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 = kmalloc(sizeof(struct erase_info), GFP_KERNEL);
47 	if (!instr) {
48 		pr_warn("kmalloc 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 	memset(instr, 0, sizeof(*instr));
61 
62 	instr->addr = jeb->offset;
63 	instr->len = c->sector_size;
64 
65 	ret = mtd_erase(c->mtd, instr);
66 	if (!ret) {
67 		jffs2_erase_succeeded(c, jeb);
68 		kfree(instr);
69 		return;
70 	}
71 
72 	bad_offset = instr->fail_addr;
73 	kfree(instr);
74 #endif /* __ECOS */
75 
76 	if (ret == -ENOMEM || ret == -EAGAIN) {
77 		/* Erase failed immediately. Refile it on the list */
78 		jffs2_dbg(1, "Erase at 0x%08x failed: %d. Refiling on erase_pending_list\n",
79 			  jeb->offset, ret);
80 		mutex_lock(&c->erase_free_sem);
81 		spin_lock(&c->erase_completion_lock);
82 		list_move(&jeb->list, &c->erase_pending_list);
83 		c->erasing_size -= c->sector_size;
84 		c->dirty_size += c->sector_size;
85 		jeb->dirty_size = c->sector_size;
86 		spin_unlock(&c->erase_completion_lock);
87 		mutex_unlock(&c->erase_free_sem);
88 		return;
89 	}
90 
91 	if (ret == -EROFS)
92 		pr_warn("Erase at 0x%08x failed immediately: -EROFS. Is the sector locked?\n",
93 			jeb->offset);
94 	else
95 		pr_warn("Erase at 0x%08x failed immediately: errno %d\n",
96 			jeb->offset, ret);
97 
98 	jffs2_erase_failed(c, jeb, bad_offset);
99 }
100 
jffs2_erase_pending_blocks(struct jffs2_sb_info * c,int count)101 int jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count)
102 {
103 	struct jffs2_eraseblock *jeb;
104 	int work_done = 0;
105 
106 	mutex_lock(&c->erase_free_sem);
107 
108 	spin_lock(&c->erase_completion_lock);
109 
110 	while (!list_empty(&c->erase_complete_list) ||
111 	       !list_empty(&c->erase_pending_list)) {
112 
113 		if (!list_empty(&c->erase_complete_list)) {
114 			jeb = list_entry(c->erase_complete_list.next, struct jffs2_eraseblock, list);
115 			list_move(&jeb->list, &c->erase_checking_list);
116 			spin_unlock(&c->erase_completion_lock);
117 			mutex_unlock(&c->erase_free_sem);
118 			jffs2_mark_erased_block(c, jeb);
119 
120 			work_done++;
121 			if (!--count) {
122 				jffs2_dbg(1, "Count reached. jffs2_erase_pending_blocks leaving\n");
123 				goto done;
124 			}
125 
126 		} else if (!list_empty(&c->erase_pending_list)) {
127 			jeb = list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list);
128 			jffs2_dbg(1, "Starting erase of pending block 0x%08x\n",
129 				  jeb->offset);
130 			list_del(&jeb->list);
131 			c->erasing_size += c->sector_size;
132 			c->wasted_size -= jeb->wasted_size;
133 			c->free_size -= jeb->free_size;
134 			c->used_size -= jeb->used_size;
135 			c->dirty_size -= jeb->dirty_size;
136 			jeb->wasted_size = jeb->used_size = jeb->dirty_size = jeb->free_size = 0;
137 			jffs2_free_jeb_node_refs(c, jeb);
138 			list_add(&jeb->list, &c->erasing_list);
139 			spin_unlock(&c->erase_completion_lock);
140 			mutex_unlock(&c->erase_free_sem);
141 
142 			jffs2_erase_block(c, jeb);
143 
144 		} else {
145 			BUG();
146 		}
147 
148 		/* Be nice */
149 		cond_resched();
150 		mutex_lock(&c->erase_free_sem);
151 		spin_lock(&c->erase_completion_lock);
152 	}
153 
154 	spin_unlock(&c->erase_completion_lock);
155 	mutex_unlock(&c->erase_free_sem);
156  done:
157 	jffs2_dbg(1, "jffs2_erase_pending_blocks completed\n");
158 	return work_done;
159 }
160 
jffs2_erase_succeeded(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)161 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
162 {
