criu/crtools.c
Deyan Doychev 69a6bf4439 criu: Add exec-cmd option (v3)
The --exec-cmd option specifies a command that will be execvp()-ed on successful
restore. This way the command specified here will become the parent process of
the restored process tree.

Waiting for the restored processes to finish is responsibility of this command.

All service FDs are closed before we call execvp(). Standad output and error of
the command are redirected to the log file when we are restoring through the RPC
service.

This option will be used when restoring LinuX Containers and it seems helpful
for perf or other use cases when restored processes must be supervised by a
parent.

Two directions were researched in order to integrate CRIU and LXC:

1. We tell to CRIU, that after restoring container is should execve()
   lxc properly explaining to it that there's a new container hanging
   around.

2. We make LXC set himself as child subreaper, then fork() criu and ask
   it to detach (-d) from restore container afterwards. Being a subreaper,
   it should get the container's init into his child list after it.

The main reason for choosing the first option is that the second one can't work
with the RPC service. If we call restore via the service then criu service will
be the top-most task in the hierarchy and will not be able to reparent the
restore trees to any other task in the system. Calling execve from service
worker sub-task (and daemonizing it) should solve this.

Signed-off-by: Deyan Doychev <deyandoichev@gmail.com>
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>
2014-03-25 01:20:02 +04:00

