[PATCH RFC 3/3] lxc: Adding support to LXC driver to restore a container
Julio Faracco
jcfaracco at gmail.com
Sat Feb 27 04:06:35 UTC 2021
This patch introduces the hability to restore a saved container using CRIU.
It should be possible to start it using traditional methods: a simple container
start; or from a saved state.
Signed-off-by: Julio Faracco <jcfaracco at gmail.com>
---
src/lxc/lxc_conf.c | 3 +
src/lxc/lxc_conf.h | 2 +
src/lxc/lxc_container.c | 188 ++++++++++++++++++++-
src/lxc/lxc_container.h | 3 +-
src/lxc/lxc_controller.c | 93 ++++++++++-
src/lxc/lxc_driver.c | 341 ++++++++++++++++++++++++++++++++++++++-
src/lxc/lxc_process.c | 26 ++-
src/lxc/lxc_process.h | 1 +
8 files changed, 638 insertions(+), 19 deletions(-)
diff --git a/src/lxc/lxc_conf.c b/src/lxc/lxc_conf.c
index e6ad91205e..690cef7d39 100644
--- a/src/lxc/lxc_conf.c
+++ b/src/lxc/lxc_conf.c
@@ -240,6 +240,8 @@ virLXCDriverConfigNew(void)
cfg->logDir = g_strdup(LXC_LOG_DIR);
cfg->autostartDir = g_strdup(LXC_AUTOSTART_DIR);
+ cfg->saveImageFormat = NULL;
+
return cfg;
}
@@ -291,4 +293,5 @@ virLXCDriverConfigDispose(void *obj)
g_free(cfg->stateDir);
g_free(cfg->logDir);
g_free(cfg->securityDriverName);
+ g_free(cfg->saveImageFormat);
}
diff --git a/src/lxc/lxc_conf.h b/src/lxc/lxc_conf.h
index 664bafc7b9..08bea11c02 100644
--- a/src/lxc/lxc_conf.h
+++ b/src/lxc/lxc_conf.h
@@ -61,6 +61,8 @@ struct _virLXCDriverConfig {
char *securityDriverName;
bool securityDefaultConfined;
bool securityRequireConfined;
+
+ char *saveImageFormat;
};
struct _virLXCDriver {
diff --git a/src/lxc/lxc_container.c b/src/lxc/lxc_container.c
index 2a5f8711c4..03c086d029 100644
--- a/src/lxc/lxc_container.c
+++ b/src/lxc/lxc_container.c
@@ -51,6 +51,7 @@
#include "virerror.h"
#include "virlog.h"
#include "lxc_container.h"
+#include "lxc_criu.h"
#include "viralloc.h"
#include "virnetdevveth.h"
#include "viruuid.h"
@@ -84,6 +85,7 @@ struct __lxc_child_argv {
char **ttyPaths;
int handshakefd;
int *nsInheritFDs;
+ int restorefd;
};
static int lxcContainerMountFSBlock(virDomainFSDefPtr fs,
@@ -235,8 +237,8 @@ static virCommandPtr lxcContainerBuildInitCmd(virDomainDefPtr vmDef,
*
* Returns 0 on success or -1 in case of error
*/
-static int lxcContainerSetupFDs(int *ttyfd,
- size_t npassFDs, int *passFDs)
+static int lxcContainerSetupFDs(int *ttyfd, size_t npassFDs,
+ int *passFDs, int restorefd)
{
int rc = -1;
int open_max;
@@ -335,6 +337,10 @@ static int lxcContainerSetupFDs(int *ttyfd,
for (fd = last_fd + 1; fd < open_max; fd++) {
int tmpfd = fd;
+
+ if (tmpfd == restorefd)
+ continue;
+
VIR_MASS_CLOSE(tmpfd);
}
@@ -1017,6 +1023,30 @@ static int lxcContainerMountFSDevPTS(virDomainDefPtr def,
return 0;
}
+
+static int lxcContainerMountFSDevPTSRestore(virDomainDefPtr def,
+ const char *stateDir)
+{
+ int flags = MS_MOVE;
+ g_autofree char *path = NULL;
+
+ VIR_DEBUG("Mount /dev/pts stateDir=%s", stateDir);
+
+ path = g_strdup_printf("%s/%s.devpts", stateDir, def->name);
+
+ VIR_DEBUG("Trying to move %s to /dev/pts", path);
+
+ if (mount(path, "/dev/pts", NULL, flags, NULL) < 0) {
+ virReportSystemError(errno,
+ _("Failed to mount %s on /dev/pts"),
+ path);
+ return -1;
+ }
+
+ return 0;
+}
+
+
static int lxcContainerSetupDevices(char **ttyPaths, size_t nttyPaths)
{
size_t i;
@@ -1843,6 +1873,139 @@ static int lxcAttachNS(int *ns_fd)
return 0;
}
+
+/*
+ * lxcContainerChildRestore:
+ * @data: pointer to container arguments
+ */
+static int lxcContainerChildRestore(void *data)
+{
+ lxc_child_argv_t *argv = data;