163 	jffs2_dbg(1, "Erase completed successfully at 0x%08x\n", jeb->offset);
164 	mutex_lock(&c->erase_free_sem);
165 	spin_lock(&c->erase_completion_lock);
166 	list_move_tail(&jeb->list, &c->erase_complete_list);
167 	/* Wake the GC thread to mark them clean */
168 	jffs2_garbage_collect_trigger(c);
169 	spin_unlock(&c->erase_completion_lock);
170 	mutex_unlock(&c->erase_free_sem);
171 	wake_up(&c->erase_wait);
172 }
173 
jffs2_erase_failed(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb,uint32_t bad_offset)174 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset)
175 {
176 	/* For NAND, if the failure did not occur at the device level for a
177 	   specific physical page, don't bother updating the bad block table. */
178 	if (jffs2_cleanmarker_oob(c) && (bad_offset != (uint32_t)MTD_FAIL_ADDR_UNKNOWN)) {
179 		/* We had a device-level failure to erase.  Let's see if we've
180 		   failed too many times. */
181 		if (!jffs2_write_nand_badblock(c, jeb, bad_offset)) {
182 			/* We'd like to give this block another try. */
183 			mutex_lock(&c->erase_free_sem);
184 			spin_lock(&c->erase_completion_lock);
185 			list_move(&jeb->list, &c->erase_pending_list);
186 			c->erasing_size -= c->sector_size;
187 			c->dirty_size += c->sector_size;
188 			jeb->dirty_size = c->sector_size;
189 			spin_unlock(&c->erase_completion_lock);
190 			mutex_unlock(&c->erase_free_sem);
191 			return;
192 		}
193 	}
194 
195 	mutex_lock(&c->erase_free_sem);
196 	spin_lock(&c->erase_completion_lock);
197 	c->erasing_size -= c->sector_size;
198 	c->bad_size += c->sector_size;
199 	list_move(&jeb->list, &c->bad_list);
200 	c->nr_erasing_blocks--;
201 	spin_unlock(&c->erase_completion_lock);
202 	mutex_unlock(&c->erase_free_sem);
203 	wake_up(&c->erase_wait);
204 }
205 
206 /* Hmmm. Maybe we should accept the extra space it takes and make
207    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)208 static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c,
209 			struct jffs2_raw_node_ref *ref, struct jffs2_eraseblock *jeb)
210 {
211 	struct jffs2_inode_cache *ic = NULL;
212 	struct jffs2_raw_node_ref **prev;
213 
214 	prev = &ref->next_in_ino;
215 
216 	/* Walk the inode's list once, removing any nodes from this eraseblock */
217 	while (1) {
218 		if (!(*prev)->next_in_ino) {
219 			/* We're looking at the jffs2_inode_cache, which is
220 			   at the end of the linked list. Stash it and continue
221 			   from the beginning of the list */
222 			ic = (struct jffs2_inode_cache *)(*prev);
223 			prev = &ic->nodes;
224 			continue;
225 		}
226 
227 		if (SECTOR_ADDR((*prev)->flash_offset) == jeb->offset) {
228 			/* It's in the block we're erasing */
229 			struct jffs2_raw_node_ref *this;
230 
231 			this = *prev;
232 			*prev = this->next_in_ino;
233 			this->next_in_ino = NULL;
234 
235 			if (this == ref)
236 				break;
237 
238 			continue;
239 		}
240 		/* Not to be deleted. Skip */
241 		prev = &((*prev)->next_in_ino);
242 	}
243 
244 	/* PARANOIA */
245 	if (!ic) {
246 		JFFS2_WARNING("inode_cache/xattr_datum/xattr_ref"
247 			      " not found in remove_node_refs()!!\n");
248 		return;
249 	}
250 
251 	jffs2_dbg(1, "Removed nodes in range 0x%08x-0x%08x from ino #%u\n",
252 		  jeb->offset, jeb->offset + c->sector_size, ic->ino);
253 
254 	D2({
255 		int i=0;
256 		struct jffs2_raw_node_ref *this;
257 		printk(KERN_DEBUG "After remove_node_refs_from_ino_list: \n");
258 
259 		this = ic->nodes;
260 
261 		printk(KERN_DEBUG);
262 		while(this) {
263 			pr_cont("0x%08x(%d)->",
