struct jffs2_unknown_node *node;
433 struct jffs2_unknown_node crcnode;
434 uint32_t ofs, prevofs;
435 uint32_t hdr_crc, buf_ofs, buf_len;
436 int err;
437 int noise = 0;
440 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
441 int cleanmarkerfound = 0;
442 #endif
444 ofs = jeb->offset;
445 prevofs = jeb->offset - 1;
447 D1(printk(KERN_DEBUG "jffs2_scan_eraseblock(): Scanning block at 0x%x\n", ofs));
449 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
450 if (jffs2_cleanmarker_oob(c)) {
451 int ret = jffs2_check_nand_cleanmarker(c, jeb);
452 D2(printk(KERN_NOTICE "jffs_check_nand_cleanmarker returned %d\n",ret));
453 /* Even if it's not found, we still scan to see
454 if the block is empty. We use this information
455 to decide whether to erase it or not. */
456 switch (ret) {
457 case 0: cleanmarkerfound = 1; break;
458 case 1: break;
459 case 2: return BLK_STATE_BADBLOCK;
460 case 3: return BLK_STATE_ALLDIRTY; /* Block has failed to erase min. once */
461 default: return ret;
462 }
463 }
464 #endif
466 if (jffs2_sum_active()) {
467 struct jffs2_sum_marker *sm;
468 void *sumptr = NULL;
469 uint32_t sumlen;
471 if (!buf_size) {
472 /* XIP case. Just look, point at the summary if it's there */
473 sm = (void *)buf + c->sector_size - sizeof(*sm);
474 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) {
475 sumptr = buf + je32_to_cpu(sm->offset);
476 sumlen = c->sector_size - je32_to_cpu(sm->offset);
477 }
478 } else {
479 /* If NAND flash, read a whole page of it. Else just the end */
480 if (c->wbuf_pagesize)
481 buf_len = c->wbuf_pagesize;
482 else
483 buf_len = sizeof(*sm);
485 /* Read as much as we want into the _end_ of the preallocated buffer */
486 err = jffs2_fill_scan_buf(c, buf + buf_size - buf_len,
487 jeb->offset + c->sector_size - buf_len,
488 buf_len);
489 if (err)
490 return err;
492 sm = (void *)buf + buf_size - sizeof(*sm);
493 if (je32_to_cpu(sm->magic) == JFFS2_SUM_MAGIC) {
494 sumlen = c->sector_size - je32_to_cpu(sm->offset);
495 sumptr = buf + buf_size - sumlen;
497 /* Now, make sure the summary itself is available */
498 if (sumlen > buf_size) {
499 /* Need to kmalloc for this. */
500 sumptr = kmalloc(sumlen, GFP_KERNEL);
501 if (!sumptr)
502 return -ENOMEM;
503 memcpy(sumptr + sumlen - buf_len, buf + buf_size - buf_len, buf_len);
504 }
505 if (buf_len < sumlen) {
506 /* Need to read more so that the entire summary node is present */
507 err = jffs2_fill_scan_buf(c, sumptr,
508 jeb->offset + c->sector_size - sumlen,
509 sumlen - buf_len);
510 if (err)
511 return err;
512 }
513 }
515 }
517 if (sumptr) {
518 err = jffs2_sum_scan_sumnode(c, jeb, sumptr, sumlen, &pseudo_random);
520 if (buf_size && sumlen > buf_size)
521 kfree(sumptr);
522 /* If it returns with a real error, bail.
523 If it returns positive, that's a block classification
524 (i.e. BLK_STATE_xxx) so return that too.
