Merge branch 'rio.b19' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/bird
[sfrench/cifs-2.6.git] / fs / jffs2 / erase.c
1 /*
2  * JFFS2 -- Journalling Flash File System, Version 2.
3  *
4  * Copyright (C) 2001-2003 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  * $Id: erase.c,v 1.85 2005/09/20 14:53:15 dedekind Exp $
11  *
12  */
13
14 #include <linux/kernel.h>
15 #include <linux/slab.h>
16 #include <linux/mtd/mtd.h>
17 #include <linux/compiler.h>
18 #include <linux/crc32.h>
19 #include <linux/sched.h>
20 #include <linux/pagemap.h>
21 #include "nodelist.h"
22
23 struct erase_priv_struct {
24         struct jffs2_eraseblock *jeb;
25         struct jffs2_sb_info *c;
26 };
27
28 #ifndef __ECOS
29 static void jffs2_erase_callback(struct erase_info *);
30 #endif
31 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset);
32 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
33 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb);
34
35 static void jffs2_erase_block(struct jffs2_sb_info *c,
36                               struct jffs2_eraseblock *jeb)
37 {
38         int ret;
39         uint32_t bad_offset;
40 #ifdef __ECOS
41        ret = jffs2_flash_erase(c, jeb);
42        if (!ret) {
43                jffs2_erase_succeeded(c, jeb);
44                return;
45        }
46        bad_offset = jeb->offset;
47 #else /* Linux */
48         struct erase_info *instr;
49
50         D1(printk(KERN_DEBUG "jffs2_erase_block(): erase block %#08x (range %#08x-%#08x)\n",
51                                 jeb->offset, jeb->offset, jeb->offset + c->sector_size));
52         instr = kmalloc(sizeof(struct erase_info) + sizeof(struct erase_priv_struct), GFP_KERNEL);
53         if (!instr) {
54                 printk(KERN_WARNING "kmalloc for struct erase_info in jffs2_erase_block failed. Refiling block for later\n");
55                 spin_lock(&c->erase_completion_lock);
56                 list_del(&jeb->list);
57                 list_add(&jeb->list, &c->erase_pending_list);
58                 c->erasing_size -= c->sector_size;
59                 c->dirty_size += c->sector_size;
60                 jeb->dirty_size = c->sector_size;
61                 spin_unlock(&c->erase_completion_lock);
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 = 0xffffffff;
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                 spin_lock(&c->erase_completion_lock);
89                 list_del(&jeb->list);
90                 list_add(&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                 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 void jffs2_erase_pending_blocks(struct jffs2_sb_info *c, int count)
107 {
108         struct jffs2_eraseblock *jeb;
109
110         down(&c->erase_free_sem);
111
112         spin_lock(&c->erase_completion_lock);
113
114         while (!list_empty(&c->erase_complete_list) ||
115                !list_empty(&c->erase_pending_list)) {
116
117                 if (!list_empty(&c->erase_complete_list)) {
118                         jeb = list_entry(c->erase_complete_list.next, struct jffs2_eraseblock, list);
119                         list_del(&jeb->list);
120                         spin_unlock(&c->erase_completion_lock);
121                         jffs2_mark_erased_block(c, jeb);
122
123                         if (!--count) {
124                                 D1(printk(KERN_DEBUG "Count reached. jffs2_erase_pending_blocks leaving\n"));
125                                 goto done;
126                         }
127
128                 } else if (!list_empty(&c->erase_pending_list)) {
129                         jeb = list_entry(c->erase_pending_list.next, struct jffs2_eraseblock, list);
130                         D1(printk(KERN_DEBUG "Starting erase of pending block 0x%08x\n", jeb->offset));
131                         list_del(&jeb->list);
132                         c->erasing_size += c->sector_size;
133                         c->wasted_size -= jeb->wasted_size;
134                         c->free_size -= jeb->free_size;
135                         c->used_size -= jeb->used_size;
136                         c->dirty_size -= jeb->dirty_size;
137                         jeb->wasted_size = jeb->used_size = jeb->dirty_size = jeb->free_size = 0;
138                         jffs2_free_jeb_node_refs(c, jeb);