+ virDomainDefPtr vmDef = argv->config;
+ int ttyfd = -1;
+ int ret = -1;
+ virDomainFSDefPtr root;
+ g_autofree char *ttyPath = NULL;
+ g_autofree char *sec_mount_options = NULL;
+ g_autofree char *stateDir = NULL;
+ g_autofree char *rootfs_mount = NULL;
+
+ if (NULL == vmDef) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ "%s", _("lxcChild() passed invalid vm definition"));
+ goto cleanup;
+ }
+
+ if (lxcContainerWaitForContinue(argv->monitor) < 0) {
+ virReportSystemError(errno, "%s",
+ _("Failed to read the container continue message"));
+ goto cleanup;
+ }
+ VIR_DEBUG("Received container continue message");
+
+ if (lxcContainerSetID(vmDef) < 0)
+ goto cleanup;
+
+ root = virDomainGetFilesystemForTarget(vmDef, "/");
+
+ if (argv->nttyPaths) {
+ const char *tty = argv->ttyPaths[0];
+
+ if (STRPREFIX(tty, "/dev/pts/"))
+ tty += strlen("/dev/pts/");
+
+ ttyPath = g_strdup_printf("%s/%s.devpts/%s",
+ LXC_STATE_DIR, vmDef->name, tty);
+ } else {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("At least one tty is required"));
+ goto cleanup;
+ }
+
+ VIR_DEBUG("Container TTY path: %s", ttyPath);
+
+ ttyfd = open(ttyPath, O_RDWR);
+ if (ttyfd < 0) {
+ virReportSystemError(errno,
+ _("Failed to open tty %s"),
+ ttyPath);
+ goto cleanup;
+ }
+ VIR_DEBUG("Container TTY fd: %d", ttyfd);
+
+ if (!(sec_mount_options = virSecurityManagerGetMountOptions(
+ argv->securityDriver,
+ vmDef)))
+ goto cleanup;
+
+ if (lxcContainerPrepareRoot(vmDef, root, sec_mount_options) < 0)
+ goto cleanup;
+
+ if (lxcContainerSendContinue(argv->handshakefd) < 0) {
+ virReportSystemError(errno, "%s",
+ _("Failed to send continue signal to controller"));
+ goto cleanup;
+ }
+
+ VIR_DEBUG("Setting up container's std streams");
+
+ if (lxcContainerSetupFDs(&ttyfd,
+ argv->npassFDs, argv->passFDs, argv->restorefd) < 0)
+ goto cleanup;
+
+ /* CRIU needs the container's root bind mounted so that it is the root of
+ * some mount.
+ */
+ rootfs_mount = g_strdup_printf("%s/save/%s", LXC_STATE_DIR, vmDef->name);
+
+ if (virFileMakePath(rootfs_mount) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to mkdir rootfs mount path"));
+ goto cleanup;
+ }
+
+ if (mount(root->src->path, rootfs_mount, NULL, MS_BIND, NULL) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to create rootfs mountpoint"));
+ goto cleanup;
+ }
+
+ if (virFileResolveAllLinks(LXC_STATE_DIR, &stateDir) < 0)
+ goto cleanup;
+
+ /* Mounts /dev/pts */
+ if (lxcContainerMountFSDevPTSRestore(vmDef, stateDir) < 0) {
+ virReportSystemError(errno, "%s",
+ _("Failed to mount dev/pts"));
+ goto cleanup;
+ }
+
+ if (setsid() < 0) {
+ virReportSystemError(errno, "%s",
+ _("Unable to become session leader"));
+ }
+
+ ret = 0;
+
+ cleanup:
+ VIR_FORCE_CLOSE(argv->monitor);
+ VIR_FORCE_CLOSE(argv->handshakefd);
+ VIR_FORCE_CLOSE(ttyfd);
+
+ if (ret == 0) {
+ VIR_DEBUG("Executing container restore criu function");
+ ret = lxcCriuRestore(vmDef, argv->restorefd, 0);
+ } else {
+ VIR_DEBUG("Tearing down container");
+ fprintf(stderr,
+ _("Failure in libvirt_lxc startup: %s\n"),
+ virGetLastErrorMessage());
+ }
+
+ return ret;
+}
+
+
/**
* lxcContainerSetUserGroup:
* @cmd: command to update
@@ -2049,7 +2212,7 @@ static int lxcContainerChild(void *data)
VIR_FORCE_CLOSE(argv->handshakefd);
VIR_FORCE_CLOSE(argv->monitor);
if (lxcContainerSetupFDs(&ttyfd,
- argv->npassFDs, argv->passFDs) < 0)
+ argv->npassFDs, argv->passFDs, -1) < 0)
goto cleanup;
/* Make init process of the container the leader of the new session.
