xref: /linux/fs/jffs2/summary.c (revision 40d269c000bda9fcd276a0412a9cebd3f6e344c5)
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright © 2004  Ferenc Havasi <havasi@inf.u-szeged.hu>,
5  *		     Zoltan Sogor <weth@inf.u-szeged.hu>,
6  *		     Patrik Kluba <pajko@halom.u-szeged.hu>,
7  *		     University of Szeged, Hungary
8  *	       2006  KaiGai Kohei <kaigai@ak.jp.nec.com>
9  *
10  * For licensing information, see the file 'LICENCE' in this directory.
11  *
12  */
13 
14 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
15 
16 #include <linux/kernel.h>
17 #include <linux/slab.h>
18 #include <linux/mtd/mtd.h>
19 #include <linux/pagemap.h>
20 #include <linux/crc32.h>
21 #include <linux/compiler.h>
22 #include <linux/vmalloc.h>
23 #include "nodelist.h"
24 #include "debug.h"
25 
26 int jffs2_sum_init(struct jffs2_sb_info *c)
27 {
28 	uint32_t sum_size = min_t(uint32_t, c->sector_size, MAX_SUMMARY_SIZE);
29 
30 	c->summary = kzalloc(sizeof(struct jffs2_summary), GFP_KERNEL);
31 
32 	if (!c->summary) {
33 		JFFS2_WARNING("Can't allocate memory for summary information!\n");
34 		return -ENOMEM;
35 	}
36 
37 	c->summary->sum_buf = kmalloc(sum_size, GFP_KERNEL);
38 
39 	if (!c->summary->sum_buf) {
40 		JFFS2_WARNING("Can't allocate buffer for writing out summary information!\n");
41 		kfree(c->summary);
42 		return -ENOMEM;
43 	}
44 
45 	dbg_summary("returned successfully\n");
46 
47 	return 0;
48 }
49 
50 void jffs2_sum_exit(struct jffs2_sb_info *c)
51 {
52 	dbg_summary("called\n");
53 
54 	jffs2_sum_disable_collecting(c->summary);
55 
56 	kfree(c->summary->sum_buf);
57 	c->summary->sum_buf = NULL;
58 
59 	kfree(c->summary);
60 	c->summary = NULL;
61 }
62 
63 static int jffs2_sum_add_mem(struct jffs2_summary *s, union jffs2_sum_mem *item)
64 {
65 	if (!s->sum_list_head)
66 		s->sum_list_head = (union jffs2_sum_mem *) item;
67 	if (s->sum_list_tail)
68 		s->sum_list_tail->u.next = (union jffs2_sum_mem *) item;
69 	s->sum_list_tail = (union jffs2_sum_mem *) item;
70 
71 	switch (je16_to_cpu(item->u.nodetype)) {
72 		case JFFS2_NODETYPE_INODE:
73 			s->sum_size += JFFS2_SUMMARY_INODE_SIZE;
74 			s->sum_num++;
75 			dbg_summary("inode (%u) added to summary\n",
76 						je32_to_cpu(item->i.inode));
77 			break;
78 		case JFFS2_NODETYPE_DIRENT:
79 			s->sum_size += JFFS2_SUMMARY_DIRENT_SIZE(item->d.nsize);
80 			s->sum_num++;
81 			dbg_summary("dirent (%u) added to summary\n",
82 						je32_to_cpu(item->d.ino));
83 			break;
84 #ifdef CONFIG_JFFS2_FS_XATTR
85 		case JFFS2_NODETYPE_XATTR:
86 			s->sum_size += JFFS2_SUMMARY_XATTR_SIZE;
87 			s->sum_num++;
88 			dbg_summary("xattr (xid=%u, version=%u) added to summary\n",
89 				    je32_to_cpu(item->x.xid), je32_to_cpu(item->x.version));
90 			break;
91 		case JFFS2_NODETYPE_XREF:
92 			s->sum_size += JFFS2_SUMMARY_XREF_SIZE;
93 			s->sum_num++;
94 			dbg_summary("xref added to summary\n");
95 			break;
96 #endif
97 		default:
98 			JFFS2_WARNING("UNKNOWN node type %u\n",
99 					    je16_to_cpu(item->u.nodetype));
100 			return 1;
101 	}
102 	return 0;
103 }
104 
105 
106 /* The following 3 functions are called from scan.c to collect summary info for not closed jeb */
107 
108 int jffs2_sum_add_padding_mem(struct jffs2_summary *s, uint32_t size)
109 {
110 	dbg_summary("called with %u\n", size);
111 	s->sum_padded += size;
112 	return 0;
113 }
114 
115 int jffs2_sum_add_inode_mem(struct jffs2_summary *s, struct jffs2_raw_inode *ri,
116 				uint32_t ofs)
117 {
118 	struct jffs2_sum_inode_mem *temp = kmalloc(sizeof(struct jffs2_sum_inode_mem), GFP_KERNEL);
