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https://github.com/AuxXxilium/linux_dsm_epyc7002.git
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956ce2083c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
1554 lines
52 KiB
C
1554 lines
52 KiB
C
/**
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* dir.c - NTFS kernel directory operations. Part of the Linux-NTFS project.
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*
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* Copyright (c) 2001-2007 Anton Altaparmakov
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* Copyright (c) 2002 Richard Russon
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*
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* This program/include file is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public License as published
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* by the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program/include file is distributed in the hope that it will be
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* useful, but WITHOUT ANY WARRANTY; without even the implied warranty
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* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program (in the main directory of the Linux-NTFS
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* distribution in the file COPYING); if not, write to the Free Software
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* Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*/
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#include <linux/buffer_head.h>
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#include <linux/slab.h>
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#include "dir.h"
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#include "aops.h"
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#include "attrib.h"
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#include "mft.h"
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#include "debug.h"
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#include "ntfs.h"
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/**
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* The little endian Unicode string $I30 as a global constant.
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*/
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ntfschar I30[5] = { cpu_to_le16('$'), cpu_to_le16('I'),
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cpu_to_le16('3'), cpu_to_le16('0'), 0 };
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/**
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* ntfs_lookup_inode_by_name - find an inode in a directory given its name
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* @dir_ni: ntfs inode of the directory in which to search for the name
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* @uname: Unicode name for which to search in the directory
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* @uname_len: length of the name @uname in Unicode characters
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* @res: return the found file name if necessary (see below)
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*
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* Look for an inode with name @uname in the directory with inode @dir_ni.
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* ntfs_lookup_inode_by_name() walks the contents of the directory looking for
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* the Unicode name. If the name is found in the directory, the corresponding
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* inode number (>= 0) is returned as a mft reference in cpu format, i.e. it
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* is a 64-bit number containing the sequence number.
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*
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* On error, a negative value is returned corresponding to the error code. In
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* particular if the inode is not found -ENOENT is returned. Note that you
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* can't just check the return value for being negative, you have to check the
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* inode number for being negative which you can extract using MREC(return
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* value).
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*
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* Note, @uname_len does not include the (optional) terminating NULL character.
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*
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* Note, we look for a case sensitive match first but we also look for a case
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* insensitive match at the same time. If we find a case insensitive match, we
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* save that for the case that we don't find an exact match, where we return
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* the case insensitive match and setup @res (which we allocate!) with the mft
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* reference, the file name type, length and with a copy of the little endian
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* Unicode file name itself. If we match a file name which is in the DOS name
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* space, we only return the mft reference and file name type in @res.
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* ntfs_lookup() then uses this to find the long file name in the inode itself.
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* This is to avoid polluting the dcache with short file names. We want them to
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* work but we don't care for how quickly one can access them. This also fixes
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* the dcache aliasing issues.
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*
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* Locking: - Caller must hold i_mutex on the directory.
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* - Each page cache page in the index allocation mapping must be
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* locked whilst being accessed otherwise we may find a corrupt
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* page due to it being under ->writepage at the moment which
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* applies the mst protection fixups before writing out and then
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* removes them again after the write is complete after which it
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* unlocks the page.
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*/
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MFT_REF ntfs_lookup_inode_by_name(ntfs_inode *dir_ni, const ntfschar *uname,
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const int uname_len, ntfs_name **res)
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{
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ntfs_volume *vol = dir_ni->vol;
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struct super_block *sb = vol->sb;
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MFT_RECORD *m;
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INDEX_ROOT *ir;
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INDEX_ENTRY *ie;
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INDEX_ALLOCATION *ia;
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u8 *index_end;
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u64 mref;
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ntfs_attr_search_ctx *ctx;
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int err, rc;
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VCN vcn, old_vcn;
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struct address_space *ia_mapping;
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struct page *page;
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u8 *kaddr;
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ntfs_name *name = NULL;
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BUG_ON(!S_ISDIR(VFS_I(dir_ni)->i_mode));
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BUG_ON(NInoAttr(dir_ni));
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/* Get hold of the mft record for the directory. */
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m = map_mft_record(dir_ni);
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if (IS_ERR(m)) {
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ntfs_error(sb, "map_mft_record() failed with error code %ld.",
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-PTR_ERR(m));
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return ERR_MREF(PTR_ERR(m));
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}
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ctx = ntfs_attr_get_search_ctx(dir_ni, m);
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if (unlikely(!ctx)) {
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err = -ENOMEM;
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goto err_out;
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}
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/* Find the index root attribute in the mft record. */
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err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL,
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0, ctx);
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if (unlikely(err)) {
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if (err == -ENOENT) {
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ntfs_error(sb, "Index root attribute missing in "
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"directory inode 0x%lx.",
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dir_ni->mft_no);
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err = -EIO;
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}
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goto err_out;
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}
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/* Get to the index root value (it's been verified in read_inode). */
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ir = (INDEX_ROOT*)((u8*)ctx->attr +
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le16_to_cpu(ctx->attr->data.resident.value_offset));
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index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
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/* The first index entry. */
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ie = (INDEX_ENTRY*)((u8*)&ir->index +
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le32_to_cpu(ir->index.entries_offset));
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/*
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* Loop until we exceed valid memory (corruption case) or until we
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* reach the last entry.
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*/
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for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
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/* Bounds checks. */
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if ((u8*)ie < (u8*)ctx->mrec || (u8*)ie +
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sizeof(INDEX_ENTRY_HEADER) > index_end ||
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(u8*)ie + le16_to_cpu(ie->key_length) >
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index_end)
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goto dir_err_out;
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/*
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* The last entry cannot contain a name. It can however contain
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* a pointer to a child node in the B+tree so we just break out.
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*/
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if (ie->flags & INDEX_ENTRY_END)
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break;
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/*
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* We perform a case sensitive comparison and if that matches
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* we are done and return the mft reference of the inode (i.e.
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* the inode number together with the sequence number for
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* consistency checking). We convert it to cpu format before
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* returning.
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*/
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if (ntfs_are_names_equal(uname, uname_len,
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(ntfschar*)&ie->key.file_name.file_name,
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ie->key.file_name.file_name_length,
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CASE_SENSITIVE, vol->upcase, vol->upcase_len)) {
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found_it:
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/*
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* We have a perfect match, so we don't need to care
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* about having matched imperfectly before, so we can
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* free name and set *res to NULL.
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* However, if the perfect match is a short file name,
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* we need to signal this through *res, so that
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* ntfs_lookup() can fix dcache aliasing issues.
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* As an optimization we just reuse an existing
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* allocation of *res.
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*/
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if (ie->key.file_name.file_name_type == FILE_NAME_DOS) {
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if (!name) {
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name = kmalloc(sizeof(ntfs_name),
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GFP_NOFS);
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if (!name) {
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err = -ENOMEM;
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goto err_out;
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}
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}
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name->mref = le64_to_cpu(
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ie->data.dir.indexed_file);
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name->type = FILE_NAME_DOS;
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name->len = 0;
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*res = name;
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} else {
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kfree(name);
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*res = NULL;
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}
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mref = le64_to_cpu(ie->data.dir.indexed_file);
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ntfs_attr_put_search_ctx(ctx);
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unmap_mft_record(dir_ni);
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return mref;
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}
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/*
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* For a case insensitive mount, we also perform a case
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* insensitive comparison (provided the file name is not in the
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* POSIX namespace). If the comparison matches, and the name is
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* in the WIN32 namespace, we cache the filename in *res so
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* that the caller, ntfs_lookup(), can work on it. If the
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* comparison matches, and the name is in the DOS namespace, we
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* only cache the mft reference and the file name type (we set
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* the name length to zero for simplicity).
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*/
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if (!NVolCaseSensitive(vol) &&
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ie->key.file_name.file_name_type &&
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ntfs_are_names_equal(uname, uname_len,
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(ntfschar*)&ie->key.file_name.file_name,
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ie->key.file_name.file_name_length,
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IGNORE_CASE, vol->upcase, vol->upcase_len)) {
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int name_size = sizeof(ntfs_name);
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u8 type = ie->key.file_name.file_name_type;
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u8 len = ie->key.file_name.file_name_length;
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/* Only one case insensitive matching name allowed. */
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if (name) {
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ntfs_error(sb, "Found already allocated name "
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"in phase 1. Please run chkdsk "
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"and if that doesn't find any "
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"errors please report you saw "
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"this message to "
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"linux-ntfs-dev@lists."