@@ -2143,7 +2306,8 @@ int lxcContainerStart(virDomainDefPtr def,
int handshakefd,
int *nsInheritFDs,
size_t nttyPaths,
- char **ttyPaths)
+ char **ttyPaths,
+ int restorefd)
{
pid_t pid;
int cflags;
@@ -2162,6 +2326,7 @@ int lxcContainerStart(virDomainDefPtr def,
.ttyPaths = ttyPaths,
.handshakefd = handshakefd,
.nsInheritFDs = nsInheritFDs,
+ .restorefd = restorefd,
};
/* allocate a stack for the container */
@@ -2207,9 +2372,18 @@ int lxcContainerStart(virDomainDefPtr def,
VIR_DEBUG("Inheriting a UTS namespace");
}
- VIR_DEBUG("Cloning container init process");
- pid = clone(lxcContainerChild, stacktop, cflags, &args);
- VIR_DEBUG("clone() completed, new container PID is %d", pid);
+ if (restorefd == -1)
+ VIR_DEBUG("Cloning container init process");
+ else
+ VIR_DEBUG("Cloning container process that will spawn criu restore");
+
+ if (restorefd != -1)
+ pid = clone(lxcContainerChildRestore, stacktop, SIGCHLD, &args);
+ else
+ pid = clone(lxcContainerChild, stacktop, cflags, &args);
+
+ if (restorefd == -1)
+ VIR_DEBUG("clone() completed, new container PID is %d", pid);
if (pid < 0) {
virReportSystemError(errno, "%s",
diff --git a/src/lxc/lxc_container.h b/src/lxc/lxc_container.h
index 94a6c5309c..cf61a033fc 100644
--- a/src/lxc/lxc_container.h
+++ b/src/lxc/lxc_container.h
@@ -54,7 +54,8 @@ int lxcContainerStart(virDomainDefPtr def,
int handshakefd,
int *nsInheritFDs,
size_t nttyPaths,
- char **ttyPaths);
+ char **ttyPaths,
+ int restorefd);
int lxcContainerSetupHostdevCapsMakePath(const char *dev);
diff --git a/src/lxc/lxc_controller.c b/src/lxc/lxc_controller.c
index 8f166a436a..5bd0712ba9 100644
--- a/src/lxc/lxc_controller.c
+++ b/src/lxc/lxc_controller.c
@@ -139,6 +139,8 @@ struct _virLXCController {
virCgroupPtr cgroup;
virLXCFusePtr fuse;
+
+ int restore;
};
#include "lxc_controller_dispatch.h"
@@ -1006,6 +1008,54 @@ static int lxcControllerClearCapabilities(void)
return 0;
}
+
+static int lxcControllerFindRestoredPid(int fd)
+{
+ int initpid = 0;
+ int ret = -1;
+ g_autofree char *checkpointdir = NULL;
+ g_autofree char *pidfile = NULL;
+ g_autofree char *checkpointfd = NULL;
+ int pidfilefd;
+ char c;
+
+ if (fd < 0)
+ goto cleanup;
+
+ checkpointfd = g_strdup_printf("/proc/self/fd/%d", fd);
+
+ if (virFileResolveLink(checkpointfd, &checkpointdir) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to readlink checkpoint dir path"));
+ goto cleanup;
+ }
+
+ pidfile = g_strdup_printf("%s/restore.pid", checkpointdir);
+
+ if ((pidfilefd = virFileOpenAs(pidfile, O_RDONLY, 0, -1, -1, 0)) < 0) {
+ virReportSystemError(pidfilefd,
+ _("Failed to open domain's pidfile '%s'"),
+ pidfile);
+ goto cleanup;
+ }
+
+ while ((saferead(pidfilefd, &c, 1) == 1) && c != EOF)
+ initpid = initpid*10 + c - '0';
+
+ ret = initpid;
+
+ if (virFileRemove(pidfile, -1, -1) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to delete pidfile path"));
+ }
+
+ cleanup:
+ VIR_FORCE_CLOSE(fd);
+ VIR_FORCE_CLOSE(pidfilefd);
+ return ret;
+}
+
+
static bool wantReboot;
static virMutex lock = VIR_MUTEX_INITIALIZER;
@@ -2310,6 +2360,7 @@ virLXCControllerRun(virLXCControllerPtr ctrl)
int rc = -1;
int control[2] = { -1, -1};
int containerhandshake[2] = { -1, -1 };
