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/cred.h>
  19 #include <linux/fs.h>
  20 #include <linux/list.h>
  21 #include <linux/mtd/mtd.h>
  22 #include <linux/pagemap.h>
  23 #include <linux/slab.h>
  24 #include <linux/vmalloc.h>
  25 #include <linux/vfs.h>
  26 #include <linux/crc32.h>
  27 #include "nodelist.h"
  28
  29 static int jffs2_flash_setup(struct jffs2_sb_info *c);
  30
  31 int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
  32 {
  33         struct jffs2_full_dnode *old_metadata, *new_metadata;
  34         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
  35         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
  36         struct jffs2_raw_inode *ri;
  37         union jffs2_device_node dev;
  38         unsigned char *mdata = NULL;
  39         int mdatalen = 0;
  40         unsigned int ivalid;
  41         uint32_t alloclen;
  42         int ret;
  43         int alloc_type = ALLOC_NORMAL;
  44
  45         jffs2_dbg(1, "%s(): ino #%lu\n", __func__, inode->i_ino);
  46
  47         /* Special cases - we don't want more than one data node
  48            for these types on the medium at any time. So setattr
  49            must read the original data associated with the node
  50            (i.e. the device numbers or the target name) and write
  51            it out again with the appropriate data attached */
  52         if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
  53                 /* For these, we don't actually need to read the old node */
  54                 mdatalen = jffs2_encode_dev(&dev, inode->i_rdev);
  55                 mdata = (char *)&dev;
  56                 jffs2_dbg(1, "%s(): Writing %d bytes of kdev_t\n",
  57                           __func__, mdatalen);
  58         } else if (S_ISLNK(inode->i_mode)) {
  59                 mutex_lock(&f->sem);
  60                 mdatalen = f->metadata->size;
  61                 mdata = kmalloc(f->metadata->size, GFP_USER);
  62                 if (!mdata) {
  63                         mutex_unlock(&f->sem);
  64                         return -ENOMEM;
  65                 }
  66                 ret = jffs2_read_dnode(c, f, f->metadata, mdata, 0, mdatalen);
  67                 if (ret) {
  68                         mutex_unlock(&f->sem);
  69                         kfree(mdata);
  70                         return ret;
  71                 }
  72                 mutex_unlock(&f->sem);
  73                 jffs2_dbg(1, "%s(): Writing %d bytes of symlink target\n",
  74                           __func__, mdatalen);
  75         }
  76
  77         ri = jffs2_alloc_raw_inode();
  78         if (!ri) {
  79                 if (S_ISLNK(inode->i_mode))
  80                         kfree(mdata);
  81                 return -ENOMEM;
  82         }
  83
  84         ret = jffs2_reserve_space(c, sizeof(*ri) + mdatalen, &alloclen,
  85                                   ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
  86         if (ret) {
  87                 jffs2_free_raw_inode(ri);
  88                 if (S_ISLNK(inode->i_mode))
  89                          kfree(mdata);
  90                 return ret;
  91         }
  92         mutex_lock(&f->sem);
  93         ivalid = iattr->ia_valid;
  94
  95         ri->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
  96         ri->nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
  97         ri->totlen = cpu_to_je32(sizeof(*ri) + mdatalen);
  98         ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
  99
 100         ri->ino = cpu_to_je32(inode->i_ino);
 101         ri->version = cpu_to_je32(++f->highest_version);
 102
 103         ri->uid = cpu_to_je16((ivalid & ATTR_UID)?
 104                 from_kuid(&init_user_ns, iattr->ia_uid):i_uid_read(inode));
 105         ri->gid = cpu_to_je16((ivalid & ATTR_GID)?