264 			       ref_offset(this), ref_flags(this));
265 			if (++i == 5) {
266 				printk(KERN_DEBUG);
267 				i=0;
268 			}
269 			this = this->next_in_ino;
270 		}
271 		pr_cont("\n");
272 	});
273 
274 	switch (ic->class) {
275 #ifdef CONFIG_JFFS2_FS_XATTR
276 		case RAWNODE_CLASS_XATTR_DATUM:
277 			jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic);
278 			break;
279 		case RAWNODE_CLASS_XATTR_REF:
280 			jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic);
281 			break;
282 #endif
283 		default:
284 			if (ic->nodes == (void *)ic && ic->pino_nlink == 0)
285 				jffs2_del_ino_cache(c, ic);
286 	}
287 }
288 
jffs2_free_jeb_node_refs(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)289 void jffs2_free_jeb_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
290 {
291 	struct jffs2_raw_node_ref *block, *ref;
292 	jffs2_dbg(1, "Freeing all node refs for eraseblock offset 0x%08x\n",
293 		  jeb->offset);
294 
295 	block = ref = jeb->first_node;
296 
297 	while (ref) {
298 		if (ref->flash_offset == REF_LINK_NODE) {
299 			ref = ref->next_in_ino;
300 			jffs2_free_refblock(block);
301 			block = ref;
302 			continue;
303 		}
304 		if (ref->flash_offset != REF_EMPTY_NODE && ref->next_in_ino)
305 			jffs2_remove_node_refs_from_ino_list(c, ref, jeb);
306 		/* else it was a non-inode node or already removed, so don't bother */
307 
308 		ref++;
309 	}
310 	jeb->first_node = jeb->last_node = NULL;
311 }
312 
jffs2_block_check_erase(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb,uint32_t * bad_offset)313 static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t *bad_offset)
314 {
315 	void *ebuf;
316 	uint32_t ofs;
317 	size_t retlen;
318 	int ret;
319 	unsigned long *wordebuf;
320 
321 	ret = mtd_point(c->mtd, jeb->offset, c->sector_size, &retlen,
322 			&ebuf, NULL);
323 	if (ret != -EOPNOTSUPP) {
324 		if (ret) {
325 			jffs2_dbg(1, "MTD point failed %d\n", ret);
326 			goto do_flash_read;
327 		}
328 		if (retlen < c->sector_size) {
329 			/* Don't muck about if it won't let us point to the whole erase sector */
330 			jffs2_dbg(1, "MTD point returned len too short: 0x%zx\n",
331 				  retlen);
332 			mtd_unpoint(c->mtd, jeb->offset, retlen);
333 			goto do_flash_read;
334 		}
335 		wordebuf = ebuf-sizeof(*wordebuf);
336 		retlen /= sizeof(*wordebuf);
337 		do {
338 		   if (*++wordebuf != ~0)
339 			   break;
340 		} while(--retlen);
341 		mtd_unpoint(c->mtd, jeb->offset, c->sector_size);
342 		if (retlen) {
343 			pr_warn("Newly-erased block contained word 0x%lx at offset 0x%08tx\n",
344 				*wordebuf,
345 				jeb->offset +
346 				c->sector_size-retlen * sizeof(*wordebuf));
347 			return -EIO;
348 		}
349 		return 0;
350 	}
351  do_flash_read:
352 	ebuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
353 	if (!ebuf) {
354 		pr_warn("Failed to allocate page buffer for verifying erase at 0x%08x. Refiling\n",
355 			jeb->offset);
356 		return -EAGAIN;
357 	}
358 
359 	jffs2_dbg(1, "Verifying erase at 0x%08x\n", jeb->offset);
360 
361 	for (ofs = jeb->offset; ofs < jeb->offset + c->sector_size; ) {
362 		uint32_t readlen = min((uint32_t)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
363 		int i;
364 
365 		*bad_offset = ofs;
366 
367 		ret = mtd_read(c->mtd, ofs, readlen, &retlen, ebuf);
368 		if (ret) {
369 			pr_warn("Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n",
370 				ofs, ret);
371 			ret = -EIO;
372 			goto fail;
373 		}
374 		if (retlen != readlen) {
375 			pr_warn("Short read from newly-erased block at 0x%08x. Wanted %d, got %zd\n",