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"sourceforge.net.");
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goto dir_err_out;
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}
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if (type != FILE_NAME_DOS)
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name_size += len * sizeof(ntfschar);
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name = kmalloc(name_size, GFP_NOFS);
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if (!name) {
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err = -ENOMEM;
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goto err_out;
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}
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name->mref = le64_to_cpu(ie->data.dir.indexed_file);
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name->type = type;
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if (type != FILE_NAME_DOS) {
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name->len = len;
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memcpy(name->name, ie->key.file_name.file_name,
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len * sizeof(ntfschar));
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} else
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name->len = 0;
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*res = name;
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}
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/*
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* Not a perfect match, need to do full blown collation so we
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* know which way in the B+tree we have to go.
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*/
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rc = ntfs_collate_names(uname, uname_len,
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(ntfschar*)&ie->key.file_name.file_name,
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ie->key.file_name.file_name_length, 1,
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IGNORE_CASE, vol->upcase, vol->upcase_len);
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/*
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* If uname collates before the name of the current entry, there
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* is definitely no such name in this index but we might need to
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* descend into the B+tree so we just break out of the loop.
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*/
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if (rc == -1)
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break;
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/* The names are not equal, continue the search. */
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if (rc)
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continue;
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/*
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* Names match with case insensitive comparison, now try the
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* case sensitive comparison, which is required for proper
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* collation.
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*/
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rc = ntfs_collate_names(uname, uname_len,
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(ntfschar*)&ie->key.file_name.file_name,
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ie->key.file_name.file_name_length, 1,
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CASE_SENSITIVE, vol->upcase, vol->upcase_len);
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if (rc == -1)
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break;
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if (rc)
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continue;
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/*
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* Perfect match, this will never happen as the
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* ntfs_are_names_equal() call will have gotten a match but we
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* still treat it correctly.
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*/
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goto found_it;
|
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}
|
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/*
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* We have finished with this index without success. Check for the
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* presence of a child node and if not present return -ENOENT, unless
|
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* we have got a matching name cached in name in which case return the
|
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* mft reference associated with it.
|
|
*/
|
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if (!(ie->flags & INDEX_ENTRY_NODE)) {
|
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if (name) {
|
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ntfs_attr_put_search_ctx(ctx);
|
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unmap_mft_record(dir_ni);
|
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return name->mref;
|
|
}
|
|
ntfs_debug("Entry not found.");
|
|
err = -ENOENT;
|
|
goto err_out;
|
|
} /* Child node present, descend into it. */
|
|
/* Consistency check: Verify that an index allocation exists. */
|
|
if (!NInoIndexAllocPresent(dir_ni)) {
|
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ntfs_error(sb, "No index allocation attribute but index entry "
|
|
"requires one. Directory inode 0x%lx is "
|
|
"corrupt or driver bug.", dir_ni->mft_no);
|
|
goto err_out;
|
|
}
|
|
/* Get the starting vcn of the index_block holding the child node. */
|
|
vcn = sle64_to_cpup((sle64*)((u8*)ie + le16_to_cpu(ie->length) - 8));
|
|
ia_mapping = VFS_I(dir_ni)->i_mapping;
|
|
/*
|
|
* We are done with the index root and the mft record. Release them,
|
|
* otherwise we deadlock with ntfs_map_page().
|
|
*/
|
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ntfs_attr_put_search_ctx(ctx);
|
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unmap_mft_record(dir_ni);
|
|
m = NULL;
|
|
ctx = NULL;
|
|
descend_into_child_node:
|
|
/*
|
|
* Convert vcn to index into the index allocation attribute in units
|
|
* of PAGE_CACHE_SIZE and map the page cache page, reading it from
|
|
* disk if necessary.
|
|
*/
|
|
page = ntfs_map_page(ia_mapping, vcn <<
|
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dir_ni->itype.index.vcn_size_bits >> PAGE_CACHE_SHIFT);
|
|
if (IS_ERR(page)) {
|
|
ntfs_error(sb, "Failed to map directory index page, error %ld.",
|
|
-PTR_ERR(page));
|
|
err = PTR_ERR(page);
|
|
goto err_out;
|
|
}
|
|
lock_page(page);
|
|
kaddr = (u8*)page_address(page);
|
|
fast_descend_into_child_node:
|
|
/* Get to the index allocation block. */
|
|
ia = (INDEX_ALLOCATION*)(kaddr + ((vcn <<
|
|
dir_ni->itype.index.vcn_size_bits) & ~PAGE_CACHE_MASK));
|
|
/* Bounds checks. */
|
|
if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) {
|
|
ntfs_error(sb, "Out of bounds check failed. Corrupt directory "
|
|
"inode 0x%lx or driver bug.", dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/* Catch multi sector transfer fixup errors. */
|
|
if (unlikely(!ntfs_is_indx_record(ia->magic))) {
|
|
ntfs_error(sb, "Directory index record with vcn 0x%llx is "
|
|
"corrupt. Corrupt inode 0x%lx. Run chkdsk.",
|
|
(unsigned long long)vcn, dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
if (sle64_to_cpu(ia->index_block_vcn) != vcn) {
|
|
ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is "
|
|
"different from expected VCN (0x%llx). "
|
|
"Directory inode 0x%lx is corrupt or driver "
|
|
"bug.", (unsigned long long)
|
|
sle64_to_cpu(ia->index_block_vcn),
|
|
(unsigned long long)vcn, dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
if (le32_to_cpu(ia->index.allocated_size) + 0x18 !=
|
|
dir_ni->itype.index.block_size) {
|
|
ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode "
|
|
"0x%lx has a size (%u) differing from the "
|
|
"directory specified size (%u). Directory "
|
|
"inode is corrupt or driver bug.",
|
|
(unsigned long long)vcn, dir_ni->mft_no,
|
|
le32_to_cpu(ia->index.allocated_size) + 0x18,
|
|
dir_ni->itype.index.block_size);
|
|
goto unm_err_out;
|
|
}
|
|
index_end = (u8*)ia + dir_ni->itype.index.block_size;
|
|
if (index_end > kaddr + PAGE_CACHE_SIZE) {
|
|
ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode "
|
|
"0x%lx crosses page boundary. Impossible! "
|
|
"Cannot access! This is probably a bug in the "
|
|
"driver.", (unsigned long long)vcn,
|
|
dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length);
|
|
if (index_end > (u8*)ia + dir_ni->itype.index.block_size) {
|
|
ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of directory "
|
|
"inode 0x%lx exceeds maximum size.",
|
|
(unsigned long long)vcn, dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/* The first index entry. */
|
|
ie = (INDEX_ENTRY*)((u8*)&ia->index +
|
|
le32_to_cpu(ia->index.entries_offset));
|
|
/*
|
|
* Iterate similar to above big loop but applied to index buffer, thus
|
|
* loop until we exceed valid memory (corruption case) or until we
|
|
* reach the last entry.
|
|
*/
|
|
for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
|
|
/* Bounds check. */
|
|
if ((u8*)ie < (u8*)ia || (u8*)ie +
|
|
sizeof(INDEX_ENTRY_HEADER) > index_end ||
|
|
(u8*)ie + le16_to_cpu(ie->key_length) >
|
|
index_end) {
|
|
ntfs_error(sb, "Index entry out of bounds in "
|
|
"directory inode 0x%lx.",
|
|
dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/*
|
|
* The last entry cannot contain a name. It can however contain
|
|
* a pointer to a child node in the B+tree so we just break out.
|
|
*/
|
|
if (ie->flags & INDEX_ENTRY_END)
|
|
break;
|
|
/*
|
|
* We perform a case sensitive comparison and if that matches
|
|
* we are done and return the mft reference of the inode (i.e.
|
|
* the inode number together with the sequence number for
|
|
* consistency checking). We convert it to cpu format before
|
|
* returning.
|
|
*/
|
|
if (ntfs_are_names_equal(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length,
|
|
CASE_SENSITIVE, vol->upcase, vol->upcase_len)) {
|
|
found_it2:
|
|
/*
|
|
* We have a perfect match, so we don't need to care
|
|
* about having matched imperfectly before, so we can
|
|
* free name and set *res to NULL.
|
|
* However, if the perfect match is a short file name,
|
|
* we need to signal this through *res, so that
|
|
* ntfs_lookup() can fix dcache aliasing issues.
