Logo Search packages:      
Sourcecode: linux-2.6 version File versions  Download package

inode.c

/**
 * inode.c - NTFS kernel inode handling. Part of the Linux-NTFS project.
 *
 * Copyright (c) 2001-2006 Anton Altaparmakov
 *
 * This program/include file is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program/include file is distributed in the hope that it will be
 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program (in the main directory of the Linux-NTFS
 * distribution in the file COPYING); if not, write to the Free Software
 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include <linux/buffer_head.h>
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/mount.h>
#include <linux/mutex.h>
#include <linux/pagemap.h>
#include <linux/quotaops.h>
#include <linux/slab.h>
#include <linux/smp_lock.h>

#include "aops.h"
#include "attrib.h"
#include "bitmap.h"
#include "dir.h"
#include "debug.h"
#include "inode.h"
#include "attrib.h"
#include "lcnalloc.h"
#include "malloc.h"
#include "mft.h"
#include "time.h"
#include "ntfs.h"

/**
 * ntfs_test_inode - compare two (possibly fake) inodes for equality
 * @vi:           vfs inode which to test
 * @na:           ntfs attribute which is being tested with
 *
 * Compare the ntfs attribute embedded in the ntfs specific part of the vfs
 * inode @vi for equality with the ntfs attribute @na.
 *
 * If searching for the normal file/directory inode, set @na->type to AT_UNUSED.
 * @na->name and @na->name_len are then ignored.
 *
 * Return 1 if the attributes match and 0 if not.
 *
 * NOTE: This function runs with the inode_lock spin lock held so it is not
 * allowed to sleep.
 */
int ntfs_test_inode(struct inode *vi, ntfs_attr *na)
{
      ntfs_inode *ni;

      if (vi->i_ino != na->mft_no)
            return 0;
      ni = NTFS_I(vi);
      /* If !NInoAttr(ni), @vi is a normal file or directory inode. */
      if (likely(!NInoAttr(ni))) {
            /* If not looking for a normal inode this is a mismatch. */
            if (unlikely(na->type != AT_UNUSED))
                  return 0;
      } else {
            /* A fake inode describing an attribute. */
            if (ni->type != na->type)
                  return 0;
            if (ni->name_len != na->name_len)
                  return 0;
            if (na->name_len && memcmp(ni->name, na->name,
                        na->name_len * sizeof(ntfschar)))
                  return 0;
      }
      /* Match! */
      return 1;
}

/**
 * ntfs_init_locked_inode - initialize an inode
 * @vi:           vfs inode to initialize
 * @na:           ntfs attribute which to initialize @vi to
 *
 * Initialize the vfs inode @vi with the values from the ntfs attribute @na in
 * order to enable ntfs_test_inode() to do its work.
 *
 * If initializing the normal file/directory inode, set @na->type to AT_UNUSED.
 * In that case, @na->name and @na->name_len should be set to NULL and 0,
 * respectively. Although that is not strictly necessary as
 * ntfs_read_inode_locked() will fill them in later.
 *
 * Return 0 on success and -errno on error.
 *
 * NOTE: This function runs with the inode_lock spin lock held so it is not
 * allowed to sleep. (Hence the GFP_ATOMIC allocation.)
 */
static int ntfs_init_locked_inode(struct inode *vi, ntfs_attr *na)
{
      ntfs_inode *ni = NTFS_I(vi);

      vi->i_ino = na->mft_no;

      ni->type = na->type;
      if (na->type == AT_INDEX_ALLOCATION)
            NInoSetMstProtected(ni);

      ni->name = na->name;
      ni->name_len = na->name_len;

      /* If initializing a normal inode, we are done. */
      if (likely(na->type == AT_UNUSED)) {
            BUG_ON(na->name);
            BUG_ON(na->name_len);
            return 0;
      }

      /* It is a fake inode. */
      NInoSetAttr(ni);

      /*
       * We have I30 global constant as an optimization as it is the name
       * in >99.9% of named attributes! The other <0.1% incur a GFP_ATOMIC
       * allocation but that is ok. And most attributes are unnamed anyway,
       * thus the fraction of named attributes with name != I30 is actually
       * absolutely tiny.
       */
      if (na->name_len && na->name != I30) {
            unsigned int i;

            BUG_ON(!na->name);
            i = na->name_len * sizeof(ntfschar);
            ni->name = (ntfschar*)kmalloc(i + sizeof(ntfschar), GFP_ATOMIC);
            if (!ni->name)
                  return -ENOMEM;
            memcpy(ni->name, na->name, i);
            ni->name[i] = 0;
      }
      return 0;
}

typedef int (*set_t)(struct inode *, void *);
static int ntfs_read_locked_inode(struct inode *vi);
static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi);
static int ntfs_read_locked_index_inode(struct inode *base_vi,
            struct inode *vi);

/**
 * ntfs_iget - obtain a struct inode corresponding to a specific normal inode
 * @sb:           super block of mounted volume
 * @mft_no: mft record number / inode number to obtain
 *
 * Obtain the struct inode corresponding to a specific normal inode (i.e. a
 * file or directory).
 *
 * If the inode is in the cache, it is just returned with an increased
 * reference count. Otherwise, a new struct inode is allocated and initialized,
 * and finally ntfs_read_locked_inode() is called to read in the inode and
 * fill in the remainder of the inode structure.
 *
 * Return the struct inode on success. Check the return value with IS_ERR() and
 * if true, the function failed and the error code is obtained from PTR_ERR().
 */
struct inode *ntfs_iget(struct super_block *sb, unsigned long mft_no)
{
      struct inode *vi;
      ntfs_attr na;
      int err;

      na.mft_no = mft_no;
      na.type = AT_UNUSED;
      na.name = NULL;
      na.name_len = 0;

      vi = iget5_locked(sb, mft_no, (test_t)ntfs_test_inode,
                  (set_t)ntfs_init_locked_inode, &na);
      if (unlikely(!vi))
            return ERR_PTR(-ENOMEM);

      err = 0;

      /* If this is a freshly allocated inode, need to read it now. */
      if (vi->i_state & I_NEW) {
            err = ntfs_read_locked_inode(vi);
            unlock_new_inode(vi);
      }
      /*
       * There is no point in keeping bad inodes around if the failure was
       * due to ENOMEM. We want to be able to retry again later.
       */
      if (unlikely(err == -ENOMEM)) {
            iput(vi);
            vi = ERR_PTR(err);
      }
      return vi;
}

/**
 * ntfs_attr_iget - obtain a struct inode corresponding to an attribute
 * @base_vi:      vfs base inode containing the attribute
 * @type:   attribute type
 * @name:   Unicode name of the attribute (NULL if unnamed)
 * @name_len:     length of @name in Unicode characters (0 if unnamed)
 *
 * Obtain the (fake) struct inode corresponding to the attribute specified by
 * @type, @name, and @name_len, which is present in the base mft record
 * specified by the vfs inode @base_vi.
 *
 * If the attribute inode is in the cache, it is just returned with an
 * increased reference count. Otherwise, a new struct inode is allocated and
 * initialized, and finally ntfs_read_locked_attr_inode() is called to read the
 * attribute and fill in the inode structure.
 *
 * Note, for index allocation attributes, you need to use ntfs_index_iget()
 * instead of ntfs_attr_iget() as working with indices is a lot more complex.
 *
 * Return the struct inode of the attribute inode on success. Check the return
 * value with IS_ERR() and if true, the function failed and the error code is
 * obtained from PTR_ERR().
 */
struct inode *ntfs_attr_iget(struct inode *base_vi, ATTR_TYPE type,
            ntfschar *name, u32 name_len)
{
      struct inode *vi;
      ntfs_attr na;
      int err;

      /* Make sure no one calls ntfs_attr_iget() for indices. */
      BUG_ON(type == AT_INDEX_ALLOCATION);

      na.mft_no = base_vi->i_ino;
      na.type = type;
      na.name = name;
      na.name_len = name_len;

      vi = iget5_locked(base_vi->i_sb, na.mft_no, (test_t)ntfs_test_inode,
                  (set_t)ntfs_init_locked_inode, &na);
      if (unlikely(!vi))
            return ERR_PTR(-ENOMEM);

      err = 0;

      /* If this is a freshly allocated inode, need to read it now. */
      if (vi->i_state & I_NEW) {
            err = ntfs_read_locked_attr_inode(base_vi, vi);
            unlock_new_inode(vi);
      }
      /*
       * There is no point in keeping bad attribute inodes around. This also
       * simplifies things in that we never need to check for bad attribute
       * inodes elsewhere.
       */
      if (unlikely(err)) {
            iput(vi);
            vi = ERR_PTR(err);
      }
      return vi;
}

/**
 * ntfs_index_iget - obtain a struct inode corresponding to an index
 * @base_vi:      vfs base inode containing the index related attributes
 * @name:   Unicode name of the index
 * @name_len:     length of @name in Unicode characters
 *
 * Obtain the (fake) struct inode corresponding to the index specified by @name
 * and @name_len, which is present in the base mft record specified by the vfs
 * inode @base_vi.
 *
 * If the index inode is in the cache, it is just returned with an increased
 * reference count.  Otherwise, a new struct inode is allocated and
 * initialized, and finally ntfs_read_locked_index_inode() is called to read
 * the index related attributes and fill in the inode structure.
 *
 * Return the struct inode of the index inode on success. Check the return
 * value with IS_ERR() and if true, the function failed and the error code is
 * obtained from PTR_ERR().
 */
struct inode *ntfs_index_iget(struct inode *base_vi, ntfschar *name,
            u32 name_len)
{
      struct inode *vi;
      ntfs_attr na;
      int err;

      na.mft_no = base_vi->i_ino;
      na.type = AT_INDEX_ALLOCATION;
      na.name = name;
      na.name_len = name_len;

      vi = iget5_locked(base_vi->i_sb, na.mft_no, (test_t)ntfs_test_inode,
                  (set_t)ntfs_init_locked_inode, &na);
      if (unlikely(!vi))
            return ERR_PTR(-ENOMEM);

      err = 0;

      /* If this is a freshly allocated inode, need to read it now. */
      if (vi->i_state & I_NEW) {
            err = ntfs_read_locked_index_inode(base_vi, vi);
            unlock_new_inode(vi);
      }
      /*
       * There is no point in keeping bad index inodes around.  This also
       * simplifies things in that we never need to check for bad index
       * inodes elsewhere.
       */
      if (unlikely(err)) {
            iput(vi);
            vi = ERR_PTR(err);
      }
      return vi;
}

struct inode *ntfs_alloc_big_inode(struct super_block *sb)
{
      ntfs_inode *ni;

      ntfs_debug("Entering.");
      ni = kmem_cache_alloc(ntfs_big_inode_cache, SLAB_NOFS);
      if (likely(ni != NULL)) {
            ni->state = 0;
            return VFS_I(ni);
      }
      ntfs_error(sb, "Allocation of NTFS big inode structure failed.");
      return NULL;
}

void ntfs_destroy_big_inode(struct inode *inode)
{
      ntfs_inode *ni = NTFS_I(inode);

      ntfs_debug("Entering.");
      BUG_ON(ni->page);
      if (!atomic_dec_and_test(&ni->count))
            BUG();
      kmem_cache_free(ntfs_big_inode_cache, NTFS_I(inode));
}

static inline ntfs_inode *ntfs_alloc_extent_inode(void)
{
      ntfs_inode *ni;

      ntfs_debug("Entering.");
      ni = kmem_cache_alloc(ntfs_inode_cache, SLAB_NOFS);
      if (likely(ni != NULL)) {
            ni->state = 0;
            return ni;
      }
      ntfs_error(NULL, "Allocation of NTFS inode structure failed.");
      return NULL;
}

static void ntfs_destroy_extent_inode(ntfs_inode *ni)
{
      ntfs_debug("Entering.");
      BUG_ON(ni->page);
      if (!atomic_dec_and_test(&ni->count))
            BUG();
      kmem_cache_free(ntfs_inode_cache, ni);
}

/*
 * The attribute runlist lock has separate locking rules from the
 * normal runlist lock, so split the two lock-classes:
 */
static struct lock_class_key attr_list_rl_lock_class;

/**
 * __ntfs_init_inode - initialize ntfs specific part of an inode
 * @sb:           super block of mounted volume
 * @ni:           freshly allocated ntfs inode which to initialize
 *
 * Initialize an ntfs inode to defaults.
 *
 * NOTE: ni->mft_no, ni->state, ni->type, ni->name, and ni->name_len are left
 * untouched. Make sure to initialize them elsewhere.
 *
 * Return zero on success and -ENOMEM on error.
 */
void __ntfs_init_inode(struct super_block *sb, ntfs_inode *ni)
{
      ntfs_debug("Entering.");
      rwlock_init(&ni->size_lock);
      ni->initialized_size = ni->allocated_size = 0;
      ni->seq_no = 0;
      atomic_set(&ni->count, 1);
      ni->vol = NTFS_SB(sb);
      ntfs_init_runlist(&ni->runlist);
      mutex_init(&ni->mrec_lock);
      ni->page = NULL;
      ni->page_ofs = 0;
      ni->attr_list_size = 0;
      ni->attr_list = NULL;
      ntfs_init_runlist(&ni->attr_list_rl);
      lockdep_set_class(&ni->attr_list_rl.lock,
                        &attr_list_rl_lock_class);
      ni->itype.index.bmp_ino = NULL;
      ni->itype.index.block_size = 0;
      ni->itype.index.vcn_size = 0;
      ni->itype.index.collation_rule = 0;
      ni->itype.index.block_size_bits = 0;
      ni->itype.index.vcn_size_bits = 0;
      mutex_init(&ni->extent_lock);
      ni->nr_extents = 0;
      ni->ext.base_ntfs_ino = NULL;
}

/*
 * Extent inodes get MFT-mapped in a nested way, while the base inode
 * is still mapped. Teach this nesting to the lock validator by creating
 * a separate class for nested inode's mrec_lock's:
 */
static struct lock_class_key extent_inode_mrec_lock_key;

inline ntfs_inode *ntfs_new_extent_inode(struct super_block *sb,
            unsigned long mft_no)
{
      ntfs_inode *ni = ntfs_alloc_extent_inode();

      ntfs_debug("Entering.");
      if (likely(ni != NULL)) {
            __ntfs_init_inode(sb, ni);
            lockdep_set_class(&ni->mrec_lock, &extent_inode_mrec_lock_key);
            ni->mft_no = mft_no;
            ni->type = AT_UNUSED;
            ni->name = NULL;
            ni->name_len = 0;
      }
      return ni;
}

/**
 * ntfs_is_extended_system_file - check if a file is in the $Extend directory
 * @ctx:    initialized attribute search context
 *
 * Search all file name attributes in the inode described by the attribute
 * search context @ctx and check if any of the names are in the $Extend system
 * directory.
 *
 * Return values:
 *       1: file is in $Extend directory
 *       0: file is not in $Extend directory
 *    -errno: failed to determine if the file is in the $Extend directory
 */
static int ntfs_is_extended_system_file(ntfs_attr_search_ctx *ctx)
{
      int nr_links, err;

