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         struct inode *inode = dentry->d_inode;
 194         int rc;
 195
 196         rc = inode_change_ok(inode, iattr);
 197         if (rc)
 198                 return rc;
 199
 200         rc = jffs2_do_setattr(inode, iattr);
 201         if (!rc && (iattr->ia_valid & ATTR_MODE))
 202                 rc = posix_acl_chmod(inode, inode->i_mode);
 203
 204         return rc;
 205 }
 206
 207 int jffs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 208 {
 209         struct jffs2_sb_info *c = JFFS2_SB_INFO(dentry->d_sb);
 210         unsigned long avail;
 211
 212         buf->f_type = JFFS2_SUPER_MAGIC;
 213         buf->f_bsize = 1 << PAGE_SHIFT;
 214         buf->f_blocks = c->flash_size >> PAGE_SHIFT;
 215         buf->f_files = 0;
 216         buf->f_ffree = 0;
 217         buf->f_namelen = JFFS2_MAX_NAME_LEN;
 218         buf->f_fsid.val[0] = JFFS2_SUPER_MAGIC;
 219         buf->f_fsid.val[1] = c->mtd->index;
 220
 221         spin_lock(&c->erase_completion_lock);
 222         avail = c->dirty_size + c->free_size;
 223         if (avail > c->sector_size * c->resv_blocks_write)
 224                 avail -= c->sector_size * c->resv_blocks_write;
 225         else
 226                 avail = 0;
 227         spin_unlock(&c->erase_completion_lock);
 228
 229         buf->f_bavail = buf->f_bfree = avail >> PAGE_SHIFT;
 230
 231         return 0;
 232 }
 233
 234
 235 void jffs2_evict_inode (struct inode *inode)
 236 {
 237         /* We can forget about this inode for now - drop all
 238          *  the nodelists associated with it, etc.
 239          */
 240         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 241         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
 242
 243         jffs2_dbg(1, "%s(): ino #%lu mode %o\n",
 244                   __func__, inode->i_ino, inode->i_mode);
 245         truncate_inode_pages(&inode->i_data, 0);
 246         clear_inode(inode);
 247         jffs2_do_clear_inode(c, f);
 248 }
 249
 250 struct inode *jffs2_iget(struct super_block *sb, unsigned long ino)
 251 {
 252         struct jffs2_inode_info *f;
 253         struct jffs2_sb_info *c;
 254         struct jffs2_raw_inode latest_node;
 255         union jffs2_device_node jdev;
 256         struct inode *inode;
 257         dev_t rdev = 0;
 258         int ret;
 259
 260         jffs2_dbg(1, "%s(): ino == %lu\n", __func__, ino);
 261
 262         inode = iget_locked(sb, ino);
 263         if (!inode)
 264                 return ERR_PTR(-ENOMEM);
 265         if (!(inode->i_state & I_NEW))
 266                 return inode;
 267
 268         f = JFFS2_INODE_INFO(inode);
 269         c = JFFS2_SB_INFO(inode->i_sb);
 270
 271         jffs2_init_inode_info(f);
 272         mutex_lock(&f->sem);
 273
 274         ret = jffs2_do_read_inode(c, f, inode->i_ino, &latest_node);
 275
 276         if (ret) {
 277                 mutex_unlock(&f->sem);
 278                 iget_failed(inode);
 279                 return ERR_PTR(ret);
 280         }
 281         inode->i_mode = jemode_to_cpu(latest_node.mode);
 282         i_uid_write(inode, je16_to_cpu(latest_node.uid));
 283         i_gid_write(inode, je16_to_cpu(latest_node.gid));
 284         inode->i_size = je32_to_cpu(latest_node.isize);
 285         inode->i_atime = ITIME(je32_to_cpu(latest_node.atime));
 286         inode->i_mtime = ITIME(je32_to_cpu(latest_node.mtime));
 287         inode->i_ctime = ITIME(je32_to_cpu(latest_node.ctime));
 288
 289         set_nlink(inode, f->inocache->pino_nlink);
 290
 291         inode->i_blocks = (inode->i_size + 511) >> 9;
 292
 293         switch (inode->i_mode & S_IFMT) {
 294
 295         case S_IFLNK:
 296                 inode->i_op = &jffs2_symlink_inode_operations;
 297                 break;
 298
 299         case S_IFDIR:
 300         {
 301                 struct jffs2_full_dirent *fd;
 302                 set_nlink(inode, 2); /* parent and '.' */
 303
 304                 for (fd=f->dents; fd; fd = fd->next) {
 305                         if (fd->type == DT_DIR && fd->ino)