+ bool restore_mode = (ctrl->restore != -1);
char **containerTTYPaths = g_new0(char *, ctrl->nconsoles);
size_t i;
@@ -2368,7 +2419,8 @@ virLXCControllerRun(virLXCControllerPtr ctrl)
containerhandshake[1],
ctrl->nsFDs,
ctrl->nconsoles,
- containerTTYPaths)) < 0)
+ containerTTYPaths,
+ ctrl->restore)) < 0)
goto cleanup;
VIR_FORCE_CLOSE(control[1]);
VIR_FORCE_CLOSE(containerhandshake[1]);
@@ -2380,10 +2432,10 @@ virLXCControllerRun(virLXCControllerPtr ctrl)
for (i = 0; i < VIR_LXC_DOMAIN_NAMESPACE_LAST; i++)
VIR_FORCE_CLOSE(ctrl->nsFDs[i]);
- if (virLXCControllerSetupCgroupLimits(ctrl) < 0)
+ if (!restore_mode && virLXCControllerSetupCgroupLimits(ctrl) < 0)
goto cleanup;
- if (virLXCControllerSetupUserns(ctrl) < 0)
+ if (!restore_mode && virLXCControllerSetupUserns(ctrl) < 0)
goto cleanup;
if (virLXCControllerMoveInterfaces(ctrl) < 0)
@@ -2408,6 +2460,26 @@ virLXCControllerRun(virLXCControllerPtr ctrl)
if (lxcControllerClearCapabilities() < 0)
goto cleanup;
+ if (restore_mode) {
+ int status;
+ int ret = waitpid(-1, &status, 0);
+ int initpid;
+
+ VIR_DEBUG("Got sig child %d", ret);
+
+ /* We have two basic cases here.
+ * - CRIU died bacause of restore error and we do not have a running container
+ * - CRIU detached itself from the running container
+ */
+ if ((initpid = lxcControllerFindRestoredPid(ctrl->restore)) < 0) {
+ virReportSystemError(errno, "%s",
+ _("Unable to get restored task pid"));
+ virNetDaemonQuit(ctrl->daemon);
+ goto cleanup;
+ }
+ ctrl->initpid = initpid;
+ }
+
for (i = 0; i < ctrl->nconsoles; i++)
if (virLXCControllerConsoleSetNonblocking(&(ctrl->consoles[i])) < 0)
goto cleanup;
@@ -2450,6 +2522,7 @@ int main(int argc, char *argv[])
char **veths = NULL;
int ns_fd[VIR_LXC_DOMAIN_NAMESPACE_LAST];
int handshakeFd = -1;
+ int restore = -1;
bool bg = false;
const struct option options[] = {
{ "background", 0, NULL, 'b' },
@@ -2462,6 +2535,7 @@ int main(int argc, char *argv[])
{ "share-net", 1, NULL, 'N' },
{ "share-ipc", 1, NULL, 'I' },
{ "share-uts", 1, NULL, 'U' },
+ { "restore", 1, NULL, 'r' },
{ "help", 0, NULL, 'h' },
{ 0, 0, 0, 0 },
};
@@ -2488,7 +2562,7 @@ int main(int argc, char *argv[])
while (1) {
int c;
- c = getopt_long(argc, argv, "dn:v:p:m:c:s:h:S:N:I:U:",
+ c = getopt_long(argc, argv, "dn:v:p:m:c:s:h:S:N:I:U:r:",
options, NULL);
if (c == -1)
@@ -2560,6 +2634,14 @@ int main(int argc, char *argv[])
securityDriver = optarg;
break;
+ case 'r':
+ if (virStrToLong_i(optarg, NULL, 10, &restore) < 0) {
+ fprintf(stderr, "malformed --restore argument '%s'",
+ optarg);
+ goto cleanup;
+ }
+ break;
+
case 'h':
case '?':
fprintf(stderr, "\n");
@@ -2576,6 +2658,7 @@ int main(int argc, char *argv[])
fprintf(stderr, " -N FD, --share-net FD\n");
fprintf(stderr, " -I FD, --share-ipc FD\n");
fprintf(stderr, " -U FD, --share-uts FD\n");
+ fprintf(stderr, " -r FD, --restore FD\n");
fprintf(stderr, " -h, --help\n");
fprintf(stderr, "\n");
rc = 0;
@@ -2628,6 +2711,8 @@ int main(int argc, char *argv[])
ctrl->passFDs = passFDs;
ctrl->npassFDs = npassFDs;
+ ctrl->restore = restore;
+
for (i = 0; i < VIR_LXC_DOMAIN_NAMESPACE_LAST; i++) {
if (ns_fd[i] != -1) {
if (!ctrl->nsFDs) {/*allocate only once */
diff --git a/src/lxc/lxc_driver.c b/src/lxc/lxc_driver.c