525 If it returns zero, fall through to full scan. */
526 if (err)
527 return err;
528 }
529 }
531 buf_ofs = jeb->offset;
533 if (!buf_size) {
534 /* This is the XIP case -- we're reading _directly_ from the flash chip */
535 buf_len = c->sector_size;
536 } else {
537 buf_len = EMPTY_SCAN_SIZE(c->sector_size);
538 err = jffs2_fill_scan_buf(c, buf, buf_ofs, buf_len);
539 if (err)
540 return err;
541 }
543 /* We temporarily use 'ofs' as a pointer into the buffer/jeb */
544 ofs = 0;
546 /* Scan only 4KiB of 0xFF before declaring it's empty */
547 while(ofs < EMPTY_SCAN_SIZE(c->sector_size) && *(uint32_t *)(&buf[ofs]) == 0xFFFFFFFF)
548 ofs += 4;
550 if (ofs == EMPTY_SCAN_SIZE(c->sector_size)) {
551 #ifdef CONFIG_JFFS2_FS_WRITEBUFFER
552 if (jffs2_cleanmarker_oob(c)) {
553 /* scan oob, take care of cleanmarker */
554 int ret = jffs2_check_oob_empty(c, jeb, cleanmarkerfound);
555 D2(printk(KERN_NOTICE "jffs2_check_oob_empty returned %d\n",ret));
556 switch (ret) {
557 case 0: return cleanmarkerfound ? BLK_STATE_CLEANMARKER : BLK_STATE_ALLFF;
558 case 1: return BLK_STATE_ALLDIRTY;
559 default: return ret;
560 }
561 }
562 #endif
563 D1(printk(KERN_DEBUG "Block at 0x%08x is empty (erased)\n", jeb->offset));
564 if (c->cleanmarker_size == 0)
565 return BLK_STATE_CLEANMARKER; /* don't bother with re-erase */
566 else
567 return BLK_STATE_ALLFF; /* OK to erase if all blocks are like this */
568 }
569 if (ofs) {
570 D1(printk(KERN_DEBUG "Free space at %08x ends at %08x\n", jeb->offset,
571 jeb->offset + ofs));
572 if ((err = jffs2_prealloc_raw_node_refs(c, jeb, 1)))
573 return err;
574 if ((err = jffs2_scan_dirty_space(c, jeb, ofs)))
575 return err;
576 }
578 /* Now ofs is a complete physical flash offset as it always was... */
579 ofs += jeb->offset;
581 noise = 10;
583 dbg_summary("no summary found in jeb 0x%08x. Apply original scan.\n",jeb->offset);
585 scan_more:
586 while(ofs < jeb->offset + c->sector_size) {
588 jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
590 /* Make sure there are node refs available for use */
591 err = jffs2_prealloc_raw_node_refs(c, jeb, 2);
592 if (err)
593 return err;
595 cond_resched();
597 if (ofs & 3) {
598 printk(KERN_WARNING "Eep. ofs 0x%08x not word-aligned!\n", ofs);
599 ofs = PAD(ofs);
600 continue;
601 }
602 if (ofs == prevofs) {
603 printk(KERN_WARNING "ofs 0x%08x has already been seen. Skipping\n", ofs);
604 if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
605 return err;
606 ofs += 4;
607 continue;
608 }
609 prevofs = ofs;
611 if (jeb->offset + c->sector_size < ofs + sizeof(*node)) {
612 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),
613 jeb->offset, c->sector_size, ofs, sizeof(*node)));
614 if ((err = jffs2_scan_dirty_space(c, jeb, (jeb->offset + c->sector_size)-ofs)))
615 return err;
616 break;
617 }
619 if (buf_ofs + buf_len < ofs + sizeof(*node)) {
620 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
621 D1(printk(KERN_DEBUG "Fewer than %zd bytes (node header) left to end of buf. Reading 0x%x at 0x%08x\n",
622 sizeof(struct jffs2_unknown_node), buf_len, ofs));
623 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
624 if (err)
625 return err;
626 buf_ofs = ofs;
627 }
629 node = (struct jffs2_unknown_node *)&buf[ofs-buf_ofs];
631 if (*(uint32_t *)(&buf[ofs-buf_ofs]) == 0xffffffff) {