139                         list_add(&jeb->list, &c->erasing_list);
140                         spin_unlock(&c->erase_completion_lock);
141
142                         jffs2_erase_block(c, jeb);
143
144                 } else {
145                         BUG();
146                 }
147
148                 /* Be nice */
149                 cond_resched();
150                 spin_lock(&c->erase_completion_lock);
151         }
152
153         spin_unlock(&c->erase_completion_lock);
154  done:
155         D1(printk(KERN_DEBUG "jffs2_erase_pending_blocks completed\n"));
156
157         up(&c->erase_free_sem);
158 }
159
160 static void jffs2_erase_succeeded(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
161 {
162         D1(printk(KERN_DEBUG "Erase completed successfully at 0x%08x\n", jeb->offset));
163         spin_lock(&c->erase_completion_lock);
164         list_del(&jeb->list);
165         list_add_tail(&jeb->list, &c->erase_complete_list);
166         spin_unlock(&c->erase_completion_lock);
167         /* Ensure that kupdated calls us again to mark them clean */
168         jffs2_erase_pending_trigger(c);
169 }
170
171 static void jffs2_erase_failed(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t bad_offset)
172 {
173         /* For NAND, if the failure did not occur at the device level for a
174            specific physical page, don't bother updating the bad block table. */
175         if (jffs2_cleanmarker_oob(c) && (bad_offset != 0xffffffff)) {
176                 /* We had a device-level failure to erase.  Let's see if we've
177                    failed too many times. */
178                 if (!jffs2_write_nand_badblock(c, jeb, bad_offset)) {
179                         /* We'd like to give this block another try. */
180                         spin_lock(&c->erase_completion_lock);
181                         list_del(&jeb->list);
182                         list_add(&jeb->list, &c->erase_pending_list);
183                         c->erasing_size -= c->sector_size;
184                         c->dirty_size += c->sector_size;
185                         jeb->dirty_size = c->sector_size;
186                         spin_unlock(&c->erase_completion_lock);
187                         return;
188                 }
189         }
190
191         spin_lock(&c->erase_completion_lock);
192         c->erasing_size -= c->sector_size;
193         c->bad_size += c->sector_size;
194         list_del(&jeb->list);
195         list_add(&jeb->list, &c->bad_list);
196         c->nr_erasing_blocks--;
197         spin_unlock(&c->erase_completion_lock);
198         wake_up(&c->erase_wait);
199 }
200
201 #ifndef __ECOS
202 static void jffs2_erase_callback(struct erase_info *instr)
203 {
204         struct erase_priv_struct *priv = (void *)instr->priv;
205
206         if(instr->state != MTD_ERASE_DONE) {
207                 printk(KERN_WARNING "Erase at 0x%08x finished, but state != MTD_ERASE_DONE. State is 0x%x instead.\n", instr->addr, instr->state);
208                 jffs2_erase_failed(priv->c, priv->jeb, instr->fail_addr);
209         } else {
210                 jffs2_erase_succeeded(priv->c, priv->jeb);
211         }
212         kfree(instr);
213 }
214 #endif /* !__ECOS */
215
216 /* Hmmm. Maybe we should accept the extra space it takes and make
217    this a standard doubly-linked list? */
218 static inline void jffs2_remove_node_refs_from_ino_list(struct jffs2_sb_info *c,
219                         struct jffs2_raw_node_ref *ref, struct jffs2_eraseblock *jeb)
220 {
221         struct jffs2_inode_cache *ic = NULL;
222         struct jffs2_raw_node_ref **prev;
223
224         prev = &ref->next_in_ino;
225
226         /* Walk the inode's list once, removing any nodes from this eraseblock */
227         while (1) {
228                 if (!(*prev)->next_in_ino) {
229                         /* We're looking at the jffs2_inode_cache, which is
230                            at the end of the linked list. Stash it and continue
231                            from the beginning of the list */
232                         ic = (struct jffs2_inode_cache *)(*prev);
233                         BUG_ON(ic->class != RAWNODE_CLASS_INODE_CACHE);
234                         prev = &ic->nodes;
235                         continue;
236                 }
237
238                 if (SECTOR_ADDR((*prev)->flash_offset) == jeb->offset) {