      /* Restart search. */
      ntfs_attr_reinit_search_ctx(ctx);

      /* Get number of hard links. */
      nr_links = le16_to_cpu(ctx->mrec->link_count);

      /* Loop through all hard links. */
      while (!(err = ntfs_attr_lookup(AT_FILE_NAME, NULL, 0, 0, 0, NULL, 0,
                  ctx))) {
            FILE_NAME_ATTR *file_name_attr;
            ATTR_RECORD *attr = ctx->attr;
            u8 *p, *p2;

            nr_links--;
            /*
             * Maximum sanity checking as we are called on an inode that
             * we suspect might be corrupt.
             */
            p = (u8*)attr + le32_to_cpu(attr->length);
            if (p < (u8*)ctx->mrec || (u8*)p > (u8*)ctx->mrec +
                        le32_to_cpu(ctx->mrec->bytes_in_use)) {
err_corrupt_attr:
                  ntfs_error(ctx->ntfs_ino->vol->sb, "Corrupt file name "
                              "attribute. You should run chkdsk.");
                  return -EIO;
            }
            if (attr->non_resident) {
                  ntfs_error(ctx->ntfs_ino->vol->sb, "Non-resident file "
                              "name. You should run chkdsk.");
                  return -EIO;
            }
            if (attr->flags) {
                  ntfs_error(ctx->ntfs_ino->vol->sb, "File name with "
                              "invalid flags. You should run "
                              "chkdsk.");
                  return -EIO;
            }
            if (!(attr->data.resident.flags & RESIDENT_ATTR_IS_INDEXED)) {
                  ntfs_error(ctx->ntfs_ino->vol->sb, "Unindexed file "
                              "name. You should run chkdsk.");
                  return -EIO;
            }
            file_name_attr = (FILE_NAME_ATTR*)((u8*)attr +
                        le16_to_cpu(attr->data.resident.value_offset));
            p2 = (u8*)attr + le32_to_cpu(attr->data.resident.value_length);
            if (p2 < (u8*)attr || p2 > p)
                  goto err_corrupt_attr;
            /* This attribute is ok, but is it in the $Extend directory? */
            if (MREF_LE(file_name_attr->parent_directory) == FILE_Extend)
                  return 1;   /* YES, it's an extended system file. */
      }
      if (unlikely(err != -ENOENT))
            return err;
      if (unlikely(nr_links)) {
            ntfs_error(ctx->ntfs_ino->vol->sb, "Inode hard link count "
                        "doesn't match number of name attributes. You "
                        "should run chkdsk.");
            return -EIO;
      }
      return 0;   /* NO, it is not an extended system file. */
}

/**
 * ntfs_read_locked_inode - read an inode from its device
 * @vi:           inode to read
 *
 * ntfs_read_locked_inode() is called from ntfs_iget() to read the inode
 * described by @vi into memory from the device.
 *
 * The only fields in @vi that we need to/can look at when the function is
 * called are i_sb, pointing to the mounted device's super block, and i_ino,
 * the number of the inode to load.
 *
 * ntfs_read_locked_inode() maps, pins and locks the mft record number i_ino
 * for reading and sets up the necessary @vi fields as well as initializing
 * the ntfs inode.
 *
 * Q: What locks are held when the function is called?
 * A: i_state has I_LOCK set, hence the inode is locked, also
 *    i_count is set to 1, so it is not going to go away
 *    i_flags is set to 0 and we have no business touching it.  Only an ioctl()
 *    is allowed to write to them. We should of course be honouring them but
 *    we need to do that using the IS_* macros defined in include/linux/fs.h.
 *    In any case ntfs_read_locked_inode() has nothing to do with i_flags.
 *
 * Return 0 on success and -errno on error.  In the error case, the inode will
 * have had make_bad_inode() executed on it.
 */
static int ntfs_read_locked_inode(struct inode *vi)
{
      ntfs_volume *vol = NTFS_SB(vi->i_sb);
      ntfs_inode *ni;
      MFT_RECORD *m;
      ATTR_RECORD *a;
      STANDARD_INFORMATION *si;
      ntfs_attr_search_ctx *ctx;
      int err = 0;

      ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);

      /* Setup the generic vfs inode parts now. */

      /* This is the optimal IO size (for stat), not the fs block size. */
      vi->i_blksize = PAGE_CACHE_SIZE;
      /*
       * This is for checking whether an inode has changed w.r.t. a file so
       * that the file can be updated if necessary (compare with f_version).
       */
      vi->i_version = 1;

      vi->i_uid = vol->uid;
      vi->i_gid = vol->gid;
      vi->i_mode = 0;

      /*
       * Initialize the ntfs specific part of @vi special casing
       * FILE_MFT which we need to do at mount time.
       */
      if (vi->i_ino != FILE_MFT)
            ntfs_init_big_inode(vi);
      ni = NTFS_I(vi);

      m = map_mft_record(ni);
      if (IS_ERR(m)) {
            err = PTR_ERR(m);
            goto err_out;
      }
      ctx = ntfs_attr_get_search_ctx(ni, m);
      if (!ctx) {
            err = -ENOMEM;
            goto unm_err_out;
      }

      if (!(m->flags & MFT_RECORD_IN_USE)) {
            ntfs_error(vi->i_sb, "Inode is not in use!");
            goto unm_err_out;
      }
      if (m->base_mft_record) {
            ntfs_error(vi->i_sb, "Inode is an extent inode!");
            goto unm_err_out;
      }

      /* Transfer information from mft record into vfs and ntfs inodes. */
      vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);

      /*
       * FIXME: Keep in mind that link_count is two for files which have both
       * a long file name and a short file name as separate entries, so if
       * we are hiding short file names this will be too high. Either we need
       * to account for the short file names by subtracting them or we need
       * to make sure we delete files even though i_nlink is not zero which
       * might be tricky due to vfs interactions. Need to think about this
       * some more when implementing the unlink command.
       */
      vi->i_nlink = le16_to_cpu(m->link_count);
      /*
       * FIXME: Reparse points can have the directory bit set even though
       * they would be S_IFLNK. Need to deal with this further below when we
       * implement reparse points / symbolic links but it will do for now.
       * Also if not a directory, it could be something else, rather than
       * a regular file. But again, will do for now.
       */
      /* Everyone gets all permissions. */
      vi->i_mode |= S_IRWXUGO;
      /* If read-only, noone gets write permissions. */
      if (IS_RDONLY(vi))
            vi->i_mode &= ~S_IWUGO;
      if (m->flags & MFT_RECORD_IS_DIRECTORY) {
            vi->i_mode |= S_IFDIR;
            /*
             * Apply the directory permissions mask set in the mount
             * options.
             */
            vi->i_mode &= ~vol->dmask;
            /* Things break without this kludge! */
            if (vi->i_nlink > 1)
                  vi->i_nlink = 1;
      } else {
            vi->i_mode |= S_IFREG;
            /* Apply the file permissions mask set in the mount options. */
            vi->i_mode &= ~vol->fmask;
      }
      /*
       * Find the standard information attribute in the mft record. At this
       * stage we haven't setup the attribute list stuff yet, so this could
       * in fact fail if the standard information is in an extent record, but
       * I don't think this actually ever happens.
       */
      err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0, 0, 0, NULL, 0,
                  ctx);
      if (unlikely(err)) {
            if (err == -ENOENT) {
                  /*
                   * TODO: We should be performing a hot fix here (if the
                   * recover mount option is set) by creating a new
                   * attribute.
                   */
                  ntfs_error(vi->i_sb, "$STANDARD_INFORMATION attribute "
                              "is missing.");
            }
            goto unm_err_out;
      }
      a = ctx->attr;
      /* Get the standard information attribute value. */
      si = (STANDARD_INFORMATION*)((u8*)a +
                  le16_to_cpu(a->data.resident.value_offset));

      /* Transfer information from the standard information into vi. */
      /*
       * Note: The i_?times do not quite map perfectly onto the NTFS times,
       * but they are close enough, and in the end it doesn't really matter
       * that much...
       */
      /*
       * mtime is the last change of the data within the file. Not changed
       * when only metadata is changed, e.g. a rename doesn't affect mtime.
       */
      vi->i_mtime = ntfs2utc(si->last_data_change_time);
      /*
       * ctime is the last change of the metadata of the file. This obviously
       * always changes, when mtime is changed. ctime can be changed on its
       * own, mtime is then not changed, e.g. when a file is renamed.
       */
      vi->i_ctime = ntfs2utc(si->last_mft_change_time);
      /*
       * Last access to the data within the file. Not changed during a rename
       * for example but changed whenever the file is written to.
       */
      vi->i_atime = ntfs2utc(si->last_access_time);

      /* Find the attribute list attribute if present. */
      ntfs_attr_reinit_search_ctx(ctx);
      err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
      if (err) {
            if (unlikely(err != -ENOENT)) {
                  ntfs_error(vi->i_sb, "Failed to lookup attribute list "
                              "attribute.");
                  goto unm_err_out;
            }
      } else /* if (!err) */ {
            if (vi->i_ino == FILE_MFT)
                  goto skip_attr_list_load;
            ntfs_debug("Attribute list found in inode 0x%lx.", vi->i_ino);
            NInoSetAttrList(ni);
            a = ctx->attr;
            if (a->flags & ATTR_COMPRESSION_MASK) {
                  ntfs_error(vi->i_sb, "Attribute list attribute is "
                              "compressed.");
                  goto unm_err_out;
            }
            if (a->flags & ATTR_IS_ENCRYPTED ||
                        a->flags & ATTR_IS_SPARSE) {
                  if (a->non_resident) {
                        ntfs_error(vi->i_sb, "Non-resident attribute "
                                    "list attribute is encrypted/"
                                    "sparse.");
                        goto unm_err_out;
                  }
                  ntfs_warning(vi->i_sb, "Resident attribute list "
                              "attribute in inode 0x%lx is marked "
                              "encrypted/sparse which is not true.  "
                              "However, Windows allows this and "
                              "chkdsk does not detect or correct it "
                              "so we will just ignore the invalid "
                              "flags and pretend they are not set.",
                              vi->i_ino);
            }
            /* Now allocate memory for the attribute list. */
            ni->attr_list_size = (u32)ntfs_attr_size(a);
            ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
            if (!ni->attr_list) {
                  ntfs_error(vi->i_sb, "Not enough memory to allocate "
                              "buffer for attribute list.");
                  err = -ENOMEM;
                  goto unm_err_out;
            }
            if (a->non_resident) {
                  NInoSetAttrListNonResident(ni);
                  if (a->data.non_resident.lowest_vcn) {
                        ntfs_error(vi->i_sb, "Attribute list has non "
                                    "zero lowest_vcn.");
                        goto unm_err_out;
                  }
                  /*
                   * Setup the runlist. No need for locking as we have
                   * exclusive access to the inode at this time.
                   */
                  ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
                              a, NULL);
                  if (IS_ERR(ni->attr_list_rl.rl)) {
                        err = PTR_ERR(ni->attr_list_rl.rl);
                        ni->attr_list_rl.rl = NULL;
                        ntfs_error(vi->i_sb, "Mapping pairs "
                                    "decompression failed.");
                        goto unm_err_out;
                  }
                  /* Now load the attribute list. */
                  if ((err = load_attribute_list(vol, &ni->attr_list_rl,
                              ni->attr_list, ni->attr_list_size,
                              sle64_to_cpu(a->data.non_resident.
                              initialized_size)))) {
                        ntfs_error(vi->i_sb, "Failed to load "
                                    "attribute list attribute.");
                        goto unm_err_out;
                  }
            } else /* if (!a->non_resident) */ {
                  if ((u8*)a + le16_to_cpu(a->data.resident.value_offset)
                              + le32_to_cpu(
                              a->data.resident.value_length) >
                              (u8*)ctx->mrec + vol->mft_record_size) {
                        ntfs_error(vi->i_sb, "Corrupt attribute list "
                                    "in inode.");
                        goto unm_err_out;
                  }
                  /* Now copy the attribute list. */
                  memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
                              a->data.resident.value_offset),
                              le32_to_cpu(
                              a->data.resident.value_length));
            }
      }
skip_attr_list_load:
      /*
       * If an attribute list is present we now have the attribute list value
       * in ntfs_ino->attr_list and it is ntfs_ino->attr_list_size bytes.
       */
      if (S_ISDIR(vi->i_mode)) {
            loff_t bvi_size;
            struct inode *bvi;
            ntfs_inode *bni;
            INDEX_ROOT *ir;
            u8 *ir_end, *index_end;

            /* It is a directory, find index root attribute. */
            ntfs_attr_reinit_search_ctx(ctx);
            err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE,
                        0, NULL, 0, ctx);
            if (unlikely(err)) {
                  if (err == -ENOENT) {
                        // FIXME: File is corrupt! Hot-fix with empty
                        // index root attribute if recovery option is
                        // set.
                        ntfs_error(vi->i_sb, "$INDEX_ROOT attribute "
                                    "is missing.");
                  }
                  goto unm_err_out;
            }
            a = ctx->attr;
            /* Set up the state. */
            if (unlikely(a->non_resident)) {
                  ntfs_error(vol->sb, "$INDEX_ROOT attribute is not "
                              "resident.");
                  goto unm_err_out;
            }
            /* Ensure the attribute name is placed before the value. */
            if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
                        le16_to_cpu(a->data.resident.value_offset)))) {
                  ntfs_error(vol->sb, "$INDEX_ROOT attribute name is "
                              "placed after the attribute value.");
                  goto unm_err_out;
            }
            /*
             * Compressed/encrypted index root just means that the newly
             * created files in that directory should be created compressed/
             * encrypted. However index root cannot be both compressed and
             * encrypted.
             */
            if (a->flags & ATTR_COMPRESSION_MASK)
                  NInoSetCompressed(ni);
            if (a->flags & ATTR_IS_ENCRYPTED) {
                  if (a->flags & ATTR_COMPRESSION_MASK) {
                        ntfs_error(vi->i_sb, "Found encrypted and "
                                    "compressed attribute.");
                        goto unm_err_out;
                  }
                  NInoSetEncrypted(ni);
            }
            if (a->flags & ATTR_IS_SPARSE)
                  NInoSetSparse(ni);
            ir = (INDEX_ROOT*)((u8*)a +
                        le16_to_cpu(a->data.resident.value_offset));
            ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
            if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
                  ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
                              "corrupt.");
                  goto unm_err_out;
            }
            index_end = (u8*)&ir->index +
                        le32_to_cpu(ir->index.index_length);
            if (index_end > ir_end) {
                  ntfs_error(vi->i_sb, "Directory index is corrupt.");
                  goto unm_err_out;
            }
            if (ir->type != AT_FILE_NAME) {
                  ntfs_error(vi->i_sb, "Indexed attribute is not "
                              "$FILE_NAME.");
                  goto unm_err_out;
            }
            if (ir->collation_rule != COLLATION_FILE_NAME) {
                  ntfs_error(vi->i_sb, "Index collation rule is not "
                              "COLLATION_FILE_NAME.");
                  goto unm_err_out;
            }
            ni->itype.index.collation_rule = ir->collation_rule;
            ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
            if (ni->itype.index.block_size &
                        (ni->itype.index.block_size - 1)) {
                  ntfs_error(vi->i_sb, "Index block size (%u) is not a "
                              "power of two.",
                              ni->itype.index.block_size);
                  goto unm_err_out;
            }
            if (ni->itype.index.block_size > PAGE_CACHE_SIZE) {
                  ntfs_error(vi->i_sb, "Index block size (%u) > "
                              "PAGE_CACHE_SIZE (%ld) is not "
                              "supported.  Sorry.",
                              ni->itype.index.block_size,
                              PAGE_CACHE_SIZE);
                  err = -EOPNOTSUPP;
                  goto unm_err_out;
            }
            if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
                  ntfs_error(vi->i_sb, "Index block size (%u) < "
                              "NTFS_BLOCK_SIZE (%i) is not "
                              "supported.  Sorry.",
                              ni->itype.index.block_size,
                              NTFS_BLOCK_SIZE);
                  err = -EOPNOTSUPP;
                  goto unm_err_out;
            }
            ni->itype.index.block_size_bits =
                        ffs(ni->itype.index.block_size) - 1;
            /* Determine the size of a vcn in the directory index. */
            if (vol->cluster_size <= ni->itype.index.block_size) {
                  ni->itype.index.vcn_size = vol->cluster_size;
                  ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
            } else {
                  ni->itype.index.vcn_size = vol->sector_size;
                  ni->itype.index.vcn_size_bits = vol->sector_size_bits;
            }