632 uint32_t inbuf_ofs;
633 uint32_t empty_start;
635 empty_start = ofs;
636 ofs += 4;
638 D1(printk(KERN_DEBUG "Found empty flash at 0x%08x\n", ofs));
639 more_empty:
640 inbuf_ofs = ofs - buf_ofs;
641 while (inbuf_ofs < buf_len) {
642 if (*(uint32_t *)(&buf[inbuf_ofs]) != 0xffffffff) {
643 printk(KERN_WARNING "Empty flash at 0x%08x ends at 0x%08x\n",
644 empty_start, ofs);
645 if ((err = jffs2_scan_dirty_space(c, jeb, ofs-empty_start)))
646 return err;
647 goto scan_more;
648 }
650 inbuf_ofs+=4;
651 ofs += 4;
652 }
653 /* Ran off end. */
654 D1(printk(KERN_DEBUG "Empty flash to end of buffer at 0x%08x\n", ofs));
656 /* If we're only checking the beginning of a block with a cleanmarker,
657 bail now */
658 if (buf_ofs == jeb->offset && jeb->used_size == PAD(c->cleanmarker_size) &&
659 c->cleanmarker_size && !jeb->dirty_size && !ref_next(jeb->first_node)) {
660 D1(printk(KERN_DEBUG "%d bytes at start of block seems clean... assuming all clean\n", EMPTY_SCAN_SIZE(c->sector_size)));
661 return BLK_STATE_CLEANMARKER;
662 }
664 /* See how much more there is to read in this eraseblock... */
665 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
666 if (!buf_len) {
667 /* No more to read. Break out of main loop without marking
668 this range of empty space as dirty (because it's not) */
669 D1(printk(KERN_DEBUG "Empty flash at %08x runs to end of block. Treating as free_space\n",
670 empty_start));
671 break;
672 }
673 D1(printk(KERN_DEBUG "Reading another 0x%x at 0x%08x\n", buf_len, ofs));
674 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
675 if (err)
676 return err;
677 buf_ofs = ofs;
678 goto more_empty;
679 }
681 if (ofs == jeb->offset && je16_to_cpu(node->magic) == KSAMTIB_CIGAM_2SFFJ) {
682 printk(KERN_WARNING "Magic bitmask is backwards at offset 0x%08x. Wrong endian filesystem?\n", ofs);
683 if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
684 return err;
685 ofs += 4;
686 continue;
687 }
688 if (je16_to_cpu(node->magic) == JFFS2_DIRTY_BITMASK) {
689 D1(printk(KERN_DEBUG "Dirty bitmask at 0x%08x\n", ofs));
690 if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
691 return err;
692 ofs += 4;
693 continue;
694 }
695 if (je16_to_cpu(node->magic) == JFFS2_OLD_MAGIC_BITMASK) {
696 printk(KERN_WARNING "Old JFFS2 bitmask found at 0x%08x\n", ofs);
697 printk(KERN_WARNING "You cannot use older JFFS2 filesystems with newer kernels\n");
698 if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
699 return err;
700 ofs += 4;
701 continue;
702 }
703 if (je16_to_cpu(node->magic) != JFFS2_MAGIC_BITMASK) {
704 /* OK. We're out of possibilities. Whinge and move on */
705 noisy_printk(&noise, "jffs2_scan_eraseblock(): Magic bitmask 0x%04x not found at 0x%08x: 0x%04x instead\n",
706 JFFS2_MAGIC_BITMASK, ofs,
707 je16_to_cpu(node->magic));
708 if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
709 return err;
710 ofs += 4;
711 continue;
712 }
713 /* We seem to have a node of sorts. Check the CRC */
714 crcnode.magic = node->magic;
715 crcnode.nodetype = cpu_to_je16( je16_to_cpu(node->nodetype) | JFFS2_NODE_ACCURATE);
716 crcnode.totlen = node->totlen;
717 hdr_crc = crc32(0, &crcnode, sizeof(crcnode)-4);
719 if (hdr_crc != je32_to_cpu(node->hdr_crc)) {
720 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",
721 ofs, je16_to_cpu(node->magic),