 106                 from_kgid(&init_user_ns, iattr->ia_gid):i_gid_read(inode));
 107
 108         if (ivalid & ATTR_MODE)
 109                 ri->mode = cpu_to_jemode(iattr->ia_mode);
 110         else
 111                 ri->mode = cpu_to_jemode(inode->i_mode);
 112
 113
 114         ri->isize = cpu_to_je32((ivalid & ATTR_SIZE)?iattr->ia_size:inode->i_size);
 115         ri->atime = cpu_to_je32(I_SEC((ivalid & ATTR_ATIME)?iattr->ia_atime:inode->i_atime));
 116         ri->mtime = cpu_to_je32(I_SEC((ivalid & ATTR_MTIME)?iattr->ia_mtime:inode->i_mtime));
 117         ri->ctime = cpu_to_je32(I_SEC((ivalid & ATTR_CTIME)?iattr->ia_ctime:inode->i_ctime));
 118
 119         ri->offset = cpu_to_je32(0);
 120         ri->csize = ri->dsize = cpu_to_je32(mdatalen);
 121         ri->compr = JFFS2_COMPR_NONE;
 122         if (ivalid & ATTR_SIZE && inode->i_size < iattr->ia_size) {
 123                 /* It's an extension. Make it a hole node */
 124                 ri->compr = JFFS2_COMPR_ZERO;
 125                 ri->dsize = cpu_to_je32(iattr->ia_size - inode->i_size);
 126                 ri->offset = cpu_to_je32(inode->i_size);
 127         } else if (ivalid & ATTR_SIZE && !iattr->ia_size) {
 128                 /* For truncate-to-zero, treat it as deletion because
 129                    it'll always be obsoleting all previous nodes */
 130                 alloc_type = ALLOC_DELETION;
 131         }
 132         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 133         if (mdatalen)
 134                 ri->data_crc = cpu_to_je32(crc32(0, mdata, mdatalen));
 135         else
 136                 ri->data_crc = cpu_to_je32(0);
 137
 138         new_metadata = jffs2_write_dnode(c, f, ri, mdata, mdatalen, alloc_type);
 139         if (S_ISLNK(inode->i_mode))
 140                 kfree(mdata);
 141
 142         if (IS_ERR(new_metadata)) {
 143                 jffs2_complete_reservation(c);
 144                 jffs2_free_raw_inode(ri);
 145                 mutex_unlock(&f->sem);
 146                 return PTR_ERR(new_metadata);
 147         }
 148         /* It worked. Update the inode */
 149         inode->i_atime = ITIME(je32_to_cpu(ri->atime));
 150         inode->i_ctime = ITIME(je32_to_cpu(ri->ctime));
 151         inode->i_mtime = ITIME(je32_to_cpu(ri->mtime));
 152         inode->i_mode = jemode_to_cpu(ri->mode);
 153         i_uid_write(inode, je16_to_cpu(ri->uid));
 154         i_gid_write(inode, je16_to_cpu(ri->gid));
 155
 156
 157         old_metadata = f->metadata;
 158
 159         if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size)
 160                 jffs2_truncate_fragtree (c, &f->fragtree, iattr->ia_size);
 161
 162         if (ivalid & ATTR_SIZE && inode->i_size < iattr->ia_size) {
 163                 jffs2_add_full_dnode_to_inode(c, f, new_metadata);
 164                 inode->i_size = iattr->ia_size;
 165                 inode->i_blocks = (inode->i_size + 511) >> 9;
 166                 f->metadata = NULL;
 167         } else {
 168                 f->metadata = new_metadata;
 169         }
 170         if (old_metadata) {
 171                 jffs2_mark_node_obsolete(c, old_metadata->raw);
 172                 jffs2_free_full_dnode(old_metadata);
 173         }
 174         jffs2_free_raw_inode(ri);
 175
 176         mutex_unlock(&f->sem);
 177         jffs2_complete_reservation(c);
 178
 179         /* We have to do the truncate_setsize() without f->sem held, since
 180            some pages may be locked and waiting for it in readpage().
