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
24static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset);
25static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
26static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
27
28static 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
99int 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
159static 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
172static 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? */
206static 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
287void 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
311static 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;
393fail:
394	kfree(ebuf);
395	return ret;
396}
397
398static 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
473filebad:
474	jffs2_erase_failed(c, jeb, bad_offset);
475	return;
476
477refile:
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