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62 |
marcus.erl |
/*
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| 2 |
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* index.c - NTFS kernel index handling. Part of the Linux-NTFS project.
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*
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* Copyright (c) 2004-2005 Anton Altaparmakov
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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 "aops.h"
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#include "collate.h"
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| 24 |
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#include "debug.h"
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#include "index.h"
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#include "ntfs.h"
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| 28 |
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/**
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* ntfs_index_ctx_get - allocate and initialize a new index context
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* @idx_ni: ntfs index inode with which to initialize the context
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*
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* Allocate a new index context, initialize it with @idx_ni and return it.
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* Return NULL if allocation failed.
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*
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* Locking: Caller must hold i_mutex on the index inode.
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*/
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ntfs_index_context *ntfs_index_ctx_get(ntfs_inode *idx_ni)
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| 38 |
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{
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| 39 |
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ntfs_index_context *ictx;
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| 40 |
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| 41 |
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ictx = kmem_cache_alloc(ntfs_index_ctx_cache, GFP_NOFS);
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| 42 |
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if (ictx)
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| 43 |
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*ictx = (ntfs_index_context){ .idx_ni = idx_ni };
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| 44 |
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return ictx;
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| 45 |
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}
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| 46 |
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| 47 |
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/**
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| 48 |
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* ntfs_index_ctx_put - release an index context
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| 49 |
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* @ictx: index context to free
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| 50 |
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*
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* Release the index context @ictx, releasing all associated resources.
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*
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* Locking: Caller must hold i_mutex on the index inode.
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*/
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| 55 |
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void ntfs_index_ctx_put(ntfs_index_context *ictx)
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{
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| 57 |
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if (ictx->entry) {
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| 58 |
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if (ictx->is_in_root) {
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if (ictx->actx)
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| 60 |
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ntfs_attr_put_search_ctx(ictx->actx);
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| 61 |
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if (ictx->base_ni)
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| 62 |
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unmap_mft_record(ictx->base_ni);
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| 63 |
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} else {
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| 64 |
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struct page *page = ictx->page;
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| 65 |
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if (page) {
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| 66 |
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BUG_ON(!PageLocked(page));
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| 67 |
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unlock_page(page);
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| 68 |
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ntfs_unmap_page(page);
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| 69 |
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}
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| 70 |
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}
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| 71 |
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}
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| 72 |
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kmem_cache_free(ntfs_index_ctx_cache, ictx);
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| 73 |
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return;
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| 74 |
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}
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| 76 |
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/**
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| 77 |
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* ntfs_index_lookup - find a key in an index and return its index entry
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* @key: [IN] key for which to search in the index
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* @key_len: [IN] length of @key in bytes
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| 80 |
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* @ictx: [IN/OUT] context describing the index and the returned entry
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*
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| 82 |
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* Before calling ntfs_index_lookup(), @ictx must have been obtained from a
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| 83 |
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* call to ntfs_index_ctx_get().
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| 84 |
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*
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| 85 |
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* Look for the @key in the index specified by the index lookup context @ictx.
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* ntfs_index_lookup() walks the contents of the index looking for the @key.
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*
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* If the @key is found in the index, 0 is returned and @ictx is setup to
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| 89 |
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* describe the index entry containing the matching @key. @ictx->entry is the
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| 90 |
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* index entry and @ictx->data and @ictx->data_len are the index entry data and
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| 91 |
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* its length in bytes, respectively.
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| 92 |
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*
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| 93 |
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* If the @key is not found in the index, -ENOENT is returned and @ictx is
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| 94 |
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* setup to describe the index entry whose key collates immediately after the
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* search @key, i.e. this is the position in the index at which an index entry
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| 96 |
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* with a key of @key would need to be inserted.
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*
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| 98 |
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* If an error occurs return the negative error code and @ictx is left
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* untouched.
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| 100 |
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*
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| 101 |
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* When finished with the entry and its data, call ntfs_index_ctx_put() to free
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| 102 |
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* the context and other associated resources.
