[lxc-devel] [PATCH 1/2] c/r: move criu code to its own file
Tycho Andersen
tycho.andersen at canonical.com
Thu Apr 16 18:40:56 UTC 2015
Trying to cage the beast that is lxccontainer.c.
Signed-off-by: Tycho Andersen <tycho.andersen at canonical.com>
---
src/lxc/Makefile.am | 4 +-
src/lxc/criu.c | 477 +++++++++++++++++++++++++++++++++++++++++++++++++
src/lxc/criu.h | 70 ++++++++
src/lxc/lxccontainer.c | 454 +---------------------------------------------
4 files changed, 551 insertions(+), 454 deletions(-)
create mode 100644 src/lxc/criu.c
create mode 100644 src/lxc/criu.h
diff --git a/src/lxc/Makefile.am b/src/lxc/Makefile.am
index d8e460b..2731843 100644
--- a/src/lxc/Makefile.am
+++ b/src/lxc/Makefile.am
@@ -21,7 +21,8 @@ noinst_HEADERS = \
namespace.h \
start.h \
state.h \
- utils.h
+ utils.h \
+ criu.h
if IS_BIONIC
noinst_HEADERS += \
@@ -75,6 +76,7 @@ liblxc_so_SOURCES = \
state.c state.h \
log.c log.h \
attach.c attach.h \
+ criu.c criu.h \
\
network.c network.h \
nl.c nl.h \
diff --git a/src/lxc/criu.c b/src/lxc/criu.c
new file mode 100644
index 0000000..043db36
--- /dev/null
+++ b/src/lxc/criu.c
@@ -0,0 +1,477 @@
+/*
+ * lxc: linux Container library
+ *
+ * Copyright © 2014-2015 Canonical Ltd.
+ *
+ * Authors:
+ * Tycho Andersen <tycho.andersen at canonical.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#define _GNU_SOURCE
+#include <assert.h>
+#include <linux/limits.h>
+#include <sched.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mount.h>
+#include <sys/types.h>
+#include <sys/wait.h>
+#include <unistd.h>
+
+#include "config.h"
+
+#include "bdev.h"
+#include "cgroup.h"
+#include "conf.h"
+#include "criu.h"
+#include "log.h"
+#include "lxc.h"
+#include "lxclock.h"
+#include "network.h"
+#include "utils.h"
+
+lxc_log_define(lxc_criu, lxc);
+
+void exec_criu(struct criu_opts *opts)
+{
+ char **argv, log[PATH_MAX];
+ int static_args = 18, argc = 0, i, ret;
+ int netnr = 0;
+ struct lxc_list *it;
+
+ char buf[4096];
+ FILE *mnts = NULL;
+
+ /* The command line always looks like:
+ * criu $(action) --tcp-established --file-locks --link-remap --force-irmap \
+ * --manage-cgroups action-script foo.sh -D $(directory) \
+ * -o $(directory)/$(action).log --ext-mount-map auto
+ * --enable-external-sharing --enable-external-masters
+ * +1 for final NULL */
+
+ if (strcmp(opts->action, "dump") == 0) {
+ /* -t pid */
+ static_args += 2;
+
+ /* --leave-running */
+ if (!opts->stop)
+ static_args++;
+ } else if (strcmp(opts->action, "restore") == 0) {
+ /* --root $(lxc_mount_point) --restore-detached
+ * --restore-sibling --pidfile $foo --cgroup-root $foo */
+ static_args += 8;
+ } else {
+ return;
+ }
+
+ if (opts->verbose)
+ static_args++;
+
+ ret = snprintf(log, PATH_MAX, "%s/%s.log", opts->directory, opts->action);
+ if (ret < 0 || ret >= PATH_MAX) {
+ ERROR("logfile name too long\n");
+ return;
+ }
+
+ argv = malloc(static_args * sizeof(*argv));