119 
120 	if (!temp)
121 		return -ENOMEM;
122 
123 	temp->nodetype = ri->nodetype;
124 	temp->inode = ri->ino;
125 	temp->version = ri->version;
126 	temp->offset = cpu_to_je32(ofs); /* relative offset from the beginning of the jeb */
127 	temp->totlen = ri->totlen;
128 	temp->next = NULL;
129 
130 	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
131 }
132 
133 int jffs2_sum_add_dirent_mem(struct jffs2_summary *s, struct jffs2_raw_dirent *rd,
134 				uint32_t ofs)
135 {
136 	struct jffs2_sum_dirent_mem *temp =
137 		kmalloc(sizeof(struct jffs2_sum_dirent_mem) + rd->nsize, GFP_KERNEL);
138 
139 	if (!temp)
140 		return -ENOMEM;
141 
142 	temp->nodetype = rd->nodetype;
143 	temp->totlen = rd->totlen;
144 	temp->offset = cpu_to_je32(ofs);	/* relative from the beginning of the jeb */
145 	temp->pino = rd->pino;
146 	temp->version = rd->version;
147 	temp->ino = rd->ino;
148 	temp->nsize = rd->nsize;
149 	temp->type = rd->type;
150 	temp->next = NULL;
151 
152 	memcpy(temp->name, rd->name, rd->nsize);
153 
154 	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
155 }
156 
157 #ifdef CONFIG_JFFS2_FS_XATTR
158 int jffs2_sum_add_xattr_mem(struct jffs2_summary *s, struct jffs2_raw_xattr *rx, uint32_t ofs)
159 {
160 	struct jffs2_sum_xattr_mem *temp;
161 
162 	temp = kmalloc(sizeof(struct jffs2_sum_xattr_mem), GFP_KERNEL);
163 	if (!temp)
164 		return -ENOMEM;
165 
166 	temp->nodetype = rx->nodetype;
167 	temp->xid = rx->xid;
168 	temp->version = rx->version;
169 	temp->offset = cpu_to_je32(ofs);
170 	temp->totlen = rx->totlen;
171 	temp->next = NULL;
172 
173 	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
174 }
175 
176 int jffs2_sum_add_xref_mem(struct jffs2_summary *s, struct jffs2_raw_xref *rr, uint32_t ofs)
177 {
178 	struct jffs2_sum_xref_mem *temp;
179 
180 	temp = kmalloc(sizeof(struct jffs2_sum_xref_mem), GFP_KERNEL);
181 	if (!temp)
182 		return -ENOMEM;
183 
184 	temp->nodetype = rr->nodetype;
185 	temp->offset = cpu_to_je32(ofs);
186 	temp->next = NULL;
187 
188 	return jffs2_sum_add_mem(s, (union jffs2_sum_mem *)temp);
189 }
190 #endif
191 /* Cleanup every collected summary information */
192 
193 static void jffs2_sum_clean_collected(struct jffs2_summary *s)
194 {
195 	union jffs2_sum_mem *temp;
196 
197 	if (!s->sum_list_head) {
198 		dbg_summary("already empty\n");
199 	}
200 	while (s->sum_list_head) {
201 		temp = s->sum_list_head;
202 		s->sum_list_head = s->sum_list_head->u.next;
203 		kfree(temp);
204 	}
205 	s->sum_list_tail = NULL;
206 	s->sum_padded = 0;
207 	s->sum_num = 0;
208 }
209 
210 void jffs2_sum_reset_collected(struct jffs2_summary *s)
211 {
212 	dbg_summary("called\n");
213 	jffs2_sum_clean_collected(s);
214 	s->sum_size = 0;
215 }
216 
217 void jffs2_sum_disable_collecting(struct jffs2_summary *s)
218 {
219 	dbg_summary("called\n");
220 	jffs2_sum_clean_collected(s);
221 	s->sum_size = JFFS2_SUMMARY_NOSUM_SIZE;
222 }
223 
224 int jffs2_sum_is_disabled(struct jffs2_summary *s)
225 {
226 	return (s->sum_size == JFFS2_SUMMARY_NOSUM_SIZE);
227 }
228 
229 /* Move the collected summary information into sb (called from scan.c) */
230 
231 void jffs2_sum_move_collected(struct jffs2_sb_info *c, struct jffs2_summary *s)
232 {
233 	dbg_summary("oldsize=0x%x oldnum=%u => newsize=0x%x newnum=%u\n",
234 				c->summary->sum_size, c->summary->sum_num,
235 				s->sum_size, s->sum_num);
236 
237 	c->summary->sum_size = s->sum_size;
238 	c->summary->sum_num = s->sum_num;
239 	c->summary->sum_padded = s->sum_padded;
