linux/fs/ntfs/inode.c
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   1/**
   2 * inode.c - NTFS kernel inode handling. Part of the Linux-NTFS project.
   3 *
   4 * Copyright (c) 2001-2007 Anton Altaparmakov
   5 *
   6 * This program/include file is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public License as published
   8 * by the Free Software Foundation; either version 2 of the License, or
   9 * (at your option) any later version.
  10 *
  11 * This program/include file is distributed in the hope that it will be
  12 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  13 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 * GNU General Public License for more details.
  15 *
  16 * You should have received a copy of the GNU General Public License
  17 * along with this program (in the main directory of the Linux-NTFS
  18 * distribution in the file COPYING); if not, write to the Free Software
  19 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  20 */
  21
  22#include <linux/buffer_head.h>
  23#include <linux/fs.h>
  24#include <linux/mm.h>
  25#include <linux/mount.h>
  26#include <linux/mutex.h>
  27#include <linux/pagemap.h>
  28#include <linux/quotaops.h>
  29#include <linux/slab.h>
  30#include <linux/log2.h>
  31
  32#include "aops.h"
  33#include "attrib.h"
  34#include "bitmap.h"
  35#include "dir.h"
  36#include "debug.h"
  37#include "inode.h"
  38#include "lcnalloc.h"
  39#include "malloc.h"
  40#include "mft.h"
  41#include "time.h"
  42#include "ntfs.h"
  43
  44/**
  45 * ntfs_test_inode - compare two (possibly fake) inodes for equality
  46 * @vi:         vfs inode which to test
  47 * @na:         ntfs attribute which is being tested with
  48 *
  49 * Compare the ntfs attribute embedded in the ntfs specific part of the vfs
  50 * inode @vi for equality with the ntfs attribute @na.
  51 *
  52 * If searching for the normal file/directory inode, set @na->type to AT_UNUSED.
  53 * @na->name and @na->name_len are then ignored.
  54 *
  55 * Return 1 if the attributes match and 0 if not.
  56 *
  57 * NOTE: This function runs with the inode->i_lock spin lock held so it is not
  58 * allowed to sleep.
  59 */
  60int ntfs_test_inode(struct inode *vi, ntfs_attr *na)
  61{
  62        ntfs_inode *ni;
  63
  64        if (vi->i_ino != na->mft_no)
  65                return 0;
  66        ni = NTFS_I(vi);
  67        /* If !NInoAttr(ni), @vi is a normal file or directory inode. */
  68        if (likely(!NInoAttr(ni))) {
  69                /* If not looking for a normal inode this is a mismatch. */
  70                if (unlikely(na->type != AT_UNUSED))
  71                        return 0;
  72        } else {
  73                /* A fake inode describing an attribute. */
  74                if (ni->type != na->type)
  75                        return 0;
  76                if (ni->name_len != na->name_len)
  77                        return 0;
  78                if (na->name_len && memcmp(ni->name, na->name,
  79                                na->name_len * sizeof(ntfschar)))
  80                        return 0;
  81        }
  82        /* Match! */
  83        return 1;
  84}
  85
  86/**
  87 * ntfs_init_locked_inode - initialize an inode
  88 * @vi:         vfs inode to initialize
  89 * @na:         ntfs attribute which to initialize @vi to
  90 *
  91 * Initialize the vfs inode @vi with the values from the ntfs attribute @na in
  92 * order to enable ntfs_test_inode() to do its work.
  93 *
  94 * If initializing the normal file/directory inode, set @na->type to AT_UNUSED.
  95 * In that case, @na->name and @na->name_len should be set to NULL and 0,
  96 * respectively. Although that is not strictly necessary as
  97 * ntfs_read_locked_inode() will fill them in later.
  98 *
  99 * Return 0 on success and -errno on error.
 100 *
 101 * NOTE: This function runs with the inode->i_lock spin lock held so it is not
 102 * allowed to sleep. (Hence the GFP_ATOMIC allocation.)
 103 */
 104static int ntfs_init_locked_inode(struct inode *vi, ntfs_attr *na)
 105{
 106        ntfs_inode *ni = NTFS_I(vi);
 107
 108        vi->i_ino = na->mft_no;
 109
 110        ni->type = na->type;
 111        if (na->type == AT_INDEX_ALLOCATION)
 112                NInoSetMstProtected(ni);
 113
 114        ni->name = na->name;
 115        ni->name_len = na->name_len;
 116
 117        /* If initializing a normal inode, we are done. */
 118        if (likely(na->type == AT_UNUSED)) {
 119                BUG_ON(na->name);
 120                BUG_ON(na->name_len);
 121                return 0;
 122        }
 123
 124        /* It is a fake inode. */
 125        NInoSetAttr(ni);
 126
 127        /*
 128         * We have I30 global constant as an optimization as it is the name
 129         * in >99.9% of named attributes! The other <0.1% incur a GFP_ATOMIC
 130         * allocation but that is ok. And most attributes are unnamed anyway,
 131         * thus the fraction of named attributes with name != I30 is actually
 132         * absolutely tiny.
 133         */
 134        if (na->name_len && na->name != I30) {
 135                unsigned int i;
 136
 137                BUG_ON(!na->name);
 138                i = na->name_len * sizeof(ntfschar);
 139                ni->name = kmalloc(i + sizeof(ntfschar), GFP_ATOMIC);
 140                if (!ni->name)
 141                        return -ENOMEM;
 142                memcpy(ni->name, na->name, i);
 143                ni->name[na->name_len] = 0;
 144        }
 145        return 0;
 146}
 147
 148typedef int (*set_t)(struct inode *, void *);
 149static int ntfs_read_locked_inode(struct inode *vi);
 150static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi);
 151static int ntfs_read_locked_index_inode(struct inode *base_vi,
 152                struct inode *vi);
 153
 154/**
 155 * ntfs_iget - obtain a struct inode corresponding to a specific normal inode
 156 * @sb:         super block of mounted volume
 157 * @mft_no:     mft record number / inode number to obtain
 158 *
 159 * Obtain the struct inode corresponding to a specific normal inode (i.e. a
 160 * file or directory).
 161 *
 162 * If the inode is in the cache, it is just returned with an increased
 163 * reference count. Otherwise, a new struct inode is allocated and initialized,
 164 * and finally ntfs_read_locked_inode() is called to read in the inode and
 165 * fill in the remainder of the inode structure.
 166 *
 167 * Return the struct inode on success. Check the return value with IS_ERR() and
 168 * if true, the function failed and the error code is obtained from PTR_ERR().
 169 */
 170struct inode *ntfs_iget(struct super_block *sb, unsigned long mft_no)
 171{
 172        struct inode *vi;
 173        int err;
 174        ntfs_attr na;
 175
 176        na.mft_no = mft_no;
 177        na.type = AT_UNUSED;
 178        na.name = NULL;
 179        na.name_len = 0;
 180
 181        vi = iget5_locked(sb, mft_no, (test_t)ntfs_test_inode,
 182                        (set_t)ntfs_init_locked_inode, &na);
 183        if (unlikely(!vi))
 184                return ERR_PTR(-ENOMEM);
 185
 186        err = 0;
 187
 188        /* If this is a freshly allocated inode, need to read it now. */
 189        if (vi->i_state & I_NEW) {
 190                err = ntfs_read_locked_inode(vi);
 191                unlock_new_inode(vi);
 192        }
 193        /*
 194         * There is no point in keeping bad inodes around if the failure was
 195         * due to ENOMEM. We want to be able to retry again later.
 196         */
 197        if (unlikely(err == -ENOMEM)) {
 198                iput(vi);
 199                vi = ERR_PTR(err);
 200        }
 201        return vi;
 202}
 203
 204/**
 205 * ntfs_attr_iget - obtain a struct inode corresponding to an attribute
 206 * @base_vi:    vfs base inode containing the attribute
 207 * @type:       attribute type
 208 * @name:       Unicode name of the attribute (NULL if unnamed)
 209 * @name_len:   length of @name in Unicode characters (0 if unnamed)
 210 *
 211 * Obtain the (fake) struct inode corresponding to the attribute specified by
 212 * @type, @name, and @name_len, which is present in the base mft record
 213 * specified by the vfs inode @base_vi.
 214 *
 215 * If the attribute inode is in the cache, it is just returned with an
 216 * increased reference count. Otherwise, a new struct inode is allocated and
 217 * initialized, and finally ntfs_read_locked_attr_inode() is called to read the
 218 * attribute and fill in the inode structure.
 219 *
 220 * Note, for index allocation attributes, you need to use ntfs_index_iget()
 221 * instead of ntfs_attr_iget() as working with indices is a lot more complex.
 222 *
 223 * Return the struct inode of the attribute inode on success. Check the return
 224 * value with IS_ERR() and if true, the function failed and the error code is
 225 * obtained from PTR_ERR().
 226 */
 227struct inode *ntfs_attr_iget(struct inode *base_vi, ATTR_TYPE type,
 228                ntfschar *name, u32 name_len)
 229{
 230        struct inode *vi;
 231        int err;
 232        ntfs_attr na;
 233
 234        /* Make sure no one calls ntfs_attr_iget() for indices. */
 235        BUG_ON(type == AT_INDEX_ALLOCATION);
 236
 237        na.mft_no = base_vi->i_ino;
 238        na.type = type;
 239        na.name = name;
 240        na.name_len = name_len;
 241
 242        vi = iget5_locked(base_vi->i_sb, na.mft_no, (test_t)ntfs_test_inode,
 243                        (set_t)ntfs_init_locked_inode, &na);
 244        if (unlikely(!vi))
 245                return ERR_PTR(-ENOMEM);
 246
 247        err = 0;
 248
 249        /* If this is a freshly allocated inode, need to read it now. */
 250        if (vi->i_state & I_NEW) {
 251                err = ntfs_read_locked_attr_inode(base_vi, vi);
 252                unlock_new_inode(vi);
 253        }
 254        /*
 255         * There is no point in keeping bad attribute inodes around. This also
 256         * simplifies things in that we never need to check for bad attribute
 257         * inodes elsewhere.
 258         */
 259        if (unlikely(err)) {
 260                iput(vi);
 261                vi = ERR_PTR(err);
 262        }
 263        return vi;
 264}
 265
 266/**
 267 * ntfs_index_iget - obtain a struct inode corresponding to an index
 268 * @base_vi:    vfs base inode containing the index related attributes
 269 * @name:       Unicode name of the index
 270 * @name_len:   length of @name in Unicode characters
 271 *
 272 * Obtain the (fake) struct inode corresponding to the index specified by @name
 273 * and @name_len, which is present in the base mft record specified by the vfs
 274 * inode @base_vi.
 275 *
 276 * If the index inode is in the cache, it is just returned with an increased
 277 * reference count.  Otherwise, a new struct inode is allocated and
 278 * initialized, and finally ntfs_read_locked_index_inode() is called to read
 279 * the index related attributes and fill in the inode structure.
 280 *
 281 * Return the struct inode of the index inode on success. Check the return
 282 * value with IS_ERR() and if true, the function failed and the error code is
 283 * obtained from PTR_ERR().
 284 */
 285struct inode *ntfs_index_iget(struct inode *base_vi, ntfschar *name,
 286                u32 name_len)
 287{
 288        struct inode *vi;
 289        int err;
 290        ntfs_attr na;
 291
 292        na.mft_no = base_vi->i_ino;
 293        na.type = AT_INDEX_ALLOCATION;
 294        na.name = name;
 295        na.name_len = name_len;
 296
 297        vi = iget5_locked(base_vi->i_sb, na.mft_no, (test_t)ntfs_test_inode,
 298                        (set_t)ntfs_init_locked_inode, &na);
 299        if (unlikely(!vi))
 300                return ERR_PTR(-ENOMEM);
 301
 302        err = 0;
 303
 304        /* If this is a freshly allocated inode, need to read it now. */
 305        if (vi->i_state & I_NEW) {
 306                err = ntfs_read_locked_index_inode(base_vi, vi);
 307                unlock_new_inode(vi);
 308        }
 309        /*
 310         * There is no point in keeping bad index inodes around.  This also
 311         * simplifies things in that we never need to check for bad index
 312         * inodes elsewhere.
 313         */
 314        if (unlikely(err)) {
 315                iput(vi);
 316                vi = ERR_PTR(err);
 317        }
 318        return vi;
 319}
 320
 321struct inode *ntfs_alloc_big_inode(struct super_block *sb)
 322{
 323        ntfs_inode *ni;
 324
 325        ntfs_debug("Entering.");
 326        ni = kmem_cache_alloc(ntfs_big_inode_cache, GFP_NOFS);
 327        if (likely(ni != NULL)) {
 328                ni->state = 0;
 329                return VFS_I(ni);
 330        }
 331        ntfs_error(sb, "Allocation of NTFS big inode structure failed.");
 332        return NULL;
 333}
 334
 335static void ntfs_i_callback(struct rcu_head *head)
 336{
 337        struct inode *inode = container_of(head, struct inode, i_rcu);
 338        kmem_cache_free(ntfs_big_inode_cache, NTFS_I(inode));
 339}
 340
 341void ntfs_destroy_big_inode(struct inode *inode)
 342{
 343        ntfs_inode *ni = NTFS_I(inode);
 344
 345        ntfs_debug("Entering.");
 346        BUG_ON(ni->page);
 347        if (!atomic_dec_and_test(&ni->count))
 348                BUG();
 349        call_rcu(&inode->i_rcu, ntfs_i_callback);
 350}
 351
 352static inline ntfs_inode *ntfs_alloc_extent_inode(void)
 353{
 354        ntfs_inode *ni;
 355
 356        ntfs_debug("Entering.");
 357        ni = kmem_cache_alloc(ntfs_inode_cache, GFP_NOFS);
 358        if (likely(ni != NULL)) {
 359                ni->state = 0;
 360                return ni;
 361        }
 362        ntfs_error(NULL, "Allocation of NTFS inode structure failed.");
 363        return NULL;
 364}
 365
 366static void ntfs_destroy_extent_inode(ntfs_inode *ni)
 367{
 368        ntfs_debug("Entering.");
 369        BUG_ON(ni->page);
 370        if (!atomic_dec_and_test(&ni->count))
 371                BUG();
 372        kmem_cache_free(ntfs_inode_cache, ni);
 373}
 374
 375/*
 376 * The attribute runlist lock has separate locking rules from the
 377 * normal runlist lock, so split the two lock-classes:
 378 */
 379static struct lock_class_key attr_list_rl_lock_class;
 380
 381/**
 382 * __ntfs_init_inode - initialize ntfs specific part of an inode
 383 * @sb:         super block of mounted volume
 384 * @ni:         freshly allocated ntfs inode which to initialize
 385 *
 386 * Initialize an ntfs inode to defaults.
 387 *
 388 * NOTE: ni->mft_no, ni->state, ni->type, ni->name, and ni->name_len are left
 389 * untouched. Make sure to initialize them elsewhere.
 390 *
 391 * Return zero on success and -ENOMEM on error.
 392 */
 393void __ntfs_init_inode(struct super_block *sb, ntfs_inode *ni)
 394{
 395        ntfs_debug("Entering.");
 396        rwlock_init(&ni->size_lock);
 397        ni->initialized_size = ni->allocated_size = 0;
 398        ni->seq_no = 0;
 399        atomic_set(&ni->count, 1);
 400        ni->vol = NTFS_SB(sb);
 401        ntfs_init_runlist(&ni->runlist);
 402        mutex_init(&ni->mrec_lock);
 403        ni->page = NULL;
 404        ni->page_ofs = 0;
 405        ni->attr_list_size = 0;
 406        ni->attr_list = NULL;
 407        ntfs_init_runlist(&ni->attr_list_rl);
 408        lockdep_set_class(&ni->attr_list_rl.lock,
 409                                &attr_list_rl_lock_class);
 410        ni->itype.index.block_size = 0;
 411        ni->itype.index.vcn_size = 0;
 412        ni->itype.index.collation_rule = 0;
 413        ni->itype.index.block_size_bits = 0;
 414        ni->itype.index.vcn_size_bits = 0;
 415        mutex_init(&ni->extent_lock);
 416        ni->nr_extents = 0;
 417        ni->ext.base_ntfs_ino = NULL;
 418}
 419
 420/*
 421 * Extent inodes get MFT-mapped in a nested way, while the base inode
 422 * is still mapped. Teach this nesting to the lock validator by creating
 423 * a separate class for nested inode's mrec_lock's:
 424 */
 425static struct lock_class_key extent_inode_mrec_lock_key;
 426
 427inline ntfs_inode *ntfs_new_extent_inode(struct super_block *sb,
 428                unsigned long mft_no)
 429{
 430        ntfs_inode *ni = ntfs_alloc_extent_inode();
 431
 432        ntfs_debug("Entering.");
 433        if (likely(ni != NULL)) {
 434                __ntfs_init_inode(sb, ni);
 435                lockdep_set_class(&ni->mrec_lock, &extent_inode_mrec_lock_key);
 436                ni->mft_no = mft_no;
 437                ni->type = AT_UNUSED;
 438                ni->name = NULL;
 439                ni->name_len = 0;
 440        }
 441        return ni;
 442}
 443
 444/**
 445 * ntfs_is_extended_system_file - check if a file is in the $Extend directory
 446 * @ctx:        initialized attribute search context
 447 *
 448 * Search all file name attributes in the inode described by the attribute
 449 * search context @ctx and check if any of the names are in the $Extend system
 450 * directory.