 181            We are protected from a simultaneous write() extending i_size
 182            back past iattr->ia_size, because do_truncate() holds the
 183            generic inode semaphore. */
 184         if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size) {
 185                 truncate_setsize(inode, iattr->ia_size);
 186                 inode->i_blocks = (inode->i_size + 511) >> 9;
 187         }
 188
 189         return 0;
 190 }
 191
 192 int jffs2_setattr(struct dentry *dentry, struct iattr *iattr)
 193 {
 194         struct inode *inode = d_inode(dentry);
 195         int rc;
 196
 197         rc = setattr_prepare(dentry, iattr);
 198         if (rc)
 199                 return rc;
 200
 201         rc = jffs2_do_setattr(inode, iattr);
 202         if (!rc && (iattr->ia_valid & ATTR_MODE))
 203                 rc = posix_acl_chmod(inode, inode->i_mode);
 204
 205         return rc;
 206 }
 207
 208 int jffs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 209 {
 210         struct jffs2_sb_info *c = JFFS2_SB_INFO(dentry->d_sb);
 211         unsigned long avail;
 212
 213         buf->f_type = JFFS2_SUPER_MAGIC;
 214         buf->f_bsize = 1 << PAGE_SHIFT;
 215         buf->f_blocks = c->flash_size >> PAGE_SHIFT;
 216         buf->f_files = 0;
 217         buf->f_ffree = 0;
 218         buf->f_namelen = JFFS2_MAX_NAME_LEN;
 219         buf->f_fsid.val[0] = JFFS2_SUPER_MAGIC;
 220         buf->f_fsid.val[1] = c->mtd->index;
 221
 222         spin_lock(&c->erase_completion_lock);
 223         avail = c->dirty_size + c->free_size;
 224         if (avail > c->sector_size * c->resv_blocks_write)
 225                 avail -= c->sector_size * c->resv_blocks_write;
 226         else
 227                 avail = 0;
 228         spin_unlock(&c->erase_completion_lock);
 229
 230         buf->f_bavail = buf->f_bfree = avail >> PAGE_SHIFT;
 231
 232         return 0;
 233 }
 234
 235
 236 void jffs2_evict_inode (struct inode *inode)
 237 {
 238         /* We can forget about this inode for now - drop all
 239          *  the nodelists associated with it, etc.
 240          */
 241         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 242         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
 243
 244         jffs2_dbg(1, "%s(): ino #%lu mode %o\n",
 245                   __func__, inode->i_ino, inode->i_mode);
 246         truncate_inode_pages_final(&inode->i_data);
 247         clear_inode(inode);
 248         jffs2_do_clear_inode(c, f);
 249 }
 250
 251 struct inode *jffs2_iget(struct super_block *sb, unsigned long ino)
 252 {
 253         struct jffs2_inode_info *f;
 254         struct jffs2_sb_info *c;
 255         struct jffs2_raw_inode latest_node;
 256         union jffs2_device_node jdev;
 257         struct inode *inode;
 258         dev_t rdev = 0;
 259         int ret;
 260
 261         jffs2_dbg(1, "%s(): ino == %lu\n", __func__, ino);
 262
 263         inode = iget_locked(sb, ino);
 264         if (!inode)
 265                 return ERR_PTR(-ENOMEM);
 266         if (!(inode->i_state & I_NEW))
 267                 return inode;
 268
 269         f = JFFS2_INODE_INFO(inode);
 270         c = JFFS2_SB_INFO(inode->i_sb);
 271
 272         jffs2_init_inode_info(f);
 273         mutex_lock(&f->sem);
 274
 275         ret = jffs2_do_read_inode(c, f, inode->i_ino, &latest_node);
 276         if (ret)
 277                 goto error;
 278
 279         inode->i_mode = jemode_to_cpu(latest_node.mode);
 280         i_uid_write(inode, je16_to_cpu(latest_node.uid));
 281         i_gid_write(inode, je16_to_cpu(latest_node.gid));
 282         inode->i_size = je32_to_cpu(latest_node.isize);
 283         inode->i_atime = ITIME(je32_to_cpu(latest_node.atime));
 284         inode->i_mtime = ITIME(je32_to_cpu(latest_node.mtime));