240 	c->summary->sum_list_head = s->sum_list_head;
241 	c->summary->sum_list_tail = s->sum_list_tail;
242 
243 	s->sum_list_head = s->sum_list_tail = NULL;
244 }
245 
246 /* Called from wbuf.c to collect writed node info */
247 
248 int jffs2_sum_add_kvec(struct jffs2_sb_info *c, const struct kvec *invecs,
249 				unsigned long count, uint32_t ofs)
250 {
251 	union jffs2_node_union *node;
252 	struct jffs2_eraseblock *jeb;
253 
254 	if (c->summary->sum_size == JFFS2_SUMMARY_NOSUM_SIZE) {
255 		dbg_summary("Summary is disabled for this jeb! Skipping summary info!\n");
256 		return 0;
257 	}
258 
259 	node = invecs[0].iov_base;
260 	jeb = &c->blocks[ofs / c->sector_size];
261 	ofs -= jeb->offset;
262 
263 	switch (je16_to_cpu(node->u.nodetype)) {
264 		case JFFS2_NODETYPE_INODE: {
265 			struct jffs2_sum_inode_mem *temp =
266 				kmalloc(sizeof(struct jffs2_sum_inode_mem), GFP_KERNEL);
267 
268 			if (!temp)
269 				goto no_mem;
270 
271 			temp->nodetype = node->i.nodetype;
272 			temp->inode = node->i.ino;
273 			temp->version = node->i.version;
274 			temp->offset = cpu_to_je32(ofs);
275 			temp->totlen = node->i.totlen;
276 			temp->next = NULL;
277 
278 			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
279 		}
280 
281 		case JFFS2_NODETYPE_DIRENT: {
282 			struct jffs2_sum_dirent_mem *temp =
283 				kmalloc(sizeof(struct jffs2_sum_dirent_mem) + node->d.nsize, GFP_KERNEL);
284 
285 			if (!temp)
286 				goto no_mem;
287 
288 			temp->nodetype = node->d.nodetype;
289 			temp->totlen = node->d.totlen;
290 			temp->offset = cpu_to_je32(ofs);
291 			temp->pino = node->d.pino;
292 			temp->version = node->d.version;
293 			temp->ino = node->d.ino;
294 			temp->nsize = node->d.nsize;
295 			temp->type = node->d.type;
296 			temp->next = NULL;
297 
298 			switch (count) {
299 				case 1:
300 					memcpy(temp->name,node->d.name,node->d.nsize);
301 					break;
302 
303 				case 2:
304 					memcpy(temp->name,invecs[1].iov_base,node->d.nsize);
305 					break;
306 
307 				default:
308 					BUG();	/* impossible count value */
309 					break;
310 			}
311 
312 			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
313 		}
314 #ifdef CONFIG_JFFS2_FS_XATTR
315 		case JFFS2_NODETYPE_XATTR: {
316 			struct jffs2_sum_xattr_mem *temp;
317 			temp = kmalloc(sizeof(struct jffs2_sum_xattr_mem), GFP_KERNEL);
318 			if (!temp)
319 				goto no_mem;
320 
321 			temp->nodetype = node->x.nodetype;
322 			temp->xid = node->x.xid;
323 			temp->version = node->x.version;
324 			temp->totlen = node->x.totlen;
325 			temp->offset = cpu_to_je32(ofs);
326 			temp->next = NULL;
327 
328 			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
329 		}
330 		case JFFS2_NODETYPE_XREF: {
331 			struct jffs2_sum_xref_mem *temp;
332 			temp = kmalloc(sizeof(struct jffs2_sum_xref_mem), GFP_KERNEL);
333 			if (!temp)
334 				goto no_mem;
335 			temp->nodetype = node->r.nodetype;
336 			temp->offset = cpu_to_je32(ofs);
337 			temp->next = NULL;
338 
339 			return jffs2_sum_add_mem(c->summary, (union jffs2_sum_mem *)temp);
340 		}
341 #endif
342 		case JFFS2_NODETYPE_PADDING:
343 			dbg_summary("node PADDING\n");
344 			c->summary->sum_padded += je32_to_cpu(node->u.totlen);
345 			break;
346 
347 		case JFFS2_NODETYPE_CLEANMARKER:
348 			dbg_summary("node CLEANMARKER\n");
349 			break;
350 
351 		case JFFS2_NODETYPE_SUMMARY:
352 			dbg_summary("node SUMMARY\n");
353 			break;
354 
355 		default:
356 			/* If you implement a new node type you should also implement
357 			   summary support for it or disable summary.