 306                                 inc_nlink(inode);
 307                 }
 308                 /* Root dir gets i_nlink 3 for some reason */
 309                 if (inode->i_ino == 1)
 310                         inc_nlink(inode);
 311
 312                 inode->i_op = &jffs2_dir_inode_operations;
 313                 inode->i_fop = &jffs2_dir_operations;
 314                 break;
 315         }
 316         case S_IFREG:
 317                 inode->i_op = &jffs2_file_inode_operations;
 318                 inode->i_fop = &jffs2_file_operations;
 319                 inode->i_mapping->a_ops = &jffs2_file_address_operations;
 320                 inode->i_mapping->nrpages = 0;
 321                 break;
 322
 323         case S_IFBLK:
 324         case S_IFCHR:
 325                 /* Read the device numbers from the media */
 326                 if (f->metadata->size != sizeof(jdev.old_id) &&
 327                     f->metadata->size != sizeof(jdev.new_id)) {
 328                         pr_notice("Device node has strange size %d\n",
 329                                   f->metadata->size);
 330                         goto error_io;
 331                 }
 332                 jffs2_dbg(1, "Reading device numbers from flash\n");
 333                 ret = jffs2_read_dnode(c, f, f->metadata, (char *)&jdev, 0, f->metadata->size);
 334                 if (ret < 0) {
 335                         /* Eep */
 336                         pr_notice("Read device numbers for inode %lu failed\n",
 337                                   (unsigned long)inode->i_ino);
 338                         goto error;
 339                 }
 340                 if (f->metadata->size == sizeof(jdev.old_id))
 341                         rdev = old_decode_dev(je16_to_cpu(jdev.old_id));
 342                 else
 343                         rdev = new_decode_dev(je32_to_cpu(jdev.new_id));
 344
 345         case S_IFSOCK:
 346         case S_IFIFO:
 347                 inode->i_op = &jffs2_file_inode_operations;
 348                 init_special_inode(inode, inode->i_mode, rdev);
 349                 break;
 350
 351         default:
 352                 pr_warn("%s(): Bogus i_mode %o for ino %lu\n",
 353                         __func__, inode->i_mode, (unsigned long)inode->i_ino);
 354         }
 355
 356         mutex_unlock(&f->sem);
 357
 358         jffs2_dbg(1, "jffs2_read_inode() returning\n");
 359         unlock_new_inode(inode);
 360         return inode;
 361
 362 error_io:
 363         ret = -EIO;
 364 error:
 365         mutex_unlock(&f->sem);
 366         jffs2_do_clear_inode(c, f);
 367         iget_failed(inode);
 368         return ERR_PTR(ret);
 369 }
 370
 371 void jffs2_dirty_inode(struct inode *inode, int flags)
 372 {
 373         struct iattr iattr;
 374
 375         if (!(inode->i_state & I_DIRTY_DATASYNC)) {
 376                 jffs2_dbg(2, "%s(): not calling setattr() for ino #%lu\n",
 377                           __func__, inode->i_ino);
 378                 return;
 379         }
 380
 381         jffs2_dbg(1, "%s(): calling setattr() for ino #%lu\n",
 382                   __func__, inode->i_ino);
 383
 384         iattr.ia_valid = ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_MTIME|ATTR_CTIME;
 385         iattr.ia_mode = inode->i_mode;
 386         iattr.ia_uid = inode->i_uid;
 387         iattr.ia_gid = inode->i_gid;
 388         iattr.ia_atime = inode->i_atime;
 389         iattr.ia_mtime = inode->i_mtime;
 390         iattr.ia_ctime = inode->i_ctime;
 391
 392         jffs2_do_setattr(inode, &iattr);
 393 }
 394
 395 int jffs2_do_remount_fs(struct super_block *sb, int *flags, char *data)
 396 {
 397         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
 398
 399         if (c->flags & JFFS2_SB_FLAG_RO && !(sb->s_flags & MS_RDONLY))
 400                 return -EROFS;
 401
 402         /* We stop if it was running, then restart if it needs to.
 403            This also catches the case where it was stopped and this
 404            is just a remount to restart it.
