migration/file.c

   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 }