 451 *
 452 * Return values:
 453 *         1: file is in $Extend directory
 454 *         0: file is not in $Extend directory
 455 *    -errno: failed to determine if the file is in the $Extend directory
 456 */
 457static int ntfs_is_extended_system_file(ntfs_attr_search_ctx *ctx)
 458{
 459        int nr_links, err;
 460
 461        /* Restart search. */
 462        ntfs_attr_reinit_search_ctx(ctx);
 463
 464        /* Get number of hard links. */
 465        nr_links = le16_to_cpu(ctx->mrec->link_count);
 466
 467        /* Loop through all hard links. */
 468        while (!(err = ntfs_attr_lookup(AT_FILE_NAME, NULL, 0, 0, 0, NULL, 0,
 469                        ctx))) {
 470                FILE_NAME_ATTR *file_name_attr;
 471                ATTR_RECORD *attr = ctx->attr;
 472                u8 *p, *p2;
 473
 474                nr_links--;
 475                /*
 476                 * Maximum sanity checking as we are called on an inode that
 477                 * we suspect might be corrupt.
 478                 */
 479                p = (u8*)attr + le32_to_cpu(attr->length);
 480                if (p < (u8*)ctx->mrec || (u8*)p > (u8*)ctx->mrec +
 481                                le32_to_cpu(ctx->mrec->bytes_in_use)) {
 482err_corrupt_attr:
 483                        ntfs_error(ctx->ntfs_ino->vol->sb, "Corrupt file name "
 484                                        "attribute. You should run chkdsk.");
 485                        return -EIO;
 486                }
 487                if (attr->non_resident) {
 488                        ntfs_error(ctx->ntfs_ino->vol->sb, "Non-resident file "
 489                                        "name. You should run chkdsk.");
 490                        return -EIO;
 491                }
 492                if (attr->flags) {
 493                        ntfs_error(ctx->ntfs_ino->vol->sb, "File name with "
 494                                        "invalid flags. You should run "
 495                                        "chkdsk.");
 496                        return -EIO;
 497                }
 498                if (!(attr->data.resident.flags & RESIDENT_ATTR_IS_INDEXED)) {
 499                        ntfs_error(ctx->ntfs_ino->vol->sb, "Unindexed file "
 500                                        "name. You should run chkdsk.");
 501                        return -EIO;
 502                }
 503                file_name_attr = (FILE_NAME_ATTR*)((u8*)attr +
 504                                le16_to_cpu(attr->data.resident.value_offset));
 505                p2 = (u8*)attr + le32_to_cpu(attr->data.resident.value_length);
 506                if (p2 < (u8*)attr || p2 > p)
 507                        goto err_corrupt_attr;
 508                /* This attribute is ok, but is it in the $Extend directory? */
 509                if (MREF_LE(file_name_attr->parent_directory) == FILE_Extend)
 510                        return 1;       /* YES, it's an extended system file. */
 511        }
 512        if (unlikely(err != -ENOENT))
 513                return err;
 514        if (unlikely(nr_links)) {
 515                ntfs_error(ctx->ntfs_ino->vol->sb, "Inode hard link count "
 516                                "doesn't match number of name attributes. You "
 517                                "should run chkdsk.");
 518                return -EIO;
 519        }
 520        return 0;       /* NO, it is not an extended system file. */
 521}
 522
 523/**
 524 * ntfs_read_locked_inode - read an inode from its device
 525 * @vi:         inode to read
 526 *
 527 * ntfs_read_locked_inode() is called from ntfs_iget() to read the inode
 528 * described by @vi into memory from the device.
 529 *
 530 * The only fields in @vi that we need to/can look at when the function is
 531 * called are i_sb, pointing to the mounted device's super block, and i_ino,
 532 * the number of the inode to load.
 533 *
 534 * ntfs_read_locked_inode() maps, pins and locks the mft record number i_ino
 535 * for reading and sets up the necessary @vi fields as well as initializing
 536 * the ntfs inode.
 537 *
 538 * Q: What locks are held when the function is called?
 539 * A: i_state has I_NEW set, hence the inode is locked, also
 540 *    i_count is set to 1, so it is not going to go away
 541 *    i_flags is set to 0 and we have no business touching it.  Only an ioctl()
 542 *    is allowed to write to them. We should of course be honouring them but
 543 *    we need to do that using the IS_* macros defined in include/linux/fs.h.
 544 *    In any case ntfs_read_locked_inode() has nothing to do with i_flags.
 545 *
 546 * Return 0 on success and -errno on error.  In the error case, the inode will
 547 * have had make_bad_inode() executed on it.
 548 */
 549static int ntfs_read_locked_inode(struct inode *vi)
 550{
 551        ntfs_volume *vol = NTFS_SB(vi->i_sb);
 552        ntfs_inode *ni;
 553        struct inode *bvi;
 554        MFT_RECORD *m;
 555        ATTR_RECORD *a;
 556        STANDARD_INFORMATION *si;
 557        ntfs_attr_search_ctx *ctx;
 558        int err = 0;
 559
 560        ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
 561
 562        /* Setup the generic vfs inode parts now. */
 563
 564        /*
 565         * This is for checking whether an inode has changed w.r.t. a file so
 566         * that the file can be updated if necessary (compare with f_version).
 567         */
 568        vi->i_version = 1;
 569
 570        vi->i_uid = vol->uid;
 571        vi->i_gid = vol->gid;
 572        vi->i_mode = 0;
 573
 574        /*
 575         * Initialize the ntfs specific part of @vi special casing
 576         * FILE_MFT which we need to do at mount time.
 577         */
 578        if (vi->i_ino != FILE_MFT)
 579                ntfs_init_big_inode(vi);
 580        ni = NTFS_I(vi);
 581
 582        m = map_mft_record(ni);
 583        if (IS_ERR(m)) {
 584                err = PTR_ERR(m);
 585                goto err_out;
 586        }
 587        ctx = ntfs_attr_get_search_ctx(ni, m);
 588        if (!ctx) {
 589                err = -ENOMEM;
 590                goto unm_err_out;
 591        }
 592
 593        if (!(m->flags & MFT_RECORD_IN_USE)) {
 594                ntfs_error(vi->i_sb, "Inode is not in use!");
 595                goto unm_err_out;
 596        }
 597        if (m->base_mft_record) {
 598                ntfs_error(vi->i_sb, "Inode is an extent inode!");
 599                goto unm_err_out;
 600        }
 601
 602        /* Transfer information from mft record into vfs and ntfs inodes. */
 603        vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
 604
 605        /*
 606         * FIXME: Keep in mind that link_count is two for files which have both
 607         * a long file name and a short file name as separate entries, so if
 608         * we are hiding short file names this will be too high. Either we need
 609         * to account for the short file names by subtracting them or we need
 610         * to make sure we delete files even though i_nlink is not zero which
 611         * might be tricky due to vfs interactions. Need to think about this
 612         * some more when implementing the unlink command.
 613         */
 614        set_nlink(vi, le16_to_cpu(m->link_count));
 615        /*
 616         * FIXME: Reparse points can have the directory bit set even though
 617         * they would be S_IFLNK. Need to deal with this further below when we
 618         * implement reparse points / symbolic links but it will do for now.
 619         * Also if not a directory, it could be something else, rather than
 620         * a regular file. But again, will do for now.
 621         */
 622        /* Everyone gets all permissions. */
 623        vi->i_mode |= S_IRWXUGO;
 624        /* If read-only, no one gets write permissions. */
 625        if (IS_RDONLY(vi))
 626                vi->i_mode &= ~S_IWUGO;
 627        if (m->flags & MFT_RECORD_IS_DIRECTORY) {
 628                vi->i_mode |= S_IFDIR;
 629                /*
 630                 * Apply the directory permissions mask set in the mount
 631                 * options.
 632                 */
 633                vi->i_mode &= ~vol->dmask;
 634                /* Things break without this kludge! */
 635                if (vi->i_nlink > 1)
 636                        set_nlink(vi, 1);
 637        } else {
 638                vi->i_mode |= S_IFREG;
 639                /* Apply the file permissions mask set in the mount options. */
 640                vi->i_mode &= ~vol->fmask;
 641        }
 642        /*
 643         * Find the standard information attribute in the mft record. At this
 644         * stage we haven't setup the attribute list stuff yet, so this could
 645         * in fact fail if the standard information is in an extent record, but
 646         * I don't think this actually ever happens.
 647         */
 648        err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0, 0, 0, NULL, 0,
 649                        ctx);
 650        if (unlikely(err)) {
 651                if (err == -ENOENT) {
 652                        /*
 653                         * TODO: We should be performing a hot fix here (if the
 654                         * recover mount option is set) by creating a new
 655                         * attribute.
 656                         */
 657                        ntfs_error(vi->i_sb, "$STANDARD_INFORMATION attribute "
 658                                        "is missing.");
 659                }
 660                goto unm_err_out;
 661        }
 662        a = ctx->attr;
 663        /* Get the standard information attribute value. */
 664        si = (STANDARD_INFORMATION*)((u8*)a +
 665                        le16_to_cpu(a->data.resident.value_offset));
 666
 667        /* Transfer information from the standard information into vi. */
 668        /*
 669         * Note: The i_?times do not quite map perfectly onto the NTFS times,
 670         * but they are close enough, and in the end it doesn't really matter
 671         * that much...
 672         */
 673        /*
 674         * mtime is the last change of the data within the file. Not changed
 675         * when only metadata is changed, e.g. a rename doesn't affect mtime.
 676         */
 677        vi->i_mtime = ntfs2utc(si->last_data_change_time);
 678        /*
 679         * ctime is the last change of the metadata of the file. This obviously
 680         * always changes, when mtime is changed. ctime can be changed on its
 681         * own, mtime is then not changed, e.g. when a file is renamed.
 682         */
 683        vi->i_ctime = ntfs2utc(si->last_mft_change_time);
 684        /*
 685         * Last access to the data within the file. Not changed during a rename
 686         * for example but changed whenever the file is written to.
 687         */
 688        vi->i_atime = ntfs2utc(si->last_access_time);
 689
 690        /* Find the attribute list attribute if present. */
 691        ntfs_attr_reinit_search_ctx(ctx);
 692        err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
 693        if (err) {
 694                if (unlikely(err != -ENOENT)) {
 695                        ntfs_error(vi->i_sb, "Failed to lookup attribute list "
 696                                        "attribute.");
 697                        goto unm_err_out;
 698                }
 699        } else /* if (!err) */ {
 700                if (vi->i_ino == FILE_MFT)
 701                        goto skip_attr_list_load;
 702                ntfs_debug("Attribute list found in inode 0x%lx.", vi->i_ino);
 703                NInoSetAttrList(ni);
 704                a = ctx->attr;
 705                if (a->flags & ATTR_COMPRESSION_MASK) {
 706                        ntfs_error(vi->i_sb, "Attribute list attribute is "
 707                                        "compressed.");
 708                        goto unm_err_out;
 709                }
 710                if (a->flags & ATTR_IS_ENCRYPTED ||
 711                                a->flags & ATTR_IS_SPARSE) {
 712                        if (a->non_resident) {
 713                                ntfs_error(vi->i_sb, "Non-resident attribute "
 714                                                "list attribute is encrypted/"
 715                                                "sparse.");
 716                                goto unm_err_out;
 717                        }
 718                        ntfs_warning(vi->i_sb, "Resident attribute list "
 719                                        "attribute in inode 0x%lx is marked "
 720                                        "encrypted/sparse which is not true.  "
 721                                        "However, Windows allows this and "
 722                                        "chkdsk does not detect or correct it "
 723                                        "so we will just ignore the invalid "
 724                                        "flags and pretend they are not set.",
 725                                        vi->i_ino);
 726                }
 727                /* Now allocate memory for the attribute list. */
 728                ni->attr_list_size = (u32)ntfs_attr_size(a);
 729                ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
 730                if (!ni->attr_list) {
 731                        ntfs_error(vi->i_sb, "Not enough memory to allocate "
 732                                        "buffer for attribute list.");
 733                        err = -ENOMEM;
 734                        goto unm_err_out;
 735                }
 736                if (a->non_resident) {
 737                        NInoSetAttrListNonResident(ni);
 738                        if (a->data.non_resident.lowest_vcn) {
 739                                ntfs_error(vi->i_sb, "Attribute list has non "
 740                                                "zero lowest_vcn.");
 741                                goto unm_err_out;
 742                        }
 743                        /*
 744                         * Setup the runlist. No need for locking as we have
 745                         * exclusive access to the inode at this time.
 746                         */
 747                        ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
 748                                        a, NULL);
 749                        if (IS_ERR(ni->attr_list_rl.rl)) {
 750                                err = PTR_ERR(ni->attr_list_rl.rl);
 751                                ni->attr_list_rl.rl = NULL;
 752                                ntfs_error(vi->i_sb, "Mapping pairs "
 753                                                "decompression failed.");
 754                                goto unm_err_out;
 755                        }
 756                        /* Now load the attribute list. */
 757                        if ((err = load_attribute_list(vol, &ni->attr_list_rl,
 758                                        ni->attr_list, ni->attr_list_size,
 759                                        sle64_to_cpu(a->data.non_resident.
 760                                        initialized_size)))) {
 761                                ntfs_error(vi->i_sb, "Failed to load "
 762                                                "attribute list attribute.");
 763                                goto unm_err_out;
 764                        }
 765                } else /* if (!a->non_resident) */ {
 766                        if ((u8*)a + le16_to_cpu(a->data.resident.value_offset)
 767                                        + le32_to_cpu(
 768                                        a->data.resident.value_length) >
 769                                        (u8*)ctx->mrec + vol->mft_record_size) {
 770                                ntfs_error(vi->i_sb, "Corrupt attribute list "
 771                                                "in inode.");
 772                                goto unm_err_out;
 773                        }
 774                        /* Now copy the attribute list. */
 775                        memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
 776                                        a->data.resident.value_offset),
 777                                        le32_to_cpu(
 778                                        a->data.resident.value_length));
 779                }
 780        }
 781skip_attr_list_load:
 782        /*
 783         * If an attribute list is present we now have the attribute list value
 784         * in ntfs_ino->attr_list and it is ntfs_ino->attr_list_size bytes.
 785         */
 786        if (S_ISDIR(vi->i_mode)) {
 787                loff_t bvi_size;
 788                ntfs_inode *bni;
 789                INDEX_ROOT *ir;
 790                u8 *ir_end, *index_end;
 791
 792                /* It is a directory, find index root attribute. */
 793                ntfs_attr_reinit_search_ctx(ctx);
 794                err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE,
 795                                0, NULL, 0, ctx);
 796                if (unlikely(err)) {
 797                        if (err == -ENOENT) {
 798                                // FIXME: File is corrupt! Hot-fix with empty
 799                                // index root attribute if recovery option is
 800                                // set.
