The branch main has been updated by rew:
URL:
https://cgit.FreeBSD.org/src/commit/?id=edfb339d3868bbd36393efb2738287e170767784
commit edfb339d3868bbd36393efb2738287e170767784
Author: Robert Wing <r...@freebsd.org>
AuthorDate: 2022-02-09 17:11:57 +0000
Commit: Robert Wing <r...@freebsd.org>
CommitDate: 2022-02-09 17:11:57 +0000
bhyve/snapshot: switch to nvlist for snapshot requests
Switch to using an nvlist with nvlist_send()/nvlist_recv() to
communicate from bhyvectl(8) to bhyve(8).
The idea is that a bhyve process receives a command with with a set of
arguments. The nvlist here is structured to reflect that premise.
For example, to snapshot the vm, the expected nvlist looks like:
{ cmd=START_CHECKPOINT, filename="filename" }
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D33977
---
usr.sbin/bhyve/snapshot.c | 42 +++++++++++++++++++++---------------------
usr.sbin/bhyve/snapshot.h | 19 -------------------
usr.sbin/bhyvectl/Makefile | 1 +
usr.sbin/bhyvectl/bhyvectl.c | 39 +++++++++++++++++++--------------------
4 files changed, 41 insertions(+), 60 deletions(-)
diff --git a/usr.sbin/bhyve/snapshot.c b/usr.sbin/bhyve/snapshot.c
index 4c2cbed2c143..66f05ed68bcd 100644
--- a/usr.sbin/bhyve/snapshot.c
+++ b/usr.sbin/bhyve/snapshot.c
@@ -1325,7 +1325,7 @@ vm_vcpu_resume(struct vmctx *ctx)
}
static int
-vm_checkpoint(struct vmctx *ctx, char *checkpoint_file, bool stop_vm)
+vm_checkpoint(struct vmctx *ctx, const char *checkpoint_file, bool stop_vm)
{
int fd_checkpoint = 0, kdata_fd = 0;
int ret = 0;
@@ -1440,17 +1440,23 @@ done:
return (error);
}
-int
-handle_message(struct ipc_message *imsg, struct vmctx *ctx)
+static int
+handle_message(struct vmctx *ctx, nvlist_t *nvl)
{
- int err;
+ int err, cmd;
- switch (imsg->code) {
- case START_CHECKPOINT:
- err = vm_checkpoint(ctx,
imsg->data.op.snapshot_filename, false);
- break;
+ if (!nvlist_exists_number(nvl, "cmd"))
+ return (-1);
+
+ cmd = nvlist_get_number(nvl, "cmd");
+ switch (cmd) {
case START_SUSPEND:
- err = vm_checkpoint(ctx,
imsg->data.op.snapshot_filename, true);
+ case START_CHECKPOINT:
+ if (!nvlist_exists_string(nvl, "filename"))
+ err = -1;
+ else
+ err = vm_checkpoint(ctx, nvlist_get_string(nvl,
"filename"),
+ cmd == START_SUSPEND ? true : false);
break;
default:
EPRINTLN("Unrecognized checkpoint operation\n");
@@ -1460,6 +1466,7 @@ handle_message(struct ipc_message *imsg, struct vmctx
*ctx)
if (err != 0)
EPRINTLN("Unable to perform the requested operation\n");
+ nvlist_destroy(nvl);
return (err);
}
@@ -1469,25 +1476,18 @@ handle_message(struct ipc_message *imsg, struct vmctx
*ctx)
void *
checkpoint_thread(void *param)
{
- struct ipc_message imsg;
struct checkpoint_thread_info *thread_info;
- ssize_t n;
+ nvlist_t *nvl;
pthread_set_name_np(pthread_self(), "checkpoint thread");
thread_info = (struct checkpoint_thread_info *)param;
for (;;) {
- n = recvfrom(thread_info->socket_fd, &imsg, sizeof(imsg), 0,
NULL, 0);
-
- /*
- * slight sanity check: see if there's enough data to at
- * least determine the type of message.
- */
- if (n >= sizeof(imsg.code))
- handle_message(&imsg, thread_info->ctx);
+ nvl = nvlist_recv(thread_info->socket_fd, 0);
+ if (nvl != NULL)
+ handle_message(thread_info->ctx, nvl);
else
- EPRINTLN("Failed to receive message: %s\n",
- n == -1 ? strerror(errno) : "unknown error");
+ EPRINTLN("nvlist_recv() failed: %s", strerror(errno));
}
return (NULL);
diff --git a/usr.sbin/bhyve/snapshot.h b/usr.sbin/bhyve/snapshot.h
index 3ffd42fbeabc..ddf23b8c0619 100644
--- a/usr.sbin/bhyve/snapshot.h
+++ b/usr.sbin/bhyve/snapshot.h
@@ -60,31 +60,12 @@ struct restore_state {
ucl_object_t *meta_root_obj;
};
-/* Filename that will be used for save/restore */
-struct checkpoint_op {
- char snapshot_filename[MAX_SNAPSHOT_FILENAME];
-};
-
/* Messages that a bhyve process understands. */
enum ipc_opcode {
START_CHECKPOINT,
START_SUSPEND,
};
-/*
- * The type of message and associated data to
- * send to a bhyve process.
