fs/jffs2/fs.c

   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/capability.h>
  16 #include <linux/kernel.h>
  17 #include <linux/sched.h>
  18 #include <linux/fs.h>
  19 #include <linux/list.h>
  20 #include <linux/mtd/mtd.h>
  21 #include <linux/pagemap.h>
  22 #include <linux/slab.h>
  23 #include <linux/vmalloc.h>
  24 #include <linux/vfs.h>
  25 #include <linux/crc32.h>
  26 #include "nodelist.h"
  27
  28 static int jffs2_flash_setup(struct jffs2_sb_info *c);
  29
  30 int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
  31 {
  32         struct jffs2_full_dnode *old_metadata, *new_metadata;
  33         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
  34         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
  35         struct jffs2_raw_inode *ri;
  36         union jffs2_device_node dev;
  37         unsigned char *mdata = NULL;
  38         int mdatalen = 0;
  39         unsigned int ivalid;
  40         uint32_t alloclen;
  41         int ret;
  42         int alloc_type = ALLOC_NORMAL;
  43
  44         jffs2_dbg(1, "%s(): ino #%lu\n", __func__, inode->i_ino);
  45
  46         /* Special cases - we don't want more than one data node
  47            for these types on the medium at any time. So setattr
  48            must read the original data associated with the node
  49            (i.e. the device numbers or the target name) and write
  50            it out again with the appropriate data attached */
  51         if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
  52                 /* For these, we don't actually need to read the old node */
  53                 mdatalen = jffs2_encode_dev(&dev, inode->i_rdev);
  54                 mdata = (char *)&dev;
  55                 jffs2_dbg(1, "%s(): Writing %d bytes of kdev_t\n",
  56                           __func__, mdatalen);
  57         } else if (S_ISLNK(inode->i_mode)) {
  58                 mutex_lock(&f->sem);
  59                 mdatalen = f->metadata->size;
  60                 mdata = kmalloc(f->metadata->size, GFP_USER);
  61                 if (!mdata) {
  62                         mutex_unlock(&f->sem);
  63                         return -ENOMEM;
  64                 }
  65                 ret = jffs2_read_dnode(c, f, f->metadata, mdata, 0, mdatalen);
  66                 if (ret) {
  67                         mutex_unlock(&f->sem);
  68                         kfree(mdata);
  69                         return ret;
  70                 }
  71                 mutex_unlock(&f->sem);
  72                 jffs2_dbg(1, "%s(): Writing %d bytes of symlink target\n",
  73                           __func__, mdatalen);
  74         }
  75
  76         ri = jffs2_alloc_raw_inode();
  77         if (!ri) {
  78                 if (S_ISLNK(inode->i_mode))
  79                         kfree(mdata);
  80                 return -ENOMEM;
  81         }
  82
  83         ret = jffs2_reserve_space(c, sizeof(*ri) + mdatalen, &alloclen,
  84                                   ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
  85         if (ret) {
  86                 jffs2_free_raw_inode(ri);
  87                 if (S_ISLNK(inode->i_mode))
  88                          kfree(mdata);
  89                 return ret;
  90         }
  91         mutex_lock(&f->sem);
  92         ivalid = iattr->ia_valid;
  93
  94         ri->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
  95         ri->nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
  96         ri->totlen = cpu_to_je32(sizeof(*ri) + mdatalen);
  97         ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
  98
  99         ri->ino = cpu_to_je32(inode->i_ino);
 100         ri->version = cpu_to_je32(++f->highest_version);
 101
 102         ri->uid = cpu_to_je16((ivalid & ATTR_UID)?
 103                 from_kuid(&init_user_ns, iattr->ia_uid):i_uid_read(inode));
 104         ri->gid = cpu_to_je16((ivalid & ATTR_GID)?
