2 * linux/fs/ufs/truncate.c
5 * Daniel Pirkl <daniel.pirkl@email.cz>
6 * Charles University, Faculty of Mathematics and Physics
10 * linux/fs/ext2/truncate.c
12 * Copyright (C) 1992, 1993, 1994, 1995
13 * Remy Card (card@masi.ibp.fr)
14 * Laboratoire MASI - Institut Blaise Pascal
15 * Universite Pierre et Marie Curie (Paris VI)
19 * linux/fs/minix/truncate.c
21 * Copyright (C) 1991, 1992 Linus Torvalds
23 * Big-endian to little-endian byte-swapping/bitmaps by
24 * David S. Miller (davem@caip.rutgers.edu), 1995
28 * Real random numbers for secure rm added 94/02/18
29 * Idea from Pierre del Perugia <delperug@gla.ecoledoc.ibp.fr>
32 #include <linux/errno.h>
34 #include <linux/ufs_fs.h>
35 #include <linux/fcntl.h>
36 #include <linux/time.h>
37 #include <linux/stat.h>
38 #include <linux/string.h>
39 #include <linux/smp_lock.h>
40 #include <linux/buffer_head.h>
41 #include <linux/blkdev.h>
42 #include <linux/sched.h>
47 #undef UFS_TRUNCATE_DEBUG
49 #ifdef UFS_TRUNCATE_DEBUG
50 #define UFSD(x) printk("(%s, %d), %s: ", __FILE__, __LINE__, __FUNCTION__); printk x;
56 * Secure deletion currently doesn't work. It interacts very badly
57 * with buffers shared with memory mappings, and for that reason
58 * can't be done in the truncate() routines. It should instead be
59 * done separately in "release()" before calling the truncate routines
60 * that will release the actual file blocks.
65 #define DIRECT_BLOCK ((inode->i_size + uspi->s_bsize - 1) >> uspi->s_bshift)
66 #define DIRECT_FRAGMENT ((inode->i_size + uspi->s_fsize - 1) >> uspi->s_fshift)
68 #define DATA_BUFFER_USED(bh) \
69 (atomic_read(&bh->b_count)>1 || buffer_locked(bh))
71 static int ufs_trunc_direct (struct inode
* inode
)
73 struct ufs_inode_info
*ufsi
= UFS_I(inode
);
74 struct super_block
* sb
;
75 struct ufs_sb_private_info
* uspi
;
76 struct buffer_head
* bh
;
78 unsigned frag1
, frag2
, frag3
, frag4
, block1
, block2
;
79 unsigned frag_to_free
, free_count
;
86 uspi
= UFS_SB(sb
)->s_uspi
;
92 frag1
= DIRECT_FRAGMENT
;
93 frag4
= min_t(u32
, UFS_NDIR_FRAGMENT
, ufsi
->i_lastfrag
);
94 frag2
= ((frag1
& uspi
->s_fpbmask
) ? ((frag1
| uspi
->s_fpbmask
) + 1) : frag1
);
95 frag3
= frag4
& ~uspi
->s_fpbmask
;
101 else if (frag2
< frag3
) {
102 block1
= ufs_fragstoblks (frag2
);
103 block2
= ufs_fragstoblks (frag3
);
106 UFSD(("frag1 %u, frag2 %u, block1 %u, block2 %u, frag3 %u, frag4 %u\n", frag1
, frag2
, block1
, block2
, frag3
, frag4
))
112 * Free first free fragments
114 p
= ufsi
->i_u1
.i_data