 801                                ntfs_error(vi->i_sb, "$INDEX_ROOT attribute "
 802                                                "is missing.");
 803                        }
 804                        goto unm_err_out;
 805                }
 806                a = ctx->attr;
 807                /* Set up the state. */
 808                if (unlikely(a->non_resident)) {
 809                        ntfs_error(vol->sb, "$INDEX_ROOT attribute is not "
 810                                        "resident.");
 811                        goto unm_err_out;
 812                }
 813                /* Ensure the attribute name is placed before the value. */
 814                if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
 815                                le16_to_cpu(a->data.resident.value_offset)))) {
 816                        ntfs_error(vol->sb, "$INDEX_ROOT attribute name is "
 817                                        "placed after the attribute value.");
 818                        goto unm_err_out;
 819                }
 820                /*
 821                 * Compressed/encrypted index root just means that the newly
 822                 * created files in that directory should be created compressed/
 823                 * encrypted. However index root cannot be both compressed and
 824                 * encrypted.
 825                 */
 826                if (a->flags & ATTR_COMPRESSION_MASK)
 827                        NInoSetCompressed(ni);
 828                if (a->flags & ATTR_IS_ENCRYPTED) {
 829                        if (a->flags & ATTR_COMPRESSION_MASK) {
 830                                ntfs_error(vi->i_sb, "Found encrypted and "
 831                                                "compressed attribute.");
 832                                goto unm_err_out;
 833                        }
 834                        NInoSetEncrypted(ni);
 835                }
 836                if (a->flags & ATTR_IS_SPARSE)
 837                        NInoSetSparse(ni);
 838                ir = (INDEX_ROOT*)((u8*)a +
 839                                le16_to_cpu(a->data.resident.value_offset));
 840                ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
 841                if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
 842                        ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
 843                                        "corrupt.");
 844                        goto unm_err_out;
 845                }
 846                index_end = (u8*)&ir->index +
 847                                le32_to_cpu(ir->index.index_length);
 848                if (index_end > ir_end) {
 849                        ntfs_error(vi->i_sb, "Directory index is corrupt.");
 850                        goto unm_err_out;
 851                }
 852                if (ir->type != AT_FILE_NAME) {
 853                        ntfs_error(vi->i_sb, "Indexed attribute is not "
 854                                        "$FILE_NAME.");
 855                        goto unm_err_out;
 856                }
 857                if (ir->collation_rule != COLLATION_FILE_NAME) {
 858                        ntfs_error(vi->i_sb, "Index collation rule is not "
 859                                        "COLLATION_FILE_NAME.");
 860                        goto unm_err_out;
 861                }
 862                ni->itype.index.collation_rule = ir->collation_rule;
 863                ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
 864                if (ni->itype.index.block_size &
 865                                (ni->itype.index.block_size - 1)) {
 866                        ntfs_error(vi->i_sb, "Index block size (%u) is not a "
 867                                        "power of two.",
 868                                        ni->itype.index.block_size);
 869                        goto unm_err_out;
 870                }
 871                if (ni->itype.index.block_size > PAGE_CACHE_SIZE) {
 872                        ntfs_error(vi->i_sb, "Index block size (%u) > "
 873                                        "PAGE_CACHE_SIZE (%ld) is not "
 874                                        "supported.  Sorry.",
 875                                        ni->itype.index.block_size,
 876                                        PAGE_CACHE_SIZE);
 877                        err = -EOPNOTSUPP;
 878                        goto unm_err_out;
 879                }
 880                if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
 881                        ntfs_error(vi->i_sb, "Index block size (%u) < "
 882                                        "NTFS_BLOCK_SIZE (%i) is not "
 883                                        "supported.  Sorry.",
 884                                        ni->itype.index.block_size,
 885                                        NTFS_BLOCK_SIZE);
 886                        err = -EOPNOTSUPP;
 887                        goto unm_err_out;
 888                }
 889                ni->itype.index.block_size_bits =
 890                                ffs(ni->itype.index.block_size) - 1;
 891                /* Determine the size of a vcn in the directory index. */
 892                if (vol->cluster_size <= ni->itype.index.block_size) {
 893                        ni->itype.index.vcn_size = vol->cluster_size;
 894                        ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
 895                } else {
 896                        ni->itype.index.vcn_size = vol->sector_size;
 897                        ni->itype.index.vcn_size_bits = vol->sector_size_bits;
 898                }
 899
 900                /* Setup the index allocation attribute, even if not present. */
 901                NInoSetMstProtected(ni);
 902                ni->type = AT_INDEX_ALLOCATION;
 903                ni->name = I30;
 904                ni->name_len = 4;
 905
 906                if (!(ir->index.flags & LARGE_INDEX)) {
 907                        /* No index allocation. */
 908                        vi->i_size = ni->initialized_size =
 909                                        ni->allocated_size = 0;
 910                        /* We are done with the mft record, so we release it. */
 911                        ntfs_attr_put_search_ctx(ctx);
 912                        unmap_mft_record(ni);
 913                        m = NULL;
 914                        ctx = NULL;
 915                        goto skip_large_dir_stuff;
 916                } /* LARGE_INDEX: Index allocation present. Setup state. */
 917                NInoSetIndexAllocPresent(ni);
 918                /* Find index allocation attribute. */
 919                ntfs_attr_reinit_search_ctx(ctx);
 920                err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, I30, 4,
 921                                CASE_SENSITIVE, 0, NULL, 0, ctx);
 922                if (unlikely(err)) {
 923                        if (err == -ENOENT)
 924                                ntfs_error(vi->i_sb, "$INDEX_ALLOCATION "
 925                                                "attribute is not present but "
 926                                                "$INDEX_ROOT indicated it is.");
 927                        else
 928                                ntfs_error(vi->i_sb, "Failed to lookup "
 929                                                "$INDEX_ALLOCATION "
 930                                                "attribute.");
 931                        goto unm_err_out;
 932                }
 933                a = ctx->attr;
 934                if (!a->non_resident) {
 935                        ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 936                                        "is resident.");
 937                        goto unm_err_out;
 938                }
 939                /*
 940                 * Ensure the attribute name is placed before the mapping pairs
 941                 * array.
 942                 */
 943                if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
 944                                le16_to_cpu(
 945                                a->data.non_resident.mapping_pairs_offset)))) {
 946                        ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name "
 947                                        "is placed after the mapping pairs "
 948                                        "array.");
 949                        goto unm_err_out;
 950                }
 951                if (a->flags & ATTR_IS_ENCRYPTED) {
 952                        ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 953                                        "is encrypted.");
 954                        goto unm_err_out;
 955                }
 956                if (a->flags & ATTR_IS_SPARSE) {
 957                        ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 958                                        "is sparse.");
 959                        goto unm_err_out;
 960                }
 961                if (a->flags & ATTR_COMPRESSION_MASK) {
 962                        ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
 963                                        "is compressed.");
 964                        goto unm_err_out;
 965                }
 966                if (a->data.non_resident.lowest_vcn) {
 967                        ntfs_error(vi->i_sb, "First extent of "
 968                                        "$INDEX_ALLOCATION attribute has non "
 969                                        "zero lowest_vcn.");
 970                        goto unm_err_out;
 971                }
 972                vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
 973                ni->initialized_size = sle64_to_cpu(
 974                                a->data.non_resident.initialized_size);
 975                ni->allocated_size = sle64_to_cpu(
 976                                a->data.non_resident.allocated_size);
 977                /*
 978                 * We are done with the mft record, so we release it. Otherwise
 979                 * we would deadlock in ntfs_attr_iget().
 980                 */
 981                ntfs_attr_put_search_ctx(ctx);
 982                unmap_mft_record(ni);
 983                m = NULL;
 984                ctx = NULL;
 985                /* Get the index bitmap attribute inode. */
 986                bvi = ntfs_attr_iget(vi, AT_BITMAP, I30, 4);
 987                if (IS_ERR(bvi)) {
 988                        ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
 989                        err = PTR_ERR(bvi);
 990                        goto unm_err_out;
 991                }
 992                bni = NTFS_I(bvi);
 993                if (NInoCompressed(bni) || NInoEncrypted(bni) ||
 994                                NInoSparse(bni)) {
 995                        ntfs_error(vi->i_sb, "$BITMAP attribute is compressed "
 996                                        "and/or encrypted and/or sparse.");
 997                        goto iput_unm_err_out;
 998                }
 999                /* Consistency check bitmap size vs. index allocation size. */
1000                bvi_size = i_size_read(bvi);
1001                if ((bvi_size << 3) < (vi->i_size >>
1002                                ni->itype.index.block_size_bits)) {
1003                        ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) "
1004                                        "for index allocation (0x%llx).",
1005                                        bvi_size << 3, vi->i_size);
1006                        goto iput_unm_err_out;
1007                }
1008                /* No longer need the bitmap attribute inode. */
1009                iput(bvi);
1010skip_large_dir_stuff:
1011                /* Setup the operations for this inode. */
1012                vi->i_op = &ntfs_dir_inode_ops;
1013                vi->i_fop = &ntfs_dir_ops;
1014        } else {
1015                /* It is a file. */
1016                ntfs_attr_reinit_search_ctx(ctx);
1017
1018                /* Setup the data attribute, even if not present. */
1019                ni->type = AT_DATA;
1020                ni->name = NULL;
1021                ni->name_len = 0;
1022
1023                /* Find first extent of the unnamed data attribute. */
1024                err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, 0, NULL, 0, ctx);
1025                if (unlikely(err)) {
1026                        vi->i_size = ni->initialized_size =
1027                                        ni->allocated_size = 0;
1028                        if (err != -ENOENT) {
1029                                ntfs_error(vi->i_sb, "Failed to lookup $DATA "
1030                                                "attribute.");
1031                                goto unm_err_out;
1032                        }
1033                        /*
1034                         * FILE_Secure does not have an unnamed $DATA
1035                         * attribute, so we special case it here.
1036                         */
1037                        if (vi->i_ino == FILE_Secure)
1038                                goto no_data_attr_special_case;
1039                        /*
1040                         * Most if not all the system files in the $Extend
1041                         * system directory do not have unnamed data
1042                         * attributes so we need to check if the parent
1043                         * directory of the file is FILE_Extend and if it is
1044                         * ignore this error. To do this we need to get the
1045                         * name of this inode from the mft record as the name
1046                         * contains the back reference to the parent directory.
1047                         */
1048                        if (ntfs_is_extended_system_file(ctx) > 0)
1049                                goto no_data_attr_special_case;
1050                        // FIXME: File is corrupt! Hot-fix with empty data
1051                        // attribute if recovery option is set.
1052                        ntfs_error(vi->i_sb, "$DATA attribute is missing.");
1053                        goto unm_err_out;
1054                }
1055                a = ctx->attr;
1056                /* Setup the state. */
1057                if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1058                        if (a->flags & ATTR_COMPRESSION_MASK) {
1059                                NInoSetCompressed(ni);
1060                                if (vol->cluster_size > 4096) {
1061                                        ntfs_error(vi->i_sb, "Found "
1062                                                        "compressed data but "
1063                                                        "compression is "
1064                                                        "disabled due to "
1065                                                        "cluster size (%i) > "
1066                                                        "4kiB.",
1067                                                        vol->cluster_size);
1068                                        goto unm_err_out;
1069                                }
1070                                if ((a->flags & ATTR_COMPRESSION_MASK)
1071                                                != ATTR_IS_COMPRESSED) {
1072                                        ntfs_error(vi->i_sb, "Found unknown "
1073                                                        "compression method "
1074                                                        "or corrupt file.");
1075                                        goto unm_err_out;
1076                                }
1077                        }
1078                        if (a->flags & ATTR_IS_SPARSE)
1079                                NInoSetSparse(ni);
1080                }
1081                if (a->flags & ATTR_IS_ENCRYPTED) {
1082                        if (NInoCompressed(ni)) {
1083                                ntfs_error(vi->i_sb, "Found encrypted and "
1084                                                "compressed data.");
1085                                goto unm_err_out;
1086                        }
1087                        NInoSetEncrypted(ni);
1088                }
1089                if (a->non_resident) {
1090                        NInoSetNonResident(ni);
1091                        if (NInoCompressed(ni) || NInoSparse(ni)) {
1092                                if (NInoCompressed(ni) && a->data.non_resident.
1093                                                compression_unit != 4) {
1094                                        ntfs_error(vi->i_sb, "Found "
1095                                                        "non-standard "
1096                                                        "compression unit (%u "
1097                                                        "instead of 4).  "
1098                                                        "Cannot handle this.",
1099                                                        a->data.non_resident.
1100                                                        compression_unit);
1101                                        err = -EOPNOTSUPP;
1102                                        goto unm_err_out;
1103                                }
1104                                if (a->data.non_resident.compression_unit) {
1105                                        ni->itype.compressed.block_size = 1U <<
1106                                                        (a->data.non_resident.
1107                                                        compression_unit +
1108                                                        vol->cluster_size_bits);
1109                                        ni->itype.compressed.block_size_bits =
1110                                                        ffs(ni->itype.
1111                                                        compressed.
1112                                                        block_size) - 1;
1113                                        ni->itype.compressed.block_clusters =
1114                                                        1U << a->data.
1115                                                        non_resident.
1116                                                        compression_unit;
1117                                } else {
1118                                        ni->itype.compressed.block_size = 0;
1119                                        ni->itype.compressed.block_size_bits =
1120                                                        0;
1121                                        ni->itype.compressed.block_clusters =
1122                                                        0;
1123                                }
1124                                ni->itype.compressed.size = sle64_to_cpu(
1125                                                a->data.non_resident.
1126                                                compressed_size);
1127                        }
1128                        if (a->data.non_resident.lowest_vcn) {
1129                                ntfs_error(vi->i_sb, "First extent of $DATA "
1130                                                "attribute has non zero "
1131                                                "lowest_vcn.");
1132                                goto unm_err_out;
1133                        }
1134                        vi->i_size = sle64_to_cpu(
1135                                        a->data.non_resident.data_size);
1136                        ni->initialized_size = sle64_to_cpu(
1137                                        a->data.non_resident.initialized_size);
1138                        ni->allocated_size = sle64_to_cpu(
1139                                        a->data.non_resident.allocated_size);
1140                } else { /* Resident attribute. */
1141                        vi->i_size = ni->initialized_size = le32_to_cpu(
1142                                        a->data.resident.value_length);
1143                        ni->allocated_size = le32_to_cpu(a->length) -
1144                                        le16_to_cpu(
1145                                        a->data.resident.value_offset);
1146                        if (vi->i_size > ni->allocated_size) {
1147                                ntfs_error(vi->i_sb, "Resident data attribute "
1148                                                "is corrupt (size exceeds "
1149                                                "allocation).");
1150                                goto unm_err_out;
1151                        }
1152                }
1153no_data_attr_special_case:
1154                /* We are done with the mft record, so we release it. */
1155                ntfs_attr_put_search_ctx(ctx);
1156                unmap_mft_record(ni);
1157                m = NULL;
1158                ctx = NULL;
1159                /* Setup the operations for this inode. */
1160                vi->i_op = &ntfs_file_inode_ops;
1161                vi->i_fop = &ntfs_file_ops;
1162        }
1163        if (NInoMstProtected(ni))
1164                vi->i_mapping->a_ops = &ntfs_mst_aops;
1165        else
1166                vi->i_mapping->a_ops = &ntfs_aops;
1167        /*
1168         * The number of 512-byte blocks used on disk (for stat). This is in so
1169         * far inaccurate as it doesn't account for any named streams or other
1170         * special non-resident attributes, but that is how Windows works, too,
1171         * so we are at least consistent with Windows, if not entirely
1172         * consistent with the Linux Way. Doing it the Linux Way would cause a
1173         * significant slowdown as it would involve iterating over all
1174         * attributes in the mft record and adding the allocated/compressed
1175         * sizes of all non-resident attributes present to give us the Linux
1176         * correct size that should go into i_blocks (after division by 512).
