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
|
Index: qemu/block-qcow.c
===================================================================
RCS file: /sources/qemu/qemu/block-qcow.c,v
retrieving revision 1.15
retrieving revision 1.16
diff -u -p -u -p -r1.15 -r1.16
--- block-qcow.c 11 Nov 2007 02:51:16 -0000 1.15
+++ block-qcow.c 11 Mar 2008 17:17:58 -0000 1.16
@@ -95,7 +95,7 @@ static int qcow_open(BlockDriverState *b
int len, i, shift, ret;
QCowHeader header;
- ret = bdrv_file_open(&s->hd, filename, flags);
+ ret = bdrv_file_open(&s->hd, filename, flags | BDRV_O_AUTOGROW);
if (ret < 0)
return ret;
if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header))
Index: qemu/block-qcow2.c
===================================================================
RCS file: /sources/qemu/qemu/block-qcow2.c,v
retrieving revision 1.10
retrieving revision 1.11
diff -u -p -u -p -r1.10 -r1.11
--- block-qcow2.c 11 Nov 2007 02:51:16 -0000 1.10
+++ block-qcow2.c 11 Mar 2008 17:17:58 -0000 1.11
@@ -191,7 +191,7 @@ static int qcow_open(BlockDriverState *b
int len, i, shift, ret;
QCowHeader header;
- ret = bdrv_file_open(&s->hd, filename, flags);
+ ret = bdrv_file_open(&s->hd, filename, flags | BDRV_O_AUTOGROW);
if (ret < 0)
return ret;
if (bdrv_pread(s->hd, 0, &header, sizeof(header)) != sizeof(header))
Index: qemu/block-vmdk.c
===================================================================
RCS file: /sources/qemu/qemu/block-vmdk.c,v
retrieving revision 1.19
retrieving revision 1.20
diff -u -p -u -p -r1.19 -r1.20
--- block-vmdk.c 14 Jan 2008 03:48:37 -0000 1.19
+++ block-vmdk.c 11 Mar 2008 17:17:58 -0000 1.20
@@ -378,7 +378,7 @@ static int vmdk_open(BlockDriverState *b
flags = BDRV_O_RDONLY;
fprintf(stderr, "(VMDK) image open: flags=0x%x filename=%s\n", flags, bs->filename);
- ret = bdrv_file_open(&s->hd, filename, flags);
+ ret = bdrv_file_open(&s->hd, filename, flags | BDRV_O_AUTOGROW);
if (ret < 0)
return ret;
if (bdrv_pread(s->hd, 0, &magic, sizeof(magic)) != sizeof(magic))
Index: qemu/block.c
@@ -24,6 +24,9 @@
#include "qemu-common.h"
#ifndef QEMU_IMG
#include "console.h"
+extern int vm_running;
+#else
+int vm_running = 0;
#endif
#include "block_int.h"
@@ -124,6 +128,75 @@
}
}
+static int bdrv_rd_badreq_sectors(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors)
+{
+ if (!vm_running)
+ return 0;
+
+ return
+ nb_sectors < 0 ||
+ sector_num < 0 ||
+ nb_sectors > bs->total_sectors ||
+ sector_num > bs->total_sectors - nb_sectors;
+}
+
+static int bdrv_rd_badreq_bytes(BlockDriverState *bs,
+ int64_t offset, int count)
+{
+ int64_t size = bs->total_sectors << SECTOR_BITS;
+
+ if (!vm_running)
+ return 0;
+
+ return
+ count < 0 ||
+ size < 0 ||
+ count > size ||
+ offset > size - count;
+}
+
+static int bdrv_wr_badreq_sectors(BlockDriverState *bs,
+ int64_t sector_num, int nb_sectors)
+{
+
+ if (!vm_running)
+ return 0;
+
+ if (sector_num < 0 ||
+ nb_sectors < 0)
+ return 1;
+
+ if (sector_num > bs->total_sectors - nb_sectors) {
+ if (bs->autogrow)
+ bs->total_sectors = sector_num + nb_sectors;
+ else
+ return 1;
+ }
+ return 0;
+}
+
+static int bdrv_wr_badreq_bytes(BlockDriverState *bs,
+ int64_t offset, int count)
+{
+ int64_t size = bs->total_sectors << SECTOR_BITS;
+
+ if (!vm_running)
+ return 0;
+
+ if (count < 0 ||
+ offset < 0)
+ return 1;
+
+ if (offset > size - count) {
+ if (bs->autogrow)
+ bs->total_sectors = (offset + count + SECTOR_SIZE - 1) >> SECTOR_BITS;
+ else
+ return 1;
+ }
+ return 0;
+}
+
static void bdrv_register(BlockDriver *bdrv)
{
@@ -335,6 +389,10 @@ int bdrv_open2(BlockDriverState *bs, con
bs->read_only = 0;
bs->is_temporary = 0;
bs->encrypted = 0;
+ bs->autogrow = 0;
+
+ if (flags & BDRV_O_AUTOGROW)
+ bs->autogrow = 1;
if (flags & BDRV_O_SNAPSHOT) {