358 			*/
359 			BUG();
360 			break;
361 	}
362 
363 	return 0;
364 
365 no_mem:
366 	JFFS2_WARNING("MEMORY ALLOCATION ERROR!");
367 	return -ENOMEM;
368 }
369 
370 static struct jffs2_raw_node_ref *sum_link_node_ref(struct jffs2_sb_info *c,
371 						    struct jffs2_eraseblock *jeb,
372 						    uint32_t ofs, uint32_t len,
373 						    struct jffs2_inode_cache *ic)
374 {
375 	/* If there was a gap, mark it dirty */
376 	if ((ofs & ~3) > c->sector_size - jeb->free_size) {
377 		/* Ew. Summary doesn't actually tell us explicitly about dirty space */
378 		jffs2_scan_dirty_space(c, jeb, (ofs & ~3) - (c->sector_size - jeb->free_size));
379 	}
380 
381 	return jffs2_link_node_ref(c, jeb, jeb->offset + ofs, len, ic);
382 }
383 
384 /* Process the stored summary information - helper function for jffs2_sum_scan_sumnode() */
385 
386 static int jffs2_sum_process_sum_data(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
387 				struct jffs2_raw_summary *summary, uint32_t *pseudo_random)
388 {
389 	struct jffs2_inode_cache *ic;
390 	struct jffs2_full_dirent *fd;
391 	void *sp;
392 	int i, ino;
393 	int err;
394 
395 	sp = summary->sum;
396 
397 	for (i=0; i<je32_to_cpu(summary->sum_num); i++) {
398 		dbg_summary("processing summary index %d\n", i);
399 
400 		cond_resched();
401 
402 		/* Make sure there's a spare ref for dirty space */
403 		err = jffs2_prealloc_raw_node_refs(c, jeb, 2);
404 		if (err)
405 			return err;
406 
407 		switch (je16_to_cpu(((struct jffs2_sum_unknown_flash *)sp)->nodetype)) {
408 			case JFFS2_NODETYPE_INODE: {
409 				struct jffs2_sum_inode_flash *spi;
410 				spi = sp;
411 
412 				ino = je32_to_cpu(spi->inode);
413 
414 				dbg_summary("Inode at 0x%08x-0x%08x\n",
415 					    jeb->offset + je32_to_cpu(spi->offset),
416 					    jeb->offset + je32_to_cpu(spi->offset) + je32_to_cpu(spi->totlen));
417 
418 				ic = jffs2_scan_make_ino_cache(c, ino);
419 				if (!ic) {
420 					JFFS2_NOTICE("scan_make_ino_cache failed\n");
421 					return -ENOMEM;
422 				}
423 
424 				sum_link_node_ref(c, jeb, je32_to_cpu(spi->offset) | REF_UNCHECKED,
425 						  PAD(je32_to_cpu(spi->totlen)), ic);
426 
427 				*pseudo_random += je32_to_cpu(spi->version);
428 
429 				sp += JFFS2_SUMMARY_INODE_SIZE;
430 
431 				break;
432 			}
433 
434 			case JFFS2_NODETYPE_DIRENT: {
435 				struct jffs2_sum_dirent_flash *spd;
436 				int checkedlen;
437 				spd = sp;
438 
439 				dbg_summary("Dirent at 0x%08x-0x%08x\n",
440 					    jeb->offset + je32_to_cpu(spd->offset),
441 					    jeb->offset + je32_to_cpu(spd->offset) + je32_to_cpu(spd->totlen));
442 
443 
444 				/* This should never happen, but https://dev.laptop.org/ticket/4184 */
445 				checkedlen = strnlen(spd->name, spd->nsize);
446 				if (!checkedlen) {
447 					pr_err("Dirent at %08x has zero at start of name. Aborting mount.\n",
448 					       jeb->offset +
449 					       je32_to_cpu(spd->offset));
450 					return -EIO;
451 				}
452 				if (checkedlen < spd->nsize) {
453 					pr_err("Dirent at %08x has zeroes in name. Truncating to %d chars\n",
454 					       jeb->offset +
455 					       je32_to_cpu(spd->offset),
456 					       checkedlen);
457 				}
458 
459 
460 				fd = jffs2_alloc_full_dirent(checkedlen+1);
461 				if (!fd)
462 					return -ENOMEM;
463 
464 				memcpy(&fd->name, spd->name, checkedlen);
465 				fd->name[checkedlen] = 0;
466 
467 				ic = jffs2_scan_make_ino_cache(c, je32_to_cpu(spd->pino));
