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/fs_context.h>
  21 #include <linux/list.h>
  22 #include <linux/mtd/mtd.h>
  23 #include <linux/pagemap.h>
  24 #include <linux/slab.h>
  25 #include <linux/vmalloc.h>
  26 #include <linux/vfs.h>
  27 #include <linux/crc32.h>
  28 #include "nodelist.h"
  29
  30 static int jffs2_flash_setup(struct jffs2_sb_info *c);
  31
  32 int jffs2_do_setattr (struct inode *inode, struct iattr *iattr)
  33 {
  34         struct jffs2_full_dnode *old_metadata, *new_metadata;
  35         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
  36         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
  37         struct jffs2_raw_inode *ri;
  38         union jffs2_device_node dev;
  39         unsigned char *mdata = NULL;
  40         int mdatalen = 0;
  41         unsigned int ivalid;
  42         uint32_t alloclen;
  43         int ret;
  44         int alloc_type = ALLOC_NORMAL;
  45
  46         jffs2_dbg(1, "%s(): ino #%lu\n", __func__, inode->i_ino);
  47
  48         /* Special cases - we don't want more than one data node
  49            for these types on the medium at any time. So setattr
  50            must read the original data associated with the node
  51            (i.e. the device numbers or the target name) and write
  52            it out again with the appropriate data attached */
  53         if (S_ISBLK(inode->i_mode) || S_ISCHR(inode->i_mode)) {
  54                 /* For these, we don't actually need to read the old node */
  55                 mdatalen = jffs2_encode_dev(&dev, inode->i_rdev);
  56                 mdata = (char *)&dev;
  57                 jffs2_dbg(1, "%s(): Writing %d bytes of kdev_t\n",
  58                           __func__, mdatalen);
  59         } else if (S_ISLNK(inode->i_mode)) {
  60                 mutex_lock(&f->sem);
  61                 mdatalen = f->metadata->size;
  62                 mdata = kmalloc(f->metadata->size, GFP_USER);
  63                 if (!mdata) {
  64                         mutex_unlock(&f->sem);
  65                         return -ENOMEM;
  66                 }
  67                 ret = jffs2_read_dnode(c, f, f->metadata, mdata, 0, mdatalen);
  68                 if (ret) {
  69                         mutex_unlock(&f->sem);
  70                         kfree(mdata);
  71                         return ret;
  72                 }
  73                 mutex_unlock(&f->sem);
  74                 jffs2_dbg(1, "%s(): Writing %d bytes of symlink target\n",
  75                           __func__, mdatalen);
  76         }
  77
  78         ri = jffs2_alloc_raw_inode();
  79         if (!ri) {
  80                 if (S_ISLNK(inode->i_mode))
  81                         kfree(mdata);
  82                 return -ENOMEM;
  83         }
  84
  85         ret = jffs2_reserve_space(c, sizeof(*ri) + mdatalen, &alloclen,
  86                                   ALLOC_NORMAL, JFFS2_SUMMARY_INODE_SIZE);
  87         if (ret) {
  88                 jffs2_free_raw_inode(ri);
  89                 if (S_ISLNK(inode->i_mode))
  90                          kfree(mdata);
  91                 return ret;
  92         }
  93         mutex_lock(&f->sem);
  94         ivalid = iattr->ia_valid;
  95
  96         ri->magic = cpu_to_je16(JFFS2_MAGIC_BITMASK);
  97         ri->nodetype = cpu_to_je16(JFFS2_NODETYPE_INODE);
  98         ri->totlen = cpu_to_je32(sizeof(*ri) + mdatalen);
  99         ri->hdr_crc = cpu_to_je32(crc32(0, ri, sizeof(struct jffs2_unknown_node)-4));
 100
 101         ri->ino = cpu_to_je32(inode->i_ino);
 102         ri->version = cpu_to_je32(++f->highest_version);
 103
 104         ri->uid = cpu_to_je16((ivalid & ATTR_UID)?
 105                 from_kuid(&init_user_ns, iattr->ia_uid):i_uid_read(inode));
 106         ri->gid = cpu_to_je16((ivalid & ATTR_GID)?