376 				ofs, readlen, retlen);
377 			ret = -EIO;
378 			goto fail;
379 		}
380 		for (i=0; i<readlen; i += sizeof(unsigned long)) {
381 			/* It's OK. We know it's properly aligned */
382 			unsigned long *datum = ebuf + i;
383 			if (*datum + 1) {
384 				*bad_offset += i;
385 				pr_warn("Newly-erased block contained word 0x%lx at offset 0x%08x\n",
386 					*datum, *bad_offset);
387 				ret = -EIO;
388 				goto fail;
389 			}
390 		}
391 		ofs += readlen;
392 		cond_resched();
393 	}
394 	ret = 0;
395 fail:
396 	kfree(ebuf);
397 	return ret;
398 }
399 
jffs2_mark_erased_block(struct jffs2_sb_info * c,struct jffs2_eraseblock * jeb)400 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
401 {
402 	size_t retlen;
403 	int ret;
404 	uint32_t uninitialized_var(bad_offset);
405 
406 	switch (jffs2_block_check_erase(c, jeb, &bad_offset)) {
407 	case -EAGAIN:	goto refile;
408 	case -EIO:	goto filebad;
409 	}
410 
411 	/* Write the erase complete marker */
412 	jffs2_dbg(1, "Writing erased marker to block at 0x%08x\n", jeb->offset);
413 	bad_offset = jeb->offset;
414 
415 	/* Cleanmarker in oob area or no cleanmarker at all ? */
416 	if (jffs2_cleanmarker_oob(c) || c->cleanmarker_size == 0) {
417 
418 		if (jffs2_cleanmarker_oob(c)) {
419 			if (jffs2_write_nand_cleanmarker(c, jeb))
420 				goto filebad;
421 		}
422 	} else {
423 
424 		struct kvec vecs[1];
425 		struct jffs2_unknown_node marker = {
426 			.magic =	cpu_to_je16(JFFS2_MAGIC_BITMASK),
427 			.nodetype =	cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER),
428 			.totlen =	cpu_to_je32(c->cleanmarker_size)
429 		};
430 
431 		jffs2_prealloc_raw_node_refs(c, jeb, 1);
432 
433 		marker.hdr_crc = cpu_to_je32(crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4));
434 
435 		vecs[0].iov_base = (unsigned char *) &marker;
436 		vecs[0].iov_len = sizeof(marker);
437 		ret = jffs2_flash_direct_writev(c, vecs, 1, jeb->offset, &retlen);
438 
439 		if (ret || retlen != sizeof(marker)) {
440 			if (ret)
441 				pr_warn("Write clean marker to block at 0x%08x failed: %d\n",
442 				       jeb->offset, ret);
443 			else
444 				pr_warn("Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
445 				       jeb->offset, sizeof(marker), retlen);
446 
447 			goto filebad;
448 		}
449 	}
450 	/* Everything else got zeroed before the erase */
451 	jeb->free_size = c->sector_size;
452 
453 	mutex_lock(&c->erase_free_sem);
454 	spin_lock(&c->erase_completion_lock);
455 
456 	c->erasing_size -= c->sector_size;
457 	c->free_size += c->sector_size;
458 
459 	/* Account for cleanmarker now, if it's in-band */
460 	if (c->cleanmarker_size && !jffs2_cleanmarker_oob(c))
461 		jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
462 
463 	list_move_tail(&jeb->list, &c->free_list);
464 	c->nr_erasing_blocks--;
465 	c->nr_free_blocks++;
466 
467 	jffs2_dbg_acct_sanity_check_nolock(c, jeb);
468 	jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
469 
470 	spin_unlock(&c->erase_completion_lock);
471 	mutex_unlock(&c->erase_free_sem);
472 	wake_up(&c->erase_wait);
473 	return;
474 
475 filebad:
476 	jffs2_erase_failed(c, jeb, bad_offset);
477 	return;
478 
479 refile:
480 	/* Stick it back on the list from whence it came and come back later */
481 	mutex_lock(&c->erase_free_sem);
482 	spin_lock(&c->erase_completion_lock);
483 	jffs2_garbage_collect_trigger(c);
484 	list_move(&jeb->list, &c->erase_complete_list);
485 	spin_unlock(&c->erase_completion_lock);
486 	mutex_unlock(&c->erase_free_sem);
487 	return;
488 }
489