- */
-struct ipc_message {
- enum ipc_opcode code;
- union {
- /*
- * message specific structures
- */
- struct checkpoint_op op;
- } data;
-};
-
struct checkpoint_thread_info {
struct vmctx *ctx;
int socket_fd;
diff --git a/usr.sbin/bhyvectl/Makefile b/usr.sbin/bhyvectl/Makefile
index 12fdb706cadb..c004d603c8db 100644
--- a/usr.sbin/bhyvectl/Makefile
+++ b/usr.sbin/bhyvectl/Makefile
@@ -17,6 +17,7 @@ WARNS?= 3
CFLAGS+= -I${SRCTOP}/sys/amd64/vmm
.if ${MK_BHYVE_SNAPSHOT} != "no"
+LIBADD+= nv
CFLAGS+= -DBHYVE_SNAPSHOT
# usr.sbin/bhyve/snapshot.h needs ucl header
diff --git a/usr.sbin/bhyvectl/bhyvectl.c b/usr.sbin/bhyvectl/bhyvectl.c
index 017427db4d4f..560a3a3eb443 100644
--- a/usr.sbin/bhyvectl/bhyvectl.c
+++ b/usr.sbin/bhyvectl/bhyvectl.c
@@ -33,10 +33,13 @@ __FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/types.h>
-#include <sys/sysctl.h>
+#include <sys/cpuset.h>
#include <sys/errno.h>
#include <sys/mman.h>
-#include <sys/cpuset.h>
+#include <sys/nv.h>
+#include <sys/socket.h>
+#include <sys/sysctl.h>
+#include <sys/un.h>
#include <stdio.h>
#include <stdlib.h>
@@ -57,9 +60,6 @@ __FBSDID("$FreeBSD$");
#include <machine/vmm_dev.h>
#include <vmmapi.h>
-#include <sys/socket.h>
-#include <sys/un.h>
-
#include "amd/vmcb.h"
#include "intel/vmcs.h"
@@ -1684,10 +1684,9 @@ show_memseg(struct vmctx *ctx)
#ifdef BHYVE_SNAPSHOT
static int
-send_message(struct vmctx *ctx, void *data, size_t len)
+send_message(struct vmctx *ctx, nvlist_t *nvl)
{
struct sockaddr_un addr;
- ssize_t len_sent;
int err, socket_fd;
char vmname_buf[MAX_VMNAME];
@@ -1709,14 +1708,16 @@ send_message(struct vmctx *ctx, void *data, size_t len)
snprintf(addr.sun_path, sizeof(addr.sun_path), "%s%s", BHYVE_RUN_DIR,
vmname_buf);
- len_sent = sendto(socket_fd, data, len, 0,
- (struct sockaddr *)&addr, sizeof(struct sockaddr_un));
-
- if (len_sent < 0) {
- perror("Failed to send message to bhyve vm");
- err = -1;
+ if (connect(socket_fd, (struct sockaddr *)&addr, SUN_LEN(&addr)) != 0) {
+ perror("connect() failed");
+ err = errno;
+ goto done;
}
+ if (nvlist_send(socket_fd, nvl) < 0)
+ perror("nvlist_send() failed");
+ nvlist_destroy(nvl);
+
done:
if (socket_fd > 0)
close(socket_fd);
@@ -1726,15 +1727,13 @@ done:
static int
snapshot_request(struct vmctx *ctx, const char *file, enum ipc_opcode code)
{
- struct ipc_message imsg;
- size_t length;
-
- imsg.code = code;
- strlcpy(imsg.data.op.snapshot_filename, file, MAX_SNAPSHOT_FILENAME);
+ nvlist_t *nvl;
- length = offsetof(struct ipc_message, data) + sizeof(imsg.data.op);
+ nvl = nvlist_create(0);
+ nvlist_add_number(nvl, "cmd", code);
+ nvlist_add_string(nvl, "filename", file);
- return (send_message(ctx, (void *)&imsg, length));
+ return (send_message(ctx, nvl));
}
#endif