 107                 from_kgid(&init_user_ns, iattr->ia_gid):i_gid_read(inode));
 108
 109         if (ivalid & ATTR_MODE)
 110                 ri->mode = cpu_to_jemode(iattr->ia_mode);
 111         else
 112                 ri->mode = cpu_to_jemode(inode->i_mode);
 113
 114
 115         ri->isize = cpu_to_je32((ivalid & ATTR_SIZE)?iattr->ia_size:inode->i_size);
 116         ri->atime = cpu_to_je32(I_SEC((ivalid & ATTR_ATIME)?iattr->ia_atime:inode->i_atime));
 117         ri->mtime = cpu_to_je32(I_SEC((ivalid & ATTR_MTIME)?iattr->ia_mtime:inode->i_mtime));
 118         ri->ctime = cpu_to_je32(I_SEC((ivalid & ATTR_CTIME)?iattr->ia_ctime:inode->i_ctime));
 119
 120         ri->offset = cpu_to_je32(0);
 121         ri->csize = ri->dsize = cpu_to_je32(mdatalen);
 122         ri->compr = JFFS2_COMPR_NONE;
 123         if (ivalid & ATTR_SIZE && inode->i_size < iattr->ia_size) {
 124                 /* It's an extension. Make it a hole node */
 125                 ri->compr = JFFS2_COMPR_ZERO;
 126                 ri->dsize = cpu_to_je32(iattr->ia_size - inode->i_size);
 127                 ri->offset = cpu_to_je32(inode->i_size);
 128         } else if (ivalid & ATTR_SIZE && !iattr->ia_size) {
 129                 /* For truncate-to-zero, treat it as deletion because
 130                    it'll always be obsoleting all previous nodes */
 131                 alloc_type = ALLOC_DELETION;
 132         }
 133         ri->node_crc = cpu_to_je32(crc32(0, ri, sizeof(*ri)-8));
 134         if (mdatalen)
 135                 ri->data_crc = cpu_to_je32(crc32(0, mdata, mdatalen));
 136         else
 137                 ri->data_crc = cpu_to_je32(0);
 138
 139         new_metadata = jffs2_write_dnode(c, f, ri, mdata, mdatalen, alloc_type);
 140         if (S_ISLNK(inode->i_mode))
 141                 kfree(mdata);
 142
 143         if (IS_ERR(new_metadata)) {
 144                 jffs2_complete_reservation(c);
 145                 jffs2_free_raw_inode(ri);
 146                 mutex_unlock(&f->sem);
 147                 return PTR_ERR(new_metadata);
 148         }
 149         /* It worked. Update the inode */
 150         inode->i_atime = ITIME(je32_to_cpu(ri->atime));
 151         inode->i_ctime = ITIME(je32_to_cpu(ri->ctime));
 152         inode->i_mtime = ITIME(je32_to_cpu(ri->mtime));
 153         inode->i_mode = jemode_to_cpu(ri->mode);
 154         i_uid_write(inode, je16_to_cpu(ri->uid));
 155         i_gid_write(inode, je16_to_cpu(ri->gid));
 156
 157
 158         old_metadata = f->metadata;
 159
 160         if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size)
 161                 jffs2_truncate_fragtree (c, &f->fragtree, iattr->ia_size);
 162
 163         if (ivalid & ATTR_SIZE && inode->i_size < iattr->ia_size) {
 164                 jffs2_add_full_dnode_to_inode(c, f, new_metadata);
 165                 inode->i_size = iattr->ia_size;
 166                 inode->i_blocks = (inode->i_size + 511) >> 9;
 167                 f->metadata = NULL;
 168         } else {
 169                 f->metadata = new_metadata;
 170         }
 171         if (old_metadata) {
 172                 jffs2_mark_node_obsolete(c, old_metadata->raw);
 173                 jffs2_free_full_dnode(old_metadata);
 174         }
 175         jffs2_free_raw_inode(ri);
 176
 177         mutex_unlock(&f->sem);
 178         jffs2_complete_reservation(c);
 179
 180         /* We have to do the truncate_setsize() without f->sem held, since
 181            some pages may be locked and waiting for it in readpage().
