Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu
[safe/jmp/linux-2.6] / fs / jffs2 / erase.c
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright © 2001-2007 Red Hat, Inc.
5  *
6  * Created by David Woodhouse <dwmw2@infradead.org>
7  *
8  * For licensing information, see the file 'LICENCE' in this directory.
9  *
10  */
11
12 #include <linux/kernel.h>
13 #include <linux/slab.h>
14 #include <linux/mtd/mtd.h>
15 #include <linux/compiler.h>
16 #include <linux/crc32.h>
17 #include <linux/sched.h>
18 #include <linux/pagemap.h>
19 #include "nodelist.h"
20
21 struct erase_priv_struct {
22         struct jffs2_eraseblock *jeb;
23         struct jffs2_sb_info *c;
24 };
25
26 #ifndef __ECOS
27 static void jffs2_erase_callback(struct erase_info *);
28 #endif
29 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset);
30 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
31 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
32
33 static void jffs2_erase_block(struct jffs2_sb_info *c,
34                               struct jffs2_eraseblock *jeb)
35 {
36         int ret;
37         uint32_t bad_offset;
38 #ifdef __ECOS
39        ret = jffs2_flash_erase(c, jeb);
40        if (!ret) {
41                jffs2_erase_succeeded(c, jeb);
42                return;
43        }
44        bad_offset = jeb->offset;
45 #else /* Linux */
46         struct erase_info *instr;
47
48         D1(printk(KERN_DEBUG "jffs2_erase_block(): erase block %#08x (range %#08x-%#08x)\n",
49                                 jeb->offset, jeb->offset, jeb->offset + c->sector_size));
50         instr = kmalloc(sizeof(struct erase_info) + sizeof(struct erase_priv_struct), GFP_KERNEL);
51         if (!instr) {
52                 printk(KERN_WARNING "kmalloc for struct erase_info in jffs2_erase_block failed. Refiling block for later\n");
53                 mutex_lock(&c->erase_free_sem);
54                 spin_lock(&c->erase_completion_lock);
55                 list_move(&jeb->list, &c->erase_pending_list);
56                 c->erasing_size -= c->sector_size;
57                 c->dirty_size += c->sector_size;
58                 jeb->dirty_size = c->sector_size;
59                 spin_unlock(&c->erase_completion_lock);
60                 mutex_unlock(&c->erase_free_sem);
61                 return;
62         }
63
64         memset(instr, 0, sizeof(*instr));
65
66         instr->mtd = c->mtd;
67         instr->addr = jeb->offset;
68         instr->len = c->sector_size;
69         instr->callback = jffs2_erase_callback;
70         instr->priv = (unsigned long)(&instr[1]);
71         instr->fail_addr = MTD_FAIL_ADDR_UNKNOWN;
72
73         ((struct erase_priv_struct *)instr->priv)->jeb = jeb;
74         ((struct erase_priv_struct *)instr->priv)->c = c;
75
76         ret = c->mtd->erase(c->mtd, instr);
77         if (!ret)
78                 return;
79
80         bad_offset = instr->fail_addr;
81         kfree(instr);
82 #endif /* __ECOS */
83
84         if (ret == -ENOMEM || ret == -EAGAIN) {
85                 /* Erase failed immediately. Refile it on the list */
86                 D1(printk(KERN_DEBUG "Erase at 0x%08x failed: %d. Refiling on erase_pending_list\n", jeb->offset, ret));
87                 mutex_lock(&c->erase_free_sem);
88                 spin_lock(&c->erase_completion_lock);
89                 list_move(&jeb->list, &c->erase_pending_list);
90                 c->erasing_size -= c->sector_size;
91                 c->dirty_size += c->sector_size;
92                 jeb->dirty_size = c->sector_size;
93                 spin_unlock(&c->erase_completion_lock);
94                 mutex_unlock(&c->erase_free_sem);
95                 return;
96         }
97
98         if (ret == -EROFS)
99                 printk(KERN_WARNING "Erase at 0x%08x failed immediately: -EROFS. Is the sector locked?\n", jeb->offset);
100         else
101                 printk(KERN_WARNING "Erase at 0x%08x failed immediately: errno %d\n", jeb->offset, ret);
102
103         jffs2_erase_failed(c, jeb, bad_offset);
104 }
105
106 int jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count)
107 {
108         struct jffs2_eraseblock *jeb;
109         int work_done = 0;
110
111         mutex_lock(&c->erase_free_sem);