            /* Setup the index allocation attribute, even if not present. */
            NInoSetMstProtected(ni);
            ni->type = AT_INDEX_ALLOCATION;
            ni->name = I30;
            ni->name_len = 4;

            if (!(ir->index.flags & LARGE_INDEX)) {
                  /* No index allocation. */
                  vi->i_size = ni->initialized_size =
                              ni->allocated_size = 0;
                  /* We are done with the mft record, so we release it. */
                  ntfs_attr_put_search_ctx(ctx);
                  unmap_mft_record(ni);
                  m = NULL;
                  ctx = NULL;
                  goto skip_large_dir_stuff;
            } /* LARGE_INDEX: Index allocation present. Setup state. */
            NInoSetIndexAllocPresent(ni);
            /* Find index allocation attribute. */
            ntfs_attr_reinit_search_ctx(ctx);
            err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, I30, 4,
                        CASE_SENSITIVE, 0, NULL, 0, ctx);
            if (unlikely(err)) {
                  if (err == -ENOENT)
                        ntfs_error(vi->i_sb, "$INDEX_ALLOCATION "
                                    "attribute is not present but "
                                    "$INDEX_ROOT indicated it is.");
                  else
                        ntfs_error(vi->i_sb, "Failed to lookup "
                                    "$INDEX_ALLOCATION "
                                    "attribute.");
                  goto unm_err_out;
            }
            a = ctx->attr;
            if (!a->non_resident) {
                  ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
                              "is resident.");
                  goto unm_err_out;
            }
            /*
             * Ensure the attribute name is placed before the mapping pairs
             * array.
             */
            if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
                        le16_to_cpu(
                        a->data.non_resident.mapping_pairs_offset)))) {
                  ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name "
                              "is placed after the mapping pairs "
                              "array.");
                  goto unm_err_out;
            }
            if (a->flags & ATTR_IS_ENCRYPTED) {
                  ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
                              "is encrypted.");
                  goto unm_err_out;
            }
            if (a->flags & ATTR_IS_SPARSE) {
                  ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
                              "is sparse.");
                  goto unm_err_out;
            }
            if (a->flags & ATTR_COMPRESSION_MASK) {
                  ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute "
                              "is compressed.");
                  goto unm_err_out;
            }
            if (a->data.non_resident.lowest_vcn) {
                  ntfs_error(vi->i_sb, "First extent of "
                              "$INDEX_ALLOCATION attribute has non "
                              "zero lowest_vcn.");
                  goto unm_err_out;
            }
            vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
            ni->initialized_size = sle64_to_cpu(
                        a->data.non_resident.initialized_size);
            ni->allocated_size = sle64_to_cpu(
                        a->data.non_resident.allocated_size);
            /*
             * We are done with the mft record, so we release it. Otherwise
             * we would deadlock in ntfs_attr_iget().
             */
            ntfs_attr_put_search_ctx(ctx);
            unmap_mft_record(ni);
            m = NULL;
            ctx = NULL;
            /* Get the index bitmap attribute inode. */
            bvi = ntfs_attr_iget(vi, AT_BITMAP, I30, 4);
            if (IS_ERR(bvi)) {
                  ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
                  err = PTR_ERR(bvi);
                  goto unm_err_out;
            }
            ni->itype.index.bmp_ino = bvi;
            bni = NTFS_I(bvi);
            if (NInoCompressed(bni) || NInoEncrypted(bni) ||
                        NInoSparse(bni)) {
                  ntfs_error(vi->i_sb, "$BITMAP attribute is compressed "
                              "and/or encrypted and/or sparse.");
                  goto unm_err_out;
            }
            /* Consistency check bitmap size vs. index allocation size. */
            bvi_size = i_size_read(bvi);
            if ((bvi_size << 3) < (vi->i_size >>
                        ni->itype.index.block_size_bits)) {
                  ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) "
                              "for index allocation (0x%llx).",
                              bvi_size << 3, vi->i_size);
                  goto unm_err_out;
            }
skip_large_dir_stuff:
            /* Setup the operations for this inode. */
            vi->i_op = &ntfs_dir_inode_ops;
            vi->i_fop = &ntfs_dir_ops;
      } else {
            /* It is a file. */
            ntfs_attr_reinit_search_ctx(ctx);

            /* Setup the data attribute, even if not present. */
            ni->type = AT_DATA;
            ni->name = NULL;
            ni->name_len = 0;

            /* Find first extent of the unnamed data attribute. */
            err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, 0, NULL, 0, ctx);
            if (unlikely(err)) {
                  vi->i_size = ni->initialized_size =
                              ni->allocated_size = 0;
                  if (err != -ENOENT) {
                        ntfs_error(vi->i_sb, "Failed to lookup $DATA "
                                    "attribute.");
                        goto unm_err_out;
                  }
                  /*
                   * FILE_Secure does not have an unnamed $DATA
                   * attribute, so we special case it here.
                   */
                  if (vi->i_ino == FILE_Secure)
                        goto no_data_attr_special_case;
                  /*
                   * Most if not all the system files in the $Extend
                   * system directory do not have unnamed data
                   * attributes so we need to check if the parent
                   * directory of the file is FILE_Extend and if it is
                   * ignore this error. To do this we need to get the
                   * name of this inode from the mft record as the name
                   * contains the back reference to the parent directory.
                   */
                  if (ntfs_is_extended_system_file(ctx) > 0)
                        goto no_data_attr_special_case;
                  // FIXME: File is corrupt! Hot-fix with empty data
                  // attribute if recovery option is set.
                  ntfs_error(vi->i_sb, "$DATA attribute is missing.");
                  goto unm_err_out;
            }
            a = ctx->attr;
            /* Setup the state. */
            if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
                  if (a->flags & ATTR_COMPRESSION_MASK) {
                        NInoSetCompressed(ni);
                        if (vol->cluster_size > 4096) {
                              ntfs_error(vi->i_sb, "Found "
                                          "compressed data but "
                                          "compression is "
                                          "disabled due to "
                                          "cluster size (%i) > "
                                          "4kiB.",
                                          vol->cluster_size);
                              goto unm_err_out;
                        }
                        if ((a->flags & ATTR_COMPRESSION_MASK)
                                    != ATTR_IS_COMPRESSED) {
                              ntfs_error(vi->i_sb, "Found unknown "
                                          "compression method "
                                          "or corrupt file.");
                              goto unm_err_out;
                        }
                  }
                  if (a->flags & ATTR_IS_SPARSE)
                        NInoSetSparse(ni);
            }
            if (a->flags & ATTR_IS_ENCRYPTED) {
                  if (NInoCompressed(ni)) {
                        ntfs_error(vi->i_sb, "Found encrypted and "
                                    "compressed data.");
                        goto unm_err_out;
                  }
                  NInoSetEncrypted(ni);
            }
            if (a->non_resident) {
                  NInoSetNonResident(ni);
                  if (NInoCompressed(ni) || NInoSparse(ni)) {
                        if (NInoCompressed(ni) && a->data.non_resident.
                                    compression_unit != 4) {
                              ntfs_error(vi->i_sb, "Found "
                                          "non-standard "
                                          "compression unit (%u "
                                          "instead of 4).  "
                                          "Cannot handle this.",
                                          a->data.non_resident.
                                          compression_unit);
                              err = -EOPNOTSUPP;
                              goto unm_err_out;
                        }
                        if (a->data.non_resident.compression_unit) {
                              ni->itype.compressed.block_size = 1U <<
                                          (a->data.non_resident.
                                          compression_unit +
                                          vol->cluster_size_bits);
                              ni->itype.compressed.block_size_bits =
                                          ffs(ni->itype.
                                          compressed.
                                          block_size) - 1;
                              ni->itype.compressed.block_clusters =
                                          1U << a->data.
                                          non_resident.
                                          compression_unit;
                        } else {
                              ni->itype.compressed.block_size = 0;
                              ni->itype.compressed.block_size_bits =
                                          0;
                              ni->itype.compressed.block_clusters =
                                          0;
                        }
                        ni->itype.compressed.size = sle64_to_cpu(
                                    a->data.non_resident.
                                    compressed_size);
                  }
                  if (a->data.non_resident.lowest_vcn) {
                        ntfs_error(vi->i_sb, "First extent of $DATA "
                                    "attribute has non zero "
                                    "lowest_vcn.");
                        goto unm_err_out;
                  }
                  vi->i_size = sle64_to_cpu(
                              a->data.non_resident.data_size);
                  ni->initialized_size = sle64_to_cpu(
                              a->data.non_resident.initialized_size);
                  ni->allocated_size = sle64_to_cpu(
                              a->data.non_resident.allocated_size);
            } else { /* Resident attribute. */
                  vi->i_size = ni->initialized_size = le32_to_cpu(
                              a->data.resident.value_length);
                  ni->allocated_size = le32_to_cpu(a->length) -
                              le16_to_cpu(
                              a->data.resident.value_offset);
                  if (vi->i_size > ni->allocated_size) {
                        ntfs_error(vi->i_sb, "Resident data attribute "
                                    "is corrupt (size exceeds "
                                    "allocation).");
                        goto unm_err_out;
                  }
            }
no_data_attr_special_case:
            /* We are done with the mft record, so we release it. */
            ntfs_attr_put_search_ctx(ctx);
            unmap_mft_record(ni);
            m = NULL;
            ctx = NULL;
            /* Setup the operations for this inode. */
            vi->i_op = &ntfs_file_inode_ops;
            vi->i_fop = &ntfs_file_ops;
      }
      if (NInoMstProtected(ni))
            vi->i_mapping->a_ops = &ntfs_mst_aops;
      else
            vi->i_mapping->a_ops = &ntfs_aops;
      /*
       * The number of 512-byte blocks used on disk (for stat). This is in so
       * far inaccurate as it doesn't account for any named streams or other
       * special non-resident attributes, but that is how Windows works, too,
       * so we are at least consistent with Windows, if not entirely
       * consistent with the Linux Way. Doing it the Linux Way would cause a
       * significant slowdown as it would involve iterating over all
       * attributes in the mft record and adding the allocated/compressed
       * sizes of all non-resident attributes present to give us the Linux
       * correct size that should go into i_blocks (after division by 512).
       */
      if (S_ISREG(vi->i_mode) && (NInoCompressed(ni) || NInoSparse(ni)))
            vi->i_blocks = ni->itype.compressed.size >> 9;
      else
            vi->i_blocks = ni->allocated_size >> 9;
      ntfs_debug("Done.");
      return 0;

unm_err_out:
      if (!err)
            err = -EIO;
      if (ctx)
            ntfs_attr_put_search_ctx(ctx);
      if (m)
            unmap_mft_record(ni);
err_out:
      ntfs_error(vol->sb, "Failed with error code %i.  Marking corrupt "
                  "inode 0x%lx as bad.  Run chkdsk.", err, vi->i_ino);
      make_bad_inode(vi);
      if (err != -EOPNOTSUPP && err != -ENOMEM)
            NVolSetErrors(vol);
      return err;
}

/**
 * ntfs_read_locked_attr_inode - read an attribute inode from its base inode
 * @base_vi:      base inode
 * @vi:           attribute inode to read
 *
 * ntfs_read_locked_attr_inode() is called from ntfs_attr_iget() to read the
 * attribute inode described by @vi into memory from the base mft record
 * described by @base_ni.
 *
 * ntfs_read_locked_attr_inode() maps, pins and locks the base inode for
 * reading and looks up the attribute described by @vi before setting up the
 * necessary fields in @vi as well as initializing the ntfs inode.
 *
 * Q: What locks are held when the function is called?
 * A: i_state has I_LOCK set, hence the inode is locked, also
 *    i_count is set to 1, so it is not going to go away
 *
 * Return 0 on success and -errno on error.  In the error case, the inode will
 * have had make_bad_inode() executed on it.
 *
 * Note this cannot be called for AT_INDEX_ALLOCATION.
 */
static int ntfs_read_locked_attr_inode(struct inode *base_vi, struct inode *vi)
{
      ntfs_volume *vol = NTFS_SB(vi->i_sb);
      ntfs_inode *ni, *base_ni;
      MFT_RECORD *m;
      ATTR_RECORD *a;
      ntfs_attr_search_ctx *ctx;
      int err = 0;

      ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);

      ntfs_init_big_inode(vi);

      ni    = NTFS_I(vi);
      base_ni = NTFS_I(base_vi);

      /* Just mirror the values from the base inode. */
      vi->i_blksize     = base_vi->i_blksize;
      vi->i_version     = base_vi->i_version;
      vi->i_uid   = base_vi->i_uid;
      vi->i_gid   = base_vi->i_gid;
      vi->i_nlink = base_vi->i_nlink;
      vi->i_mtime = base_vi->i_mtime;
      vi->i_ctime = base_vi->i_ctime;
      vi->i_atime = base_vi->i_atime;
      vi->i_generation = ni->seq_no = base_ni->seq_no;

