1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright © 2001-2007 Red Hat, Inc.
5  * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
6  *
7  * Created by David Woodhouse <dwmw2@infradead.org>
8  *
9  * For licensing information, see the file 'LICENCE' in this directory.
10  *
11  */
12 
13 #include <linux/kernel.h>
14 #include <linux/slab.h>
15 #include <linux/mtd/mtd.h>
16 #include <linux/compiler.h>
17 #include <linux/crc32.h>
18 #include <linux/sched.h>
19 #include <linux/pagemap.h>
20 #include "nodelist.h"
21 
22 struct erase_priv_struct {
23 	struct jffs2_eraseblock *jeb;
24 	struct jffs2_sb_info *c;
25 };
26 
27 #ifndef __ECOS
28 static void jffs2_erase_callback(struct erase_info *);
29 #endif
30 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset);
31 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
32 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
33 
jffs2_erase_block(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)34 static void jffs2_erase_block(struct jffs2_sb_info *c,
35 			      struct jffs2_eraseblock *jeb)
36 {
37 	int ret;
38 	uint32_t bad_offset;
39 #ifdef __ECOS
40        ret = jffs2_flash_erase(c, jeb);
41        if (!ret) {
42 	       jffs2_erase_succeeded(c, jeb);
43 	       return;
44        }
45        bad_offset = jeb->offset;
46 #else /* Linux */
47 	struct erase_info *instr;
48 
49 	D1(printk(KERN_DEBUG "jffs2_erase_block(): erase block %#08x (range %#08x-%#08x)\n",
50 				jeb->offset, jeb->offset, jeb->offset + c->sector_size));
51 	instr = kmalloc(sizeof(struct erase_info) + sizeof(struct erase_priv_struct), GFP_KERNEL);
52 	if (!instr) {
53 		printk(KERN_WARNING "kmalloc for struct erase_info in jffs2_erase_block failed. Refiling block for later\n");
54 		mutex_lock(&c->erase_free_sem);
55 		spin_lock(&c->erase_completion_lock);
56 		list_move(&jeb->list, &c->erase_pending_list);
57 		c->erasing_size -= c->sector_size;
58 		c->dirty_size += c->sector_size;
59 		jeb->dirty_size = c->sector_size;
60 		spin_unlock(&c->erase_completion_lock);
61 		mutex_unlock(&c->erase_free_sem);
62 		return;
63 	}
64 
65 	memset(instr, 0, sizeof(*instr));
66 
67 	instr->mtd = c->mtd;
68 	instr->addr = jeb->offset;
69 	instr->len = c->sector_size;
70 	instr->callback = jffs2_erase_callback;
71 	instr->priv = (unsigned long)(&instr[1]);
72 	instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
73 
74 	((struct erase_priv_struct *)instr->priv)->jeb = jeb;
75 	((struct erase_priv_struct *)instr->priv)->c = c;
76 
77 	ret = c->mtd->erase(c->mtd, instr);
78 	if (!ret)
79 		return;
80 
81 	bad_offset = instr->fail_addr;
82 	kfree(instr);
83 #endif /* __ECOS */
84 
85 	if (ret == -ENOMEM || ret == -EAGAIN) {
86 		/* Erase failed immediately. Refile it on the list */
87 		D1(printk(KERN_DEBUG "Erase at 0x%08x failed: %d. Refiling on erase_pending_list\n", jeb->offset, ret));
88 		mutex_lock(&c->erase_free_sem);
89 		spin_lock(&c->erase_completion_lock);
90 		list_move(&jeb->list, &c->erase_pending_list);
91 		c->erasing_size -= c->sector_size;
92 		c->dirty_size += c->sector_size;
93 		jeb->dirty_size = c->sector_size;
94 		spin_unlock(&c->erase_completion_lock);
95 		mutex_unlock(&c->erase_free_sem);
96 		return;
97 	}
98 
99 	if (ret == -EROFS)
100 		printk(KERN_WARNING "Erase at 0x%08x failed immediately: -EROFS. Is the sector locked?\n", jeb->offset);
101 	else
102 		printk(KERN_WARNING "Erase at 0x%08x failed immediately: errno %d\n", jeb->offset, ret);
