4 * Copyright (C) 1995, 1996 Paul H. Hargrove
5 * This file may be distributed under the terms of the GNU Public License.
7 * This file contains the file-related functions which are independent of
8 * which scheme is being used to represent forks.
10 * Based on the minix file system code, (C) 1991, 1992 by Linus Torvalds
12 * "XXX" in a comment is a note to myself to consider changing something.
14 * In function preconditions the term "valid" applied to a pointer to
15 * a structure means that the pointer is non-NULL and the structure it
16 * points to has all fields initialized to consistent values.
20 #include <linux/hfs_fs_sb.h>
21 #include <linux/hfs_fs_i.h>
22 #include <linux/hfs_fs.h>
24 /*================ Forward declarations ================*/
26 static hfs_rwret_t
hfs_file_read(struct file
*, char *, hfs_rwarg_t
,
28 static hfs_rwret_t
hfs_file_write(struct file
*, const char *, hfs_rwarg_t
,
30 static void hfs_file_truncate(struct inode
*);
32 /*================ Global variables ================*/
34 struct file_operations hfs_file_operations
= {
36 write
: hfs_file_write
,
37 mmap
: generic_file_mmap
,
41 struct inode_operations hfs_file_inode_operations
= {
42 truncate
: hfs_file_truncate
,
43 setattr
: hfs_notify_change
,
46 /*================ Variable-like macros ================*/
48 /* maximum number of blocks to try to read in at once */
51 /*================ File-local functions ================*/
56 * Given an hfs_fork and a block number return the buffer_head for
57 * that block from the fork. If 'create' is non-zero then allocate
58 * the necessary block(s) to the fork.
60 struct buffer_head
*hfs_getblk(struct hfs_fork
*fork
, int block
, int create
)
63 kdev_t dev
= fork
->entry
->mdb
->sys_mdb
->s_dev
;
65 tmp
= hfs_extent_map(fork
, block
, create
);
68 /* If writing the block, then we have exclusive access
69 to the file until we return, so it can't have moved.
72 hfs_cat_mark_dirty(fork
->entry
);
73 return getblk(dev
, tmp
, HFS_SECTOR_SIZE
);
77 /* If reading the block, then retry since the
78 location on disk could have changed while
79 we waited on the I/O in getblk to complete.
82 struct buffer_head
*bh
=
83 getblk(dev
, tmp
, HFS_SECTOR_SIZE
);
84 int tmp2
= hfs_extent_map(fork
, block
, 0);
89 /* The block moved or no longer exists. */
95 /* The block no longer exists. */
103 * This is the hfs_get_block() field in the inode_operations structure for
104 * "regular" (non-header) files. The purpose is to translate an inode
105 * and a block number within the corresponding file into a physical
106 * block number. This function just calls hfs_extent_map() to do the
107 * real work and then stuffs the appropriate info into the buffer_head.
109 int hfs_get_block(struct inode
*inode
, long iblock
, struct buffer_head
*bh_result
, int create
)
113 phys
= hfs_extent_map(HFS_I(inode
)->fork
, iblock
, create
);
115 bh_result
->b_dev
= inode
->i_dev
;
116 bh_result
->b_blocknr
= phys
;
117 bh_result
->b_state
|= (1UL << BH_Mapped
);
119 bh_result
->b_state
|= (1UL << BH_New
);
126 /* we tried to add stuff, but we couldn't. send back an out-of-space
135 * This is the read field in the inode_operations structure for
136 * "regular" (non-header) files. The purpose is to transfer up to
137 * 'count' bytes from the file corresponding to 'inode', beginning at
138 * 'filp->offset' bytes into the file. The data is transfered to
139 * user-space at the address 'buf'. Returns the number of bytes
140 * successfully transfered. This function checks the arguments, does
141 * some setup and then calls hfs_do_read() to do the actual transfer. */
142 static hfs_rwret_t
hfs_file_read(struct file
* filp
, char * buf
,
143 hfs_rwarg_t count
, loff_t
*ppos
)
145 struct inode
*inode
= filp
->f_dentry
->d_inode
;
146 hfs_s32 read
, left
, pos
, size
;
148 if (!S_ISREG(inode
->i_mode
)) {
149 hfs_warn("hfs_file_read: mode = %07o\n",inode
->i_mode
);
153 if (pos
>= HFS_FORK_MAX
) {
156 size
= inode
->i_size
;
168 if ((read
= hfs_do_read(inode
, HFS_I(inode
)->fork
, pos
,
169 buf
, left
, filp
->f_reada
!= 0)) > 0) {
180 * This is the write() entry in the file_operations structure for
181 * "regular" files. The purpose is to transfer up to 'count' bytes
182 * to the file corresponding to 'inode' beginning at offset
183 * 'file->f_pos' from user-space at the address 'buf'. The return
184 * value is the number of bytes actually transferred.