 285         inode->i_ctime = ITIME(je32_to_cpu(latest_node.ctime));
 286
 287         set_nlink(inode, f->inocache->pino_nlink);
 288
 289         inode->i_blocks = (inode->i_size + 511) >> 9;
 290
 291         switch (inode->i_mode & S_IFMT) {
 292
 293         case S_IFLNK:
 294                 inode->i_op = &jffs2_symlink_inode_operations;
 295                 inode->i_link = f->target;
 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         iget_failed(inode);
 366         return ERR_PTR(ret);
 367 }
 368
 369 void jffs2_dirty_inode(struct inode *inode, int flags)
 370 {
 371         struct iattr iattr;
 372
 373         if (!(inode->i_state & I_DIRTY_DATASYNC)) {
 374                 jffs2_dbg(2, "%s(): not calling setattr() for ino #%lu\n",
 375                           __func__, inode->i_ino);
 376                 return;
 377         }
 378
 379         jffs2_dbg(1, "%s(): calling setattr() for ino #%lu\n",
 380                   __func__, inode->i_ino);
 381
 382         iattr.ia_valid = ATTR_MODE|ATTR_UID|ATTR_GID|ATTR_ATIME|ATTR_MTIME|ATTR_CTIME;
 383         iattr.ia_mode = inode->i_mode;
 384         iattr.ia_uid = inode->i_uid;
 385         iattr.ia_gid = inode->i_gid;
 386         iattr.ia_atime = inode->i_atime;
 387         iattr.ia_mtime = inode->i_mtime;
 388         iattr.ia_ctime = inode->i_ctime;
 389
 390         jffs2_do_setattr(inode, &iattr);
 391 }
 392
 393 int jffs2_do_remount_fs(struct super_block *sb, int *flags, char *data)
 394 {
 395         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
 396
 397         if (c->flags & JFFS2_SB_FLAG_RO && !sb_rdonly(sb))
 398                 return -EROFS;
 399
 400         /* We stop if it was running, then restart if it needs to.
 401            This also catches the case where it was stopped and this
 402            is just a remount to restart it.
 403            Flush the writebuffer, if neccecary, else we loose it */
 404         if (!sb_rdonly(sb)) {
 405                 jffs2_stop_garbage_collect_thread(c);
 406                 mutex_lock(&c->alloc_sem);
 407                 jffs2_flush_wbuf_pad(c);
 408                 mutex_unlock(&c->alloc_sem);
 409         }
 410
 411         if (!(*flags & SB_RDONLY))
 412                 jffs2_start_garbage_collect_thread(c);
 413
 414         *flags |= SB_NOATIME;
 415         return 0;
 416 }
 417
 418 /* jffs2_new_inode: allocate a new inode and inocache, add it to the hash,
 419    fill in the raw_inode while you're at it. */
 420 struct inode *jffs2_new_inode (struct inode *dir_i, umode_t mode, struct jffs2_raw_inode *ri)
 421 {
 422         struct inode *inode;
 423         struct super_block *sb = dir_i->i_sb;
 424         struct jffs2_sb_info *c;
 425         struct jffs2_inode_info *f;
 426         int ret;
 427
 428         jffs2_dbg(1, "%s(): dir_i %ld, mode 0x%x\n",
 429                   __func__, dir_i->i_ino, mode);
 430
 431         c = JFFS2_SB_INFO(sb);
 432
 433         inode = new_inode(sb);
 434
 435         if (!inode)
 436                 return ERR_PTR(-ENOMEM);
 437
 438         f = JFFS2_INODE_INFO(inode);
 439         jffs2_init_inode_info(f);
 440         mutex_lock(&f->sem);
 441
 442         memset(ri, 0, sizeof(*ri));
 443         /* Set OS-specific defaults for new inodes */
 444         ri->uid = cpu_to_je16(from_kuid(&init_user_ns, current_fsuid()));
 445
 446         if (dir_i->i_mode & S_ISGID) {
 447                 ri->gid = cpu_to_je16(i_gid_read(dir_i));
 448                 if (S_ISDIR(mode))
 449                         mode |= S_ISGID;
 450         } else {
 451                 ri->gid = cpu_to_je16(from_kgid(&init_user_ns, current_fsgid()));
 452         }
 453
 454         /* POSIX ACLs have to be processed now, at least partly.
