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         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_rdonly(sb))
 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_rdonly(sb)) {
 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 & SB_RDONLY))
 413                 jffs2_start_garbage_collect_thread(c);
 414
 415         *flags |= SB_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                 mutex_unlock(&f->sem);
 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                 mutex_unlock(&f->sem);
 467                 make_bad_inode(inode);
 468                 iput(inode);
 469                 return ERR_PTR(ret);
 470         }
 471         set_nlink(inode, 1);
 472         inode->i_ino = je32_to_cpu(ri->ino);
 473         inode->i_mode = jemode_to_cpu(ri->mode);
 474         i_gid_write(inode, je16_to_cpu(ri->gid));
 475         i_uid_write(inode, je16_to_cpu(ri->uid));
 476         inode->i_atime = inode->i_ctime = inode->i_mtime = current_time(inode);
 477         ri->atime = ri->mtime = ri->ctime = cpu_to_je32(I_SEC(inode->i_mtime));
 478
 479         inode->i_blocks = 0;
 480         inode->i_size = 0;
 481
 482         if (insert_inode_locked(inode) < 0) {
 483                 mutex_unlock(&f->sem);
 484                 make_bad_inode(inode);
 485                 iput(inode);
 486                 return ERR_PTR(-EINVAL);
 487         }
 488
 489         return inode;
 490 }
 491
 492 static int calculate_inocache_hashsize(uint32_t flash_size)
 493 {
 494         /*
 495          * Pick a inocache hash size based on the size of the medium.
 496          * Count how many megabytes we're dealing with, apply a hashsize twice
 497          * that size, but rounding down to the usual big powers of 2. And keep
 498          * to sensible bounds.
 499          */
 500
 501         int size_mb = flash_size / 1024 / 1024;
 502         int hashsize = (size_mb * 2) & ~0x3f;
 503
 504         if (hashsize < INOCACHE_HASHSIZE_MIN)
 505                 return INOCACHE_HASHSIZE_MIN;
 506         if (hashsize > INOCACHE_HASHSIZE_MAX)
 507                 return INOCACHE_HASHSIZE_MAX;
 508
 509         return hashsize;
 510 }
 511
 512 int jffs2_do_fill_super(struct super_block *sb, void *data, int silent)
 513 {
 514         struct jffs2_sb_info *c;
 515         struct inode *root_i;
 516         int ret;
 517         size_t blocks;
 518
 519         c = JFFS2_SB_INFO(sb);
 520
 521         /* Do not support the MLC nand */
 522         if (c->mtd->type == MTD_MLCNANDFLASH)
 523                 return -EINVAL;
 524
 525 #ifndef CONFIG_JFFS2_FS_WRITEBUFFER
 526         if (c->mtd->type == MTD_NANDFLASH) {
 527                 pr_err("Cannot operate on NAND flash unless jffs2 NAND support is compiled in\n");
 528                 return -EINVAL;
 529         }
 530         if (c->mtd->type == MTD_DATAFLASH) {
 531                 pr_err("Cannot operate on DataFlash unless jffs2 DataFlash support is compiled in\n");
 532                 return -EINVAL;
 533         }
 534 #endif
 535
 536         c->flash_size = c->mtd->size;
 537         c->sector_size = c->mtd->erasesize;
 538         blocks = c->flash_size / c->sector_size;
 539
 540         /*
 541          * Size alignment check
 542          */
 543         if ((c->sector_size * blocks) != c->flash_size) {
 544                 c->flash_size = c->sector_size * blocks;
 545                 pr_info("Flash size not aligned to erasesize, reducing to %dKiB\n",
 546                         c->flash_size / 1024);
 547         }
 548
 549         if (c->flash_size < 5*c->sector_size) {
 550                 pr_err("Too few erase blocks (%d)\n",
 551                        c->flash_size / c->sector_size);
 552                 return -EINVAL;
 553         }
 554
 555         c->cleanmarker_size = sizeof(struct jffs2_unknown_node);
 556
 557         /* NAND (or other bizarre) flash... do setup accordingly */
 558         ret = jffs2_flash_setup(c);
 559         if (ret)
 560                 return ret;
 561
 562         c->inocache_hashsize = calculate_inocache_hashsize(c->flash_size);
 563         c->inocache_list = kcalloc(c->inocache_hashsize, sizeof(struct jffs2_inode_cache *), GFP_KERNEL);
