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 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
14 
15 #include <linux/kernel.h>
16 #include <linux/slab.h>
17 #include <linux/mtd/mtd.h>
18 #include <linux/compiler.h>
19 #include <linux/crc32.h>
20 #include <linux/sched.h>
21 #include <linux/pagemap.h>
22 #include "nodelist.h"
23 
24 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset);
25 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
26 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
27 
jffs2_erase_block(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)28 static void jffs2_erase_block(struct jffs2_sb_info *c,
29 			      struct jffs2_eraseblock *jeb)
30 {
31 	int ret;
32 	uint32_t bad_offset;
33 #ifdef __ECOS
34        ret = jffs2_flash_erase(c, jeb);
35        if (!ret) {
36 	       jffs2_erase_succeeded(c, jeb);
37 	       return;
38        }
39        bad_offset = jeb->offset;
40 #else /* Linux */
41 	struct erase_info *instr;
42 
43 	jffs2_dbg(1, "%s(): erase block %#08x (range %#08x-%#08x)\n",
44 		  __func__,
45 		  jeb->offset, jeb->offset, jeb->offset + c->sector_size);
46 	instr = kzalloc(sizeof(struct erase_info), GFP_KERNEL);
47 	if (!instr) {
48 		pr_warn("kzalloc for struct erase_info in jffs2_erase_block failed. Refiling block for later\n");
49 		mutex_lock(&c->erase_free_sem);
50 		spin_lock(&c->erase_completion_lock);
51 		list_move(&jeb->list, &c->erase_pending_list);
52 		c->erasing_size -= c->sector_size;
53 		c->dirty_size += c->sector_size;
54 		jeb->dirty_size = c->sector_size;
55 		spin_unlock(&c->erase_completion_lock);
56 		mutex_unlock(&c->erase_free_sem);
57 		return;
58 	}
59 
60 	instr->addr = jeb->offset;
61 	instr->len = c->sector_size;
62 
63 	ret = mtd_erase(c->mtd, instr);
64 	if (!ret) {
65 		jffs2_erase_succeeded(c, jeb);
66 		kfree(instr);
67 		return;
68 	}
69 
70 	bad_offset = instr->fail_addr;
71 	kfree(instr);
72 #endif /* __ECOS */
73 
74 	if (ret == -ENOMEM || ret == -EAGAIN) {
75 		/* Erase failed immediately. Refile it on the list */
76 		jffs2_dbg(1, "Erase at 0x%08x failed: %d. Refiling on erase_pending_list\n",
77 			  jeb->offset, ret);
78 		mutex_lock(&c->erase_free_sem);
79 		spin_lock(&c->erase_completion_lock);
80 		list_move(&jeb->list, &c->erase_pending_list);
81 		c->erasing_size -= c->sector_size;
82 		c->dirty_size += c->sector_size;
83 		jeb->dirty_size = c->sector_size;
84 		spin_unlock(&c->erase_completion_lock);
85 		mutex_unlock(&c->erase_free_sem);
86 		return;
87 	}
88 
89 	if (ret == -EROFS)
90 		pr_warn("Erase at 0x%08x failed immediately: -EROFS. Is the sector locked?\n",
91 			jeb->offset);
92 	else
93 		pr_warn("Erase at 0x%08x failed immediately: errno %d\n",
94 			jeb->offset, ret);
95 
96 	jffs2_erase_failed(c, jeb, bad_offset);
97 }
98 
jffs2_erase_pending_blocks(struct jffs2_sb_info * c,int count)99 int jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count)
100 {
101 	struct jffs2_eraseblock *jeb;
102 	int work_done = 0;
103 
104 	mutex_lock(&c->erase_free_sem);
105 
106 	spin_lock(&c->erase_completion_lock);
107 
108 	while (!list_empty(&c->erase_complete_list) ||
109 	       !list_empty(&c->erase_pending_list)) {
110 
111 		if (!list_empty(&c->erase_complete_list)) {
112 			jeb = list_entry(c->erase_complete_list.next, struct jffs2_eraseblock, list);
113 			list_move(&jeb->list, &c->erase_checking_list);
114 			spin_unlock(&c->erase_completion_lock);
115 			mutex_unlock(&c->erase_free_sem);
116 			jffs2_mark_erased_block(c, jeb);
117 
118 			work_done++;
119 			if (!--count) {
120 				jffs2_dbg(1, "Count reached. jffs2_erase_pending_blocks leaving\n");
121 				goto done;
122 			}
123 
124 		} else if (!list_empty(&c->erase_pending_list)) {
125 			jeb = list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list);
126 			jffs2_dbg(1, "Starting erase of pending block 0x%08x\n",
127 				  jeb->offset);