|
|
* As an optimization we just reuse an existing
|
|
* allocation of *res.
|
|
*/
|
|
if (ie->key.file_name.file_name_type == FILE_NAME_DOS) {
|
|
if (!name) {
|
|
name = kmalloc(sizeof(ntfs_name),
|
|
GFP_NOFS);
|
|
if (!name) {
|
|
err = -ENOMEM;
|
|
goto unm_err_out;
|
|
}
|
|
}
|
|
name->mref = le64_to_cpu(
|
|
ie->data.dir.indexed_file);
|
|
name->type = FILE_NAME_DOS;
|
|
name->len = 0;
|
|
*res = name;
|
|
} else {
|
|
kfree(name);
|
|
*res = NULL;
|
|
}
|
|
mref = le64_to_cpu(ie->data.dir.indexed_file);
|
|
unlock_page(page);
|
|
ntfs_unmap_page(page);
|
|
return mref;
|
|
}
|
|
/*
|
|
* For a case insensitive mount, we also perform a case
|
|
* insensitive comparison (provided the file name is not in the
|
|
* POSIX namespace). If the comparison matches, and the name is
|
|
* in the WIN32 namespace, we cache the filename in *res so
|
|
* that the caller, ntfs_lookup(), can work on it. If the
|
|
* comparison matches, and the name is in the DOS namespace, we
|
|
* only cache the mft reference and the file name type (we set
|
|
* the name length to zero for simplicity).
|
|
*/
|
|
if (!NVolCaseSensitive(vol) &&
|
|
ie->key.file_name.file_name_type &&
|
|
ntfs_are_names_equal(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length,
|
|
IGNORE_CASE, vol->upcase, vol->upcase_len)) {
|
|
int name_size = sizeof(ntfs_name);
|
|
u8 type = ie->key.file_name.file_name_type;
|
|
u8 len = ie->key.file_name.file_name_length;
|
|
|
|
/* Only one case insensitive matching name allowed. */
|
|
if (name) {
|
|
ntfs_error(sb, "Found already allocated name "
|
|
"in phase 2. Please run chkdsk "
|
|
"and if that doesn't find any "
|
|
"errors please report you saw "
|
|
"this message to "
|
|
"linux-ntfs-dev@lists."
|
|
"sourceforge.net.");
|
|
unlock_page(page);
|
|
ntfs_unmap_page(page);
|
|
goto dir_err_out;
|
|
}
|
|
|
|
if (type != FILE_NAME_DOS)
|
|
name_size += len * sizeof(ntfschar);
|
|
name = kmalloc(name_size, GFP_NOFS);
|
|
if (!name) {
|
|
err = -ENOMEM;
|
|
goto unm_err_out;
|
|
}
|
|
name->mref = le64_to_cpu(ie->data.dir.indexed_file);
|
|
name->type = type;
|
|
if (type != FILE_NAME_DOS) {
|
|
name->len = len;
|
|
memcpy(name->name, ie->key.file_name.file_name,
|
|
len * sizeof(ntfschar));
|
|
} else
|
|
name->len = 0;
|
|
*res = name;
|
|
}
|
|
/*
|
|
* Not a perfect match, need to do full blown collation so we
|
|
* know which way in the B+tree we have to go.
|
|
*/
|
|
rc = ntfs_collate_names(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, 1,
|
|
IGNORE_CASE, vol->upcase, vol->upcase_len);
|
|
/*
|
|
* If uname collates before the name of the current entry, there
|
|
* is definitely no such name in this index but we might need to
|
|
* descend into the B+tree so we just break out of the loop.
|
|
*/
|
|
if (rc == -1)
|
|
break;
|
|
/* The names are not equal, continue the search. */
|
|
if (rc)
|
|
continue;
|
|
/*
|
|
* Names match with case insensitive comparison, now try the
|
|
* case sensitive comparison, which is required for proper
|
|
* collation.
|
|
*/
|
|
rc = ntfs_collate_names(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, 1,
|
|
CASE_SENSITIVE, vol->upcase, vol->upcase_len);
|
|
if (rc == -1)
|
|
break;
|
|
if (rc)
|
|
continue;
|
|
/*
|
|
* Perfect match, this will never happen as the
|
|
* ntfs_are_names_equal() call will have gotten a match but we
|
|
* still treat it correctly.
|
|
*/
|
|
goto found_it2;
|
|
}
|
|
/*
|
|
* We have finished with this index buffer without success. Check for
|
|
* the presence of a child node.
|
|
*/
|
|
if (ie->flags & INDEX_ENTRY_NODE) {
|
|
if ((ia->index.flags & NODE_MASK) == LEAF_NODE) {
|
|
ntfs_error(sb, "Index entry with child node found in "
|
|
"a leaf node in directory inode 0x%lx.",
|
|
dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/* Child node present, descend into it. */
|
|
old_vcn = vcn;
|
|
vcn = sle64_to_cpup((sle64*)((u8*)ie +
|
|
le16_to_cpu(ie->length) - 8));
|
|
if (vcn >= 0) {
|
|
/* If vcn is in the same page cache page as old_vcn we
|
|
* recycle the mapped page. */
|
|
if (old_vcn << vol->cluster_size_bits >>
|
|
PAGE_CACHE_SHIFT == vcn <<
|
|
vol->cluster_size_bits >>
|
|
PAGE_CACHE_SHIFT)
|
|
goto fast_descend_into_child_node;
|
|
unlock_page(page);
|
|
ntfs_unmap_page(page);
|
|
goto descend_into_child_node;
|
|
}
|
|
ntfs_error(sb, "Negative child node vcn in directory inode "
|
|
"0x%lx.", dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/*
|
|
* No child node present, return -ENOENT, unless we have got a matching
|
|
* name cached in name in which case return the mft reference
|
|
* associated with it.
|
|
*/
|
|
if (name) {
|
|
unlock_page(page);
|
|
ntfs_unmap_page(page);
|
|
return name->mref;
|
|
}
|
|
ntfs_debug("Entry not found.");
|
|
err = -ENOENT;
|
|
unm_err_out:
|
|
unlock_page(page);
|
|
ntfs_unmap_page(page);
|
|
err_out:
|
|
if (!err)
|
|
err = -EIO;
|
|
if (ctx)
|
|
ntfs_attr_put_search_ctx(ctx);
|
|
if (m)
|
|
unmap_mft_record(dir_ni);
|
|
if (name) {
|
|
kfree(name);
|
|
*res = NULL;
|
|
}
|
|
return ERR_MREF(err);
|
|
dir_err_out:
|
|
ntfs_error(sb, "Corrupt directory. Aborting lookup.");
|
|
goto err_out;
|
|
}
|
|
|
|
#if 0
|
|
|
|
// TODO: (AIA)
|
|
// The algorithm embedded in this code will be required for the time when we
|
|
// want to support adding of entries to directories, where we require correct
|
|
// collation of file names in order not to cause corruption of the filesystem.
|
|
|
|
/**
|
|
* ntfs_lookup_inode_by_name - find an inode in a directory given its name
|
|
* @dir_ni: ntfs inode of the directory in which to search for the name
|
|
* @uname: Unicode name for which to search in the directory
|
|
* @uname_len: length of the name @uname in Unicode characters
|
|
*
|
|
* Look for an inode with name @uname in the directory with inode @dir_ni.
|
|
* ntfs_lookup_inode_by_name() walks the contents of the directory looking for
|
|
* the Unicode name. If the name is found in the directory, the corresponding
|
|
* inode number (>= 0) is returned as a mft reference in cpu format, i.e. it
|
|
* is a 64-bit number containing the sequence number.
|
|
*
|
|
* On error, a negative value is returned corresponding to the error code. In
|
|
* particular if the inode is not found -ENOENT is returned. Note that you
|
|
* can't just check the return value for being negative, you have to check the
|
|
* inode number for being negative which you can extract using MREC(return
|
|
* value).
|
|
*
|
|
* Note, @uname_len does not include the (optional) terminating NULL character.