 105                 from_kgid(&init_user_ns, iattr->ia_gid):i_gid_read(inode));
 106
 107         if (ivalid & ATTR_MODE)
 108                 ri->mode = cpu_to_jemode(iattr->ia_mode);
 109         else
 110                 ri->mode = cpu_to_jemode(inode->i_mode);
 111
 112
 113         ri->isize = cpu_to_je32((ivalid & ATTR_SIZE)?iattr->ia_size:inode->i_size);
 114         ri->atime = cpu_to_je32(I_SEC((ivalid & ATTR_ATIME)?iattr->ia_atime:inode->i_atime));
 115         ri->mtime = cpu_to_je32(I_SEC((ivalid & ATTR_MTIME)?iattr->ia_mtime:inode->i_mtime));
 116         ri->ctime = cpu_to_je32(I_SEC((ivalid & ATTR_CTIME)?iattr->ia_ctime:inode->i_ctime));
 117
 118         ri->offset = cpu_to_je32(0);
 119         ri->csize = ri->dsize = cpu_to_je32(mdatalen);
 120         ri->compr = JFFS2_COMPR_NONE;
 121         if (ivalid & ATTR_SIZE && inode->i_size < iattr->ia_size) {
 122                 /* It's an extension. Make it a hole node */
 123                 ri->compr = JFFS2_COMPR_ZERO;
 124                 ri->dsize = cpu_to_je32(iattr->ia_size - inode->i_size);
 125                 ri->offset = cpu_to_je32(inode->i_size);
 126         } else if (ivalid & ATTR_SIZE && !iattr->ia_size) {
 127                 /* For truncate-to-zero, treat it as deletion because
 128                    it'll always be obsoleting all previous nodes */
 129                 alloc_type = ALLOC_DELETION;
 130         }
 131         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 132         if (mdatalen)
 133                 ri->data_crc = cpu_to_je32(crc32(0, mdata, mdatalen));
 134         else
 135                 ri->data_crc = cpu_to_je32(0);
 136
 137         new_metadata = jffs2_write_dnode(c, f, ri, mdata, mdatalen, alloc_type);
 138         if (S_ISLNK(inode->i_mode))
 139                 kfree(mdata);
 140
 141         if (IS_ERR(new_metadata)) {
 142                 jffs2_complete_reservation(c);
 143                 jffs2_free_raw_inode(ri);
 144                 mutex_unlock(&f->sem);
 145                 return PTR_ERR(new_metadata);
 146         }
 147         /* It worked. Update the inode */
 148         inode->i_atime = ITIME(je32_to_cpu(ri->atime));
 149         inode->i_ctime = ITIME(je32_to_cpu(ri->ctime));
 150         inode->i_mtime = ITIME(je32_to_cpu(ri->mtime));
 151         inode->i_mode = jemode_to_cpu(ri->mode);
 152         i_uid_write(inode, je16_to_cpu(ri->uid));
 153         i_gid_write(inode, je16_to_cpu(ri->gid));
 154
 155
 156         old_metadata = f->metadata;
 157
 158         if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size)
 159                 jffs2_truncate_fragtree (c, &f->fragtree, iattr->ia_size);
 160
 161         if (ivalid & ATTR_SIZE && inode->i_size < iattr->ia_size) {
 162                 jffs2_add_full_dnode_to_inode(c, f, new_metadata);
 163                 inode->i_size = iattr->ia_size;
 164                 inode->i_blocks = (inode->i_size + 511) >> 9;
 165                 f->metadata = NULL;
 166         } else {
 167                 f->metadata = new_metadata;
 168         }
 169         if (old_metadata) {
 170                 jffs2_mark_node_obsolete(c, old_metadata->raw);
 171                 jffs2_free_full_dnode(old_metadata);
 172         }
 173         jffs2_free_raw_inode(ri);
 174
 175         mutex_unlock(&f->sem);
 176         jffs2_complete_reservation(c);
 177
 178         /* We have to do the truncate_setsize() without f->sem held, since
 179            some pages may be locked and waiting for it in readpage().