128 			list_del(&jeb->list);
129 			c->erasing_size += c->sector_size;
130 			c->wasted_size -= jeb->wasted_size;
131 			c->free_size -= jeb->free_size;
132 			c->used_size -= jeb->used_size;
133 			c->dirty_size -= jeb->dirty_size;
134 			jeb->wasted_size = jeb->used_size = jeb->dirty_size = jeb->free_size = 0;
135 			jffs2_free_jeb_node_refs(c, jeb);
136 			list_add(&jeb->list, &c->erasing_list);
137 			spin_unlock(&c->erase_completion_lock);
138 			mutex_unlock(&c->erase_free_sem);
139 
140 			jffs2_erase_block(c, jeb);
141 
142 		} else {
143 			BUG();
144 		}
145 
146 		/* Be nice */
147 		cond_resched();
148 		mutex_lock(&c->erase_free_sem);
149 		spin_lock(&c->erase_completion_lock);
150 	}
151 
152 	spin_unlock(&c->erase_completion_lock);
153 	mutex_unlock(&c->erase_free_sem);
154  done:
155 	jffs2_dbg(1, "jffs2_erase_pending_blocks completed\n");
156 	return work_done;
157 }
158 
jffs2_erase_succeeded(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)159 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
160 {
161 	jffs2_dbg(1, "Erase completed successfully at 0x%08x\n", jeb->offset);
162 	mutex_lock(&c->erase_free_sem);
163 	spin_lock(&c->erase_completion_lock);
164 	list_move_tail(&jeb->list, &c->erase_complete_list);
165 	/* Wake the GC thread to mark them clean */
166 	jffs2_garbage_collect_trigger(c);
167 	spin_unlock(&c->erase_completion_lock);
168 	mutex_unlock(&c->erase_free_sem);
169 	wake_up(&c->erase_wait);
170 }
171 
jffs2_erase_failed(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb,uint32_t bad_offset)172 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset)
173 {
174 	/* For NAND, if the failure did not occur at the device level for a
175 	   specific physical page, don't bother updating the bad block table. */
176 	if (jffs2_cleanmarker_oob(c) && (bad_offset != (uint32_t)MTD_FAIL_ADDR_UNKNOWN)) {
177 		/* We had a device-level failure to erase.  Let's see if we've
178 		   failed too many times. */
179 		if (!jffs2_write_nand_badblock(c, jeb, bad_offset)) {
180 			/* We'd like to give this block another try. */
181 			mutex_lock(&c->erase_free_sem);
182 			spin_lock(&c->erase_completion_lock);
183 			list_move(&jeb->list, &c->erase_pending_list);
184 			c->erasing_size -= c->sector_size;
185 			c->dirty_size += c->sector_size;
186 			jeb->dirty_size = c->sector_size;
187 			spin_unlock(&c->erase_completion_lock);
188 			mutex_unlock(&c->erase_free_sem);
189 			return;
190 		}
191 	}
192 
193 	mutex_lock(&c->erase_free_sem);
194 	spin_lock(&c->erase_completion_lock);
195 	c->erasing_size -= c->sector_size;
196 	c->bad_size += c->sector_size;
197 	list_move(&jeb->list, &c->bad_list);
198 	c->nr_erasing_blocks--;
199 	spin_unlock(&c->erase_completion_lock);
200 	mutex_unlock(&c->erase_free_sem);
201 	wake_up(&c->erase_wait);
202 }
203 
204 /* Hmmm. Maybe we should accept the extra space it takes and make
205    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)206 static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c,
207 			struct jffs2_raw_node_ref *ref, struct jffs2_eraseblock *jeb)
208 {
209 	struct jffs2_inode_cache *ic = NULL;
210 	struct jffs2_raw_node_ref **prev;
211 
212 	prev = &ref->next_in_ino;
213 
214 	/* Walk the inode's list once, removing any nodes from this eraseblock */
215 	while (1) {
216 		if (!(*prev)->next_in_ino) {
217 			/* We're looking at the jffs2_inode_cache, which is
218 			   at the end of the linked list. Stash it and continue
219 			   from the beginning of the list */
220 			ic = (struct jffs2_inode_cache *)(*prev);
221 			prev = &ic->nodes;
222 			continue;
223 		}
224 
225 		if (SECTOR_ADDR((*prev)->flash_offset) == jeb->offset) {
226 			/* It's in the block we're erasing */
227 			struct jffs2_raw_node_ref *this;
228 
229 			this = *prev;
230 			*prev = this->next_in_ino;
231 			this->next_in_ino = NULL;
232 