112
113         spin_lock(&c->erase_completion_lock);
114
115         while (!list_empty(&c->erase_complete_list) ||
116                !list_empty(&c->erase_pending_list)) {
117
118                 if (!list_empty(&c->erase_complete_list)) {
119                         jeb = list_entry(c->erase_complete_list.next, struct jffs2_eraseblock, list);
120                         list_move(&jeb->list, &c->erase_checking_list);
121                         spin_unlock(&c->erase_completion_lock);
122                         mutex_unlock(&c->erase_free_sem);
123                         jffs2_mark_erased_block(c, jeb);
124
125                         work_done++;
126                         if (!--count) {
127                                 D1(printk(KERN_DEBUG "Count reached. jffs2_erase_pending_blocks leaving\n"));
128                                 goto done;
129                         }
130
131                 } else if (!list_empty(&c->erase_pending_list)) {
132                         jeb = list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list);
133                         D1(printk(KERN_DEBUG "Starting erase of pending block 0x%08x\n", jeb->offset));
134                         list_del(&jeb->list);
135                         c->erasing_size += c->sector_size;
136                         c->wasted_size -= jeb->wasted_size;
137                         c->free_size -= jeb->free_size;
138                         c->used_size -= jeb->used_size;
139                         c->dirty_size -= jeb->dirty_size;
140                         jeb->wasted_size = jeb->used_size = jeb->dirty_size = jeb->free_size = 0;
141                         jffs2_free_jeb_node_refs(c, jeb);
142                         list_add(&jeb->list, &c->erasing_list);
143                         spin_unlock(&c->erase_completion_lock);
144                         mutex_unlock(&c->erase_free_sem);
145
146                         jffs2_erase_block(c, jeb);
147
148                 } else {
149                         BUG();
150                 }
151
152                 /* Be nice */
153                 yield();
154                 mutex_lock(&c->erase_free_sem);
155                 spin_lock(&c->erase_completion_lock);
156         }
157
158         spin_unlock(&c->erase_completion_lock);
159         mutex_unlock(&c->erase_free_sem);
160  done:
161         D1(printk(KERN_DEBUG "jffs2_erase_pending_blocks completed\n"));
162         return work_done;
163 }
164
165 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
166 {
167         D1(printk(KERN_DEBUG "Erase completed successfully at 0x%08x\n", jeb->offset));
168         mutex_lock(&c->erase_free_sem);
169         spin_lock(&c->erase_completion_lock);
170         list_move_tail(&jeb->list, &c->erase_complete_list);
171         /* Wake the GC thread to mark them clean */
172         jffs2_garbage_collect_trigger(c);
173         spin_unlock(&c->erase_completion_lock);
174         mutex_unlock(&c->erase_free_sem);
175         wake_up(&c->erase_wait);
176 }
177
178 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset)
179 {
180         /* For NAND, if the failure did not occur at the device level for a
181            specific physical page, don't bother updating the bad block table. */
182         if (jffs2_cleanmarker_oob(c) && (bad_offset != (uint32_t)MTD_FAIL_ADDR_UNKNOWN)) {
183                 /* We had a device-level failure to erase.  Let's see if we've
184                    failed too many times. */
185                 if (!jffs2_write_nand_badblock(c, jeb, bad_offset)) {
186                         /* We'd like to give this block another try. */
187                         mutex_lock(&c->erase_free_sem);
188                         spin_lock(&c->erase_completion_lock);
189                         list_move(&jeb->list, &c->erase_pending_list);
190                         c->erasing_size -= c->sector_size;
191                         c->dirty_size += c->sector_size;
192                         jeb->dirty_size = c->sector_size;
193                         spin_unlock(&c->erase_completion_lock);
194                         mutex_unlock(&c->erase_free_sem);
195                         return;
196                 }
197         }
198