722 je16_to_cpu(node->nodetype),
723 je32_to_cpu(node->totlen),
724 je32_to_cpu(node->hdr_crc),
725 hdr_crc);
726 if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
727 return err;
728 ofs += 4;
729 continue;
730 }
732 if (ofs + je32_to_cpu(node->totlen) >
733 jeb->offset + c->sector_size) {
734 /* Eep. Node goes over the end of the erase block. */
735 printk(KERN_WARNING "Node at 0x%08x with length 0x%08x would run over the end of the erase block\n",
736 ofs, je32_to_cpu(node->totlen));
737 printk(KERN_WARNING "Perhaps the file system was created with the wrong erase size?\n");
738 if ((err = jffs2_scan_dirty_space(c, jeb, 4)))
739 return err;
740 ofs += 4;
741 continue;
742 }
744 if (!(je16_to_cpu(node->nodetype) & JFFS2_NODE_ACCURATE)) {
745 /* Wheee. This is an obsoleted node */
746 D2(printk(KERN_DEBUG "Node at 0x%08x is obsolete. Skipping\n", ofs));
747 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
748 return err;
749 ofs += PAD(je32_to_cpu(node->totlen));
750 continue;
751 }
753 switch(je16_to_cpu(node->nodetype)) {
754 case JFFS2_NODETYPE_INODE:
755 if (buf_ofs + buf_len < ofs + sizeof(struct jffs2_raw_inode)) {
756 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
757 D1(printk(KERN_DEBUG "Fewer than %zd bytes (inode node) left to end of buf. Reading 0x%x at 0x%08x\n",
758 sizeof(struct jffs2_raw_inode), buf_len, ofs));
759 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
760 if (err)
761 return err;
762 buf_ofs = ofs;
763 node = (void *)buf;
764 }
765 err = jffs2_scan_inode_node(c, jeb, (void *)node, ofs, s);
766 if (err) return err;
767 ofs += PAD(je32_to_cpu(node->totlen));
768 break;
770 case JFFS2_NODETYPE_DIRENT:
771 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
772 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
773 D1(printk(KERN_DEBUG "Fewer than %d bytes (dirent node) left to end of buf. Reading 0x%x at 0x%08x\n",
774 je32_to_cpu(node->totlen), buf_len, ofs));
775 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
776 if (err)
777 return err;
778 buf_ofs = ofs;
779 node = (void *)buf;
780 }
781 err = jffs2_scan_dirent_node(c, jeb, (void *)node, ofs, s);
782 if (err) return err;
783 ofs += PAD(je32_to_cpu(node->totlen));
784 break;
786 #ifdef CONFIG_JFFS2_FS_XATTR
787 case JFFS2_NODETYPE_XATTR:
788 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
789 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
790 D1(printk(KERN_DEBUG "Fewer than %d bytes (xattr node)"
791 " left to end of buf. Reading 0x%x at 0x%08x\n",
792 je32_to_cpu(node->totlen), buf_len, ofs));
793 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
794 if (err)
795 return err;
796 buf_ofs = ofs;
797 node = (void *)buf;
798 }
799 err = jffs2_scan_xattr_node(c, jeb, (void *)node, ofs, s);
800 if (err)
801 return err;
802 ofs += PAD(je32_to_cpu(node->totlen));
803 break;
804 case JFFS2_NODETYPE_XREF:
805 if (buf_ofs + buf_len < ofs + je32_to_cpu(node->totlen)) {
806 buf_len = min_t(uint32_t, buf_size, jeb->offset + c->sector_size - ofs);
807 D1(printk(KERN_DEBUG "Fewer than %d bytes (xref node)"
808 " left to end of buf. Reading 0x%x at 0x%08x\n",
809 je32_to_cpu(node->totlen), buf_len, ofs));
810 err = jffs2_fill_scan_buf(c, buf, ofs, buf_len);
811 if (err)
812 return err;
813 buf_ofs = ofs;
814 node = (void *)buf;