 564         if (!c->inocache_list) {
 565                 ret = -ENOMEM;
 566                 goto out_wbuf;
 567         }
 568
 569         jffs2_init_xattr_subsystem(c);
 570
 571         if ((ret = jffs2_do_mount_fs(c)))
 572                 goto out_inohash;
 573
 574         jffs2_dbg(1, "%s(): Getting root inode\n", __func__);
 575         root_i = jffs2_iget(sb, 1);
 576         if (IS_ERR(root_i)) {
 577                 jffs2_dbg(1, "get root inode failed\n");
 578                 ret = PTR_ERR(root_i);
 579                 goto out_root;
 580         }
 581
 582         ret = -ENOMEM;
 583
 584         jffs2_dbg(1, "%s(): d_make_root()\n", __func__);
 585         sb->s_root = d_make_root(root_i);
 586         if (!sb->s_root)
 587                 goto out_root;
 588
 589         sb->s_maxbytes = 0xFFFFFFFF;
 590         sb->s_blocksize = PAGE_SIZE;
 591         sb->s_blocksize_bits = PAGE_SHIFT;
 592         sb->s_magic = JFFS2_SUPER_MAGIC;
 593         if (!sb_rdonly(sb))
 594                 jffs2_start_garbage_collect_thread(c);
 595         return 0;
 596
 597 out_root:
 598         jffs2_free_ino_caches(c);
 599         jffs2_free_raw_node_refs(c);
 600         kvfree(c->blocks);
 601  out_inohash:
 602         jffs2_clear_xattr_subsystem(c);
 603         kfree(c->inocache_list);
 604  out_wbuf:
 605         jffs2_flash_cleanup(c);
 606
 607         return ret;
 608 }
 609
 610 void jffs2_gc_release_inode(struct jffs2_sb_info *c,
 611                                    struct jffs2_inode_info *f)
 612 {
 613         iput(OFNI_EDONI_2SFFJ(f));
 614 }
 615
 616 struct jffs2_inode_info *jffs2_gc_fetch_inode(struct jffs2_sb_info *c,
 617                                               int inum, int unlinked)
 618 {
 619         struct inode *inode;
 620         struct jffs2_inode_cache *ic;
 621
 622         if (unlinked) {
 623                 /* The inode has zero nlink but its nodes weren't yet marked
 624                    obsolete. This has to be because we're still waiting for
 625                    the final (close() and) iput() to happen.
 626
 627                    There's a possibility that the final iput() could have
 628                    happened while we were contemplating. In order to ensure
 629                    that we don't cause a new read_inode() (which would fail)
 630                    for the inode in question, we use ilookup() in this case
 631                    instead of iget().
 632
 633                    The nlink can't _become_ zero at this point because we're
 634                    holding the alloc_sem, and jffs2_do_unlink() would also
 635                    need that while decrementing nlink on any inode.
 636                 */
 637                 inode = ilookup(OFNI_BS_2SFFJ(c), inum);
 638                 if (!inode) {
 639                         jffs2_dbg(1, "ilookup() failed for ino #%u; inode is probably deleted.\n",
 640                                   inum);
 641
 642                         spin_lock(&c->inocache_lock);
 643                         ic = jffs2_get_ino_cache(c, inum);
 644                         if (!ic) {
 645                                 jffs2_dbg(1, "Inode cache for ino #%u is gone\n",
 646                                           inum);
 647                                 spin_unlock(&c->inocache_lock);
 648                                 return NULL;
 649                         }
 650                         if (ic->state != INO_STATE_CHECKEDABSENT) {
 651                                 /* Wait for progress. Don't just loop */
 652                                 jffs2_dbg(1, "Waiting for ino #%u in state %d\n",
 653                                           ic->ino, ic->state);
 654                                 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
 655                         } else {
 656                                 spin_unlock(&c->inocache_lock);
 657                         }
 658
 659                         return NULL;
 660                 }
 661         } else {
 662                 /* Inode has links to it still; they're not going away because
 663                    jffs2_do_unlink() would need the alloc_sem and we have it.