+ if (!argv)
+ return;
+
+ memset(argv, 0, static_args * sizeof(*argv));
+
+#define DECLARE_ARG(arg) \
+ do { \
+ if (arg == NULL) { \
+ ERROR("Got NULL argument for criu"); \
+ goto err; \
+ } \
+ argv[argc++] = strdup(arg); \
+ if (!argv[argc-1]) \
+ goto err; \
+ } while (0)
+
+ argv[argc++] = on_path("criu", NULL);
+ if (!argv[argc-1]) {
+ ERROR("Couldn't find criu binary\n");
+ goto err;
+ }
+
+ DECLARE_ARG(opts->action);
+ DECLARE_ARG("--tcp-established");
+ DECLARE_ARG("--file-locks");
+ DECLARE_ARG("--link-remap");
+ DECLARE_ARG("--force-irmap");
+ DECLARE_ARG("--manage-cgroups");
+ DECLARE_ARG("--ext-mount-map");
+ DECLARE_ARG("auto");
+ DECLARE_ARG("--enable-external-sharing");
+ DECLARE_ARG("--enable-external-masters");
+ DECLARE_ARG("-D");
+ DECLARE_ARG(opts->directory);
+ DECLARE_ARG("-o");
+ DECLARE_ARG(log);
+
+ if (opts->verbose)
+ DECLARE_ARG("-vvvvvv");
+
+ if (strcmp(opts->action, "dump") == 0) {
+ char pid[32];
+
+ if (sprintf(pid, "%d", opts->c->init_pid(opts->c)) < 0)
+ goto err;
+
+ DECLARE_ARG("-t");
+ DECLARE_ARG(pid);
+ if (!opts->stop)
+ DECLARE_ARG("--leave-running");
+ } else if (strcmp(opts->action, "restore") == 0) {
+ void *m;
+ int additional;
+
+ DECLARE_ARG("--root");
+ DECLARE_ARG(opts->c->lxc_conf->rootfs.mount);
+ DECLARE_ARG("--restore-detached");
+ DECLARE_ARG("--restore-sibling");
+ DECLARE_ARG("--pidfile");
+ DECLARE_ARG(opts->pidfile);
+ DECLARE_ARG("--cgroup-root");
+ DECLARE_ARG(opts->cgroup_path);
+
+ additional = lxc_list_len(&opts->c->lxc_conf->network) * 2;
+
+ m = realloc(argv, (argc + additional + 1) * sizeof(*argv)); \
+ if (!m) \
+ goto err; \
+ argv = m;
+
+ lxc_list_for_each(it, &opts->c->lxc_conf->network) {
+ char eth[128], *veth;
+ struct lxc_netdev *n = it->elem;
+
+ if (n->name) {
+ if (strlen(n->name) >= sizeof(eth))
+ goto err;
+ strncpy(eth, n->name, sizeof(eth));
+ } else
+ sprintf(eth, "eth%d", netnr);
+
+ veth = n->priv.veth_attr.pair;
+
+ ret = snprintf(buf, sizeof(buf), "%s=%s@%s", eth, veth, n->link);
+ if (ret < 0 || ret >= sizeof(buf))
+ goto err;
+
+ DECLARE_ARG("--veth-pair");
+ DECLARE_ARG(buf);
+ }
+
+ }
+
+ argv[argc] = NULL;
+
+#undef DECLARE_ARG
+ execv(argv[0], argv);
+err:
+ if (mnts)
+ fclose(mnts);
+ for (i = 0; argv[i]; i++)
+ free(argv[i]);
+ free(argv);
+}
+
+/* Check and make sure the container has a configuration that we know CRIU can
+ * dump. */
+bool criu_ok(struct lxc_container *c)
+{
+ struct lxc_list *it;
+ bool found_deny_rule = false;
+
+ if (geteuid()) {
+ ERROR("Must be root to checkpoint\n");
+ return false;
+ }
+
+ /* We only know how to restore containers with veth networks. */
+ lxc_list_for_each(it, &c->lxc_conf->network) {
+ struct lxc_netdev *n = it->elem;
+ if (n->type != LXC_NET_VETH && n->type != LXC_NET_NONE) {
+ ERROR("Found network that is not VETH or NONE\n");
+ return false;
+ }
+ }
+
+ // These requirements come from http://criu.org/LXC