815 }
816 err = jffs2_scan_xref_node(c, jeb, (void *)node, ofs, s);
817 if (err)
818 return err;
819 ofs += PAD(je32_to_cpu(node->totlen));
820 break;
821 #endif /* CONFIG_JFFS2_FS_XATTR */
823 case JFFS2_NODETYPE_CLEANMARKER:
824 D1(printk(KERN_DEBUG "CLEANMARKER node found at 0x%08x\n", ofs));
825 if (je32_to_cpu(node->totlen) != c->cleanmarker_size) {
826 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x has totlen 0x%x != normal 0x%x\n",
827 ofs, je32_to_cpu(node->totlen), c->cleanmarker_size);
828 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(sizeof(struct jffs2_unknown_node)))))
829 return err;
830 ofs += PAD(sizeof(struct jffs2_unknown_node));
831 } else if (jeb->first_node) {
832 printk(KERN_NOTICE "CLEANMARKER node found at 0x%08x, not first node in block (0x%08x)\n", ofs, jeb->offset);
833 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(sizeof(struct jffs2_unknown_node)))))
834 return err;
835 ofs += PAD(sizeof(struct jffs2_unknown_node));
836 } else {
837 jffs2_link_node_ref(c, jeb, ofs | REF_NORMAL, c->cleanmarker_size, NULL);
839 ofs += PAD(c->cleanmarker_size);
840 }
841 break;
843 case JFFS2_NODETYPE_PADDING:
844 if (jffs2_sum_active())
845 jffs2_sum_add_padding_mem(s, je32_to_cpu(node->totlen));
846 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
847 return err;
848 ofs += PAD(je32_to_cpu(node->totlen));
849 break;
851 default:
852 switch (je16_to_cpu(node->nodetype) & JFFS2_COMPAT_MASK) {
853 case JFFS2_FEATURE_ROCOMPAT:
854 printk(KERN_NOTICE "Read-only compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
855 c->flags |= JFFS2_SB_FLAG_RO;
856 if (!(jffs2_is_readonly(c)))
857 return -EROFS;
858 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
859 return err;
860 ofs += PAD(je32_to_cpu(node->totlen));
861 break;
863 case JFFS2_FEATURE_INCOMPAT:
864 printk(KERN_NOTICE "Incompatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs);
865 return -EINVAL;
867 case JFFS2_FEATURE_RWCOMPAT_DELETE:
868 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
869 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(node->totlen)))))
870 return err;
871 ofs += PAD(je32_to_cpu(node->totlen));
872 break;
874 case JFFS2_FEATURE_RWCOMPAT_COPY: {
875 D1(printk(KERN_NOTICE "Unknown but compatible feature node (0x%04x) found at offset 0x%08x\n", je16_to_cpu(node->nodetype), ofs));
877 jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, PAD(je32_to_cpu(node->totlen)), NULL);
879 /* We can't summarise nodes we don't grok */
880 jffs2_sum_disable_collecting(s);
881 ofs += PAD(je32_to_cpu(node->totlen));
882 break;
883 }
884 }
885 }
886 }
888 if (jffs2_sum_active()) {
889 if (PAD(s->sum_size + JFFS2_SUMMARY_FRAME_SIZE) > jeb->free_size) {
890 dbg_summary("There is not enough space for "
891 "summary information, disabling for this jeb!\n");
892 jffs2_sum_disable_collecting(s);
893 }
894 }
896 D1(printk(KERN_DEBUG "Block at 0x%08x: free 0x%08x, dirty 0x%08x, unchecked 0x%08x, used 0x%08x, wasted 0x%08x\n",
897 jeb->offset,jeb->free_size, jeb->dirty_size, jeb->unchecked_size, jeb->used_size, jeb->wasted_size));
899 /* mark_node_obsolete can add to wasted !! */
900 if (jeb->wasted_size) {
901 jeb->dirty_size += jeb->wasted_size;
902 c->dirty_size += jeb->wasted_size;
903 c->wasted_size -= jeb->wasted_size;