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| 103 |
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*
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| 104 |
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* If the index entry was modified, call flush_dcache_index_entry_page()
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| 105 |
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* immediately after the modification and either ntfs_index_entry_mark_dirty()
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* or ntfs_index_entry_write() before the call to ntfs_index_ctx_put() to
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| 107 |
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* ensure that the changes are written to disk.
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*
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| 109 |
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* Locking: - Caller must hold i_mutex on the index inode.
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| 110 |
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* - Each page cache page in the index allocation mapping must be
|
| 111 |
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* locked whilst being accessed otherwise we may find a corrupt
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| 112 |
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* page due to it being under ->writepage at the moment which
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| 113 |
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* applies the mst protection fixups before writing out and then
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| 114 |
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* removes them again after the write is complete after which it
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| 115 |
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* unlocks the page.
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| 116 |
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*/
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| 117 |
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int ntfs_index_lookup(const void *key, const int key_len,
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| 118 |
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ntfs_index_context *ictx)
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{
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| 120 |
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VCN vcn, old_vcn;
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| 121 |
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ntfs_inode *idx_ni = ictx->idx_ni;
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ntfs_volume *vol = idx_ni->vol;
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| 123 |
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struct super_block *sb = vol->sb;
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| 124 |
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ntfs_inode *base_ni = idx_ni->ext.base_ntfs_ino;
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| 125 |
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MFT_RECORD *m;
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| 126 |
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INDEX_ROOT *ir;
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| 127 |
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INDEX_ENTRY *ie;
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| 128 |
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INDEX_ALLOCATION *ia;
|
| 129 |
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u8 *index_end, *kaddr;
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| 130 |
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ntfs_attr_search_ctx *actx;
|
| 131 |
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struct address_space *ia_mapping;
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| 132 |
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struct page *page;
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| 133 |
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int rc, err = 0;
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| 134 |
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| 135 |
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ntfs_debug("Entering.");
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| 136 |
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BUG_ON(!NInoAttr(idx_ni));
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| 137 |
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BUG_ON(idx_ni->type != AT_INDEX_ALLOCATION);
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| 138 |
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BUG_ON(idx_ni->nr_extents != -1);
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| 139 |
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BUG_ON(!base_ni);
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| 140 |
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BUG_ON(!key);
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| 141 |
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BUG_ON(key_len <= 0);
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| 142 |
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if (!ntfs_is_collation_rule_supported(
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| 143 |
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idx_ni->itype.index.collation_rule)) {
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| 144 |
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ntfs_error(sb, "Index uses unsupported collation rule 0x%x. "
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| 145 |
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"Aborting lookup.", le32_to_cpu(
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| 146 |
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idx_ni->itype.index.collation_rule));
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| 147 |
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return -EOPNOTSUPP;
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| 148 |
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}
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| 149 |
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/* Get hold of the mft record for the index inode. */
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| 150 |
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m = map_mft_record(base_ni);
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| 151 |
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if (IS_ERR(m)) {
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| 152 |
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ntfs_error(sb, "map_mft_record() failed with error code %ld.",
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| 153 |
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-PTR_ERR(m));
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| 154 |
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return PTR_ERR(m);
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| 155 |
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}
|
| 156 |
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actx = ntfs_attr_get_search_ctx(base_ni, m);
|
| 157 |
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if (unlikely(!actx)) {
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| 158 |
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err = -ENOMEM;
|
| 159 |
|
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goto err_out;
|
| 160 |
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|
}
|
| 161 |
|
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/* Find the index root attribute in the mft record. */
|
| 162 |
|
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err = ntfs_attr_lookup(AT_INDEX_ROOT, idx_ni->name, idx_ni->name_len,
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| 163 |
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CASE_SENSITIVE, 0, NULL, 0, actx);
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| 164 |
|
|
if (unlikely(err)) {
|
| 165 |
|
|
if (err == -ENOENT) {
|
| 166 |
|
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ntfs_error(sb, "Index root attribute missing in inode "
|
| 167 |
|
|
"0x%lx.", idx_ni->mft_no);
|
| 168 |
|
|
err = -EIO;
|
| 169 |
|
|
}
|
| 170 |
|
|
goto err_out;
|
| 171 |
|
|
}
|
| 172 |
|
|
/* Get to the index root value (it has been verified in read_inode). */
|
| 173 |
|
|
ir = (INDEX_ROOT*)((u8*)actx->attr +
|
| 174 |
|
|
le16_to_cpu(actx->attr->data.resident.value_offset));
|
| 175 |
|
|
index_end = (u8*)&ir->index + le32_to_cpu(ir->index.index_length);
|
| 176 |
|
|
/* The first index entry. */
|
| 177 |
|
|
ie = (INDEX_ENTRY*)((u8*)&ir->index +
|
| 178 |
|
|
le32_to_cpu(ir->index.entries_offset));
|
| 179 |
|
|
/*
|
| 180 |
|
|
* Loop until we exceed valid memory (corruption case) or until we
|
| 181 |
|
|
* reach the last entry.