index 4416acf923..44306685f5 100644
--- a/src/lxc/lxc_driver.c
+++ b/src/lxc/lxc_driver.c
@@ -44,6 +44,7 @@
#include "lxc_driver.h"
#include "lxc_native.h"
#include "lxc_process.h"
+#include "lxc_criu.h"
#include "virnetdevbridge.h"
#include "virnetdevveth.h"
#include "virnetdevopenvswitch.h"
@@ -1012,7 +1013,7 @@ static int lxcDomainCreateWithFiles(virDomainPtr dom,
ret = virLXCProcessStart(dom->conn, driver, vm,
nfiles, files,
(flags & VIR_DOMAIN_START_AUTODESTROY),
- VIR_DOMAIN_RUNNING_BOOTED);
+ -1, VIR_DOMAIN_RUNNING_BOOTED);
if (ret == 0) {
event = virDomainEventLifecycleNewFromObj(vm,
@@ -1135,7 +1136,7 @@ lxcDomainCreateXMLWithFiles(virConnectPtr conn,
if (virLXCProcessStart(conn, driver, vm,
nfiles, files,
(flags & VIR_DOMAIN_START_AUTODESTROY),
- VIR_DOMAIN_RUNNING_BOOTED) < 0) {
+ -1, VIR_DOMAIN_RUNNING_BOOTED) < 0) {
virDomainAuditStart(vm, "booted", false);
virLXCDomainObjEndJob(driver, vm);
if (!vm->persistent)
@@ -2731,6 +2732,338 @@ static int lxcDomainResume(virDomainPtr dom)
return ret;
}
+
+static int
+lxcDoDomainSave(virLXCDriverPtr driver, virDomainObjPtr vm,
+ const char *to)
+{
+ virCapsPtr caps = NULL;
+ virLXCSaveHeader hdr;
+ virLXCDriverConfigPtr cfg = virLXCDriverGetConfig(driver);
+ g_autofree char *checkpointdir = NULL;
+ g_autofree char *criufile = NULL;
+ g_autofree char *xml = NULL;
+ uint32_t xml_len;
+ int compressed = 0;
+ int fd = -1;
+ int criufd = -1;
+ int ret = -1;
+ ssize_t r;
+
+ if (!(caps = virLXCDriverGetCapabilities(driver, false)))
+ return -1;
+
+ checkpointdir = g_path_get_dirname(to);
+
+ if (lxcCriuDump(vm, checkpointdir) != 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to checkpoint domain with CRIU"));
+ goto cleanup;
+ }
+
+ if ((compressed = lxcCriuCompress(checkpointdir,
+ cfg->saveImageFormat)) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to compress criu files"));
+ goto cleanup;
+ }
+
+ hdr.compressed = compressed;
+
+ if ((fd = virFileOpenAs(to, O_CREAT | O_TRUNC | O_WRONLY,
+ S_IRUSR | S_IWUSR, -1, -1, 0)) < 0) {
+ virReportSystemError(-fd,
+ _("Failed to create domain save file '%s'"), to);
+ goto cleanup;
+ }
+
+ if ((xml = virDomainDefFormat(vm->def, driver->xmlopt, 0)) == NULL)
+ goto cleanup;
+
+ xml_len = strlen(xml) + 1;
+
+ memset(&hdr, 0, sizeof(hdr));
+ memcpy(hdr.magic, LXC_SAVE_MAGIC, sizeof(hdr.magic));
+ hdr.version = LXC_SAVE_VERSION;
+ hdr.xmlLen = xml_len;
+
+ if (safewrite(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("Failed to write save file header"));
+ goto cleanup;
+ }
+
+ if (safewrite(fd, xml, xml_len) != xml_len) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("Failed to write xml description"));
+ goto cleanup;
+ }
+
+ criufile = g_strdup_printf("%s/criu.save", checkpointdir);
+ if ((criufd = virFileOpenAs(criufile, O_RDONLY,
+ 0, -1, -1, 0)) < 0) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("Failed to read criu file"));
+ goto cleanup;
+ }
+
+ do {
+ char buf[1024];
+
+ if ((r = saferead(criufd, buf, sizeof(buf))) < 0) {
+ virReportSystemError(errno,
+ _("Unable to read from file '%s'"),
+ criufile);
+ goto cleanup;
+ }
+
+ if (safewrite(fd, buf, r) < 0) {
+ virReportSystemError(errno,
+ _("Unable to write to file '%s'"),