+ if (c->lxc_conf->console.path &&
+ strcmp(c->lxc_conf->console.path, "none") != 0) {
+ ERROR("lxc.console must be none\n");
+ return false;
+ }
+
+ if (c->lxc_conf->tty != 0) {
+ ERROR("lxc.tty must be 0\n");
+ return false;
+ }
+
+ lxc_list_for_each(it, &c->lxc_conf->cgroup) {
+ struct lxc_cgroup *cg = it->elem;
+ if (strcmp(cg->subsystem, "devices.deny") == 0 &&
+ strcmp(cg->value, "c 5:1 rwm") == 0) {
+
+ found_deny_rule = true;
+ break;
+ }
+ }
+
+ if (!found_deny_rule) {
+ ERROR("couldn't find devices.deny = c 5:1 rwm");
+ return false;
+ }
+
+ return true;
+}
+
+bool dump_net_info(struct lxc_container *c, char *directory)
+{
+ int netnr;
+ struct lxc_list *it;
+
+ netnr = 0;
+ lxc_list_for_each(it, &c->lxc_conf->network) {
+ char *veth = NULL, *bridge = NULL, veth_path[PATH_MAX], eth[128];
+ struct lxc_netdev *n = it->elem;
+ bool has_error = true;
+ int pret;
+
+ pret = snprintf(veth_path, PATH_MAX, "lxc.network.%d.veth.pair", netnr);
+ if (pret < 0 || pret >= PATH_MAX)
+ goto out;
+
+ veth = c->get_running_config_item(c, veth_path);
+ if (!veth) {
+ /* criu_ok() checks that all interfaces are
+ * LXC_NET{VETH,NONE}, and VETHs should have this
+ * config */
+ assert(n->type == LXC_NET_NONE);
+ break;
+ }
+
+ bridge = c->get_running_config_item(c, veth_path);
+ if (!bridge)
+ goto out;
+
+ pret = snprintf(veth_path, PATH_MAX, "%s/veth%d", directory, netnr);
+ if (pret < 0 || pret >= PATH_MAX || print_to_file(veth_path, veth) < 0)
+ goto out;
+
+ if (n->name) {
+ if (strlen(n->name) >= 128)
+ goto out;
+ strncpy(eth, n->name, 128);
+ } else
+ sprintf(eth, "eth%d", netnr);
+
+ has_error = false;
+out:
+ free(veth);
+ free(bridge);
+ if (has_error)
+ return false;
+ }
+
+ return true;
+}
+
+static bool restore_net_info(struct lxc_container *c)
+{
+ struct lxc_list *it;
+ bool has_error = true;
+
+ if (container_mem_lock(c))
+ return false;
+
+ lxc_list_for_each(it, &c->lxc_conf->network) {
+ struct lxc_netdev *netdev = it->elem;
+ char template[IFNAMSIZ];
+ snprintf(template, sizeof(template), "vethXXXXXX");
+
+ if (!netdev->priv.veth_attr.pair)
+ netdev->priv.veth_attr.pair = lxc_mkifname(template);
+
+ if (!netdev->priv.veth_attr.pair)
+ goto out_unlock;
+ }
+
+ has_error = false;
+
+out_unlock:
+ container_mem_unlock(c);
+ return !has_error;
+}
+
+void do_restore(struct lxc_container *c, int pipe, char *directory, bool verbose)
+{
+ pid_t pid;
+ char pidfile[L_tmpnam];
+ struct lxc_handler *handler;
+ int status;
+
+ if (!tmpnam(pidfile))
+ goto out;
+
+ handler = lxc_init(c->name, c->lxc_conf, c->config_path);
+ if (!handler)
+ goto out;
+
+ if (!cgroup_init(handler)) {
+ ERROR("failed initing cgroups");
+ goto out_fini_handler;
+ }
+
+ if (!cgroup_create(handler)) {
+ ERROR("failed creating groups");
+ goto out_fini_handler;
+ }
+
+ if (!restore_net_info(c)) {
+ ERROR("failed restoring network info");
+ goto out_fini_handler;
+ }
+
+ resolve_clone_flags(handler);
+