103 
104 	jffs2_erase_failed(c, jeb, bad_offset);
105 }
106 
jffs2_erase_pending_blocks(struct jffs2_sb_info * c,int count)107 int jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count)
108 {
109 	struct jffs2_eraseblock *jeb;
110 	int work_done = 0;
111 
112 	mutex_lock(&c->erase_free_sem);
113 
114 	spin_lock(&c->erase_completion_lock);
115 
116 	while (!list_empty(&c->erase_complete_list) ||
117 	       !list_empty(&c->erase_pending_list)) {
118 
119 		if (!list_empty(&c->erase_complete_list)) {
120 			jeb = list_entry(c->erase_complete_list.next, struct jffs2_eraseblock, list);
121 			list_move(&jeb->list, &c->erase_checking_list);
122 			spin_unlock(&c->erase_completion_lock);
123 			mutex_unlock(&c->erase_free_sem);
124 			jffs2_mark_erased_block(c, jeb);
125 
126 			work_done++;
127 			if (!--count) {
128 				D1(printk(KERN_DEBUG "Count reached. jffs2_erase_pending_blocks leaving\n"));
129 				goto done;
130 			}
131 
132 		} else if (!list_empty(&c->erase_pending_list)) {
133 			jeb = list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list);
134 			D1(printk(KERN_DEBUG "Starting erase of pending block 0x%08x\n", jeb->offset));
135 			list_del(&jeb->list);
136 			c->erasing_size += c->sector_size;
137 			c->wasted_size -= jeb->wasted_size;
138 			c->free_size -= jeb->free_size;
139 			c->used_size -= jeb->used_size;
140 			c->dirty_size -= jeb->dirty_size;
141 			jeb->wasted_size = jeb->used_size = jeb->dirty_size = jeb->free_size = 0;
142 			jffs2_free_jeb_node_refs(c, jeb);
143 			list_add(&jeb->list, &c->erasing_list);
144 			spin_unlock(&c->erase_completion_lock);
145 			mutex_unlock(&c->erase_free_sem);
146 
147 			jffs2_erase_block(c, jeb);
148 
149 		} else {
150 			BUG();
151 		}
152 
153 		/* Be nice */
154 		cond_resched();
155 		mutex_lock(&c->erase_free_sem);
156 		spin_lock(&c->erase_completion_lock);
157 	}
158 
159 	spin_unlock(&c->erase_completion_lock);
160 	mutex_unlock(&c->erase_free_sem);
161  done:
162 	D1(printk(KERN_DEBUG "jffs2_erase_pending_blocks completed\n"));
163 	return work_done;
164 }
165 
jffs2_erase_succeeded(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)166 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
167 {
168 	D1(printk(KERN_DEBUG "Erase completed successfully at 0x%08x\n", jeb->offset));
169 	mutex_lock(&c->erase_free_sem);
170 	spin_lock(&c->erase_completion_lock);
171 	list_move_tail(&jeb->list, &c->erase_complete_list);
172 	/* Wake the GC thread to mark them clean */
173 	jffs2_garbage_collect_trigger(c);
174 	spin_unlock(&c->erase_completion_lock);
175 	mutex_unlock(&c->erase_free_sem);
176 	wake_up(&c->erase_wait);
177 }
178 
jffs2_erase_failed(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb,uint32_t bad_offset)179 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset)
180 {
181 	/* For NAND, if the failure did not occur at the device level for a
182 	   specific physical page, don't bother updating the bad block table. */
183 	if (jffs2_cleanmarker_oob(c) && (bad_offset != (uint32_t)MTD_FAIL_ADDR_UNKNOWN)) {
184 		/* We had a device-level failure to erase.  Let's see if we've
185 		   failed too many times. */
186 		if (!jffs2_write_nand_badblock(c, jeb, bad_offset)) {
187 			/* We'd like to give this block another try. */
188 			mutex_lock(&c->erase_free_sem);
189 			spin_lock(&c->erase_completion_lock);