|
| 182 |
|
|
*/
|
| 183 |
|
|
for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
|
| 184 |
|
|
/* Bounds checks. */
|
| 185 |
|
|
if ((u8*)ie < (u8*)actx->mrec || (u8*)ie +
|
| 186 |
|
|
sizeof(INDEX_ENTRY_HEADER) > index_end ||
|
| 187 |
|
|
(u8*)ie + le16_to_cpu(ie->length) > index_end)
|
| 188 |
|
|
goto idx_err_out;
|
| 189 |
|
|
/*
|
| 190 |
|
|
* The last entry cannot contain a key. It can however contain
|
| 191 |
|
|
* a pointer to a child node in the B+tree so we just break out.
|
| 192 |
|
|
*/
|
| 193 |
|
|
if (ie->flags & INDEX_ENTRY_END)
|
| 194 |
|
|
break;
|
| 195 |
|
|
/* Further bounds checks. */
|
| 196 |
|
|
if ((u32)sizeof(INDEX_ENTRY_HEADER) +
|
| 197 |
|
|
le16_to_cpu(ie->key_length) >
|
| 198 |
|
|
le16_to_cpu(ie->data.vi.data_offset) ||
|
| 199 |
|
|
(u32)le16_to_cpu(ie->data.vi.data_offset) +
|
| 200 |
|
|
le16_to_cpu(ie->data.vi.data_length) >
|
| 201 |
|
|
le16_to_cpu(ie->length))
|
| 202 |
|
|
goto idx_err_out;
|
| 203 |
|
|
/* If the keys match perfectly, we setup @ictx and return 0. */
|
| 204 |
|
|
if ((key_len == le16_to_cpu(ie->key_length)) && !memcmp(key,
|
| 205 |
|
|
&ie->key, key_len)) {
|
| 206 |
|
|
ir_done:
|
| 207 |
|
|
ictx->is_in_root = true;
|
| 208 |
|
|
ictx->ir = ir;
|
| 209 |
|
|
ictx->actx = actx;
|
| 210 |
|
|
ictx->base_ni = base_ni;
|
| 211 |
|
|
ictx->ia = NULL;
|
| 212 |
|
|
ictx->page = NULL;
|
| 213 |
|
|
done:
|
| 214 |
|
|
ictx->entry = ie;
|
| 215 |
|
|
ictx->data = (u8*)ie +
|
| 216 |
|
|
le16_to_cpu(ie->data.vi.data_offset);
|
| 217 |
|
|
ictx->data_len = le16_to_cpu(ie->data.vi.data_length);
|
| 218 |
|
|
ntfs_debug("Done.");
|
| 219 |
|
|
return err;
|
| 220 |
|
|
}
|
| 221 |
|
|
/*
|
| 222 |
|
|
* Not a perfect match, need to do full blown collation so we
|
| 223 |
|
|
* know which way in the B+tree we have to go.