 180            We are protected from a simultaneous write() extending i_size
 181            back past iattr->ia_size, because do_truncate() holds the
 182            generic inode semaphore. */
 183         if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size) {
 184                 truncate_setsize(inode, iattr->ia_size);
 185                 inode->i_blocks = (inode->i_size + 511) >> 9;
 186         }
 187
 188         return 0;
 189 }
 190
 191 int jffs2_setattr(struct dentry *dentry, struct iattr *iattr)
 192 {
 193         int rc;
 194
 195         rc = inode_change_ok(dentry->d_inode, iattr);
 196         if (rc)
 197                 return rc;
 198
 199         rc = jffs2_do_setattr(dentry->d_inode, iattr);
 200         if (!rc && (iattr->ia_valid & ATTR_MODE))
 201                 rc = jffs2_acl_chmod(dentry->d_inode);
 202
 203         return rc;
 204 }
 205
 206 int jffs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 207 {
 208         struct jffs2_sb_info *c = JFFS2_SB_INFO(dentry->d_sb);
 209         unsigned long avail;
 210
 211         buf->f_type = JFFS2_SUPER_MAGIC;
 212         buf->f_bsize = 1 << PAGE_SHIFT;
 213         buf->f_blocks = c->flash_size >> PAGE_SHIFT;
 214         buf->f_files = 0;
 215         buf->f_ffree = 0;
 216         buf->f_namelen = JFFS2_MAX_NAME_LEN;
 217         buf->f_fsid.val[0] = JFFS2_SUPER_MAGIC;
 218         buf->f_fsid.val[1] = c->mtd->index;
 219
 220         spin_lock(&c->erase_completion_lock);
 221         avail = c->dirty_size + c->free_size;
 222         if (avail > c->sector_size * c->resv_blocks_write)
 223                 avail -= c->sector_size * c->resv_blocks_write;
 224         else
 225                 avail = 0;
 226         spin_unlock(&c->erase_completion_lock);
 227
 228         buf->f_bavail = buf->f_bfree = avail >> PAGE_SHIFT;
 229
 230         return 0;
 231 }
 232
 233
 234 void jffs2_evict_inode (struct inode *inode)
 235 {
 236         /* We can forget about this inode for now - drop all
 237          *  the nodelists associated with it, etc.
 238          */
 239         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 240         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
 241
 242         jffs2_dbg(1, "%s(): ino #%lu mode %o\n",
 243                   __func__, inode->i_ino, inode->i_mode);
 244         truncate_inode_pages(&inode->i_data, 0);
 245         clear_inode(inode);
 246         jffs2_do_clear_inode(c, f);
 247 }
 248
 249 struct inode *jffs2_iget(struct super_block *sb, unsigned long ino)
 250 {
 251         struct jffs2_inode_info *f;
 252         struct jffs2_sb_info *c;
 253         struct jffs2_raw_inode latest_node;
 254         union jffs2_device_node jdev;
 255         struct inode *inode;
 256         dev_t rdev = 0;
 257         int ret;
 258
 259         jffs2_dbg(1, "%s(): ino == %lu\n", __func__, ino);
 260
 261         inode = iget_locked(sb, ino);
 262         if (!inode)
 263                 return ERR_PTR(-ENOMEM);
 264         if (!(inode->i_state & I_NEW))
 265                 return inode;
 266
 267         f = JFFS2_INODE_INFO(inode);
 268         c = JFFS2_SB_INFO(inode->i_sb);
 269
 270         jffs2_init_inode_info(f);
 271         mutex_lock(&f->sem);
 272
 273         ret = jffs2_do_read_inode(c, f, inode->i_ino, &latest_node);
 274
 275         if (ret) {
 276                 mutex_unlock(&f->sem);
 277                 iget_failed(inode);
 278                 return ERR_PTR(ret);
 279         }