|
|
*/
|
|
u64 ntfs_lookup_inode_by_name(ntfs_inode *dir_ni, const ntfschar *uname,
|
|
const int uname_len)
|
|
{
|
|
ntfs_volume *vol = dir_ni->vol;
|
|
struct super_block *sb = vol->sb;
|
|
MFT_RECORD *m;
|
|
INDEX_ROOT *ir;
|
|
INDEX_ENTRY *ie;
|
|
INDEX_ALLOCATION *ia;
|
|
u8 *index_end;
|
|
u64 mref;
|
|
ntfs_attr_search_ctx *ctx;
|
|
int err, rc;
|
|
IGNORE_CASE_BOOL ic;
|
|
VCN vcn, old_vcn;
|
|
struct address_space *ia_mapping;
|
|
struct page *page;
|
|
u8 *kaddr;
|
|
|
|
/* Get hold of the mft record for the directory. */
|
|
m = map_mft_record(dir_ni);
|
|
if (IS_ERR(m)) {
|
|
ntfs_error(sb, "map_mft_record() failed with error code %ld.",
|
|
-PTR_ERR(m));
|
|
return ERR_MREF(PTR_ERR(m));
|
|
}
|
|
ctx = ntfs_attr_get_search_ctx(dir_ni, m);
|
|
if (!ctx) {
|
|
err = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
/* Find the index root attribute in the mft record. */
|
|
err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL,
|
|
0, ctx);
|
|
if (unlikely(err)) {
|
|
if (err == -ENOENT) {
|
|
ntfs_error(sb, "Index root attribute missing in "
|
|
"directory inode 0x%lx.",
|
|
dir_ni->mft_no);
|
|
err = -EIO;
|
|
}
|
|
goto err_out;
|
|
}
|
|
/* Get to the index root value (it's been verified in read_inode). */
|
|
ir = (INDEX_ROOT*)((u8*)ctx->attr +
|
|
le16_to_cpu(ctx->attr->data.resident.value_offset));
|
|
index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
|
|
/* The first index entry. */
|
|
ie = (INDEX_ENTRY*)((u8*)&ir->index +
|
|
le32_to_cpu(ir->index.entries_offset));
|
|
/*
|
|
* Loop until we exceed valid memory (corruption case) or until we
|
|
* reach the last entry.
|
|
*/
|
|
for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
|
|
/* Bounds checks. */
|
|
if ((u8*)ie < (u8*)ctx->mrec || (u8*)ie +
|
|
sizeof(INDEX_ENTRY_HEADER) > index_end ||
|
|
(u8*)ie + le16_to_cpu(ie->key_length) >
|
|
index_end)
|
|
goto dir_err_out;
|
|
/*
|
|
* The last entry cannot contain a name. It can however contain
|
|
* a pointer to a child node in the B+tree so we just break out.
|
|
*/
|
|
if (ie->flags & INDEX_ENTRY_END)
|
|
break;
|
|
/*
|
|
* If the current entry has a name type of POSIX, the name is
|
|
* case sensitive and not otherwise. This has the effect of us
|
|
* not being able to access any POSIX file names which collate
|
|
* after the non-POSIX one when they only differ in case, but
|
|
* anyone doing screwy stuff like that deserves to burn in
|
|
* hell... Doing that kind of stuff on NT4 actually causes
|
|
* corruption on the partition even when using SP6a and Linux
|
|
* is not involved at all.
|
|
*/
|
|
ic = ie->key.file_name.file_name_type ? IGNORE_CASE :
|
|
CASE_SENSITIVE;
|
|
/*
|
|
* If the names match perfectly, we are done and return the
|
|
* mft reference of the inode (i.e. the inode number together
|
|
* with the sequence number for consistency checking. We
|
|
* convert it to cpu format before returning.
|
|
*/
|
|
if (ntfs_are_names_equal(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, ic,
|
|
vol->upcase, vol->upcase_len)) {
|
|
found_it:
|
|
mref = le64_to_cpu(ie->data.dir.indexed_file);
|
|
ntfs_attr_put_search_ctx(ctx);
|
|
unmap_mft_record(dir_ni);
|
|
return mref;
|
|
}
|
|
/*
|
|
* Not a perfect match, need to do full blown collation so we
|
|
* know which way in the B+tree we have to go.
|
|
*/
|
|
rc = ntfs_collate_names(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, 1,
|
|
IGNORE_CASE, vol->upcase, vol->upcase_len);
|
|
/*
|
|
* If uname collates before the name of the current entry, there
|
|
* is definitely no such name in this index but we might need to
|
|
* descend into the B+tree so we just break out of the loop.
|
|
*/
|
|
if (rc == -1)
|
|
break;
|
|
/* The names are not equal, continue the search. */
|
|
if (rc)
|
|
continue;
|
|
/*
|
|
* Names match with case insensitive comparison, now try the
|
|
* case sensitive comparison, which is required for proper
|
|
* collation.
|
|
*/
|
|
rc = ntfs_collate_names(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, 1,
|
|
CASE_SENSITIVE, vol->upcase, vol->upcase_len);
|
|
if (rc == -1)
|
|
break;
|
|
if (rc)
|
|
continue;
|
|
/*
|
|
* Perfect match, this will never happen as the
|
|
* ntfs_are_names_equal() call will have gotten a match but we
|
|
* still treat it correctly.
|
|
*/
|
|
goto found_it;
|
|
}
|
|
/*
|
|
* We have finished with this index without success. Check for the
|
|
* presence of a child node.
|
|
*/
|
|
if (!(ie->flags & INDEX_ENTRY_NODE)) {
|
|
/* No child node, return -ENOENT. */
|
|
err = -ENOENT;
|
|
goto err_out;
|
|
} /* Child node present, descend into it. */
|
|
/* Consistency check: Verify that an index allocation exists. */
|
|
if (!NInoIndexAllocPresent(dir_ni)) {
|
|
ntfs_error(sb, "No index allocation attribute but index entry "
|
|
"requires one. Directory inode 0x%lx is "
|
|
"corrupt or driver bug.", dir_ni->mft_no);
|
|
goto err_out;
|
|
}
|
|
/* Get the starting vcn of the index_block holding the child node. */
|
|
vcn = sle64_to_cpup((u8*)ie + le16_to_cpu(ie->length) - 8);
|
|
ia_mapping = VFS_I(dir_ni)->i_mapping;
|
|
/*
|
|
* We are done with the index root and the mft record. Release them,
|
|
* otherwise we deadlock with ntfs_map_page().
|
|
*/
|
|
ntfs_attr_put_search_ctx(ctx);
|
|
unmap_mft_record(dir_ni);
|
|
m = NULL;
|
|
ctx = NULL;
|
|
descend_into_child_node:
|
|
/*
|
|
* Convert vcn to index into the index allocation attribute in units
|
|
* of PAGE_CACHE_SIZE and map the page cache page, reading it from
|
|
* disk if necessary.
|
|
*/
|
|
page = ntfs_map_page(ia_mapping, vcn <<
|
|
dir_ni->itype.index.vcn_size_bits >> PAGE_CACHE_SHIFT);
|
|
if (IS_ERR(page)) {
|
|
ntfs_error(sb, "Failed to map directory index page, error %ld.",
|
|
-PTR_ERR(page));
|
|
err = PTR_ERR(page);
|
|
goto err_out;
|
|
}
|
|
lock_page(page);
|
|
kaddr = (u8*)page_address(page);
|
|
fast_descend_into_child_node:
|
|
/* Get to the index allocation block. */
|
|
ia = (INDEX_ALLOCATION*)(kaddr + ((vcn <<
|
|
dir_ni->itype.index.vcn_size_bits) & ~PAGE_CACHE_MASK));
|
|
/* Bounds checks. */
|
|
if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) {
|
|
ntfs_error(sb, "Out of bounds check failed. Corrupt directory "
|
|
"inode 0x%lx or driver bug.", dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/* Catch multi sector transfer fixup errors. */
|
|
if (unlikely(!ntfs_is_indx_record(ia->magic))) {
|
|
ntfs_error(sb, "Directory index record with vcn 0x%llx is "
|
|
"corrupt. Corrupt inode 0x%lx. Run chkdsk.",
|
|
(unsigned long long)vcn, dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
if (sle64_to_cpu(ia->index_block_vcn) != vcn) {
|
|
ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is "
|
|
"different from expected VCN (0x%llx). "
|
|
"Directory inode 0x%lx is corrupt or driver "
|
|
"bug.", (unsigned long long)
|
|
sle64_to_cpu(ia->index_block_vcn),
|
|
(unsigned long long)vcn, dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
if (le32_to_cpu(ia->index.allocated_size) + 0x18 !=
|
|
dir_ni->itype.index.block_size) {
|
|
ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode "
|
|
"0x%lx has a size (%u) differing from the "
|
|
"directory specified size (%u). Directory "
|
|
"inode is corrupt or driver bug.",
|
|
(unsigned long long)vcn, dir_ni->mft_no,
|
|
le32_to_cpu(ia->index.allocated_size) + 0x18,
|
|
dir_ni->itype.index.block_size);
|
|
goto unm_err_out;
|
|
}
|
|
index_end = (u8*)ia + dir_ni->itype.index.block_size;
|
|
if (index_end > kaddr + PAGE_CACHE_SIZE) {
|
|
ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode "
|
|
"0x%lx crosses page boundary. Impossible! "
|
|
"Cannot access! This is probably a bug in the "
|
|
"driver.", (unsigned long long)vcn,
|
|
dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length);
|
|
if (index_end > (u8*)ia + dir_ni->itype.index.block_size) {
|
|
ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of directory "
|
|
"inode 0x%lx exceeds maximum size.",
|
|
(unsigned long long)vcn, dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/* The first index entry. */
|
|
ie = (INDEX_ENTRY*)((u8*)&ia->index +
|
|
le32_to_cpu(ia->index.entries_offset));
|
|
/*
|
|
* Iterate similar to above big loop but applied to index buffer, thus
|
|
* loop until we exceed valid memory (corruption case) or until we
|
|
* reach the last entry.