1177         */
1178        if (S_ISREG(vi->i_mode) && (NInoCompressed(ni) || NInoSparse(ni)))
1179                vi->i_blocks = ni->itype.compressed.size >> 9;
1180        else
1181                vi->i_blocks = ni->allocated_size >> 9;
1182        ntfs_debug("Done.");
1183        return 0;
1184iput_unm_err_out:
1185        iput(bvi);
1186unm_err_out:
1187        if (!err)
1188                err = -EIO;
1189        if (ctx)
1190                ntfs_attr_put_search_ctx(ctx);
1191        if (m)
1192                unmap_mft_record(ni);
1193err_out:
1194        ntfs_error(vol->sb, "Failed with error code %i.  Marking corrupt "
1195                        "inode 0x%lx as bad.  Run chkdsk.", err, vi->i_ino);
1196        make_bad_inode(vi);
1197        if (err != -EOPNOTSUPP && err != -ENOMEM)
1198                NVolSetErrors(vol);
1199        return err;
1200}
1201
1202/**
1203 * ntfs_read_locked_attr_inode - read an attribute inode from its base inode
1204 * @base_vi:    base inode
1205 * @vi:         attribute inode to read
1206 *
1207 * ntfs_read_locked_attr_inode() is called from ntfs_attr_iget() to read the
1208 * attribute inode described by @vi into memory from the base mft record
1209 * described by @base_ni.
1210 *
1211 * ntfs_read_locked_attr_inode() maps, pins and locks the base inode for
1212 * reading and looks up the attribute described by @vi before setting up the
1213 * necessary fields in @vi as well as initializing the ntfs inode.
1214 *
1215 * Q: What locks are held when the function is called?
1216 * A: i_state has I_NEW set, hence the inode is locked, also
1217 *    i_count is set to 1, so it is not going to go away
1218 *
1219 * Return 0 on success and -errno on error.  In the error case, the inode will
1220 * have had make_bad_inode() executed on it.
1221 *
1222 * Note this cannot be called for AT_INDEX_ALLOCATION.
1223 */
1224static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
1225{
1226        ntfs_volume *vol = NTFS_SB(vi->i_sb);
1227        ntfs_inode *ni, *base_ni;
1228        MFT_RECORD *m;
1229        ATTR_RECORD *a;
1230        ntfs_attr_search_ctx *ctx;
1231        int err = 0;
1232
1233        ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1234
1235        ntfs_init_big_inode(vi);
1236
1237        ni      = NTFS_I(vi);
1238        base_ni = NTFS_I(base_vi);
1239
1240        /* Just mirror the values from the base inode. */
1241        vi->i_version   = base_vi->i_version;
1242        vi->i_uid       = base_vi->i_uid;
1243        vi->i_gid       = base_vi->i_gid;
1244        set_nlink(vi, base_vi->i_nlink);
1245        vi->i_mtime     = base_vi->i_mtime;
1246        vi->i_ctime     = base_vi->i_ctime;
1247        vi->i_atime     = base_vi->i_atime;
1248        vi->i_generation = ni->seq_no = base_ni->seq_no;
1249
1250        /* Set inode type to zero but preserve permissions. */
1251        vi->i_mode      = base_vi->i_mode & ~S_IFMT;
1252
1253        m = map_mft_record(base_ni);
1254        if (IS_ERR(m)) {
1255                err = PTR_ERR(m);
1256                goto err_out;
1257        }
1258        ctx = ntfs_attr_get_search_ctx(base_ni, m);
1259        if (!ctx) {
1260                err = -ENOMEM;
1261                goto unm_err_out;
1262        }
1263        /* Find the attribute. */
1264        err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
1265                        CASE_SENSITIVE, 0, NULL, 0, ctx);
1266        if (unlikely(err))
1267                goto unm_err_out;
1268        a = ctx->attr;
1269        if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
1270                if (a->flags & ATTR_COMPRESSION_MASK) {
1271                        NInoSetCompressed(ni);
1272                        if ((ni->type != AT_DATA) || (ni->type == AT_DATA &&
1273                                        ni->name_len)) {
1274                                ntfs_error(vi->i_sb, "Found compressed "
1275                                                "non-data or named data "
1276                                                "attribute.  Please report "
1277                                                "you saw this message to "
1278                                                "linux-ntfs-dev@lists."
1279                                                "sourceforge.net");
1280                                goto unm_err_out;
1281                        }
1282                        if (vol->cluster_size > 4096) {
1283                                ntfs_error(vi->i_sb, "Found compressed "
1284                                                "attribute but compression is "
1285                                                "disabled due to cluster size "
1286                                                "(%i) > 4kiB.",
1287                                                vol->cluster_size);
1288                                goto unm_err_out;
1289                        }
1290                        if ((a->flags & ATTR_COMPRESSION_MASK) !=
1291                                        ATTR_IS_COMPRESSED) {
1292                                ntfs_error(vi->i_sb, "Found unknown "
1293                                                "compression method.");
1294                                goto unm_err_out;
1295                        }
1296                }
1297                /*
1298                 * The compressed/sparse flag set in an index root just means
1299                 * to compress all files.
1300                 */
1301                if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1302                        ntfs_error(vi->i_sb, "Found mst protected attribute "
1303                                        "but the attribute is %s.  Please "
1304                                        "report you saw this message to "
1305                                        "linux-ntfs-dev@lists.sourceforge.net",
1306                                        NInoCompressed(ni) ? "compressed" :
1307                                        "sparse");
1308                        goto unm_err_out;
1309                }
1310                if (a->flags & ATTR_IS_SPARSE)
1311                        NInoSetSparse(ni);
1312        }
1313        if (a->flags & ATTR_IS_ENCRYPTED) {
1314                if (NInoCompressed(ni)) {
1315                        ntfs_error(vi->i_sb, "Found encrypted and compressed "
1316                                        "data.");
1317                        goto unm_err_out;
1318                }
1319                /*
1320                 * The encryption flag set in an index root just means to
1321                 * encrypt all files.
1322                 */
1323                if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
1324                        ntfs_error(vi->i_sb, "Found mst protected attribute "
1325                                        "but the attribute is encrypted.  "
1326                                        "Please report you saw this message "
1327                                        "to linux-ntfs-dev@lists.sourceforge."
1328                                        "net");
1329                        goto unm_err_out;
1330                }
1331                if (ni->type != AT_DATA) {
1332                        ntfs_error(vi->i_sb, "Found encrypted non-data "
1333                                        "attribute.");
1334                        goto unm_err_out;
1335                }
1336                NInoSetEncrypted(ni);
1337        }
1338        if (!a->non_resident) {
1339                /* Ensure the attribute name is placed before the value. */
1340                if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1341                                le16_to_cpu(a->data.resident.value_offset)))) {
1342                        ntfs_error(vol->sb, "Attribute name is placed after "
1343                                        "the attribute value.");
1344                        goto unm_err_out;
1345                }
1346                if (NInoMstProtected(ni)) {
1347                        ntfs_error(vi->i_sb, "Found mst protected attribute "
1348                                        "but the attribute is resident.  "
1349                                        "Please report you saw this message to "
1350                                        "linux-ntfs-dev@lists.sourceforge.net");
1351                        goto unm_err_out;
1352                }
1353                vi->i_size = ni->initialized_size = le32_to_cpu(
1354                                a->data.resident.value_length);
1355                ni->allocated_size = le32_to_cpu(a->length) -
1356                                le16_to_cpu(a->data.resident.value_offset);
1357                if (vi->i_size > ni->allocated_size) {
1358                        ntfs_error(vi->i_sb, "Resident attribute is corrupt "
1359                                        "(size exceeds allocation).");
1360                        goto unm_err_out;
1361                }
1362        } else {
1363                NInoSetNonResident(ni);
1364                /*
1365                 * Ensure the attribute name is placed before the mapping pairs
1366                 * array.
1367                 */
1368                if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1369                                le16_to_cpu(
1370                                a->data.non_resident.mapping_pairs_offset)))) {
1371                        ntfs_error(vol->sb, "Attribute name is placed after "
1372                                        "the mapping pairs array.");
1373                        goto unm_err_out;
1374                }
1375                if (NInoCompressed(ni) || NInoSparse(ni)) {
1376                        if (NInoCompressed(ni) && a->data.non_resident.
1377                                        compression_unit != 4) {
1378                                ntfs_error(vi->i_sb, "Found non-standard "
1379                                                "compression unit (%u instead "
1380                                                "of 4).  Cannot handle this.",
1381                                                a->data.non_resident.
1382                                                compression_unit);
1383                                err = -EOPNOTSUPP;
1384                                goto unm_err_out;
1385                        }
1386                        if (a->data.non_resident.compression_unit) {
1387                                ni->itype.compressed.block_size = 1U <<
1388                                                (a->data.non_resident.
1389                                                compression_unit +
1390                                                vol->cluster_size_bits);
1391                                ni->itype.compressed.block_size_bits =
1392                                                ffs(ni->itype.compressed.
1393                                                block_size) - 1;
1394                                ni->itype.compressed.block_clusters = 1U <<
1395                                                a->data.non_resident.
1396                                                compression_unit;
1397                        } else {
1398                                ni->itype.compressed.block_size = 0;
1399                                ni->itype.compressed.block_size_bits = 0;
1400                                ni->itype.compressed.block_clusters = 0;
1401                        }
1402                        ni->itype.compressed.size = sle64_to_cpu(
1403                                        a->data.non_resident.compressed_size);
1404                }
1405                if (a->data.non_resident.lowest_vcn) {
1406                        ntfs_error(vi->i_sb, "First extent of attribute has "
1407                                        "non-zero lowest_vcn.");
1408                        goto unm_err_out;
1409                }
1410                vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1411                ni->initialized_size = sle64_to_cpu(
1412                                a->data.non_resident.initialized_size);
1413                ni->allocated_size = sle64_to_cpu(
1414                                a->data.non_resident.allocated_size);
1415        }
1416        if (NInoMstProtected(ni))
1417                vi->i_mapping->a_ops = &ntfs_mst_aops;
1418        else
1419                vi->i_mapping->a_ops = &ntfs_aops;
1420        if ((NInoCompressed(ni) || NInoSparse(ni)) && ni->type != AT_INDEX_ROOT)
1421                vi->i_blocks = ni->itype.compressed.size >> 9;
1422        else
1423                vi->i_blocks = ni->allocated_size >> 9;
1424        /*
1425         * Make sure the base inode does not go away and attach it to the
1426         * attribute inode.
1427         */
1428        igrab(base_vi);
1429        ni->ext.base_ntfs_ino = base_ni;
1430        ni->nr_extents = -1;
1431
1432        ntfs_attr_put_search_ctx(ctx);
1433        unmap_mft_record(base_ni);
1434
1435        ntfs_debug("Done.");
1436        return 0;
1437
1438unm_err_out:
1439        if (!err)
1440                err = -EIO;
1441        if (ctx)
1442                ntfs_attr_put_search_ctx(ctx);
1443        unmap_mft_record(base_ni);
1444err_out:
1445        ntfs_error(vol->sb, "Failed with error code %i while reading attribute "
1446                        "inode (mft_no 0x%lx, type 0x%x, name_len %i).  "
1447                        "Marking corrupt inode and base inode 0x%lx as bad.  "
1448                        "Run chkdsk.", err, vi->i_ino, ni->type, ni->name_len,
1449                        base_vi->i_ino);
1450        make_bad_inode(vi);
1451        if (err != -ENOMEM)
1452                NVolSetErrors(vol);
1453        return err;
1454}
1455
1456/**
1457 * ntfs_read_locked_index_inode - read an index inode from its base inode
1458 * @base_vi:    base inode
1459 * @vi:         index inode to read
1460 *
1461 * ntfs_read_locked_index_inode() is called from ntfs_index_iget() to read the
1462 * index inode described by @vi into memory from the base mft record described
1463 * by @base_ni.
1464 *
1465 * ntfs_read_locked_index_inode() maps, pins and locks the base inode for
1466 * reading and looks up the attributes relating to the index described by @vi
1467 * before setting up the necessary fields in @vi as well as initializing the
1468 * ntfs inode.
1469 *
1470 * Note, index inodes are essentially attribute inodes (NInoAttr() is true)
1471 * with the attribute type set to AT_INDEX_ALLOCATION.  Apart from that, they
1472 * are setup like directory inodes since directories are a special case of
1473 * indices ao they need to be treated in much the same way.  Most importantly,
1474 * for small indices the index allocation attribute might not actually exist.
1475 * However, the index root attribute always exists but this does not need to
1476 * have an inode associated with it and this is why we define a new inode type
1477 * index.  Also, like for directories, we need to have an attribute inode for
1478 * the bitmap attribute corresponding to the index allocation attribute and we
1479 * can store this in the appropriate field of the inode, just like we do for
1480 * normal directory inodes.
1481 *
1482 * Q: What locks are held when the function is called?
1483 * A: i_state has I_NEW set, hence the inode is locked, also
1484 *    i_count is set to 1, so it is not going to go away
1485 *
1486 * Return 0 on success and -errno on error.  In the error case, the inode will
1487 * have had make_bad_inode() executed on it.
1488 */
1489static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
1490{
1491        loff_t bvi_size;
1492        ntfs_volume *vol = NTFS_SB(vi->i_sb);
1493        ntfs_inode *ni, *base_ni, *bni;
1494        struct inode *bvi;
1495        MFT_RECORD *m;
1496        ATTR_RECORD *a;
1497        ntfs_attr_search_ctx *ctx;
1498        INDEX_ROOT *ir;
1499        u8 *ir_end, *index_end;
1500        int err = 0;
1501
1502        ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
1503        ntfs_init_big_inode(vi);
1504        ni      = NTFS_I(vi);
1505        base_ni = NTFS_I(base_vi);
1506        /* Just mirror the values from the base inode. */
1507        vi->i_version   = base_vi->i_version;
1508        vi->i_uid       = base_vi->i_uid;
1509        vi->i_gid       = base_vi->i_gid;
1510        set_nlink(vi, base_vi->i_nlink);
1511        vi->i_mtime     = base_vi->i_mtime;
1512        vi->i_ctime     = base_vi->i_ctime;
1513        vi->i_atime     = base_vi->i_atime;
1514        vi->i_generation = ni->seq_no = base_ni->seq_no;
1515        /* Set inode type to zero but preserve permissions. */
1516        vi->i_mode      = base_vi->i_mode & ~S_IFMT;
1517        /* Map the mft record for the base inode. */
1518        m = map_mft_record(base_ni);
1519        if (IS_ERR(m)) {
1520                err = PTR_ERR(m);
1521                goto err_out;
1522        }
1523        ctx = ntfs_attr_get_search_ctx(base_ni, m);
1524        if (!ctx) {
1525                err = -ENOMEM;
1526                goto unm_err_out;
1527        }
1528        /* Find the index root attribute. */
1529        err = ntfs_attr_lookup(AT_INDEX_ROOT, ni->name, ni->name_len,
1530                        CASE_SENSITIVE, 0, NULL, 0, ctx);
1531        if (unlikely(err)) {
1532                if (err == -ENOENT)
1533                        ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
1534                                        "missing.");
1535                goto unm_err_out;
1536        }
1537        a = ctx->attr;
1538        /* Set up the state. */
1539        if (unlikely(a->non_resident)) {
1540                ntfs_error(vol->sb, "$INDEX_ROOT attribute is not resident.");
1541                goto unm_err_out;
1542        }
1543        /* Ensure the attribute name is placed before the value. */
1544        if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1545                        le16_to_cpu(a->data.resident.value_offset)))) {
1546                ntfs_error(vol->sb, "$INDEX_ROOT attribute name is placed "
1547                                "after the attribute value.");
1548                goto unm_err_out;
1549        }
1550        /*
1551         * Compressed/encrypted/sparse index root is not allowed, except for
1552         * directories of course but those are not dealt with here.
