fs/ntfs/ntfs.h

   1 /*
   2  * ntfs.h - Defines for NTFS Linux kernel driver. Part of the Linux-NTFS
   3  *          project.
   4  *
   5  * Copyright (c) 2001-2004 Anton Altaparmakov
   6  * Copyright (C) 2002 Richard Russon
   7  *
   8  * This program/include file is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as published
  10  * by the Free Software Foundation; either version 2 of the License, or
  11  * (at your option) any later version.
  12  *
  13  * This program/include file is distributed in the hope that it will be
  14  * useful, but WITHOUT ANY WARRANTY; without even the implied warranty
  15  * of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program (in the main directory of the Linux-NTFS
  20  * distribution in the file COPYING); if not, write to the Free Software
  21  * Foundation,Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  22  */
  23
  24 #ifndef _LINUX_NTFS_H
  25 #define _LINUX_NTFS_H
  26
  27 #include <linux/stddef.h>
  28 #include <linux/kernel.h>
  29 #include <linux/module.h>
  30 #include <linux/compiler.h>
  31 #include <linux/fs.h>
  32 #include <linux/buffer_head.h>
  33 #include <linux/nls.h>
  34 #include <linux/pagemap.h>
  35 #include <linux/smp.h>
  36 #include <asm/atomic.h>
  37
  38 #include "types.h"
  39 #include "debug.h"
  40 #include "malloc.h"
  41 #include "endian.h"
  42 #include "volume.h"
  43 #include "inode.h"
  44 #include "layout.h"
  45 #include "attrib.h"
  46 #include "mft.h"
  47
  48 typedef enum {
  49         NTFS_BLOCK_SIZE         = 512,
  50         NTFS_BLOCK_SIZE_BITS    = 9,
  51         NTFS_SB_MAGIC           = 0x5346544e,   /* 'NTFS' */
  52         NTFS_MAX_NAME_LEN       = 255,
  53 } NTFS_CONSTANTS;
  54
  55 /* Global variables. */
  56
  57 /* Slab caches (from super.c). */
  58 extern kmem_cache_t *ntfs_name_cache;
  59 extern kmem_cache_t *ntfs_inode_cache;
  60 extern kmem_cache_t *ntfs_big_inode_cache;
  61 extern kmem_cache_t *ntfs_attr_ctx_cache;
  62 extern kmem_cache_t *ntfs_index_ctx_cache;
  63
  64 /* The various operations structs defined throughout the driver files. */
  65 extern struct super_operations ntfs_sops;
  66 extern struct address_space_operations ntfs_aops;
  67 extern struct address_space_operations ntfs_mst_aops;
  68 extern struct address_space_operations ntfs_mft_aops;
  69
  70 extern struct  file_operations ntfs_file_ops;
  71 extern struct inode_operations ntfs_file_inode_ops;
  72
  73 extern struct  file_operations ntfs_dir_ops;
  74 extern struct inode_operations ntfs_dir_inode_ops;
  75
  76 extern struct  file_operations ntfs_empty_file_ops;
  77 extern struct inode_operations ntfs_empty_inode_ops;
  78
  79 /**
  80  * NTFS_SB - return the ntfs volume given a vfs super block
  81  * @sb:         VFS super block
  82  *
  83  * NTFS_SB() returns the ntfs volume associated with the VFS super block @sb.
  84  */
  85 static inline ntfs_volume *NTFS_SB(struct super_block *sb)
  86 {
  87         return sb->s_fs_info;
  88 }
  89
  90 /**
  91  * ntfs_unmap_page - release a page that was mapped using ntfs_map_page()
  92  * @page:       the page to release
  93  *
  94  * Unpin, unmap and release a page that was obtained from ntfs_map_page().
  95  */
  96 static inline void ntfs_unmap_page(struct page *page)
  97 {
  98         kunmap(page);
  99         page_cache_release(page);
 100 }
 101
 102 /**
 103  * ntfs_map_page - map a page into accessible memory, reading it if necessary
 104  * @mapping:    address space for which to obtain the page
 105  * @index:      index into the page cache for @mapping of the page to map
 106  *
 107  * Read a page from the page cache of the address space @mapping at position
 108  * @index, where @index is in units of PAGE_CACHE_SIZE, and not in bytes.
 109  *
 110  * If the page is not in memory it is loaded from disk first using the readpage
 111  * method defined in the address space operations of @mapping and the page is
 112  * added to the page cache of @mapping in the process.
 113  *
 114  * If the page is in high memory it is mapped into memory directly addressible
 115  * by the kernel.
 116  *
 117  * Finally the page count is incremented, thus pinning the page into place.