 280         inode->i_mode = jemode_to_cpu(latest_node.mode);
 281         i_uid_write(inode, je16_to_cpu(latest_node.uid));
 282         i_gid_write(inode, je16_to_cpu(latest_node.gid));
 283         inode->i_size = je32_to_cpu(latest_node.isize);
 284         inode->i_atime = ITIME(je32_to_cpu(latest_node.atime));
 285         inode->i_mtime = ITIME(je32_to_cpu(latest_node.mtime));
 286         inode->i_ctime = ITIME(je32_to_cpu(latest_node.ctime));
 287
 288         set_nlink(inode, f->inocache->pino_nlink);
 289
 290         inode->i_blocks = (inode->i_size + 511) >> 9;
 291
 292         switch (inode->i_mode & S_IFMT) {
 293
 294         case S_IFLNK:
 295                 inode->i_op = &jffs2_symlink_inode_operations;
 296                 break;
 297
 298         case S_IFDIR:
 299         {
 300                 struct jffs2_full_dirent *fd;
 301                 set_nlink(inode, 2); /* parent and '.' */
 302
 303                 for (fd=f->dents; fd; fd = fd->next) {
 304                         if (fd->type == DT_DIR && fd->ino)
 305                                 inc_nlink(inode);
 306                 }
 307                 /* Root dir gets i_nlink 3 for some reason */
 308                 if (inode->i_ino == 1)
 309                         inc_nlink(inode);
 310
 311                 inode->i_op = &jffs2_dir_inode_operations;
 312                 inode->i_fop = &jffs2_dir_operations;
 313                 break;
 314         }
 315         case S_IFREG:
 316                 inode->i_op = &jffs2_file_inode_operations;
 317                 inode->i_fop = &jffs2_file_operations;
 318                 inode->i_mapping->a_ops = &jffs2_file_address_operations;
 319                 inode->i_mapping->nrpages = 0;
 320                 break;
 321
 322         case S_IFBLK:
 323         case S_IFCHR:
 324                 /* Read the device numbers from the media */
 325                 if (f->metadata->size != sizeof(jdev.old_id) &&
 326                     f->metadata->size != sizeof(jdev.new_id)) {
 327                         pr_notice("Device node has strange size %d\n",
 328                                   f->metadata->size);
 329                         goto error_io;
 330                 }
 331                 jffs2_dbg(1, "Reading device numbers from flash\n");
 332                 ret = jffs2_read_dnode(c, f, f->metadata, (char *)&jdev, 0, f->metadata->size);
 333                 if (ret < 0) {
 334                         /* Eep */
 335                         pr_notice("Read device numbers for inode %lu failed\n",
 336                                   (unsigned long)inode->i_ino);
 337                         goto error;
 338                 }
 339                 if (f->metadata->size == sizeof(jdev.old_id))
 340                         rdev = old_decode_dev(je16_to_cpu(jdev.old_id));
 341                 else
 342                         rdev = new_decode_dev(je32_to_cpu(jdev.new_id));
 343
 344         case S_IFSOCK:
 345         case S_IFIFO:
 346                 inode->i_op = &jffs2_file_inode_operations;
 347                 init_special_inode(inode, inode->i_mode, rdev);
 348                 break;
 349
 350         default:
 351                 pr_warn("%s(): Bogus i_mode %o for ino %lu\n",
 352                         __func__, inode->i_mode, (unsigned long)inode->i_ino);
 353         }
 354
 355         mutex_unlock(&f->sem);
 356
 357         jffs2_dbg(1, "jffs2_read_inode() returning\n");
 358         unlock_new_inode(inode);