+ to);
+ goto cleanup;
+ }
+ } while (r);
+
+ if (virFileRemove(criufile, -1, -1) < 0)
+ VIR_WARN("failed to remove scratch file '%s'",
+ criufile);
+
+ virDomainObjSetState(vm, VIR_DOMAIN_SHUTOFF,
+ VIR_DOMAIN_SHUTOFF_SAVED);
+
+ ret = 0;
+ cleanup:
+ VIR_FORCE_CLOSE(fd);
+ VIR_FORCE_CLOSE(criufd);
+ virObjectUnref(caps);
+ virObjectUnref(cfg);
+ return ret;
+}
+
+static int
+lxcDomainSaveFlags(virDomainPtr dom, const char *to, const char *dxml,
+ unsigned int flags)
+{
+ int ret = -1;
+ virLXCDriverPtr driver = dom->conn->privateData;
+ virDomainObjPtr vm;
+ bool remove_dom = false;
+
+ virCheckFlags(0, -1);
+ if (dxml) {
+ virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+ _("xml modification unsupported"));
+ return -1;
+ }
+
+ if (!(vm = lxcDomObjFromDomain(dom)))
+ goto cleanup;
+
+ if (virDomainSaveFlagsEnsureACL(dom->conn, vm->def) < 0)
+ goto cleanup;
+
+ if (virLXCDomainObjBeginJob(driver, vm, LXC_JOB_MODIFY) < 0)
+ goto cleanup;
+
+ if (!virDomainObjIsActive(vm)) {
+ virReportError(VIR_ERR_OPERATION_INVALID, "%s",
+ _("Domain is not running"));
+ goto endjob;
+ }
+
+ if (lxcDoDomainSave(driver, vm, to) < 0)
+ goto endjob;
+
+ if (!vm->persistent)
+ remove_dom = true;
+
+ ret = 0;
+
+ endjob:
+ virLXCDomainObjEndJob(driver, vm);
+
+ cleanup:
+ if (remove_dom && vm)
+ virDomainObjListRemove(driver->domains, vm);
+ virDomainObjEndAPI(&vm);
+ return ret;
+}
+
+static int
+lxcDomainSave(virDomainPtr dom, const char *to)
+{
+ return lxcDomainSaveFlags(dom, to, NULL, 0);
+}
+
+static int
+lxcDomainRestoreFlags(virConnectPtr conn, const char *from,
+ const char* dxml, unsigned int flags)
+{
+ virLXCDriverPtr driver = conn->privateData;
+ virLXCDriverConfigPtr cfg = NULL;
+ virLXCSaveHeader hdr;
+ virDomainObjPtr vm = NULL;
+ virDomainDefPtr def = NULL;
+ virCapsPtr caps = NULL;
+ int ret = -1;
+ int restorefd;
+ g_autofree char *xml = NULL;
+ g_autofree char *xml_image_path = NULL;
+ g_autofree char *criufile = NULL;
+ g_autofree char *savedir = NULL;
+ g_autofree char *checkpointdir = NULL;
+ ssize_t r;
+ int criufd;
+ int fd;
+
+ virCheckFlags(0, -1);
+ if (dxml) {
+ virReportError(VIR_ERR_ARGUMENT_UNSUPPORTED, "%s",
+ _("xml modification unsupported"));
+ goto out;
+ }
+
+ if ((fd = virFileOpenAs(from, O_RDONLY, 0, -1, -1, 0)) < 0) {
+ virReportSystemError(-fd,
+ _("Failed to open domain image file '%s'"),
+ xml_image_path);
+ goto out;
+ }
+
+ if (saferead(fd, &hdr, sizeof(hdr)) != sizeof(hdr)) {
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ "%s", _("failed to read lxc header"));
+ return -1;
+ }
+
+ if (memcmp(hdr.magic, LXC_SAVE_MAGIC, sizeof(hdr.magic)) != 0) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("image magic is incorrect"));
+ return -1;
+ }
+
+ if (hdr.version > LXC_SAVE_VERSION) {
+ virReportError(VIR_ERR_OPERATION_FAILED,
+ _("image version is not supported (%d > %d)"),
+ hdr.version, LXC_SAVE_VERSION);
+ return -1;
+ }
+
+ cfg = virLXCDriverGetConfig(driver);
+
+ xml = g_new0(char, hdr.xmlLen);
+
+ if (saferead(fd, xml, hdr.xmlLen) != hdr.xmlLen) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s", _("failed to read XML"));
+ goto cleanup;
+ }
+
+ checkpointdir = g_path_get_dirname(from);
+
