jcs.org
qemu with hax to log dma reads & writes
jcs.org/2018/11/12/vfio
dmg: Move libbz2 code to dmg-bz2.so
dmg.o was moved to block-obj-m in 5505e8b76 to become a separate module,
so that its reference to libbz2, since 6b383c08c, doesn't add an extra
library to the main executable.
Until recently, commit 06e60f70a (blockdev: Add dynamic module loading
for block drivers) moved it back to block-obj-y to simplify the design
of dynamic loading of block modules. But we don't want to lose the
feature of less library dependency on the main executable.
The solution here is to move only the bz2 related code to a separate
DSO file, and load it when dmg_open is called.
dmg_probe doesn't depend on bz2 support to work, and is the only code in
this file which can run before dmg_open.
While we are at it, fix the unhelpful cast of last argument passed to
dmg_uncompress_bz2.
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1473043845-13197-4-git-send-email-famz@redhat.com
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
+139
-53
+2
-1
block/Makefile.objs
+2
-1
block/Makefile.objs
···
41
41
ssh.o-cflags := $(LIBSSH2_CFLAGS)
42
42
ssh.o-libs := $(LIBSSH2_LIBS)
43
43
archipelago.o-libs := $(ARCHIPELAGO_LIBS)
44
-
dmg.o-libs := $(BZIP2_LIBS)
44
+
block-obj-$(if $(CONFIG_BZIP2),m,n) += dmg-bz2.o
45
+
dmg-bz2.o-libs := $(BZIP2_LIBS)
45
46
qcow.o-libs := -lz
46
47
linux-aio.o-libs := -laio
+61
block/dmg-bz2.c
+61
block/dmg-bz2.c
···
1
+
/*
2
+
* DMG bzip2 uncompression
3
+
*
4
+
* Copyright (c) 2004 Johannes E. Schindelin
5
+
* Copyright (c) 2016 Red Hat, Inc.
6
+
*
7
+
* Permission is hereby granted, free of charge, to any person obtaining a copy
8
+
* of this software and associated documentation files (the "Software"), to deal
9
+
* in the Software without restriction, including without limitation the rights
10
+
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11
+
* copies of the Software, and to permit persons to whom the Software is
12
+
* furnished to do so, subject to the following conditions:
13
+
*
14
+
* The above copyright notice and this permission notice shall be included in
15
+
* all copies or substantial portions of the Software.
16
+
*
17
+
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18
+
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19
+
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20
+
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21
+
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22
+
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23
+
* THE SOFTWARE.
24
+
*/
25
+
#include "qemu/osdep.h"
26
+
#include "qemu-common.h"
27
+
#include "dmg.h"
28
+
#include <bzlib.h>
29
+
30
+
static int dmg_uncompress_bz2_do(char *next_in, unsigned int avail_in,
31
+
char *next_out, unsigned int avail_out)
32
+
{
33
+
int ret;
34
+
uint64_t total_out;
35
+
bz_stream bzstream = {};
36
+
37
+
ret = BZ2_bzDecompressInit(&bzstream, 0, 0);
38
+
if (ret != BZ_OK) {
39
+
return -1;
40
+
}
41
+
bzstream.next_in = next_in;
42
+
bzstream.avail_in = avail_in;
43
+
bzstream.next_out = next_out;
44
+
bzstream.avail_out = avail_out;
45
+
ret = BZ2_bzDecompress(&bzstream);
46
+
total_out = ((uint64_t)bzstream.total_out_hi32 << 32) +
47
+
bzstream.total_out_lo32;
48
+
BZ2_bzDecompressEnd(&bzstream);
49
+
if (ret != BZ_STREAM_END ||
50
+
total_out != avail_out) {
51
+
return -1;
52
+
}
53
+
return 0;
54
+
}
55
+
56
+
__attribute__((constructor))
57
+
static void dmg_bz2_init(void)
58
+
{
59
+
assert(!dmg_uncompress_bz2);
60
+
dmg_uncompress_bz2 = dmg_uncompress_bz2_do;
61
+
}
+17
-52
block/dmg.c
+17
-52
block/dmg.c
···
28
28
#include "qemu/bswap.h"
29
29
#include "qemu/error-report.h"
30
30
#include "qemu/module.h"
31
-
#include <zlib.h>
32
-
#ifdef CONFIG_BZIP2
33
-
#include <bzlib.h>
34
-
#endif
31
+
#include "dmg.h"
32
+
33
+
int (*dmg_uncompress_bz2)(char *next_in, unsigned int avail_in,
34
+
char *next_out, unsigned int avail_out);
35
35
36
36
enum {
37
37
/* Limit chunk sizes to prevent unreasonable amounts of memory being used
···
40
40
DMG_LENGTHS_MAX = 64 * 1024 * 1024, /* 64 MB */
41
41
DMG_SECTORCOUNTS_MAX = DMG_LENGTHS_MAX / 512,
42
42
};
43
-
44
-
typedef struct BDRVDMGState {
45
-
CoMutex lock;
46
-
/* each chunk contains a certain number of sectors,
47
-
* offsets[i] is the offset in the .dmg file,
48
-
* lengths[i] is the length of the compressed chunk,
49
-
* sectors[i] is the sector beginning at offsets[i],
50
-
* sectorcounts[i] is the number of sectors in that chunk,
51
-
* the sectors array is ordered
52
-
* 0<=i<n_chunks */
53
-
54
-
uint32_t n_chunks;
55
-
uint32_t* types;
56
-
uint64_t* offsets;
57
-
uint64_t* lengths;
58
-
uint64_t* sectors;
59
-