+ pid = fork();
+ if (pid < 0)
+ goto out_fini_handler;
+
+ if (pid == 0) {
+ struct criu_opts os;
+ struct lxc_rootfs *rootfs;
+
+ close(pipe);
+ pipe = -1;
+
+ if (unshare(CLONE_NEWNS))
+ goto out_fini_handler;
+
+ /* CRIU needs the lxc root bind mounted so that it is the root of some
+ * mount. */
+ rootfs = &c->lxc_conf->rootfs;
+
+ if (rootfs_is_blockdev(c->lxc_conf)) {
+ if (do_rootfs_setup(c->lxc_conf, c->name, c->config_path) < 0)
+ goto out_fini_handler;
+ } else {
+ if (mkdir(rootfs->mount, 0755) < 0 && errno != EEXIST)
+ goto out_fini_handler;
+
+ if (mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL) < 0) {
+ SYSERROR("remount / to private failed");
+ goto out_fini_handler;
+ }
+
+ if (mount(rootfs->path, rootfs->mount, NULL, MS_BIND, NULL) < 0) {
+ rmdir(rootfs->mount);
+ goto out_fini_handler;
+ }
+ }
+
+ os.action = "restore";
+ os.directory = directory;
+ os.c = c;
+ os.pidfile = pidfile;
+ os.verbose = verbose;
+ os.cgroup_path = cgroup_canonical_path(handler);
+
+ /* exec_criu() returning is an error */
+ exec_criu(&os);
+ umount(rootfs->mount);
+ rmdir(rootfs->mount);
+ goto out_fini_handler;
+ } else {
+ int ret;
+ char title[2048];
+
+ pid_t w = waitpid(pid, &status, 0);
+ if (w == -1) {
+ SYSERROR("waitpid");
+ goto out_fini_handler;
+ }
+
+ ret = write(pipe, &status, sizeof(status));
+ close(pipe);
+ pipe = -1;
+
+ if (sizeof(status) != ret) {
+ SYSERROR("failed to write all of status");
+ goto out_fini_handler;
+ }
+
+ if (WIFEXITED(status)) {
+ if (WEXITSTATUS(status)) {
+ goto out_fini_handler;
+ } else {
+ int ret;
+ FILE *f = fopen(pidfile, "r");
+ if (!f) {
+ SYSERROR("couldn't read restore's init pidfile %s\n", pidfile);
+ goto out_fini_handler;
+ }
+
+ ret = fscanf(f, "%d", (int*) &handler->pid);
+ fclose(f);
+ if (ret != 1) {
+ ERROR("reading restore pid failed");
+ goto out_fini_handler;
+ }
+
+ if (lxc_set_state(c->name, handler, RUNNING))
+ goto out_fini_handler;
+ }
+ } else {
+ ERROR("CRIU was killed with signal %d\n", WTERMSIG(status));
+ goto out_fini_handler;
+ }
+
+ /*
+ * See comment in lxcapi_start; we don't care if these
+ * fail because it's just a beauty thing. We just
+ * assign the return here to silence potential.
+ */
+ ret = snprintf(title, sizeof(title), "[lxc monitor] %s %s", c->config_path, c->name);
+ ret = setproctitle(title);
+
+ ret = lxc_poll(c->name, handler);
+ if (ret)
+ lxc_abort(c->name, handler);
+ lxc_fini(c->name, handler);
+ exit(ret);
+ }
+
+out_fini_handler:
+ lxc_fini(c->name, handler);
+
+out:
+ if (pipe >= 0) {
+ status = 1;
+ if (write(pipe, &status, sizeof(status)) != sizeof(status)) {
+ SYSERROR("writing status failed");
+ }
+ close(pipe);
+ }
+
+ exit(1);
+}
diff --git a/src/lxc/criu.h b/src/lxc/criu.h
new file mode 100644
index 0000000..1f65e47
--- /dev/null
+++ b/src/lxc/criu.h
@@ -0,0 +1,70 @@
+/*
+ * lxc: linux Container library
+ *
+ * Copyright © 2014-2015 Canonical Ltd.