|
|
*/
|
|
for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
|
|
/* Bounds check. */
|
|
if ((u8*)ie < (u8*)ia || (u8*)ie +
|
|
sizeof(INDEX_ENTRY_HEADER) > index_end ||
|
|
(u8*)ie + le16_to_cpu(ie->key_length) >
|
|
index_end) {
|
|
ntfs_error(sb, "Index entry out of bounds in "
|
|
"directory inode 0x%lx.",
|
|
dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/*
|
|
* The last entry cannot contain a name. It can however contain
|
|
* a pointer to a child node in the B+tree so we just break out.
|
|
*/
|
|
if (ie->flags & INDEX_ENTRY_END)
|
|
break;
|
|
/*
|
|
* If the current entry has a name type of POSIX, the name is
|
|
* case sensitive and not otherwise. This has the effect of us
|
|
* not being able to access any POSIX file names which collate
|
|
* after the non-POSIX one when they only differ in case, but
|
|
* anyone doing screwy stuff like that deserves to burn in
|
|
* hell... Doing that kind of stuff on NT4 actually causes
|
|
* corruption on the partition even when using SP6a and Linux
|
|
* is not involved at all.
|
|
*/
|
|
ic = ie->key.file_name.file_name_type ? IGNORE_CASE :
|
|
CASE_SENSITIVE;
|
|
/*
|
|
* If the names match perfectly, we are done and return the
|
|
* mft reference of the inode (i.e. the inode number together
|
|
* with the sequence number for consistency checking. We
|
|
* convert it to cpu format before returning.
|
|
*/
|
|
if (ntfs_are_names_equal(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, ic,
|
|
vol->upcase, vol->upcase_len)) {
|
|
found_it2:
|
|
mref = le64_to_cpu(ie->data.dir.indexed_file);
|
|
unlock_page(page);
|
|
ntfs_unmap_page(page);
|
|
return mref;
|
|
}
|
|
/*
|
|
* Not a perfect match, need to do full blown collation so we
|
|
* know which way in the B+tree we have to go.
|
|
*/
|
|
rc = ntfs_collate_names(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, 1,
|
|
IGNORE_CASE, vol->upcase, vol->upcase_len);
|
|
/*
|
|
* If uname collates before the name of the current entry, there
|
|
* is definitely no such name in this index but we might need to
|
|
* descend into the B+tree so we just break out of the loop.
|
|
*/
|
|
if (rc == -1)
|
|
break;
|
|
/* The names are not equal, continue the search. */
|
|
if (rc)
|
|
continue;
|
|
/*
|
|
* Names match with case insensitive comparison, now try the
|
|
* case sensitive comparison, which is required for proper
|
|
* collation.
|
|
*/
|
|
rc = ntfs_collate_names(uname, uname_len,
|
|
(ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, 1,
|
|
CASE_SENSITIVE, vol->upcase, vol->upcase_len);
|
|
if (rc == -1)
|
|
break;
|
|
if (rc)
|
|
continue;
|
|
/*
|
|
* Perfect match, this will never happen as the
|
|
* ntfs_are_names_equal() call will have gotten a match but we
|
|
* still treat it correctly.
|
|
*/
|
|
goto found_it2;
|
|
}
|
|
/*
|
|
* We have finished with this index buffer without success. Check for
|
|
* the presence of a child node.
|
|
*/
|
|
if (ie->flags & INDEX_ENTRY_NODE) {
|
|
if ((ia->index.flags & NODE_MASK) == LEAF_NODE) {
|
|
ntfs_error(sb, "Index entry with child node found in "
|
|
"a leaf node in directory inode 0x%lx.",
|
|
dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/* Child node present, descend into it. */
|
|
old_vcn = vcn;
|
|
vcn = sle64_to_cpup((u8*)ie + le16_to_cpu(ie->length) - 8);
|
|
if (vcn >= 0) {
|
|
/* If vcn is in the same page cache page as old_vcn we
|
|
* recycle the mapped page. */
|
|
if (old_vcn << vol->cluster_size_bits >>
|
|
PAGE_CACHE_SHIFT == vcn <<
|
|
vol->cluster_size_bits >>
|
|
PAGE_CACHE_SHIFT)
|
|
goto fast_descend_into_child_node;
|
|
unlock_page(page);
|
|
ntfs_unmap_page(page);
|
|
goto descend_into_child_node;
|
|
}
|
|
ntfs_error(sb, "Negative child node vcn in directory inode "
|
|
"0x%lx.", dir_ni->mft_no);
|
|
goto unm_err_out;
|
|
}
|
|
/* No child node, return -ENOENT. */
|
|
ntfs_debug("Entry not found.");
|
|
err = -ENOENT;
|
|
unm_err_out:
|
|
unlock_page(page);
|
|
ntfs_unmap_page(page);
|
|
err_out:
|
|
if (!err)
|
|
err = -EIO;
|
|
if (ctx)
|
|
ntfs_attr_put_search_ctx(ctx);
|
|
if (m)
|
|
unmap_mft_record(dir_ni);
|
|
return ERR_MREF(err);
|
|
dir_err_out:
|
|
ntfs_error(sb, "Corrupt directory. Aborting lookup.");
|
|
goto err_out;
|
|
}
|
|
|
|
#endif
|
|
|
|
/**
|
|
* ntfs_filldir - ntfs specific filldir method
|
|
* @vol: current ntfs volume
|
|
* @ndir: ntfs inode of current directory
|
|
* @ia_page: page in which the index allocation buffer @ie is in resides
|
|
* @ie: current index entry
|
|
* @name: buffer to use for the converted name
|
|
* @actor: what to feed the entries to
|
|
*
|
|
* Convert the Unicode @name to the loaded NLS and pass it to the @filldir
|
|
* callback.
|
|
*
|
|
* If @ia_page is not NULL it is the locked page containing the index
|
|
* allocation block containing the index entry @ie.
|
|
*
|
|
* Note, we drop (and then reacquire) the page lock on @ia_page across the
|
|
* @filldir() call otherwise we would deadlock with NFSd when it calls ->lookup
|
|
* since ntfs_lookup() will lock the same page. As an optimization, we do not
|
|
* retake the lock if we are returning a non-zero value as ntfs_readdir()
|
|
* would need to drop the lock immediately anyway.