 359         return inode;
 360
 361 error_io:
 362         ret = -EIO;
 363 error:
 364         mutex_unlock(&f->sem);
 365         jffs2_do_clear_inode(c, f);
 366         iget_failed(inode);
 367         return ERR_PTR(ret);
 368 }
 369
 370 void jffs2_dirty_inode(struct inode *inode, int flags)
 371 {
 372         struct iattr iattr;
 373
 374         if (!(inode->i_state & I_DIRTY_DATASYNC)) {
 375                 jffs2_dbg(2, "%s(): not calling setattr() for ino #%lu\n",
 376                           __func__, inode->i_ino);
 377                 return;
 378         }
 379
 380         jffs2_dbg(1, "%s(): calling setattr() for ino #%lu\n",
 381                   __func__, inode->i_ino);
 382
 383         iattr.ia_valid = ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_MTIME|ATTR_CTIME;
 384         iattr.ia_mode = inode->i_mode;
 385         iattr.ia_uid = inode->i_uid;
 386         iattr.ia_gid = inode->i_gid;
 387         iattr.ia_atime = inode->i_atime;
 388         iattr.ia_mtime = inode->i_mtime;
 389         iattr.ia_ctime = inode->i_ctime;
 390
 391         jffs2_do_setattr(inode, &iattr);
 392 }
 393
 394 int jffs2_do_remount_fs(struct super_block *sb, int *flags, char *data)
 395 {
 396         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
 397
 398         if (c->flags & JFFS2_SB_FLAG_RO && !(sb->s_flags & MS_RDONLY))
 399                 return -EROFS;
 400
 401         /* We stop if it was running, then restart if it needs to.
 402            This also catches the case where it was stopped and this
 403            is just a remount to restart it.
 404            Flush the writebuffer, if neccecary, else we loose it */
 405         if (!(sb->s_flags & MS_RDONLY)) {
 406                 jffs2_stop_garbage_collect_thread(c);
 407                 mutex_lock(&c->alloc_sem);
 408                 jffs2_flush_wbuf_pad(c);
 409                 mutex_unlock(&c->alloc_sem);
 410         }
 411
 412         if (!(*flags & MS_RDONLY))
 413                 jffs2_start_garbage_collect_thread(c);
 414
 415         *flags |= MS_NOATIME;
 416         return 0;
 417 }
 418
 419 /* jffs2_new_inode: allocate a new inode and inocache, add it to the hash,
 420    fill in the raw_inode while you're at it. */
 421 struct inode *jffs2_new_inode (struct inode *dir_i, umode_t mode, struct jffs2_raw_inode *ri)
 422 {
 423         struct inode *inode;
 424         struct super_block *sb = dir_i->i_sb;
 425         struct jffs2_sb_info *c;
 426         struct jffs2_inode_info *f;
 427         int ret;
 428
 429         jffs2_dbg(1, "%s(): dir_i %ld, mode 0x%x\n",
 430                   __func__, dir_i->i_ino, mode);
 431
 432         c = JFFS2_SB_INFO(sb);
 433
 434         inode = new_inode(sb);
 435
 436         if (!inode)
 437                 return ERR_PTR(-ENOMEM);
 438
 439         f = JFFS2_INODE_INFO(inode);
 440         jffs2_init_inode_info(f);
 441         mutex_lock(&f->sem);
 442
 443         memset(ri, 0, sizeof(*ri));
 444         /* Set OS-specific defaults for new inodes */
 445         ri->uid = cpu_to_je16(from_kuid(&init_user_ns, current_fsuid()));
 446
 447         if (dir_i->i_mode & S_ISGID) {
 448                 ri->gid = cpu_to_je16(i_gid_read(dir_i));
 449                 if (S_ISDIR(mode))
 450                         mode |= S_ISGID;
 451         } else {
 452                 ri->gid = cpu_to_je16(from_kgid(&init_user_ns, current_fsgid()));
 453         }
 454
 455         /* POSIX ACLs have to be processed now, at least partly.