uint64_t* sectorcounts;
60
-
uint32_t current_chunk;
61
-
uint8_t *compressed_chunk;
62
-
uint8_t *uncompressed_chunk;
63
-
z_stream zstream;
64
-
#ifdef CONFIG_BZIP2
65
-
bz_stream bzstream;
66
-
#endif
67
-
} BDRVDMGState;
68
43
69
44
static int dmg_probe(const uint8_t *buf, int buf_size, const char *filename)
70
45
{
···
210
185
case 0x00000001: /* uncompressed */
211
186
case 0x00000002: /* zeroes */
212
187
case 0x80000005: /* zlib */
213
-
#ifdef CONFIG_BZIP2
188
+
return true;
214
189
case 0x80000006: /* bzip2 */
215
-
#endif
216
-
return true;
190
+
return !!dmg_uncompress_bz2;
217
191
default:
218
192
return false;
219
193
}
···
439
413
int64_t offset;
440
414
int ret;
441
415
416
+
block_module_load_one("dmg-bz2");
442
417
bs->read_only = true;
443
418
444
419
s->n_chunks = 0;
···
587
562
if (!is_sector_in_chunk(s, s->current_chunk, sector_num)) {
588
563
int ret;
589
564
uint32_t chunk = search_chunk(s, sector_num);
590
-
#ifdef CONFIG_BZIP2
591
-
uint64_t total_out;
592
-
#endif
593
565
594
566
if (chunk >= s->n_chunks) {
595
567
return -1;
···
620
592
return -1;
621
593
}
622
594
break; }
623
-
#ifdef CONFIG_BZIP2
624
595
case 0x80000006: /* bzip2 compressed */
596
+
if (!dmg_uncompress_bz2) {
597
+
break;
598
+
}
625
599
/* we need to buffer, because only the chunk as whole can be
626
600
* inflated. */
627
601
ret = bdrv_pread(bs->file, s->offsets[chunk],
···
630
604
return -1;
631
605
}
632
606
633
-
ret = BZ2_bzDecompressInit(&s->bzstream, 0, 0);
634
-
if (ret != BZ_OK) {
635
-
return -1;
636
-
}
637
-
s->bzstream.next_in = (char *)s->compressed_chunk;
638
-
s->bzstream.avail_in = (unsigned int) s->lengths[chunk];
639
-
s->bzstream.next_out = (char *)s->uncompressed_chunk;
640
-
s->bzstream.avail_out = (unsigned int) 512 * s->sectorcounts[chunk];
641
-
ret = BZ2_bzDecompress(&s->bzstream);
642
-
total_out = ((uint64_t)s->bzstream.total_out_hi32 << 32) +
643
-
s->bzstream.total_out_lo32;
644
-
BZ2_bzDecompressEnd(&s->bzstream);
645
-
if (ret != BZ_STREAM_END ||
646
-
total_out != 512 * s->sectorcounts[chunk]) {
647
-
return -1;
607
+
ret = dmg_uncompress_bz2((char *)s->compressed_chunk,
608
+
(unsigned int) s->lengths[chunk],
609
+
(char *)s->uncompressed_chunk,
610
+
(unsigned int)
611
+
(512 * s->sectorcounts[chunk]));
612
+
if (ret < 0) {
613
+
return ret;
648
614
}
649
615
break;
650
-
#endif /* CONFIG_BZIP2 */
651
616
case 1: /* copy */
652
617
ret = bdrv_pread(bs->file, s->offsets[chunk],
653
618
s->uncompressed_chunk, s->lengths[chunk]);
+59
block/dmg.h
+59
block/dmg.h
···
1
+
/*
2
+
* Header for DMG driver
3
+
*
4
+
* Copyright (c) 2004-2006 Fabrice Bellard
5
+
* Copyright (c) 2016 Red hat, Inc.
6
+
*
7
+
* Permission is hereby granted, free of charge, to any person obtaining a copy
8
+
* of this software and associated documentation files (the "Software"), to deal
9
+
* in the Software without restriction, including without limitation the rights
10
+
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
11
+
* copies of the Software, and to permit persons to whom the Software is
12
+
* furnished to do so, subject to the following conditions:
13
+
*
14
+
* The above copyright notice and this permission notice shall be included in
15
+
* all copies or substantial portions of the Software.
16
+
*
17
+
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
18
+
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
19
+
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
20
+
* THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
21
+
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
22
+
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
23
+
* THE SOFTWARE.
24
+
*/
25
+
26
+
#ifndef BLOCK_DMG_H
27
+
#define BLOCK_DMG_H
28
+
29
+
#include "qemu/osdep.h"
30
+
#include "qemu-common.h"
31
+
#include "block/block_int.h"
32
+
#include <zlib.h>
33
+
34
+
typedef struct BDRVDMGState {
35
+
CoMutex lock;
36
+
/* each chunk contains a certain number of sectors,
37
+
* offsets[i] is the offset in the .dmg file,
38
+
* lengths[i] is the length of the compressed chunk,
39
+
* sectors[i] is the sector beginning at offsets[i],
40
+
* sectorcounts[i] is the number of sectors in that chunk,
41
+
* the sectors array is ordered
42
+
* 0<=i<n_chunks */
43
+
44
+
uint32_t n_chunks;
45
+
uint32_t *types;
46
+
uint64_t *offsets;
47
+
uint64_t *lengths;
48
+
uint64_t *sectors;
49
+
uint64_t *sectorcounts;
50
+
uint32_t current_chunk;
51
+
uint8_t *compressed_chunk;
52
+
uint8_t *uncompressed_chunk;
53
+
z_stream zstream;
54
+
} BDRVDMGState;
55
+
56
+
extern int (*dmg_uncompress_bz2)(char *next_in, unsigned int avail_in,
57
+
char *next_out, unsigned int avail_out);
58
+
59
+
#endif