468 				if (!ic) {
469 					jffs2_free_full_dirent(fd);
470 					return -ENOMEM;
471 				}
472 
473 				fd->raw = sum_link_node_ref(c, jeb,  je32_to_cpu(spd->offset) | REF_UNCHECKED,
474 							    PAD(je32_to_cpu(spd->totlen)), ic);
475 
476 				fd->next = NULL;
477 				fd->version = je32_to_cpu(spd->version);
478 				fd->ino = je32_to_cpu(spd->ino);
479 				fd->nhash = full_name_hash(NULL, fd->name, checkedlen);
480 				fd->type = spd->type;
481 
482 				jffs2_add_fd_to_list(c, fd, &ic->scan_dents);
483 
484 				*pseudo_random += je32_to_cpu(spd->version);
485 
486 				sp += JFFS2_SUMMARY_DIRENT_SIZE(spd->nsize);
487 
488 				break;
489 			}
490 #ifdef CONFIG_JFFS2_FS_XATTR
491 			case JFFS2_NODETYPE_XATTR: {
492 				struct jffs2_xattr_datum *xd;
493 				struct jffs2_sum_xattr_flash *spx;
494 
495 				spx = (struct jffs2_sum_xattr_flash *)sp;
496 				dbg_summary("xattr at %#08x-%#08x (xid=%u, version=%u)\n",
497 					    jeb->offset + je32_to_cpu(spx->offset),
498 					    jeb->offset + je32_to_cpu(spx->offset) + je32_to_cpu(spx->totlen),
499 					    je32_to_cpu(spx->xid), je32_to_cpu(spx->version));
500 
501 				xd = jffs2_setup_xattr_datum(c, je32_to_cpu(spx->xid),
502 								je32_to_cpu(spx->version));
503 				if (IS_ERR(xd))
504 					return PTR_ERR(xd);
505 				if (xd->version > je32_to_cpu(spx->version)) {
506 					/* node is not the newest one */
507 					struct jffs2_raw_node_ref *raw
508 						= sum_link_node_ref(c, jeb, je32_to_cpu(spx->offset) | REF_UNCHECKED,
509 								    PAD(je32_to_cpu(spx->totlen)), NULL);
510 					raw->next_in_ino = xd->node->next_in_ino;
511 					xd->node->next_in_ino = raw;
512 				} else {
513 					xd->version = je32_to_cpu(spx->version);
514 					sum_link_node_ref(c, jeb, je32_to_cpu(spx->offset) | REF_UNCHECKED,
515 							  PAD(je32_to_cpu(spx->totlen)), (void *)xd);
516 				}
517 				*pseudo_random += je32_to_cpu(spx->xid);
518 				sp += JFFS2_SUMMARY_XATTR_SIZE;
519 
520 				break;
521 			}
522 			case JFFS2_NODETYPE_XREF: {
523 				struct jffs2_xattr_ref *ref;
524 				struct jffs2_sum_xref_flash *spr;
525 
526 				spr = (struct jffs2_sum_xref_flash *)sp;
527 				dbg_summary("xref at %#08x-%#08x\n",
528 					    jeb->offset + je32_to_cpu(spr->offset),
529 					    jeb->offset + je32_to_cpu(spr->offset) +
530 					    (uint32_t)PAD(sizeof(struct jffs2_raw_xref)));
531 
532 				ref = jffs2_alloc_xattr_ref();
533 				if (!ref) {
534 					JFFS2_NOTICE("allocation of xattr_datum failed\n");
535 					return -ENOMEM;
536 				}
537 				ref->next = c->xref_temp;
538 				c->xref_temp = ref;
539 
540 				sum_link_node_ref(c, jeb, je32_to_cpu(spr->offset) | REF_UNCHECKED,
541 						  PAD(sizeof(struct jffs2_raw_xref)), (void *)ref);
542 
543 				*pseudo_random += ref->node->flash_offset;
544 				sp += JFFS2_SUMMARY_XREF_SIZE;
545 
546 				break;
547 			}
548 #endif
549 			default : {
550 				uint16_t nodetype = je16_to_cpu(((struct jffs2_sum_unknown_flash *)sp)->nodetype);
551 				JFFS2_WARNING("Unsupported node type %x found in summary! Exiting...\n", nodetype);
552 				if ((nodetype & JFFS2_COMPAT_MASK) == JFFS2_FEATURE_INCOMPAT)
553 					return -EIO;
554 
555 				/* For compatible node types, just fall back to the full scan */
556 				c->wasted_size -= jeb->wasted_size;
557 				c->free_size += c->sector_size - jeb->free_size;
558 				c->used_size -= jeb->used_size;
559 				c->dirty_size -= jeb->dirty_size;