|
|
*/
|
|
static inline int ntfs_filldir(ntfs_volume *vol,
|
|
ntfs_inode *ndir, struct page *ia_page, INDEX_ENTRY *ie,
|
|
u8 *name, struct dir_context *actor)
|
|
{
|
|
unsigned long mref;
|
|
int name_len;
|
|
unsigned dt_type;
|
|
FILE_NAME_TYPE_FLAGS name_type;
|
|
|
|
name_type = ie->key.file_name.file_name_type;
|
|
if (name_type == FILE_NAME_DOS) {
|
|
ntfs_debug("Skipping DOS name space entry.");
|
|
return 0;
|
|
}
|
|
if (MREF_LE(ie->data.dir.indexed_file) == FILE_root) {
|
|
ntfs_debug("Skipping root directory self reference entry.");
|
|
return 0;
|
|
}
|
|
if (MREF_LE(ie->data.dir.indexed_file) < FILE_first_user &&
|
|
!NVolShowSystemFiles(vol)) {
|
|
ntfs_debug("Skipping system file.");
|
|
return 0;
|
|
}
|
|
name_len = ntfs_ucstonls(vol, (ntfschar*)&ie->key.file_name.file_name,
|
|
ie->key.file_name.file_name_length, &name,
|
|
NTFS_MAX_NAME_LEN * NLS_MAX_CHARSET_SIZE + 1);
|
|
if (name_len <= 0) {
|
|
ntfs_warning(vol->sb, "Skipping unrepresentable inode 0x%llx.",
|
|
(long long)MREF_LE(ie->data.dir.indexed_file));
|
|
return 0;
|
|
}
|
|
if (ie->key.file_name.file_attributes &
|
|
FILE_ATTR_DUP_FILE_NAME_INDEX_PRESENT)
|
|
dt_type = DT_DIR;
|
|
else
|
|
dt_type = DT_REG;
|
|
mref = MREF_LE(ie->data.dir.indexed_file);
|
|
/*
|
|
* Drop the page lock otherwise we deadlock with NFS when it calls
|
|
* ->lookup since ntfs_lookup() will lock the same page.
|
|
*/
|
|
if (ia_page)
|
|
unlock_page(ia_page);
|
|
ntfs_debug("Calling filldir for %s with len %i, fpos 0x%llx, inode "
|
|
"0x%lx, DT_%s.", name, name_len, actor->pos, mref,
|
|
dt_type == DT_DIR ? "DIR" : "REG");
|
|
if (!dir_emit(actor, name, name_len, mref, dt_type))
|
|
return 1;
|
|
/* Relock the page but not if we are aborting ->readdir. */
|
|
if (ia_page)
|
|
lock_page(ia_page);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* We use the same basic approach as the old NTFS driver, i.e. we parse the
|
|
* index root entries and then the index allocation entries that are marked
|
|
* as in use in the index bitmap.
|
|
*
|
|
* While this will return the names in random order this doesn't matter for
|
|
* ->readdir but OTOH results in a faster ->readdir.
|
|
*
|
|
* VFS calls ->readdir without BKL but with i_mutex held. This protects the VFS
|
|
* parts (e.g. ->f_pos and ->i_size, and it also protects against directory
|
|
* modifications).
|
|
*
|
|
* Locking: - Caller must hold i_mutex on the directory.
|
|
* - Each page cache page in the index allocation mapping must be
|
|
* locked whilst being accessed otherwise we may find a corrupt
|
|
* page due to it being under ->writepage at the moment which
|
|
* applies the mst protection fixups before writing out and then
|
|
* removes them again after the write is complete after which it
|
|
* unlocks the page.
|
|
*/
|
|
static int ntfs_readdir(struct file *file, struct dir_context *actor)
|
|
{
|
|
s64 ia_pos, ia_start, prev_ia_pos, bmp_pos;
|
|
loff_t i_size;
|
|
struct inode *bmp_vi, *vdir = file_inode(file);
|
|
struct super_block *sb = vdir->i_sb;
|
|
ntfs_inode *ndir = NTFS_I(vdir);
|
|
ntfs_volume *vol = NTFS_SB(sb);
|
|
MFT_RECORD *m;
|
|
INDEX_ROOT *ir = NULL;
|
|
INDEX_ENTRY *ie;
|
|
INDEX_ALLOCATION *ia;
|
|
u8 *name = NULL;
|
|
int rc, err, ir_pos, cur_bmp_pos;
|
|
struct address_space *ia_mapping, *bmp_mapping;
|
|
struct page *bmp_page = NULL, *ia_page = NULL;
|
|
u8 *kaddr, *bmp, *index_end;
|
|
ntfs_attr_search_ctx *ctx;
|
|
|
|
ntfs_debug("Entering for inode 0x%lx, fpos 0x%llx.",
|
|
vdir->i_ino, actor->pos);
|
|
rc = err = 0;
|
|
/* Are we at end of dir yet? */
|
|
i_size = i_size_read(vdir);
|
|
if (actor->pos >= i_size + vol->mft_record_size)
|
|
return 0;
|
|
/* Emulate . and .. for all directories. */
|
|
if (!dir_emit_dots(file, actor))
|
|
return 0;
|
|
m = NULL;
|
|
ctx = NULL;
|
|
/*
|
|
* Allocate a buffer to store the current name being processed
|
|
* converted to format determined by current NLS.
|
|
*/
|
|
name = kmalloc(NTFS_MAX_NAME_LEN * NLS_MAX_CHARSET_SIZE + 1, GFP_NOFS);
|
|
if (unlikely(!name)) {
|
|
err = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
/* Are we jumping straight into the index allocation attribute? */
|
|
if (actor->pos >= vol->mft_record_size)
|
|
goto skip_index_root;
|
|
/* Get hold of the mft record for the directory. */
|
|
m = map_mft_record(ndir);
|
|
if (IS_ERR(m)) {
|
|
err = PTR_ERR(m);
|
|
m = NULL;
|
|
goto err_out;
|
|
}
|
|
ctx = ntfs_attr_get_search_ctx(ndir, m);
|
|
if (unlikely(!ctx)) {
|
|
err = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
/* Get the offset into the index root attribute. */
|
|
ir_pos = (s64)actor->pos;
|
|
/* Find the index root attribute in the mft record. */
|
|
err = ntfs_attr_lookup(AT_INDEX_ROOT, I30, 4, CASE_SENSITIVE, 0, NULL,
|
|
0, ctx);
|
|
if (unlikely(err)) {
|
|
ntfs_error(sb, "Index root attribute missing in directory "
|
|
"inode 0x%lx.", vdir->i_ino);
|
|
goto err_out;
|
|
}
|
|
/*
|
|
* Copy the index root attribute value to a buffer so that we can put
|
|
* the search context and unmap the mft record before calling the
|
|
* filldir() callback. We need to do this because of NFSd which calls
|
|
* ->lookup() from its filldir callback() and this causes NTFS to
|
|
* deadlock as ntfs_lookup() maps the mft record of the directory and
|
|
* we have got it mapped here already. The only solution is for us to
|
|
* unmap the mft record here so that a call to ntfs_lookup() is able to
|
|
* map the mft record without deadlocking.
|
|
*/
|
|
rc = le32_to_cpu(ctx->attr->data.resident.value_length);
|
|
ir = kmalloc(rc, GFP_NOFS);
|
|
if (unlikely(!ir)) {
|
|
err = -ENOMEM;
|
|
goto err_out;
|
|
}
|
|
/* Copy the index root value (it has been verified in read_inode). */
|
|
memcpy(ir, (u8*)ctx->attr +
|
|
le16_to_cpu(ctx->attr->data.resident.value_offset), rc);
|
|
ntfs_attr_put_search_ctx(ctx);
|
|
unmap_mft_record(ndir);
|
|
ctx = NULL;
|
|
m = NULL;
|
|
index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
|
|
/* The first index entry. */
|
|
ie = (INDEX_ENTRY*)((u8*)&ir->index +
|
|
le32_to_cpu(ir->index.entries_offset));
|
|
/*
|
|
* Loop until we exceed valid memory (corruption case) or until we
|
|
* reach the last entry or until filldir tells us it has had enough
|
|
* or signals an error (both covered by the rc test).