904 jeb->wasted_size = 0;
905 }
907 return jffs2_scan_classify_jeb(c, jeb);
908 }
910 struct jffs2_inode_cache *jffs2_scan_make_ino_cache(struct jffs2_sb_info *c, uint32_t ino)
911 {
912 struct jffs2_inode_cache *ic;
914 ic = jffs2_get_ino_cache(c, ino);
915 if (ic)
916 return ic;
918 if (ino > c->highest_ino)
919 c->highest_ino = ino;
921 ic = jffs2_alloc_inode_cache();
922 if (!ic) {
923 printk(KERN_NOTICE "jffs2_scan_make_inode_cache(): allocation of inode cache failed\n");
924 return NULL;
925 }
926 memset(ic, 0, sizeof(*ic));
928 ic->ino = ino;
929 ic->nodes = (void *)ic;
930 jffs2_add_ino_cache(c, ic);
931 if (ino == 1)
932 ic->nlink = 1;
933 return ic;
934 }
936 static int jffs2_scan_inode_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
937 struct jffs2_raw_inode *ri, uint32_t ofs, struct jffs2_summary *s)
938 {
939 struct jffs2_inode_cache *ic;
940 uint32_t ino = je32_to_cpu(ri->ino);
941 int err;
943 D1(printk(KERN_DEBUG "jffs2_scan_inode_node(): Node at 0x%08x\n", ofs));
945 /* We do very little here now. Just check the ino# to which we should attribute
946 this node; we can do all the CRC checking etc. later. There's a tradeoff here --
947 we used to scan the flash once only, reading everything we want from it into
948 memory, then building all our in-core data structures and freeing the extra
949 information. Now we allow the first part of the mount to complete a lot quicker,
950 but we have to go _back_ to the flash in order to finish the CRC checking, etc.
951 Which means that the _full_ amount of time to get to proper write mode with GC
952 operational may actually be _longer_ than before. Sucks to be me. */
954 ic = jffs2_get_ino_cache(c, ino);
955 if (!ic) {
956 /* Inocache get failed. Either we read a bogus ino# or it's just genuinely the
957 first node we found for this inode. Do a CRC check to protect against the former
958 case */
959 uint32_t crc = crc32(0, ri, sizeof(*ri)-8);
961 if (crc != je32_to_cpu(ri->node_crc)) {
962 printk(KERN_NOTICE "jffs2_scan_inode_node(): CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
963 ofs, je32_to_cpu(ri->node_crc), crc);
964 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */
965 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(ri->totlen)))))
966 return err;
967 return 0;
968 }
969 ic = jffs2_scan_make_ino_cache(c, ino);
970 if (!ic)
971 return -ENOMEM;
972 }
974 /* Wheee. It worked */
975 jffs2_link_node_ref(c, jeb, ofs | REF_UNCHECKED, PAD(je32_to_cpu(ri->totlen)), ic);
977 D1(printk(KERN_DEBUG "Node is ino #%u, version %d. Range 0x%x-0x%x\n",
978 je32_to_cpu(ri->ino), je32_to_cpu(ri->version),
979 je32_to_cpu(ri->offset),
980 je32_to_cpu(ri->offset)+je32_to_cpu(ri->dsize)));
982 pseudo_random += je32_to_cpu(ri->version);
984 if (jffs2_sum_active()) {
985 jffs2_sum_add_inode_mem(s, ri, ofs - jeb->offset);
986 }
988 return 0;
989 }
991 static int jffs2_scan_dirent_node(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
992 struct jffs2_raw_dirent *rd, uint32_t ofs, struct jffs2_summary *s)
993 {
994 struct jffs2_full_dirent *fd;
995 struct jffs2_inode_cache *ic;
996 uint32_t crc;
997 int err;
999 D1(printk(KERN_DEBUG "jffs2_scan_dirent_node(): Node at 0x%08x\n", ofs));
1001 /* We don't get here unless the node is still valid, so we don't have to
