1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
|
/*
* truncate.c
*
* PURPOSE
* Truncate handling routines for the OSTA-UDF(tm) filesystem.
*
* COPYRIGHT
* This file is distributed under the terms of the GNU General Public
* License (GPL). Copies of the GPL can be obtained from:
* ftp://prep.ai.mit.edu/pub/gnu/GPL
* Each contributing author retains all rights to their own work.
*
* (C) 1999-2004 Ben Fennema
* (C) 1999 Stelias Computing Inc
*
* HISTORY
*
* 02/24/99 blf Created.
*
*/
#include "udfdecl.h"
#include <linux/fs.h>
#include <linux/mm.h>
#include <linux/udf_fs.h>
#include <linux/buffer_head.h>
#include "udf_i.h"
#include "udf_sb.h"
static void extent_trunc(struct inode * inode, struct extent_position *epos,
kernel_lb_addr eloc, int8_t etype, uint32_t elen, uint32_t nelen)
{
kernel_lb_addr neloc = { 0, 0 };
int last_block = (elen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits;
int first_block = (nelen + inode->i_sb->s_blocksize - 1) >> inode->i_sb->s_blocksize_bits;
if (nelen)
{
if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
{
udf_free_blocks(inode->i_sb, inode, eloc, 0, last_block);
etype = (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30);
}
else
neloc = eloc;
nelen = (etype << 30) | nelen;
}
if (elen != nelen)
{
udf_write_aext(inode, epos, neloc, nelen, 0);
if (last_block - first_block > 0)
{
if (etype == (EXT_RECORDED_ALLOCATED >> 30))
mark_inode_dirty(inode);
if (etype != (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
udf_free_blocks(inode->i_sb, inode, eloc, first_block, last_block - first_block);
}
}
}
void udf_discard_prealloc(struct inode * inode)
{
struct extent_position epos = { NULL, 0, {0, 0}};
kernel_lb_addr eloc;
uint32_t elen, nelen;
uint64_t lbcount = 0;
int8_t etype = -1, netype;
int adsize;
if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_IN_ICB ||
inode->i_size == UDF_I_LENEXTENTS(inode))
return;
if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
adsize = sizeof(short_ad);
else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
adsize = sizeof(long_ad);
else
adsize = 0;
epos.block = UDF_I_LOCATION(inode);
/* Find the last extent in the file */
while ((netype = udf_next_aext(inode, &epos, &eloc, &elen, 1)) != -1)
{
etype = netype;
lbcount += elen;
if (lbcount > inode->i_size && lbcount - inode->i_size < inode->i_sb->s_blocksize)
{
nelen = elen - (lbcount - inode->i_size);
epos.offset -= adsize;
extent_trunc(inode, &epos, eloc, etype, elen, nelen);
epos.offset += adsize;
lbcount = inode->i_size;
}
}
if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30)) {
epos.offset -= adsize;
lbcount -= elen;
extent_trunc(inode, &epos, eloc, etype, elen, 0);
if (!epos.bh)
{
UDF_I_LENALLOC(inode) = epos.offset - udf_file_entry_alloc_offset(inode);
mark_inode_dirty(inode);
}
else
{
struct allocExtDesc *aed = (struct allocExtDesc *)(epos.bh->b_data);
aed->lengthAllocDescs = cpu_to_le32(epos.offset - sizeof(struct allocExtDesc));
if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
udf_update_tag(epos.bh->b_data, epos.offset);
else
udf_update_tag(epos.bh->b_data, sizeof(struct allocExtDesc));
mark_buffer_dirty_inode(epos.bh, inode);
}
}
UDF_I_LENEXTENTS(inode) = lbcount;
brelse(epos.bh);
}
void udf_truncate_extents(struct inode * inode)
{
struct extent_position epos;
kernel_lb_addr eloc, neloc = { 0, 0 };
uint32_t elen, nelen = 0, indirect_ext_len = 0, lenalloc;
int8_t etype;
sector_t first_block = inode->i_size >> inode->i_sb->s_blocksize_bits, offset;
loff_t byte_offset;
int adsize;
if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_SHORT)
adsize = sizeof(short_ad);
else if (UDF_I_ALLOCTYPE(inode) == ICBTAG_FLAG_AD_LONG)
adsize = sizeof(long_ad);
else
BUG();
etype = inode_bmap(inode, first_block, &epos, &eloc, &elen, &offset);