+ *
+ * Authors:
+ * Tycho Andersen <tycho.andersen at canonical.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+#ifndef __LXC_CRIU_H
+#define __LXC_CRIU_H
+
+#include <stdbool.h>
+
+#include <lxc/lxccontainer.h>
+
+// We require either the criu major/minor version, or the criu GITID if criu
+// was built from git.
+#define CRIU_VERSION "1.6"
+
+#define CRIU_GITID_VERSION "1.5"
+#define CRIU_GITID_PATCHLEVEL 133
+
+struct criu_opts {
+ /* The type of criu invocation, one of "dump" or "restore" */
+ char *action;
+
+ /* The directory to pass to criu */
+ char *directory;
+
+ /* The container to dump */
+ struct lxc_container *c;
+
+ /* Enable criu verbose mode? */
+ bool verbose;
+
+ /* dump: stop the container or not after dumping? */
+ bool stop;
+
+ /* restore: the file to write the init process' pid into */
+ char *pidfile;
+ const char *cgroup_path;
+};
+
+void exec_criu(struct criu_opts *opts);
+
+/* Check and make sure the container has a configuration that we know CRIU can
+ * dump. */
+bool criu_ok(struct lxc_container *c);
+
+bool dump_net_info(struct lxc_container *c, char *directory);
+
+// do_restore never returns, the calling process is used as the
+// monitor process. do_restore calls exit() if it fails.
+void do_restore(struct lxc_container *c, int pipe, char *directory, bool verbose);
+
+#endif
diff --git a/src/lxc/lxccontainer.c b/src/lxc/lxccontainer.c
index d6826ab..0ca5b9f 100644
--- a/src/lxc/lxccontainer.c
+++ b/src/lxc/lxccontainer.c
@@ -50,6 +50,7 @@
#include "console.h"
#include "cgroup.h"
#include "commands.h"
+#include "criu.h"
#include "log.h"
#include "bdev.h"
#include "utils.h"
@@ -3496,276 +3497,6 @@ static bool lxcapi_detach_interface(struct lxc_container *c, const char *ifname,
return true;
}
-struct criu_opts {
- /* The type of criu invocation, one of "dump" or "restore" */
- char *action;
-
- /* The directory to pass to criu */
- char *directory;
-
- /* The container to dump */
- struct lxc_container *c;
-
- /* Enable criu verbose mode? */
- bool verbose;
-
- /* dump: stop the container or not after dumping? */
- bool stop;
-
- /* restore: the file to write the init process' pid into */
- char *pidfile;
- const char *cgroup_path;
-};
-
-static void exec_criu(struct criu_opts *opts)
-{
- char **argv, log[PATH_MAX];
- int static_args = 18, argc = 0, i, ret;
- int netnr = 0;
- struct lxc_list *it;
-
- char buf[4096];
- FILE *mnts = NULL;
-
- /* The command line always looks like:
- * criu $(action) --tcp-established --file-locks --link-remap --force-irmap \
- * --manage-cgroups action-script foo.sh -D $(directory) \
- * -o $(directory)/$(action).log --ext-mount-map auto
- * --enable-external-sharing --enable-external-masters
- * +1 for final NULL */
-
- if (strcmp(opts->action, "dump") == 0) {
- /* -t pid */
- static_args += 2;
-
- /* --leave-running */
- if (!opts->stop)
- static_args++;
- } else if (strcmp(opts->action, "restore") == 0) {
- /* --root $(lxc_mount_point) --restore-detached