565 lines
14 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <unistd.h>
#include <errno.h>
#include <getopt.h>
#include <string.h>
#include <ctype.h>
#include <fcntl.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <dlfcn.h>
#include "asm/types.h"
#include "compiler.h"
#include "crtools.h"
#include "cr_options.h"
#include "sockets.h"
#include "syscall.h"
#include "files.h"
#include "sk-inet.h"
#include "net.h"
#include "version.h"
#include "page-xfer.h"
#include "tty.h"
#include "file-lock.h"
#include "cr-service.h"
#include "plugin.h"
struct cr_options opts;
void init_opts(void)
{
memset(&opts, 0, sizeof(opts));
/* Default options */
opts.final_state = TASK_DEAD;
INIT_LIST_HEAD(&opts.veth_pairs);
INIT_LIST_HEAD(&opts.scripts);
opts.cpu_cap = CPU_CAP_ALL;
}
static int parse_ns_string(const char *ptr)
{
const char *end = ptr + strlen(ptr);
do {
if (ptr[3] != ',' && ptr[3] != '\0')
goto bad_ns;
if (!strncmp(ptr, "uts", 3))
opts.rst_namespaces_flags |= CLONE_NEWUTS;
else if (!strncmp(ptr, "ipc", 3))
opts.rst_namespaces_flags |= CLONE_NEWIPC;
else if (!strncmp(ptr, "mnt", 3))
opts.rst_namespaces_flags |= CLONE_NEWNS;
else if (!strncmp(ptr, "pid", 3))
opts.rst_namespaces_flags |= CLONE_NEWPID;
else if (!strncmp(ptr, "net", 3))
opts.rst_namespaces_flags |= CLONE_NEWNET;
else
goto bad_ns;
ptr += 4;
} while (ptr < end);
return 0;
bad_ns:
pr_msg("Error: unknown namespace: %s\n", ptr);
return -1;
}
static int parse_cpu_cap(struct cr_options *opts, const char *optarg)
{
bool inverse = false;
#define ____cpu_set_cap(__opts, __cap, __inverse) \
do { \
if ((__inverse)) \
(__opts)->cpu_cap &= ~(__cap); \
else \
(__opts)->cpu_cap |= (__cap); \
} while (0)
for (; *optarg; optarg++) {
if (optarg[0] == '^') {
inverse = !inverse;
continue;
} else if (optarg[0] == ',') {
inverse = false;
continue;
}
if (!strncmp(optarg, "fpu", 3))
____cpu_set_cap(opts, CPU_CAP_FPU, inverse);
if (!strncmp(optarg, "all", 3))
____cpu_set_cap(opts, CPU_CAP_ALL, inverse);
else
goto Esyntax;
}
#undef ____cpu_set_cap
return 0;
Esyntax:
pr_err("Unknown FPU mode `%s' selected\n", optarg);
return -1;
}
int main(int argc, char *argv[])
{
pid_t pid = 0, tree_id = 0;
int ret = -1;
bool usage_error = true;
bool has_exec_cmd = false;
int opt, idx;
int log_level = LOG_UNSET;
char *imgs_dir = ".";
char *work_dir = NULL;
static const char short_opts[] = "dsRf:F:t:p:hcD:o:n:v::xVr:jlW:L:";
static struct option long_opts[] = {
{ "tree", required_argument, 0, 't' },
{ "pid", required_argument, 0, 'p' },
{ "leave-stopped", no_argument, 0, 's' },
{ "leave-running", no_argument, 0, 'R' },
{ "restore-detached", no_argument, 0, 'd' },
{ "daemon", no_argument, 0, 'd' },
{ "contents", no_argument, 0, 'c' },
{ "file", required_argument, 0, 'f' },
{ "fields", required_argument, 0, 'F' },
{ "images-dir", required_argument, 0, 'D' },
{ "work-dir", required_argument, 0, 'W' },
{ "log-file", required_argument, 0, 'o' },
{ "namespaces", required_argument, 0, 'n' },
{ "root", required_argument, 0, 'r' },
{ USK_EXT_PARAM, no_argument, 0, 'x' },
{ "help", no_argument, 0, 'h' },
{ SK_EST_PARAM, no_argument, 0, 42 },
{ "close", required_argument, 0, 43 },
{ "log-pid", no_argument, 0, 44},
{ "version", no_argument, 0, 'V'},
{ "evasive-devices", no_argument, 0, 45},
{ "pidfile", required_argument, 0, 46},
{ "veth-pair", required_argument, 0, 47},
{ "action-script", required_argument, 0, 49},
{ LREMAP_PARAM, no_argument, 0, 41},
{ OPT_SHELL_JOB, no_argument, 0, 'j'},
{ OPT_FILE_LOCKS, no_argument, 0, 'l'},
{ "page-server", no_argument, 0, 50},
{ "address", required_argument, 0, 51},
{ "port", required_argument, 0, 52},
{ "prev-images-dir", required_argument, 0, 53},
{ "ms", no_argument, 0, 54},
{ "track-mem", no_argument, 0, 55},
{ "auto-dedup", no_argument, 0, 56},
{ "libdir", required_argument, 0, 'L'},
{ "cpu-cap", required_argument, 0, 57},
{ "force-irmap", no_argument, 0, 58},
{ "exec-cmd", no_argument, 0, 59},
{ },
};
BUILD_BUG_ON(PAGE_SIZE != PAGE_IMAGE_SIZE);
cr_pb_init();
restrict_uid(getuid(), getgid());
if (argc < 2)
goto usage;
init_opts();
if (init_service_fd())
return 1;
while (1) {
idx = -1;
opt = getopt_long(argc, argv, short_opts, long_opts, &idx);
if (opt == -1)
break;
switch (opt) {
case 's':
opts.final_state = TASK_STOPPED;
break;
case 'R':
opts.final_state = TASK_ALIVE;
