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
|
/*
* Block protocol for record/replay
*
* Copyright (c) 2010-2016 Institute for System Programming
* of the Russian Academy of Sciences.
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "block/block_int.h"
#include "sysemu/replay.h"
#include "qapi/error.h"
typedef struct Request {
Coroutine *co;
QEMUBH *bh;
} Request;
static int blkreplay_open(BlockDriverState *bs, QDict *options, int flags,
Error **errp)
{
Error *local_err = NULL;
int ret;
/* Open the image file */
bs->file = bdrv_open_child(NULL, options, "image",
bs, &child_file, false, &local_err);
if (local_err) {
ret = -EINVAL;
error_propagate(errp, local_err);
goto fail;
}
bs->supported_write_flags = BDRV_REQ_WRITE_UNCHANGED;
bs->supported_zero_flags = BDRV_REQ_WRITE_UNCHANGED;
ret = 0;
fail:
return ret;
}
static int64_t blkreplay_getlength(BlockDriverState *bs)
{
return bdrv_getlength(bs->file->bs);
}
/* This bh is used for synchronization of return from coroutines.
It continues yielded coroutine which then finishes its execution.
BH is called adjusted to some replay checkpoint, therefore
record and replay will always finish coroutines deterministically.
*/
static void blkreplay_bh_cb(void *opaque)
{
Request *req = opaque;
aio_co_wake(req->co);
qemu_bh_delete(req->bh);
g_free(req);
}
static void block_request_create(uint64_t reqid, BlockDriverState *bs,
Coroutine *co)
{
Request *req = g_new(Request, 1);
*req = (Request) {
.co = co,
.bh = aio_bh_new(bdrv_get_aio_context(bs), blkreplay_bh_cb, req),
};
replay_block_event(req->bh, reqid);
}
static int coroutine_fn blkreplay_co_preadv(BlockDriverState *bs,
uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
{
uint64_t reqid = blkreplay_next_id();
int ret = bdrv_co_preadv(bs->file, offset, bytes, qiov, flags);
block_request_create(reqid, bs, qemu_coroutine_self());
qemu_coroutine_yield();
return ret;
}
static int coroutine_fn blkreplay_co_pwritev(BlockDriverState *bs,
uint64_t offset, uint64_t bytes, QEMUIOVector *qiov, int flags)
{
uint64_t reqid = blkreplay_next_id();
int ret = bdrv_co_pwritev(bs->file, offset, bytes, qiov, flags);
block_request_create(reqid, bs, qemu_coroutine_self());
qemu_coroutine_yield();
return ret;
}
static int coroutine_fn blkreplay_co_pwrite_zeroes(BlockDriverState *bs,
int64_t offset, int bytes, BdrvRequestFlags flags)
{
uint64_t reqid = blkreplay_next_id();
int ret = bdrv_co_pwrite_zeroes(bs->file, offset, bytes, flags);
block_request_create(reqid, bs, qemu_coroutine_self());
qemu_coroutine_yield();
return ret;
}
static int coroutine_fn blkreplay_co_pdiscard(BlockDriverState *bs,
int64_t offset, int bytes)
{
uint64_t reqid = blkreplay_next_id();
int ret = bdrv_co_pdiscard(bs->file, offset, bytes);
block_request_create(reqid, bs, qemu_coroutine_self());
qemu_coroutine_yield();
return ret;
}
static int coroutine_fn blkreplay_co_flush(BlockDriverState *bs)
{
uint64_t reqid = blkreplay_next_id();
int ret = bdrv_co_flush(bs->file->bs);
block_request_create(reqid, bs, qemu_coroutine_self());
qemu_coroutine_yield();
return ret;
}
static BlockDriver bdrv_blkreplay = {
.format_name = "blkreplay",
.instance_size = 0,
.bdrv_open = blkreplay_open,
.bdrv_child_perm = bdrv_filter_default_perms,
.bdrv_getlength = blkreplay_getlength,
.bdrv_co_preadv = blkreplay_co_preadv,
.bdrv_co_pwritev = blkreplay_co_pwritev,
.bdrv_co_pwrite_zeroes = blkreplay_co_pwrite_zeroes,
.bdrv_co_pdiscard = blkreplay_co_pdiscard,
.bdrv_co_flush = blkreplay_co_flush,
};
static void bdrv_blkreplay_init(void)
{
bdrv_register(&bdrv_blkreplay);
}
block_init(bdrv_blkreplay_init);
|