      /* Set inode type to zero but preserve permissions. */
      vi->i_mode  = base_vi->i_mode & ~S_IFMT;

      m = map_mft_record(base_ni);
      if (IS_ERR(m)) {
            err = PTR_ERR(m);
            goto err_out;
      }
      ctx = ntfs_attr_get_search_ctx(base_ni, m);
      if (!ctx) {
            err = -ENOMEM;
            goto unm_err_out;
      }
      /* Find the attribute. */
      err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                  CASE_SENSITIVE, 0, NULL, 0, ctx);
      if (unlikely(err))
            goto unm_err_out;
      a = ctx->attr;
      if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_SPARSE)) {
            if (a->flags & ATTR_COMPRESSION_MASK) {
                  NInoSetCompressed(ni);
                  if ((ni->type != AT_DATA) || (ni->type == AT_DATA &&
                              ni->name_len)) {
                        ntfs_error(vi->i_sb, "Found compressed "
                                    "non-data or named data "
                                    "attribute.  Please report "
                                    "you saw this message to "
                                    "linux-ntfs-dev@lists."
                                    "sourceforge.net");
                        goto unm_err_out;
                  }
                  if (vol->cluster_size > 4096) {
                        ntfs_error(vi->i_sb, "Found compressed "
                                    "attribute but compression is "
                                    "disabled due to cluster size "
                                    "(%i) > 4kiB.",
                                    vol->cluster_size);
                        goto unm_err_out;
                  }
                  if ((a->flags & ATTR_COMPRESSION_MASK) !=
                              ATTR_IS_COMPRESSED) {
                        ntfs_error(vi->i_sb, "Found unknown "
                                    "compression method.");
                        goto unm_err_out;
                  }
            }
            /*
             * The compressed/sparse flag set in an index root just means
             * to compress all files.
             */
            if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
                  ntfs_error(vi->i_sb, "Found mst protected attribute "
                              "but the attribute is %s.  Please "
                              "report you saw this message to "
                              "linux-ntfs-dev@lists.sourceforge.net",
                              NInoCompressed(ni) ? "compressed" :
                              "sparse");
                  goto unm_err_out;
            }
            if (a->flags & ATTR_IS_SPARSE)
                  NInoSetSparse(ni);
      }
      if (a->flags & ATTR_IS_ENCRYPTED) {
            if (NInoCompressed(ni)) {
                  ntfs_error(vi->i_sb, "Found encrypted and compressed "
                              "data.");
                  goto unm_err_out;
            }
            /*
             * The encryption flag set in an index root just means to
             * encrypt all files.
             */
            if (NInoMstProtected(ni) && ni->type != AT_INDEX_ROOT) {
                  ntfs_error(vi->i_sb, "Found mst protected attribute "
                              "but the attribute is encrypted.  "
                              "Please report you saw this message "
                              "to linux-ntfs-dev@lists.sourceforge."
                              "net");
                  goto unm_err_out;
            }
            if (ni->type != AT_DATA) {
                  ntfs_error(vi->i_sb, "Found encrypted non-data "
                              "attribute.");
                  goto unm_err_out;
            }
            NInoSetEncrypted(ni);
      }
      if (!a->non_resident) {
            /* Ensure the attribute name is placed before the value. */
            if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
                        le16_to_cpu(a->data.resident.value_offset)))) {
                  ntfs_error(vol->sb, "Attribute name is placed after "
                              "the attribute value.");
                  goto unm_err_out;
            }
            if (NInoMstProtected(ni)) {
                  ntfs_error(vi->i_sb, "Found mst protected attribute "
                              "but the attribute is resident.  "
                              "Please report you saw this message to "
                              "linux-ntfs-dev@lists.sourceforge.net");
                  goto unm_err_out;
            }
            vi->i_size = ni->initialized_size = le32_to_cpu(
                        a->data.resident.value_length);
            ni->allocated_size = le32_to_cpu(a->length) -
                        le16_to_cpu(a->data.resident.value_offset);
            if (vi->i_size > ni->allocated_size) {
                  ntfs_error(vi->i_sb, "Resident attribute is corrupt "
                              "(size exceeds allocation).");
                  goto unm_err_out;
            }
      } else {
            NInoSetNonResident(ni);
            /*
             * Ensure the attribute name is placed before the mapping pairs
             * array.
             */
            if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
                        le16_to_cpu(
                        a->data.non_resident.mapping_pairs_offset)))) {
                  ntfs_error(vol->sb, "Attribute name is placed after "
                              "the mapping pairs array.");
                  goto unm_err_out;
            }
            if (NInoCompressed(ni) || NInoSparse(ni)) {
                  if (NInoCompressed(ni) && a->data.non_resident.
                              compression_unit != 4) {
                        ntfs_error(vi->i_sb, "Found non-standard "
                                    "compression unit (%u instead "
                                    "of 4).  Cannot handle this.",
                                    a->data.non_resident.
                                    compression_unit);
                        err = -EOPNOTSUPP;
                        goto unm_err_out;
                  }
                  if (a->data.non_resident.compression_unit) {
                        ni->itype.compressed.block_size = 1U <<
                                    (a->data.non_resident.
                                    compression_unit +
                                    vol->cluster_size_bits);
                        ni->itype.compressed.block_size_bits =
                                    ffs(ni->itype.compressed.
                                    block_size) - 1;
                        ni->itype.compressed.block_clusters = 1U <<
                                    a->data.non_resident.
                                    compression_unit;
                  } else {
                        ni->itype.compressed.block_size = 0;
                        ni->itype.compressed.block_size_bits = 0;
                        ni->itype.compressed.block_clusters = 0;
                  }
                  ni->itype.compressed.size = sle64_to_cpu(
                              a->data.non_resident.compressed_size);
            }
            if (a->data.non_resident.lowest_vcn) {
                  ntfs_error(vi->i_sb, "First extent of attribute has "
                              "non-zero lowest_vcn.");
                  goto unm_err_out;
            }
            vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
            ni->initialized_size = sle64_to_cpu(
                        a->data.non_resident.initialized_size);
            ni->allocated_size = sle64_to_cpu(
                        a->data.non_resident.allocated_size);
      }
      /* Setup the operations for this attribute inode. */
      vi->i_op = NULL;
      vi->i_fop = NULL;
      if (NInoMstProtected(ni))
            vi->i_mapping->a_ops = &ntfs_mst_aops;
      else
            vi->i_mapping->a_ops = &ntfs_aops;
      if ((NInoCompressed(ni) || NInoSparse(ni)) && ni->type != AT_INDEX_ROOT)
            vi->i_blocks = ni->itype.compressed.size >> 9;
      else
            vi->i_blocks = ni->allocated_size >> 9;
      /*
       * Make sure the base inode does not go away and attach it to the
       * attribute inode.
       */
      igrab(base_vi);
      ni->ext.base_ntfs_ino = base_ni;
      ni->nr_extents = -1;

      ntfs_attr_put_search_ctx(ctx);
      unmap_mft_record(base_ni);

      ntfs_debug("Done.");
      return 0;

unm_err_out:
      if (!err)
            err = -EIO;
      if (ctx)
            ntfs_attr_put_search_ctx(ctx);
      unmap_mft_record(base_ni);
err_out:
      ntfs_error(vol->sb, "Failed with error code %i while reading attribute "
                  "inode (mft_no 0x%lx, type 0x%x, name_len %i).  "
                  "Marking corrupt inode and base inode 0x%lx as bad.  "
                  "Run chkdsk.", err, vi->i_ino, ni->type, ni->name_len,
                  base_vi->i_ino);
      make_bad_inode(vi);
      if (err != -ENOMEM)
            NVolSetErrors(vol);
      return err;
}

/**
 * ntfs_read_locked_index_inode - read an index inode from its base inode
 * @base_vi:      base inode
 * @vi:           index inode to read
 *
 * ntfs_read_locked_index_inode() is called from ntfs_index_iget() to read the
 * index inode described by @vi into memory from the base mft record described
 * by @base_ni.
 *
 * ntfs_read_locked_index_inode() maps, pins and locks the base inode for
 * reading and looks up the attributes relating to the index described by @vi
 * before setting up the necessary fields in @vi as well as initializing the
 * ntfs inode.
 *
 * Note, index inodes are essentially attribute inodes (NInoAttr() is true)
 * with the attribute type set to AT_INDEX_ALLOCATION.  Apart from that, they
 * are setup like directory inodes since directories are a special case of
 * indices ao they need to be treated in much the same way.  Most importantly,
 * for small indices the index allocation attribute might not actually exist.
 * However, the index root attribute always exists but this does not need to
 * have an inode associated with it and this is why we define a new inode type
 * index.  Also, like for directories, we need to have an attribute inode for
 * the bitmap attribute corresponding to the index allocation attribute and we
 * can store this in the appropriate field of the inode, just like we do for
 * normal directory inodes.
 *
 * Q: What locks are held when the function is called?
 * A: i_state has I_LOCK set, hence the inode is locked, also
 *    i_count is set to 1, so it is not going to go away
 *
 * Return 0 on success and -errno on error.  In the error case, the inode will
 * have had make_bad_inode() executed on it.
 */
static int ntfs_read_locked_index_inode(struct inode *base_vi, struct inode *vi)
{
      loff_t bvi_size;
      ntfs_volume *vol = NTFS_SB(vi->i_sb);
      ntfs_inode *ni, *base_ni, *bni;
      struct inode *bvi;
      MFT_RECORD *m;
      ATTR_RECORD *a;
      ntfs_attr_search_ctx *ctx;
      INDEX_ROOT *ir;
      u8 *ir_end, *index_end;
      int err = 0;

      ntfs_debug("Entering for i_ino 0x%lx.", vi->i_ino);
      ntfs_init_big_inode(vi);
      ni    = NTFS_I(vi);
      base_ni = NTFS_I(base_vi);
      /* Just mirror the values from the base inode. */
      vi->i_blksize     = base_vi->i_blksize;
      vi->i_version     = base_vi->i_version;
      vi->i_uid   = base_vi->i_uid;
      vi->i_gid   = base_vi->i_gid;
      vi->i_nlink = base_vi->i_nlink;
      vi->i_mtime = base_vi->i_mtime;
      vi->i_ctime = base_vi->i_ctime;
      vi->i_atime = base_vi->i_atime;
      vi->i_generation = ni->seq_no = base_ni->seq_no;
      /* Set inode type to zero but preserve permissions. */
      vi->i_mode  = base_vi->i_mode & ~S_IFMT;
      /* Map the mft record for the base inode. */
      m = map_mft_record(base_ni);
      if (IS_ERR(m)) {
            err = PTR_ERR(m);
            goto err_out;
      }
      ctx = ntfs_attr_get_search_ctx(base_ni, m);
      if (!ctx) {
            err = -ENOMEM;
            goto unm_err_out;
      }
      /* Find the index root attribute. */
      err = ntfs_attr_lookup(AT_INDEX_ROOT, ni->name, ni->name_len,
                  CASE_SENSITIVE, 0, NULL, 0, ctx);
      if (unlikely(err)) {
            if (err == -ENOENT)
                  ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is "
                              "missing.");
            goto unm_err_out;
      }
      a = ctx->attr;
      /* Set up the state. */
      if (unlikely(a->non_resident)) {
            ntfs_error(vol->sb, "$INDEX_ROOT attribute is not resident.");
            goto unm_err_out;
      }
      /* Ensure the attribute name is placed before the value. */
      if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
                  le16_to_cpu(a->data.resident.value_offset)))) {
            ntfs_error(vol->sb, "$INDEX_ROOT attribute name is placed "
                        "after the attribute value.");
            goto unm_err_out;
      }
      /*
       * Compressed/encrypted/sparse index root is not allowed, except for
       * directories of course but those are not dealt with here.
       */
      if (a->flags & (ATTR_COMPRESSION_MASK | ATTR_IS_ENCRYPTED |
                  ATTR_IS_SPARSE)) {
            ntfs_error(vi->i_sb, "Found compressed/encrypted/sparse index "
                        "root attribute.");
            goto unm_err_out;
      }
      ir = (INDEX_ROOT*)((u8*)a + le16_to_cpu(a->data.resident.value_offset));
      ir_end = (u8*)ir + le32_to_cpu(a->data.resident.value_length);
      if (ir_end > (u8*)ctx->mrec + vol->mft_record_size) {
            ntfs_error(vi->i_sb, "$INDEX_ROOT attribute is corrupt.");
            goto unm_err_out;
      }
      index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
      if (index_end > ir_end) {
            ntfs_error(vi->i_sb, "Index is corrupt.");
            goto unm_err_out;
      }
      if (ir->type) {
            ntfs_error(vi->i_sb, "Index type is not 0 (type is 0x%x).",
                        le32_to_cpu(ir->type));
            goto unm_err_out;
      }
      ni->itype.index.collation_rule = ir->collation_rule;
      ntfs_debug("Index collation rule is 0x%x.",
                  le32_to_cpu(ir->collation_rule));
      ni->itype.index.block_size = le32_to_cpu(ir->index_block_size);
      if (ni->itype.index.block_size & (ni->itype.index.block_size - 1)) {
            ntfs_error(vi->i_sb, "Index block size (%u) is not a power of "
                        "two.", ni->itype.index.block_size);
            goto unm_err_out;
      }
      if (ni->itype.index.block_size > PAGE_CACHE_SIZE) {
            ntfs_error(vi->i_sb, "Index block size (%u) > PAGE_CACHE_SIZE "
                        "(%ld) is not supported.  Sorry.",
                        ni->itype.index.block_size, PAGE_CACHE_SIZE);
            err = -EOPNOTSUPP;
            goto unm_err_out;
      }
      if (ni->itype.index.block_size < NTFS_BLOCK_SIZE) {
            ntfs_error(vi->i_sb, "Index block size (%u) < NTFS_BLOCK_SIZE "
                        "(%i) is not supported.  Sorry.",
                        ni->itype.index.block_size, NTFS_BLOCK_SIZE);
            err = -EOPNOTSUPP;
            goto unm_err_out;
      }
      ni->itype.index.block_size_bits = ffs(ni->itype.index.block_size) - 1;
      /* Determine the size of a vcn in the index. */
      if (vol->cluster_size <= ni->itype.index.block_size) {
            ni->itype.index.vcn_size = vol->cluster_size;
            ni->itype.index.vcn_size_bits = vol->cluster_size_bits;
      } else {
            ni->itype.index.vcn_size = vol->sector_size;
            ni->itype.index.vcn_size_bits = vol->sector_size_bits;
      }
      /* Check for presence of index allocation attribute. */
      if (!(ir->index.flags & LARGE_INDEX)) {
            /* No index allocation. */
            vi->i_size = ni->initialized_size = ni->allocated_size = 0;
            /* We are done with the mft record, so we release it. */
            ntfs_attr_put_search_ctx(ctx);
            unmap_mft_record(base_ni);
            m = NULL;
            ctx = NULL;
            goto skip_large_index_stuff;
      } /* LARGE_INDEX:  Index allocation present.  Setup state. */
      NInoSetIndexAllocPresent(ni);
      /* Find index allocation attribute. */
      ntfs_attr_reinit_search_ctx(ctx);
      err = ntfs_attr_lookup(AT_INDEX_ALLOCATION, ni->name, ni->name_len,
                  CASE_SENSITIVE, 0, NULL, 0, ctx);
      if (unlikely(err)) {
            if (err == -ENOENT)
                  ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
                              "not present but $INDEX_ROOT "
                              "indicated it is.");
            else
                  ntfs_error(vi->i_sb, "Failed to lookup "
                              "$INDEX_ALLOCATION attribute.");
            goto unm_err_out;
      }
      a = ctx->attr;
      if (!a->non_resident) {
            ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
                        "resident.");
            goto unm_err_out;
      }
      /*
       * Ensure the attribute name is placed before the mapping pairs array.
       */
      if (unlikely(a->name_length && (le16_to_cpu(a->name_offset) >=
                  le16_to_cpu(
                  a->data.non_resident.mapping_pairs_offset)))) {
            ntfs_error(vol->sb, "$INDEX_ALLOCATION attribute name is "
                        "placed after the mapping pairs array.");
            goto unm_err_out;
      }
      if (a->flags & ATTR_IS_ENCRYPTED) {
            ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
                        "encrypted.");
            goto unm_err_out;
      }
      if (a->flags & ATTR_IS_SPARSE) {
            ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is sparse.");
            goto unm_err_out;
      }
      if (a->flags & ATTR_COMPRESSION_MASK) {
            ntfs_error(vi->i_sb, "$INDEX_ALLOCATION attribute is "
                        "compressed.");
            goto unm_err_out;
      }
      if (a->data.non_resident.lowest_vcn) {
            ntfs_error(vi->i_sb, "First extent of $INDEX_ALLOCATION "
                        "attribute has non zero lowest_vcn.");
            goto unm_err_out;
      }
      vi->i_size = sle64_to_cpu(a->data.non_resident.data_size);
      ni->initialized_size = sle64_to_cpu(
                  a->data.non_resident.initialized_size);
      ni->allocated_size = sle64_to_cpu(a->data.non_resident.allocated_size);
      /*
       * We are done with the mft record, so we release it.  Otherwise
       * we would deadlock in ntfs_attr_iget().
       */
      ntfs_attr_put_search_ctx(ctx);
      unmap_mft_record(base_ni);
      m = NULL;
      ctx = NULL;
      /* Get the index bitmap attribute inode. */
      bvi = ntfs_attr_iget(base_vi, AT_BITMAP, ni->name, ni->name_len);
      if (IS_ERR(bvi)) {
            ntfs_error(vi->i_sb, "Failed to get bitmap attribute.");
            err = PTR_ERR(bvi);
            goto unm_err_out;
      }
      bni = NTFS_I(bvi);
      if (NInoCompressed(bni) || NInoEncrypted(bni) ||
                  NInoSparse(bni)) {
            ntfs_error(vi->i_sb, "$BITMAP attribute is compressed and/or "
                        "encrypted and/or sparse.");
            goto iput_unm_err_out;
      }
      /* Consistency check bitmap size vs. index allocation size. */
      bvi_size = i_size_read(bvi);
      if ((bvi_size << 3) < (vi->i_size >> ni->itype.index.block_size_bits)) {
            ntfs_error(vi->i_sb, "Index bitmap too small (0x%llx) for "
                        "index allocation (0x%llx).", bvi_size << 3,
                        vi->i_size);
            goto iput_unm_err_out;
      }
      ni->itype.index.bmp_ino = bvi;
skip_large_index_stuff:
      /* Setup the operations for this index inode. */
      vi->i_op = NULL;
      vi->i_fop = NULL;
      vi->i_mapping->a_ops = &ntfs_mst_aops;
      vi->i_blocks = ni->allocated_size >> 9;
      /*
       * Make sure the base inode doesn't go away and attach it to the
       * index inode.
       */
      igrab(base_vi);
      ni->ext.base_ntfs_ino = base_ni;
      ni->nr_extents = -1;