 664                    Just iget() it, and if read_inode() is necessary that's OK.
 665                 */
 666                 inode = jffs2_iget(OFNI_BS_2SFFJ(c), inum);
 667                 if (IS_ERR(inode))
 668                         return ERR_CAST(inode);
 669         }
 670         if (is_bad_inode(inode)) {
 671                 pr_notice("Eep. read_inode() failed for ino #%u. unlinked %d\n",
 672                           inum, unlinked);
 673                 /* NB. This will happen again. We need to do something appropriate here. */
 674                 iput(inode);
 675                 return ERR_PTR(-EIO);
 676         }
 677
 678         return JFFS2_INODE_INFO(inode);
 679 }
 680
 681 unsigned char *jffs2_gc_fetch_page(struct jffs2_sb_info *c,
 682                                    struct jffs2_inode_info *f,
 683                                    unsigned long offset,
 684                                    unsigned long *priv)
 685 {
 686         struct inode *inode = OFNI_EDONI_2SFFJ(f);
 687         struct page *pg;
 688
 689         pg = read_cache_page(inode->i_mapping, offset >> PAGE_SHIFT,
 690                              (void *)jffs2_do_readpage_unlock, inode);
 691         if (IS_ERR(pg))
 692                 return (void *)pg;
 693
 694         *priv = (unsigned long)pg;
 695         return kmap(pg);
 696 }
 697
 698 void jffs2_gc_release_page(struct jffs2_sb_info *c,
 699                            unsigned char *ptr,
 700                            unsigned long *priv)
 701 {
 702         struct page *pg = (void *)*priv;
 703
 704         kunmap(pg);
 705         put_page(pg);
 706 }
 707
 708 static int jffs2_flash_setup(struct jffs2_sb_info *c) {
 709         int ret = 0;
 710
 711         if (jffs2_cleanmarker_oob(c)) {
 712                 /* NAND flash... do setup accordingly */
 713                 ret = jffs2_nand_flash_setup(c);
 714                 if (ret)
 715                         return ret;
 716         }
 717
 718         /* and Dataflash */
 719         if (jffs2_dataflash(c)) {
 720                 ret = jffs2_dataflash_setup(c);
 721                 if (ret)
 722                         return ret;
 723         }
 724
 725         /* and Intel "Sibley" flash */
 726         if (jffs2_nor_wbuf_flash(c)) {
 727                 ret = jffs2_nor_wbuf_flash_setup(c);
 728                 if (ret)
 729                         return ret;
 730         }
 731
 732         /* and an UBI volume */
 733         if (jffs2_ubivol(c)) {
 734                 ret = jffs2_ubivol_setup(c);
 735                 if (ret)
 736                         return ret;
 737         }
 738
 739         return ret;
 740 }
 741
 742 void jffs2_flash_cleanup(struct jffs2_sb_info *c) {
 743
 744         if (jffs2_cleanmarker_oob(c)) {
 745                 jffs2_nand_flash_cleanup(c);
 746         }
 747
 748         /* and DataFlash */
 749         if (jffs2_dataflash(c)) {
 750                 jffs2_dataflash_cleanup(c);
 751         }
 752
 753         /* and Intel "Sibley" flash */
 754         if (jffs2_nor_wbuf_flash(c)) {
 755                 jffs2_nor_wbuf_flash_cleanup(c);
 756         }
 757
 758         /* and an UBI volume */
 759         if (jffs2_ubivol(c)) {
 760                 jffs2_ubivol_cleanup(c);
 761         }
 762 }