 182            We are protected from a simultaneous write() extending i_size
 183            back past iattr->ia_size, because do_truncate() holds the
 184            generic inode semaphore. */
 185         if (ivalid & ATTR_SIZE && inode->i_size > iattr->ia_size) {
 186                 truncate_setsize(inode, iattr->ia_size);
 187                 inode->i_blocks = (inode->i_size + 511) >> 9;
 188         }
 189
 190         return 0;
 191 }
 192
 193 int jffs2_setattr(struct dentry *dentry, struct iattr *iattr)
 194 {
 195         struct inode *inode = d_inode(dentry);
 196         int rc;
 197
 198         rc = setattr_prepare(dentry, iattr);
 199         if (rc)
 200                 return rc;
 201
 202         rc = jffs2_do_setattr(inode, iattr);
 203         if (!rc && (iattr->ia_valid & ATTR_MODE))
 204                 rc = posix_acl_chmod(inode, inode->i_mode);
 205
 206         return rc;
 207 }
 208
 209 int jffs2_statfs(struct dentry *dentry, struct kstatfs *buf)
 210 {
 211         struct jffs2_sb_info *c = JFFS2_SB_INFO(dentry->d_sb);
 212         unsigned long avail;
 213
 214         buf->f_type = JFFS2_SUPER_MAGIC;
 215         buf->f_bsize = 1 << PAGE_SHIFT;
 216         buf->f_blocks = c->flash_size >> PAGE_SHIFT;
 217         buf->f_files = 0;
 218         buf->f_ffree = 0;
 219         buf->f_namelen = JFFS2_MAX_NAME_LEN;
 220         buf->f_fsid.val[0] = JFFS2_SUPER_MAGIC;
 221         buf->f_fsid.val[1] = c->mtd->index;
 222
 223         spin_lock(&c->erase_completion_lock);
 224         avail = c->dirty_size + c->free_size;
 225         if (avail > c->sector_size * c->resv_blocks_write)
 226                 avail -= c->sector_size * c->resv_blocks_write;
 227         else
 228                 avail = 0;
 229         spin_unlock(&c->erase_completion_lock);
 230
 231         buf->f_bavail = buf->f_bfree = avail >> PAGE_SHIFT;
 232
 233         return 0;
 234 }
 235
 236
 237 void jffs2_evict_inode (struct inode *inode)
 238 {
 239         /* We can forget about this inode for now - drop all
 240          *  the nodelists associated with it, etc.
 241          */
 242         struct jffs2_sb_info *c = JFFS2_SB_INFO(inode->i_sb);
 243         struct jffs2_inode_info *f = JFFS2_INODE_INFO(inode);
 244
 245         jffs2_dbg(1, "%s(): ino #%lu mode %o\n",
 246                   __func__, inode->i_ino, inode->i_mode);
 247         truncate_inode_pages_final(&inode->i_data);
 248         clear_inode(inode);
 249         jffs2_do_clear_inode(c, f);
 250 }
 251
 252 struct inode *jffs2_iget(struct super_block *sb, unsigned long ino)
 253 {
 254         struct jffs2_inode_info *f;
 255         struct jffs2_sb_info *c;
 256         struct jffs2_raw_inode latest_node;
 257         union jffs2_device_node jdev;
 258         struct inode *inode;
 259         dev_t rdev = 0;
 260         int ret;
 261
 262         jffs2_dbg(1, "%s(): ino == %lu\n", __func__, ino);
 263
 264         inode = iget_locked(sb, ino);
 265         if (!inode)
 266                 return ERR_PTR(-ENOMEM);
 267         if (!(inode->i_state & I_NEW))
 268                 return inode;
 269
 270         f = JFFS2_INODE_INFO(inode);
 271         c = JFFS2_SB_INFO(inode->i_sb);
 272
 273         jffs2_init_inode_info(f);
 274         mutex_lock(&f->sem);
 275
 276         ret = jffs2_do_read_inode(c, f, inode->i_ino, &latest_node);
 277         if (ret)
 278                 goto error;
 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                 inode->i_link = f->target;
 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                 /* fall through */
 345
 346         case S_IFSOCK:
 347         case S_IFIFO:
 348                 inode->i_op = &jffs2_file_inode_operations;
 349                 init_special_inode(inode, inode->i_mode, rdev);