break;
case 'x':
opts.ext_unix_sk = true;
break;
case 'p':
pid = atoi(optarg);
if (pid <= 0)
goto bad_arg;
break;
case 't':
tree_id = atoi(optarg);
if (tree_id <= 0)
goto bad_arg;
break;
case 'c':
opts.show_pages_content = true;
break;
case 'f':
opts.show_dump_file = optarg;
break;
case 'F':
opts.show_fmt = optarg;
break;
case 'r':
opts.root = optarg;
break;
case 'd':
opts.restore_detach = true;
break;
case 'D':
imgs_dir = optarg;
break;
case 'W':
work_dir = optarg;
break;
case 'o':
opts.output = optarg;
break;
case 'n':
if (parse_ns_string(optarg))
goto bad_arg;
break;
case 'v':
if (log_level == LOG_UNSET)
log_level = 0;
if (optarg) {
if (optarg[0] == 'v')
/* handle -vvvvv */
log_level += strlen(optarg) + 1;
else
log_level = atoi(optarg);
} else
log_level++;
break;
case 41:
pr_info("Will allow link remaps on FS\n");
opts.link_remap_ok = true;
break;
case 42:
pr_info("Will dump TCP connections\n");
opts.tcp_established_ok = true;
break;
case 43: {
int fd;
fd = atoi(optarg);
pr_info("Closing fd %d\n", fd);
close(fd);
break;
}
case 44:
opts.log_file_per_pid = 1;
break;
case 45:
opts.evasive_devices = true;
break;
case 46:
opts.pidfile = optarg;
break;
case 47:
{
char *aux;
aux = strchr(optarg, '=');
if (aux == NULL)
goto bad_arg;
*aux = '\0';
if (veth_pair_add(optarg, aux + 1))
return 1;
}
break;
case 49:
{
struct script *script;
script = xmalloc(sizeof(struct script));
if (script == NULL)
return 1;
script->path = optarg;
list_add(&script->node, &opts.scripts);
}
break;
case 50:
opts.use_page_server = true;
break;
case 51:
opts.addr = optarg;
break;
case 52:
opts.ps_port = htons(atoi(optarg));
if (!opts.ps_port)
goto bad_arg;
break;
case 'j':
opts.shell_job = true;
break;
case 'l':
opts.handle_file_locks = true;
break;
case 53:
opts.img_parent = optarg;
break;
case 55:
opts.track_mem = true;
break;
case 56:
opts.auto_dedup = true;
break;
case 57:
if (parse_cpu_cap(&opts, optarg))
goto usage;
break;
case 58:
opts.force_irmap = true;
break;
case 54:
opts.check_ms_kernel = true;
break;
case 'L':
opts.libdir = optarg;
break;
case 59:
has_exec_cmd = true;
break;
case 'V':
pr_msg("Version: %s\n", CRIU_VERSION);
if (strcmp(CRIU_GITID, "0"))
pr_msg("GitID: %s\n", CRIU_GITID);
return 0;
case 'h':
usage_error = false;
goto usage;
default:
goto usage;
}
}
if (work_dir == NULL)
work_dir = imgs_dir;
if (optind >= argc) {
pr_msg("Error: command is required\n");
goto usage;
}
if (has_exec_cmd) {
if (argc - optind <= 1) {
pr_msg("Error: --exec-cmd requires a command\n");
goto usage;
}
if (strcmp(argv[optind], "restore")) {
pr_msg("Error: --exec-cmd is available for the restore command only\n");
goto usage;
}
if (opts.restore_detach) {
pr_msg("Error: --restore-detached and --exec-cmd cannot be used together\n");
goto usage;
}
opts.exec_cmd = xmalloc((argc - optind) * sizeof(char *));
memcpy(opts.exec_cmd, &argv[optind + 1], (argc - optind - 1) * sizeof(char *));
opts.exec_cmd[argc - optind - 1] = NULL;
}
/* We must not open imgs dir, if service is called */
if (strcmp(argv[optind], "service")) {
ret = open_image_dir(imgs_dir);
if (ret < 0)
return 1;
}
if (chdir(work_dir)) {
pr_perror("Can't change directory to %s", work_dir);
return 1;
}
log_set_loglevel(log_level);
if (log_init(opts.output))
return 1;
if (opts.img_parent)
pr_info("Will do snapshot from %s\n", opts.img_parent);
if (!strcmp(argv[optind], "dump")) {
if (!tree_id)
goto opt_pid_missing;
return cr_dump_tasks(tree_id);
}
if (!strcmp(argv[optind], "pre-dump")) {
if (!tree_id)
goto opt_pid_missing;
return cr_pre_dump_tasks(tree_id) != 0;
}
if (!strcmp(argv[optind], "restore")) {
if (tree_id)
pr_warn("Using -t with criu restore is obsoleted\n");
ret = cr_restore_tasks();
if (ret == 0 && opts.exec_cmd) {
close_pid_proc();
execvp(opts.exec_cmd[0], opts.exec_cmd);
pr_perror("Failed to exec command %s", opts.exec_cmd[0]);
ret = 1;
}
return ret != 0;
}
if (!strcmp(argv[optind], "show"))
return cr_show(pid) != 0;
if (!strcmp(argv[optind], "check"))
return cr_check() != 0;
if (!strcmp(argv[optind], "exec")) {
if (!pid)
pid = tree_id; /* old usage */
if (!pid)
goto opt_pid_missing;
return cr_exec(pid, argv + optind + 1) != 0;
}
if (!strcmp(argv[optind], "page-server"))
return cr_page_server(opts.restore_detach) > 0 ? 0 : 1;
if (!strcmp(argv[optind], "service"))
return cr_service(opts.restore_detach);