239                         /* It's in the block we're erasing */
240                         struct jffs2_raw_node_ref *this;
241
242                         this = *prev;
243                         *prev = this->next_in_ino;
244                         this->next_in_ino = NULL;
245
246                         if (this == ref)
247                                 break;
248
249                         continue;
250                 }
251                 /* Not to be deleted. Skip */
252                 prev = &((*prev)->next_in_ino);
253         }
254
255         /* PARANOIA */
256         if (!ic) {
257                 printk(KERN_WARNING "inode_cache not found in remove_node_refs()!!\n");
258                 return;
259         }
260
261         D1(printk(KERN_DEBUG "Removed nodes in range 0x%08x-0x%08x from ino #%u\n",
262                   jeb->offset, jeb->offset + c->sector_size, ic->ino));
263
264         D2({
265                 int i=0;
266                 struct jffs2_raw_node_ref *this;
267                 printk(KERN_DEBUG "After remove_node_refs_from_ino_list: \n" KERN_DEBUG);
268
269                 this = ic->nodes;
270
271                 while(this) {
272                         printk( "0x%08x(%d)->", ref_offset(this), ref_flags(this));
273                         if (++i == 5) {
274                                 printk("\n" KERN_DEBUG);
275                                 i=0;
276                         }
277                         this = this->next_in_ino;
278                 }
279                 printk("\n");
280         });
281
282         if (ic->nodes == (void *)ic && ic->nlink == 0)
283                 jffs2_del_ino_cache(c, ic);
284 }
285
286 void jffs2_free_jeb_node_refs(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
287 {
288         struct jffs2_raw_node_ref *block, *ref;
289         D1(printk(KERN_DEBUG "Freeing all node refs for eraseblock offset 0x%08x\n", jeb->offset));
290
291         block = ref = jeb->first_node;
292
293         while (ref) {
294                 if (ref->flash_offset == REF_LINK_NODE) {
295                         ref = ref->next_in_ino;
296                         jffs2_free_refblock(block);
297                         block = ref;
298                         continue;
299                 }
300                 if (ref->flash_offset != REF_EMPTY_NODE && ref->next_in_ino)
301                         jffs2_remove_node_refs_from_ino_list(c, ref, jeb);
302                 /* else it was a non-inode node or already removed, so don't bother */
303
304                 ref++;
305         }
306         jeb->first_node = jeb->last_node = NULL;
307 }
308
309 static int jffs2_block_check_erase(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb, uint32_t *bad_offset)
310 {
311         void *ebuf;
312         uint32_t ofs;
313         size_t retlen;
314         int ret = -EIO;
315
316         ebuf = kmalloc(PAGE_SIZE, GFP_KERNEL);
317         if (!ebuf) {
318                 printk(KERN_WARNING "Failed to allocate page buffer for verifying erase at 0x%08x. Refiling\n", jeb->offset);
319                 return -EAGAIN;
320         }
321
322         D1(printk(KERN_DEBUG "Verifying erase at 0x%08x\n", jeb->offset));
323
324         for (ofs = jeb->offset; ofs < jeb->offset + c->sector_size; ) {
325                 uint32_t readlen = min((uint32_t)PAGE_SIZE, jeb->offset + c->sector_size - ofs);
326                 int i;
327
328                 *bad_offset = ofs;
329
330                 ret = jffs2_flash_read(c, ofs, readlen, &retlen, ebuf);
331                 if (ret) {
332                         printk(KERN_WARNING "Read of newly-erased block at 0x%08x failed: %d. Putting on bad_list\n", ofs, ret);
333                         goto fail;
334                 }
335                 if (retlen != readlen) {
336                         printk(KERN_WARNING "Short read from newly-erased block at 0x%08x. Wanted %d, got %zd\n", ofs, readlen, retlen);
337                         goto fail;
338                 }
339                 for (i=0; i<readlen; i += sizeof(unsigned long)) {
340                         /* It's OK. We know it's properly aligned */
341                         unsigned long *datum = ebuf + i;
342                         if (*datum + 1) {
343                                 *bad_offset += i;