|
| 224 |
|
|
*/
|
| 225 |
|
|
rc = ntfs_collate(vol, idx_ni->itype.index.collation_rule, key,
|
| 226 |
|
|
key_len, &ie->key, le16_to_cpu(ie->key_length));
|
| 227 |
|
|
/*
|
| 228 |
|
|
* If @key collates before the key of the current entry, there
|
| 229 |
|
|
* is definitely no such key in this index but we might need to
|
| 230 |
|
|
* descend into the B+tree so we just break out of the loop.
|
| 231 |
|
|
*/
|
| 232 |
|
|
if (rc == -1)
|
| 233 |
|
|
break;
|
| 234 |
|
|
/*
|
| 235 |
|
|
* A match should never happen as the memcmp() call should have
|
| 236 |
|
|
* cought it, but we still treat it correctly.
|
| 237 |
|
|
*/
|
| 238 |
|
|
if (!rc)
|
| 239 |
|
|
goto ir_done;
|
| 240 |
|
|
/* The keys are not equal, continue the search. */
|
| 241 |
|
|
}
|
| 242 |
|
|
/*
|
| 243 |
|
|
* We have finished with this index without success. Check for the
|
| 244 |
|
|
* presence of a child node and if not present setup @ictx and return
|
| 245 |
|
|
* -ENOENT.
|
| 246 |
|
|
*/
|
| 247 |
|
|
if (!(ie->flags & INDEX_ENTRY_NODE)) {
|
| 248 |
|
|
ntfs_debug("Entry not found.");
|
| 249 |
|
|
err = -ENOENT;
|
| 250 |
|
|
goto ir_done;
|
| 251 |
|
|
} /* Child node present, descend into it. */
|
| 252 |
|
|
/* Consistency check: Verify that an index allocation exists. */
|
| 253 |
|
|
if (!NInoIndexAllocPresent(idx_ni)) {
|
| 254 |
|
|
ntfs_error(sb, "No index allocation attribute but index entry "
|
| 255 |
|
|
"requires one. Inode 0x%lx is corrupt or "
|
| 256 |
|
|
"driver bug.", idx_ni->mft_no);
|
| 257 |
|
|
goto err_out;
|
| 258 |
|
|
}
|
| 259 |
|
|
/* Get the starting vcn of the index_block holding the child node. */
|
| 260 |
|
|
vcn = sle64_to_cpup((sle64*)((u8*)ie + le16_to_cpu(ie->length) - 8));
|
| 261 |
|
|
ia_mapping = VFS_I(idx_ni)->i_mapping;
|
| 262 |
|
|
/*
|
| 263 |
|
|
* We are done with the index root and the mft record. Release them,
|
| 264 |
|
|
* otherwise we deadlock with ntfs_map_page().
|
| 265 |
|
|
*/
|
| 266 |
|
|
ntfs_attr_put_search_ctx(actx);
|
| 267 |
|
|
unmap_mft_record(base_ni);
|
| 268 |
|
|
m = NULL;
|
| 269 |
|
|
actx = NULL;
|
| 270 |
|
|
descend_into_child_node:
|
| 271 |
|
|
/*
|
| 272 |
|
|
* Convert vcn to index into the index allocation attribute in units
|
| 273 |
|
|
* of PAGE_CACHE_SIZE and map the page cache page, reading it from
|
| 274 |
|
|
* disk if necessary.