if (!strcmp(argv[optind], "dedup"))
return cr_dedup() != 0;
pr_msg("Error: unknown command: %s\n", argv[optind]);
usage:
pr_msg("\n"
"Usage:\n"
" criu dump|pre-dump -t PID [<options>]\n"
" criu restore [<options>]\n"
" criu show (-D DIR)|(-f FILE) [<options>]\n"
" criu check [--ms]\n"
" criu exec -p PID <syscall-string>\n"
" criu page-server\n"
" criu service [<options>]\n"
" criu dedup\n"
"\n"
"Commands:\n"
" dump checkpoint a process/tree identified by pid\n"
" pre-dump pre-dump task(s) minimizing their frozen time\n"
" restore restore a process/tree\n"
" show show dump file(s) contents\n"
" check checks whether the kernel support is up-to-date\n"
" exec execute a system call by other task\n"
" page-server launch page server\n"
" service launch service\n"
" dedup remove duplicates in memory dump\n"
);
if (usage_error) {
pr_msg("\nTry -h|--help for more info\n");
return 1;
}
pr_msg("\n"
"Dump/Restore options:\n"
"\n"
"* Generic:\n"
" -t|--tree PID checkpoint a process tree identified by PID\n"
" -d|--restore-detached detach after restore\n"
" -s|--leave-stopped leave tasks in stopped state after checkpoint\n"
" -R|--leave-running leave tasks in running state after checkpoint\n"
" -D|--images-dir DIR directory for image files\n"
" --pidfile FILE write root task, service or page-server pid to FILE\n"
" -W|--work-dir DIR directory to cd and write logs/pidfiles/stats to\n"
" (if not specified, value of --images-dir is used)\n"
" --cpu-cap CAP require certain cpu capability. CAP: may be one of:\n"
" 'fpu','all'. To disable capability, prefix it with '^'.\n"
" --exec-cmd execute the command specified after '--' on successful\n"
" restore making it the parent of the restored process\n"
"\n"
"* Special resources support:\n"
" -x|--" USK_EXT_PARAM " allow external unix connections\n"
" --" SK_EST_PARAM " checkpoint/restore established TCP connections\n"
" -r|--root PATH change the root filesystem (when run in mount namespace)\n"
" --evasive-devices use any path to a device file if the original one\n"
" is inaccessible\n"
" --veth-pair IN=OUT map inside veth device name to outside one\n"
" --link-remap allow to link unlinked files back when possible\n"
" --action-script FILE add an external action script\n"
" -j|--" OPT_SHELL_JOB " allow to dump and restore shell jobs\n"
" -l|--" OPT_FILE_LOCKS " handle file locks, for safety, only used for container\n"
" -L|--libdir path to a plugin directory (by default " CR_PLUGIN_DEFAULT ")\n"
" --force-irmap force resolving names for inotify/fsnotify watches\n"
"\n"
"* Logging:\n"
" -o|--log-file FILE log file name\n"
" --log-pid enable per-process logging to separate FILE.pid files\n"
" -v[NUM] set logging level (higher level means more output):\n"
" -v1|-v - only errors and messages\n"
" -v2|-vv - also warnings (default level)\n"
" -v3|-vvv - also information messages and timestamps\n"
" -v4|-vvvv - lots of debug\n"
"\n"
"* Memory dumping options:\n"
" --track-mem turn on memory changes tracker in kernel\n"
" --prev-images-dir DIR path to images from previous dump (relative to -D)\n"
" --page-server send pages to page server (see options below as well)\n"
" --auto-dedup when used on dump it will deduplicate \"old\" data in\n"
" pages images of previous dump\n"
" when used on restore, as soon as page is restored, it\n"
" will be punched from the image.\n"
"\n"
"Page/Service server options:\n"
" --address ADDR address of server or service\n"
" --port PORT port of page server\n"
" -d|--daemon run in the background after creating socket\n"
"\n"
"Show options:\n"
" -f|--file FILE show contents of a checkpoint file\n"
" -F|--fields FIELDS show specified fields (comma separated)\n"
" -D|--images-dir DIR directory where to get images from\n"
" -c|--contents show contents of pages dumped in hexdump format\n"
" -p|--pid PID show files relevant to PID (filter -D flood)\n"
"\n"
"Other options:\n"
" -h|--help show this text\n"
" -V|--version show version\n"
" --ms don't check not yet merged kernel features\n"
);
return 0;
opt_pid_missing:
pr_msg("Error: pid not specified\n");
return 1;
bad_arg:
if (idx < 0) /* short option */
pr_msg("Error: invalid argument for -%c: %s\n",
opt, optarg);
else /* long option */
pr_msg("Error: invalid argument for --%s: %s\n",
long_opts[idx].name, optarg);
return 1;
}