 456            The umask is only applied if there's no default ACL */
 457         ret = jffs2_init_acl_pre(dir_i, inode, &mode);
 458         if (ret) {
 459             make_bad_inode(inode);
 460             iput(inode);
 461             return ERR_PTR(ret);
 462         }
 463         ret = jffs2_do_new_inode (c, f, mode, ri);
 464         if (ret) {
 465                 make_bad_inode(inode);
 466                 iput(inode);
 467                 return ERR_PTR(ret);
 468         }
 469         set_nlink(inode, 1);
 470         inode->i_ino = je32_to_cpu(ri->ino);
 471         inode->i_mode = jemode_to_cpu(ri->mode);
 472         i_gid_write(inode, je16_to_cpu(ri->gid));
 473         i_uid_write(inode, je16_to_cpu(ri->uid));
 474         inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
 475         ri->atime = ri->mtime = ri->ctime = cpu_to_je32(I_SEC(inode->i_mtime));
 476
 477         inode->i_blocks = 0;
 478         inode->i_size = 0;
 479
 480         if (insert_inode_locked(inode) < 0) {
 481                 make_bad_inode(inode);
 482                 iput(inode);
 483                 return ERR_PTR(-EINVAL);
 484         }
 485
 486         return inode;
 487 }
 488
 489 static int calculate_inocache_hashsize(uint32_t flash_size)
 490 {
 491         /*
 492          * Pick a inocache hash size based on the size of the medium.
 493          * Count how many megabytes we're dealing with, apply a hashsize twice
 494          * that size, but rounding down to the usual big powers of 2. And keep
 495          * to sensible bounds.
 496          */
 497
 498         int size_mb = flash_size / 1024 / 1024;
 499         int hashsize = (size_mb * 2) & ~0x3f;
 500
 501         if (hashsize < INOCACHE_HASHSIZE_MIN)
 502                 return INOCACHE_HASHSIZE_MIN;
 503         if (hashsize > INOCACHE_HASHSIZE_MAX)
 504                 return INOCACHE_HASHSIZE_MAX;
 505
 506         return hashsize;
 507 }
 508
 509 int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
 510 {
 511         struct jffs2_sb_info *c;
 512         struct inode *root_i;
 513         int ret;
 514         size_t blocks;
 515
 516         c = JFFS2_SB_INFO(sb);
 517
 518 #ifndef CONFIG_JFFS2_FS_WRITEBUFFER
 519         if (c->mtd->type == MTD_NANDFLASH) {
 520                 pr_err("Cannot operate on NAND flash unless jffs2 NAND support is compiled in\n");
 521                 return -EINVAL;
 522         }
 523         if (c->mtd->type == MTD_DATAFLASH) {
 524                 pr_err("Cannot operate on DataFlash unless jffs2 DataFlash support is compiled in\n");
 525                 return -EINVAL;
 526         }
 527 #endif
 528
 529         c->flash_size = c->mtd->size;
 530         c->sector_size = c->mtd->erasesize;
 531         blocks = c->flash_size / c->sector_size;
 532
 533         /*
 534          * Size alignment check
 535          */
 536         if ((c->sector_size * blocks) != c->flash_size) {
 537                 c->flash_size = c->sector_size * blocks;
 538                 pr_info("Flash size not aligned to erasesize, reducing to %dKiB\n",
 539                         c->flash_size / 1024);
 540         }
 541
 542         if (c->flash_size < 5*c->sector_size) {
 543                 pr_err("Too few erase blocks (%d)\n",
 544                        c->flash_size / c->sector_size);
 545                 return -EINVAL;
 546         }
 547
 548         c->cleanmarker_size = sizeof(struct jffs2_unknown_node);
 549
 550         /* NAND (or other bizarre) flash... do setup accordingly */
 551         ret = jffs2_flash_setup(c);
 552         if (ret)
 553                 return ret;
 554
 555         c->inocache_hashsize = calculate_inocache_hashsize(c->flash_size);
 556         c->inocache_list = kcalloc(c->inocache_hashsize, sizeof(struct jffs2_inode_cache *), GFP_KERNEL);
 557         if (!c->inocache_list) {
 558                 ret = -ENOMEM;
 559                 goto out_wbuf;
 560         }
 561
 562         jffs2_init_xattr_subsystem(c);
 563
 564         if ((ret = jffs2_do_mount_fs(c)))
 565                 goto out_inohash;
