cregit-Linux how code gets into the kernel

Release 4.10 fs/ntfs/index.h

Directory: fs/ntfs
/*
 * index.h - Defines for NTFS kernel index handling.  Part of the Linux-NTFS
 *           project.
 *
 * Copyright (c) 2004 Anton Altaparmakov
 *
 * This program/include file is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program/include file is distributed in the hope that it will be
 * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
 * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program (in the main directory of the Linux-NTFS
 * distribution in the file COPYING); if not, write to the Free Software
 * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#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); }

Contributors

PersonTokensPropCommitsCommitProp
anton altaparmakovanton altaparmakov34100.00%1100.00%
Total34100.00%1100.00%

/** * 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)); }

Contributors

PersonTokensPropCommitsCommitProp
anton altaparmakovanton altaparmakov53100.00%2100.00%
Total53100.00%2100.00%

#endif /* NTFS_RW */ #endif /* _LINUX_NTFS_INDEX_H */

Overall Contributors

PersonTokensPropCommitsCommitProp
anton altaparmakovanton altaparmakov20799.04%480.00%
richard knutssonrichard knutsson20.96%120.00%
Total209100.00%5100.00%
Directory: fs/ntfs
Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.