+ criufile = g_strdup_printf("%s/criu.save", checkpointdir);
+ if ((criufd = virFileOpenAs(criufile, O_CREAT | O_TRUNC | O_WRONLY,
+ S_IRUSR | S_IWUSR, -1, -1, 0)) < 0) {
+ virReportError(VIR_ERR_OPERATION_FAILED, "%s",
+ _("Failed to read criu file"));
+ goto cleanup;
+ }
+
+ do {
+ char buf[1024];
+
+ if ((r = saferead(fd, buf, sizeof(buf))) < 0) {
+ virReportSystemError(errno,
+ _("Unable to read from file '%s'"),
+ criufile);
+ goto cleanup;
+ }
+
+ if (safewrite(criufd, buf, r) < 0) {
+ virReportSystemError(errno,
+ _("Unable to write to file '%s'"),
+ from);
+ goto cleanup;
+ }
+ } while (r);
+
+ if (lxcCriuDecompress(checkpointdir,
+ cfg->saveImageFormat) < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("Failed to decompress criu files"));
+ goto cleanup;
+ }
+
+ if (!xml) {
+ virReportError(VIR_ERR_INTERNAL_ERROR, "%s",
+ _("no domain XML parsed"));
+ goto cleanup;
+ }
+
+ if (!(caps = virLXCDriverGetCapabilities(driver, false)))
+ goto cleanup;
+
+ if (!(def = virDomainDefParseString(xml, driver->xmlopt, caps,
+ VIR_DOMAIN_DEF_PARSE_INACTIVE)))
+ goto cleanup;
+
+ if (virDomainRestoreFlagsEnsureACL(conn, def) < 0)
+ goto cleanup;
+
+ if (!(vm = virDomainObjListAdd(driver->domains, def,
+ driver->xmlopt,
+ VIR_DOMAIN_OBJ_LIST_ADD_LIVE |
+ VIR_DOMAIN_OBJ_LIST_ADD_CHECK_LIVE,
+ NULL)))
+ goto cleanup;
+ def = NULL;
+
+ if (virLXCDomainObjBeginJob(driver, vm, LXC_JOB_MODIFY) < 0) {
+ if (!vm->persistent)
+ virDomainObjListRemove(driver->domains, vm);
+ goto cleanup;
+ }
+
+ savedir = g_strdup_printf("%s/save/", checkpointdir);
+
+ restorefd = open(savedir, O_DIRECTORY);
+ if (restorefd < 0) {
+ virReportError(VIR_ERR_INTERNAL_ERROR,
+ "%s", _("Can't open images dir"));
+ if (!vm->persistent)
+ virDomainObjListRemove(driver->domains, vm);
+ virLXCDomainObjEndJob(driver, vm);
+ goto cleanup;
+ }
+
+ ret = virLXCProcessStart(conn, driver, vm,
+ 0, NULL,
+ 0, restorefd,
+ VIR_DOMAIN_RUNNING_RESTORED);
+
+ VIR_FORCE_CLOSE(restorefd);
+
+ if (ret < 0 && !vm->persistent)
+ virDomainObjListRemove(driver->domains, vm);
+
+ virLXCDomainObjEndJob(driver, vm);
+ cleanup:
+ VIR_FORCE_CLOSE(fd);
+ VIR_FORCE_CLOSE(criufd);
+ out:
+ virDomainDefFree(def);
+ virDomainObjEndAPI(&vm);
+ virObjectUnref(cfg);
+ return ret;
+}
+
+static int
+lxcDomainRestore(virConnectPtr conn, const char *from)
+{
+ return lxcDomainRestoreFlags(conn, from, NULL, 0);
+}
+
+
static int
lxcDomainOpenConsole(virDomainPtr dom,
const char *dev_name,
@@ -5088,6 +5421,10 @@ static virHypervisorDriver lxcHypervisorDriver = {
.domainLookupByName = lxcDomainLookupByName, /* 0.4.2 */
.domainSuspend = lxcDomainSuspend, /* 0.7.2 */
.domainResume = lxcDomainResume, /* 0.7.2 */
+ .domainSave = lxcDomainSave, /* x.x.x */
+ .domainSaveFlags = lxcDomainSaveFlags, /* x.x.x */
+ .domainRestore = lxcDomainRestore, /* x.x.x */
+ .domainRestoreFlags = lxcDomainRestoreFlags, /* x.x.x */
.domainDestroy = lxcDomainDestroy, /* 0.4.4 */
.domainDestroyFlags = lxcDomainDestroyFlags, /* 0.9.4 */
.domainGetOSType = lxcDomainGetOSType, /* 0.4.2 */
diff --git a/src/lxc/lxc_process.c b/src/lxc/lxc_process.c
index cbc04a3dcd..8dc8c42558 100644
--- a/src/lxc/lxc_process.c
+++ b/src/lxc/lxc_process.c