      ntfs_debug("Done.");
      return 0;

iput_unm_err_out:
      iput(bvi);
unm_err_out:
      if (!err)
            err = -EIO;
      if (ctx)
            ntfs_attr_put_search_ctx(ctx);
      if (m)
            unmap_mft_record(base_ni);
err_out:
      ntfs_error(vi->i_sb, "Failed with error code %i while reading index "
                  "inode (mft_no 0x%lx, name_len %i.", err, vi->i_ino,
                  ni->name_len);
      make_bad_inode(vi);
      if (err != -EOPNOTSUPP && err != -ENOMEM)
            NVolSetErrors(vol);
      return err;
}

/*
 * The MFT inode has special locking, so teach the lock validator
 * about this by splitting off the locking rules of the MFT from
 * the locking rules of other inodes. The MFT inode can never be
 * accessed from the VFS side (or even internally), only by the
 * map_mft functions.
 */
static struct lock_class_key mft_ni_runlist_lock_key, mft_ni_mrec_lock_key;

/**
 * ntfs_read_inode_mount - special read_inode for mount time use only
 * @vi:           inode to read
 *
 * Read inode FILE_MFT at mount time, only called with super_block lock
 * held from within the read_super() code path.
 *
 * This function exists because when it is called the page cache for $MFT/$DATA
 * is not initialized and hence we cannot get at the contents of mft records
 * by calling map_mft_record*().
 *
 * Further it needs to cope with the circular references problem, i.e. cannot
 * load any attributes other than $ATTRIBUTE_LIST until $DATA is loaded, because
 * we do not know where the other extent mft records are yet and again, because
 * we cannot call map_mft_record*() yet.  Obviously this applies only when an
 * attribute list is actually present in $MFT inode.
 *
 * We solve these problems by starting with the $DATA attribute before anything
 * else and iterating using ntfs_attr_lookup($DATA) over all extents.  As each
 * extent is found, we ntfs_mapping_pairs_decompress() including the implied
 * ntfs_runlists_merge().  Each step of the iteration necessarily provides
 * sufficient information for the next step to complete.
 *
 * This should work but there are two possible pit falls (see inline comments
 * below), but only time will tell if they are real pits or just smoke...
 */
int ntfs_read_inode_mount(struct inode *vi)
{
      VCN next_vcn, last_vcn, highest_vcn;
      s64 block;
      struct super_block *sb = vi->i_sb;
      ntfs_volume *vol = NTFS_SB(sb);
      struct buffer_head *bh;
      ntfs_inode *ni;
      MFT_RECORD *m = NULL;
      ATTR_RECORD *a;
      ntfs_attr_search_ctx *ctx;
      unsigned int i, nr_blocks;
      int err;

      ntfs_debug("Entering.");

      /* Initialize the ntfs specific part of @vi. */
      ntfs_init_big_inode(vi);

      ni = NTFS_I(vi);

      /* Setup the data attribute. It is special as it is mst protected. */
      NInoSetNonResident(ni);
      NInoSetMstProtected(ni);
      NInoSetSparseDisabled(ni);
      ni->type = AT_DATA;
      ni->name = NULL;
      ni->name_len = 0;
      /*
       * This sets up our little cheat allowing us to reuse the async read io
       * completion handler for directories.
       */
      ni->itype.index.block_size = vol->mft_record_size;
      ni->itype.index.block_size_bits = vol->mft_record_size_bits;

      /* Very important! Needed to be able to call map_mft_record*(). */
      vol->mft_ino = vi;

      /* Allocate enough memory to read the first mft record. */
      if (vol->mft_record_size > 64 * 1024) {
            ntfs_error(sb, "Unsupported mft record size %i (max 64kiB).",
                        vol->mft_record_size);
            goto err_out;
      }
      i = vol->mft_record_size;
      if (i < sb->s_blocksize)
            i = sb->s_blocksize;
      m = (MFT_RECORD*)ntfs_malloc_nofs(i);
      if (!m) {
            ntfs_error(sb, "Failed to allocate buffer for $MFT record 0.");
            goto err_out;
      }

      /* Determine the first block of the $MFT/$DATA attribute. */
      block = vol->mft_lcn << vol->cluster_size_bits >>
                  sb->s_blocksize_bits;
      nr_blocks = vol->mft_record_size >> sb->s_blocksize_bits;
      if (!nr_blocks)
            nr_blocks = 1;

      /* Load $MFT/$DATA's first mft record. */
      for (i = 0; i < nr_blocks; i++) {
            bh = sb_bread(sb, block++);
            if (!bh) {
                  ntfs_error(sb, "Device read failed.");
                  goto err_out;
            }
            memcpy((char*)m + (i << sb->s_blocksize_bits), bh->b_data,
                        sb->s_blocksize);
            brelse(bh);
      }

      /* Apply the mst fixups. */
      if (post_read_mst_fixup((NTFS_RECORD*)m, vol->mft_record_size)) {
            /* FIXME: Try to use the $MFTMirr now. */
            ntfs_error(sb, "MST fixup failed. $MFT is corrupt.");
            goto err_out;
      }

      /* Need this to sanity check attribute list references to $MFT. */
      vi->i_generation = ni->seq_no = le16_to_cpu(m->sequence_number);

      /* Provides readpage() and sync_page() for map_mft_record(). */
      vi->i_mapping->a_ops = &ntfs_mst_aops;

      ctx = ntfs_attr_get_search_ctx(ni, m);
      if (!ctx) {
            err = -ENOMEM;
            goto err_out;
      }

      /* Find the attribute list attribute if present. */
      err = ntfs_attr_lookup(AT_ATTRIBUTE_LIST, NULL, 0, 0, 0, NULL, 0, ctx);
      if (err) {
            if (unlikely(err != -ENOENT)) {
                  ntfs_error(sb, "Failed to lookup attribute list "
                              "attribute. You should run chkdsk.");
                  goto put_err_out;
            }
      } else /* if (!err) */ {
            ATTR_LIST_ENTRY *al_entry, *next_al_entry;
            u8 *al_end;
            static const char *es = "  Not allowed.  $MFT is corrupt.  "
                        "You should run chkdsk.";

            ntfs_debug("Attribute list attribute found in $MFT.");
            NInoSetAttrList(ni);
            a = ctx->attr;
            if (a->flags & ATTR_COMPRESSION_MASK) {
                  ntfs_error(sb, "Attribute list attribute is "
                              "compressed.%s", es);
                  goto put_err_out;
            }
            if (a->flags & ATTR_IS_ENCRYPTED ||
                        a->flags & ATTR_IS_SPARSE) {
                  if (a->non_resident) {
                        ntfs_error(sb, "Non-resident attribute list "
                                    "attribute is encrypted/"
                                    "sparse.%s", es);
                        goto put_err_out;
                  }
                  ntfs_warning(sb, "Resident attribute list attribute "
                              "in $MFT system file is marked "
                              "encrypted/sparse which is not true.  "
                              "However, Windows allows this and "
                              "chkdsk does not detect or correct it "
                              "so we will just ignore the invalid "
                              "flags and pretend they are not set.");
            }
            /* Now allocate memory for the attribute list. */
            ni->attr_list_size = (u32)ntfs_attr_size(a);
            ni->attr_list = ntfs_malloc_nofs(ni->attr_list_size);
            if (!ni->attr_list) {
                  ntfs_error(sb, "Not enough memory to allocate buffer "
                              "for attribute list.");
                  goto put_err_out;
            }
            if (a->non_resident) {
                  NInoSetAttrListNonResident(ni);
                  if (a->data.non_resident.lowest_vcn) {
                        ntfs_error(sb, "Attribute list has non zero "
                                    "lowest_vcn. $MFT is corrupt. "
                                    "You should run chkdsk.");
                        goto put_err_out;
                  }
                  /* Setup the runlist. */
                  ni->attr_list_rl.rl = ntfs_mapping_pairs_decompress(vol,
                              a, NULL);
                  if (IS_ERR(ni->attr_list_rl.rl)) {
                        err = PTR_ERR(ni->attr_list_rl.rl);
                        ni->attr_list_rl.rl = NULL;
                        ntfs_error(sb, "Mapping pairs decompression "
                                    "failed with error code %i.",
                                    -err);
                        goto put_err_out;
                  }
                  /* Now load the attribute list. */
                  if ((err = load_attribute_list(vol, &ni->attr_list_rl,
                              ni->attr_list, ni->attr_list_size,
                              sle64_to_cpu(a->data.
                              non_resident.initialized_size)))) {
                        ntfs_error(sb, "Failed to load attribute list "
                                    "attribute with error code %i.",
                                    -err);
                        goto put_err_out;
                  }
            } else /* if (!ctx.attr->non_resident) */ {
                  if ((u8*)a + le16_to_cpu(
                              a->data.resident.value_offset) +
                              le32_to_cpu(
                              a->data.resident.value_length) >
                              (u8*)ctx->mrec + vol->mft_record_size) {
                        ntfs_error(sb, "Corrupt attribute list "
                                    "attribute.");
                        goto put_err_out;
                  }
                  /* Now copy the attribute list. */
                  memcpy(ni->attr_list, (u8*)a + le16_to_cpu(
                              a->data.resident.value_offset),
                              le32_to_cpu(
                              a->data.resident.value_length));
            }
            /* The attribute list is now setup in memory. */
            /*
             * FIXME: I don't know if this case is actually possible.
             * According to logic it is not possible but I have seen too
             * many weird things in MS software to rely on logic... Thus we
             * perform a manual search and make sure the first $MFT/$DATA
             * extent is in the base inode. If it is not we abort with an
             * error and if we ever see a report of this error we will need
             * to do some magic in order to have the necessary mft record
             * loaded and in the right place in the page cache. But
             * hopefully logic will prevail and this never happens...
             */
            al_entry = (ATTR_LIST_ENTRY*)ni->attr_list;
            al_end = (u8*)al_entry + ni->attr_list_size;
            for (;; al_entry = next_al_entry) {
                  /* Out of bounds check. */
                  if ((u8*)al_entry < ni->attr_list ||
                              (u8*)al_entry > al_end)
                        goto em_put_err_out;
                  /* Catch the end of the attribute list. */
                  if ((u8*)al_entry == al_end)
                        goto em_put_err_out;
                  if (!al_entry->length)
                        goto em_put_err_out;
                  if ((u8*)al_entry + 6 > al_end || (u8*)al_entry +
                              le16_to_cpu(al_entry->length) > al_end)
                        goto em_put_err_out;
                  next_al_entry = (ATTR_LIST_ENTRY*)((u8*)al_entry +
                              le16_to_cpu(al_entry->length));
                  if (le32_to_cpu(al_entry->type) >
                              const_le32_to_cpu(AT_DATA))
                        goto em_put_err_out;
                  if (AT_DATA != al_entry->type)
                        continue;
                  /* We want an unnamed attribute. */
                  if (al_entry->name_length)
                        goto em_put_err_out;
                  /* Want the first entry, i.e. lowest_vcn == 0. */
                  if (al_entry->lowest_vcn)
                        goto em_put_err_out;
                  /* First entry has to be in the base mft record. */
                  if (MREF_LE(al_entry->mft_reference) != vi->i_ino) {
                        /* MFT references do not match, logic fails. */
                        ntfs_error(sb, "BUG: The first $DATA extent "
                                    "of $MFT is not in the base "
                                    "mft record. Please report "
                                    "you saw this message to "
                                    "linux-ntfs-dev@lists."
                                    "sourceforge.net");
                        goto put_err_out;
                  } else {
                        /* Sequence numbers must match. */
                        if (MSEQNO_LE(al_entry->mft_reference) !=
                                    ni->seq_no)
                              goto em_put_err_out;
                        /* Got it. All is ok. We can stop now. */
                        break;
                  }
            }
      }

      ntfs_attr_reinit_search_ctx(ctx);