 455            The umask is only applied if there's no default ACL */
 456         ret = jffs2_init_acl_pre(dir_i, inode, &mode);
 457         if (ret) {
 458                 mutex_unlock(&f->sem);
 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                 mutex_unlock(&f->sem);
 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(inode);
 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                 mutex_unlock(&f->sem);
 483                 make_bad_inode(inode);
 484                 iput(inode);
 485                 return ERR_PTR(-EINVAL);
 486         }
 487
 488         return inode;
 489 }
 490
 491 static int calculate_inocache_hashsize(uint32_t flash_size)
 492 {
 493         /*
 494          * Pick a inocache hash size based on the size of the medium.
 495          * Count how many megabytes we're dealing with, apply a hashsize twice
 496          * that size, but rounding down to the usual big powers of 2. And keep
 497          * to sensible bounds.
 498          */
 499
 500         int size_mb = flash_size / 1024 / 1024;
 501         int hashsize = (size_mb * 2) & ~0x3f;
 502
 503         if (hashsize < INOCACHE_HASHSIZE_MIN)
 504                 return INOCACHE_HASHSIZE_MIN;
 505         if (hashsize > INOCACHE_HASHSIZE_MAX)
 506                 return INOCACHE_HASHSIZE_MAX;
 507
 508         return hashsize;
 509 }
 510
 511 int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
 512 {
 513         struct jffs2_sb_info *c;
 514         struct inode *root_i;
 515         int ret;
 516         size_t blocks;
 517
 518         c = JFFS2_SB_INFO(sb);
 519
 520         /* Do not support the MLC nand */
 521         if (c->mtd->type == MTD_MLCNANDFLASH)
 522                 return -EINVAL;
 523
 524 #ifndef CONFIG_JFFS2_FS_WRITEBUFFER
 525         if (c->mtd->type == MTD_NANDFLASH) {
 526                 pr_err("Cannot operate on NAND flash unless jffs2 NAND support is compiled in\n");
 527                 return -EINVAL;
 528         }
 529         if (c->mtd->type == MTD_DATAFLASH) {
 530                 pr_err("Cannot operate on DataFlash unless jffs2 DataFlash support is compiled in\n");
 531                 return -EINVAL;
 532         }
 533 #endif
 534
 535         c->flash_size = c->mtd->size;
 536         c->sector_size = c->mtd->erasesize;
 537         blocks = c->flash_size / c->sector_size;
 538
 539         /*
 540          * Size alignment check
 541          */
 542         if ((c->sector_size * blocks) != c->flash_size) {
 543                 c->flash_size = c->sector_size * blocks;
 544                 pr_info("Flash size not aligned to erasesize, reducing to %dKiB\n",
 545                         c->flash_size / 1024);
 546         }
 547
 548         if (c->flash_size < 5*c->sector_size) {
 549                 pr_err("Too few erase blocks (%d)\n",
 550                        c->flash_size / c->sector_size);
 551                 return -EINVAL;
 552         }
 553
 554         c->cleanmarker_size = sizeof(struct jffs2_unknown_node);
 555
 556         /* NAND (or other bizarre) flash... do setup accordingly */
 557         ret = jffs2_flash_setup(c);
 558         if (ret)
 559                 return ret;
 560
 561         c->inocache_hashsize = calculate_inocache_hashsize(c->flash_size);
 562         c->inocache_list = kcalloc(c->inocache_hashsize, sizeof(struct jffs2_inode_cache *), GFP_KERNEL);
 563         if (!c->inocache_list) {
 564                 ret = -ENOMEM;
 565                 goto out_wbuf;
 566         }
 567
 568         jffs2_init_xattr_subsystem(c);
 569
 570         if ((ret = jffs2_do_mount_fs(c)))
 571                 goto out_inohash;
 572
 573         jffs2_dbg(1, "%s(): Getting root inode\n", __func__);
 574         root_i = jffs2_iget(sb, 1);
 575         if (IS_ERR(root_i)) {
