root / migration-fd.c @ 19bf7c87
History | View | Annotate | Download (2.8 kB)
1 |
/*
|
---|---|
2 |
* QEMU live migration via generic fd
|
3 |
*
|
4 |
* Copyright Red Hat, Inc. 2009
|
5 |
*
|
6 |
* Authors:
|
7 |
* Chris Lalancette <clalance@redhat.com>
|
8 |
*
|
9 |
* This work is licensed under the terms of the GNU GPL, version 2. See
|
10 |
* the COPYING file in the top-level directory.
|
11 |
*
|
12 |
*/
|
13 |
|
14 |
#include "qemu-common.h" |
15 |
#include "qemu_socket.h" |
16 |
#include "migration.h" |
17 |
#include "monitor.h" |
18 |
#include "qemu-char.h" |
19 |
#include "buffered_file.h" |
20 |
#include "block.h" |
21 |
#include "qemu_socket.h" |
22 |
|
23 |
//#define DEBUG_MIGRATION_FD
|
24 |
|
25 |
#ifdef DEBUG_MIGRATION_FD
|
26 |
#define DPRINTF(fmt, ...) \
|
27 |
do { printf("migration-fd: " fmt, ## __VA_ARGS__); } while (0) |
28 |
#else
|
29 |
#define DPRINTF(fmt, ...) \
|
30 |
do { } while (0) |
31 |
#endif
|
32 |
|
33 |
static int fd_errno(MigrationState *s) |
34 |
{ |
35 |
return errno;
|
36 |
} |
37 |
|
38 |
static int fd_write(MigrationState *s, const void * buf, size_t size) |
39 |
{ |
40 |
return write(s->fd, buf, size);
|
41 |
} |
42 |
|
43 |
static int fd_close(MigrationState *s) |
44 |
{ |
45 |
struct stat st;
|
46 |
int ret;
|
47 |
|
48 |
DPRINTF("fd_close\n");
|
49 |
if (s->fd != -1) { |
50 |
ret = fstat(s->fd, &st); |
51 |
if (ret == 0 && S_ISREG(st.st_mode)) { |
52 |
/*
|
53 |
* If the file handle is a regular file make sure the
|
54 |
* data is flushed to disk before signaling success.
|
55 |
*/
|
56 |
ret = fsync(s->fd); |
57 |
if (ret != 0) { |
58 |
ret = -errno; |
59 |
perror("migration-fd: fsync");
|
60 |
return ret;
|
61 |
} |
62 |
} |
63 |
ret = close(s->fd); |
64 |
s->fd = -1;
|
65 |
if (ret != 0) { |
66 |
ret = -errno; |
67 |
perror("migration-fd: close");
|
68 |
return ret;
|
69 |
} |
70 |
} |
71 |
return 0; |
72 |
} |
73 |
|
74 |
int fd_start_outgoing_migration(MigrationState *s, const char *fdname) |
75 |
{ |
76 |
s->fd = monitor_get_fd(s->mon, fdname); |
77 |
if (s->fd == -1) { |
78 |
DPRINTF("fd_migration: invalid file descriptor identifier\n");
|
79 |
goto err_after_get_fd;
|
80 |
} |
81 |
|
82 |
if (fcntl(s->fd, F_SETFL, O_NONBLOCK) == -1) { |
83 |
DPRINTF("Unable to set nonblocking mode on file descriptor\n");
|
84 |
goto err_after_open;
|
85 |
} |
86 |
|
87 |
s->get_error = fd_errno; |
88 |
s->write = fd_write; |
89 |
s->close = fd_close; |
90 |
|
91 |
migrate_fd_connect(s); |
92 |
return 0; |
93 |
|
94 |
err_after_open:
|
95 |
close(s->fd); |
96 |
err_after_get_fd:
|
97 |
return -1; |
98 |
} |
99 |
|
100 |
static void fd_accept_incoming_migration(void *opaque) |
101 |
{ |
102 |
QEMUFile *f = opaque; |
103 |
|
104 |
process_incoming_migration(f); |
105 |
qemu_set_fd_handler2(qemu_stdio_fd(f), NULL, NULL, NULL, NULL); |
106 |
qemu_fclose(f); |
107 |
} |
108 |
|
109 |
int fd_start_incoming_migration(const char *infd) |
110 |
{ |
111 |
int fd;
|
112 |
QEMUFile *f; |
113 |
|
114 |
DPRINTF("Attempting to start an incoming migration via fd\n");
|
115 |
|
116 |
fd = strtol(infd, NULL, 0); |
117 |
f = qemu_fdopen(fd, "rb");
|
118 |
if(f == NULL) { |
119 |
DPRINTF("Unable to apply qemu wrapper to file descriptor\n");
|
120 |
return -errno;
|
121 |
} |
122 |
|
123 |
qemu_set_fd_handler2(fd, NULL, fd_accept_incoming_migration, NULL, f); |
124 |
|
125 |
return 0; |
126 |
} |