new file mode 100644
@@ -0,0 +1,21 @@
+/*
+ * Copyright (c) 2021, 2024 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#ifndef MIGRATION_CPR_H
+#define MIGRATION_CPR_H
+
+typedef int (*cpr_walk_fd_cb)(int fd);
+void cpr_save_fd(const char *name, int id, int fd);
+void cpr_delete_fd(const char *name, int id);
+int cpr_find_fd(const char *name, int id);
+int cpr_walk_fd(cpr_walk_fd_cb cb);
+void cpr_resave_fd(const char *name, int id, int fd);
+
+int cpr_state_save(Error **errp);
+int cpr_state_load(Error **errp);
+
+#endif
new file mode 100644
@@ -0,0 +1,188 @@
+/*
+ * Copyright (c) 2021-2024 Oracle and/or its affiliates.
+ *
+ * This work is licensed under the terms of the GNU GPL, version 2 or later.
+ * See the COPYING file in the top-level directory.
+ */
+
+#include "qemu/osdep.h"
+#include "qapi/error.h"
+#include "migration/cpr.h"
+#include "migration/misc.h"
+#include "migration/qemu-file.h"
+#include "migration/savevm.h"
+#include "migration/vmstate.h"
+#include "sysemu/runstate.h"
+#include "trace.h"
+
+/*************************************************************************/
+/* cpr state container for all information to be saved. */
+
+typedef QLIST_HEAD(CprFdList, CprFd) CprFdList;
+
+typedef struct CprState {
+ CprFdList fds;
+} CprState;
+
+static CprState cpr_state;
+
+/****************************************************************************/
+
+typedef struct CprFd {
+ char *name;
+ unsigned int namelen;
+ int id;
+ int fd;
+ QLIST_ENTRY(CprFd) next;
+} CprFd;
+
+static const VMStateDescription vmstate_cpr_fd = {
+ .name = "cpr fd",
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_UINT32(namelen, CprFd),
+ VMSTATE_VBUFFER_ALLOC_UINT32(name, CprFd, 0, NULL, namelen),
+ VMSTATE_INT32(id, CprFd),
+ VMSTATE_INT32(fd, CprFd),
+ VMSTATE_END_OF_LIST()
+ }
+};
+
+void cpr_save_fd(const char *name, int id, int fd)
+{
+ CprFd *elem = g_new0(CprFd, 1);
+
+ trace_cpr_save_fd(name, id, fd);
+ elem->name = g_strdup(name);
+ elem->namelen = strlen(name) + 1;
+ elem->id = id;
+ elem->fd = fd;
+ QLIST_INSERT_HEAD(&cpr_state.fds, elem, next);
+}
+
+static CprFd *find_fd(CprFdList *head, const char *name, int id)
+{
+ CprFd *elem;
+
+ QLIST_FOREACH(elem, head, next) {
+ if (!strcmp(elem->name, name) && elem->id == id) {
+ return elem;
+ }
+ }
+ return NULL;
+}
+
+void cpr_delete_fd(const char *name, int id)
+{
+ CprFd *elem = find_fd(&cpr_state.fds, name, id);
+
+ if (elem) {
+ QLIST_REMOVE(elem, next);
+ g_free(elem->name);
+ g_free(elem);
+ }
+
+ trace_cpr_delete_fd(name, id);
+}
+
+int cpr_find_fd(const char *name, int id)
+{
+ CprFd *elem = find_fd(&cpr_state.fds, name, id);
+ int fd = elem ? elem->fd : -1;
+
+ trace_cpr_find_fd(name, id, fd);
+ return fd;
+}
+
+int cpr_walk_fd(cpr_walk_fd_cb cb)
+{
+ CprFd *elem;
+
+ QLIST_FOREACH(elem, &cpr_state.fds, next) {
+ if (elem->fd >= 0 && cb(elem->fd)) {
+ return 1;
+ }
+ }
+ return 0;
+}
+
+void cpr_resave_fd(const char *name, int id, int fd)
+{
+ CprFd *elem = find_fd(&cpr_state.fds, name, id);
+ int old_fd = elem ? elem->fd : -1;
+
+ if (old_fd < 0) {
+ cpr_save_fd(name, id, fd);
+ } else if (old_fd != fd) {
+ error_setg(&error_fatal,
+ "internal error: cpr fd '%s' id %d value %d "
+ "already saved with a different value %d",
+ name, id, fd, old_fd);
+ }
+}
+/*************************************************************************/
+#define CPR_STATE "CprState"
+
+static const VMStateDescription vmstate_cpr_state = {
+ .name = CPR_STATE,
+ .version_id = 1,
+ .minimum_version_id = 1,
+ .fields = (VMStateField[]) {
+ VMSTATE_QLIST_V(fds, CprState, 1, vmstate_cpr_fd, CprFd, next),
+ VMSTATE_END_OF_LIST()
+ }
+};
+/*************************************************************************/
+
+int cpr_state_save(Error **errp)
+{
+ int ret;
+ QEMUFile *f;
+
+ /* set f based on mode in a later patch in this series */
