135 строки
4.7 KiB
C
135 строки
4.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0-or-later */
|
|
/*
|
|
* index.h - Defines for NTFS kernel index handling. Part of the Linux-NTFS
|
|
* project.
|
|
*
|
|
* Copyright (c) 2004 Anton Altaparmakov
|
|
*/
|
|
|
|
#ifndef _LINUX_NTFS_INDEX_H
|
|
#define _LINUX_NTFS_INDEX_H
|
|
|
|
#include <linux/fs.h>
|
|
|
|
#include "types.h"
|
|
#include "layout.h"
|
|
#include "inode.h"
|
|
#include "attrib.h"
|
|
#include "mft.h"
|
|
#include "aops.h"
|
|
|
|
/**
|
|
* @idx_ni: index inode containing the @entry described by this context
|
|
* @entry: index entry (points into @ir or @ia)
|
|
* @data: index entry data (points into @entry)
|
|
* @data_len: length in bytes of @data
|
|
* @is_in_root: 'true' if @entry is in @ir and 'false' if it is in @ia
|
|
* @ir: index root if @is_in_root and NULL otherwise
|
|
* @actx: attribute search context if @is_in_root and NULL otherwise
|
|
* @base_ni: base inode if @is_in_root and NULL otherwise
|
|
* @ia: index block if @is_in_root is 'false' and NULL otherwise
|
|
* @page: page if @is_in_root is 'false' and NULL otherwise
|
|
*
|
|
* @idx_ni is the index inode this context belongs to.
|
|
*
|
|
* @entry is the index entry described by this context. @data and @data_len
|
|
* are the index entry data and its length in bytes, respectively. @data
|
|
* simply points into @entry. This is probably what the user is interested in.
|
|
*
|
|
* If @is_in_root is 'true', @entry is in the index root attribute @ir described
|
|
* by the attribute search context @actx and the base inode @base_ni. @ia and
|
|
* @page are NULL in this case.
|
|
*
|
|
* If @is_in_root is 'false', @entry is in the index allocation attribute and @ia
|
|
* and @page point to the index allocation block and the mapped, locked page it
|
|
* is in, respectively. @ir, @actx and @base_ni are NULL in this case.
|
|
*
|
|
* To obtain a context call ntfs_index_ctx_get().
|
|
*
|
|
* We use this context to allow ntfs_index_lookup() to return the found index
|
|
* @entry and its @data without having to allocate a buffer and copy the @entry
|
|
* and/or its @data into it.
|
|
*
|
|
* When finished with the @entry and its @data, call ntfs_index_ctx_put() to
|
|
* free the context and other associated resources.
|
|
*
|
|
* If the index entry was modified, call flush_dcache_index_entry_page()
|
|
* immediately after the modification and either ntfs_index_entry_mark_dirty()
|
|
* or ntfs_index_entry_write() before the call to ntfs_index_ctx_put() to
|
|
* ensure that the changes are written to disk.
|
|
*/
|
|
typedef struct {
|
|
ntfs_inode *idx_ni;
|
|
INDEX_ENTRY *entry;
|
|
void *data;
|
|
u16 data_len;
|
|
bool is_in_root;
|
|
INDEX_ROOT *ir;
|
|
ntfs_attr_search_ctx *actx;
|
|
ntfs_inode *base_ni;
|
|
INDEX_ALLOCATION *ia;
|
|
struct page *page;
|
|
} ntfs_index_context;
|
|
|
|
extern ntfs_index_context *ntfs_index_ctx_get(ntfs_inode *idx_ni);
|
|
extern void ntfs_index_ctx_put(ntfs_index_context *ictx);
|
|
|
|
extern int ntfs_index_lookup(const void *key, const int key_len,
|
|
ntfs_index_context *ictx);
|
|
|
|
#ifdef NTFS_RW
|
|
|
|
/**
|
|
* ntfs_index_entry_flush_dcache_page - flush_dcache_page() for index entries
|
|
* @ictx: ntfs index context describing the index entry
|
|
*
|
|
* Call flush_dcache_page() for the page in which an index entry resides.
|
|
*
|
|
* This must be called every time an index entry is modified, just after the
|
|
* modification.
|
|
*
|
|
* If the index entry is in the index root attribute, simply flush the page
|
|
* containing the mft record containing the index root attribute.
|
|
*
|
|
* If the index entry is in an index block belonging to the index allocation
|
|
* attribute, simply flush the page cache page containing the index block.
|
|
*/
|
|
static inline void ntfs_index_entry_flush_dcache_page(ntfs_index_context *ictx)
|
|
{
|
|
if (ictx->is_in_root)
|
|
flush_dcache_mft_record_page(ictx->actx->ntfs_ino);
|
|
else
|
|
flush_dcache_page(ictx->page);
|
|
}
|
|
|
|
/**
|
|
* ntfs_index_entry_mark_dirty - mark an index entry dirty
|
|
* @ictx: ntfs index context describing the index entry
|
|
*
|
|
* Mark the index entry described by the index entry context @ictx dirty.
|
|
*
|
|
* If the index entry is in the index root attribute, simply mark the mft
|
|
* record containing the index root attribute dirty. This ensures the mft
|
|
* record, and hence the index root attribute, will be written out to disk
|
|
* later.
|
|
*
|
|
* If the index entry is in an index block belonging to the index allocation
|
|
* attribute, mark the buffers belonging to the index record as well as the
|
|
* page cache page the index block is in dirty. This automatically marks the
|
|
* VFS inode of the ntfs index inode to which the index entry belongs dirty,
|
|
* too (I_DIRTY_PAGES) and this in turn ensures the page buffers, and hence the
|
|
* dirty index block, will be written out to disk later.
|
|
*/
|
|
static inline void ntfs_index_entry_mark_dirty(ntfs_index_context *ictx)
|
|
{
|
|
if (ictx->is_in_root)
|
|
mark_mft_record_dirty(ictx->actx->ntfs_ino);
|
|
else
|
|
mark_ntfs_record_dirty(ictx->page,
|
|
(u8*)ictx->ia - (u8*)page_address(ictx->page));
|
|
}
|
|
|
|
#endif /* NTFS_RW */
|
|
|
|
#endif /* _LINUX_NTFS_INDEX_H */
|