199         mutex_lock(&c->erase_free_sem);
200         spin_lock(&c->erase_completion_lock);
201         c->erasing_size -= c->sector_size;
202         c->bad_size += c->sector_size;
203         list_move(&jeb->list, &c->bad_list);
204         c->nr_erasing_blocks--;
205         spin_unlock(&c->erase_completion_lock);
206         mutex_unlock(&c->erase_free_sem);
207         wake_up(&c->erase_wait);
208 }
209
210 #ifndef __ECOS
211 static void jffs2_erase_callback(struct erase_info *instr)
212 {
213         struct erase_priv_struct *priv = (void *)instr->priv;
214
215         if(instr->state != MTD_ERASE_DONE) {
216                 printk(KERN_WARNING "Erase at 0x%08llx finished, but state != MTD_ERASE_DONE. State is 0x%x instead.\n",
217                         (unsigned long long)instr->addr, instr->state);
218                 jffs2_erase_failed(priv->c, priv->jeb, instr->fail_addr);
219         } else {
220                 jffs2_erase_succeeded(priv->c, priv->jeb);
221         }
222         kfree(instr);
223 }
224 #endif /* !__ECOS */
225
226 /* Hmmm. Maybe we should accept the extra space it takes and make
227    this a standard doubly-linked list? */
228 static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c,
229                         struct jffs2_raw_node_ref *ref, struct jffs2_eraseblock *jeb)
230 {
231         struct jffs2_inode_cache *ic = NULL;
232         struct jffs2_raw_node_ref **prev;
233
234         prev = &ref->next_in_ino;
235
236         /* Walk the inode's list once, removing any nodes from this eraseblock */
237         while (1) {
238                 if (!(*prev)->next_in_ino) {
239                         /* We're looking at the jffs2_inode_cache, which is
240                            at the end of the linked list. Stash it and continue
241                            from the beginning of the list */
242                         ic = (struct jffs2_inode_cache *)(*prev);
243                         prev = &ic->nodes;
244                         continue;
245                 }
246
247                 if (SECTOR_ADDR((*prev)->flash_offset) == jeb->offset) {
248                         /* It's in the block we're erasing */
249                         struct jffs2_raw_node_ref *this;
250
251                         this = *prev;
252                         *prev = this->next_in_ino;
253                         this->next_in_ino = NULL;
254
255                         if (this == ref)
256                                 break;
257
258                         continue;
259                 }
260                 /* Not to be deleted. Skip */
261                 prev = &((*prev)->next_in_ino);
262         }
263
264         /* PARANOIA */
265         if (!ic) {
266                 JFFS2_WARNING("inode_cache/xattr_datum/xattr_ref"
267                               " not found in remove_node_refs()!!\n");
268                 return;
269         }
270
271         D1(printk(KERN_DEBUG "Removed nodes in range 0x%08x-0x%08x from ino #%u\n",
272                   jeb->offset, jeb->offset + c->sector_size, ic->ino));
273
274         D2({
275                 int i=0;
276                 struct jffs2_raw_node_ref *this;
277                 printk(KERN_DEBUG "After remove_node_refs_from_ino_list: \n");
278
279                 this = ic->nodes;
280
281                 printk(KERN_DEBUG);
282                 while(this) {
283                         printk(KERN_CONT "0x%08x(%d)->",
284                                ref_offset(this), ref_flags(this));
285                         if (++i == 5) {
286                                 printk(KERN_DEBUG);
287                                 i=0;
288                         }
289                         this = this->next_in_ino;
290                 }
291                 printk(KERN_CONT "\n");
292         });
293
294         switch (ic->class) {
295 #ifdef CONFIG_JFFS2_FS_XATTR
296                 case RAWNODE_CLASS_XATTR_DATUM:
297                         jffs2_release_xattr_datum(c, (struct jffs2_xattr_datum *)ic);
298                         break;
299                 case RAWNODE_CLASS_XATTR_REF:
300                         jffs2_release_xattr_ref(c, (struct jffs2_xattr_ref *)ic);
301                         break;