344                                 printk(KERN_WARNING "Newly-erased block contained word 0x%lx at offset 0x%08x\n", *datum, *bad_offset);
345                                 goto fail;
346                         }
347                 }
348                 ofs += readlen;
349                 cond_resched();
350         }
351         ret = 0;
352 fail:
353         kfree(ebuf);
354         return ret;
355 }
356
357 static void jffs2_mark_erased_block(struct jffs2_sb_info *c, struct jffs2_eraseblock *jeb)
358 {
359         size_t retlen;
360         int ret;
361         uint32_t bad_offset;
362
363         switch (jffs2_block_check_erase(c, jeb, &bad_offset)) {
364         case -EAGAIN:   goto refile;
365         case -EIO:      goto filebad;
366         }
367
368         /* Write the erase complete marker */
369         D1(printk(KERN_DEBUG "Writing erased marker to block at 0x%08x\n", jeb->offset));
370         bad_offset = jeb->offset;
371
372         /* Cleanmarker in oob area or no cleanmarker at all ? */
373         if (jffs2_cleanmarker_oob(c) || c->cleanmarker_size == 0) {
374
375                 if (jffs2_cleanmarker_oob(c)) {
376                         if (jffs2_write_nand_cleanmarker(c, jeb))
377                                 goto filebad;
378                 }
379
380                 /* Everything else got zeroed before the erase */
381                 jeb->free_size = c->sector_size;
382         } else {
383
384                 struct kvec vecs[1];
385                 struct jffs2_unknown_node marker = {
386                         .magic =        cpu_to_je16(JFFS2_MAGIC_BITMASK),
387                         .nodetype =     cpu_to_je16(JFFS2_NODETYPE_CLEANMARKER),
388                         .totlen =       cpu_to_je32(c->cleanmarker_size)
389                 };
390
391                 jffs2_prealloc_raw_node_refs(c, jeb, 1);
392
393                 marker.hdr_crc = cpu_to_je32(crc32(0, &marker, sizeof(struct jffs2_unknown_node)-4));
394
395                 vecs[0].iov_base = (unsigned char *) &marker;
396                 vecs[0].iov_len = sizeof(marker);
397                 ret = jffs2_flash_direct_writev(c, vecs, 1, jeb->offset, &retlen);
398
399                 if (ret || retlen != sizeof(marker)) {
400                         if (ret)
401                                 printk(KERN_WARNING "Write clean marker to block at 0x%08x failed: %d\n",
402                                        jeb->offset, ret);
403                         else
404                                 printk(KERN_WARNING "Short write to newly-erased block at 0x%08x: Wanted %zd, got %zd\n",
405                                        jeb->offset, sizeof(marker), retlen);
406
407                         goto filebad;
408                 }
409
410                 /* Everything else got zeroed before the erase */
411                 jeb->free_size = c->sector_size;
412                 /* FIXME Special case for cleanmarker in empty block */
413                 jffs2_link_node_ref(c, jeb, jeb->offset | REF_NORMAL, c->cleanmarker_size, NULL);
414         }
415
416         spin_lock(&c->erase_completion_lock);
417         c->erasing_size -= c->sector_size;
418         c->free_size += jeb->free_size;
419         c->used_size += jeb->used_size;
420
421         jffs2_dbg_acct_sanity_check_nolock(c,jeb);
422         jffs2_dbg_acct_paranoia_check_nolock(c, jeb);
423
424         list_add_tail(&jeb->list, &c->free_list);
425         c->nr_erasing_blocks--;
426         c->nr_free_blocks++;
427         spin_unlock(&c->erase_completion_lock);
428         wake_up(&c->erase_wait);
429         return;
430
431 filebad:
432         spin_lock(&c->erase_completion_lock);
433         /* Stick it on a list (any list) so erase_failed can take it
434            right off again.  Silly, but shouldn't happen often. */
435         list_add(&jeb->list, &c->erasing_list);
436         spin_unlock(&c->erase_completion_lock);
437         jffs2_erase_failed(c, jeb, bad_offset);
438         return;
439
440 refile:
441         /* Stick it back on the list from whence it came and come back later */
442         jffs2_erase_pending_trigger(c);
443         spin_lock(&c->erase_completion_lock);
444         list_add(&jeb->list, &c->erase_complete_list);
445         spin_unlock(&c->erase_completion_lock);
446         return;
447 }