 118  *
 119  * The above means that page_address(page) can be used on all pages obtained
 120  * with ntfs_map_page() to get the kernel virtual address of the page.
 121  *
 122  * When finished with the page, the caller has to call ntfs_unmap_page() to
 123  * unpin, unmap and release the page.
 124  *
 125  * Note this does not grant exclusive access. If such is desired, the caller
 126  * must provide it independently of the ntfs_{un}map_page() calls by using
 127  * a {rw_}semaphore or other means of serialization. A spin lock cannot be
 128  * used as ntfs_map_page() can block.
 129  *
 130  * The unlocked and uptodate page is returned on success or an encoded error
 131  * on failure. Caller has to test for error using the IS_ERR() macro on the
 132  * return value. If that evaluates to TRUE, the negative error code can be
 133  * obtained using PTR_ERR() on the return value of ntfs_map_page().
 134  */
 135 static inline struct page *ntfs_map_page(struct address_space *mapping,
 136                 unsigned long index)
 137 {
 138         struct page *page = read_cache_page(mapping, index,
 139                         (filler_t*)mapping->a_ops->readpage, NULL);
 140
 141         if (!IS_ERR(page)) {
 142                 wait_on_page_locked(page);
 143                 kmap(page);
 144                 if (PageUptodate(page) && !PageError(page))
 145                         return page;
 146                 ntfs_unmap_page(page);
 147                 return ERR_PTR(-EIO);
 148         }
 149         return page;
 150 }
 151
 152 /* Declarations of functions and global variables. */
 153
 154 /* From fs/ntfs/compress.c */
 155 extern int ntfs_read_compressed_block(struct page *page);
 156
 157 /* From fs/ntfs/super.c */
 158 #define default_upcase_len 0x10000
 159 extern ntfschar *default_upcase;
 160 extern unsigned long ntfs_nr_upcase_users;
 161 extern struct semaphore ntfs_lock;
 162
 163 typedef struct {
 164         int val;
 165         char *str;
 166 } option_t;
 167 extern const option_t on_errors_arr[];
 168
 169 /* From fs/ntfs/compress.c */
 170 extern int allocate_compression_buffers(void);
 171 extern void free_compression_buffers(void);
 172
 173 /* From fs/ntfs/mst.c */
 174 extern int post_read_mst_fixup(NTFS_RECORD *b, const u32 size);
 175 extern int pre_write_mst_fixup(NTFS_RECORD *b, const u32 size);
 176 extern void post_write_mst_fixup(NTFS_RECORD *b);
 177
 178 /* From fs/ntfs/unistr.c */
 179 extern BOOL ntfs_are_names_equal(const ntfschar *s1, size_t s1_len,
 180                 const ntfschar *s2, size_t s2_len,
 181                 const IGNORE_CASE_BOOL ic,
 182                 const ntfschar *upcase, const u32 upcase_size);
 183 extern int ntfs_collate_names(const ntfschar *name1, const u32 name1_len,
 184                 const ntfschar *name2, const u32 name2_len,
 185                 const int err_val, const IGNORE_CASE_BOOL ic,
 186                 const ntfschar *upcase, const u32 upcase_len);
 187 extern int ntfs_ucsncmp(const ntfschar *s1, const ntfschar *s2, size_t n);
 188 extern int ntfs_ucsncasecmp(const ntfschar *s1, const ntfschar *s2, size_t n,
 189                 const ntfschar *upcase, const u32 upcase_size);
 190 extern void ntfs_upcase_name(ntfschar *name, u32 name_len,
 191                 const ntfschar *upcase, const u32 upcase_len);
 192 extern void ntfs_file_upcase_value(FILE_NAME_ATTR *file_name_attr,
 193                 const ntfschar *upcase, const u32 upcase_len);
 194 extern int ntfs_file_compare_values(FILE_NAME_ATTR *file_name_attr1,
 195                 FILE_NAME_ATTR *file_name_attr2,
 196                 const int err_val, const IGNORE_CASE_BOOL ic,
 197                 const ntfschar *upcase, const u32 upcase_len);
 198 extern int ntfs_nlstoucs(const ntfs_volume *vol, const char *ins,
 199                 const int ins_len, ntfschar **outs);
 200 extern int ntfs_ucstonls(const ntfs_volume *vol, const ntfschar *ins,
 201                 const int ins_len, unsigned char **outs, int outs_len);
 202
 203 /* From fs/ntfs/upcase.c */
 204 extern ntfschar *generate_default_upcase(void);
 205
 206 #endif /* _LINUX_NTFS_H */