/* * 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); } /** * 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 */