 350                 break;
 351
 352         default:
 353                 pr_warn("%s(): Bogus i_mode %o for ino %lu\n",
 354                         __func__, inode->i_mode, (unsigned long)inode->i_ino);
 355         }
 356
 357         mutex_unlock(&f->sem);
 358
 359         jffs2_dbg(1, "jffs2_read_inode() returning\n");
 360         unlock_new_inode(inode);
 361         return inode;
 362
 363 error_io:
 364         ret = -EIO;
 365 error:
 366         mutex_unlock(&f->sem);
 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, struct fs_context *fc)
 396 {
 397         struct jffs2_sb_info *c = JFFS2_SB_INFO(sb);
 398
 399         if (c->flags & JFFS2_SB_FLAG_RO && !sb_rdonly(sb))
 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_rdonly(sb)) {
 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 (!(fc->sb_flags & SB_RDONLY))
 414                 jffs2_start_garbage_collect_thread(c);
 415
 416         fc->sb_flags |= SB_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                 mutex_unlock(&f->sem);
 461                 make_bad_inode(inode);
 462                 iput(inode);
 463                 return ERR_PTR(ret);
 464         }
 465         ret = jffs2_do_new_inode (c, f, mode, ri);
 466         if (ret) {
 467                 mutex_unlock(&f->sem);
 468                 make_bad_inode(inode);
 469                 iput(inode);
 470                 return ERR_PTR(ret);
 471         }
 472         set_nlink(inode, 1);
 473         inode->i_ino = je32_to_cpu(ri->ino);
 474         inode->i_mode = jemode_to_cpu(ri->mode);
 475         i_gid_write(inode, je16_to_cpu(ri->gid));
 476         i_uid_write(inode, je16_to_cpu(ri->uid));
 477         inode->i_atime = inode->i_ctime = inode->i_mtime = current_time(inode);
 478         ri->atime = ri->mtime = ri->ctime = cpu_to_je32(I_SEC(inode->i_mtime));
 479
 480         inode->i_blocks = 0;
 481         inode->i_size = 0;
 482
 483         if (insert_inode_locked(inode) < 0) {
 484                 mutex_unlock(&f->sem);
 485                 make_bad_inode(inode);
 486                 iput(inode);
 487                 return ERR_PTR(-EINVAL);
 488         }
 489
 490         return inode;
 491 }
 492
 493 static int calculate_inocache_hashsize(uint32_t flash_size)
 494 {
 495         /*
 496          * Pick a inocache hash size based on the size of the medium.
 497          * Count how many megabytes we're dealing with, apply a hashsize twice
 498          * that size, but rounding down to the usual big powers of 2. And keep
 499          * to sensible bounds.
 500          */
 501
 502         int size_mb = flash_size / 1024 / 1024;
 503         int hashsize = (size_mb * 2) & ~0x3f;
 504
 505         if (hashsize < INOCACHE_HASHSIZE_MIN)
 506                 return INOCACHE_HASHSIZE_MIN;
 507         if (hashsize > INOCACHE_HASHSIZE_MAX)
 508                 return INOCACHE_HASHSIZE_MAX;
 509
 510         return hashsize;
 511 }
 512
 513 int jffs2_do_fill_super(struct super_block *sb, struct fs_context *fc)
 514 {
 515         struct jffs2_sb_info *c;
 516         struct inode *root_i;
 517         int ret;
 518         size_t blocks;
 519
 520         c = JFFS2_SB_INFO(sb);
 521
 522         /* Do not support the MLC nand */
 523         if (c->mtd->type == MTD_MLCNANDFLASH)
 524                 return -EINVAL;
 525
 526 #ifndef CONFIG_JFFS2_FS_WRITEBUFFER
 527         if (c->mtd->type == MTD_NANDFLASH) {
 528                 errorf(fc, "Cannot operate on NAND flash unless jffs2 NAND support is compiled in");
 529                 return -EINVAL;
 530         }
 531         if (c->mtd->type == MTD_DATAFLASH) {
 532                 errorf(fc, "Cannot operate on DataFlash unless jffs2 DataFlash support is compiled in");