233 			if (this == ref)
234 				break;
235 
236 			continue;
237 		}
238 		/* Not to be deleted. Skip */
239 		prev = &((*prev)->next_in_ino);
240 	}
241 
242 	/* PARANOIA */
243 	if (!ic) {
244 		JFFS2_WARNING("inode_cache/xattr_datum/xattr_ref"
245 			      " not found in remove_node_refs()!!\n");
246 		return;
247 	}
248 
249 	jffs2_dbg(1, "Removed nodes in range 0x%08x-0x%08x from ino #%u\n",
250 		  jeb->offset, jeb->offset + c->sector_size, ic->ino);
251 
252 	D2({
253 		int i=0;
254 		struct jffs2_raw_node_ref *this;
255 		printk(KERN_DEBUG "After remove_node_refs_from_ino_list: \n");
256 
257 		this = ic->nodes;
258 
259 		printk(KERN_DEBUG);
260 		while(this) {
261 			pr_cont("0x%08x(%d)->",
262 			       ref_offset(this), ref_flags(this));
263 			if (++i == 5) {
264 				printk(KERN_DEBUG);
265 				i=0;
266 			}
267 			this = this->next_in_ino;
268 		}
269 		pr_cont("\n");
270 	});
271 
272 	switch (ic->class) {
273 #ifdef CONFIG_JFFS2_FS_XATTR
274 		case RAWNODE_CLASS_XATTR_DATUM:
275 			jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic);
276 			break;
277 		case RAWNODE_CLASS_XATTR_REF:
278 			jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic);
279 			break;
280 #endif
281 		default:
282 			if (ic->nodes == (void *)ic && ic->pino_nlink == 0)
283 				jffs2_del_ino_cache(c, ic);
284 	}
285 }
286 
jffs2_free_jeb_node_refs(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)287 void jffs2_free_jeb_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
288 {
289 	struct jffs2_raw_node_ref *block, *ref;
290 	jffs2_dbg(1, "Freeing all node refs for eraseblock offset 0x%08x\n",
291 		  jeb->offset);
292 
293 	block = ref = jeb->first_node;
294 
295 	while (ref) {
296 		if (ref->flash_offset == REF_LINK_NODE) {
297 			ref = ref->next_in_ino;
298 			jffs2_free_refblock(block);
299 			block = ref;
300 			continue;
301 		}
302 		if (ref->flash_offset != REF_EMPTY_NODE && ref->next_in_ino)
303 			jffs2_remove_node_refs_from_ino_list(c, ref, jeb);
304 		/* else it was a non-inode node or already removed, so don't bother */
305 
306 		ref++;
307 	}
308 	jeb->first_node = jeb->last_node = NULL;
309 }
310 
jffs2_block_check_erase(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb,uint32_t * bad_offset)311 static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t *bad_offset)
312 {
313 	void *ebuf;
314 	uint32_t ofs;
315 	size_t retlen;
316 	int ret;
317 	unsigned long *wordebuf;
318 
319 	ret = mtd_point(c->mtd, jeb->offset, c->sector_size, &retlen,
320 			&ebuf, NULL);
321 	if (ret != -EOPNOTSUPP) {
322 		if (ret) {
323 			jffs2_dbg(1, "MTD point failed %d\n", ret);
324 			goto do_flash_read;
325 		}
326 		if (retlen < c->sector_size) {
327 			/* Don't muck about if it won't let us point to the whole erase sector */
328 			jffs2_dbg(1, "MTD point returned len too short: 0x%zx\n",
329 				  retlen);
330 			mtd_unpoint(c->mtd, jeb->offset, retlen);
331 			goto do_flash_read;
332 		}
333 		wordebuf = ebuf-sizeof(*wordebuf);
334 		retlen /= sizeof(*wordebuf);
335 		do {
336 		   if (*++wordebuf != ~0)
337 			   break;
338 		} while(--retlen);
339 		mtd_unpoint(c->mtd, jeb->offset, c->sector_size);
340 		if (retlen) {
341 			pr_warn("Newly-erased block contained word 0x%lx at offset 0x%08tx\n",
342 				*wordebuf,
343 				jeb->offset +
344 				c->sector_size-retlen * sizeof(*wordebuf));
345 			return -EIO;
346 		}
347 		return 0;
348 	}
349  do_flash_read:
350 	ebuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
351 	if (!ebuf) {
352 		pr_warn("Failed to allocate page buffer for verifying erase at 0x%08x. Refiling\n",
353 			jeb->offset);
354 		return -EAGAIN;
355 	}
356 
357 	jffs2_dbg(1, "Verifying erase at 0x%08x\n", jeb->offset);
358 
359 	for (ofs = jeb->offset; ofs < jeb->offset + c->sector_size; ) {
360 		uint32_t readlen = min((uint32_t)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