      /* Now load all attribute extents. */
      a = NULL;
      next_vcn = last_vcn = highest_vcn = 0;
      while (!(err = ntfs_attr_lookup(AT_DATA, NULL, 0, 0, next_vcn, NULL, 0,
                  ctx))) {
            runlist_element *nrl;

            /* Cache the current attribute. */
            a = ctx->attr;
            /* $MFT must be non-resident. */
            if (!a->non_resident) {
                  ntfs_error(sb, "$MFT must be non-resident but a "
                              "resident extent was found. $MFT is "
                              "corrupt. Run chkdsk.");
                  goto put_err_out;
            }
            /* $MFT must be uncompressed and unencrypted. */
            if (a->flags & ATTR_COMPRESSION_MASK ||
                        a->flags & ATTR_IS_ENCRYPTED ||
                        a->flags & ATTR_IS_SPARSE) {
                  ntfs_error(sb, "$MFT must be uncompressed, "
                              "non-sparse, and unencrypted but a "
                              "compressed/sparse/encrypted extent "
                              "was found. $MFT is corrupt. Run "
                              "chkdsk.");
                  goto put_err_out;
            }
            /*
             * Decompress the mapping pairs array of this extent and merge
             * the result into the existing runlist. No need for locking
             * as we have exclusive access to the inode at this time and we
             * are a mount in progress task, too.
             */
            nrl = ntfs_mapping_pairs_decompress(vol, a, ni->runlist.rl);
            if (IS_ERR(nrl)) {
                  ntfs_error(sb, "ntfs_mapping_pairs_decompress() "
                              "failed with error code %ld.  $MFT is "
                              "corrupt.", PTR_ERR(nrl));
                  goto put_err_out;
            }
            ni->runlist.rl = nrl;

            /* Are we in the first extent? */
            if (!next_vcn) {
                  if (a->data.non_resident.lowest_vcn) {
                        ntfs_error(sb, "First extent of $DATA "
                                    "attribute has non zero "
                                    "lowest_vcn. $MFT is corrupt. "
                                    "You should run chkdsk.");
                        goto put_err_out;
                  }
                  /* Get the last vcn in the $DATA attribute. */
                  last_vcn = sle64_to_cpu(
                              a->data.non_resident.allocated_size)
                              >> vol->cluster_size_bits;
                  /* Fill in the inode size. */
                  vi->i_size = sle64_to_cpu(
                              a->data.non_resident.data_size);
                  ni->initialized_size = sle64_to_cpu(
                              a->data.non_resident.initialized_size);
                  ni->allocated_size = sle64_to_cpu(
                              a->data.non_resident.allocated_size);
                  /*
                   * Verify the number of mft records does not exceed
                   * 2^32 - 1.
                   */
                  if ((vi->i_size >> vol->mft_record_size_bits) >=
                              (1ULL << 32)) {
                        ntfs_error(sb, "$MFT is too big! Aborting.");
                        goto put_err_out;
                  }
                  /*
                   * We have got the first extent of the runlist for
                   * $MFT which means it is now relatively safe to call
                   * the normal ntfs_read_inode() function.
                   * Complete reading the inode, this will actually
                   * re-read the mft record for $MFT, this time entering
                   * it into the page cache with which we complete the
                   * kick start of the volume. It should be safe to do
                   * this now as the first extent of $MFT/$DATA is
                   * already known and we would hope that we don't need
                   * further extents in order to find the other
                   * attributes belonging to $MFT. Only time will tell if
                   * this is really the case. If not we will have to play
                   * magic at this point, possibly duplicating a lot of
                   * ntfs_read_inode() at this point. We will need to
                   * ensure we do enough of its work to be able to call
                   * ntfs_read_inode() on extents of $MFT/$DATA. But lets
                   * hope this never happens...
                   */
                  ntfs_read_locked_inode(vi);
                  if (is_bad_inode(vi)) {
                        ntfs_error(sb, "ntfs_read_inode() of $MFT "
                                    "failed. BUG or corrupt $MFT. "
                                    "Run chkdsk and if no errors "
                                    "are found, please report you "
                                    "saw this message to "
                                    "linux-ntfs-dev@lists."
                                    "sourceforge.net");
                        ntfs_attr_put_search_ctx(ctx);
                        /* Revert to the safe super operations. */
                        ntfs_free(m);
                        return -1;
                  }
                  /*
                   * Re-initialize some specifics about $MFT's inode as
                   * ntfs_read_inode() will have set up the default ones.
                   */
                  /* Set uid and gid to root. */
                  vi->i_uid = vi->i_gid = 0;
                  /* Regular file. No access for anyone. */
                  vi->i_mode = S_IFREG;
                  /* No VFS initiated operations allowed for $MFT. */
                  vi->i_op = &ntfs_empty_inode_ops;
                  vi->i_fop = &ntfs_empty_file_ops;
            }

            /* Get the lowest vcn for the next extent. */
            highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
            next_vcn = highest_vcn + 1;

            /* Only one extent or error, which we catch below. */
            if (next_vcn <= 0)
                  break;

            /* Avoid endless loops due to corruption. */
            if (next_vcn < sle64_to_cpu(
                        a->data.non_resident.lowest_vcn)) {
                  ntfs_error(sb, "$MFT has corrupt attribute list "
                              "attribute. Run chkdsk.");
                  goto put_err_out;
            }
      }
      if (err != -ENOENT) {
            ntfs_error(sb, "Failed to lookup $MFT/$DATA attribute extent. "
                        "$MFT is corrupt. Run chkdsk.");
            goto put_err_out;
      }
      if (!a) {
            ntfs_error(sb, "$MFT/$DATA attribute not found. $MFT is "
                        "corrupt. Run chkdsk.");
            goto put_err_out;
      }
      if (highest_vcn && highest_vcn != last_vcn - 1) {
            ntfs_error(sb, "Failed to load the complete runlist for "
                        "$MFT/$DATA. Driver bug or corrupt $MFT. "
                        "Run chkdsk.");
            ntfs_debug("highest_vcn = 0x%llx, last_vcn - 1 = 0x%llx",
                        (unsigned long long)highest_vcn,
                        (unsigned long long)last_vcn - 1);
            goto put_err_out;
      }
      ntfs_attr_put_search_ctx(ctx);
      ntfs_debug("Done.");
      ntfs_free(m);

      /*
       * Split the locking rules of the MFT inode from the
       * locking rules of other inodes:
       */
      lockdep_set_class(&ni->runlist.lock, &mft_ni_runlist_lock_key);
      lockdep_set_class(&ni->mrec_lock, &mft_ni_mrec_lock_key);

      return 0;

em_put_err_out:
      ntfs_error(sb, "Couldn't find first extent of $DATA attribute in "
                  "attribute list. $MFT is corrupt. Run chkdsk.");
put_err_out:
      ntfs_attr_put_search_ctx(ctx);
err_out:
      ntfs_error(sb, "Failed. Marking inode as bad.");
      make_bad_inode(vi);
      ntfs_free(m);
      return -1;
}

/**
 * ntfs_put_inode - handler for when the inode reference count is decremented
 * @vi:           vfs inode
 *
 * The VFS calls ntfs_put_inode() every time the inode reference count (i_count)
 * is about to be decremented (but before the decrement itself.
 *
 * If the inode @vi is a directory with two references, one of which is being
 * dropped, we need to put the attribute inode for the directory index bitmap,
 * if it is present, otherwise the directory inode would remain pinned for
 * ever.
 */
void ntfs_put_inode(struct inode *vi)
{
      if (S_ISDIR(vi->i_mode) && atomic_read(&vi->i_count) == 2) {
            ntfs_inode *ni = NTFS_I(vi);
            if (NInoIndexAllocPresent(ni)) {
                  struct inode *bvi = NULL;
                  mutex_lock(&vi->i_mutex);
                  if (atomic_read(&vi->i_count) == 2) {
                        bvi = ni->itype.index.bmp_ino;
                        if (bvi)
                              ni->itype.index.bmp_ino = NULL;
                  }
                  mutex_unlock(&vi->i_mutex);
                  if (bvi)
                        iput(bvi);
            }
      }
}

static void __ntfs_clear_inode(ntfs_inode *ni)
{
      /* Free all alocated memory. */
      down_write(&ni->runlist.lock);
      if (ni->runlist.rl) {
            ntfs_free(ni->runlist.rl);
            ni->runlist.rl = NULL;
      }
      up_write(&ni->runlist.lock);

      if (ni->attr_list) {
            ntfs_free(ni->attr_list);
            ni->attr_list = NULL;
      }

      down_write(&ni->attr_list_rl.lock);
      if (ni->attr_list_rl.rl) {
            ntfs_free(ni->attr_list_rl.rl);
            ni->attr_list_rl.rl = NULL;
      }
      up_write(&ni->attr_list_rl.lock);

      if (ni->name_len && ni->name != I30) {
            /* Catch bugs... */
            BUG_ON(!ni->name);
            kfree(ni->name);
      }
}

void ntfs_clear_extent_inode(ntfs_inode *ni)
{
      ntfs_debug("Entering for inode 0x%lx.", ni->mft_no);

      BUG_ON(NInoAttr(ni));
      BUG_ON(ni->nr_extents != -1);

#ifdef NTFS_RW
      if (NInoDirty(ni)) {
            if (!is_bad_inode(VFS_I(ni->ext.base_ntfs_ino)))
                  ntfs_error(ni->vol->sb, "Clearing dirty extent inode!  "
                              "Losing data!  This is a BUG!!!");
            // FIXME:  Do something!!!
      }
#endif /* NTFS_RW */

      __ntfs_clear_inode(ni);

      /* Bye, bye... */
      ntfs_destroy_extent_inode(ni);
}

/**
 * ntfs_clear_big_inode - clean up the ntfs specific part of an inode
 * @vi:           vfs inode pending annihilation
 *
 * When the VFS is going to remove an inode from memory, ntfs_clear_big_inode()
 * is called, which deallocates all memory belonging to the NTFS specific part
 * of the inode and returns.
 *
 * If the MFT record is dirty, we commit it before doing anything else.
 */
void ntfs_clear_big_inode(struct inode *vi)
{
      ntfs_inode *ni = NTFS_I(vi);

      /*
       * If the inode @vi is an index inode we need to put the attribute
       * inode for the index bitmap, if it is present, otherwise the index
       * inode would disappear and the attribute inode for the index bitmap
       * would no longer be referenced from anywhere and thus it would remain
       * pinned for ever.
       */
      if (NInoAttr(ni) && (ni->type == AT_INDEX_ALLOCATION) &&
                  NInoIndexAllocPresent(ni) && ni->itype.index.bmp_ino) {
            iput(ni->itype.index.bmp_ino);
            ni->itype.index.bmp_ino = NULL;
      }
#ifdef NTFS_RW
      if (NInoDirty(ni)) {
            BOOL was_bad = (is_bad_inode(vi));

            /* Committing the inode also commits all extent inodes. */
            ntfs_commit_inode(vi);

            if (!was_bad && (is_bad_inode(vi) || NInoDirty(ni))) {
                  ntfs_error(vi->i_sb, "Failed to commit dirty inode "
                              "0x%lx.  Losing data!", vi->i_ino);
                  // FIXME:  Do something!!!
            }
      }
#endif /* NTFS_RW */

      /* No need to lock at this stage as no one else has a reference. */
      if (ni->nr_extents > 0) {
            int i;

            for (i = 0; i < ni->nr_extents; i++)
                  ntfs_clear_extent_inode(ni->ext.extent_ntfs_inos[i]);
            kfree(ni->ext.extent_ntfs_inos);
      }

      __ntfs_clear_inode(ni);

      if (NInoAttr(ni)) {
            /* Release the base inode if we are holding it. */
            if (ni->nr_extents == -1) {
                  iput(VFS_I(ni->ext.base_ntfs_ino));
                  ni->nr_extents = 0;
                  ni->ext.base_ntfs_ino = NULL;
            }
      }
      return;
}

/**
 * ntfs_show_options - show mount options in /proc/mounts
 * @sf:           seq_file in which to write our mount options
 * @mnt:    vfs mount whose mount options to display
 *
 * Called by the VFS once for each mounted ntfs volume when someone reads
 * /proc/mounts in order to display the NTFS specific mount options of each
 * mount. The mount options of the vfs mount @mnt are written to the seq file
 * @sf and success is returned.
 */
int ntfs_show_options(struct seq_file *sf, struct vfsmount *mnt)
{
      ntfs_volume *vol = NTFS_SB(mnt->mnt_sb);
      int i;

      seq_printf(sf, ",uid=%i", vol->uid);
      seq_printf(sf, ",gid=%i", vol->gid);
      if (vol->fmask == vol->dmask)
            seq_printf(sf, ",umask=0%o", vol->fmask);
      else {
            seq_printf(sf, ",fmask=0%o", vol->fmask);
            seq_printf(sf, ",dmask=0%o", vol->dmask);
      }
      seq_printf(sf, ",nls=%s", vol->nls_map->charset);
      if (NVolCaseSensitive(vol))
            seq_printf(sf, ",case_sensitive");
      if (NVolShowSystemFiles(vol))
            seq_printf(sf, ",show_sys_files");
      if (!NVolSparseEnabled(vol))
            seq_printf(sf, ",disable_sparse");
      for (i = 0; on_errors_arr[i].val; i++) {
            if (on_errors_arr[i].val & vol->on_errors)
                  seq_printf(sf, ",errors=%s", on_errors_arr[i].str);
      }
      seq_printf(sf, ",mft_zone_multiplier=%i", vol->mft_zone_multiplier);
      return 0;
}

#ifdef NTFS_RW

static const char *es = "  Leaving inconsistent metadata.  Unmount and run "
            "chkdsk.";