+ ufs_fragstoblks (frag1
);
115 tmp
= fs32_to_cpu(sb
, *p
);
117 ufs_panic (sb
, "ufs_trunc_direct", "internal error");
118 frag1
= ufs_fragnum (frag1
);
119 frag2
= ufs_fragnum (frag2
);
120 for (j
= frag1
; j
< frag2
; j
++) {
121 bh
= sb_find_get_block (sb
, tmp
+ j
);
122 if ((bh
&& DATA_BUFFER_USED(bh
)) || tmp
!= fs32_to_cpu(sb
, *p
)) {
129 inode
->i_blocks
-= (frag2
-frag1
) << uspi
->s_nspfshift
;
130 mark_inode_dirty(inode
);
131 ufs_free_fragments (inode
, tmp
+ frag1
, frag2
- frag1
);
132 frag_to_free
= tmp
+ frag1
;
138 for (i
= block1
; i
< block2
; i
++) {
139 p
= ufsi
->i_u1
.i_data
+ i
;
140 tmp
= fs32_to_cpu(sb
, *p
);
143 for (j
= 0; j
< uspi
->s_fpb
; j
++) {
144 bh
= sb_find_get_block(sb
, tmp
+ j
);
145 if ((bh
&& DATA_BUFFER_USED(bh
)) || tmp
!= fs32_to_cpu(sb
, *p
)) {
153 inode
->i_blocks
-= uspi
->s_nspb
;
154 mark_inode_dirty(inode
);
155 if (free_count
== 0) {
157 free_count
= uspi
->s_fpb
;
158 } else if (free_count
> 0 && frag_to_free
== tmp
- free_count
)
159 free_count
+= uspi
->s_fpb
;
161 ufs_free_blocks (inode
, frag_to_free
, free_count
);
163 free_count
= uspi
->s_fpb
;
169 ufs_free_blocks (inode
, frag_to_free
, free_count
);
175 * Free last free fragments
177 p
= ufsi
->i_u1
.i_data
+ ufs_fragstoblks (frag3
);
178 tmp
= fs32_to_cpu(sb
, *p
);
180 ufs_panic(sb
, "ufs_truncate_direct", "internal error");
181 frag4
= ufs_fragnum (frag4
);
182 for (j
= 0; j
< frag4
; j
++) {
183 bh
= sb_find_get_block (sb
, tmp
+ j
);
184 if ((bh
&& DATA_BUFFER_USED(bh
)) || tmp
!= fs32_to_cpu(sb
, *p
)) {
192 inode
->i_blocks
-= frag4
<< uspi
->s_nspfshift
;
193 mark_inode_dirty(inode
);
194 ufs_free_fragments (inode
, tmp
, frag4
);
202 static int ufs_trunc_indirect (struct inode
* inode
, unsigned offset
, __fs32
*p
)
204 struct super_block
* sb
;
205 struct ufs_sb_private_info
* uspi
;
206 struct ufs_buffer_head
* ind_ubh
;
207 struct buffer_head
* bh
;
209 unsigned indirect_block
, i
, j
, tmp
;
210 unsigned frag_to_free
, free_count
;
216 uspi
= UFS_SB(sb
)->s_uspi
;
222 tmp
= fs32_to_cpu(sb
, *p
);
225 ind_ubh
= ubh_bread(sb
, tmp
, uspi
->s_bsize
);
226 if (tmp
!= fs32_to_cpu(sb
, *p
)) {
227 ubh_brelse (ind_ubh
);
235 indirect_block
= (DIRECT_BLOCK
> offset
) ? (DIRECT_BLOCK
- offset
) : 0;
236 for (i
= indirect_block
; i
< uspi
->s_apb
; i
++) {
237 ind
= ubh_get_addr32 (ind_ubh
, i
);
238 tmp
= fs32_to_cpu(sb
, *ind
);
241 for (j
= 0; j
< uspi
->s_fpb
; j
++) {
242 bh
= sb_find_get_block(sb
, tmp
+ j
);
243 if ((bh
&& DATA_BUFFER_USED(bh
