xref: /illumos-kvm-cmd/migration-fd.c (revision 68396ea9)
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 "sysemu.h"
20 #include "buffered_file.h"
21 #include "block.h"
22 #include "qemu_socket.h"
23 
24 //#define DEBUG_MIGRATION_FD
25 
26 #ifdef DEBUG_MIGRATION_FD
27 #define DPRINTF(fmt, ...) \
28     do { printf("migration-fd: " fmt, ## __VA_ARGS__); } while (0)
29 #else
30 #define DPRINTF(fmt, ...) \
31     do { } while (0)
32 #endif
33 
fd_errno(FdMigrationState * s)34 static int fd_errno(FdMigrationState *s)
35 {
36     return errno;
37 }
38 
fd_write(FdMigrationState * s,const void * buf,size_t size)39 static int fd_write(FdMigrationState *s, const void * buf, size_t size)
40 {
41     return write(s->fd, buf, size);
42 }
43 
fd_close(FdMigrationState * s)44 static int fd_close(FdMigrationState *s)
45 {
46     DPRINTF("fd_close\n");
47     if (s->fd != -1) {
48         close(s->fd);
49         s->fd = -1;
50     }
51     return 0;
52 }
53 
fd_start_outgoing_migration(Monitor * mon,const char * fdname,int64_t bandwidth_limit,int detach,int blk,int inc)54 MigrationState *fd_start_outgoing_migration(Monitor *mon,
55 					    const char *fdname,
56 					    int64_t bandwidth_limit,
57 					    int detach,
58 					    int blk,
59 					    int inc)
60 {
61     FdMigrationState *s;
62 
63     s = qemu_mallocz(sizeof(*s));
64 
65     s->fd = monitor_get_fd(mon, fdname);
66     if (s->fd == -1) {
67         DPRINTF("fd_migration: invalid file descriptor identifier\n");
68         goto err_after_alloc;
69     }
70 
71     if (fcntl(s->fd, F_SETFL, O_NONBLOCK) == -1) {
72         DPRINTF("Unable to set nonblocking mode on file descriptor\n");
73         goto err_after_open;
74     }
75 
76     s->get_error = fd_errno;
77     s->write = fd_write;
78     s->close = fd_close;
79     s->mig_state.cancel = migrate_fd_cancel;
80     s->mig_state.get_status = migrate_fd_get_status;
81     s->mig_state.release = migrate_fd_release;
82 
83     s->mig_state.blk = blk;
84     s->mig_state.shared = inc;
85 
86     s->state = MIG_STATE_ACTIVE;
87     s->mon = NULL;
88     s->bandwidth_limit = bandwidth_limit;
89 
90     if (!detach) {
91         migrate_fd_monitor_suspend(s, mon);
92     }
93 
94     migrate_fd_connect(s);
95     return &s->mig_state;
96 
97 err_after_open:
98     close(s->fd);
99 err_after_alloc:
100     qemu_free(s);
101     return NULL;
102 }
103 
fd_accept_incoming_migration(void * opaque)104 static void fd_accept_incoming_migration(void *opaque)
105 {
106     QEMUFile *f = opaque;
107 
108     process_incoming_migration(f);
109     qemu_set_fd_handler2(qemu_stdio_fd(f), NULL, NULL, NULL, NULL);
110     qemu_fclose(f);
111 }
112 
fd_start_incoming_migration(const char * infd)113 int fd_start_incoming_migration(const char *infd)
114 {
115     int fd;
116     QEMUFile *f;
117 
118     DPRINTF("Attempting to start an incoming migration via fd\n");
119 
120     fd = strtol(infd, NULL, 0);
121     f = qemu_fdopen(fd, "rb");
122     if(f == NULL) {
123         DPRINTF("Unable to apply qemu wrapper to file descriptor\n");
124         return -errno;
125     }
126 
127     qemu_set_fd_handler2(fd, NULL, fd_accept_incoming_migration, NULL, f);
128 
129     return 0;
130 }
131