302 #endif
303                 default:
304                         if (ic->nodes == (void *)ic && ic->pino_nlink == 0)
305                                 jffs2_del_ino_cache(c, ic);
306         }
307 }
308
309 void jffs2_free_jeb_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
310 {
311         struct jffs2_raw_node_ref *block, *ref;
312         D1(printk(KERN_DEBUG "Freeing all node refs for eraseblock offset 0x%08x\n", jeb->offset));
313
314         block = ref = jeb->first_node;
315
316         while (ref) {
317                 if (ref->flash_offset == REF_LINK_NODE) {
318                         ref = ref->next_in_ino;
319                         jffs2_free_refblock(block);
320                         block = ref;
321                         continue;
322                 }
323                 if (ref->flash_offset != REF_EMPTY_NODE && ref->next_in_ino)
324                         jffs2_remove_node_refs_from_ino_list(c, ref, jeb);
325                 /* else it was a non-inode node or already removed, so don't bother */
326
327                 ref++;
328         }
329         jeb->first_node = jeb->last_node = NULL;
330 }
331
332 static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t *bad_offset)
333 {
334         void *ebuf;
335         uint32_t ofs;
336         size_t retlen;
337         int ret = -EIO;
338
339         if (c->mtd->point) {
340                 unsigned long *wordebuf;
341
342                 ret = c->mtd->point(c->mtd, jeb->offset, c->sector_size,
343                                     &retlen, &ebuf, NULL);
344                 if (ret) {
345                         D1(printk(KERN_DEBUG "MTD point failed %d\n", ret));
346                         goto do_flash_read;
347                 }
348                 if (retlen < c->sector_size) {
349                         /* Don't muck about if it won't let us point to the whole erase sector */
350                         D1(printk(KERN_DEBUG "MTD point returned len too short: 0x%zx\n", retlen));
351                         c->mtd->unpoint(c->mtd, jeb->offset, retlen);
352                         goto do_flash_read;
353                 }
354                 wordebuf = ebuf-sizeof(*wordebuf);
355                 retlen /= sizeof(*wordebuf);
356                 do {
357                    if (*++wordebuf != ~0)
358                            break;
359                 } while(--retlen);
360                 c->mtd->unpoint(c->mtd, jeb->offset, c->sector_size);
361                 if (retlen) {
362                         printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08tx\n",
363                                *wordebuf, jeb->offset + c->sector_size-retlen*sizeof(*wordebuf));
364                         return -EIO;
365                 }
366                 return 0;
367         }
368  do_flash_read:
369         ebuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
370         if (!ebuf) {
371                 printk(KERN_WARNING "Failed to allocate page buffer for verifying erase at 0x%08x. Refiling\n", jeb->offset);
372                 return -EAGAIN;
373         }
374
375         D1(printk(KERN_DEBUG "Verifying erase at 0x%08x\n", jeb->offset));
376
377         for (ofs = jeb->offset; ofs < jeb->offset + c->sector_size; ) {
378                 uint32_t readlen = min((uint32_t)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
379                 int i;
380
381                 *bad_offset = ofs;
382
383                 ret = c->mtd->read(c->mtd, ofs, readlen, &retlen, ebuf);
384                 if (ret) {
385                         printk(KERN_WARNING "Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n", ofs, ret);
386                         ret = -EIO;
387                         goto fail;
388                 }
389                 if (retlen != readlen) {
390                         printk(KERN_WARNING "Short read from newly-erased block at 0x%08x. Wanted %d, got %zd\n", ofs, readlen, retlen);
391                         ret = -EIO;
392                         goto fail;
393                 }
394                 for (i=0; i<readlen; i += sizeof(unsigned long)) {
395                         /* It's OK. We know it's properly aligned */
396                         unsigned long *datum = ebuf + i;