560 				jeb->wasted_size = jeb->used_size = jeb->dirty_size = 0;
561 				jeb->free_size = c->sector_size;
562 
563 				jffs2_free_jeb_node_refs(c, jeb);
564 				return -ENOTRECOVERABLE;
565 			}
566 		}
567 	}
568 	return 0;
569 }
570 
571 /* Process the summary node - called from jffs2_scan_eraseblock() */
572 int jffs2_sum_scan_sumnode(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
573 			   struct jffs2_raw_summary *summary, uint32_t sumsize,
574 			   uint32_t *pseudo_random)
575 {
576 	struct jffs2_unknown_node crcnode;
577 	int ret, ofs;
578 	uint32_t crc;
579 
580 	ofs = c->sector_size - sumsize;
581 
582 	dbg_summary("summary found for 0x%08x at 0x%08x (0x%x bytes)\n",
583 		    jeb->offset, jeb->offset + ofs, sumsize);
584 
585 	/* OK, now check for node validity and CRC */
586 	crcnode.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
587 	crcnode.nodetype = cpu_to_je16(JFFS2_NODETYPE_SUMMARY);
588 	crcnode.totlen = summary->totlen;
589 	crc = crc32(0, &crcnode, sizeof(crcnode)-4);
590 
591 	if (je32_to_cpu(summary->hdr_crc) != crc) {
592 		dbg_summary("Summary node header is corrupt (bad CRC or "
593 				"no summary at all)\n");
594 		goto crc_err;
595 	}
596 
597 	if (je32_to_cpu(summary->totlen) != sumsize) {
598 		dbg_summary("Summary node is corrupt (wrong erasesize?)\n");
599 		goto crc_err;
600 	}
601 
602 	crc = crc32(0, summary, sizeof(struct jffs2_raw_summary)-8);
603 
604 	if (je32_to_cpu(summary->node_crc) != crc) {
605 		dbg_summary("Summary node is corrupt (bad CRC)\n");
606 		goto crc_err;
607 	}
608 
609 	crc = crc32(0, summary->sum, sumsize - sizeof(struct jffs2_raw_summary));
610 
611 	if (je32_to_cpu(summary->sum_crc) != crc) {
612 		dbg_summary("Summary node data is corrupt (bad CRC)\n");
613 		goto crc_err;
614 	}
615 
616 	if ( je32_to_cpu(summary->cln_mkr) ) {
617 
618 		dbg_summary("Summary : CLEANMARKER node \n");
619 
620 		ret = jffs2_prealloc_raw_node_refs(c, jeb, 1);
621 		if (ret)
622 			return ret;
623 
624 		if (je32_to_cpu(summary->cln_mkr) != c->cleanmarker_size) {
625 			dbg_summary("CLEANMARKER node has totlen 0x%x != normal 0x%x\n",
626 				je32_to_cpu(summary->cln_mkr), c->cleanmarker_size);
627 			if ((ret = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(summary->cln_mkr)))))
628 				return ret;
629 		} else if (jeb->first_node) {
630 			dbg_summary("CLEANMARKER node not first node in block "
631 					"(0x%08x)\n", jeb->offset);
632 			if ((ret = jffs2_scan_dirty_space(c, jeb, PAD(je32_to_cpu(summary->cln_mkr)))))
633 				return ret;
634 		} else {
635 			jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL,
636 					    je32_to_cpu(summary->cln_mkr), NULL);
637 		}
638 	}
639 
640 	ret = jffs2_sum_process_sum_data(c, jeb, summary, pseudo_random);
641 	/* -ENOTRECOVERABLE isn't a fatal error -- it means we should do a full
642 	   scan of this eraseblock. So return zero */
643 	if (ret == -ENOTRECOVERABLE)
644 		return 0;
645 	if (ret)
646 		return ret;		/* real error */
647 
648 	/* for PARANOIA_CHECK */
649 	ret = jffs2_prealloc_raw_node_refs(c, jeb, 2);
650 	if (ret)
651 		return ret;
652 
653 	sum_link_node_ref(c, jeb, ofs | REF_NORMAL, sumsize, NULL);
654 
655 	if (unlikely(jeb->free_size)) {
656 		JFFS2_WARNING("Free size 0x%x bytes in eraseblock @0x%08x with summary?\n",
657 			      jeb->free_size, jeb->offset);
658 		jeb->wasted_size += jeb->free_size;
659 		c->wasted_size += jeb->free_size;
