blob: 9b68a2be645f0d56d78e36667c677102b88c4ac3 [file] [log] [blame]
Andrey Shinkevichf41388e2019-12-02 15:15:04 +03001/*
2 * Compress filter block driver
3 *
4 * Copyright (c) 2019 Virtuozzo International GmbH
5 *
6 * Author:
7 * Andrey Shinkevich <andrey.shinkevich@virtuozzo.com>
8 * (based on block/copy-on-read.c by Max Reitz)
9 *
10 * This program is free software; you can redistribute it and/or
11 * modify it under the terms of the GNU General Public License as
12 * published by the Free Software Foundation; either version 2 or
13 * (at your option) any later version of the License.
14 *
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
19 *
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, see <http://www.gnu.org/licenses/>.
22 */
23
24#include "qemu/osdep.h"
Markus Armbrustere2c1c342022-12-21 14:35:49 +010025#include "block/block-io.h"
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030026#include "block/block_int.h"
27#include "qemu/module.h"
28#include "qapi/error.h"
29
30
31static int compress_open(BlockDriverState *bs, QDict *options, int flags,
32 Error **errp)
33{
Vladimir Sementsov-Ogievskiy83930782022-07-26 23:11:21 +030034 int ret = bdrv_open_file_child(NULL, options, "file", bs, errp);
35 if (ret < 0) {
36 return ret;
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030037 }
38
Kevin Wolfa4b740d2023-10-27 17:53:32 +020039 GRAPH_RDLOCK_GUARD_MAINLOOP();
40
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030041 if (!bs->file->bs->drv || !block_driver_can_compress(bs->file->bs->drv)) {
42 error_setg(errp,
43 "Compression is not supported for underlying format: %s",
44 bdrv_get_format_name(bs->file->bs) ?: "(no format)");
45
46 return -ENOTSUP;
47 }
48
49 bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED |
50 (BDRV_REQ_FUA & bs->file->bs->supported_write_flags);
51
52 bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED |
53 ((BDRV_REQ_FUA | BDRV_REQ_MAY_UNMAP | BDRV_REQ_NO_FALLBACK) &
54 bs->file->bs->supported_zero_flags);
55
56 return 0;
57}
58
59
Kevin Wolf8ab81402023-02-03 16:22:02 +010060static int64_t coroutine_fn GRAPH_RDLOCK
61compress_co_getlength(BlockDriverState *bs)
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030062{
Emanuele Giuseppe Espositoc86422c2023-01-13 21:42:04 +010063 return bdrv_co_getlength(bs->file->bs);
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030064}
65
66
Kevin Wolfb9b10c32023-02-03 16:21:50 +010067static int coroutine_fn GRAPH_RDLOCK
68compress_co_preadv_part(BlockDriverState *bs, int64_t offset, int64_t bytes,
69 QEMUIOVector *qiov, size_t qiov_offset,
70 BdrvRequestFlags flags)
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030071{
72 return bdrv_co_preadv_part(bs->file, offset, bytes, qiov, qiov_offset,
73 flags);
74}
75
76
Kevin Wolfb9b10c32023-02-03 16:21:50 +010077static int coroutine_fn GRAPH_RDLOCK
78compress_co_pwritev_part(BlockDriverState *bs, int64_t offset, int64_t bytes,
79 QEMUIOVector *qiov, size_t qiov_offset,
80 BdrvRequestFlags flags)
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030081{
82 return bdrv_co_pwritev_part(bs->file, offset, bytes, qiov, qiov_offset,
83 flags | BDRV_REQ_WRITE_COMPRESSED);
84}
85
86
Kevin Wolfabaf8b72023-02-03 16:21:48 +010087static int coroutine_fn GRAPH_RDLOCK
88compress_co_pwrite_zeroes(BlockDriverState *bs, int64_t offset, int64_t bytes,
89 BdrvRequestFlags flags)
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030090{
91 return bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags);
92}
93
94
Emanuele Giuseppe Esposito9a5a1c62023-02-03 16:21:47 +010095static int coroutine_fn GRAPH_RDLOCK
96compress_co_pdiscard(BlockDriverState *bs, int64_t offset, int64_t bytes)
Andrey Shinkevichf41388e2019-12-02 15:15:04 +030097{
98 return bdrv_co_pdiscard(bs->file, offset, bytes);
99}
100
101
Kevin Wolf79a55862023-10-27 17:53:29 +0200102static void GRAPH_RDLOCK
103compress_refresh_limits(BlockDriverState *bs, Error **errp)
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300104{
105 BlockDriverInfo bdi;
106 int ret;
107
108 if (!bs->file) {
109 return;
110 }
111
112 ret = bdrv_get_info(bs->file->bs, &bdi);
113 if (ret < 0 || bdi.cluster_size == 0) {
114 return;
115 }
116
117 bs->bl.request_alignment = bdi.cluster_size;
118}
119
120
Kevin Wolf79a292e2023-02-03 16:21:58 +0100121static void coroutine_fn GRAPH_RDLOCK
Emanuele Giuseppe Esposito2531b392023-01-13 21:42:09 +0100122compress_co_eject(BlockDriverState *bs, bool eject_flag)
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300123{
Emanuele Giuseppe Esposito2531b392023-01-13 21:42:09 +0100124 bdrv_co_eject(bs->file->bs, eject_flag);
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300125}
126
127
Kevin Wolf79a292e2023-02-03 16:21:58 +0100128static void coroutine_fn GRAPH_RDLOCK
Emanuele Giuseppe Esposito2c752612023-01-13 21:42:10 +0100129compress_co_lock_medium(BlockDriverState *bs, bool locked)
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300130{
Emanuele Giuseppe Esposito2c752612023-01-13 21:42:10 +0100131 bdrv_co_lock_medium(bs->file->bs, locked);
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300132}
133
134
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300135static BlockDriver bdrv_compress = {
136 .format_name = "compress",
137
138 .bdrv_open = compress_open,
Max Reitz69dca432020-05-13 13:05:39 +0200139 .bdrv_child_perm = bdrv_default_perms,
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300140
Emanuele Giuseppe Espositoc86422c2023-01-13 21:42:04 +0100141 .bdrv_co_getlength = compress_co_getlength,
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300142
143 .bdrv_co_preadv_part = compress_co_preadv_part,
144 .bdrv_co_pwritev_part = compress_co_pwritev_part,
145 .bdrv_co_pwrite_zeroes = compress_co_pwrite_zeroes,
146 .bdrv_co_pdiscard = compress_co_pdiscard,
147 .bdrv_refresh_limits = compress_refresh_limits,
148
Emanuele Giuseppe Esposito2531b392023-01-13 21:42:09 +0100149 .bdrv_co_eject = compress_co_eject,
Emanuele Giuseppe Esposito2c752612023-01-13 21:42:10 +0100150 .bdrv_co_lock_medium = compress_co_lock_medium,
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300151
Andrey Shinkevichf41388e2019-12-02 15:15:04 +0300152 .is_filter = true,
153};
154
155static void bdrv_compress_init(void)
156{
157 bdrv_register(&bdrv_compress);
158}
159
160block_init(bdrv_compress_init);