397                         if (*datum + 1) {
398                                 *bad_offset += i;
399                                 printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08x\n", *datum, *bad_offset);
400                                 ret = -EIO;
401                                 goto fail;
402                         }
403                 }
404                 ofs += readlen;
405                 cond_resched();
406         }
407         ret = 0;
408 fail:
409         kfree(ebuf);
410         return ret;
411 }
412
413 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
414 {
415         size_t retlen;
416         int ret;
417         uint32_t uninitialized_var(bad_offset);
418
419         switch (jffs2_block_check_erase(c, jeb, &bad_offset)) {
420         case -EAGAIN:   goto refile;
421         case -EIO:      goto filebad;
422         }
423
424         /* Write the erase complete marker */
425         D1(printk(KERN_DEBUG "Writing erased marker to block at 0x%08x\n", jeb->offset));
426         bad_offset = jeb->offset;
427
428         /* Cleanmarker in oob area or no cleanmarker at all ? */
429         if (jffs2_cleanmarker_oob(c) || c->cleanmarker_size == 0) {
430
431                 if (jffs2_cleanmarker_oob(c)) {
432                         if (jffs2_write_nand_cleanmarker(c, jeb))
433                                 goto filebad;
434                 }
435         } else {
436
437                 struct kvec vecs[1];
438                 struct jffs2_unknown_node marker = {
439                         .magic =        cpu_to_je16(JFFS2_MAGIC_BITMASK),
440                         .nodetype =     cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER),
441                         .totlen =       cpu_to_je32(c->cleanmarker_size)
442                 };
443
444                 jffs2_prealloc_raw_node_refs(c, jeb, 1);
445
446                 marker.hdr_crc = cpu_to_je32(crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4));
447
448                 vecs[0].iov_base = (unsigned char *) &marker;
449                 vecs[0].iov_len = sizeof(marker);
450                 ret = jffs2_flash_direct_writev(c, vecs, 1, jeb->offset, &retlen);
451
452                 if (ret || retlen != sizeof(marker)) {
453                         if (ret)
454                                 printk(KERN_WARNING "Write clean marker to block at 0x%08x failed: %d\n",
455                                        jeb->offset, ret);
456                         else
457                                 printk(KERN_WARNING "Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
458                                        jeb->offset, sizeof(marker), retlen);
459
460                         goto filebad;
461                 }
462         }
463         /* Everything else got zeroed before the erase */
464         jeb->free_size = c->sector_size;
465
466         mutex_lock(&c->erase_free_sem);
467         spin_lock(&c->erase_completion_lock);
468
469         c->erasing_size -= c->sector_size;
470         c->free_size += c->sector_size;
471
472         /* Account for cleanmarker now, if it's in-band */
473         if (c->cleanmarker_size && !jffs2_cleanmarker_oob(c))
474                 jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
475
476         list_move_tail(&jeb->list, &c->free_list);
477         c->nr_erasing_blocks--;
478         c->nr_free_blocks++;
479
480         jffs2_dbg_acct_sanity_check_nolock(c, jeb);
481         jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
482
483         spin_unlock(&c->erase_completion_lock);
484         mutex_unlock(&c->erase_free_sem);
485         wake_up(&c->erase_wait);
486         return;
487
488 filebad:
489         jffs2_erase_failed(c, jeb, bad_offset);
490         return;
491
492 refile:
493         /* Stick it back on the list from whence it came and come back later */
494         mutex_lock(&c->erase_free_sem);
495         spin_lock(&c->erase_completion_lock);
496         jffs2_garbage_collect_trigger(c);
497         list_move(&jeb->list, &c->erase_complete_list);
498         spin_unlock(&c->erase_completion_lock);
499         mutex_unlock(&c->erase_free_sem);
500         return;
501 }