 533                 return -EINVAL;
 534         }
 535 #endif
 536
 537         c->flash_size = c->mtd->size;
 538         c->sector_size = c->mtd->erasesize;
 539         blocks = c->flash_size / c->sector_size;
 540
 541         /*
 542          * Size alignment check
 543          */
 544         if ((c->sector_size * blocks) != c->flash_size) {
 545                 c->flash_size = c->sector_size * blocks;
 546                 infof(fc, "Flash size not aligned to erasesize, reducing to %dKiB",
 547                       c->flash_size / 1024);
 548         }
 549
 550         if (c->flash_size < 5*c->sector_size) {
 551                 errorf(fc, "Too few erase blocks (%d)",
 552                        c->flash_size / c->sector_size);
 553                 return -EINVAL;
 554         }
 555
 556         c->cleanmarker_size = sizeof(struct jffs2_unknown_node);
 557
 558         /* NAND (or other bizarre) flash... do setup accordingly */
 559         ret = jffs2_flash_setup(c);
 560         if (ret)
 561                 return ret;
 562
 563         c->inocache_hashsize = calculate_inocache_hashsize(c->flash_size);
 564         c->inocache_list = kcalloc(c->inocache_hashsize, sizeof(struct jffs2_inode_cache *), GFP_KERNEL);
 565         if (!c->inocache_list) {
 566                 ret = -ENOMEM;
 567                 goto out_wbuf;
 568         }
 569
 570         jffs2_init_xattr_subsystem(c);
 571
 572         if ((ret = jffs2_do_mount_fs(c)))
 573                 goto out_inohash;
 574
 575         jffs2_dbg(1, "%s(): Getting root inode\n", __func__);
 576         root_i = jffs2_iget(sb, 1);
 577         if (IS_ERR(root_i)) {
 578                 jffs2_dbg(1, "get root inode failed\n");
 579                 ret = PTR_ERR(root_i);
 580                 goto out_root;
 581         }
 582
 583         ret = -ENOMEM;
 584
 585         jffs2_dbg(1, "%s(): d_make_root()\n", __func__);
 586         sb->s_root = d_make_root(root_i);
 587         if (!sb->s_root)
 588                 goto out_root;
 589
 590         sb->s_maxbytes = 0xFFFFFFFF;
 591         sb->s_blocksize = PAGE_SIZE;
 592         sb->s_blocksize_bits = PAGE_SHIFT;
 593         sb->s_magic = JFFS2_SUPER_MAGIC;
 594         sb->s_time_min = 0;
 595         sb->s_time_max = U32_MAX;
 596
 597         if (!sb_rdonly(sb))
 598                 jffs2_start_garbage_collect_thread(c);
 599         return 0;
 600
 601 out_root:
 602         jffs2_free_ino_caches(c);
 603         jffs2_free_raw_node_refs(c);
 604         kvfree(c->blocks);
 605  out_inohash:
 606         jffs2_clear_xattr_subsystem(c);
 607         kfree(c->inocache_list);
 608  out_wbuf:
 609         jffs2_flash_cleanup(c);
 610
 611         return ret;
 612 }
 613
 614 void jffs2_gc_release_inode(struct jffs2_sb_info *c,
 615                                    struct jffs2_inode_info *f)
 616 {
 617         iput(OFNI_EDONI_2SFFJ(f));
 618 }
 619
 620 struct jffs2_inode_info *jffs2_gc_fetch_inode(struct jffs2_sb_info *c,
 621                                               int inum, int unlinked)
 622 {
 623         struct inode *inode;
 624         struct jffs2_inode_cache *ic;
 625
 626         if (unlinked) {
 627                 /* The inode has zero nlink but its nodes weren't yet marked
 628                    obsolete. This has to be because we're still waiting for
 629                    the final (close() and) iput() to happen.
 630
 631                    There's a possibility that the final iput() could have
 632                    happened while we were contemplating. In order to ensure
 633                    that we don't cause a new read_inode() (which would fail)
 634                    for the inode in question, we use ilookup() in this case
 635                    instead of iget().