 566
 567         jffs2_dbg(1, "%s(): Getting root inode\n", __func__);
 568         root_i = jffs2_iget(sb, 1);
 569         if (IS_ERR(root_i)) {
 570                 jffs2_dbg(1, "get root inode failed\n");
 571                 ret = PTR_ERR(root_i);
 572                 goto out_root;
 573         }
 574
 575         ret = -ENOMEM;
 576
 577         jffs2_dbg(1, "%s(): d_make_root()\n", __func__);
 578         sb->s_root = d_make_root(root_i);
 579         if (!sb->s_root)
 580                 goto out_root;
 581
 582         sb->s_maxbytes = 0xFFFFFFFF;
 583         sb->s_blocksize = PAGE_CACHE_SIZE;
 584         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
 585         sb->s_magic = JFFS2_SUPER_MAGIC;
 586         if (!(sb->s_flags & MS_RDONLY))
 587                 jffs2_start_garbage_collect_thread(c);
 588         return 0;
 589
 590 out_root:
 591         jffs2_free_ino_caches(c);
 592         jffs2_free_raw_node_refs(c);
 593         if (jffs2_blocks_use_vmalloc(c))
 594                 vfree(c->blocks);
 595         else
 596                 kfree(c->blocks);
 597  out_inohash:
 598         jffs2_clear_xattr_subsystem(c);
 599         kfree(c->inocache_list);
 600  out_wbuf:
 601         jffs2_flash_cleanup(c);
 602
 603         return ret;
 604 }
 605
 606 void jffs2_gc_release_inode(struct jffs2_sb_info *c,
 607                                    struct jffs2_inode_info *f)
 608 {
 609         iput(OFNI_EDONI_2SFFJ(f));
 610 }
 611
 612 struct jffs2_inode_info *jffs2_gc_fetch_inode(struct jffs2_sb_info *c,
 613                                               int inum, int unlinked)
 614 {
 615         struct inode *inode;
 616         struct jffs2_inode_cache *ic;
 617
 618         if (unlinked) {
 619                 /* The inode has zero nlink but its nodes weren't yet marked
 620                    obsolete. This has to be because we're still waiting for
 621                    the final (close() and) iput() to happen.
 622
 623                    There's a possibility that the final iput() could have
 624                    happened while we were contemplating. In order to ensure
 625                    that we don't cause a new read_inode() (which would fail)
 626                    for the inode in question, we use ilookup() in this case
 627                    instead of iget().
 628
 629                    The nlink can't _become_ zero at this point because we're
 630                    holding the alloc_sem, and jffs2_do_unlink() would also
 631                    need that while decrementing nlink on any inode.
 632                 */
 633                 inode = ilookup(OFNI_BS_2SFFJ(c), inum);
 634                 if (!inode) {
 635                         jffs2_dbg(1, "ilookup() failed for ino #%u; inode is probably deleted.\n",
 636                                   inum);
 637
 638                         spin_lock(&c->inocache_lock);
 639                         ic = jffs2_get_ino_cache(c, inum);
 640                         if (!ic) {
 641                                 jffs2_dbg(1, "Inode cache for ino #%u is gone\n",
 642                                           inum);
 643                                 spin_unlock(&c->inocache_lock);
 644                                 return NULL;
 645                         }
 646                         if (ic->state != INO_STATE_CHECKEDABSENT) {
 647                                 /* Wait for progress. Don't just loop */
 648                                 jffs2_dbg(1, "Waiting for ino #%u in state %d\n",
 649                                           ic->ino, ic->state);
 650                                 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
 651                         } else {
 652                                 spin_unlock(&c->inocache_lock);
 653                         }
 654
 655                         return NULL;
 656                 }
 657         } else {
 658                 /* Inode has links to it still; they're not going away because
 659                    jffs2_do_unlink() would need the alloc_sem and we have it.