 576                 jffs2_dbg(1, "get root inode failed\n");
 577                 ret = PTR_ERR(root_i);
 578                 goto out_root;
 579         }
 580
 581         ret = -ENOMEM;
 582
 583         jffs2_dbg(1, "%s(): d_make_root()\n", __func__);
 584         sb->s_root = d_make_root(root_i);
 585         if (!sb->s_root)
 586                 goto out_root;
 587
 588         sb->s_maxbytes = 0xFFFFFFFF;
 589         sb->s_blocksize = PAGE_SIZE;
 590         sb->s_blocksize_bits = PAGE_SHIFT;
 591         sb->s_magic = JFFS2_SUPER_MAGIC;
 592         if (!sb_rdonly(sb))
 593                 jffs2_start_garbage_collect_thread(c);
 594         return 0;
 595
 596 out_root:
 597         jffs2_free_ino_caches(c);
 598         jffs2_free_raw_node_refs(c);
 599         kvfree(c->blocks);
 600  out_inohash:
 601         jffs2_clear_xattr_subsystem(c);
 602         kfree(c->inocache_list);
 603  out_wbuf:
 604         jffs2_flash_cleanup(c);
 605
 606         return ret;
 607 }
 608
 609 void jffs2_gc_release_inode(struct jffs2_sb_info *c,
 610                                    struct jffs2_inode_info *f)
 611 {
 612         iput(OFNI_EDONI_2SFFJ(f));
 613 }
 614
 615 struct jffs2_inode_info *jffs2_gc_fetch_inode(struct jffs2_sb_info *c,
 616                                               int inum, int unlinked)
 617 {
 618         struct inode *inode;
 619         struct jffs2_inode_cache *ic;
 620
 621         if (unlinked) {
 622                 /* The inode has zero nlink but its nodes weren't yet marked
 623                    obsolete. This has to be because we're still waiting for
 624                    the final (close() and) iput() to happen.
 625
 626                    There's a possibility that the final iput() could have
 627                    happened while we were contemplating. In order to ensure
 628                    that we don't cause a new read_inode() (which would fail)
 629                    for the inode in question, we use ilookup() in this case
 630                    instead of iget().
 631
 632                    The nlink can't _become_ zero at this point because we're
 633                    holding the alloc_sem, and jffs2_do_unlink() would also
 634                    need that while decrementing nlink on any inode.
 635                 */
 636                 inode = ilookup(OFNI_BS_2SFFJ(c), inum);
 637                 if (!inode) {
 638                         jffs2_dbg(1, "ilookup() failed for ino #%u; inode is probably deleted.\n",
 639                                   inum);
 640
 641                         spin_lock(&c->inocache_lock);
 642                         ic = jffs2_get_ino_cache(c, inum);
 643                         if (!ic) {
 644                                 jffs2_dbg(1, "Inode cache for ino #%u is gone\n",
 645                                           inum);
 646                                 spin_unlock(&c->inocache_lock);
 647                                 return NULL;
 648                         }
 649                         if (ic->state != INO_STATE_CHECKEDABSENT) {
 650                                 /* Wait for progress. Don't just loop */
 651                                 jffs2_dbg(1, "Waiting for ino #%u in state %d\n",
 652                                           ic->ino, ic->state);
 653                                 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
 654                         } else {
 655                                 spin_unlock(&c->inocache_lock);
 656                         }
 657
 658                         return NULL;
 659                 }
 660         } else {
 661                 /* Inode has links to it still; they're not going away because
 662                    jffs2_do_unlink() would need the alloc_sem and we have it.