 405            Flush the writebuffer, if neccecary, else we loose it */
 406         if (!(sb->s_flags & MS_RDONLY)) {
 407                 jffs2_stop_garbage_collect_thread(c);
 408                 mutex_lock(&c->alloc_sem);
 409                 jffs2_flush_wbuf_pad(c);
 410                 mutex_unlock(&c->alloc_sem);
 411         }
 412
 413         if (!(*flags & MS_RDONLY))
 414                 jffs2_start_garbage_collect_thread(c);
 415
 416         *flags |= MS_NOATIME;
 417         return 0;
 418 }
 419
 420 /* jffs2_new_inode: allocate a new inode and inocache, add it to the hash,
 421    fill in the raw_inode while you're at it. */
 422 struct inode *jffs2_new_inode (struct inode *dir_i, umode_t mode, struct jffs2_raw_inode *ri)
 423 {
 424         struct inode *inode;
 425         struct super_block *sb = dir_i->i_sb;
 426         struct jffs2_sb_info *c;
 427         struct jffs2_inode_info *f;
 428         int ret;
 429
 430         jffs2_dbg(1, "%s(): dir_i %ld, mode 0x%x\n",
 431                   __func__, dir_i->i_ino, mode);
 432
 433         c = JFFS2_SB_INFO(sb);
 434
 435         inode = new_inode(sb);
 436
 437         if (!inode)
 438                 return ERR_PTR(-ENOMEM);
 439
 440         f = JFFS2_INODE_INFO(inode);
 441         jffs2_init_inode_info(f);
 442         mutex_lock(&f->sem);
 443
 444         memset(ri, 0, sizeof(*ri));
 445         /* Set OS-specific defaults for new inodes */
 446         ri->uid = cpu_to_je16(from_kuid(&init_user_ns, current_fsuid()));
 447
 448         if (dir_i->i_mode & S_ISGID) {
 449                 ri->gid = cpu_to_je16(i_gid_read(dir_i));
 450                 if (S_ISDIR(mode))
 451                         mode |= S_ISGID;
 452         } else {
 453                 ri->gid = cpu_to_je16(from_kgid(&init_user_ns, current_fsgid()));
 454         }
 455
 456         /* POSIX ACLs have to be processed now, at least partly.
 457            The umask is only applied if there's no default ACL */
 458         ret = jffs2_init_acl_pre(dir_i, inode, &mode);
 459         if (ret) {
 460             make_bad_inode(inode);
 461             iput(inode);
 462             return ERR_PTR(ret);
 463         }
 464         ret = jffs2_do_new_inode (c, f, mode, ri);
 465         if (ret) {
 466                 make_bad_inode(inode);
 467                 iput(inode);
 468                 return ERR_PTR(ret);
 469         }
 470         set_nlink(inode, 1);
 471         inode->i_ino = je32_to_cpu(ri->ino);
 472         inode->i_mode = jemode_to_cpu(ri->mode);
 473         i_gid_write(inode, je16_to_cpu(ri->gid));
 474         i_uid_write(inode, je16_to_cpu(ri->uid));
 475         inode->i_atime = inode->i_ctime = inode->i_mtime = CURRENT_TIME_SEC;
 476         ri->atime = ri->mtime = ri->ctime = cpu_to_je32(I_SEC(inode->i_mtime));
 477
 478         inode->i_blocks = 0;
 479         inode->i_size = 0;
 480
 481         if (insert_inode_locked(inode) < 0) {
 482                 make_bad_inode(inode);
 483                 iput(inode);
 484                 return ERR_PTR(-EINVAL);
 485         }
 486
 487         return inode;
 488 }
 489
 490 static int calculate_inocache_hashsize(uint32_t flash_size)
 491 {
 492         /*
 493          * Pick a inocache hash size based on the size of the medium.
 494          * Count how many megabytes we're dealing with, apply a hashsize twice
 495          * that size, but rounding down to the usual big powers of 2. And keep
 496          * to sensible bounds.