|
| 275 |
|
|
*/
|
| 276 |
|
|
page = ntfs_map_page(ia_mapping, vcn <<
|
| 277 |
|
|
idx_ni->itype.index.vcn_size_bits >> PAGE_CACHE_SHIFT);
|
| 278 |
|
|
if (IS_ERR(page)) {
|
| 279 |
|
|
ntfs_error(sb, "Failed to map index page, error %ld.",
|
| 280 |
|
|
-PTR_ERR(page));
|
| 281 |
|
|
err = PTR_ERR(page);
|
| 282 |
|
|
goto err_out;
|
| 283 |
|
|
}
|
| 284 |
|
|
lock_page(page);
|
| 285 |
|
|
kaddr = (u8*)page_address(page);
|
| 286 |
|
|
fast_descend_into_child_node:
|
| 287 |
|
|
/* Get to the index allocation block. */
|
| 288 |
|
|
ia = (INDEX_ALLOCATION*)(kaddr + ((vcn <<
|
| 289 |
|
|
idx_ni->itype.index.vcn_size_bits) & ~PAGE_CACHE_MASK));
|
| 290 |
|
|
/* Bounds checks. */
|
| 291 |
|
|
if ((u8*)ia < kaddr || (u8*)ia > kaddr + PAGE_CACHE_SIZE) {
|
| 292 |
|
|
ntfs_error(sb, "Out of bounds check failed. Corrupt inode "
|
| 293 |
|
|
"0x%lx or driver bug.", idx_ni->mft_no);
|
| 294 |
|
|
goto unm_err_out;
|
| 295 |
|
|
}
|
| 296 |
|
|
/* Catch multi sector transfer fixup errors. */
|
| 297 |
|
|
if (unlikely(!ntfs_is_indx_record(ia->magic))) {
|
| 298 |
|
|
ntfs_error(sb, "Index record with vcn 0x%llx is corrupt. "
|
| 299 |
|
|
"Corrupt inode 0x%lx. Run chkdsk.",
|
| 300 |
|
|
(long long)vcn, idx_ni->mft_no);
|
| 301 |
|
|
goto unm_err_out;
|
| 302 |
|
|
}
|
| 303 |
|
|
if (sle64_to_cpu(ia->index_block_vcn) != vcn) {
|
| 304 |
|
|
ntfs_error(sb, "Actual VCN (0x%llx) of index buffer is "
|
| 305 |
|
|
"different from expected VCN (0x%llx). Inode "
|
| 306 |
|
|
"0x%lx is corrupt or driver bug.",
|
| 307 |
|
|
(unsigned long long)
|
| 308 |
|
|
sle64_to_cpu(ia->index_block_vcn),
|
| 309 |
|
|
(unsigned long long)vcn, idx_ni->mft_no);
|
| 310 |
|
|
goto unm_err_out;
|
| 311 |
|
|
}
|
| 312 |
|
|
if (le32_to_cpu(ia->index.allocated_size) + 0x18 !=
|
| 313 |
|
|
idx_ni->itype.index.block_size) {
|
| 314 |
|
|
ntfs_error(sb, "Index buffer (VCN 0x%llx) of inode 0x%lx has "
|
| 315 |
|
|
"a size (%u) differing from the index "
|
| 316 |
|
|
"specified size (%u). Inode is corrupt or "
|
| 317 |
|
|
"driver bug.", (unsigned long long)vcn,
|
| 318 |
|
|
idx_ni->mft_no,
|
| 319 |
|
|
le32_to_cpu(ia->index.allocated_size) + 0x18,
|
| 320 |
|
|
idx_ni->itype.index.block_size);
|
| 321 |
|
|
goto unm_err_out;
|
| 322 |
|
|
}
|
| 323 |
|
|
index_end = (u8*)ia + idx_ni->itype.index.block_size;
|
| 324 |
|
|
if (index_end > kaddr + PAGE_CACHE_SIZE) {
|
| 325 |
|
|
ntfs_error(sb, "Index buffer (VCN 0x%llx) of inode 0x%lx "
|
| 326 |
|
|
"crosses page boundary. Impossible! Cannot "
|
| 327 |
|
|
"access! This is probably a bug in the "
|
| 328 |
|
|
"driver.", (unsigned long long)vcn,
|
| 329 |
|
|
idx_ni->mft_no);
|
| 330 |
|
|
goto unm_err_out;
|
| 331 |
|
|
}
|
| 332 |
|
|
index_end = (u8*)&ia->index + le32_to_cpu(ia->index.index_length);
|
| 333 |
|
|
if (index_end > (u8*)ia + idx_ni->itype.index.block_size) {
|
| 334 |
|
|
ntfs_error(sb, "Size of index buffer (VCN 0x%llx) of inode "
|
| 335 |
|
|
"0x%lx exceeds maximum size.",
|
| 336 |
|
|
(unsigned long long)vcn, idx_ni->mft_no);
|
| 337 |
|
|
goto unm_err_out;
|
| 338 |
|
|
}
|
| 339 |
|
|
/* The first index entry. */
|
| 340 |
|
|
ie = (INDEX_ENTRY*)((u8*)&ia->index +
|
| 341 |
|
|
le32_to_cpu(ia->index.entries_offset));
|
| 342 |
|
|
/*
|
| 343 |
|
|
* Iterate similar to above big loop but applied to index buffer, thus
|
| 344 |
|
|
* loop until we exceed valid memory (corruption case) or until we
|
| 345 |
|
|
* reach the last entry.