- * --restore-sibling --pidfile $foo --cgroup-root $foo */
- static_args += 8;
- } else {
- return;
- }
-
- if (opts->verbose)
- static_args++;
-
- ret = snprintf(log, PATH_MAX, "%s/%s.log", opts->directory, opts->action);
- if (ret < 0 || ret >= PATH_MAX) {
- ERROR("logfile name too long\n");
- return;
- }
-
- argv = malloc(static_args * sizeof(*argv));
- if (!argv)
- return;
-
- memset(argv, 0, static_args * sizeof(*argv));
-
-#define DECLARE_ARG(arg) \
- do { \
- if (arg == NULL) { \
- ERROR("Got NULL argument for criu"); \
- goto err; \
- } \
- argv[argc++] = strdup(arg); \
- if (!argv[argc-1]) \
- goto err; \
- } while (0)
-
- argv[argc++] = on_path("criu", NULL);
- if (!argv[argc-1]) {
- ERROR("Couldn't find criu binary\n");
- goto err;
- }
-
- DECLARE_ARG(opts->action);
- DECLARE_ARG("--tcp-established");
- DECLARE_ARG("--file-locks");
- DECLARE_ARG("--link-remap");
- DECLARE_ARG("--force-irmap");
- DECLARE_ARG("--manage-cgroups");
- DECLARE_ARG("--ext-mount-map");
- DECLARE_ARG("auto");
- DECLARE_ARG("--enable-external-sharing");
- DECLARE_ARG("--enable-external-masters");
- DECLARE_ARG("-D");
- DECLARE_ARG(opts->directory);
- DECLARE_ARG("-o");
- DECLARE_ARG(log);
-
- if (opts->verbose)
- DECLARE_ARG("-vvvvvv");
-
- if (strcmp(opts->action, "dump") == 0) {
- char pid[32];
-
- if (sprintf(pid, "%d", lxcapi_init_pid(opts->c)) < 0)
- goto err;
-
- DECLARE_ARG("-t");
- DECLARE_ARG(pid);
- if (!opts->stop)
- DECLARE_ARG("--leave-running");
- } else if (strcmp(opts->action, "restore") == 0) {
- void *m;
- int additional;
-
- DECLARE_ARG("--root");
- DECLARE_ARG(opts->c->lxc_conf->rootfs.mount);
- DECLARE_ARG("--restore-detached");
- DECLARE_ARG("--restore-sibling");
- DECLARE_ARG("--pidfile");
- DECLARE_ARG(opts->pidfile);
- DECLARE_ARG("--cgroup-root");
- DECLARE_ARG(opts->cgroup_path);
-
- additional = lxc_list_len(&opts->c->lxc_conf->network) * 2;
-
- m = realloc(argv, (argc + additional + 1) * sizeof(*argv)); \
- if (!m) \
- goto err; \
- argv = m;
-
- lxc_list_for_each(it, &opts->c->lxc_conf->network) {
- char eth[128], *veth;
- struct lxc_netdev *n = it->elem;
-
- if (n->name) {
- if (strlen(n->name) >= sizeof(eth))
- goto err;
- strncpy(eth, n->name, sizeof(eth));
- } else
- sprintf(eth, "eth%d", netnr);
-
- veth = n->priv.veth_attr.pair;
-
- ret = snprintf(buf, sizeof(buf), "%s=%s@%s", eth, veth, n->link);
- if (ret < 0 || ret >= sizeof(buf))
- goto err;
-
- DECLARE_ARG("--veth-pair");
- DECLARE_ARG(buf);
- }
-
- }
-
- argv[argc] = NULL;
-
-#undef DECLARE_ARG
- execv(argv[0], argv);
-err:
- if (mnts)
- fclose(mnts);
- for (i = 0; argv[i]; i++)
- free(argv[i]);
- free(argv);
-}
-
-/* Check and make sure the container has a configuration that we know CRIU can
- * dump. */
-static bool criu_ok(struct lxc_container *c)
-{
- struct lxc_list *it;
- bool found_deny_rule = false;
-
- if (geteuid()) {
- ERROR("Must be root to checkpoint\n");
- return false;
- }
-
