xref: /qemu/migration/file.c (revision ec6f3fc3) 
1 /*
2  * Copyright (c) 2021-2023 Oracle and/or its affiliates.
3  *
4  * This work is licensed under the terms of the GNU GPL, version 2 or later.
5  * See the COPYING file in the top-level directory.
6  */
7 
8 #include "qemu/osdep.h"
9 #include "qemu/cutils.h"
10 #include "qapi/error.h"
11 #include "channel.h"
12 #include "file.h"
13 #include "migration.h"
14 #include "io/channel-file.h"
15 #include "io/channel-util.h"
16 #include "trace.h"
17 
18 #define OFFSET_OPTION ",offset="
19 
20 /* Remove the offset option from @filespec and return it in @offsetp. */
21 
22 int file_parse_offset(char *filespec, uint64_t *offsetp, Error **errp)
23 {
24     char *option = strstr(filespec, OFFSET_OPTION);
25     int ret;
26 
27     if (option) {
28         *option = 0;
29         option += sizeof(OFFSET_OPTION) - 1;
30         ret = qemu_strtosz(option, NULL, offsetp);
31         if (ret) {
32             error_setg_errno(errp, -ret, "file URI has bad offset %s", option);
33             return -1;
34         }
35     }
36     return 0;
37 }
38 
39 void file_start_outgoing_migration(MigrationState *s,
40                                    FileMigrationArgs *file_args, Error **errp)
41 {
42     g_autoptr(QIOChannelFile) fioc = NULL;
43     g_autofree char *filename = g_strdup(file_args->filename);
44     uint64_t offset = file_args->offset;
45     QIOChannel *ioc;
46 
47     trace_migration_file_outgoing(filename);
48 
49     fioc = qio_channel_file_new_path(filename, O_CREAT | O_WRONLY | O_TRUNC,
50                                      0600, errp);
51     if (!fioc) {
52         return;
53     }
54 
55     ioc = QIO_CHANNEL(fioc);
56     if (offset && qio_channel_io_seek(ioc, offset, SEEK_SET, errp) < 0) {
57         return;
58     }
59     qio_channel_set_name(ioc, "migration-file-outgoing");
60     migration_channel_connect(s, ioc, NULL, NULL);
61 }
62 
63 static gboolean file_accept_incoming_migration(QIOChannel *ioc,
64                                                GIOCondition condition,
65                                                gpointer opaque)
66 {
67     migration_channel_process_incoming(ioc);
68     object_unref(OBJECT(ioc));
69     return G_SOURCE_REMOVE;
70 }
71 
72 void file_start_incoming_migration(FileMigrationArgs *file_args, Error **errp)
73 {
74     g_autofree char *filename = g_strdup(file_args->filename);
75     QIOChannelFile *fioc = NULL;
76     uint64_t offset = file_args->offset;
77     QIOChannel *ioc;
78 
79     trace_migration_file_incoming(filename);
80 
81     fioc = qio_channel_file_new_path(filename, O_RDONLY, 0, errp);
82     if (!fioc) {
83         return;
84     }
85 
86     ioc = QIO_CHANNEL(fioc);
87     if (offset && qio_channel_io_seek(ioc, offset, SEEK_SET, errp) < 0) {
88         return;
89     }
90     qio_channel_set_name(QIO_CHANNEL(ioc), "migration-file-incoming");
91     qio_channel_add_watch_full(ioc, G_IO_IN,
92                                file_accept_incoming_migration,
93                                NULL, NULL,
94                                g_main_context_get_thread_default());
95 }
96