)) || tmp
!= fs32_to_cpu(sb
, *ind
)) {
251 ubh_mark_buffer_dirty(ind_ubh
);
252 if (free_count
== 0) {
254 free_count
= uspi
->s_fpb
;
255 } else if (free_count
> 0 && frag_to_free
== tmp
- free_count
)
256 free_count
+= uspi
->s_fpb
;
258 ufs_free_blocks (inode
, frag_to_free
, free_count
);
260 free_count
= uspi
->s_fpb
;
262 inode
->i_blocks
-= uspi
->s_nspb
;
263 mark_inode_dirty(inode
);
267 if (free_count
> 0) {
268 ufs_free_blocks (inode
, frag_to_free
, free_count
);
270 for (i
= 0; i
< uspi
->s_apb
; i
++)
271 if (*ubh_get_addr32(ind_ubh
,i
))
273 if (i
>= uspi
->s_apb
) {
274 if (ubh_max_bcount(ind_ubh
) != 1) {
278 tmp
= fs32_to_cpu(sb
, *p
);
280 inode
->i_blocks
-= uspi
->s_nspb
;
281 mark_inode_dirty(inode
);
282 ufs_free_blocks (inode
, tmp
, uspi
->s_fpb
);
283 ubh_bforget(ind_ubh
);
287 if (IS_SYNC(inode
) && ind_ubh
&& ubh_buffer_dirty(ind_ubh
)) {
288 ubh_wait_on_buffer (ind_ubh
);
289 ubh_ll_rw_block (WRITE
, 1, &ind_ubh
);
290 ubh_wait_on_buffer (ind_ubh
);
292 ubh_brelse (ind_ubh
);
299 static int ufs_trunc_dindirect (struct inode
*inode
, unsigned offset
, __fs32
*p
)
301 struct super_block
* sb
;
302 struct ufs_sb_private_info
* uspi
;
303 struct ufs_buffer_head
* dind_bh
;
304 unsigned i
, tmp
, dindirect_block
;
311 uspi
= UFS_SB(sb
)->s_uspi
;
313 dindirect_block
= (DIRECT_BLOCK
> offset
)
314 ? ((DIRECT_BLOCK
- offset
) >> uspi
->s_apbshift
) : 0;
317 tmp
= fs32_to_cpu(sb
, *p
);
320 dind_bh
= ubh_bread(sb
, tmp
, uspi
->s_bsize
);
321 if (tmp
!= fs32_to_cpu(sb
, *p
)) {
322 ubh_brelse (dind_bh
);
330 for (i
= dindirect_block
; i
< uspi
->s_apb
; i
++) {
331 dind
= ubh_get_addr32 (dind_bh
, i
);
332 tmp
= fs32_to_cpu(sb
, *dind
);
335 retry
|= ufs_trunc_indirect (inode
, offset
+ (i
<< uspi
->s_apbshift
), dind
);
336 ubh_mark_buffer_dirty(dind_bh
);
339 for (i
= 0; i
< uspi
->s_apb
; i
++)
340 if (*ubh_get_addr32 (dind_bh
, i
))
342 if (i
>= uspi
->s_apb
) {
343 if (ubh_max_bcount(dind_bh
) != 1)
346 tmp
= fs32_to_cpu(sb
, *p
);
348 inode
->i_blocks
-= uspi
->s_nspb
;
349 mark_inode_dirty(inode
);
350 ufs_free_blocks (inode
, tmp
, uspi
->s_fpb
);
351 ubh_bforget(dind_bh
);
355 if (IS_SYNC(inode
) && dind_bh
&& ubh_buffer_dirty(dind_bh
)) {
356 ubh_wait_on_buffer (dind_bh
);
357 ubh_ll_rw_block (WRITE
, 1, &dind_bh
);
358 ubh_wait_on_buffer (dind_bh
);
360 ubh_brelse (dind_bh
);
367 static int ufs_trunc_tindirect (struct inode
* inode
)
369 struct ufs_inode_info
*ufsi
= UFS_I(inode
);
370 struct super_block
* sb
;