@@ -117,8 +117,8 @@ virLXCProcessReboot(virLXCDriverPtr driver,
vm->newDef = NULL;
virLXCProcessStop(driver, vm, VIR_DOMAIN_SHUTOFF_SHUTDOWN);
vm->newDef = savedDef;
- if (virLXCProcessStart(conn, driver, vm,
- 0, NULL, autodestroy, reason) < 0) {
+ if (virLXCProcessStart(conn, driver, vm, 0,
+ NULL, autodestroy, -1, reason) < 0) {
VIR_WARN("Unable to handle reboot of vm %s",
vm->def->name);
goto cleanup;
@@ -942,7 +942,8 @@ virLXCProcessBuildControllerCmd(virLXCDriverPtr driver,
size_t nfiles,
int handshakefd,
int * const logfd,
- const char *pidfile)
+ const char *pidfile,
+ int restorefd)
{
size_t i;
g_autofree char *filterstr = NULL;
@@ -1016,6 +1017,12 @@ virLXCProcessBuildControllerCmd(virLXCDriverPtr driver,
for (i = 0; veths && veths[i]; i++)
virCommandAddArgList(cmd, "--veth", veths[i], NULL);
+ if (restorefd != -1) {
+ virCommandAddArg(cmd, "--restore");
+ virCommandAddArgFormat(cmd, "%d", restorefd);
+ virCommandPassFD(cmd, restorefd, 0);
+ }
+
virCommandPassFD(cmd, handshakefd, 0);
virCommandDaemonize(cmd);
virCommandSetPidFile(cmd, pidfile);
@@ -1186,6 +1193,8 @@ virLXCProcessEnsureRootFS(virDomainObjPtr vm)
* @driver: pointer to driver structure
* @vm: pointer to virtual machine structure
* @autoDestroy: mark the domain for auto destruction
+ * @restorefd: file descriptor pointing to the restore directory (-1 if not
+ * restoring)
* @reason: reason for switching vm to running state
*
* Starts a vm
@@ -1197,6 +1206,7 @@ int virLXCProcessStart(virConnectPtr conn,
virDomainObjPtr vm,
unsigned int nfiles, int *files,
bool autoDestroy,
+ int restorefd,
virDomainRunningReason reason)
{
int rc = -1, r;
@@ -1388,7 +1398,8 @@ int virLXCProcessStart(virConnectPtr conn,
files, nfiles,
handshakefds[1],
&logfd,
- pidfile)))
+ pidfile,
+ restorefd)))
goto cleanup;
/* now that we know it is about to start call the hook if present */
@@ -1491,6 +1502,9 @@ int virLXCProcessStart(virConnectPtr conn,
if (!priv->machineName)
goto cleanup;
+ if (restorefd != -1)
+ goto skip_cgroup_checks;
+
/* We know the cgroup must exist by this synchronization
* point so lets detect that first, since it gives us a
* more reliable way to kill everything off if something
@@ -1507,6 +1521,8 @@ int virLXCProcessStart(virConnectPtr conn,
goto cleanup;
}
+ skip_cgroup_checks:
+
/* And we can get the first monitor connection now too */
if (!(priv->monitor = virLXCProcessConnectMonitor(driver, vm))) {
/* Intentionally overwrite the real monitor error message,
@@ -1587,7 +1603,7 @@ virLXCProcessAutostartDomain(virDomainObjPtr vm,
if (vm->autostart &&
!virDomainObjIsActive(vm)) {
ret = virLXCProcessStart(data->conn, data->driver, vm,
- 0, NULL, false,
+ 0, NULL, false, -1,
VIR_DOMAIN_RUNNING_BOOTED);
virDomainAuditStart(vm, "booted", ret >= 0);
if (ret < 0) {
diff --git a/src/lxc/lxc_process.h b/src/lxc/lxc_process.h
index 383f6f714d..dab300784f 100644
--- a/src/lxc/lxc_process.h
+++ b/src/lxc/lxc_process.h
@@ -28,6 +28,7 @@ int virLXCProcessStart(virConnectPtr conn,
virDomainObjPtr vm,
unsigned int nfiles, int *files,
bool autoDestroy,
+ int restorefd,
virDomainRunningReason reason);
int virLXCProcessStop(virLXCDriverPtr driver,
virDomainObjPtr vm,
--
2.27.0
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