/**
 * ntfs_truncate - called when the i_size of an ntfs inode is changed
 * @vi:           inode for which the i_size was changed
 *
 * We only support i_size changes for normal files at present, i.e. not
 * compressed and not encrypted.  This is enforced in ntfs_setattr(), see
 * below.
 *
 * The kernel guarantees that @vi is a regular file (S_ISREG() is true) and
 * that the change is allowed.
 *
 * This implies for us that @vi is a file inode rather than a directory, index,
 * or attribute inode as well as that @vi is a base inode.
 *
 * Returns 0 on success or -errno on error.
 *
 * Called with ->i_mutex held.  In all but one case ->i_alloc_sem is held for
 * writing.  The only case in the kernel where ->i_alloc_sem is not held is
 * mm/filemap.c::generic_file_buffered_write() where vmtruncate() is called
 * with the current i_size as the offset.  The analogous place in NTFS is in
 * fs/ntfs/file.c::ntfs_file_buffered_write() where we call vmtruncate() again
 * without holding ->i_alloc_sem.
 */
int ntfs_truncate(struct inode *vi)
{
      s64 new_size, old_size, nr_freed, new_alloc_size, old_alloc_size;
      VCN highest_vcn;
      unsigned long flags;
      ntfs_inode *base_ni, *ni = NTFS_I(vi);
      ntfs_volume *vol = ni->vol;
      ntfs_attr_search_ctx *ctx;
      MFT_RECORD *m;
      ATTR_RECORD *a;
      const char *te = "  Leaving file length out of sync with i_size.";
      int err, mp_size, size_change, alloc_change;
      u32 attr_len;

      ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
      BUG_ON(NInoAttr(ni));
      BUG_ON(S_ISDIR(vi->i_mode));
      BUG_ON(NInoMstProtected(ni));
      BUG_ON(ni->nr_extents < 0);
retry_truncate:
      /*
       * Lock the runlist for writing and map the mft record to ensure it is
       * safe to mess with the attribute runlist and sizes.
       */
      down_write(&ni->runlist.lock);
      if (!NInoAttr(ni))
            base_ni = ni;
      else
            base_ni = ni->ext.base_ntfs_ino;
      m = map_mft_record(base_ni);
      if (IS_ERR(m)) {
            err = PTR_ERR(m);
            ntfs_error(vi->i_sb, "Failed to map mft record for inode 0x%lx "
                        "(error code %d).%s", vi->i_ino, err, te);
            ctx = NULL;
            m = NULL;
            goto old_bad_out;
      }
      ctx = ntfs_attr_get_search_ctx(base_ni, m);
      if (unlikely(!ctx)) {
            ntfs_error(vi->i_sb, "Failed to allocate a search context for "
                        "inode 0x%lx (not enough memory).%s",
                        vi->i_ino, te);
            err = -ENOMEM;
            goto old_bad_out;
      }
      err = ntfs_attr_lookup(ni->type, ni->name, ni->name_len,
                  CASE_SENSITIVE, 0, NULL, 0, ctx);
      if (unlikely(err)) {
            if (err == -ENOENT) {
                  ntfs_error(vi->i_sb, "Open attribute is missing from "
                              "mft record.  Inode 0x%lx is corrupt.  "
                              "Run chkdsk.%s", vi->i_ino, te);
                  err = -EIO;
            } else
                  ntfs_error(vi->i_sb, "Failed to lookup attribute in "
                              "inode 0x%lx (error code %d).%s",
                              vi->i_ino, err, te);
            goto old_bad_out;
      }
      m = ctx->mrec;
      a = ctx->attr;
      /*
       * The i_size of the vfs inode is the new size for the attribute value.
       */
      new_size = i_size_read(vi);
      /* The current size of the attribute value is the old size. */
      old_size = ntfs_attr_size(a);
      /* Calculate the new allocated size. */
      if (NInoNonResident(ni))
            new_alloc_size = (new_size + vol->cluster_size - 1) &
                        ~(s64)vol->cluster_size_mask;
      else
            new_alloc_size = (new_size + 7) & ~7;
      /* The current allocated size is the old allocated size. */
      read_lock_irqsave(&ni->size_lock, flags);
      old_alloc_size = ni->allocated_size;
      read_unlock_irqrestore(&ni->size_lock, flags);
      /*
       * The change in the file size.  This will be 0 if no change, >0 if the
       * size is growing, and <0 if the size is shrinking.
       */
      size_change = -1;
      if (new_size - old_size >= 0) {
            size_change = 1;
            if (new_size == old_size)
                  size_change = 0;
      }
      /* As above for the allocated size. */
      alloc_change = -1;
      if (new_alloc_size - old_alloc_size >= 0) {
            alloc_change = 1;
            if (new_alloc_size == old_alloc_size)
                  alloc_change = 0;
      }
      /*
       * If neither the size nor the allocation are being changed there is
       * nothing to do.
       */
      if (!size_change && !alloc_change)
            goto unm_done;
      /* If the size is changing, check if new size is allowed in $AttrDef. */
      if (size_change) {
            err = ntfs_attr_size_bounds_check(vol, ni->type, new_size);
            if (unlikely(err)) {
                  if (err == -ERANGE) {
                        ntfs_error(vol->sb, "Truncate would cause the "
                                    "inode 0x%lx to %simum size "
                                    "for its attribute type "
                                    "(0x%x).  Aborting truncate.",
                                    vi->i_ino,
                                    new_size > old_size ? "exceed "
                                    "the max" : "go under the min",
                                    le32_to_cpu(ni->type));
                        err = -EFBIG;
                  } else {
                        ntfs_error(vol->sb, "Inode 0x%lx has unknown "
                                    "attribute type 0x%x.  "
                                    "Aborting truncate.",
                                    vi->i_ino,
                                    le32_to_cpu(ni->type));
                        err = -EIO;
                  }
                  /* Reset the vfs inode size to the old size. */
                  i_size_write(vi, old_size);
                  goto err_out;
            }
      }
      if (NInoCompressed(ni) || NInoEncrypted(ni)) {
            ntfs_warning(vi->i_sb, "Changes in inode size are not "
                        "supported yet for %s files, ignoring.",
                        NInoCompressed(ni) ? "compressed" :
                        "encrypted");
            err = -EOPNOTSUPP;
            goto bad_out;
      }
      if (a->non_resident)
            goto do_non_resident_truncate;
      BUG_ON(NInoNonResident(ni));
      /* Resize the attribute record to best fit the new attribute size. */
      if (new_size < vol->mft_record_size &&
                  !ntfs_resident_attr_value_resize(m, a, new_size)) {
            unsigned long flags;

            /* The resize succeeded! */
            flush_dcache_mft_record_page(ctx->ntfs_ino);
            mark_mft_record_dirty(ctx->ntfs_ino);
            write_lock_irqsave(&ni->size_lock, flags);
            /* Update the sizes in the ntfs inode and all is done. */
            ni->allocated_size = le32_to_cpu(a->length) -
                        le16_to_cpu(a->data.resident.value_offset);
            /*
             * Note ntfs_resident_attr_value_resize() has already done any
             * necessary data clearing in the attribute record.  When the
             * file is being shrunk vmtruncate() will already have cleared
             * the top part of the last partial page, i.e. since this is
             * the resident case this is the page with index 0.  However,
             * when the file is being expanded, the page cache page data
             * between the old data_size, i.e. old_size, and the new_size
             * has not been zeroed.  Fortunately, we do not need to zero it
             * either since on one hand it will either already be zero due
             * to both readpage and writepage clearing partial page data
             * beyond i_size in which case there is nothing to do or in the
             * case of the file being mmap()ped at the same time, POSIX
             * specifies that the behaviour is unspecified thus we do not
             * have to do anything.  This means that in our implementation
             * in the rare case that the file is mmap()ped and a write
             * occured into the mmap()ped region just beyond the file size
             * and writepage has not yet been called to write out the page
             * (which would clear the area beyond the file size) and we now
             * extend the file size to incorporate this dirty region
             * outside the file size, a write of the page would result in
             * this data being written to disk instead of being cleared.
             * Given both POSIX and the Linux mmap(2) man page specify that
             * this corner case is undefined, we choose to leave it like
             * that as this is much simpler for us as we cannot lock the
             * relevant page now since we are holding too many ntfs locks
             * which would result in a lock reversal deadlock.
             */
            ni->initialized_size = new_size;
            write_unlock_irqrestore(&ni->size_lock, flags);
            goto unm_done;
      }
      /* If the above resize failed, this must be an attribute extension. */
      BUG_ON(size_change < 0);
      /*
       * We have to drop all the locks so we can call
       * ntfs_attr_make_non_resident().  This could be optimised by try-
       * locking the first page cache page and only if that fails dropping
       * the locks, locking the page, and redoing all the locking and
       * lookups.  While this would be a huge optimisation, it is not worth
       * it as this is definitely a slow code path as it only ever can happen
       * once for any given file.
       */
      ntfs_attr_put_search_ctx(ctx);
      unmap_mft_record(base_ni);
      up_write(&ni->runlist.lock);
      /*
       * Not enough space in the mft record, try to make the attribute
       * non-resident and if successful restart the truncation process.
       */
      err = ntfs_attr_make_non_resident(ni, old_size);
      if (likely(!err))
            goto retry_truncate;
      /*
       * Could not make non-resident.  If this is due to this not being
       * permitted for this attribute type or there not being enough space,
       * try to make other attributes non-resident.  Otherwise fail.
       */
      if (unlikely(err != -EPERM && err != -ENOSPC)) {
            ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, attribute "
                        "type 0x%x, because the conversion from "
                        "resident to non-resident attribute failed "
                        "with error code %i.", vi->i_ino,
                        (unsigned)le32_to_cpu(ni->type), err);
            if (err != -ENOMEM)
                  err = -EIO;
            goto conv_err_out;
      }
      /* TODO: Not implemented from here, abort. */
      if (err == -ENOSPC)
            ntfs_error(vol->sb, "Not enough space in the mft record/on "
                        "disk for the non-resident attribute value.  "
                        "This case is not implemented yet.");
      else /* if (err == -EPERM) */
            ntfs_error(vol->sb, "This attribute type may not be "
                        "non-resident.  This case is not implemented "
                        "yet.");
      err = -EOPNOTSUPP;
      goto conv_err_out;
#if 0
      // TODO: Attempt to make other attributes non-resident.
      if (!err)
            goto do_resident_extend;
      /*
       * Both the attribute list attribute and the standard information
       * attribute must remain in the base inode.  Thus, if this is one of
       * these attributes, we have to try to move other attributes out into
       * extent mft records instead.
       */
      if (ni->type == AT_ATTRIBUTE_LIST ||
                  ni->type == AT_STANDARD_INFORMATION) {
            // TODO: Attempt to move other attributes into extent mft
            // records.
            err = -EOPNOTSUPP;
            if (!err)
                  goto do_resident_extend;
            goto err_out;
      }
      // TODO: Attempt to move this attribute to an extent mft record, but
      // only if it is not already the only attribute in an mft record in
      // which case there would be nothing to gain.
      err = -EOPNOTSUPP;
      if (!err)
            goto do_resident_extend;
      /* There is nothing we can do to make enough space. )-: */
      goto err_out;
#endif
do_non_resident_truncate:
      BUG_ON(!NInoNonResident(ni));
      if (alloc_change < 0) {
            highest_vcn = sle64_to_cpu(a->data.non_resident.highest_vcn);
            if (highest_vcn > 0 &&
                        old_alloc_size >> vol->cluster_size_bits >
                        highest_vcn + 1) {
                  /*
                   * This attribute has multiple extents.  Not yet
                   * supported.
                   */
                  ntfs_error(vol->sb, "Cannot truncate inode 0x%lx, "
                              "attribute type 0x%x, because the "
                              "attribute is highly fragmented (it "
                              "consists of multiple extents) and "
                              "this case is not implemented yet.",
                              vi->i_ino,
                              (unsigned)le32_to_cpu(ni->type));
                  err = -EOPNOTSUPP;
                  goto bad_out;
            }
      }
      /*
       * If the size is shrinking, need to reduce the initialized_size and
       * the data_size before reducing the allocation.
       */
      if (size_change < 0) {
            /*
             * Make the valid size smaller (i_size is already up-to-date).
             */
            write_lock_irqsave(&ni->size_lock, flags);
            if (new_size < ni->initialized_size) {
                  ni->initialized_size = new_size;
                  a->data.non_resident.initialized_size =
                              cpu_to_sle64(new_size);
            }
            a->data.non_resident.data_size = cpu_to_sle64(new_size);
            write_unlock_irqrestore(&ni->size_lock, flags);
            flush_dcache_mft_record_page(ctx->ntfs_ino);
            mark_mft_record_dirty(ctx->ntfs_ino);
            /* If the allocated size is not changing, we are done. */
            if (!alloc_change)
                  goto unm_done;
            /*
             * If the size is shrinking it makes no sense for the
             * allocation to be growing.
             */
            BUG_ON(alloc_change > 0);
      } else /* if (size_change >= 0) */ {
            /*
             * The file size is growing or staying the same but the
             * allocation can be shrinking, growing or staying the same.
             */
            if (alloc_change > 0) {
                  /*
                   * We need to extend the allocation and possibly update
                   * the data size.  If we are updating the data size,
                   * since we are not touching the initialized_size we do
                   * not need to worry about the actual data on disk.
                   * And as far as the page cache is concerned, there
                   * will be no pages beyond the old data size and any
                   * partial region in the last page between the old and
                   * new data size (or the end of the page if the new
                   * data size is outside the page) does not need to be
                   * modified as explained above for the resident
                   * attribute truncate case.  To do this, we simply drop
                   * the locks we hold and leave all the work to our
                   * friendly helper ntfs_attr_extend_allocation().
                   */
                  ntfs_attr_put_search_ctx(ctx);
                  unmap_mft_record(base_ni);
                  up_write(&ni->runlist.lock);
                  err = ntfs_attr_extend_allocation(ni, new_size,
                              size_change > 0 ? new_size : -1, -1);
                  /*
                   * ntfs_attr_extend_allocation() will have done error
                   * output already.
                   */
                  goto done;
            }
            if (!alloc_change)
                  goto alloc_done;
      }
      /* alloc_change < 0 */
      /* Free the clusters. */
      nr_freed = ntfs_cluster_free(ni, new_alloc_size >>
                  vol->cluster_size_bits, -1, ctx);
      m = ctx->mrec;
      a = ctx->attr;
      if (unlikely(nr_freed < 0)) {
            ntfs_error(vol->sb, "Failed to release cluster(s) (error code "
                        "%lli).  Unmount and run chkdsk to recover "
                        "the lost cluster(s).", (long long)nr_freed);
            NVolSetErrors(vol);
            nr_freed = 0;
      }
      /* Truncate the runlist. */
      err = ntfs_rl_truncate_nolock(vol, &ni->runlist,
                  new_alloc_size >> vol->cluster_size_bits);
      /*
       * If the runlist truncation failed and/or the search context is no
       * longer valid, we cannot resize the attribute record or build the
       * mapping pairs array thus we mark the inode bad so that no access to
       * the freed clusters can happen.
       */
      if (unlikely(err || IS_ERR(m))) {
            ntfs_error(vol->sb, "Failed to %s (error code %li).%s",
                        IS_ERR(m) ?
                        "restore attribute search context" :
                        "truncate attribute runlist",
                        IS_ERR(m) ? PTR_ERR(m) : err, es);
            err = -EIO;
            goto bad_out;
      }
      /* Get the size for the shrunk mapping pairs array for the runlist. */
      mp_size = ntfs_get_size_for_mapping_pairs(vol, ni->runlist.rl, 0, -1);
      if (unlikely(mp_size <= 0)) {
            ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
                        "attribute type 0x%x, because determining the "
                        "size for the mapping pairs failed with error "
                        "code %i.%s", vi->i_ino,
                        (unsigned)le32_to_cpu(ni->type), mp_size, es);
            err = -EIO;
            goto bad_out;
      }
      /*
       * Shrink the attribute record for the new mapping pairs array.  Note,
       * this cannot fail since we are making the attribute smaller thus by
       * definition there is enough space to do so.
       */
      attr_len = le32_to_cpu(a->length);
      err = ntfs_attr_record_resize(m, a, mp_size +
                  le16_to_cpu(a->data.non_resident.mapping_pairs_offset));
      BUG_ON(err);
      /*
       * Generate the mapping pairs array directly into the attribute record.
       */
      err = ntfs_mapping_pairs_build(vol, (u8*)a +
                  le16_to_cpu(a->data.non_resident.mapping_pairs_offset),
                  mp_size, ni->runlist.rl, 0, -1, NULL);
      if (unlikely(err)) {
            ntfs_error(vol->sb, "Cannot shrink allocation of inode 0x%lx, "
                        "attribute type 0x%x, because building the "
                        "mapping pairs failed with error code %i.%s",
                        vi->i_ino, (unsigned)le32_to_cpu(ni->type),
                        err, es);
            err = -EIO;
            goto bad_out;
      }
      /* Update the allocated/compressed size as well as the highest vcn. */
      a->data.non_resident.highest_vcn = cpu_to_sle64((new_alloc_size >>
                  vol->cluster_size_bits) - 1);
      write_lock_irqsave(&ni->size_lock, flags);
      ni->allocated_size = new_alloc_size;
      a->data.non_resident.allocated_size = cpu_to_sle64(new_alloc_size);
      if (NInoSparse(ni) || NInoCompressed(ni)) {
            if (nr_freed) {
                  ni->itype.compressed.size -= nr_freed <<
                              vol->cluster_size_bits;
                  BUG_ON(ni->itype.compressed.size < 0);
                  a->data.non_resident.compressed_size = cpu_to_sle64(
                              ni->itype.compressed.size);
                  vi->i_blocks = ni->itype.compressed.size >> 9;
            }
      } else
            vi->i_blocks = new_alloc_size >> 9;
      write_unlock_irqrestore(&ni->size_lock, flags);
      /*
       * We have shrunk the allocation.  If this is a shrinking truncate we
       * have already dealt with the initialized_size and the data_size above
       * and we are done.  If the truncate is only changing the allocation
       * and not the data_size, we are also done.  If this is an extending
       * truncate, need to extend the data_size now which is ensured by the
       * fact that @size_change is positive.
       */
alloc_done:
      /*
       * If the size is growing, need to update it now.  If it is shrinking,
       * we have already updated it above (before the allocation change).
       */
      if (size_change > 0)
            a->data.non_resident.data_size = cpu_to_sle64(new_size);
      /* Ensure the modified mft record is written out. */
      flush_dcache_mft_record_page(ctx->ntfs_ino);
      mark_mft_record_dirty(ctx->ntfs_ino);
unm_done:
      ntfs_attr_put_search_ctx(ctx);
      unmap_mft_record(base_ni);
      up_write(&ni->runlist.lock);
done:
      /* Update the mtime and ctime on the base inode. */
      /* normally ->truncate shouldn't update ctime or mtime,
       * but ntfs did before so it got a copy & paste version
       * of file_update_time.  one day someone should fix this
       * for real.
       */
      if (!IS_NOCMTIME(VFS_I(base_ni)) && !IS_RDONLY(VFS_I(base_ni))) {
            struct timespec now = current_fs_time(VFS_I(base_ni)->i_sb);
            int sync_it = 0;