186 static hfs_rwret_t
hfs_file_write(struct file
* filp
, const char * buf
,
187 hfs_rwarg_t count
, loff_t
*ppos
)
189 struct inode
*inode
= filp
->f_dentry
->d_inode
;
190 struct hfs_fork
*fork
= HFS_I(inode
)->fork
;
191 hfs_s32 written
, pos
;
193 if (!S_ISREG(inode
->i_mode
)) {
194 hfs_warn("hfs_file_write: mode = %07o\n", inode
->i_mode
);
198 pos
= (filp
->f_flags
& O_APPEND
) ? inode
->i_size
: *ppos
;
200 if (pos
>= HFS_FORK_MAX
) {
203 if (count
> HFS_FORK_MAX
) {
204 count
= HFS_FORK_MAX
;
206 if ((written
= hfs_do_write(inode
, fork
, pos
, buf
, count
)) > 0)
210 if (*ppos
> inode
->i_size
) {
211 inode
->i_size
= *ppos
;
212 mark_inode_dirty(inode
);
219 * hfs_file_truncate()
221 * This is the truncate() entry in the file_operations structure for
222 * "regular" files. The purpose is to change the length of the file
223 * corresponding to the given inode. Changes can either lengthen or
226 static void hfs_file_truncate(struct inode
* inode
)
228 struct hfs_fork
*fork
= HFS_I(inode
)->fork
;
230 fork
->lsize
= inode
->i_size
;
231 hfs_extent_adj(fork
);
232 hfs_cat_mark_dirty(HFS_I(inode
)->entry
);
234 inode
->i_size
= fork
->lsize
;
235 inode
->i_blocks
= fork
->psize
;
236 mark_inode_dirty(inode
);
242 * Like copy_to_user() while translating CR->NL.
244 static inline void xlate_to_user(char *buf
, const char *data
, int count
)
250 put_user((ch
== '\r') ? '\n' : ch
, buf
++);
257 * Like copy_from_user() while translating NL->CR;
259 static inline int xlate_from_user(char *data
, const char *buf
, int count
)
263 i
= copy_from_user(data
, buf
, count
);
274 /*================ Global functions ================*/
279 * This function transfers actual data from disk to user-space memory,
280 * returning the number of bytes successfully transfered. 'fork' tells
281 * which file on the disk to read from. 'pos' gives the offset into
282 * the Linux file at which to begin the transfer. Note that this will
283 * differ from 'filp->offset' in the case of an AppleDouble header file
284 * due to the block of metadata at the beginning of the file, which has
285 * no corresponding place in the HFS file. 'count' tells how many
286 * bytes to transfer. 'buf' gives an address in user-space to transfer
289 * This is based on Linus's minix_file_read().
290 * It has been changed to take into account that HFS files have no holes.
292 hfs_s32
hfs_do_read(struct inode
*inode
, struct hfs_fork
* fork
, hfs_u32 pos
,
293 char * buf
, hfs_u32 count
, int reada
)
295 kdev_t dev
= inode
->i_dev
;
296 hfs_s32 size
, chars
, offset
, block
, blocks
, read
= 0;
297 int bhrequest
, uptodate
;
298 int convert
= HFS_I(inode
)->convert
;
299 struct buffer_head
** bhb
, ** bhe
;
300 struct buffer_head
* bhreq
[NBUF
];
301 struct buffer_head
* buflist
[NBUF
];
303 /* split 'pos' in to block and (byte) offset components */
304 block
= pos
>> HFS_SECTOR_SIZE_BITS
;
305 offset
= pos
& (HFS_SECTOR_SIZE
-1);
307 /* compute the logical size of the fork in blocks */
308 size
= (fork
->lsize
+ (HFS_SECTOR_SIZE
-1)) >> HFS_SECTOR_SIZE_BITS
;
310 /* compute the number of physical blocks to be transferred */
311 blocks
= (count
+offset
+HFS_SECTOR_SIZE
-1) >> HFS_SECTOR_SIZE_BITS
;
315 if (blocks
< read_ahead
[MAJOR(dev
)] / (HFS_SECTOR_SIZE
>>9)) {
316 blocks
= read_ahead
[MAJOR(dev
)] / (HFS_SECTOR_SIZE
>>9);
318 if (block
+ blocks
> size
) {
319 blocks
= size
- block
;
323 /* We do this in a two stage process. We first try and
324 request as many blocks as we can, then we wait for the
325 first one to complete, and then we try and wrap up as many
326 as are actually done.