|
| 346 |
|
|
*/
|
| 347 |
|
|
for (;; ie = (INDEX_ENTRY*)((u8*)ie + le16_to_cpu(ie->length))) {
|
| 348 |
|
|
/* Bounds checks. */
|
| 349 |
|
|
if ((u8*)ie < (u8*)ia || (u8*)ie +
|
| 350 |
|
|
sizeof(INDEX_ENTRY_HEADER) > index_end ||
|
| 351 |
|
|
(u8*)ie + le16_to_cpu(ie->length) > index_end) {
|
| 352 |
|
|
ntfs_error(sb, "Index entry out of bounds in inode "
|
| 353 |
|
|
"0x%lx.", idx_ni->mft_no);
|
| 354 |
|
|
goto unm_err_out;
|
| 355 |
|
|
}
|
| 356 |
|
|
/*
|
| 357 |
|
|
* The last entry cannot contain a key. It can however contain
|
| 358 |
|
|
* a pointer to a child node in the B+tree so we just break out.
|
| 359 |
|
|
*/
|
| 360 |
|
|
if (ie->flags & INDEX_ENTRY_END)
|
| 361 |
|
|
break;
|
| 362 |
|
|
/* Further bounds checks. */
|
| 363 |
|
|
if ((u32)sizeof(INDEX_ENTRY_HEADER) +
|
| 364 |
|
|
le16_to_cpu(ie->key_length) >
|
| 365 |
|
|
le16_to_cpu(ie->data.vi.data_offset) ||
|
| 366 |
|
|
(u32)le16_to_cpu(ie->data.vi.data_offset) +
|
| 367 |
|
|
le16_to_cpu(ie->data.vi.data_length) >
|
| 368 |
|
|
le16_to_cpu(ie->length)) {
|
| 369 |
|
|
ntfs_error(sb, "Index entry out of bounds in inode "
|
| 370 |
|
|
"0x%lx.", idx_ni->mft_no);
|
| 371 |
|
|
goto unm_err_out;
|
| 372 |
|
|
}
|
| 373 |
|
|
/* If the keys match perfectly, we setup @ictx and return 0. */
|
| 374 |
|
|
if ((key_len == le16_to_cpu(ie->key_length)) && !memcmp(key,
|
| 375 |
|
|
&ie->key, key_len)) {
|
| 376 |
|
|
ia_done:
|
| 377 |
|
|
ictx->is_in_root = false;
|
| 378 |
|
|
ictx->actx = NULL;
|
| 379 |
|
|
ictx->base_ni = NULL;
|
| 380 |
|
|
ictx->ia = ia;
|
| 381 |
|
|
ictx->page = page;
|
| 382 |
|
|
goto done;
|
| 383 |
|
|
}
|
| 384 |
|
|
/*
|
| 385 |
|
|
* Not a perfect match, need to do full blown collation so we
|
| 386 |
|
|
* know which way in the B+tree we have to go.