 497          */
 498
 499         int size_mb = flash_size / 1024 / 1024;
 500         int hashsize = (size_mb * 2) & ~0x3f;
 501
 502         if (hashsize < INOCACHE_HASHSIZE_MIN)
 503                 return INOCACHE_HASHSIZE_MIN;
 504         if (hashsize > INOCACHE_HASHSIZE_MAX)
 505                 return INOCACHE_HASHSIZE_MAX;
 506
 507         return hashsize;
 508 }
 509
 510 int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
 511 {
 512         struct jffs2_sb_info *c;
 513         struct inode *root_i;
 514         int ret;
 515         size_t blocks;
 516
 517         c = JFFS2_SB_INFO(sb);
 518
 519         /* Do not support the MLC nand */
 520         if (c->mtd->type == MTD_MLCNANDFLASH)
 521                 return -EINVAL;
 522
 523 #ifndef CONFIG_JFFS2_FS_WRITEBUFFER
 524         if (c->mtd->type == MTD_NANDFLASH) {
 525                 pr_err("Cannot operate on NAND flash unless jffs2 NAND support is compiled in\n");
 526                 return -EINVAL;
 527         }
 528         if (c->mtd->type == MTD_DATAFLASH) {
 529                 pr_err("Cannot operate on DataFlash unless jffs2 DataFlash support is compiled in\n");
 530                 return -EINVAL;
 531         }
 532 #endif
 533
 534         c->flash_size = c->mtd->size;
 535         c->sector_size = c->mtd->erasesize;
 536         blocks = c->flash_size / c->sector_size;
 537
 538         /*
 539          * Size alignment check
 540          */
 541         if ((c->sector_size * blocks) != c->flash_size) {
 542                 c->flash_size = c->sector_size * blocks;
 543                 pr_info("Flash size not aligned to erasesize, reducing to %dKiB\n",
 544                         c->flash_size / 1024);
 545         }
 546
 547         if (c->flash_size < 5*c->sector_size) {
 548                 pr_err("Too few erase blocks (%d)\n",
 549                        c->flash_size / c->sector_size);
 550                 return -EINVAL;
 551         }
 552
 553         c->cleanmarker_size = sizeof(struct jffs2_unknown_node);
 554
 555         /* NAND (or other bizarre) flash... do setup accordingly */
 556         ret = jffs2_flash_setup(c);
 557         if (ret)
 558                 return ret;
 559
 560         c->inocache_hashsize = calculate_inocache_hashsize(c->flash_size);
 561         c->inocache_list = kcalloc(c->inocache_hashsize, sizeof(struct jffs2_inode_cache *), GFP_KERNEL);
 562         if (!c->inocache_list) {
 563                 ret = -ENOMEM;
 564                 goto out_wbuf;
 565         }
 566
 567         jffs2_init_xattr_subsystem(c);
 568
 569         if ((ret = jffs2_do_mount_fs(c)))
 570                 goto out_inohash;
 571
 572         jffs2_dbg(1, "%s(): Getting root inode\n", __func__);
 573         root_i = jffs2_iget(sb, 1);
 574         if (IS_ERR(root_i)) {
 575                 jffs2_dbg(1, "get root inode failed\n");
 576                 ret = PTR_ERR(root_i);
 577                 goto out_root;
 578         }
 579
 580         ret = -ENOMEM;
 581
 582         jffs2_dbg(1, "%s(): d_make_root()\n", __func__);
 583         sb->s_root = d_make_root(root_i);
 584         if (!sb->s_root)
 585                 goto out_root;
 586
 587         sb->s_maxbytes = 0xFFFFFFFF;
 588         sb->s_blocksize = PAGE_CACHE_SIZE;
 589         sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
 590         sb->s_magic = JFFS2_SUPER_MAGIC;
 591         if (!(sb->s_flags & MS_RDONLY))
 592                 jffs2_start_garbage_collect_thread(c);
 593         return 0;
 594
 595 out_root:
 596         jffs2_free_ino_caches(c);
 597         jffs2_free_raw_node_refs(c);
 598         if (jffs2_blocks_use_vmalloc(c))
 599                 vfree(c->blocks);
 600         else
 601                 kfree(c->blocks);
 602  out_inohash:
 603         jffs2_clear_xattr_subsystem(c);
 604         kfree(c->inocache_list);
 605  out_wbuf:
 606         jffs2_flash_cleanup(c);
 607
 608         return ret;
 609 }
 610
 611 void jffs2_gc_release_inode(struct jffs2_sb_info *c,
 612                                    struct jffs2_inode_info *f)
 613 {
 614         iput(OFNI_EDONI_2SFFJ(f));
 615 }
 616
 617 struct jffs2_inode_info *jffs2_gc_fetch_inode(struct jffs2_sb_info *c,
 618                                               int inum, int unlinked)
 619 {
 620         struct inode *inode;
 621         struct jffs2_inode_cache *ic;
 622
 623         if (unlinked) {
 624                 /* The inode has zero nlink but its nodes weren't yet marked
 625                    obsolete. This has to be because we're still waiting for
 626                    the final (close() and) iput() to happen.
 627
 628                    There's a possibility that the final iput() could have
 629                    happened while we were contemplating. In order to ensure
 630                    that we don't cause a new read_inode() (which would fail)
 631                    for the inode in question, we use ilookup() in this case
 632                    instead of iget().
 633
 634                    The nlink can't _become_ zero at this point because we're
 635                    holding the alloc_sem, and jffs2_do_unlink() would also
 636                    need that while decrementing nlink on any inode.