190 			list_move(&jeb->list, &c->erase_pending_list);
191 			c->erasing_size -= c->sector_size;
192 			c->dirty_size += c->sector_size;
193 			jeb->dirty_size = c->sector_size;
194 			spin_unlock(&c->erase_completion_lock);
195 			mutex_unlock(&c->erase_free_sem);
196 			return;
197 		}
198 	}
199 
200 	mutex_lock(&c->erase_free_sem);
201 	spin_lock(&c->erase_completion_lock);
202 	c->erasing_size -= c->sector_size;
203 	c->bad_size += c->sector_size;
204 	list_move(&jeb->list, &c->bad_list);
205 	c->nr_erasing_blocks--;
206 	spin_unlock(&c->erase_completion_lock);
207 	mutex_unlock(&c->erase_free_sem);
208 	wake_up(&c->erase_wait);
209 }
210 
211 #ifndef __ECOS
jffs2_erase_callback(struct erase_info * instr)212 static void jffs2_erase_callback(struct erase_info *instr)
213 {
214 	struct erase_priv_struct *priv = (void *)instr->priv;
215 
216 	if(instr->state != MTD_ERASE_DONE) {
217 		printk(KERN_WARNING "Erase at 0x%08llx finished, but state != MTD_ERASE_DONE. State is 0x%x instead.\n",
218 			(unsigned long long)instr->addr, instr->state);
219 		jffs2_erase_failed(priv->c, priv->jeb, instr->fail_addr);
220 	} else {
221 		jffs2_erase_succeeded(priv->c, priv->jeb);
222 	}
223 	kfree(instr);
224 }
225 #endif /* !__ECOS */
226 
227 /* Hmmm. Maybe we should accept the extra space it takes and make
228    this a standard doubly-linked list? */
jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info * c,struct jffs2_raw_node_ref * ref,struct jffs2_eraseblock * jeb)229 static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c,
230 			struct jffs2_raw_node_ref *ref, struct jffs2_eraseblock *jeb)
231 {
232 	struct jffs2_inode_cache *ic = NULL;
233 	struct jffs2_raw_node_ref **prev;
234 
235 	prev = &ref->next_in_ino;
236 
237 	/* Walk the inode's list once, removing any nodes from this eraseblock */
238 	while (1) {
239 		if (!(*prev)->next_in_ino) {
240 			/* We're looking at the jffs2_inode_cache, which is
241 			   at the end of the linked list. Stash it and continue
242 			   from the beginning of the list */
243 			ic = (struct jffs2_inode_cache *)(*prev);
244 			prev = &ic->nodes;
245 			continue;
246 		}
247 
248 		if (SECTOR_ADDR((*prev)->flash_offset) == jeb->offset) {
249 			/* It's in the block we're erasing */
250 			struct jffs2_raw_node_ref *this;
251 
252 			this = *prev;
253 			*prev = this->next_in_ino;
254 			this->next_in_ino = NULL;
255 
256 			if (this == ref)
257 				break;
258 
259 			continue;
260 		}
261 		/* Not to be deleted. Skip */
262 		prev = &((*prev)->next_in_ino);
263 	}
264 
265 	/* PARANOIA */
266 	if (!ic) {
267 		JFFS2_WARNING("inode_cache/xattr_datum/xattr_ref"
268 			      " not found in remove_node_refs()!!\n");
269 		return;
270 	}
271 
272 	D1(printk(KERN_DEBUG "Removed nodes in range 0x%08x-0x%08x from ino #%u\n",
273 		  jeb->offset, jeb->offset + c->sector_size, ic->ino));
274 
275 	D2({
276 		int i=0;
277 		struct jffs2_raw_node_ref *this;
278 		printk(KERN_DEBUG "After remove_node_refs_from_ino_list: \n");
279 
280 		this = ic->nodes;
281 
282 		printk(KERN_DEBUG);
283 		while(this) {
284 			printk(KERN_CONT "0x%08x(%d)->",
285 			       ref_offset(this), ref_flags(this));
286 			if (++i == 5) {
287 				printk(KERN_DEBUG);
288 				i=0;
289 			}
290 			this = this->next_in_ino;
291 		}
292 		printk(KERN_CONT "\n");
293 	});
294 
295 	switch (ic->class) {
296 #ifdef CONFIG_JFFS2_FS_XATTR
297 		case RAWNODE_CLASS_XATTR_DATUM:
298 			jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic);
299 			break;
300 		case RAWNODE_CLASS_XATTR_REF:
301 			jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic);
302 			break;
303 #endif
304 		default:
305 			if (ic->nodes == (void *)ic && ic->pino_nlink == 0)
306 				jffs2_del_ino_cache(c, ic);
307 	}
308 }
309 
jffs2_free_jeb_node_refs(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)310 void jffs2_free_jeb_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
311 {
312 	struct jffs2_raw_node_ref *block, *ref;
313 	D1(printk(KERN_DEBUG "Freeing all node refs for eraseblock offset 0x%08x\n", jeb->offset));
314 
315 	block = ref = jeb->first_node;
316 
317 	while (ref) {
318 		if (ref->flash_offset == REF_LINK_NODE) {
319 			ref = ref->next_in_ino;
320 			jffs2_free_refblock(block);
321 			block = ref;
322 			continue;
323 		}
324 		if (ref->flash_offset != REF_EMPTY_NODE && ref->next_in_ino)
325 			jffs2_remove_node_refs_from_ino_list(c, ref, jeb);
326 		/* else it was a non-inode node or already removed, so don't bother */
327 
328 		ref++;
329 	}
330 	jeb->first_node = jeb->last_node = NULL;
331 }
332 
jffs2_block_check_erase(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb,uint32_t * bad_offset)333 static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t *bad_offset)
334 {
335 	void *ebuf;
336 	uint32_t ofs;
337 	size_t retlen;
338 	int ret = -EIO;
339 
340 	if (c->mtd->point) {
341 		unsigned long *wordebuf;
342 
343 		ret = c->mtd->point(c->mtd, jeb->offset, c->sector_size,
344 				    &retlen, &ebuf, NULL);
345 		if (ret) {
346 			D1(printk(KERN_DEBUG "MTD point failed %d\n", ret));
347 			goto do_flash_read;
348 		}
349 		if (retlen < c->sector_size) {
350 			/* Don't muck about if it won't let us point to the whole erase sector */
351 			D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", retlen));
352 			c->mtd->unpoint(c->mtd, jeb->offset, retlen);
353 			goto do_flash_read;
354 		}
355 		wordebuf = ebuf-sizeof(*wordebuf);
356 		retlen /= sizeof(*wordebuf);
357 		do {
358 		   if (*++wordebuf != ~0)
359 			   break;
360 		} while(--retlen);
361 		c->mtd->unpoint(c->mtd, jeb->offset, c->sector_size);
362 		if (retlen) {
363 			printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08tx\n",
364 			       *wordebuf, jeb->offset + c->sector_size-retlen*sizeof(*wordebuf));
365 			return -EIO;
366 		}
367 		return 0;
368 	}
369  do_flash_read:
370 	ebuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
371 	if (!ebuf) {
372 		printk(KERN_WARNING "Failed to allocate page buffer for verifying erase at 0x%08x. Refiling\n", jeb->offset);
373 		return -EAGAIN;
374 	}
375 
376 	D1(printk(KERN_DEBUG "Verifying erase at 0x%08x\n", jeb->offset));
377 
378 	for (ofs = jeb->offset; ofs < jeb->offset + c->sector_size; ) {
379 		uint32_t readlen = min((uint32_t)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
380 		int i;
381 
382 		*bad_offset = ofs;
383 
384 		ret = c->mtd->read(c->mtd, ofs, readlen, &retlen, ebuf);
385 		if (ret) {
386 			printk(KERN_WARNING "Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n", ofs, ret);
387 			ret = -EIO;
388 			goto fail;
389 		}
390 		if (retlen != readlen) {
391 			printk(KERN_WARNING "Short read from newly-erased block at 0x%08x. Wanted %d, got %zd\n", ofs, readlen, retlen);
392 			ret = -EIO;
393 			goto fail;
394 		}
395 		for (i=0; i<readlen; i += sizeof(unsigned long)) {