+ return 0;
+
+ qemu_put_be32(f, QEMU_VM_FILE_MAGIC);
+ qemu_put_be32(f, QEMU_VM_FILE_VERSION);
+
+ ret = vmstate_save_state(f, &vmstate_cpr_state, &cpr_state, 0);
+ if (ret) {
+ error_setg(errp, "vmstate_save_state error %d", ret);
+ }
+
+ qemu_fclose(f);
+ return ret;
+}
+
+int cpr_state_load(Error **errp)
+{
+ int ret;
+ uint32_t v;
+ QEMUFile *f;
+
+ /* set f based on mode in a later patch in this series */
+ return 0;
+
+ v = qemu_get_be32(f);
+ if (v != QEMU_VM_FILE_MAGIC) {
+ error_setg(errp, "Not a migration stream (bad magic %x)", v);
+ qemu_fclose(f);
+ return -EINVAL;
+ }
+ v = qemu_get_be32(f);
+ if (v != QEMU_VM_FILE_VERSION) {
+ error_setg(errp, "Unsupported migration stream version %d", v);
+ qemu_fclose(f);
+ return -ENOTSUP;
+ }
+
+ ret = vmstate_load_state(f, &vmstate_cpr_state, &cpr_state, 1);
+ if (ret) {
+ error_setg(errp, "vmstate_load_state error %d", ret);
+ }
+
+ qemu_fclose(f);
+ return ret;
+}
+
@@ -13,6 +13,7 @@ system_ss.add(files(
'block-dirty-bitmap.c',
'channel.c',
'channel-block.c',
+ 'cpr.c',
'dirtyrate.c',
'exec.c',
'fd.c',
@@ -27,6 +27,7 @@
#include "sysemu/cpu-throttle.h"
#include "rdma.h"
#include "ram.h"
+#include "migration/cpr.h"
#include "migration/global_state.h"
#include "migration/misc.h"
#include "migration.h"
@@ -2118,6 +2119,10 @@ void qmp_migrate(const char *uri, bool has_channels,
}
}
+ if (cpr_state_save(&local_err)) {
+ goto out;
+ }
+
if (addr->transport == MIGRATION_ADDRESS_TYPE_SOCKET) {
SocketAddress *saddr = &addr->u.socket;
if (saddr->type == SOCKET_ADDRESS_TYPE_INET ||
@@ -2142,6 +2147,7 @@ void qmp_migrate(const char *uri, bool has_channels,
MIGRATION_STATUS_FAILED);
}
+out:
if (local_err) {
if (!resume_requested) {
yank_unregister_instance(MIGRATION_YANK_INSTANCE);
@@ -340,6 +340,11 @@ colo_receive_message(const char *msg) "Receive '%s' message"
# colo-failover.c
colo_failover_set_state(const char *new_state) "new state %s"
+# cpr.c
+cpr_save_fd(const char *name, int id, int fd) "%s, id %d, fd %d"
+cpr_delete_fd(const char *name, int id) "%s, id %d"
+cpr_find_fd(const char *name, int id, int fd) "%s, id %d returns %d"
+
# block-dirty-bitmap.c
send_bitmap_header_enter(void) ""
send_bitmap_bits(uint32_t flags, uint64_t start_sector, uint32_t nr_sectors, uint64_t data_size) "flags: 0x%x, start_sector: %" PRIu64 ", nr_sectors: %" PRIu32 ", data_size: %" PRIu64
@@ -77,6 +77,7 @@
#include "hw/block/block.h"
#include "hw/i386/x86.h"
#include "hw/i386/pc.h"
+#include "migration/cpr.h"
#include "migration/misc.h"
#include "migration/snapshot.h"
#include "sysemu/tpm.h"
@@ -3713,6 +3714,8 @@ void qemu_init(int argc, char **argv)
qemu_create_machine(machine_opts_dict);
+ cpr_state_load(&error_fatal);
+
suspend_mux_open();
qemu_disable_default_devices();
CPR must save state that is needed after QEMU is restarted, when devices are realized. Thus the extra state cannot be saved in the migration stream, as objects must already exist before that stream can be loaded. Instead, define auxilliary state structures and vmstate descriptions, not associated with any registered object, and serialize the aux state to a cpr-specific stream in cpr_state_save. Deserialize in cpr_state_load after QEMU restarts, before devices are realized. Provide accessors for clients to register file descriptors for saving. The mechanism for passing the fd's to the new process will be specific to each migration mode, and added in subsequent patches. Signed-off-by: Steve Sistare <steven.sistare@oracle.com> --- include/migration/cpr.h | 21 ++++++ migration/cpr.c | 188 ++++++++++++++++++++++++++++++++++++++++++++++++ migration/meson.build | 1 + migration/migration.c | 6 ++ migration/trace-events | 5 ++ system/vl.c | 3 + 6 files changed, 224 insertions(+) create mode 100644 include/migration/cpr.h create mode 100644 migration/cpr.c