660 		c->free_size -= jeb->free_size;
661 		jeb->free_size = 0;
662 	}
663 
664 	return jffs2_scan_classify_jeb(c, jeb);
665 
666 crc_err:
667 	JFFS2_WARNING("Summary node crc error, skipping summary information.\n");
668 
669 	return 0;
670 }
671 
672 /* Write summary data to flash - helper function for jffs2_sum_write_sumnode() */
673 
674 static int jffs2_sum_write_data(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb,
675 				uint32_t infosize, uint32_t datasize, int padsize)
676 {
677 	struct jffs2_raw_summary isum;
678 	union jffs2_sum_mem *temp;
679 	struct jffs2_sum_marker *sm;
680 	struct kvec vecs[2];
681 	uint32_t sum_ofs;
682 	void *wpage;
683 	int ret;
684 	size_t retlen;
685 
686 	if (padsize + datasize > MAX_SUMMARY_SIZE) {
687 		/* It won't fit in the buffer. Abort summary for this jeb */
688 		jffs2_sum_disable_collecting(c->summary);
689 
690 		JFFS2_WARNING("Summary too big (%d data, %d pad) in eraseblock at %08x\n",
691 			      datasize, padsize, jeb->offset);
692 		/* Non-fatal */
693 		return 0;
694 	}
695 	/* Is there enough space for summary? */
696 	if (padsize < 0) {
697 		/* don't try to write out summary for this jeb */
698 		jffs2_sum_disable_collecting(c->summary);
699 
700 		JFFS2_WARNING("Not enough space for summary, padsize = %d\n",
701 			      padsize);
702 		/* Non-fatal */
703 		return 0;
704 	}
705 
706 	memset(c->summary->sum_buf, 0xff, datasize);
707 	memset(&isum, 0, sizeof(isum));
708 
709 	isum.magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
710 	isum.nodetype = cpu_to_je16(JFFS2_NODETYPE_SUMMARY);
711 	isum.totlen = cpu_to_je32(infosize);
712 	isum.hdr_crc = cpu_to_je32(crc32(0, &isum, sizeof(struct jffs2_unknown_node) - 4));
713 	isum.padded = cpu_to_je32(c->summary->sum_padded);
714 	isum.cln_mkr = cpu_to_je32(c->cleanmarker_size);
715 	isum.sum_num = cpu_to_je32(c->summary->sum_num);
716 	wpage = c->summary->sum_buf;
717 
718 	while (c->summary->sum_num) {
719 		temp = c->summary->sum_list_head;
720 
721 		switch (je16_to_cpu(temp->u.nodetype)) {
722 			case JFFS2_NODETYPE_INODE: {
723 				struct jffs2_sum_inode_flash *sino_ptr = wpage;
724 
725 				sino_ptr->nodetype = temp->i.nodetype;
726 				sino_ptr->inode = temp->i.inode;
727 				sino_ptr->version = temp->i.version;
728 				sino_ptr->offset = temp->i.offset;
729 				sino_ptr->totlen = temp->i.totlen;
730 
731 				wpage += JFFS2_SUMMARY_INODE_SIZE;
732 
733 				break;
734 			}
735 
736 			case JFFS2_NODETYPE_DIRENT: {
737 				struct jffs2_sum_dirent_flash *sdrnt_ptr = wpage;
738 
739 				sdrnt_ptr->nodetype = temp->d.nodetype;
740 				sdrnt_ptr->totlen = temp->d.totlen;
741 				sdrnt_ptr->offset = temp->d.offset;
742 				sdrnt_ptr->pino = temp->d.pino;
743 				sdrnt_ptr->version = temp->d.version;
744 				sdrnt_ptr->ino = temp->d.ino;
745 				sdrnt_ptr->nsize = temp->d.nsize;
746 				sdrnt_ptr->type = temp->d.type;
747 
748 				memcpy(sdrnt_ptr->name, temp->d.name,
749 							temp->d.nsize);
750 
751 				wpage += JFFS2_SUMMARY_DIRENT_SIZE(temp->d.nsize);
752 
753 				break;
754 			}
755 #ifdef CONFIG_JFFS2_FS_XATTR
756 			case JFFS2_NODETYPE_XATTR: {
757 				struct jffs2_sum_xattr_flash *sxattr_ptr = wpage;
758 
759 				temp = c->summary->sum_list_head;
760 				sxattr_ptr->nodetype = temp->x.nodetype;
761 				sxattr_ptr->xid = temp->x.xid;
762 				sxattr_ptr->version = temp->x.version;
763 				sxattr_ptr->offset = temp->x.offset;