361 		int i;
362 
363 		*bad_offset = ofs;
364 
365 		ret = mtd_read(c->mtd, ofs, readlen, &retlen, ebuf);
366 		if (ret) {
367 			pr_warn("Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n",
368 				ofs, ret);
369 			ret = -EIO;
370 			goto fail;
371 		}
372 		if (retlen != readlen) {
373 			pr_warn("Short read from newly-erased block at 0x%08x. Wanted %d, got %zd\n",
374 				ofs, readlen, retlen);
375 			ret = -EIO;
376 			goto fail;
377 		}
378 		for (i=0; i<readlen; i += sizeof(unsigned long)) {
379 			/* It's OK. We know it's properly aligned */
380 			unsigned long *datum = ebuf + i;
381 			if (*datum + 1) {
382 				*bad_offset += i;
383 				pr_warn("Newly-erased block contained word 0x%lx at offset 0x%08x\n",
384 					*datum, *bad_offset);
385 				ret = -EIO;
386 				goto fail;
387 			}
388 		}
389 		ofs += readlen;
390 		cond_resched();
391 	}
392 	ret = 0;
393 fail:
394 	kfree(ebuf);
395 	return ret;
396 }
397 
jffs2_mark_erased_block(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)398 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
399 {
400 	size_t retlen;
401 	int ret;
402 	uint32_t bad_offset;
403 
404 	switch (jffs2_block_check_erase(c, jeb, &bad_offset)) {
405 	case -EAGAIN:	goto refile;
406 	case -EIO:	goto filebad;
407 	}
408 
409 	/* Write the erase complete marker */
410 	jffs2_dbg(1, "Writing erased marker to block at 0x%08x\n", jeb->offset);
411 	bad_offset = jeb->offset;
412 
413 	/* Cleanmarker in oob area or no cleanmarker at all ? */
414 	if (jffs2_cleanmarker_oob(c) || c->cleanmarker_size == 0) {
415 
416 		if (jffs2_cleanmarker_oob(c)) {
417 			if (jffs2_write_nand_cleanmarker(c, jeb))
418 				goto filebad;
419 		}
420 	} else {
421 
422 		struct kvec vecs[1];
423 		struct jffs2_unknown_node marker = {
424 			.magic =	cpu_to_je16(JFFS2_MAGIC_BITMASK),
425 			.nodetype =	cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER),
426 			.totlen =	cpu_to_je32(c->cleanmarker_size)
427 		};
428 
429 		jffs2_prealloc_raw_node_refs(c, jeb, 1);
430 
431 		marker.hdr_crc = cpu_to_je32(crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4));
432 
433 		vecs[0].iov_base = (unsigned char *) &marker;
434 		vecs[0].iov_len = sizeof(marker);
435 		ret = jffs2_flash_direct_writev(c, vecs, 1, jeb->offset, &retlen);
436 
437 		if (ret || retlen != sizeof(marker)) {
438 			if (ret)
439 				pr_warn("Write clean marker to block at 0x%08x failed: %d\n",
440 				       jeb->offset, ret);
441 			else
442 				pr_warn("Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
443 				       jeb->offset, sizeof(marker), retlen);
444 
445 			goto filebad;
446 		}
447 	}
448 	/* Everything else got zeroed before the erase */
449 	jeb->free_size = c->sector_size;
450 
451 	mutex_lock(&c->erase_free_sem);
452 	spin_lock(&c->erase_completion_lock);
453 
454 	c->erasing_size -= c->sector_size;
455 	c->free_size += c->sector_size;
456 
457 	/* Account for cleanmarker now, if it's in-band */
458 	if (c->cleanmarker_size && !jffs2_cleanmarker_oob(c))
459 		jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
460 
461 	list_move_tail(&jeb->list, &c->free_list);
462 	c->nr_erasing_blocks--;
463 	c->nr_free_blocks++;
464 
465 	jffs2_dbg_acct_sanity_check_nolock(c, jeb);
466 	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
467 
468 	spin_unlock(&c->erase_completion_lock);
469 	mutex_unlock(&c->erase_free_sem);
470 	wake_up(&c->erase_wait);
471 	return;
472 
473 filebad:
474 	jffs2_erase_failed(c, jeb, bad_offset);
475 	return;
476 
477 refile:
478 	/* Stick it back on the list from whence it came and come back later */
479 	mutex_lock(&c->erase_free_sem);
480 	spin_lock(&c->erase_completion_lock);
481 	jffs2_garbage_collect_trigger(c);
482 	list_move(&jeb->list, &c->erase_complete_list);
483 	spin_unlock(&c->erase_completion_lock);
484 	mutex_unlock(&c->erase_free_sem);
485 	return;
486 }
487