 663                    Just iget() it, and if read_inode() is necessary that's OK.
 664                 */
 665                 inode = jffs2_iget(OFNI_BS_2SFFJ(c), inum);
 666                 if (IS_ERR(inode))
 667                         return ERR_CAST(inode);
 668         }
 669         if (is_bad_inode(inode)) {
 670                 pr_notice("Eep. read_inode() failed for ino #%u. unlinked %d\n",
 671                           inum, unlinked);
 672                 /* NB. This will happen again. We need to do something appropriate here. */
 673                 iput(inode);
 674                 return ERR_PTR(-EIO);
 675         }
 676
 677         return JFFS2_INODE_INFO(inode);
 678 }
 679
 680 unsigned char *jffs2_gc_fetch_page(struct jffs2_sb_info *c,
 681                                    struct jffs2_inode_info *f,
 682                                    unsigned long offset,
 683                                    unsigned long *priv)
 684 {
 685         struct inode *inode = OFNI_EDONI_2SFFJ(f);
 686         struct page *pg;
 687
 688         pg = read_cache_page(inode->i_mapping, offset >> PAGE_SHIFT,
 689                              (void *)jffs2_do_readpage_unlock, inode);
 690         if (IS_ERR(pg))
 691                 return (void *)pg;
 692
 693         *priv = (unsigned long)pg;
 694         return kmap(pg);
 695 }
 696
 697 void jffs2_gc_release_page(struct jffs2_sb_info *c,
 698                            unsigned char *ptr,
 699                            unsigned long *priv)
 700 {
 701         struct page *pg = (void *)*priv;
 702
 703         kunmap(pg);
 704         put_page(pg);
 705 }
 706
 707 static int jffs2_flash_setup(struct jffs2_sb_info *c) {
 708         int ret = 0;
 709
 710         if (jffs2_cleanmarker_oob(c)) {
 711                 /* NAND flash... do setup accordingly */
 712                 ret = jffs2_nand_flash_setup(c);
 713                 if (ret)
 714                         return ret;
 715         }
 716
 717         /* and Dataflash */
 718         if (jffs2_dataflash(c)) {
 719                 ret = jffs2_dataflash_setup(c);
 720                 if (ret)
 721                         return ret;
 722         }
 723
 724         /* and Intel "Sibley" flash */
 725         if (jffs2_nor_wbuf_flash(c)) {
 726                 ret = jffs2_nor_wbuf_flash_setup(c);
 727                 if (ret)
 728                         return ret;
 729         }
 730
 731         /* and an UBI volume */
 732         if (jffs2_ubivol(c)) {
 733                 ret = jffs2_ubivol_setup(c);
 734                 if (ret)
 735                         return ret;
 736         }
 737
 738         return ret;
 739 }
 740
 741 void jffs2_flash_cleanup(struct jffs2_sb_info *c) {
 742
 743         if (jffs2_cleanmarker_oob(c)) {
 744                 jffs2_nand_flash_cleanup(c);
 745         }
 746
 747         /* and DataFlash */
 748         if (jffs2_dataflash(c)) {
 749                 jffs2_dataflash_cleanup(c);
 750         }
 751
 752         /* and Intel "Sibley" flash */
 753         if (jffs2_nor_wbuf_flash(c)) {
 754                 jffs2_nor_wbuf_flash_cleanup(c);
 755         }
 756
 757         /* and an UBI volume */
 758         if (jffs2_ubivol(c)) {
 759                 jffs2_ubivol_cleanup(c);
 760         }
 761 }