1553         */
1554        if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_ENCRYPTED |
1555                        ATTR_IS_SPARSE)) {
1556                ntfs_error(vi->i_sb, "Found compressed/encrypted/sparse index "
1557                                "root attribute.");
1558                goto unm_err_out;
1559        }
1560        ir = (INDEX_ROOT*)((u8*)a + le16_to_cpu(a->data.resident.value_offset));
1561        ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
1562        if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
1563                ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is corrupt.");
1564                goto unm_err_out;
1565        }
1566        index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
1567        if (index_end > ir_end) {
1568                ntfs_error(vi->i_sb, "Index is corrupt.");
1569                goto unm_err_out;
1570        }
1571        if (ir->type) {
1572                ntfs_error(vi->i_sb, "Index type is not 0 (type is 0x%x).",
1573                                le32_to_cpu(ir->type));
1574                goto unm_err_out;
1575        }
1576        ni->itype.index.collation_rule = ir->collation_rule;
1577        ntfs_debug("Index collation rule is 0x%x.",
1578                        le32_to_cpu(ir->collation_rule));
1579        ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
1580        if (!is_power_of_2(ni->itype.index.block_size)) {
1581                ntfs_error(vi->i_sb, "Index block size (%u) is not a power of "
1582                                "two.", ni->itype.index.block_size);
1583                goto unm_err_out;
1584        }
1585        if (ni->itype.index.block_size > PAGE_CACHE_SIZE) {
1586                ntfs_error(vi->i_sb, "Index block size (%u) > PAGE_CACHE_SIZE "
1587                                "(%ld) is not supported.  Sorry.",
1588                                ni->itype.index.block_size, PAGE_CACHE_SIZE);
1589                err = -EOPNOTSUPP;
1590                goto unm_err_out;
1591        }
1592        if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
1593                ntfs_error(vi->i_sb, "Index block size (%u) < NTFS_BLOCK_SIZE "
1594                                "(%i) is not supported.  Sorry.",
1595                                ni->itype.index.block_size, NTFS_BLOCK_SIZE);
1596                err = -EOPNOTSUPP;
1597                goto unm_err_out;
1598        }
1599        ni->itype.index.block_size_bits = ffs(ni->itype.index.block_size) - 1;
1600        /* Determine the size of a vcn in the index. */
1601        if (vol->cluster_size <= ni->itype.index.block_size) {
1602                ni->itype.index.vcn_size = vol->cluster_size;
1603                ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
1604        } else {
1605                ni->itype.index.vcn_size = vol->sector_size;
1606                ni->itype.index.vcn_size_bits = vol->sector_size_bits;
1607        }
1608        /* Check for presence of index allocation attribute. */
1609        if (!(ir->index.flags & LARGE_INDEX)) {
1610                /* No index allocation. */
1611                vi->i_size = ni->initialized_size = ni->allocated_size = 0;
1612                /* We are done with the mft record, so we release it. */
1613                ntfs_attr_put_search_ctx(ctx);
1614                unmap_mft_record(base_ni);
1615                m = NULL;
1616                ctx = NULL;
1617                goto skip_large_index_stuff;
1618        } /* LARGE_INDEX:  Index allocation present.  Setup state. */
1619        NInoSetIndexAllocPresent(ni);
1620        /* Find index allocation attribute. */
1621        ntfs_attr_reinit_search_ctx(ctx);
1622        err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, ni->name, ni->name_len,
1623                        CASE_SENSITIVE, 0, NULL, 0, ctx);
1624        if (unlikely(err)) {
1625                if (err == -ENOENT)
1626                        ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1627                                        "not present but $INDEX_ROOT "
1628                                        "indicated it is.");
1629                else
1630                        ntfs_error(vi->i_sb, "Failed to lookup "
1631                                        "$INDEX_ALLOCATION attribute.");
1632                goto unm_err_out;
1633        }
1634        a = ctx->attr;
1635        if (!a->non_resident) {
1636                ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1637                                "resident.");
1638                goto unm_err_out;
1639        }
1640        /*
1641         * Ensure the attribute name is placed before the mapping pairs array.
1642         */
1643        if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
1644                        le16_to_cpu(
1645                        a->data.non_resident.mapping_pairs_offset)))) {
1646                ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name is "
1647                                "placed after the mapping pairs array.");
1648                goto unm_err_out;
1649        }
1650        if (a->flags & ATTR_IS_ENCRYPTED) {
1651                ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1652                                "encrypted.");
1653                goto unm_err_out;
1654        }
1655        if (a->flags & ATTR_IS_SPARSE) {
1656                ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is sparse.");
1657                goto unm_err_out;
1658        }
1659        if (a->flags & ATTR_COMPRESSION_MASK) {
1660                ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
1661                                "compressed.");
1662                goto unm_err_out;
1663        }
1664        if (a->data.non_resident.lowest_vcn) {
1665                ntfs_error(vi->i_sb, "First extent of $INDEX_ALLOCATION "
1666                                "attribute has non zero lowest_vcn.");
1667                goto unm_err_out;
1668        }
1669        vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
1670        ni->initialized_size = sle64_to_cpu(
1671                        a->data.non_resident.initialized_size);
1672        ni->allocated_size = sle64_to_cpu(a->data.non_resident.allocated_size);
1673        /*
1674         * We are done with the mft record, so we release it.  Otherwise
1675         * we would deadlock in ntfs_attr_iget().
1676         */
1677        ntfs_attr_put_search_ctx(ctx);
1678        unmap_mft_record(base_ni);
1679        m = NULL;
1680        ctx = NULL;
1681        /* Get the index bitmap attribute inode. */
1682        bvi = ntfs_attr_iget(base_vi, AT_BITMAP, ni->name, ni->name_len);
1683        if (IS_ERR(bvi)) {
1684                ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
1685                err = PTR_ERR(bvi);
1686                goto unm_err_out;
1687        }
1688        bni = NTFS_I(bvi);
1689        if (NInoCompressed(bni) || NInoEncrypted(bni) ||
1690                        NInoSparse(bni)) {
1691                ntfs_error(vi->i_sb, "$BITMAP attribute is compressed and/or "
1692                                "encrypted and/or sparse.");
1693                goto iput_unm_err_out;
1694        }
1695        /* Consistency check bitmap size vs. index allocation size. */
1696        bvi_size = i_size_read(bvi);
1697        if ((bvi_size << 3) < (vi->i_size >> ni->itype.index.block_size_bits)) {
1698                ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) for "
1699                                "index allocation (0x%llx).", bvi_size << 3,
1700                                vi->i_size);
1701                goto iput_unm_err_out;
1702        }
1703        iput(bvi);
1704skip_large_index_stuff:
1705        /* Setup the operations for this index inode. */
1706        vi->i_op = NULL;
1707        vi->i_fop = NULL;
1708        vi->i_mapping->a_ops = &ntfs_mst_aops;
1709        vi->i_blocks = ni->allocated_size >> 9;
1710        /*
1711         * Make sure the base inode doesn't go away and attach it to the
1712         * index inode.
1713         */
1714        igrab(base_vi);
1715        ni->ext.base_ntfs_ino = base_ni;
1716        ni->nr_extents = -1;
1717
1718        ntfs_debug("Done.");
1719        return 0;
1720iput_unm_err_out:
1721        iput(bvi);
1722unm_err_out:
1723        if (!err)
1724                err = -EIO;
1725        if (ctx)
1726                ntfs_attr_put_search_ctx(ctx);
1727        if (m)
1728                unmap_mft_record(base_ni);
1729err_out:
1730        ntfs_error(vi->i_sb, "Failed with error code %i while reading index "
1731                        "inode (mft_no 0x%lx, name_len %i.", err, vi->i_ino,
1732                        ni->name_len);
1733        make_bad_inode(vi);
1734        if (err != -EOPNOTSUPP && err != -ENOMEM)
1735                NVolSetErrors(vol);
1736        return err;
1737}
1738
1739/*
1740 * The MFT inode has special locking, so teach the lock validator
1741 * about this by splitting off the locking rules of the MFT from
1742 * the locking rules of other inodes. The MFT inode can never be
1743 * accessed from the VFS side (or even internally), only by the
1744 * map_mft functions.
1745 */
1746static struct lock_class_key mft_ni_runlist_lock_key, mft_ni_mrec_lock_key;
1747
1748/**
1749 * ntfs_read_inode_mount - special read_inode for mount time use only
1750 * @vi:         inode to read
1751 *
1752 * Read inode FILE_MFT at mount time, only called with super_block lock
1753 * held from within the read_super() code path.
1754 *
1755 * This function exists because when it is called the page cache for $MFT/$DATA
1756 * is not initialized and hence we cannot get at the contents of mft records
1757 * by calling map_mft_record*().
1758 *
1759 * Further it needs to cope with the circular references problem, i.e. cannot
1760 * load any attributes other than $ATTRIBUTE_LIST until $DATA is loaded, because
1761 * we do not know where the other extent mft records are yet and again, because
1762 * we cannot call map_mft_record*() yet.  Obviously this applies only when an
1763 * attribute list is actually present in $MFT inode.
1764 *
1765 * We solve these problems by starting with the $DATA attribute before anything
1766 * else and iterating using ntfs_attr_lookup($DATA) over all extents.  As each
1767 * extent is found, we ntfs_mapping_pairs_decompress() including the implied
1768 * ntfs_runlists_merge().  Each step of the iteration necessarily provides
1769 * sufficient information for the next step to complete.
1770 *
1771 * This should work but there are two possible pit falls (see inline comments
1772 * below), but only time will tell if they are real pits or just smoke...
1773 */
1774int ntfs_read_inode_mount(struct inode *vi)
1775{
1776        VCN next_vcn, last_vcn, highest_vcn;
1777        s64 block;
1778        struct super_block *sb = vi->i_sb;
1779        ntfs_volume *vol = NTFS_SB(sb);
1780        struct buffer_head *bh;
1781        ntfs_inode *ni;
1782        MFT_RECORD *m = NULL;
1783        ATTR_RECORD *a;
1784        ntfs_attr_search_ctx *ctx;
1785        unsigned int i, nr_blocks;
1786        int err;
1787
1788        ntfs_debug("Entering.");
1789
1790        /* Initialize the ntfs specific part of @vi. */
1791        ntfs_init_big_inode(vi);
1792
1793        ni = NTFS_I(vi);
1794
1795        /* Setup the data attribute. It is special as it is mst protected. */
1796        NInoSetNonResident(ni);
1797        NInoSetMstProtected(ni);
1798        NInoSetSparseDisabled(ni);
1799        ni->type = AT_DATA;
1800        ni->name = NULL;
1801        ni->name_len = 0;
1802        /*
1803         * This sets up our little cheat allowing us to reuse the async read io
1804         * completion handler for directories.
1805         */
1806        ni->itype.index.block_size = vol->mft_record_size;
1807        ni->itype.index.block_size_bits = vol->mft_record_size_bits;
1808
1809        /* Very important! Needed to be able to call map_mft_record*(). */
1810        vol->mft_ino = vi;
1811
1812        /* Allocate enough memory to read the first mft record. */
1813        if (vol->mft_record_size > 64 * 1024) {
1814                ntfs_error(sb, "Unsupported mft record size %i (max 64kiB).",
1815                                vol->mft_record_size);
1816                goto err_out;
1817        }
1818        i = vol->mft_record_size;
1819        if (i < sb->s_blocksize)
1820                i = sb->s_blocksize;
1821        m = (MFT_RECORD*)ntfs_malloc_nofs(i);
1822        if (!m) {
1823                ntfs_error(sb, "Failed to allocate buffer for $MFT record 0.");
1824                goto err_out;
1825        }
1826
1827        /* Determine the first block of the $MFT/$DATA attribute. */
1828        block = vol->mft_lcn << vol->cluster_size_bits >>
1829                        sb->s_blocksize_bits;
1830        nr_blocks = vol->mft_record_size >> sb->s_blocksize_bits;
1831        if (!nr_blocks)
1832                nr_blocks = 1;
1833
1834        /* Load $MFT/$DATA's first mft record. */
1835        for (i = 0; i < nr_blocks; i++) {
1836                bh = sb_bread(sb, block++);
1837                if (!bh) {
1838                        ntfs_error(sb, "Device read failed.");
1839                        goto err_out;
1840                }
1841                memcpy((char*)m + (i << sb->s_blocksize_bits), bh->b_data,
1842                                sb->s_blocksize);
1843                brelse(bh);
1844        }
1845
1846        /* Apply the mst fixups. */
1847        if (post_read_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size)) {
1848                /* FIXME: Try to use the $MFTMirr now. */
1849                ntfs_error(sb, "MST fixup failed. $MFT is corrupt.");
1850                goto err_out;
1851        }
1852
1853        /* Need this to sanity check attribute list references to $MFT. */
1854        vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);
1855
1856        /* Provides readpage() and sync_page() for map_mft_record(). */
1857        vi->i_mapping->a_ops = &ntfs_mst_aops;
1858
1859        ctx = ntfs_attr_get_search_ctx(ni, m);
1860        if (!ctx) {
1861                err = -ENOMEM;
1862                goto err_out;
1863        }
1864
1865        /* Find the attribute list attribute if present. */
1866        err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
1867        if (err) {
1868                if (unlikely(err != -ENOENT)) {
1869                        ntfs_error(sb, "Failed to lookup attribute list "
1870                                        "attribute. You should run chkdsk.");
1871                        goto put_err_out;
1872                }
1873        } else /* if (!err) */ {
1874                ATTR_LIST_ENTRY *al_entry, *next_al_entry;
1875                u8 *al_end;
1876                static const char *es = "  Not allowed.  $MFT is corrupt.  "
1877                                "You should run chkdsk.";
1878
1879                ntfs_debug("Attribute list attribute found in $MFT.");
1880                NInoSetAttrList(ni);
1881                a = ctx->attr;
1882                if (a->flags & ATTR_COMPRESSION_MASK) {
1883                        ntfs_error(sb, "Attribute list attribute is "
1884                                        "compressed.%s", es);
1885                        goto put_err_out;
1886                }
1887                if (a->flags & ATTR_IS_ENCRYPTED ||
1888                                a->flags & ATTR_IS_SPARSE) {
1889                        if (a->non_resident) {
1890                                ntfs_error(sb, "Non-resident attribute list "
1891                                                "attribute is encrypted/"
1892                                                "sparse.%s", es);
1893                                goto put_err_out;
1894                        }
1895                        ntfs_warning(sb, "Resident attribute list attribute "
1896                                        "in $MFT system file is marked "
1897                                        "encrypted/sparse which is not true.  "
1898                                        "However, Windows allows this and "
1899                                        "chkdsk does not detect or correct it "
1900                                        "so we will just ignore the invalid "
1901                                        "flags and pretend they are not set.");
1902                }
1903                /* Now allocate memory for the attribute list. */
1904                ni->attr_list_size = (u32)ntfs_attr_size(a);
1905                ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
1906                if (!ni->attr_list) {
1907                        ntfs_error(sb, "Not enough memory to allocate buffer "
1908                                        "for attribute list.");
1909                        goto put_err_out;
1910                }
1911                if (a->non_resident) {
1912                        NInoSetAttrListNonResident(ni);
1913                        if (a->data.non_resident.lowest_vcn) {
1914                                ntfs_error(sb, "Attribute list has non zero "
1915                                                "lowest_vcn. $MFT is corrupt. "
1916                                                "You should run chkdsk.");
1917                                goto put_err_out;
1918                        }
1919                        /* Setup the runlist. */
1920                        ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
1921                                        a, NULL);
1922                        if (IS_ERR(ni->attr_list_rl.rl)) {
1923                                err = PTR_ERR(ni->attr_list_rl.rl);
1924                                ni->attr_list_rl.rl = NULL;
1925                                ntfs_error(sb, "Mapping pairs decompression "
1926                                                "failed with error code %i.",
1927                                                -err);
1928                                goto put_err_out;
1929                        }
1930                        /* Now load the attribute list. */
1931                        if ((err = load_attribute_list(vol, &ni->attr_list_rl,
1932                                        ni->attr_list, ni->attr_list_size,
1933                                        sle64_to_cpu(a->data.
1934                                        non_resident.initialized_size)))) {
1935                                ntfs_error(sb, "Failed to load attribute list "
1936                                                "attribute with error code %i.",
1937                                                -err);
1938                                goto put_err_out;
1939                        }
1940                } else /* if (!ctx.attr->non_resident) */ {
1941                        if ((u8*)a + le16_to_cpu(
1942                                        a->data.resident.value_offset) +
1943                                        le32_to_cpu(
1944                                        a->data.resident.value_length) >
1945                                        (u8*)ctx->mrec + vol->mft_record_size) {
1946                                ntfs_error(sb, "Corrupt attribute list "
1947                                                "attribute.");
1948                                goto put_err_out;
1949                        }
1950                        /* Now copy the attribute list. */
1951                        memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
1952                                        a->data.resident.value_offset),
1953                                        le32_to_cpu(
1954                                        a->data.resident.value_length));
1955                }
1956                /* The attribute list is now setup in memory. */
1957                /*
1958                 * FIXME: I don't know if this case is actually possible.