|
|
*/
|
|
for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
|
|
ntfs_debug("In index root, offset 0x%zx.", (u8*)ie - (u8*)ir);
|
|
/* Bounds checks. */
|
|
if (unlikely((u8*)ie < (u8*)ir || (u8*)ie +
|
|
sizeof(INDEX_ENTRY_HEADER) > index_end ||
|
|
(u8*)ie + le16_to_cpu(ie->key_length) >
|
|
index_end))
|
|
goto err_out;
|
|
/* The last entry cannot contain a name. */
|
|
if (ie->flags & INDEX_ENTRY_END)
|
|
break;
|
|
/* Skip index root entry if continuing previous readdir. */
|
|
if (ir_pos > (u8*)ie - (u8*)ir)
|
|
continue;
|
|
/* Advance the position even if going to skip the entry. */
|
|
actor->pos = (u8*)ie - (u8*)ir;
|
|
/* Submit the name to the filldir callback. */
|
|
rc = ntfs_filldir(vol, ndir, NULL, ie, name, actor);
|
|
if (rc) {
|
|
kfree(ir);
|
|
goto abort;
|
|
}
|
|
}
|
|
/* We are done with the index root and can free the buffer. */
|
|
kfree(ir);
|
|
ir = NULL;
|
|
/* If there is no index allocation attribute we are finished. */
|
|
if (!NInoIndexAllocPresent(ndir))
|
|
goto EOD;
|
|
/* Advance fpos to the beginning of the index allocation. */
|
|
actor->pos = vol->mft_record_size;
|
|
skip_index_root:
|
|
kaddr = NULL;
|
|
prev_ia_pos = -1LL;
|
|
/* Get the offset into the index allocation attribute. */
|
|
ia_pos = (s64)actor->pos - vol->mft_record_size;
|
|
ia_mapping = vdir->i_mapping;
|
|
ntfs_debug("Inode 0x%lx, getting index bitmap.", vdir->i_ino);
|
|
bmp_vi = ntfs_attr_iget(vdir, AT_BITMAP, I30, 4);
|
|
if (IS_ERR(bmp_vi)) {
|
|
ntfs_error(sb, "Failed to get bitmap attribute.");
|
|
err = PTR_ERR(bmp_vi);
|
|
goto err_out;
|
|
}
|
|
bmp_mapping = bmp_vi->i_mapping;
|
|
/* Get the starting bitmap bit position and sanity check it. */
|
|
bmp_pos = ia_pos >> ndir->itype.index.block_size_bits;
|
|
if (unlikely(bmp_pos >> 3 >= i_size_read(bmp_vi))) {
|
|
ntfs_error(sb, "Current index allocation position exceeds "
|
|
"index bitmap size.");
|
|
goto iput_err_out;
|
|
}
|
|
/* Get the starting bit position in the current bitmap page. */
|
|
cur_bmp_pos = bmp_pos & ((PAGE_CACHE_SIZE * 8) - 1);
|
|
bmp_pos &= ~(u64)((PAGE_CACHE_SIZE * 8) - 1);
|
|
get_next_bmp_page:
|
|
ntfs_debug("Reading bitmap with page index 0x%llx, bit ofs 0x%llx",
|
|
(unsigned long long)bmp_pos >> (3 + PAGE_CACHE_SHIFT),
|
|
(unsigned long long)bmp_pos &
|
|
(unsigned long long)((PAGE_CACHE_SIZE * 8) - 1));
|
|
bmp_page = ntfs_map_page(bmp_mapping,
|
|
bmp_pos >> (3 + PAGE_CACHE_SHIFT));
|
|
if (IS_ERR(bmp_page)) {
|
|
ntfs_error(sb, "Reading index bitmap failed.");
|
|
err = PTR_ERR(bmp_page);
|
|
bmp_page = NULL;
|
|
goto iput_err_out;
|
|
}
|
|
bmp = (u8*)page_address(bmp_page);
|
|
/* Find next index block in use. */
|
|
while (!(bmp[cur_bmp_pos >> 3] & (1 << (cur_bmp_pos & 7)))) {
|
|
find_next_index_buffer:
|
|
cur_bmp_pos++;
|
|
/*
|
|
* If we have reached the end of the bitmap page, get the next
|
|
* page, and put away the old one.
|
|
*/
|
|
if (unlikely((cur_bmp_pos >> 3) >= PAGE_CACHE_SIZE)) {
|
|
ntfs_unmap_page(bmp_page);
|
|
bmp_pos += PAGE_CACHE_SIZE * 8;
|
|
cur_bmp_pos = 0;
|
|
goto get_next_bmp_page;
|
|
}
|
|
/* If we have reached the end of the bitmap, we are done. */
|
|
if (unlikely(((bmp_pos + cur_bmp_pos) >> 3) >= i_size))
|
|
goto unm_EOD;
|
|
ia_pos = (bmp_pos + cur_bmp_pos) <<
|
|
ndir->itype.index.block_size_bits;
|
|
}
|
|
ntfs_debug("Handling index buffer 0x%llx.",
|
|
(unsigned long long)bmp_pos + cur_bmp_pos);
|
|
/* If the current index buffer is in the same page we reuse the page. */
|
|
if ((prev_ia_pos & (s64)PAGE_CACHE_MASK) !=
|
|
(ia_pos & (s64)PAGE_CACHE_MASK)) {
|
|
prev_ia_pos = ia_pos;
|
|
if (likely(ia_page != NULL)) {
|
|
unlock_page(ia_page);
|
|
ntfs_unmap_page(ia_page);
|
|
}
|
|
/*
|
|
* Map the page cache page containing the current ia_pos,
|
|
* reading it from disk if necessary.
|
|
*/
|
|
ia_page = ntfs_map_page(ia_mapping, ia_pos >> PAGE_CACHE_SHIFT);
|
|
if (IS_ERR(ia_page)) {
|
|
ntfs_error(sb, "Reading index allocation data failed.");
|
|
err = PTR_ERR(ia_page);
|
|
ia_page = NULL;
|
|
goto err_out;
|
|
}
|
|
lock_page(ia_page);
|
|
kaddr = (u8*)page_address(ia_page);
|
|
}
|
|
/* Get the current index buffer. */
|
|
ia = (INDEX_ALLOCATION*)(kaddr + (ia_pos & ~PAGE_CACHE_MASK &
|
|
~(s64)(ndir->itype.index.block_size - 1)));
|
|
/* Bounds checks. */
|
|
if (unlikely((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE)) {
|
|
ntfs_error(sb, "Out of bounds check failed. Corrupt directory "
|
|
"inode 0x%lx or driver bug.", vdir->i_ino);
|
|
goto err_out;
|
|
}
|
|
/* Catch multi sector transfer fixup errors. */
|
|
if (unlikely(!ntfs_is_indx_record(ia->magic))) {
|
|
ntfs_error(sb, "Directory index record with vcn 0x%llx is "
|
|
"corrupt. Corrupt inode 0x%lx. Run chkdsk.",
|
|
(unsigned long long)ia_pos >>
|
|
ndir->itype.index.vcn_size_bits, vdir->i_ino);
|
|
goto err_out;
|
|
}
|
|
if (unlikely(sle64_to_cpu(ia->index_block_vcn) != (ia_pos &
|
|
~(s64)(ndir->itype.index.block_size - 1)) >>
|
|
ndir->itype.index.vcn_size_bits)) {
|
|
ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is "
|
|
"different from expected VCN (0x%llx). "
|
|
"Directory inode 0x%lx is corrupt or driver "
|
|
"bug. ", (unsigned long long)
|
|
sle64_to_cpu(ia->index_block_vcn),
|
|
(unsigned long long)ia_pos >>
|
|
ndir->itype.index.vcn_size_bits, vdir->i_ino);
|
|
goto err_out;
|
|
}
|
|
if (unlikely(le32_to_cpu(ia->index.allocated_size) + 0x18 !=
|
|
ndir->itype.index.block_size)) {
|
|
ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode "
|
|
"0x%lx has a size (%u) differing from the "
|
|
"directory specified size (%u). Directory "
|
|
"inode is corrupt or driver bug.",
|
|
(unsigned long long)ia_pos >>
|
|
ndir->itype.index.vcn_size_bits, vdir->i_ino,
|
|
le32_to_cpu(ia->index.allocated_size) + 0x18,
|
|
ndir->itype.index.block_size);
|
|
goto err_out;
|
|
}
|
|
index_end = (u8*)ia + ndir->itype.index.block_size;
|
|
if (unlikely(index_end > kaddr + PAGE_CACHE_SIZE)) {
|
|
ntfs_error(sb, "Index buffer (VCN 0x%llx) of directory inode "
|
|
"0x%lx crosses page boundary. Impossible! "
|
|
"Cannot access! This is probably a bug in the "
|
|
"driver.", (unsigned long long)ia_pos >>
|
|
ndir->itype.index.vcn_size_bits, vdir->i_ino);
|
|
goto err_out;
|
|
}
|
|
ia_start = ia_pos & ~(s64)(ndir->itype.index.block_size - 1);
|
|
index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length);
|
|
if (unlikely(index_end > (u8*)ia + ndir->itype.index.block_size)) {
|
|
ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of directory "
|
|
"inode 0x%lx exceeds maximum size.",
|
|
(unsigned long long)ia_pos >>
|
|
ndir->itype.index.vcn_size_bits, vdir->i_ino);
|
|
goto err_out;
|
|
}
|
|
/* The first index entry in this index buffer. */
|
|
ie = (INDEX_ENTRY*)((u8*)&ia->index +
|
|
le32_to_cpu(ia->index.entries_offset));
|
|
/*
|
|
* Loop until we exceed valid memory (corruption case) or until we
|
|
* reach the last entry or until filldir tells us it has had enough
|
|
* or signals an error (both covered by the rc test).