- /* We only know how to restore containers with veth networks. */
- lxc_list_for_each(it, &c->lxc_conf->network) {
- struct lxc_netdev *n = it->elem;
- if (n->type != LXC_NET_VETH && n->type != LXC_NET_NONE) {
- ERROR("Found network that is not VETH or NONE\n");
- return false;
- }
- }
-
- // These requirements come from http://criu.org/LXC
- if (c->lxc_conf->console.path &&
- strcmp(c->lxc_conf->console.path, "none") != 0) {
- ERROR("lxc.console must be none\n");
- return false;
- }
-
- if (c->lxc_conf->tty != 0) {
- ERROR("lxc.tty must be 0\n");
- return false;
- }
-
- lxc_list_for_each(it, &c->lxc_conf->cgroup) {
- struct lxc_cgroup *cg = it->elem;
- if (strcmp(cg->subsystem, "devices.deny") == 0 &&
- strcmp(cg->value, "c 5:1 rwm") == 0) {
-
- found_deny_rule = true;
- break;
- }
- }
-
- if (!found_deny_rule) {
- ERROR("couldn't find devices.deny = c 5:1 rwm");
- return false;
- }
-
- return true;
-}
-
-static bool dump_net_info(struct lxc_container *c, char *directory)
-{
- int netnr;
- struct lxc_list *it;
-
- netnr = 0;
- lxc_list_for_each(it, &c->lxc_conf->network) {
- char *veth = NULL, *bridge = NULL, veth_path[PATH_MAX], eth[128];
- struct lxc_netdev *n = it->elem;
- bool has_error = true;
- int pret;
-
- pret = snprintf(veth_path, PATH_MAX, "lxc.network.%d.veth.pair", netnr);
- if (pret < 0 || pret >= PATH_MAX)
- goto out;
-
- veth = lxcapi_get_running_config_item(c, veth_path);
- if (!veth) {
- /* criu_ok() checks that all interfaces are
- * LXC_NET{VETH,NONE}, and VETHs should have this
- * config */
- assert(n->type == LXC_NET_NONE);
- break;
- }
-
- bridge = lxcapi_get_running_config_item(c, veth_path);
- if (!bridge)
- goto out;
-
- pret = snprintf(veth_path, PATH_MAX, "%s/veth%d", directory, netnr);
- if (pret < 0 || pret >= PATH_MAX || print_to_file(veth_path, veth) < 0)
- goto out;
-
- if (n->name) {
- if (strlen(n->name) >= 128)
- goto out;
- strncpy(eth, n->name, 128);
- } else
- sprintf(eth, "eth%d", netnr);
-
- has_error = false;
-out:
- free(veth);
- free(bridge);
- if (has_error)
- return false;
- }
-
- return true;
-}
-
static bool lxcapi_checkpoint(struct lxc_container *c, char *directory, bool stop, bool verbose)
{
pid_t pid;
@@ -3811,189 +3542,6 @@ static bool lxcapi_checkpoint(struct lxc_container *c, char *directory, bool sto
}
}
-static bool restore_net_info(struct lxc_container *c)
-{
- struct lxc_list *it;
- bool has_error = true;
-
- if (container_mem_lock(c))
- return false;
-
- lxc_list_for_each(it, &c->lxc_conf->network) {
- struct lxc_netdev *netdev = it->elem;
- char template[IFNAMSIZ];
- snprintf(template, sizeof(template), "vethXXXXXX");
-
- if (!netdev->priv.veth_attr.pair)
- netdev->priv.veth_attr.pair = lxc_mkifname(template);
-
- if (!netdev->priv.veth_attr.pair)
- goto out_unlock;
- }
-
- has_error = false;
-
-out_unlock:
- container_mem_unlock(c);
- return !has_error;
-}
-
-// do_restore never returns, the calling process is used as the
-// monitor process. do_restore calls exit() if it fails.