|
| 387 |
|
|
*/
|
| 388 |
|
|
rc = ntfs_collate(vol, idx_ni->itype.index.collation_rule, key,
|
| 389 |
|
|
key_len, &ie->key, le16_to_cpu(ie->key_length));
|
| 390 |
|
|
/*
|
| 391 |
|
|
* If @key collates before the key of the current entry, there
|
| 392 |
|
|
* is definitely no such key in this index but we might need to
|
| 393 |
|
|
* descend into the B+tree so we just break out of the loop.
|
| 394 |
|
|
*/
|
| 395 |
|
|
if (rc == -1)
|
| 396 |
|
|
break;
|
| 397 |
|
|
/*
|
| 398 |
|
|
* A match should never happen as the memcmp() call should have
|
| 399 |
|
|
* cought it, but we still treat it correctly.
|
| 400 |
|
|
*/
|
| 401 |
|
|
if (!rc)
|
| 402 |
|
|
goto ia_done;
|
| 403 |
|
|
/* The keys are not equal, continue the search. */
|
| 404 |
|
|
}
|
| 405 |
|
|
/*
|
| 406 |
|
|
* We have finished with this index buffer without success. Check for
|
| 407 |
|
|
* the presence of a child node and if not present return -ENOENT.
|
| 408 |
|
|
*/
|
| 409 |
|
|
if (!(ie->flags & INDEX_ENTRY_NODE)) {
|
| 410 |
|
|
ntfs_debug("Entry not found.");
|
| 411 |
|
|
err = -ENOENT;
|
| 412 |
|
|
goto ia_done;
|
| 413 |
|
|
}
|
| 414 |
|
|
if ((ia->index.flags & NODE_MASK) == LEAF_NODE) {
|
| 415 |
|
|
ntfs_error(sb, "Index entry with child node found in a leaf "
|
| 416 |
|
|
"node in inode 0x%lx.", idx_ni->mft_no);
|
| 417 |
|
|
goto unm_err_out;
|
| 418 |
|
|
}
|
| 419 |
|
|
/* Child node present, descend into it. */
|
| 420 |
|
|
old_vcn = vcn;
|
| 421 |
|
|
vcn = sle64_to_cpup((sle64*)((u8*)ie + le16_to_cpu(ie->length) - 8));
|
| 422 |
|
|
if (vcn >= 0) {
|
| 423 |
|
|
/*
|
| 424 |
|
|
* If vcn is in the same page cache page as old_vcn we recycle
|
| 425 |
|
|
* the mapped page.
|
| 426 |
|
|
*/
|
| 427 |
|
|
if (old_vcn << vol->cluster_size_bits >>
|
| 428 |
|
|
PAGE_CACHE_SHIFT == vcn <<
|
| 429 |
|
|
vol->cluster_size_bits >>
|
| 430 |
|
|
PAGE_CACHE_SHIFT)
|
| 431 |
|
|
goto fast_descend_into_child_node;
|
| 432 |
|
|
unlock_page(page);
|
| 433 |
|
|
ntfs_unmap_page(page);
|
| 434 |
|
|
goto descend_into_child_node;
|
| 435 |
|
|
}
|
| 436 |
|
|
ntfs_error(sb, "Negative child node vcn in inode 0x%lx.",
|
| 437 |
|
|
idx_ni->mft_no);
|
| 438 |
|
|
unm_err_out:
|
| 439 |
|
|
unlock_page(page);
|
| 440 |
|
|
ntfs_unmap_page(page);
|
| 441 |
|
|
err_out:
|
| 442 |
|
|
if (!err)
|
| 443 |
|
|
err = -EIO;
|
| 444 |
|
|
if (actx)
|
| 445 |
|
|
ntfs_attr_put_search_ctx(actx);
|
| 446 |
|
|
if (m)
|
| 447 |
|
|
unmap_mft_record(base_ni);
|
| 448 |
|
|
return err;
|
| 449 |
|
|
idx_err_out:
|
| 450 |
|
|
ntfs_error(sb, "Corrupt index. Aborting lookup.");
|
| 451 |
|
|
goto err_out;
|
| 452 |
|
|
}
|