1959                 * According to logic it is not possible but I have seen too
1960                 * many weird things in MS software to rely on logic... Thus we
1961                 * perform a manual search and make sure the first $MFT/$DATA
1962                 * extent is in the base inode. If it is not we abort with an
1963                 * error and if we ever see a report of this error we will need
1964                 * to do some magic in order to have the necessary mft record
1965                 * loaded and in the right place in the page cache. But
1966                 * hopefully logic will prevail and this never happens...
1967                 */
1968                al_entry = (ATTR_LIST_ENTRY*)ni->attr_list;
1969                al_end = (u8*)al_entry + ni->attr_list_size;
1970                for (;; al_entry = next_al_entry) {
1971                        /* Out of bounds check. */
1972                        if ((u8*)al_entry < ni->attr_list ||
1973                                        (u8*)al_entry > al_end)
1974                                goto em_put_err_out;
1975                        /* Catch the end of the attribute list. */
1976                        if ((u8*)al_entry == al_end)
1977                                goto em_put_err_out;
1978                        if (!al_entry->length)
1979                                goto em_put_err_out;
1980                        if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
1981                                        le16_to_cpu(al_entry->length) > al_end)
1982                                goto em_put_err_out;
1983                        next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
1984                                        le16_to_cpu(al_entry->length));
1985                        if (le32_to_cpu(al_entry->type) > le32_to_cpu(AT_DATA))
1986                                goto em_put_err_out;
1987                        if (AT_DATA != al_entry->type)
1988                                continue;
1989                        /* We want an unnamed attribute. */
1990                        if (al_entry->name_length)
1991                                goto em_put_err_out;
1992                        /* Want the first entry, i.e. lowest_vcn == 0. */
1993                        if (al_entry->lowest_vcn)
1994                                goto em_put_err_out;
1995                        /* First entry has to be in the base mft record. */
1996                        if (MREF_LE(al_entry->mft_reference) != vi->i_ino) {
1997                                /* MFT references do not match, logic fails. */
1998                                ntfs_error(sb, "BUG: The first $DATA extent "
1999                                                "of $MFT is not in the base "
2000                                                "mft record. Please report "
2001                                                "you saw this message to "
2002                                                "linux-ntfs-dev@lists."
2003                                                "sourceforge.net");
2004                                goto put_err_out;
2005                        } else {
2006                                /* Sequence numbers must match. */
2007                                if (MSEQNO_LE(al_entry->mft_reference) !=
2008                                                ni->seq_no)
2009                                        goto em_put_err_out;
2010                                /* Got it. All is ok. We can stop now. */
2011                                break;
2012                        }
2013                }
2014        }
2015
2016        ntfs_attr_reinit_search_ctx(ctx);
2017
2018        /* Now load all attribute extents. */
2019        a = NULL;
2020        next_vcn = last_vcn = highest_vcn = 0;
2021        while (!(err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, next_vcn, NULL, 0,
2022                        ctx))) {
2023                runlist_element *nrl;
2024
2025                /* Cache the current attribute. */
2026                a = ctx->attr;
2027                /* $MFT must be non-resident. */
2028                if (!a->non_resident) {
2029                        ntfs_error(sb, "$MFT must be non-resident but a "
2030                                        "resident extent was found. $MFT is "
2031                                        "corrupt. Run chkdsk.");
2032                        goto put_err_out;
2033                }
2034                /* $MFT must be uncompressed and unencrypted. */
2035                if (a->flags & ATTR_COMPRESSION_MASK ||
2036                                a->flags & ATTR_IS_ENCRYPTED ||
2037                                a->flags & ATTR_IS_SPARSE) {
2038                        ntfs_error(sb, "$MFT must be uncompressed, "
2039                                        "non-sparse, and unencrypted but a "
2040                                        "compressed/sparse/encrypted extent "
2041                                        "was found. $MFT is corrupt. Run "
2042                                        "chkdsk.");
2043                        goto put_err_out;
2044                }
2045                /*
2046                 * Decompress the mapping pairs array of this extent and merge
2047                 * the result into the existing runlist. No need for locking
2048                 * as we have exclusive access to the inode at this time and we
2049                 * are a mount in progress task, too.
2050                 */
2051                nrl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
2052                if (IS_ERR(nrl)) {
2053                        ntfs_error(sb, "ntfs_mapping_pairs_decompress() "
2054                                        "failed with error code %ld.  $MFT is "
2055                                        "corrupt.", PTR_ERR(nrl));
2056                        goto put_err_out;
2057                }
2058                ni->runlist.rl = nrl;
2059
2060                /* Are we in the first extent? */
2061                if (!next_vcn) {
2062                        if (a->data.non_resident.lowest_vcn) {
2063                                ntfs_error(sb, "First extent of $DATA "
2064                                                "attribute has non zero "
2065                                                "lowest_vcn. $MFT is corrupt. "
2066                                                "You should run chkdsk.");
2067                                goto put_err_out;
2068                        }
2069                        /* Get the last vcn in the $DATA attribute. */
2070                        last_vcn = sle64_to_cpu(
2071                                        a->data.non_resident.allocated_size)
2072                                        >> vol->cluster_size_bits;
2073                        /* Fill in the inode size. */
2074                        vi->i_size = sle64_to_cpu(
2075                                        a->data.non_resident.data_size);
2076                        ni->initialized_size = sle64_to_cpu(
2077                                        a->data.non_resident.initialized_size);
2078                        ni->allocated_size = sle64_to_cpu(
2079                                        a->data.non_resident.allocated_size);
2080                        /*
2081                         * Verify the number of mft records does not exceed
2082                         * 2^32 - 1.
2083                         */
2084                        if ((vi->i_size >> vol->mft_record_size_bits) >=
2085                                        (1ULL << 32)) {
2086                                ntfs_error(sb, "$MFT is too big! Aborting.");
2087                                goto put_err_out;
2088                        }
2089                        /*
2090                         * We have got the first extent of the runlist for
2091                         * $MFT which means it is now relatively safe to call
2092                         * the normal ntfs_read_inode() function.
2093                         * Complete reading the inode, this will actually
2094                         * re-read the mft record for $MFT, this time entering
2095                         * it into the page cache with which we complete the
2096                         * kick start of the volume. It should be safe to do
2097                         * this now as the first extent of $MFT/$DATA is
2098                         * already known and we would hope that we don't need
2099                         * further extents in order to find the other
2100                         * attributes belonging to $MFT. Only time will tell if
2101                         * this is really the case. If not we will have to play
2102                         * magic at this point, possibly duplicating a lot of
2103                         * ntfs_read_inode() at this point. We will need to
2104                         * ensure we do enough of its work to be able to call
2105                         * ntfs_read_inode() on extents of $MFT/$DATA. But lets
2106                         * hope this never happens...
2107                         */
2108                        ntfs_read_locked_inode(vi);
2109                        if (is_bad_inode(vi)) {
2110                                ntfs_error(sb, "ntfs_read_inode() of $MFT "
2111                                                "failed. BUG or corrupt $MFT. "
2112                                                "Run chkdsk and if no errors "
2113                                                "are found, please report you "
2114                                                "saw this message to "
2115                                                "linux-ntfs-dev@lists."
2116                                                "sourceforge.net");
2117                                ntfs_attr_put_search_ctx(ctx);
2118                                /* Revert to the safe super operations. */
2119                                ntfs_free(m);
2120                                return -1;
2121                        }
2122                        /*
2123                         * Re-initialize some specifics about $MFT's inode as
2124                         * ntfs_read_inode() will have set up the default ones.
2125                         */
2126                        /* Set uid and gid to root. */
2127                        vi->i_uid = vi->i_gid = 0;
2128                        /* Regular file. No access for anyone. */
2129                        vi->i_mode = S_IFREG;
2130                        /* No VFS initiated operations allowed for $MFT. */
2131                        vi->i_op = &ntfs_empty_inode_ops;
2132                        vi->i_fop = &ntfs_empty_file_ops;
2133                }
2134
2135                /* Get the lowest vcn for the next extent. */
2136                highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2137                next_vcn = highest_vcn + 1;
2138
2139                /* Only one extent or error, which we catch below. */
2140                if (next_vcn <= 0)
2141                        break;
2142
2143                /* Avoid endless loops due to corruption. */
2144                if (next_vcn < sle64_to_cpu(
2145                                a->data.non_resident.lowest_vcn)) {
2146                        ntfs_error(sb, "$MFT has corrupt attribute list "
2147                                        "attribute. Run chkdsk.");
2148                        goto put_err_out;
2149                }
2150        }
2151        if (err != -ENOENT) {
2152                ntfs_error(sb, "Failed to lookup $MFT/$DATA attribute extent. "
2153                                "$MFT is corrupt. Run chkdsk.");
2154                goto put_err_out;
2155        }
2156        if (!a) {
2157                ntfs_error(sb, "$MFT/$DATA attribute not found. $MFT is "
2158                                "corrupt. Run chkdsk.");
2159                goto put_err_out;
2160        }
2161        if (highest_vcn && highest_vcn != last_vcn - 1) {
2162                ntfs_error(sb, "Failed to load the complete runlist for "
2163                                "$MFT/$DATA. Driver bug or corrupt $MFT. "
2164                                "Run chkdsk.");
2165                ntfs_debug("highest_vcn = 0x%llx, last_vcn - 1 = 0x%llx",
2166                                (unsigned long long)highest_vcn,
2167                                (unsigned long long)last_vcn - 1);
2168                goto put_err_out;
2169        }
2170        ntfs_attr_put_search_ctx(ctx);
2171        ntfs_debug("Done.");
2172        ntfs_free(m);
2173
2174        /*
2175         * Split the locking rules of the MFT inode from the
2176         * locking rules of other inodes:
2177         */
2178        lockdep_set_class(&ni->runlist.lock, &mft_ni_runlist_lock_key);
2179        lockdep_set_class(&ni->mrec_lock, &mft_ni_mrec_lock_key);
2180
2181        return 0;
2182
2183em_put_err_out:
2184        ntfs_error(sb, "Couldn't find first extent of $DATA attribute in "
2185                        "attribute list. $MFT is corrupt. Run chkdsk.");
2186put_err_out:
2187        ntfs_attr_put_search_ctx(ctx);
2188err_out:
2189        ntfs_error(sb, "Failed. Marking inode as bad.");
2190        make_bad_inode(vi);
2191        ntfs_free(m);
2192        return -1;
2193}
2194
2195static void __ntfs_clear_inode(ntfs_inode *ni)
2196{
2197        /* Free all alocated memory. */
2198        down_write(&ni->runlist.lock);
2199        if (ni->runlist.rl) {
2200                ntfs_free(ni->runlist.rl);
2201                ni->runlist.rl = NULL;
2202        }
2203        up_write(&ni->runlist.lock);
2204
2205        if (ni->attr_list) {
2206                ntfs_free(ni->attr_list);
2207                ni->attr_list = NULL;
2208        }
2209
2210        down_write(&ni->attr_list_rl.lock);
2211        if (ni->attr_list_rl.rl) {
2212                ntfs_free(ni->attr_list_rl.rl);
2213                ni->attr_list_rl.rl = NULL;
2214        }
2215        up_write(&ni->attr_list_rl.lock);
2216
2217        if (ni->name_len && ni->name != I30) {
2218                /* Catch bugs... */
2219                BUG_ON(!ni->name);
2220                kfree(ni->name);
2221        }
2222}
2223
2224void ntfs_clear_extent_inode(ntfs_inode *ni)
2225{
2226        ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);
2227
2228        BUG_ON(NInoAttr(ni));
2229        BUG_ON(ni->nr_extents != -1);
2230
2231#ifdef NTFS_RW
2232        if (NInoDirty(ni)) {
2233                if (!is_bad_inode(VFS_I(ni->ext.base_ntfs_ino)))
2234                        ntfs_error(ni->vol->sb, "Clearing dirty extent inode!  "
2235                                        "Losing data!  This is a BUG!!!");
2236                // FIXME:  Do something!!!
2237        }
2238#endif /* NTFS_RW */
2239
2240        __ntfs_clear_inode(ni);
2241
2242        /* Bye, bye... */
2243        ntfs_destroy_extent_inode(ni);
2244}
2245
2246/**
2247 * ntfs_evict_big_inode - clean up the ntfs specific part of an inode
2248 * @vi:         vfs inode pending annihilation
2249 *
2250 * When the VFS is going to remove an inode from memory, ntfs_clear_big_inode()
2251 * is called, which deallocates all memory belonging to the NTFS specific part
2252 * of the inode and returns.
2253 *
2254 * If the MFT record is dirty, we commit it before doing anything else.
2255 */
2256void ntfs_evict_big_inode(struct inode *vi)
2257{
2258        ntfs_inode *ni = NTFS_I(vi);
2259
2260        truncate_inode_pages(&vi->i_data, 0);
2261        clear_inode(vi);
2262
2263#ifdef NTFS_RW
2264        if (NInoDirty(ni)) {
2265                bool was_bad = (is_bad_inode(vi));
2266
2267                /* Committing the inode also commits all extent inodes. */
2268                ntfs_commit_inode(vi);
2269
2270                if (!was_bad && (is_bad_inode(vi) || NInoDirty(ni))) {
2271                        ntfs_error(vi->i_sb, "Failed to commit dirty inode "
2272                                        "0x%lx.  Losing data!", vi->i_ino);
2273                        // FIXME:  Do something!!!
2274                }
2275        }
2276#endif /* NTFS_RW */
2277
2278        /* No need to lock at this stage as no one else has a reference. */
2279        if (ni->nr_extents > 0) {
2280                int i;
2281
2282                for (i = 0; i < ni->nr_extents; i++)
2283                        ntfs_clear_extent_inode(ni->ext.extent_ntfs_inos[i]);
2284                kfree(ni->ext.extent_ntfs_inos);
2285        }
2286
2287        __ntfs_clear_inode(ni);
2288
2289        if (NInoAttr(ni)) {
2290                /* Release the base inode if we are holding it. */
2291                if (ni->nr_extents == -1) {
2292                        iput(VFS_I(ni->ext.base_ntfs_ino));
2293                        ni->nr_extents = 0;
2294                        ni->ext.base_ntfs_ino = NULL;
2295                }
2296        }
2297        return;
2298}
2299
2300/**
2301 * ntfs_show_options - show mount options in /proc/mounts
2302 * @sf:         seq_file in which to write our mount options
2303 * @root:       root of the mounted tree whose mount options to display
2304 *
2305 * Called by the VFS once for each mounted ntfs volume when someone reads
2306 * /proc/mounts in order to display the NTFS specific mount options of each
2307 * mount. The mount options of fs specified by @root are written to the seq file
2308 * @sf and success is returned.
2309 */
2310int ntfs_show_options(struct seq_file *sf, struct dentry *root)
2311{
2312        ntfs_volume *vol = NTFS_SB(root->d_sb);
2313        int i;
2314
2315        seq_printf(sf, ",uid=%i", vol->uid);
2316        seq_printf(sf, ",gid=%i", vol->gid);
2317        if (vol->fmask == vol->dmask)
2318                seq_printf(sf, ",umask=0%o", vol->fmask);
2319        else {
2320                seq_printf(sf, ",fmask=0%o", vol->fmask);
2321                seq_printf(sf, ",dmask=0%o", vol->dmask);
2322        }
2323        seq_printf(sf, ",nls=%s", vol->nls_map->charset);
2324        if (NVolCaseSensitive(vol))
2325                seq_printf(sf, ",case_sensitive");
2326        if (NVolShowSystemFiles(vol))
2327                seq_printf(sf, ",show_sys_files");
2328        if (!NVolSparseEnabled(vol))
2329                seq_printf(sf, ",disable_sparse");
2330        for (i = 0; on_errors_arr[i].val; i++) {
2331                if (on_errors_arr[i].val & vol->on_errors)
2332                        seq_printf(sf, ",errors=%s", on_errors_arr[i].str);
2333        }
2334        seq_printf(sf, ",mft_zone_multiplier=%i", vol->mft_zone_multiplier);
2335        return 0;
2336}
2337
2338#ifdef NTFS_RW
2339
2340static const char *es = "  Leaving inconsistent metadata.  Unmount and run "
2341                "chkdsk.";
2342
2343/**
2344 * ntfs_truncate - called when the i_size of an ntfs inode is changed
2345 * @vi:         inode for which the i_size was changed
2346 *
2347 * We only support i_size changes for normal files at present, i.e. not
2348 * compressed and not encrypted.  This is enforced in ntfs_setattr(), see
2349 * below.