            if (!timespec_equal(&VFS_I(base_ni)->i_mtime, &now) ||
                !timespec_equal(&VFS_I(base_ni)->i_ctime, &now))
                  sync_it = 1;
            VFS_I(base_ni)->i_mtime = now;
            VFS_I(base_ni)->i_ctime = now;

            if (sync_it)
                  mark_inode_dirty_sync(VFS_I(base_ni));
      }

      if (likely(!err)) {
            NInoClearTruncateFailed(ni);
            ntfs_debug("Done.");
      }
      return err;
old_bad_out:
      old_size = -1;
bad_out:
      if (err != -ENOMEM && err != -EOPNOTSUPP)
            NVolSetErrors(vol);
      if (err != -EOPNOTSUPP)
            NInoSetTruncateFailed(ni);
      else if (old_size >= 0)
            i_size_write(vi, old_size);
err_out:
      if (ctx)
            ntfs_attr_put_search_ctx(ctx);
      if (m)
            unmap_mft_record(base_ni);
      up_write(&ni->runlist.lock);
out:
      ntfs_debug("Failed.  Returning error code %i.", err);
      return err;
conv_err_out:
      if (err != -ENOMEM && err != -EOPNOTSUPP)
            NVolSetErrors(vol);
      if (err != -EOPNOTSUPP)
            NInoSetTruncateFailed(ni);
      else
            i_size_write(vi, old_size);
      goto out;
}

/**
 * ntfs_truncate_vfs - wrapper for ntfs_truncate() that has no return value
 * @vi:           inode for which the i_size was changed
 *
 * Wrapper for ntfs_truncate() that has no return value.
 *
 * See ntfs_truncate() description above for details.
 */
void ntfs_truncate_vfs(struct inode *vi) {
      ntfs_truncate(vi);
}

/**
 * ntfs_setattr - called from notify_change() when an attribute is being changed
 * @dentry: dentry whose attributes to change
 * @attr:   structure describing the attributes and the changes
 *
 * We have to trap VFS attempts to truncate the file described by @dentry as
 * soon as possible, because we do not implement changes in i_size yet.  So we
 * abort all i_size changes here.
 *
 * We also abort all changes of user, group, and mode as we do not implement
 * the NTFS ACLs yet.
 *
 * Called with ->i_mutex held.  For the ATTR_SIZE (i.e. ->truncate) case, also
 * called with ->i_alloc_sem held for writing.
 *
 * Basically this is a copy of generic notify_change() and inode_setattr()
 * functionality, except we intercept and abort changes in i_size.
 */
int ntfs_setattr(struct dentry *dentry, struct iattr *attr)
{
      struct inode *vi = dentry->d_inode;
      int err;
      unsigned int ia_valid = attr->ia_valid;

      err = inode_change_ok(vi, attr);
      if (err)
            goto out;
      /* We do not support NTFS ACLs yet. */
      if (ia_valid & (ATTR_UID | ATTR_GID | ATTR_MODE)) {
            ntfs_warning(vi->i_sb, "Changes in user/group/mode are not "
                        "supported yet, ignoring.");
            err = -EOPNOTSUPP;
            goto out;
      }
      if (ia_valid & ATTR_SIZE) {
            if (attr->ia_size != i_size_read(vi)) {
                  ntfs_inode *ni = NTFS_I(vi);
                  /*
                   * FIXME: For now we do not support resizing of
                   * compressed or encrypted files yet.
                   */
                  if (NInoCompressed(ni) || NInoEncrypted(ni)) {
                        ntfs_warning(vi->i_sb, "Changes in inode size "
                                    "are not supported yet for "
                                    "%s files, ignoring.",
                                    NInoCompressed(ni) ?
                                    "compressed" : "encrypted");
                        err = -EOPNOTSUPP;
                  } else
                        err = vmtruncate(vi, attr->ia_size);
                  if (err || ia_valid == ATTR_SIZE)
                        goto out;
            } else {
                  /*
                   * We skipped the truncate but must still update
                   * timestamps.
                   */
                  ia_valid |= ATTR_MTIME | ATTR_CTIME;
            }
      }
      if (ia_valid & ATTR_ATIME)
            vi->i_atime = timespec_trunc(attr->ia_atime,
                        vi->i_sb->s_time_gran);
      if (ia_valid & ATTR_MTIME)
            vi->i_mtime = timespec_trunc(attr->ia_mtime,
                        vi->i_sb->s_time_gran);
      if (ia_valid & ATTR_CTIME)
            vi->i_ctime = timespec_trunc(attr->ia_ctime,
                        vi->i_sb->s_time_gran);
      mark_inode_dirty(vi);
out:
      return err;
}

/**
 * ntfs_write_inode - write out a dirty inode
 * @vi:           inode to write out
 * @sync:   if true, write out synchronously
 *
 * Write out a dirty inode to disk including any extent inodes if present.
 *
 * If @sync is true, commit the inode to disk and wait for io completion.  This
 * is done using write_mft_record().
 *
 * If @sync is false, just schedule the write to happen but do not wait for i/o
 * completion.  In 2.6 kernels, scheduling usually happens just by virtue of
 * marking the page (and in this case mft record) dirty but we do not implement
 * this yet as write_mft_record() largely ignores the @sync parameter and
 * always performs synchronous writes.
 *
 * Return 0 on success and -errno on error.
 */
int ntfs_write_inode(struct inode *vi, int sync)
{
      sle64 nt;
      ntfs_inode *ni = NTFS_I(vi);
      ntfs_attr_search_ctx *ctx;
      MFT_RECORD *m;
      STANDARD_INFORMATION *si;
      int err = 0;
      BOOL modified = FALSE;

      ntfs_debug("Entering for %sinode 0x%lx.", NInoAttr(ni) ? "attr " : "",
                  vi->i_ino);
      /*
       * Dirty attribute inodes are written via their real inodes so just
       * clean them here.  Access time updates are taken care off when the
       * real inode is written.
       */
      if (NInoAttr(ni)) {
            NInoClearDirty(ni);
            ntfs_debug("Done.");
            return 0;
      }
      /* Map, pin, and lock the mft record belonging to the inode. */
      m = map_mft_record(ni);
      if (IS_ERR(m)) {
            err = PTR_ERR(m);
            goto err_out;
      }
      /* Update the access times in the standard information attribute. */
      ctx = ntfs_attr_get_search_ctx(ni, m);
      if (unlikely(!ctx)) {
            err = -ENOMEM;
            goto unm_err_out;
      }
      err = ntfs_attr_lookup(AT_STANDARD_INFORMATION, NULL, 0,
                  CASE_SENSITIVE, 0, NULL, 0, ctx);
      if (unlikely(err)) {
            ntfs_attr_put_search_ctx(ctx);
            goto unm_err_out;
      }
      si = (STANDARD_INFORMATION*)((u8*)ctx->attr +
                  le16_to_cpu(ctx->attr->data.resident.value_offset));
      /* Update the access times if they have changed. */
      nt = utc2ntfs(vi->i_mtime);
      if (si->last_data_change_time != nt) {
            ntfs_debug("Updating mtime for inode 0x%lx: old = 0x%llx, "
                        "new = 0x%llx", vi->i_ino, (long long)
                        sle64_to_cpu(si->last_data_change_time),
                        (long long)sle64_to_cpu(nt));
            si->last_data_change_time = nt;
            modified = TRUE;
      }
      nt = utc2ntfs(vi->i_ctime);
      if (si->last_mft_change_time != nt) {
            ntfs_debug("Updating ctime for inode 0x%lx: old = 0x%llx, "
                        "new = 0x%llx", vi->i_ino, (long long)
                        sle64_to_cpu(si->last_mft_change_time),
                        (long long)sle64_to_cpu(nt));
            si->last_mft_change_time = nt;
            modified = TRUE;
      }
      nt = utc2ntfs(vi->i_atime);
      if (si->last_access_time != nt) {
            ntfs_debug("Updating atime for inode 0x%lx: old = 0x%llx, "
                        "new = 0x%llx", vi->i_ino,
                        (long long)sle64_to_cpu(si->last_access_time),
                        (long long)sle64_to_cpu(nt));
            si->last_access_time = nt;
            modified = TRUE;
      }
      /*
       * If we just modified the standard information attribute we need to
       * mark the mft record it is in dirty.  We do this manually so that
       * mark_inode_dirty() is not called which would redirty the inode and
       * hence result in an infinite loop of trying to write the inode.
       * There is no need to mark the base inode nor the base mft record
       * dirty, since we are going to write this mft record below in any case
       * and the base mft record may actually not have been modified so it
       * might not need to be written out.
       * NOTE: It is not a problem when the inode for $MFT itself is being
       * written out as mark_ntfs_record_dirty() will only set I_DIRTY_PAGES
       * on the $MFT inode and hence ntfs_write_inode() will not be
       * re-invoked because of it which in turn is ok since the dirtied mft
       * record will be cleaned and written out to disk below, i.e. before
       * this function returns.
       */
      if (modified) {
            flush_dcache_mft_record_page(ctx->ntfs_ino);
            if (!NInoTestSetDirty(ctx->ntfs_ino))
                  mark_ntfs_record_dirty(ctx->ntfs_ino->page,
                              ctx->ntfs_ino->page_ofs);
      }
      ntfs_attr_put_search_ctx(ctx);
      /* Now the access times are updated, write the base mft record. */
      if (NInoDirty(ni))
            err = write_mft_record(ni, m, sync);
      /* Write all attached extent mft records. */
      mutex_lock(&ni->extent_lock);
      if (ni->nr_extents > 0) {
            ntfs_inode **extent_nis = ni->ext.extent_ntfs_inos;
            int i;

            ntfs_debug("Writing %i extent inodes.", ni->nr_extents);
            for (i = 0; i < ni->nr_extents; i++) {
                  ntfs_inode *tni = extent_nis[i];

                  if (NInoDirty(tni)) {
                        MFT_RECORD *tm = map_mft_record(tni);
                        int ret;

                        if (IS_ERR(tm)) {
                              if (!err || err == -ENOMEM)
                                    err = PTR_ERR(tm);
                              continue;
                        }
                        ret = write_mft_record(tni, tm, sync);
                        unmap_mft_record(tni);
                        if (unlikely(ret)) {
                              if (!err || err == -ENOMEM)
                                    err = ret;
                        }
                  }
            }
      }
      mutex_unlock(&ni->extent_lock);
      unmap_mft_record(ni);
      if (unlikely(err))
            goto err_out;
      ntfs_debug("Done.");
      return 0;
unm_err_out:
      unmap_mft_record(ni);
err_out:
      if (err == -ENOMEM) {
            ntfs_warning(vi->i_sb, "Not enough memory to write inode.  "
                        "Marking the inode dirty again, so the VFS "
                        "retries later.");
            mark_inode_dirty(vi);
      } else {
            ntfs_error(vi->i_sb, "Failed (error %i):  Run chkdsk.", -err);
            NVolSetErrors(ni->vol);
      }
      return err;
}

#endif /* NTFS_RW */

Generated by  Doxygen 1.6.0   Back to index