328 This routine is optimized to make maximum use of the
329 various buffers and caches. */
336 *bhb
= hfs_getblk(fork
, block
++, 0);
339 /* Since there are no holes in HFS files
340 we must have encountered an error.
341 So, stop adding blocks to the queue. */
346 if (!buffer_uptodate(*bhb
)) {
348 bhreq
[bhrequest
++] = *bhb
;
351 if (++bhb
== &buflist
[NBUF
]) {
355 /* If the block we have on hand is uptodate,
356 go ahead and complete processing. */
365 /* If the only block in the queue is bad then quit */
370 /* Now request them all */
372 ll_rw_block(READ
, bhrequest
, bhreq
);
375 do { /* Finish off all I/O that has actually completed */
378 wait_on_buffer(*bhe
);
380 if (!buffer_uptodate(*bhe
)) {
383 if (++bhe
== &buflist
[NBUF
]) {
390 if (count
< HFS_SECTOR_SIZE
- offset
) {
393 chars
= HFS_SECTOR_SIZE
- offset
;
395 p
= (*bhe
)->b_data
+ offset
;
397 xlate_to_user(buf
, p
, chars
);
399 chars
-= copy_to_user(buf
, p
, chars
);
413 if (++bhe
== &buflist
[NBUF
]) {
416 } while (count
&& (bhe
!= bhb
) && !buffer_locked(*bhe
));
419 /* Release the read-ahead blocks */
422 if (++bhe
== &buflist
[NBUF
]) {
435 * This function transfers actual data from user-space memory to disk,
436 * returning the number of bytes successfully transfered. 'fork' tells
437 * which file on the disk to write to. 'pos' gives the offset into
438 * the Linux file at which to begin the transfer. Note that this will
439 * differ from 'filp->offset' in the case of an AppleDouble header file
440 * due to the block of metadata at the beginning of the file, which has
441 * no corresponding place in the HFS file. 'count' tells how many
442 * bytes to transfer. 'buf' gives an address in user-space to transfer
445 * This is just a minor edit of Linus's minix_file_write().
447 hfs_s32
hfs_do_write(struct inode
*inode
, struct hfs_fork
* fork
, hfs_u32 pos
,
448 const char * buf
, hfs_u32 count
)
451 struct buffer_head
* bh
;
453 int convert
= HFS_I(inode
)->convert
;
456 while (written
< count
) {
457 bh
= hfs_getblk(fork
, pos
/HFS_SECTOR_SIZE
, 1);
464 c
= HFS_SECTOR_SIZE
- (pos
% HFS_SECTOR_SIZE
);
465 if (c
> count
- written
) {
468 if (c
!= HFS_SECTOR_SIZE
&& !buffer_uptodate(bh
)) {
469 ll_rw_block(READ
, 1, &bh
);
471 if (!buffer_uptodate(bh
)) {
479 p
= (pos
% HFS_SECTOR_SIZE
) + bh
->b_data
;
480 c
-= convert
? xlate_from_user(p
, buf
, c
) :
481 copy_from_user(p
, buf
, c
);
491 mark_buffer_uptodate(bh
, 1);
492 mark_buffer_dirty(bh
);
496 struct hfs_cat_entry
*entry
= fork
->entry
;
498 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME
;
499 if (pos
> fork
->lsize
) {
502 entry
->modify_date
= hfs_u_to_mtime(CURRENT_TIME
);
503 hfs_cat_mark_dirty(entry
);
509 * hfs_file_fix_mode()
511 * Fixes up the permissions on a file after changing the write-inhibit bit.
513 void hfs_file_fix_mode(struct hfs_cat_entry
*entry
)
515 struct dentry
**de
= entry
->sys_entry
;
518 if (entry
->u
.file
.flags
& HFS_FIL_LOCK
) {
519 for (i
= 0; i
< 4; ++i
) {
521 de
[i
]->d_inode
->i_mode
&= ~S_IWUGO
;
525 for (i
= 0; i
< 4; ++i
) {
527 struct inode
*inode
= de
[i
]->d_inode
;
528 inode
->i_mode
|= S_IWUGO
;
530 ~HFS_SB(inode
->i_sb
)->s_umask
;