 636
 637                    The nlink can't _become_ zero at this point because we're
 638                    holding the alloc_sem, and jffs2_do_unlink() would also
 639                    need that while decrementing nlink on any inode.
 640                 */
 641                 inode = ilookup(OFNI_BS_2SFFJ(c), inum);
 642                 if (!inode) {
 643                         jffs2_dbg(1, "ilookup() failed for ino #%u; inode is probably deleted.\n",
 644                                   inum);
 645
 646                         spin_lock(&c->inocache_lock);
 647                         ic = jffs2_get_ino_cache(c, inum);
 648                         if (!ic) {
 649                                 jffs2_dbg(1, "Inode cache for ino #%u is gone\n",
 650                                           inum);
 651                                 spin_unlock(&c->inocache_lock);
 652                                 return NULL;
 653                         }
 654                         if (ic->state != INO_STATE_CHECKEDABSENT) {
 655                                 /* Wait for progress. Don't just loop */
 656                                 jffs2_dbg(1, "Waiting for ino #%u in state %d\n",
 657                                           ic->ino, ic->state);
 658                                 sleep_on_spinunlock(&c->inocache_wq, &c->inocache_lock);
 659                         } else {
 660                                 spin_unlock(&c->inocache_lock);
 661                         }
 662
 663                         return NULL;
 664                 }
 665         } else {
 666                 /* Inode has links to it still; they're not going away because
 667                    jffs2_do_unlink() would need the alloc_sem and we have it.
 668                    Just iget() it, and if read_inode() is necessary that's OK.
 669                 */
 670                 inode = jffs2_iget(OFNI_BS_2SFFJ(c), inum);
 671                 if (IS_ERR(inode))
 672                         return ERR_CAST(inode);
 673         }
 674         if (is_bad_inode(inode)) {
 675                 pr_notice("Eep. read_inode() failed for ino #%u. unlinked %d\n",
 676                           inum, unlinked);
 677                 /* NB. This will happen again. We need to do something appropriate here. */
 678                 iput(inode);
 679                 return ERR_PTR(-EIO);
 680         }
 681
 682         return JFFS2_INODE_INFO(inode);
 683 }
 684
 685 static int jffs2_flash_setup(struct jffs2_sb_info *c) {
 686         int ret = 0;
 687
 688         if (jffs2_cleanmarker_oob(c)) {
 689                 /* NAND flash... do setup accordingly */
 690                 ret = jffs2_nand_flash_setup(c);
 691                 if (ret)
 692                         return ret;
 693         }
 694
 695         /* and Dataflash */
 696         if (jffs2_dataflash(c)) {
 697                 ret = jffs2_dataflash_setup(c);
 698                 if (ret)
 699                         return ret;
 700         }
 701
 702         /* and Intel "Sibley" flash */
 703         if (jffs2_nor_wbuf_flash(c)) {
 704                 ret = jffs2_nor_wbuf_flash_setup(c);
 705                 if (ret)
 706                         return ret;
 707         }
 708
 709         /* and an UBI volume */
 710         if (jffs2_ubivol(c)) {
 711                 ret = jffs2_ubivol_setup(c);
 712                 if (ret)
 713                         return ret;
 714         }
 715
 716         return ret;
 717 }
 718
 719 void jffs2_flash_cleanup(struct jffs2_sb_info *c) {
 720
 721         if (jffs2_cleanmarker_oob(c)) {
 722                 jffs2_nand_flash_cleanup(c);
 723         }
 724
 725         /* and DataFlash */
 726         if (jffs2_dataflash(c)) {
 727                 jffs2_dataflash_cleanup(c);
 728         }
 729
 730         /* and Intel "Sibley" flash */
 731         if (jffs2_nor_wbuf_flash(c)) {
 732                 jffs2_nor_wbuf_flash_cleanup(c);
 733         }
 734
 735         /* and an UBI volume */
 736         if (jffs2_ubivol(c)) {
 737                 jffs2_ubivol_cleanup(c);
 738         }
 739 }