764 				sxattr_ptr->totlen = temp->x.totlen;
765 
766 				wpage += JFFS2_SUMMARY_XATTR_SIZE;
767 				break;
768 			}
769 			case JFFS2_NODETYPE_XREF: {
770 				struct jffs2_sum_xref_flash *sxref_ptr = wpage;
771 
772 				temp = c->summary->sum_list_head;
773 				sxref_ptr->nodetype = temp->r.nodetype;
774 				sxref_ptr->offset = temp->r.offset;
775 
776 				wpage += JFFS2_SUMMARY_XREF_SIZE;
777 				break;
778 			}
779 #endif
780 			default : {
781 				if ((je16_to_cpu(temp->u.nodetype) & JFFS2_COMPAT_MASK)
782 				    == JFFS2_FEATURE_RWCOMPAT_COPY) {
783 					dbg_summary("Writing unknown RWCOMPAT_COPY node type %x\n",
784 						    je16_to_cpu(temp->u.nodetype));
785 					jffs2_sum_disable_collecting(c->summary);
786 					/* The above call removes the list, nothing more to do */
787 					goto bail_rwcompat;
788 				} else {
789 					BUG();	/* unknown node in summary information */
790 				}
791 			}
792 		}
793 
794 		c->summary->sum_list_head = temp->u.next;
795 		kfree(temp);
796 
797 		c->summary->sum_num--;
798 	}
799  bail_rwcompat:
800 
801 	jffs2_sum_reset_collected(c->summary);
802 
803 	wpage += padsize;
804 
805 	sm = wpage;
806 	sm->offset = cpu_to_je32(c->sector_size - jeb->free_size);
807 	sm->magic = cpu_to_je32(JFFS2_SUM_MAGIC);
808 
809 	isum.sum_crc = cpu_to_je32(crc32(0, c->summary->sum_buf, datasize));
810 	isum.node_crc = cpu_to_je32(crc32(0, &isum, sizeof(isum) - 8));
811 
812 	vecs[0].iov_base = &isum;
813 	vecs[0].iov_len = sizeof(isum);
814 	vecs[1].iov_base = c->summary->sum_buf;
815 	vecs[1].iov_len = datasize;
816 
817 	sum_ofs = jeb->offset + c->sector_size - jeb->free_size;
818 
819 	dbg_summary("writing out data to flash to pos : 0x%08x\n", sum_ofs);
820 
821 	ret = jffs2_flash_writev(c, vecs, 2, sum_ofs, &retlen, 0);
822 
823 	if (ret || (retlen != infosize)) {
824 
825 		JFFS2_WARNING("Write of %u bytes at 0x%08x failed. returned %d, retlen %zd\n",
826 			      infosize, sum_ofs, ret, retlen);
827 
828 		if (retlen) {
829 			/* Waste remaining space */
830 			spin_lock(&c->erase_completion_lock);
831 			jffs2_link_node_ref(c, jeb, sum_ofs | REF_OBSOLETE, infosize, NULL);
832 			spin_unlock(&c->erase_completion_lock);
833 		}
834 
835 		c->summary->sum_size = JFFS2_SUMMARY_NOSUM_SIZE;
836 
837 		return 0;
838 	}
839 
840 	spin_lock(&c->erase_completion_lock);
841 	jffs2_link_node_ref(c, jeb, sum_ofs | REF_NORMAL, infosize, NULL);
842 	spin_unlock(&c->erase_completion_lock);
843 
844 	return 0;
845 }
846 
847 /* Write out summary information - called from jffs2_do_reserve_space */
848 
849 int jffs2_sum_write_sumnode(struct jffs2_sb_info *c)
850 	__must_hold(&c->erase_completion_block)
851 {
852 	int datasize, infosize, padsize;
853 	struct jffs2_eraseblock *jeb;
854 	int ret = 0;
855 
856 	dbg_summary("called\n");
857 
858 	spin_unlock(&c->erase_completion_lock);
859 
860 	jeb = c->nextblock;
861 	jffs2_prealloc_raw_node_refs(c, jeb, 1);
862 
863 	if (!c->summary->sum_num || !c->summary->sum_list_head) {
864 		JFFS2_WARNING("Empty summary info!!!\n");
865 		BUG();
866 	}
867 
868 	datasize = c->summary->sum_size + sizeof(struct jffs2_sum_marker);
869 	infosize = sizeof(struct jffs2_raw_summary) + datasize;
870 	padsize = jeb->free_size - infosize;
871 	infosize += padsize;
872 	datasize += padsize;
873 
874 	ret = jffs2_sum_write_data(c, jeb, infosize, datasize, padsize);
875 	spin_lock(&c->erase_completion_lock);
876 	return ret;
877 }
878