 660                    Just iget() it, and if read_inode() is necessary that's OK.
 661                 */
 662                 inode = jffs2_iget(OFNI_BS_2SFFJ(c), inum);
 663                 if (IS_ERR(inode))
 664                         return ERR_CAST(inode);
 665         }
 666         if (is_bad_inode(inode)) {
 667                 pr_notice("Eep. read_inode() failed for ino #%u. unlinked %d\n",
 668                           inum, unlinked);
 669                 /* NB. This will happen again. We need to do something appropriate here. */
 670                 iput(inode);
 671                 return ERR_PTR(-EIO);
 672         }
 673
 674         return JFFS2_INODE_INFO(inode);
 675 }
 676
 677 unsigned char *jffs2_gc_fetch_page(struct jffs2_sb_info *c,
 678                                    struct jffs2_inode_info *f,
 679                                    unsigned long offset,
 680                                    unsigned long *priv)
 681 {
 682         struct inode *inode = OFNI_EDONI_2SFFJ(f);
 683         struct page *pg;
 684
 685         pg = read_cache_page_async(inode->i_mapping, offset >> PAGE_CACHE_SHIFT,
 686                              (void *)jffs2_do_readpage_unlock, inode);
 687         if (IS_ERR(pg))
 688                 return (void *)pg;
 689
 690         *priv = (unsigned long)pg;
 691         return kmap(pg);
 692 }
 693
 694 void jffs2_gc_release_page(struct jffs2_sb_info *c,
 695                            unsigned char *ptr,
 696                            unsigned long *priv)
 697 {
 698         struct page *pg = (void *)*priv;
 699
 700         kunmap(pg);
 701         page_cache_release(pg);
 702 }
 703
 704 static int jffs2_flash_setup(struct jffs2_sb_info *c) {
 705         int ret = 0;
 706
 707         if (jffs2_cleanmarker_oob(c)) {
 708                 /* NAND flash... do setup accordingly */
 709                 ret = jffs2_nand_flash_setup(c);
 710                 if (ret)
 711                         return ret;
 712         }
 713
 714         /* and Dataflash */
 715         if (jffs2_dataflash(c)) {
 716                 ret = jffs2_dataflash_setup(c);
 717                 if (ret)
 718                         return ret;
 719         }
 720
 721         /* and Intel "Sibley" flash */
 722         if (jffs2_nor_wbuf_flash(c)) {
 723                 ret = jffs2_nor_wbuf_flash_setup(c);
 724                 if (ret)
 725                         return ret;
 726         }
 727
 728         /* and an UBI volume */
 729         if (jffs2_ubivol(c)) {
 730                 ret = jffs2_ubivol_setup(c);
 731                 if (ret)
 732                         return ret;
 733         }
 734
 735         return ret;
 736 }
 737
 738 void jffs2_flash_cleanup(struct jffs2_sb_info *c) {
 739
 740         if (jffs2_cleanmarker_oob(c)) {
 741                 jffs2_nand_flash_cleanup(c);
 742         }
 743
 744         /* and DataFlash */
 745         if (jffs2_dataflash(c)) {
 746                 jffs2_dataflash_cleanup(c);
 747         }
 748
 749         /* and Intel "Sibley" flash */
 750         if (jffs2_nor_wbuf_flash(c)) {
 751                 jffs2_nor_wbuf_flash_cleanup(c);
 752         }
 753
 754         /* and an UBI volume */
 755         if (jffs2_ubivol(c)) {
 756                 jffs2_ubivol_cleanup(c);
 757         }
 758 }