BlockDriverState *bs1;
@@ -379,6 +437,7 @@ int bdrv_open2(BlockDriverState *bs, con
}
bs->drv = drv;
bs->opaque = qemu_mallocz(drv->instance_size);
+ bs->total_sectors = 0; /* driver will set if it does not do getlength */
if (bs->opaque == NULL && drv->instance_size > 0)
return -1;
/* Note: for compatibility, we open disk image files as RDWR, and
@@ -444,6 +503,7 @@ void bdrv_close(BlockDriverState *bs)
bs->drv = NULL;
/* call the change callback */
+ bs->total_sectors = 0;
bs->media_changed = 1;
if (bs->change_cb)
bs->change_cb(bs->change_opaque);
@@ -509,6 +569,8 @@ int bdrv_read(BlockDriverState *bs, int6
if (!drv)
return -ENOMEDIUM;
+ if (bdrv_rd_badreq_sectors(bs, sector_num, nb_sectors))
+ return -EDOM;
if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
memcpy(buf, bs->boot_sector_data, 512);
sector_num++;
@@ -549,6 +611,8 @@ int bdrv_write(BlockDriverState *bs, int
return -ENOMEDIUM;
if (bs->read_only)
return -EACCES;
+ if (bdrv_wr_badreq_sectors(bs, sector_num, nb_sectors))
+ return -EDOM;
if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
memcpy(bs->boot_sector_data, buf, 512);
}
@@ -674,6 +738,8 @@ int bdrv_pread(BlockDriverState *bs, int
return -ENOMEDIUM;
if (!drv->bdrv_pread)
return bdrv_pread_em(bs, offset, buf1, count1);
+ if (bdrv_rd_badreq_bytes(bs, offset, count1))
+ return -EDOM;
return drv->bdrv_pread(bs, offset, buf1, count1);
}
@@ -689,6 +755,8 @@ int bdrv_pwrite(BlockDriverState *bs, in
return -ENOMEDIUM;
if (!drv->bdrv_pwrite)
return bdrv_pwrite_em(bs, offset, buf1, count1);
+ if (bdrv_wr_badreq_bytes(bs, offset, count1))
+ return -EDOM;
return drv->bdrv_pwrite(bs, offset, buf1, count1);
}
@@ -955,6 +1023,8 @@ int bdrv_write_compressed(BlockDriverSta
return -ENOMEDIUM;
if (!drv->bdrv_write_compressed)
return -ENOTSUP;
+ if (bdrv_wr_badreq_sectors(bs, sector_num, nb_sectors))
+ return -EDOM;
return drv->bdrv_write_compressed(bs, sector_num, buf, nb_sectors);
}
@@ -1101,6 +1171,8 @@ BlockDriverAIOCB *bdrv_aio_read(BlockDri
if (!drv)
return NULL;
+ if (bdrv_rd_badreq_sectors(bs, sector_num, nb_sectors))
+ return NULL;
/* XXX: we assume that nb_sectors == 0 is suppored by the async read */
if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
@@ -1132,6 +1204,8 @@ BlockDriverAIOCB *bdrv_aio_write(BlockDr
return NULL;
if (bs->read_only)
return NULL;
+ if (bdrv_wr_badreq_sectors(bs, sector_num, nb_sectors))
+ return NULL;
if (sector_num == 0 && bs->boot_sector_enabled && nb_sectors > 0) {
memcpy(bs->boot_sector_data, buf, 512);
}
Index: qemu/block.h
===================================================================
RCS file: /sources/qemu/qemu/block.h,v
retrieving revision 1.6
retrieving revision 1.7
diff -u -p -u -p -r1.6 -r1.7
--- block.h 24 Dec 2007 16:10:43 -0000 1.6
+++ block.h 11 Mar 2008 17:17:59 -0000 1.7
@@ -45,6 +45,7 @@ typedef struct QEMUSnapshotInfo {
it (default for
bdrv_file_open()) */
#define BDRV_O_DIRECT 0x0020
+#define BDRV_O_AUTOGROW 0x0040 /* Allow backing file to extend when writing past end of file */
#ifndef QEMU_IMG
void bdrv_info(void);
Index: qemu/block_int.h
===================================================================
RCS file: /sources/qemu/qemu/block_int.h,v
retrieving revision 1.16
retrieving revision 1.17
diff -u -p -u -p -r1.16 -r1.17
--- block_int.h 24 Dec 2007 16:10:43 -0000 1.16
+++ block_int.h 11 Mar 2008 17:17:59 -0000 1.17
@@ -97,6 +97,7 @@ struct BlockDriverState {
int locked; /* if true, the media cannot temporarily be ejected */
int encrypted; /* if true, the media is encrypted */
int sg; /* if true, the device is a /dev/sg* */
+ int autogrow; /* if true, the backing store can auto-extend to allocate new extents */
/* event callback when inserting/removing */
void (*change_cb)(void *opaque);
void *change_opaque;
|