1002 mask in the ACCURATE bit any more. */
1003 crc = crc32(0, rd, sizeof(*rd)-8);
1005 if (crc != je32_to_cpu(rd->node_crc)) {
1006 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Node CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
1007 ofs, je32_to_cpu(rd->node_crc), crc);
1008 /* We believe totlen because the CRC on the node _header_ was OK, just the node itself failed. */
1009 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(rd->totlen)))))
1010 return err;
1011 return 0;
1014 pseudo_random += je32_to_cpu(rd->version);
1016 fd = jffs2_alloc_full_dirent(rd->nsize+1);
1017 if (!fd) {
1018 return -ENOMEM;
1020 memcpy(&fd->name, rd->name, rd->nsize);
1021 fd->name[rd->nsize] = 0;
1023 crc = crc32(0, fd->name, rd->nsize);
1024 if (crc != je32_to_cpu(rd->name_crc)) {
1025 printk(KERN_NOTICE "jffs2_scan_dirent_node(): Name CRC failed on node at 0x%08x: Read 0x%08x, calculated 0x%08x\n",
1026 ofs, je32_to_cpu(rd->name_crc), crc);
1027 D1(printk(KERN_NOTICE "Name for which CRC failed is (now) '%s', ino #%d\n", fd->name, je32_to_cpu(rd->ino)));
1028 jffs2_free_full_dirent(fd);
1029 /* FIXME: Why do we believe totlen? */
1030 /* We believe totlen because the CRC on the node _header_ was OK, just the name failed. */
1031 if ((err = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(rd->totlen)))))
1032 return err;
1033 return 0;
1035 ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(rd->pino));
1036 if (!ic) {
1037 jffs2_free_full_dirent(fd);
1038 return -ENOMEM;
1041 fd->raw = jffs2_link_node_ref(c, jeb, ofs | REF_PRISTINE, PAD(je32_to_cpu(rd->totlen)), ic);
1043 fd->next = NULL;
1044 fd->version = je32_to_cpu(rd->version);
1045 fd->ino = je32_to_cpu(rd->ino);
1046 fd->nhash = full_name_hash(fd->name, rd->nsize);
1047 fd->type = rd->type;
1048 jffs2_add_fd_to_list(c, fd, &ic->scan_dents);
1050 if (jffs2_sum_active()) {
1051 jffs2_sum_add_dirent_mem(s, rd, ofs - jeb->offset);
1054 return 0;
1057 static int count_list(struct list_head *l)
1059 uint32_t count = 0;
1060 struct list_head *tmp;
1062 list_for_each(tmp, l) {
1063 count++;
1065 return count;
1068 /* Note: This breaks if list_empty(head). I don't care. You
1069 might, if you copy this code and use it elsewhere :) */
1070 static void rotate_list(struct list_head *head, uint32_t count)
1072 struct list_head *n = head->next;
1074 list_del(head);
1075 while(count--) {
1076 n = n->next;
1078 list_add(head, n);
1081 void jffs2_rotate_lists(struct jffs2_sb_info *c)
1083 uint32_t x;
1084 uint32_t rotateby;
1086 x = count_list(&c->clean_list);
1087 if (x) {
1088 rotateby = pseudo_random % x;
1089 rotate_list((&c->clean_list), rotateby);
1092 x = count_list(&c->very_dirty_list);
1093 if (x) {
1094 rotateby = pseudo_random % x;
1095 rotate_list((&c->very_dirty_list), rotateby);
1098 x = count_list(&c->dirty_list);
1099 if (x) {
1100 rotateby = pseudo_random % x;
1101 rotate_list((&c->dirty_list), rotateby);
1104 x = count_list(&c->erasable_list);
1105 if (x) {
1106 rotateby = pseudo_random % x;
1107 rotate_list((&c->erasable_list), rotateby);
1110 if (c->nr_erasing_blocks) {
1111 rotateby = pseudo_random % c->nr_erasing_blocks;
1112 rotate_list((&c->erase_pending_list), rotateby);
1115 if (c->nr_free_blocks) {
1116 rotateby = pseudo_random % c->nr_free_blocks;
1117 rotate_list((&c->free_list), rotateby);