root/fs/jffs2/erase.c

DEFINITIONS

1. jffs2_erase_block
2. jffs2_erase_pending_blocks
3. jffs2_erase_succeeded
4. jffs2_erase_failed
5. jffs2_remove_node_refs_from_ino_list
6. jffs2_free_jeb_node_refs
7. jffs2_block_check_erase
8. jffs2_mark_erased_block

   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 
  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 
 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 
 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 
 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? */
 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 
 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 
 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 
 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 }