371 struct ufs_sb_private_info
* uspi
;
372 struct ufs_buffer_head
* tind_bh
;
373 unsigned tindirect_block
, tmp
, i
;
380 uspi
= UFS_SB(sb
)->s_uspi
;
383 tindirect_block
= (DIRECT_BLOCK
> (UFS_NDADDR
+ uspi
->s_apb
+ uspi
->s_2apb
))
384 ? ((DIRECT_BLOCK
- UFS_NDADDR
- uspi
->s_apb
- uspi
->s_2apb
) >> uspi
->s_2apbshift
) : 0;
385 p
= ufsi
->i_u1
.i_data
+ UFS_TIND_BLOCK
;
386 if (!(tmp
= fs32_to_cpu(sb
, *p
)))
388 tind_bh
= ubh_bread (sb
, tmp
, uspi
->s_bsize
);
389 if (tmp
!= fs32_to_cpu(sb
, *p
)) {
390 ubh_brelse (tind_bh
);
398 for (i
= tindirect_block
; i
< uspi
->s_apb
; i
++) {
399 tind
= ubh_get_addr32 (tind_bh
, i
);
400 retry
|= ufs_trunc_dindirect(inode
, UFS_NDADDR
+
401 uspi
->s_apb
+ ((i
+ 1) << uspi
->s_2apbshift
), tind
);
402 ubh_mark_buffer_dirty(tind_bh
);
404 for (i
= 0; i
< uspi
->s_apb
; i
++)
405 if (*ubh_get_addr32 (tind_bh
, i
))
407 if (i
>= uspi
->s_apb
) {
408 if (ubh_max_bcount(tind_bh
) != 1)
411 tmp
= fs32_to_cpu(sb
, *p
);
413 inode
->i_blocks
-= uspi
->s_nspb
;
414 mark_inode_dirty(inode
);
415 ufs_free_blocks (inode
, tmp
, uspi
->s_fpb
);
416 ubh_bforget(tind_bh
);
420 if (IS_SYNC(inode
) && tind_bh
&& ubh_buffer_dirty(tind_bh
)) {
421 ubh_wait_on_buffer (tind_bh
);
422 ubh_ll_rw_block (WRITE
, 1, &tind_bh
);
423 ubh_wait_on_buffer (tind_bh
);
425 ubh_brelse (tind_bh
);
431 void ufs_truncate (struct inode
* inode
)
433 struct ufs_inode_info
*ufsi
= UFS_I(inode
);
434 struct super_block
* sb
;
435 struct ufs_sb_private_info
* uspi
;
436 struct buffer_head
* bh
;
442 uspi
= UFS_SB(sb
)->s_uspi
;
444 if (!(S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
) || S_ISLNK(inode
->i_mode
)))
446 if (IS_APPEND(inode
) || IS_IMMUTABLE(inode
))
450 retry
= ufs_trunc_direct(inode
);
451 retry
|= ufs_trunc_indirect (inode
, UFS_IND_BLOCK
,
452 (__fs32
*) &ufsi
->i_u1
.i_data
[UFS_IND_BLOCK
]);
453 retry
|= ufs_trunc_dindirect (inode
, UFS_IND_BLOCK
+ uspi
->s_apb
,
454 (__fs32
*) &ufsi
->i_u1
.i_data
[UFS_DIND_BLOCK
]);
455 retry
|= ufs_trunc_tindirect (inode
);
458 if (IS_SYNC(inode
) && (inode
->i_state
& I_DIRTY
))
459 ufs_sync_inode (inode
);
460 blk_run_address_space(inode
->i_mapping
);
463 offset
= inode
->i_size
& uspi
->s_fshift
;
465 bh
= ufs_bread (inode
, inode
->i_size
>> uspi
->s_fshift
, 0, &err
);
467 memset (bh
->b_data
+ offset
, 0, uspi
->s_fsize
- offset
);
468 mark_buffer_dirty (bh
);
472 inode
->i_mtime
= inode
->i_ctime
= CURRENT_TIME_SEC
;
473 ufsi
->i_lastfrag
= DIRECT_FRAGMENT
;
475 mark_inode_dirty(inode
);