-static void do_restore(struct lxc_container *c, int pipe, char *directory, bool verbose)
-{
- pid_t pid;
- char pidfile[L_tmpnam];
- struct lxc_handler *handler;
- int status;
-
- if (!tmpnam(pidfile))
- goto out;
-
- handler = lxc_init(c->name, c->lxc_conf, c->config_path);
- if (!handler)
- goto out;
-
- if (!cgroup_init(handler)) {
- ERROR("failed initing cgroups");
- goto out_fini_handler;
- }
-
- if (!cgroup_create(handler)) {
- ERROR("failed creating groups");
- goto out_fini_handler;
- }
-
- if (!restore_net_info(c)) {
- ERROR("failed restoring network info");
- goto out_fini_handler;
- }
-
- resolve_clone_flags(handler);
-
- pid = fork();
- if (pid < 0)
- goto out_fini_handler;
-
- if (pid == 0) {
- struct criu_opts os;
- struct lxc_rootfs *rootfs;
-
- close(pipe);
- pipe = -1;
-
- if (unshare(CLONE_NEWNS))
- goto out_fini_handler;
-
- /* CRIU needs the lxc root bind mounted so that it is the root of some
- * mount. */
- rootfs = &c->lxc_conf->rootfs;
-
- if (rootfs_is_blockdev(c->lxc_conf)) {
- if (do_rootfs_setup(c->lxc_conf, c->name, c->config_path) < 0)
- goto out_fini_handler;
- } else {
- if (mkdir(rootfs->mount, 0755) < 0 && errno != EEXIST)
- goto out_fini_handler;
-
- if (mount(NULL, "/", NULL, MS_SLAVE | MS_REC, NULL) < 0) {
- SYSERROR("remount / to private failed");
- goto out_fini_handler;
- }
-
- if (mount(rootfs->path, rootfs->mount, NULL, MS_BIND, NULL) < 0) {
- rmdir(rootfs->mount);
- goto out_fini_handler;
- }
- }
-
- os.action = "restore";
- os.directory = directory;
- os.c = c;
- os.pidfile = pidfile;
- os.verbose = verbose;
- os.cgroup_path = cgroup_canonical_path(handler);
-
- /* exec_criu() returning is an error */
- exec_criu(&os);
- umount(rootfs->mount);
- rmdir(rootfs->mount);
- goto out_fini_handler;
- } else {
- int ret;
- char title[2048];
-
- pid_t w = waitpid(pid, &status, 0);
- if (w == -1) {
- SYSERROR("waitpid");
- goto out_fini_handler;
- }
-
- ret = write(pipe, &status, sizeof(status));
- close(pipe);
- pipe = -1;
-
- if (sizeof(status) != ret) {
- SYSERROR("failed to write all of status");
- goto out_fini_handler;
- }
-
- if (WIFEXITED(status)) {
- if (WEXITSTATUS(status)) {
- goto out_fini_handler;
- } else {
- int ret;
- FILE *f = fopen(pidfile, "r");
- if (!f) {
- SYSERROR("couldn't read restore's init pidfile %s\n", pidfile);
- goto out_fini_handler;
- }
-
- ret = fscanf(f, "%d", (int*) &handler->pid);
- fclose(f);
- if (ret != 1) {
- ERROR("reading restore pid failed");
- goto out_fini_handler;
- }
-
- if (lxc_set_state(c->name, handler, RUNNING))
- goto out_fini_handler;
- }
- } else {
- ERROR("CRIU was killed with signal %d\n", WTERMSIG(status));
- goto out_fini_handler;
- }
-
- /*
- * See comment in lxcapi_start; we don't care if these
- * fail because it's just a beauty thing. We just
- * assign the return here to silence potential.
- */
- ret = snprintf(title, sizeof(title), "[lxc monitor] %s %s", c->config_path, c->name);
- ret = setproctitle(title);
-
- ret = lxc_poll(c->name, handler);
- if (ret)
- lxc_abort(c->name, handler);
- lxc_fini(c->name, handler);
- exit(ret);
- }
-
-out_fini_handler:
- lxc_fini(c->name, handler);
-
-out:
- if (pipe >= 0) {
- status = 1;
- if (write(pipe, &status, sizeof(status)) != sizeof(status)) {
- SYSERROR("writing status failed");
- }
- close(pipe);
- }
-
- exit(1);
-}
-
static bool lxcapi_restore(struct lxc_container *c, char *directory, bool verbose)
{
pid_t pid;
--
2.1.4
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