396 			/* It's OK. We know it's properly aligned */
397 			unsigned long *datum = ebuf + i;
398 			if (*datum + 1) {
399 				*bad_offset += i;
400 				printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08x\n", *datum, *bad_offset);
401 				ret = -EIO;
402 				goto fail;
403 			}
404 		}
405 		ofs += readlen;
406 		cond_resched();
407 	}
408 	ret = 0;
409 fail:
410 	kfree(ebuf);
411 	return ret;
412 }
413 
jffs2_mark_erased_block(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)414 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
415 {
416 	size_t retlen;
417 	int ret;
418 	uint32_t uninitialized_var(bad_offset);
419 
420 	switch (jffs2_block_check_erase(c, jeb, &bad_offset)) {
421 	case -EAGAIN:	goto refile;
422 	case -EIO:	goto filebad;
423 	}
424 
425 	/* Write the erase complete marker */
426 	D1(printk(KERN_DEBUG "Writing erased marker to block at 0x%08x\n", jeb->offset));
427 	bad_offset = jeb->offset;
428 
429 	/* Cleanmarker in oob area or no cleanmarker at all ? */
430 	if (jffs2_cleanmarker_oob(c) || c->cleanmarker_size == 0) {
431 
432 		if (jffs2_cleanmarker_oob(c)) {
433 			if (jffs2_write_nand_cleanmarker(c, jeb))
434 				goto filebad;
435 		}
436 	} else {
437 
438 		struct kvec vecs[1];
439 		struct jffs2_unknown_node marker = {
440 			.magic =	cpu_to_je16(JFFS2_MAGIC_BITMASK),
441 			.nodetype =	cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER),
442 			.totlen =	cpu_to_je32(c->cleanmarker_size)
443 		};
444 
445 		jffs2_prealloc_raw_node_refs(c, jeb, 1);
446 
447 		marker.hdr_crc = cpu_to_je32(crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4));
448 
449 		vecs[0].iov_base = (unsigned char *) &marker;
450 		vecs[0].iov_len = sizeof(marker);
451 		ret = jffs2_flash_direct_writev(c, vecs, 1, jeb->offset, &retlen);
452 
453 		if (ret || retlen != sizeof(marker)) {
454 			if (ret)
455 				printk(KERN_WARNING "Write clean marker to block at 0x%08x failed: %d\n",
456 				       jeb->offset, ret);
457 			else
458 				printk(KERN_WARNING "Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
459 				       jeb->offset, sizeof(marker), retlen);
460 
461 			goto filebad;
462 		}
463 	}
464 	/* Everything else got zeroed before the erase */
465 	jeb->free_size = c->sector_size;
466 
467 	mutex_lock(&c->erase_free_sem);
468 	spin_lock(&c->erase_completion_lock);
469 
470 	c->erasing_size -= c->sector_size;
471 	c->free_size += c->sector_size;
472 
473 	/* Account for cleanmarker now, if it's in-band */
474 	if (c->cleanmarker_size && !jffs2_cleanmarker_oob(c))
475 		jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
476 
477 	list_move_tail(&jeb->list, &c->free_list);
478 	c->nr_erasing_blocks--;
479 	c->nr_free_blocks++;
480 
481 	jffs2_dbg_acct_sanity_check_nolock(c, jeb);
482 	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
483 
484 	spin_unlock(&c->erase_completion_lock);
485 	mutex_unlock(&c->erase_free_sem);
486 	wake_up(&c->erase_wait);
487 	return;
488 
489 filebad:
490 	jffs2_erase_failed(c, jeb, bad_offset);
491 	return;
492 
493 refile:
494 	/* Stick it back on the list from whence it came and come back later */
495 	mutex_lock(&c->erase_free_sem);
496 	spin_lock(&c->erase_completion_lock);
497 	jffs2_garbage_collect_trigger(c);
498 	list_move(&jeb->list, &c->erase_complete_list);
499 	spin_unlock(&c->erase_completion_lock);
500 	mutex_unlock(&c->erase_free_sem);
501 	return;
502 }
503