|
|
*/
|
|
for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
|
|
ntfs_debug("In index allocation, offset 0x%llx.",
|
|
(unsigned long long)ia_start +
|
|
(unsigned long long)((u8*)ie - (u8*)ia));
|
|
/* Bounds checks. */
|
|
if (unlikely((u8*)ie < (u8*)ia || (u8*)ie +
|
|
sizeof(INDEX_ENTRY_HEADER) > index_end ||
|
|
(u8*)ie + le16_to_cpu(ie->key_length) >
|
|
index_end))
|
|
goto err_out;
|
|
/* The last entry cannot contain a name. */
|
|
if (ie->flags & INDEX_ENTRY_END)
|
|
break;
|
|
/* Skip index block entry if continuing previous readdir. */
|
|
if (ia_pos - ia_start > (u8*)ie - (u8*)ia)
|
|
continue;
|
|
/* Advance the position even if going to skip the entry. */
|
|
actor->pos = (u8*)ie - (u8*)ia +
|
|
(sle64_to_cpu(ia->index_block_vcn) <<
|
|
ndir->itype.index.vcn_size_bits) +
|
|
vol->mft_record_size;
|
|
/*
|
|
* Submit the name to the @filldir callback. Note,
|
|
* ntfs_filldir() drops the lock on @ia_page but it retakes it
|
|
* before returning, unless a non-zero value is returned in
|
|
* which case the page is left unlocked.
|
|
*/
|
|
rc = ntfs_filldir(vol, ndir, ia_page, ie, name, actor);
|
|
if (rc) {
|
|
/* @ia_page is already unlocked in this case. */
|
|
ntfs_unmap_page(ia_page);
|
|
ntfs_unmap_page(bmp_page);
|
|
iput(bmp_vi);
|
|
goto abort;
|
|
}
|
|
}
|
|
goto find_next_index_buffer;
|
|
unm_EOD:
|
|
if (ia_page) {
|
|
unlock_page(ia_page);
|
|
ntfs_unmap_page(ia_page);
|
|
}
|
|
ntfs_unmap_page(bmp_page);
|
|
iput(bmp_vi);
|
|
EOD:
|
|
/* We are finished, set fpos to EOD. */
|
|
actor->pos = i_size + vol->mft_record_size;
|
|
abort:
|
|
kfree(name);
|
|
return 0;
|
|
err_out:
|
|
if (bmp_page) {
|
|
ntfs_unmap_page(bmp_page);
|
|
iput_err_out:
|
|
iput(bmp_vi);
|
|
}
|
|
if (ia_page) {
|
|
unlock_page(ia_page);
|
|
ntfs_unmap_page(ia_page);
|
|
}
|
|
kfree(ir);
|
|
kfree(name);
|
|
if (ctx)
|
|
ntfs_attr_put_search_ctx(ctx);
|
|
if (m)
|
|
unmap_mft_record(ndir);
|
|
if (!err)
|
|
err = -EIO;
|
|
ntfs_debug("Failed. Returning error code %i.", -err);
|
|
return err;
|
|
}
|
|
|
|
/**
|
|
* ntfs_dir_open - called when an inode is about to be opened
|
|
* @vi: inode to be opened
|
|
* @filp: file structure describing the inode
|
|
*
|
|
* Limit directory size to the page cache limit on architectures where unsigned
|
|
* long is 32-bits. This is the most we can do for now without overflowing the
|
|
* page cache page index. Doing it this way means we don't run into problems
|
|
* because of existing too large directories. It would be better to allow the
|
|
* user to read the accessible part of the directory but I doubt very much
|
|
* anyone is going to hit this check on a 32-bit architecture, so there is no
|
|
* point in adding the extra complexity required to support this.
|
|
*
|
|
* On 64-bit architectures, the check is hopefully optimized away by the
|
|
* compiler.
|
|
*/
|
|
static int ntfs_dir_open(struct inode *vi, struct file *filp)
|
|
{
|
|
if (sizeof(unsigned long) < 8) {
|
|
if (i_size_read(vi) > MAX_LFS_FILESIZE)
|
|
return -EFBIG;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
#ifdef NTFS_RW
|
|
|
|
/**
|
|
* ntfs_dir_fsync - sync a directory to disk
|
|
* @filp: directory to be synced
|
|
* @dentry: dentry describing the directory to sync
|
|
* @datasync: if non-zero only flush user data and not metadata
|
|
*
|
|
* Data integrity sync of a directory to disk. Used for fsync, fdatasync, and
|
|
* msync system calls. This function is based on file.c::ntfs_file_fsync().
|
|
*
|
|
* Write the mft record and all associated extent mft records as well as the
|
|
* $INDEX_ALLOCATION and $BITMAP attributes and then sync the block device.
|
|
*
|
|
* If @datasync is true, we do not wait on the inode(s) to be written out
|
|
* but we always wait on the page cache pages to be written out.
|
|
*
|
|
* Note: In the past @filp could be NULL so we ignore it as we don't need it
|
|
* anyway.
|
|
*
|
|
* Locking: Caller must hold i_mutex on the inode.
|
|
*
|
|
* TODO: We should probably also write all attribute/index inodes associated
|
|
* with this inode but since we have no simple way of getting to them we ignore
|
|
* this problem for now. We do write the $BITMAP attribute if it is present
|
|
* which is the important one for a directory so things are not too bad.
|
|
*/
|
|
static int ntfs_dir_fsync(struct file *filp, loff_t start, loff_t end,
|
|
int datasync)
|
|
{
|
|
struct inode *bmp_vi, *vi = filp->f_mapping->host;
|
|
int err, ret;
|
|
ntfs_attr na;
|
|
|
|
ntfs_debug("Entering for inode 0x%lx.", vi->i_ino);
|
|
|
|
err = filemap_write_and_wait_range(vi->i_mapping, start, end);
|
|
if (err)
|
|
return err;
|
|
mutex_lock(&vi->i_mutex);
|
|
|
|
BUG_ON(!S_ISDIR(vi->i_mode));
|
|
/* If the bitmap attribute inode is in memory sync it, too. */
|
|
na.mft_no = vi->i_ino;
|
|
na.type = AT_BITMAP;
|
|
na.name = I30;
|
|
na.name_len = 4;
|
|
bmp_vi = ilookup5(vi->i_sb, vi->i_ino, (test_t)ntfs_test_inode, &na);
|
|
if (bmp_vi) {
|
|
write_inode_now(bmp_vi, !datasync);
|
|
iput(bmp_vi);
|
|
}
|
|
ret = __ntfs_write_inode(vi, 1);
|
|
write_inode_now(vi, !datasync);
|
|
err = sync_blockdev(vi->i_sb->s_bdev);
|
|
if (unlikely(err && !ret))
|
|
ret = err;
|
|
if (likely(!ret))
|
|
ntfs_debug("Done.");
|
|
else
|
|
ntfs_warning(vi->i_sb, "Failed to f%ssync inode 0x%lx. Error "
|
|
"%u.", datasync ? "data" : "", vi->i_ino, -ret);
|
|
mutex_unlock(&vi->i_mutex);
|
|
return ret;
|
|
}
|
|
|
|
#endif /* NTFS_RW */
|
|
|
|
const struct file_operations ntfs_dir_ops = {
|
|
.llseek = generic_file_llseek, /* Seek inside directory. */
|
|
.read = generic_read_dir, /* Return -EISDIR. */
|
|
.iterate = ntfs_readdir, /* Read directory contents. */
|
|
#ifdef NTFS_RW
|
|
.fsync = ntfs_dir_fsync, /* Sync a directory to disk. */
|
|
/*.aio_fsync = ,*/ /* Sync all outstanding async
|
|
i/o operations on a kiocb. */
|
|
#endif /* NTFS_RW */
|
|
/*.ioctl = ,*/ /* Perform function on the
|
|
mounted filesystem. */
|
|
.open = ntfs_dir_open, /* Open directory. */
|
|
};
|