2350 *
2351 * The kernel guarantees that @vi is a regular file (S_ISREG() is true) and
2352 * that the change is allowed.
2353 *
2354 * This implies for us that @vi is a file inode rather than a directory, index,
2355 * or attribute inode as well as that @vi is a base inode.
2356 *
2357 * Returns 0 on success or -errno on error.
2358 *
2359 * Called with ->i_mutex held.
2360 */
2361int ntfs_truncate(struct inode *vi)
2362{
2363        s64 new_size, old_size, nr_freed, new_alloc_size, old_alloc_size;
2364        VCN highest_vcn;
2365        unsigned long flags;
2366        ntfs_inode *base_ni, *ni = NTFS_I(vi);
2367        ntfs_volume *vol = ni->vol;
2368        ntfs_attr_search_ctx *ctx;
2369        MFT_RECORD *m;
2370        ATTR_RECORD *a;
2371        const char *te = "  Leaving file length out of sync with i_size.";
2372        int err, mp_size, size_change, alloc_change;
2373        u32 attr_len;
2374
2375        ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
2376        BUG_ON(NInoAttr(ni));
2377        BUG_ON(S_ISDIR(vi->i_mode));
2378        BUG_ON(NInoMstProtected(ni));
2379        BUG_ON(ni->nr_extents < 0);
2380retry_truncate:
2381        /*
2382         * Lock the runlist for writing and map the mft record to ensure it is
2383         * safe to mess with the attribute runlist and sizes.
2384         */
2385        down_write(&ni->runlist.lock);
2386        if (!NInoAttr(ni))
2387                base_ni = ni;
2388        else
2389                base_ni = ni->ext.base_ntfs_ino;
2390        m = map_mft_record(base_ni);
2391        if (IS_ERR(m)) {
2392                err = PTR_ERR(m);
2393                ntfs_error(vi->i_sb, "Failed to map mft record for inode 0x%lx "
2394                                "(error code %d).%s", vi->i_ino, err, te);
2395                ctx = NULL;
2396                m = NULL;
2397                goto old_bad_out;
2398        }
2399        ctx = ntfs_attr_get_search_ctx(base_ni, m);
2400        if (unlikely(!ctx)) {
2401                ntfs_error(vi->i_sb, "Failed to allocate a search context for "
2402                                "inode 0x%lx (not enough memory).%s",
2403                                vi->i_ino, te);
2404                err = -ENOMEM;
2405                goto old_bad_out;
2406        }
2407        err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
2408                        CASE_SENSITIVE, 0, NULL, 0, ctx);
2409        if (unlikely(err)) {
2410                if (err == -ENOENT) {
2411                        ntfs_error(vi->i_sb, "Open attribute is missing from "
2412                                        "mft record.  Inode 0x%lx is corrupt.  "
2413                                        "Run chkdsk.%s", vi->i_ino, te);
2414                        err = -EIO;
2415                } else
2416                        ntfs_error(vi->i_sb, "Failed to lookup attribute in "
2417                                        "inode 0x%lx (error code %d).%s",
2418                                        vi->i_ino, err, te);
2419                goto old_bad_out;
2420        }
2421        m = ctx->mrec;
2422        a = ctx->attr;
2423        /*
2424         * The i_size of the vfs inode is the new size for the attribute value.
2425         */
2426        new_size = i_size_read(vi);
2427        /* The current size of the attribute value is the old size. */
2428        old_size = ntfs_attr_size(a);
2429        /* Calculate the new allocated size. */
2430        if (NInoNonResident(ni))
2431                new_alloc_size = (new_size + vol->cluster_size - 1) &
2432                                ~(s64)vol->cluster_size_mask;
2433        else
2434                new_alloc_size = (new_size + 7) & ~7;
2435        /* The current allocated size is the old allocated size. */
2436        read_lock_irqsave(&ni->size_lock, flags);
2437        old_alloc_size = ni->allocated_size;
2438        read_unlock_irqrestore(&ni->size_lock, flags);
2439        /*
2440         * The change in the file size.  This will be 0 if no change, >0 if the
2441         * size is growing, and <0 if the size is shrinking.
2442         */
2443        size_change = -1;
2444        if (new_size - old_size >= 0) {
2445                size_change = 1;
2446                if (new_size == old_size)
2447                        size_change = 0;
2448        }
2449        /* As above for the allocated size. */
2450        alloc_change = -1;
2451        if (new_alloc_size - old_alloc_size >= 0) {
2452                alloc_change = 1;
2453                if (new_alloc_size == old_alloc_size)
2454                        alloc_change = 0;
2455        }
2456        /*
2457         * If neither the size nor the allocation are being changed there is
2458         * nothing to do.
2459         */
2460        if (!size_change && !alloc_change)
2461                goto unm_done;
2462        /* If the size is changing, check if new size is allowed in $AttrDef. */
2463        if (size_change) {
2464                err = ntfs_attr_size_bounds_check(vol, ni->type, new_size);
2465                if (unlikely(err)) {
2466                        if (err == -ERANGE) {
2467                                ntfs_error(vol->sb, "Truncate would cause the "
2468                                                "inode 0x%lx to %simum size "
2469                                                "for its attribute type "
2470                                                "(0x%x).  Aborting truncate.",
2471                                                vi->i_ino,
2472                                                new_size > old_size ? "exceed "
2473                                                "the max" : "go under the min",
2474                                                le32_to_cpu(ni->type));
2475                                err = -EFBIG;
2476                        } else {
2477                                ntfs_error(vol->sb, "Inode 0x%lx has unknown "
2478                                                "attribute type 0x%x.  "
2479                                                "Aborting truncate.",
2480                                                vi->i_ino,
2481                                                le32_to_cpu(ni->type));
2482                                err = -EIO;
2483                        }
2484                        /* Reset the vfs inode size to the old size. */
2485                        i_size_write(vi, old_size);
2486                        goto err_out;
2487                }
2488        }
2489        if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2490                ntfs_warning(vi->i_sb, "Changes in inode size are not "
2491                                "supported yet for %s files, ignoring.",
2492                                NInoCompressed(ni) ? "compressed" :
2493                                "encrypted");
2494                err = -EOPNOTSUPP;
2495                goto bad_out;
2496        }
2497        if (a->non_resident)
2498                goto do_non_resident_truncate;
2499        BUG_ON(NInoNonResident(ni));
2500        /* Resize the attribute record to best fit the new attribute size. */
2501        if (new_size < vol->mft_record_size &&
2502                        !ntfs_resident_attr_value_resize(m, a, new_size)) {
2503                /* The resize succeeded! */
2504                flush_dcache_mft_record_page(ctx->ntfs_ino);
2505                mark_mft_record_dirty(ctx->ntfs_ino);
2506                write_lock_irqsave(&ni->size_lock, flags);
2507                /* Update the sizes in the ntfs inode and all is done. */
2508                ni->allocated_size = le32_to_cpu(a->length) -
2509                                le16_to_cpu(a->data.resident.value_offset);
2510                /*
2511                 * Note ntfs_resident_attr_value_resize() has already done any
2512                 * necessary data clearing in the attribute record.  When the
2513                 * file is being shrunk vmtruncate() will already have cleared
2514                 * the top part of the last partial page, i.e. since this is
2515                 * the resident case this is the page with index 0.  However,
2516                 * when the file is being expanded, the page cache page data
2517                 * between the old data_size, i.e. old_size, and the new_size
2518                 * has not been zeroed.  Fortunately, we do not need to zero it
2519                 * either since on one hand it will either already be zero due
2520                 * to both readpage and writepage clearing partial page data
2521                 * beyond i_size in which case there is nothing to do or in the
2522                 * case of the file being mmap()ped at the same time, POSIX
2523                 * specifies that the behaviour is unspecified thus we do not
2524                 * have to do anything.  This means that in our implementation
2525                 * in the rare case that the file is mmap()ped and a write
2526                 * occurred into the mmap()ped region just beyond the file size
2527                 * and writepage has not yet been called to write out the page
2528                 * (which would clear the area beyond the file size) and we now
2529                 * extend the file size to incorporate this dirty region
2530                 * outside the file size, a write of the page would result in
2531                 * this data being written to disk instead of being cleared.
2532                 * Given both POSIX and the Linux mmap(2) man page specify that
2533                 * this corner case is undefined, we choose to leave it like
2534                 * that as this is much simpler for us as we cannot lock the
2535                 * relevant page now since we are holding too many ntfs locks
2536                 * which would result in a lock reversal deadlock.
2537                 */
2538                ni->initialized_size = new_size;
2539                write_unlock_irqrestore(&ni->size_lock, flags);
2540                goto unm_done;
2541        }
2542        /* If the above resize failed, this must be an attribute extension. */
2543        BUG_ON(size_change < 0);
2544        /*
2545         * We have to drop all the locks so we can call
2546         * ntfs_attr_make_non_resident().  This could be optimised by try-
2547         * locking the first page cache page and only if that fails dropping
2548         * the locks, locking the page, and redoing all the locking and
2549         * lookups.  While this would be a huge optimisation, it is not worth
2550         * it as this is definitely a slow code path as it only ever can happen
2551         * once for any given file.
2552         */
2553        ntfs_attr_put_search_ctx(ctx);
2554        unmap_mft_record(base_ni);
2555        up_write(&ni->runlist.lock);
2556        /*
2557         * Not enough space in the mft record, try to make the attribute
2558         * non-resident and if successful restart the truncation process.
2559         */
2560        err = ntfs_attr_make_non_resident(ni, old_size);
2561        if (likely(!err))
2562                goto retry_truncate;
2563        /*
2564         * Could not make non-resident.  If this is due to this not being
2565         * permitted for this attribute type or there not being enough space,
2566         * try to make other attributes non-resident.  Otherwise fail.
2567         */
2568        if (unlikely(err != -EPERM && err != -ENOSPC)) {
2569                ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, attribute "
2570                                "type 0x%x, because the conversion from "
2571                                "resident to non-resident attribute failed "
2572                                "with error code %i.", vi->i_ino,
2573                                (unsigned)le32_to_cpu(ni->type), err);
2574                if (err != -ENOMEM)
2575                        err = -EIO;
2576                goto conv_err_out;
2577        }
2578        /* TODO: Not implemented from here, abort. */
2579        if (err == -ENOSPC)
2580                ntfs_error(vol->sb, "Not enough space in the mft record/on "
2581                                "disk for the non-resident attribute value.  "
2582                                "This case is not implemented yet.");
2583        else /* if (err == -EPERM) */
2584                ntfs_error(vol->sb, "This attribute type may not be "
2585                                "non-resident.  This case is not implemented "
2586                                "yet.");
2587        err = -EOPNOTSUPP;
2588        goto conv_err_out;
2589#if 0
2590        // TODO: Attempt to make other attributes non-resident.
2591        if (!err)
2592                goto do_resident_extend;
2593        /*
2594         * Both the attribute list attribute and the standard information
2595         * attribute must remain in the base inode.  Thus, if this is one of
2596         * these attributes, we have to try to move other attributes out into
2597         * extent mft records instead.
2598         */
2599        if (ni->type == AT_ATTRIBUTE_LIST ||
2600                        ni->type == AT_STANDARD_INFORMATION) {
2601                // TODO: Attempt to move other attributes into extent mft
2602                // records.
2603                err = -EOPNOTSUPP;
2604                if (!err)
2605                        goto do_resident_extend;
2606                goto err_out;
2607        }
2608        // TODO: Attempt to move this attribute to an extent mft record, but
2609        // only if it is not already the only attribute in an mft record in
2610        // which case there would be nothing to gain.
2611        err = -EOPNOTSUPP;
2612        if (!err)
2613                goto do_resident_extend;
2614        /* There is nothing we can do to make enough space. )-: */
2615        goto err_out;
2616#endif
2617do_non_resident_truncate:
2618        BUG_ON(!NInoNonResident(ni));
2619        if (alloc_change < 0) {
2620                highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
2621                if (highest_vcn > 0 &&
2622                                old_alloc_size >> vol->cluster_size_bits >
2623                                highest_vcn + 1) {
2624                        /*
2625                         * This attribute has multiple extents.  Not yet
2626                         * supported.
2627                         */
2628                        ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, "
2629                                        "attribute type 0x%x, because the "
2630                                        "attribute is highly fragmented (it "
2631                                        "consists of multiple extents) and "
2632                                        "this case is not implemented yet.",
2633                                        vi->i_ino,
2634                                        (unsigned)le32_to_cpu(ni->type));
2635                        err = -EOPNOTSUPP;
2636                        goto bad_out;
2637                }
2638        }
2639        /*
2640         * If the size is shrinking, need to reduce the initialized_size and
2641         * the data_size before reducing the allocation.
2642         */
2643        if (size_change < 0) {
2644                /*
2645                 * Make the valid size smaller (i_size is already up-to-date).
2646                 */
2647                write_lock_irqsave(&ni->size_lock, flags);
2648                if (new_size < ni->initialized_size) {
2649                        ni->initialized_size = new_size;
2650                        a->data.non_resident.initialized_size =
2651                                        cpu_to_sle64(new_size);
2652                }
2653                a->data.non_resident.data_size = cpu_to_sle64(new_size);
2654                write_unlock_irqrestore(&ni->size_lock, flags);
2655                flush_dcache_mft_record_page(ctx->ntfs_ino);
2656                mark_mft_record_dirty(ctx->ntfs_ino);
2657                /* If the allocated size is not changing, we are done. */
2658                if (!alloc_change)
2659                        goto unm_done;
2660                /*
2661                 * If the size is shrinking it makes no sense for the
2662                 * allocation to be growing.
2663                 */
2664                BUG_ON(alloc_change > 0);
2665        } else /* if (size_change >= 0) */ {
2666                /*
2667                 * The file size is growing or staying the same but the
2668                 * allocation can be shrinking, growing or staying the same.
2669                 */
2670                if (alloc_change > 0) {
2671                        /*
2672                         * We need to extend the allocation and possibly update
2673                         * the data size.  If we are updating the data size,
2674                         * since we are not touching the initialized_size we do
2675                         * not need to worry about the actual data on disk.
2676                         * And as far as the page cache is concerned, there
2677                         * will be no pages beyond the old data size and any
2678                         * partial region in the last page between the old and
2679                         * new data size (or the end of the page if the new
2680                         * data size is outside the page) does not need to be
2681                         * modified as explained above for the resident
2682                         * attribute truncate case.  To do this, we simply drop
2683                         * the locks we hold and leave all the work to our
2684                         * friendly helper ntfs_attr_extend_allocation().
2685                         */
2686                        ntfs_attr_put_search_ctx(ctx);
2687                        unmap_mft_record(base_ni);
2688                        up_write(&ni->runlist.lock);
2689                        err = ntfs_attr_extend_allocation(ni, new_size,
2690                                        size_change > 0 ? new_size : -1, -1);
2691                        /*
2692                         * ntfs_attr_extend_allocation() will have done error
2693                         * output already.
2694                         */
2695                        goto done;
2696                }
2697                if (!alloc_change)
2698                        goto alloc_done;
2699        }
2700        /* alloc_change < 0 */
2701        /* Free the clusters. */
2702        nr_freed = ntfs_cluster_free(ni, new_alloc_size >>
2703                        vol->cluster_size_bits, -1, ctx);
2704        m = ctx->mrec;
2705        a = ctx->attr;
2706        if (unlikely(nr_freed < 0)) {
2707                ntfs_error(vol->sb, "Failed to release cluster(s) (error code "
2708                                "%lli).  Unmount and run chkdsk to recover "
2709                                "the lost cluster(s).", (long long)nr_freed);
2710                NVolSetErrors(vol);
2711                nr_freed = 0;
2712        }
2713        /* Truncate the runlist. */
2714        err = ntfs_rl_truncate_nolock(vol, &ni->runlist,
2715                        new_alloc_size >> vol->cluster_size_bits);
2716        /*
2717         * If the runlist truncation failed and/or the search context is no
2718         * longer valid, we cannot resize the attribute record or build the
2719         * mapping pairs array thus we mark the inode bad so that no access to
2720         * the freed clusters can happen.