 637                 */
 638                 inode = ilookup(OFNI_BS_2SFFJ(c), inum);
 639                 if (!inode) {
 640                         jffs2_dbg(1, "ilookup() failed for ino #%u; inode is probably deleted.\n",
 641                                   inum);
 642
 643                         spin_lock(&c->inocache_lock);
 644                         ic = jffs2_get_ino_cache(c, inum);
 645                         if (!ic) {
 646                                 jffs2_dbg(1, "Inode cache for ino #%u is gone\n",
 647                                           inum);
 648                                 spin_unlock(&c->inocache_lock);
 649                                 return NULL;
 650                         }
 651                         if (ic->state != INO_STATE_CHECKEDABSENT) {
 652                                 /* Wait for progress. Don't just loop */
 653                                 jffs2_dbg(1, "Waiting for ino #%u in state %d\n",
 654                                           ic->ino, ic->state);
 655                                 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
 656                         } else {
 657                                 spin_unlock(&c->inocache_lock);
 658                         }
 659
 660                         return NULL;
 661                 }
 662         } else {
 663                 /* Inode has links to it still; they're not going away because
 664                    jffs2_do_unlink() would need the alloc_sem and we have it.
 665                    Just iget() it, and if read_inode() is necessary that's OK.
 666                 */
 667                 inode = jffs2_iget(OFNI_BS_2SFFJ(c), inum);
 668                 if (IS_ERR(inode))
 669                         return ERR_CAST(inode);
 670         }
 671         if (is_bad_inode(inode)) {
 672                 pr_notice("Eep. read_inode() failed for ino #%u. unlinked %d\n",
 673                           inum, unlinked);
 674                 /* NB. This will happen again. We need to do something appropriate here. */
 675                 iput(inode);
 676                 return ERR_PTR(-EIO);
 677         }
 678
 679         return JFFS2_INODE_INFO(inode);
 680 }
 681
 682 unsigned char *jffs2_gc_fetch_page(struct jffs2_sb_info *c,
 683                                    struct jffs2_inode_info *f,
 684                                    unsigned long offset,
 685                                    unsigned long *priv)
 686 {
 687         struct inode *inode = OFNI_EDONI_2SFFJ(f);
 688         struct page *pg;
 689
 690         pg = read_cache_page_async(inode->i_mapping, offset >> PAGE_CACHE_SHIFT,
 691                              (void *)jffs2_do_readpage_unlock, inode);
 692         if (IS_ERR(pg))
 693                 return (void *)pg;
 694
 695         *priv = (unsigned long)pg;
 696         return kmap(pg);
 697 }
 698
 699 void jffs2_gc_release_page(struct jffs2_sb_info *c,
 700                            unsigned char *ptr,
 701                            unsigned long *priv)
 702 {
 703         struct page *pg = (void *)*priv;
 704
 705         kunmap(pg);
 706         page_cache_release(pg);
 707 }
 708
 709 static int jffs2_flash_setup(struct jffs2_sb_info *c) {
 710         int ret = 0;
 711
 712         if (jffs2_cleanmarker_oob(c)) {
 713                 /* NAND flash... do setup accordingly */
 714                 ret = jffs2_nand_flash_setup(c);
 715                 if (ret)
 716                         return ret;
 717         }
 718
 719         /* and Dataflash */
 720         if (jffs2_dataflash(c)) {
 721                 ret = jffs2_dataflash_setup(c);
 722                 if (ret)
 723                         return ret;
 724         }
 725
 726         /* and Intel "Sibley" flash */
 727         if (jffs2_nor_wbuf_flash(c)) {
 728                 ret = jffs2_nor_wbuf_flash_setup(c);
 729                 if (ret)
 730                         return ret;
 731         }
 732
 733         /* and an UBI volume */
 734         if (jffs2_ubivol(c)) {
 735                 ret = jffs2_ubivol_setup(c);
 736                 if (ret)
 737                         return ret;
 738         }
 739
 740         return ret;
 741 }
 742
 743 void jffs2_flash_cleanup(struct jffs2_sb_info *c) {
 744
 745         if (jffs2_cleanmarker_oob(c)) {
 746                 jffs2_nand_flash_cleanup(c);
 747         }
 748
 749         /* and DataFlash */
 750         if (jffs2_dataflash(c)) {
 751                 jffs2_dataflash_cleanup(c);
 752         }
 753
 754         /* and Intel "Sibley" flash */
 755         if (jffs2_nor_wbuf_flash(c)) {
 756                 jffs2_nor_wbuf_flash_cleanup(c);
 757         }
 758
 759         /* and an UBI volume */
 760         if (jffs2_ubivol(c)) {
 761                 jffs2_ubivol_cleanup(c);
 762         }
 763 }