byte_offset = (offset << inode->i_sb->s_blocksize_bits) + (inode->i_size & (inode->i_sb->s_blocksize-1));
if (etype != -1)
{
epos.offset -= adsize;
extent_trunc(inode, &epos, eloc, etype, elen, byte_offset);
epos.offset += adsize;
if (byte_offset)
lenalloc = epos.offset;
else
lenalloc = epos.offset - adsize;
if (!epos.bh)
lenalloc -= udf_file_entry_alloc_offset(inode);
else
lenalloc -= sizeof(struct allocExtDesc);
while ((etype = udf_current_aext(inode, &epos, &eloc, &elen, 0)) != -1)
{
if (etype == (EXT_NEXT_EXTENT_ALLOCDECS >> 30))
{
udf_write_aext(inode, &epos, neloc, nelen, 0);
if (indirect_ext_len)
{
/* We managed to free all extents in the
* indirect extent - free it too */
if (!epos.bh)
BUG();
udf_free_blocks(inode->i_sb, inode, epos.block, 0, indirect_ext_len);
}
else
{
if (!epos.bh)
{
UDF_I_LENALLOC(inode) = lenalloc;
mark_inode_dirty(inode);
}
else
{
struct allocExtDesc *aed = (struct allocExtDesc *)(epos.bh->b_data);
aed->lengthAllocDescs = cpu_to_le32(lenalloc);
if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
udf_update_tag(epos.bh->b_data, lenalloc +
sizeof(struct allocExtDesc));
else
udf_update_tag(epos.bh->b_data, sizeof(struct allocExtDesc));
mark_buffer_dirty_inode(epos.bh, inode);
}
}
brelse(epos.bh);
epos.offset = sizeof(struct allocExtDesc);
epos.block = eloc;
epos.bh = udf_tread(inode->i_sb, udf_get_lb_pblock(inode->i_sb, eloc, 0));
if (elen)
indirect_ext_len = (elen +
inode->i_sb->s_blocksize - 1) >>
inode->i_sb->s_blocksize_bits;
else
indirect_ext_len = 1;
}
else
{
extent_trunc(inode, &epos, eloc, etype, elen, 0);
epos.offset += adsize;
}
}
if (indirect_ext_len)
{
if (!epos.bh)
BUG();
udf_free_blocks(inode->i_sb, inode, epos.block, 0, indirect_ext_len);
}
else
{
if (!epos.bh)
{
UDF_I_LENALLOC(inode) = lenalloc;
mark_inode_dirty(inode);
}
else
{
struct allocExtDesc *aed = (struct allocExtDesc *)(epos.bh->b_data);
aed->lengthAllocDescs = cpu_to_le32(lenalloc);
if (!UDF_QUERY_FLAG(inode->i_sb, UDF_FLAG_STRICT) || UDF_SB_UDFREV(inode->i_sb) >= 0x0201)
udf_update_tag(epos.bh->b_data, lenalloc +
sizeof(struct allocExtDesc));
else
udf_update_tag(epos.bh->b_data, sizeof(struct allocExtDesc));
mark_buffer_dirty_inode(epos.bh, inode);
}
}
}
else if (inode->i_size)
{
if (byte_offset)
{
/*
* OK, there is not extent covering inode->i_size and
* no extent above inode->i_size => truncate is
* extending the file by 'offset'.
*/
if ((!epos.bh && epos.offset == udf_file_entry_alloc_offset(inode)) ||
(epos.bh && epos.offset == sizeof(struct allocExtDesc))) {
/* File has no extents at all! */
memset(&eloc, 0x00, sizeof(kernel_lb_addr));
elen = EXT_NOT_RECORDED_NOT_ALLOCATED | byte_offset;
udf_add_aext(inode, &epos, eloc, elen, 1);
}
else {
epos.offset -= adsize;
etype = udf_next_aext(inode, &epos, &eloc, &elen, 1);
if (etype == (EXT_NOT_RECORDED_NOT_ALLOCATED >> 30))
{
epos.offset -= adsize;
elen = EXT_NOT_RECORDED_NOT_ALLOCATED | (elen + byte_offset);
udf_write_aext(inode, &epos, eloc, elen, 0);
}
else if (etype == (EXT_NOT_RECORDED_ALLOCATED >> 30))
{
kernel_lb_addr neloc = { 0, 0 };
epos.offset -= adsize;
nelen = EXT_NOT_RECORDED_NOT_ALLOCATED |
((elen + byte_offset + inode->i_sb->s_blocksize - 1) &
~(inode->i_sb->s_blocksize - 1));
udf_write_aext(inode, &epos, neloc, nelen, 1);
udf_add_aext(inode, &epos, eloc, (etype << 30) | elen, 1);
}
else
{
if (elen & (inode->i_sb->s_blocksize - 1))
{
epos.offset -= adsize;
elen = EXT_RECORDED_ALLOCATED |
((elen + inode->i_sb->s_blocksize - 1) &
~(inode->i_sb->s_blocksize - 1));
udf_write_aext(inode, &epos, eloc, elen, 1);
}
memset(&eloc, 0x00, sizeof(kernel_lb_addr));
elen = EXT_NOT_RECORDED_NOT_ALLOCATED | byte_offset;
udf_add_aext(inode, &epos, eloc, elen, 1);
}
}
}
}
UDF_I_LENEXTENTS(inode) = inode->i_size;
brelse(epos.bh);
}
|