2721         */
2722        if (unlikely(err || IS_ERR(m))) {
2723                ntfs_error(vol->sb, "Failed to %s (error code %li).%s",
2724                                IS_ERR(m) ?
2725                                "restore attribute search context" :
2726                                "truncate attribute runlist",
2727                                IS_ERR(m) ? PTR_ERR(m) : err, es);
2728                err = -EIO;
2729                goto bad_out;
2730        }
2731        /* Get the size for the shrunk mapping pairs array for the runlist. */
2732        mp_size = ntfs_get_size_for_mapping_pairs(vol, ni->runlist.rl, 0, -1);
2733        if (unlikely(mp_size <= 0)) {
2734                ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2735                                "attribute type 0x%x, because determining the "
2736                                "size for the mapping pairs failed with error "
2737                                "code %i.%s", vi->i_ino,
2738                                (unsigned)le32_to_cpu(ni->type), mp_size, es);
2739                err = -EIO;
2740                goto bad_out;
2741        }
2742        /*
2743         * Shrink the attribute record for the new mapping pairs array.  Note,
2744         * this cannot fail since we are making the attribute smaller thus by
2745         * definition there is enough space to do so.
2746         */
2747        attr_len = le32_to_cpu(a->length);
2748        err = ntfs_attr_record_resize(m, a, mp_size +
2749                        le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
2750        BUG_ON(err);
2751        /*
2752         * Generate the mapping pairs array directly into the attribute record.
2753         */
2754        err = ntfs_mapping_pairs_build(vol, (u8*)a +
2755                        le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
2756                        mp_size, ni->runlist.rl, 0, -1, NULL);
2757        if (unlikely(err)) {
2758                ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
2759                                "attribute type 0x%x, because building the "
2760                                "mapping pairs failed with error code %i.%s",
2761                                vi->i_ino, (unsigned)le32_to_cpu(ni->type),
2762                                err, es);
2763                err = -EIO;
2764                goto bad_out;
2765        }
2766        /* Update the allocated/compressed size as well as the highest vcn. */
2767        a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >>
2768                        vol->cluster_size_bits) - 1);
2769        write_lock_irqsave(&ni->size_lock, flags);
2770        ni->allocated_size = new_alloc_size;
2771        a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size);
2772        if (NInoSparse(ni) || NInoCompressed(ni)) {
2773                if (nr_freed) {
2774                        ni->itype.compressed.size -= nr_freed <<
2775                                        vol->cluster_size_bits;
2776                        BUG_ON(ni->itype.compressed.size < 0);
2777                        a->data.non_resident.compressed_size = cpu_to_sle64(
2778                                        ni->itype.compressed.size);
2779                        vi->i_blocks = ni->itype.compressed.size >> 9;
2780                }
2781        } else
2782                vi->i_blocks = new_alloc_size >> 9;
2783        write_unlock_irqrestore(&ni->size_lock, flags);
2784        /*
2785         * We have shrunk the allocation.  If this is a shrinking truncate we
2786         * have already dealt with the initialized_size and the data_size above
2787         * and we are done.  If the truncate is only changing the allocation
2788         * and not the data_size, we are also done.  If this is an extending
2789         * truncate, need to extend the data_size now which is ensured by the
2790         * fact that @size_change is positive.
2791         */
2792alloc_done:
2793        /*
2794         * If the size is growing, need to update it now.  If it is shrinking,
2795         * we have already updated it above (before the allocation change).
2796         */
2797        if (size_change > 0)
2798                a->data.non_resident.data_size = cpu_to_sle64(new_size);
2799        /* Ensure the modified mft record is written out. */
2800        flush_dcache_mft_record_page(ctx->ntfs_ino);
2801        mark_mft_record_dirty(ctx->ntfs_ino);
2802unm_done:
2803        ntfs_attr_put_search_ctx(ctx);
2804        unmap_mft_record(base_ni);
2805        up_write(&ni->runlist.lock);
2806done:
2807        /* Update the mtime and ctime on the base inode. */
2808        /* normally ->truncate shouldn't update ctime or mtime,
2809         * but ntfs did before so it got a copy & paste version
2810         * of file_update_time.  one day someone should fix this
2811         * for real.
2812         */
2813        if (!IS_NOCMTIME(VFS_I(base_ni)) && !IS_RDONLY(VFS_I(base_ni))) {
2814                struct timespec now = current_fs_time(VFS_I(base_ni)->i_sb);
2815                int sync_it = 0;
2816
2817                if (!timespec_equal(&VFS_I(base_ni)->i_mtime, &now) ||
2818                    !timespec_equal(&VFS_I(base_ni)->i_ctime, &now))
2819                        sync_it = 1;
2820                VFS_I(base_ni)->i_mtime = now;
2821                VFS_I(base_ni)->i_ctime = now;
2822
2823                if (sync_it)
2824                        mark_inode_dirty_sync(VFS_I(base_ni));
2825        }
2826
2827        if (likely(!err)) {
2828                NInoClearTruncateFailed(ni);
2829                ntfs_debug("Done.");
2830        }
2831        return err;
2832old_bad_out:
2833        old_size = -1;
2834bad_out:
2835        if (err != -ENOMEM && err != -EOPNOTSUPP)
2836                NVolSetErrors(vol);
2837        if (err != -EOPNOTSUPP)
2838                NInoSetTruncateFailed(ni);
2839        else if (old_size >= 0)
2840                i_size_write(vi, old_size);
2841err_out:
2842        if (ctx)
2843                ntfs_attr_put_search_ctx(ctx);
2844        if (m)
2845                unmap_mft_record(base_ni);
2846        up_write(&ni->runlist.lock);
2847out:
2848        ntfs_debug("Failed.  Returning error code %i.", err);
2849        return err;
2850conv_err_out:
2851        if (err != -ENOMEM && err != -EOPNOTSUPP)
2852                NVolSetErrors(vol);
2853        if (err != -EOPNOTSUPP)
2854                NInoSetTruncateFailed(ni);
2855        else
2856                i_size_write(vi, old_size);
2857        goto out;
2858}
2859
2860/**
2861 * ntfs_truncate_vfs - wrapper for ntfs_truncate() that has no return value
2862 * @vi:         inode for which the i_size was changed
2863 *
2864 * Wrapper for ntfs_truncate() that has no return value.
2865 *
2866 * See ntfs_truncate() description above for details.
2867 */
2868void ntfs_truncate_vfs(struct inode *vi) {
2869        ntfs_truncate(vi);
2870}
2871
2872/**
2873 * ntfs_setattr - called from notify_change() when an attribute is being changed
2874 * @dentry:     dentry whose attributes to change
2875 * @attr:       structure describing the attributes and the changes
2876 *
2877 * We have to trap VFS attempts to truncate the file described by @dentry as
2878 * soon as possible, because we do not implement changes in i_size yet.  So we
2879 * abort all i_size changes here.
2880 *
2881 * We also abort all changes of user, group, and mode as we do not implement
2882 * the NTFS ACLs yet.
2883 *
2884 * Called with ->i_mutex held.
2885 */
2886int ntfs_setattr(struct dentry *dentry, struct iattr *attr)
2887{
2888        struct inode *vi = dentry->d_inode;
2889        int err;
2890        unsigned int ia_valid = attr->ia_valid;
2891
2892        err = inode_change_ok(vi, attr);
2893        if (err)
2894                goto out;
2895        /* We do not support NTFS ACLs yet. */
2896        if (ia_valid & (ATTR_UID | ATTR_GID | ATTR_MODE)) {
2897                ntfs_warning(vi->i_sb, "Changes in user/group/mode are not "
2898                                "supported yet, ignoring.");
2899                err = -EOPNOTSUPP;
2900                goto out;
2901        }
2902        if (ia_valid & ATTR_SIZE) {
2903                if (attr->ia_size != i_size_read(vi)) {
2904                        ntfs_inode *ni = NTFS_I(vi);
2905                        /*
2906                         * FIXME: For now we do not support resizing of
2907                         * compressed or encrypted files yet.
2908                         */
2909                        if (NInoCompressed(ni) || NInoEncrypted(ni)) {
2910                                ntfs_warning(vi->i_sb, "Changes in inode size "
2911                                                "are not supported yet for "
2912                                                "%s files, ignoring.",
2913                                                NInoCompressed(ni) ?
2914                                                "compressed" : "encrypted");
2915                                err = -EOPNOTSUPP;
2916                        } else
2917                                err = vmtruncate(vi, attr->ia_size);
2918                        if (err || ia_valid == ATTR_SIZE)
2919                                goto out;
2920                } else {
2921                        /*
2922                         * We skipped the truncate but must still update
2923                         * timestamps.
2924                         */
2925                        ia_valid |= ATTR_MTIME | ATTR_CTIME;
2926                }
2927        }
2928        if (ia_valid & ATTR_ATIME)
2929                vi->i_atime = timespec_trunc(attr->ia_atime,
2930                                vi->i_sb->s_time_gran);
2931        if (ia_valid & ATTR_MTIME)
2932                vi->i_mtime = timespec_trunc(attr->ia_mtime,
2933                                vi->i_sb->s_time_gran);
2934        if (ia_valid & ATTR_CTIME)
2935                vi->i_ctime = timespec_trunc(attr->ia_ctime,
2936                                vi->i_sb->s_time_gran);
2937        mark_inode_dirty(vi);
2938out:
2939        return err;
2940}
2941
2942/**
2943 * ntfs_write_inode - write out a dirty inode
2944 * @vi:         inode to write out
2945 * @sync:       if true, write out synchronously
2946 *
2947 * Write out a dirty inode to disk including any extent inodes if present.
2948 *
2949 * If @sync is true, commit the inode to disk and wait for io completion.  This
2950 * is done using write_mft_record().
2951 *
2952 * If @sync is false, just schedule the write to happen but do not wait for i/o
2953 * completion.  In 2.6 kernels, scheduling usually happens just by virtue of
2954 * marking the page (and in this case mft record) dirty but we do not implement
2955 * this yet as write_mft_record() largely ignores the @sync parameter and
2956 * always performs synchronous writes.
2957 *
2958 * Return 0 on success and -errno on error.
2959 */
2960int __ntfs_write_inode(struct inode *vi, int sync)
2961{
2962        sle64 nt;
2963        ntfs_inode *ni = NTFS_I(vi);
2964        ntfs_attr_search_ctx *ctx;
2965        MFT_RECORD *m;
2966        STANDARD_INFORMATION *si;
2967        int err = 0;
2968        bool modified = false;
2969
2970        ntfs_debug("Entering for %sinode 0x%lx.", NInoAttr(ni) ? "attr " : "",
2971                        vi->i_ino);
2972        /*
2973         * Dirty attribute inodes are written via their real inodes so just
2974         * clean them here.  Access time updates are taken care off when the
2975         * real inode is written.
2976         */
2977        if (NInoAttr(ni)) {
2978                NInoClearDirty(ni);
2979                ntfs_debug("Done.");
2980                return 0;
2981        }
2982        /* Map, pin, and lock the mft record belonging to the inode. */
2983        m = map_mft_record(ni);
2984        if (IS_ERR(m)) {
2985                err = PTR_ERR(m);
2986                goto err_out;
2987        }
2988        /* Update the access times in the standard information attribute. */
2989        ctx = ntfs_attr_get_search_ctx(ni, m);
2990        if (unlikely(!ctx)) {
2991                err = -ENOMEM;
2992                goto unm_err_out;
2993        }
2994        err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0,
2995                        CASE_SENSITIVE, 0, NULL, 0, ctx);
2996        if (unlikely(err)) {
2997                ntfs_attr_put_search_ctx(ctx);
2998                goto unm_err_out;
2999        }
3000        si = (STANDARD_INFORMATION*)((u8*)ctx->attr +
3001                        le16_to_cpu(ctx->attr->data.resident.value_offset));
3002        /* Update the access times if they have changed. */
3003        nt = utc2ntfs(vi->i_mtime);
3004        if (si->last_data_change_time != nt) {
3005                ntfs_debug("Updating mtime for inode 0x%lx: old = 0x%llx, "
3006                                "new = 0x%llx", vi->i_ino, (long long)
3007                                sle64_to_cpu(si->last_data_change_time),
3008                                (long long)sle64_to_cpu(nt));
3009                si->last_data_change_time = nt;
3010                modified = true;
3011        }
3012        nt = utc2ntfs(vi->i_ctime);
3013        if (si->last_mft_change_time != nt) {
3014                ntfs_debug("Updating ctime for inode 0x%lx: old = 0x%llx, "
3015                                "new = 0x%llx", vi->i_ino, (long long)
3016                                sle64_to_cpu(si->last_mft_change_time),
3017                                (long long)sle64_to_cpu(nt));
3018                si->last_mft_change_time = nt;
3019                modified = true;
3020        }
3021        nt = utc2ntfs(vi->i_atime);
3022        if (si->last_access_time != nt) {
3023                ntfs_debug("Updating atime for inode 0x%lx: old = 0x%llx, "
3024                                "new = 0x%llx", vi->i_ino,
3025                                (long long)sle64_to_cpu(si->last_access_time),
3026                                (long long)sle64_to_cpu(nt));
3027                si->last_access_time = nt;
3028                modified = true;
3029        }
3030        /*
3031         * If we just modified the standard information attribute we need to
3032         * mark the mft record it is in dirty.  We do this manually so that
3033         * mark_inode_dirty() is not called which would redirty the inode and
3034         * hence result in an infinite loop of trying to write the inode.
3035         * There is no need to mark the base inode nor the base mft record
3036         * dirty, since we are going to write this mft record below in any case
3037         * and the base mft record may actually not have been modified so it
3038         * might not need to be written out.
3039         * NOTE: It is not a problem when the inode for $MFT itself is being
3040         * written out as mark_ntfs_record_dirty() will only set I_DIRTY_PAGES
3041         * on the $MFT inode and hence ntfs_write_inode() will not be
3042         * re-invoked because of it which in turn is ok since the dirtied mft
3043         * record will be cleaned and written out to disk below, i.e. before
3044         * this function returns.
3045         */
3046        if (modified) {
3047                flush_dcache_mft_record_page(ctx->ntfs_ino);
3048                if (!NInoTestSetDirty(ctx->ntfs_ino))
3049                        mark_ntfs_record_dirty(ctx->ntfs_ino->page,
3050                                        ctx->ntfs_ino->page_ofs);
3051        }
3052        ntfs_attr_put_search_ctx(ctx);
3053        /* Now the access times are updated, write the base mft record. */
3054        if (NInoDirty(ni))
3055                err = write_mft_record(ni, m, sync);
3056        /* Write all attached extent mft records. */
3057        mutex_lock(&ni->extent_lock);
3058        if (ni->nr_extents > 0) {
3059                ntfs_inode **extent_nis = ni->ext.extent_ntfs_inos;
3060                int i;
3061
3062                ntfs_debug("Writing %i extent inodes.", ni->nr_extents);
3063                for (i = 0; i < ni->nr_extents; i++) {
3064                        ntfs_inode *tni = extent_nis[i];
3065
3066                        if (NInoDirty(tni)) {
3067                                MFT_RECORD *tm = map_mft_record(tni);
3068                                int ret;
3069
3070                                if (IS_ERR(tm)) {
3071                                        if (!err || err == -ENOMEM)
3072                                                err = PTR_ERR(tm);
3073                                        continue;
3074                                }
3075                                ret = write_mft_record(tni, tm, sync);
3076                                unmap_mft_record(tni);
3077                                if (unlikely(ret)) {
3078                                        if (!err || err == -ENOMEM)
3079                                                err = ret;
3080                                }
3081                        }
3082                }
3083        }
3084        mutex_unlock(&ni->extent_lock);
3085        unmap_mft_record(ni);
3086        if (unlikely(err))
3087                goto err_out;
3088        ntfs_debug("Done.");
3089        return 0;
3090unm_err_out:
3091        unmap_mft_record(ni);
3092err_out:
3093        if (err == -ENOMEM) {
3094                ntfs_warning(vi->i_sb, "Not enough memory to write inode.  "
3095                                "Marking the inode dirty again, so the VFS "
3096                                "retries later.");
3097                mark_inode_dirty(vi);
3098        } else {
3099                ntfs_error(vi->i_sb, "Failed (error %i):  Run chkdsk.", -err);
3100                NVolSetErrors(ni->vol);
3101        }
3102        return err;
3103}
3104
3105#endif /* NTFS_RW */
3106
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