1 /*
2 * QEMU live migration
3 *
4 * Copyright IBM, Corp. 2008
5 * Copyright Dell MessageOne 2008
6 *
7 * Authors:
8 * Anthony Liguori <aliguori@us.ibm.com>
9 * Charles Duffy <charles_duffy@messageone.com>
10 *
11 * This work is licensed under the terms of the GNU GPL, version 2. See
12 * the COPYING file in the top-level directory.
13 *
14 */
15
16 #include "qemu-common.h"
17 #include "qemu_socket.h"
18 #include "migration.h"
19 #include "qemu-char.h"
20 #include "sysemu.h"
21 #include "buffered_file.h"
22 #include "block.h"
23
24 //#define DEBUG_MIGRATION_EXEC
25
26 #ifdef DEBUG_MIGRATION_EXEC
27 #define dprintf(fmt, ...) \
28 do { printf("migration-exec: " fmt, ## __VA_ARGS__); } while (0)
29 #else
30 #define dprintf(fmt, ...) \
31 do { } while (0)
32 #endif
33
file_errno(FdMigrationState * s)34 static int file_errno(FdMigrationState *s)
35 {
36 return errno;
37 }
38
file_write(FdMigrationState * s,const void * buf,size_t size)39 static int file_write(FdMigrationState *s, const void * buf, size_t size)
40 {
41 return write(s->fd, buf, size);
42 }
43
exec_close(FdMigrationState * s)44 static int exec_close(FdMigrationState *s)
45 {
46 dprintf("exec_close\n");
47 if (s->opaque) {
48 qemu_fclose(s->opaque);
49 s->opaque = NULL;
50 s->fd = -1;
51 }
52 return 0;
53 }
54
exec_start_outgoing_migration(const char * command,int64_t bandwidth_limit,int detach)55 MigrationState *exec_start_outgoing_migration(const char *command,
56 int64_t bandwidth_limit,
57 int detach)
58 {
59 FdMigrationState *s;
60 FILE *f;
61
62 s = qemu_mallocz(sizeof(*s));
63
64 f = popen(command, "w");
65 if (f == NULL) {
66 dprintf("Unable to popen exec target\n");
67 goto err_after_alloc;
68 }
69
70 s->fd = fileno(f);
71 if (s->fd == -1) {
72 dprintf("Unable to retrieve file descriptor for popen'd handle\n");
73 goto err_after_open;
74 }
75
76 if (fcntl(s->fd, F_SETFD, O_NONBLOCK) == -1) {
77 dprintf("Unable to set nonblocking mode on file descriptor\n");
78 goto err_after_open;
79 }
80
81 s->opaque = qemu_popen(f, "w");
82
83 s->close = exec_close;
84 s->get_error = file_errno;
85 s->write = file_write;
86 s->mig_state.cancel = migrate_fd_cancel;
87 s->mig_state.get_status = migrate_fd_get_status;
88 s->mig_state.release = migrate_fd_release;
89
90 s->state = MIG_STATE_ACTIVE;
91 s->mon_resume = NULL;
92 s->bandwidth_limit = bandwidth_limit;
93
94 if (!detach)
95 migrate_fd_monitor_suspend(s);
96
97 migrate_fd_connect(s);
98 return &s->mig_state;
99
100 err_after_open:
101 pclose(f);
102 err_after_alloc:
103 qemu_free(s);
104 return NULL;
105 }
106
exec_accept_incoming_migration(void * opaque)107 static void exec_accept_incoming_migration(void *opaque)
108 {
109 QEMUFile *f = opaque;
110 int ret;
111
112 vm_stop(0); /* just in case */
113 ret = qemu_loadvm_state(f);
114 if (ret < 0) {
115 fprintf(stderr, "load of migration failed\n");
116 goto err;
117 }
118 qemu_announce_self();
119 dprintf("successfully loaded vm state\n");
120 /* we've successfully migrated, close the fd */
121 qemu_set_fd_handler2(qemu_popen_fd(f), NULL, NULL, NULL, NULL);
122 vm_start();
123
124 err:
125 qemu_fclose(f);
126 }
127
exec_start_incoming_migration(const char * command)128 int exec_start_incoming_migration(const char *command)
129 {
130 QEMUFile *f;
131
132 dprintf("Attempting to start an incoming migration\n");
133 f = qemu_popen_cmd(command, "r");
134 if(f == NULL) {
135 dprintf("Unable to apply qemu wrapper to popen file\n");
136 return -errno;
137 }
138
139 qemu_set_fd_handler2(qemu_popen_fd(f), NULL,
140 exec_accept_incoming_migration, NULL,
141 (void *)(unsigned long)f);
142
143 return 0;
144 }
145