[CRIU] [PATCH 1/5] crtools: preload libraries
Andrew Vagin
avagin at parallels.com
Fri Dec 6 01:45:57 PST 2013
On Thu, Dec 05, 2013 at 09:58:55PM +0400, Andrey Vagin wrote:
> Libraries is going to be used for dumping and restoring
> external dependencies (e.g. dbus, systemd journal sockets)
>
> A libary can have the cr_init() function for initialization.
>
> The criu devel package should contain log.h, plugin.h. Probably
> this package should create the criu directory in /usr/include.
>
> Signed-off-by: Andrey Vagin <avagin at openvz.org>
> ---
> Makefile | 4 +-
> Makefile.crtools | 1 +
> cr-dump.c | 6 +++
> cr-restore.c | 27 +++++++----
> crtools.c | 13 +++++-
> include/cr_options.h | 1 +
> include/criu-plugin.h | 26 +++++++++++
> include/plugin.h | 22 +++++++++
> lib.c | 123 ++++++++++++++++++++++++++++++++++++++++++++++++++
> 9 files changed, 211 insertions(+), 12 deletions(-)
> create mode 100644 include/criu-plugin.h
> create mode 100644 include/plugin.h
> create mode 100644 lib.c
>
> diff --git a/Makefile b/Makefile
> index cd312e7..1cdae52 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -82,7 +82,7 @@ cflags-y += -iquote $(ARCH_DIR) -iquote $(ARCH_DIR)/include
> cflags-y += -fno-strict-aliasing
> export cflags-y
>
> -LIBS := -lrt -lpthread -lprotobuf-c
> +LIBS := -lrt -lpthread -lprotobuf-c -ldl
>
> DEFINES += -D_FILE_OFFSET_BITS=64
> DEFINES += -D_GNU_SOURCE
> @@ -167,7 +167,7 @@ PROGRAM-BUILTINS += $(ARCH_DIR)/vdso-pie.o
>
> $(PROGRAM): $(SYSCALL-LIB) $(ARCH-LIB) $(PROGRAM-BUILTINS)
> $(E) " LINK " $@
> - $(Q) $(CC) $(CFLAGS) $^ $(LIBS) $(LDFLAGS) -o $@
> + $(Q) $(CC) $(CFLAGS) $^ $(LIBS) $(LDFLAGS) -rdynamic -o $@
>
> zdtm: all
> $(Q) $(MAKE) -C test/zdtm all
> diff --git a/Makefile.crtools b/Makefile.crtools
> index 3030ce9..227944c 100644
> --- a/Makefile.crtools
> +++ b/Makefile.crtools
> @@ -56,6 +56,7 @@ obj-y += string.o
> obj-y += sigframe.o
> obj-y += arch/$(ARCH)/vdso.o
> obj-y += cr-service.o
> +obj-y += lib.o
>
> ifneq ($(MAKECMDGOALS),clean)
> incdeps := y
> diff --git a/cr-dump.c b/cr-dump.c
> index ffae7ff..3c03ab6 100644
> --- a/cr-dump.c
> +++ b/cr-dump.c
> @@ -70,6 +70,7 @@
> #include "vdso.h"
> #include "vma.h"
> #include "cr-service.h"
> +#include "plugin.h"
>
> #include "asm/dump.h"
>
> @@ -1670,6 +1671,9 @@ int cr_dump_tasks(pid_t pid)
> if (init_stats(DUMP_STATS))
> goto err;
>
> + if (cr_lib_init())
> + goto err;
> +
> if (kerndat_init())
> goto err;
>
> @@ -1753,6 +1757,8 @@ err:
>
> close_cr_fdset(&glob_fdset);
>
> + cr_lib_fini();
> +
> if (!ret) {
> /*
> * It might be a migration case, where we're asked
> diff --git a/cr-restore.c b/cr-restore.c
> index 6a0637e..46dd262 100644
> --- a/cr-restore.c
> +++ b/cr-restore.c
> @@ -67,6 +67,7 @@
> #include "vma.h"
> #include "kerndat.h"
> #include "rst-malloc.h"
> +#include "plugin.h"
>
> #include "parasite-syscall.h"
>
> @@ -1616,33 +1617,41 @@ static int prepare_task_entries()
>
> int cr_restore_tasks(void)
> {
> - if (check_img_inventory() < 0)
> + int ret = -1;
> +
> + if (cr_lib_init())
> return -1;
>
> + if (check_img_inventory() < 0)
> + goto err;
> +
> if (init_stats(RESTORE_STATS))
> - return -1;
> + goto err;
>
> if (kerndat_init_rst())
> - return -1;
> + goto err;
>
> timing_start(TIME_RESTORE);
>
> if (cpu_init() < 0)
> - return -1;
> + goto err;
>
> if (vdso_init())
> - return -1;
> + goto err;
>
> if (prepare_task_entries() < 0)
> - return -1;
> + goto err;
>
> if (prepare_pstree() < 0)
> - return -1;
> + goto err;
>
> if (crtools_prepare_shared() < 0)
> - return -1;
> + goto err;
>
> - return restore_root_task(root_item);
> + ret = restore_root_task(root_item);
> +err:
> + cr_lib_fini();
> + return ret;
> }
>
> static long restorer_get_vma_hint(pid_t pid, struct list_head *tgt_vma_list,
> diff --git a/crtools.c b/crtools.c
> index ab885e6..53d67dd 100644
> --- a/crtools.c
> +++ b/crtools.c
> @@ -16,6 +16,8 @@
> #include <netinet/in.h>
> #include <arpa/inet.h>
>
> +#include <dlfcn.h>
> +
> #include "asm/types.h"
>
> #include "compiler.h"
> @@ -31,6 +33,7 @@
> #include "tty.h"
> #include "file-lock.h"
> #include "cr-service.h"
> +#include "plugin.h"
>
> struct cr_options opts;
>
> @@ -95,7 +98,7 @@ int main(int argc, char *argv[])
> return -1;
>
> while (1) {
> - static const char short_opts[] = "dsRf:t:p:hcD:o:n:v::xVr:jlW:";
> + static const char short_opts[] = "dsRf:t:p:hcD:o:n:v::xVr:jlW:L:";
> static struct option long_opts[] = {
> { "tree", required_argument, 0, 't' },
> { "pid", required_argument, 0, 'p' },
> @@ -129,6 +132,7 @@ int main(int argc, char *argv[])
> { "prev-images-dir", required_argument, 0, 53},
> { "ms", no_argument, 0, 54},
> { "track-mem", no_argument, 0, 55},
> + { "libdir", required_argument, 0, 'L'},
> { },
> };
>
> @@ -271,6 +275,13 @@ int main(int argc, char *argv[])
> case 54:
> opts.check_ms_kernel = true;
> break;
> + case 'L':
> + opts.libdir = strdup(optarg);
> + if (opts.libdir == NULL) {
> + pr_perror("Can't allocate memory");
> + return -1;
> + }
> + break;
> case 'V':
> pr_msg("Version: %s\n", CRIU_VERSION);
> if (strcmp(CRIU_GITID, "0"))
> diff --git a/include/cr_options.h b/include/cr_options.h
> index b90b4e1..5a4676c 100644
> --- a/include/cr_options.h
> +++ b/include/cr_options.h
> @@ -29,6 +29,7 @@ struct cr_options {
> char *pidfile;
> struct list_head veth_pairs;
> struct list_head scripts;
> + char *libdir;
> bool use_page_server;
> unsigned short ps_port;
> char *addr;
> diff --git a/include/criu-plugin.h b/include/criu-plugin.h
> new file mode 100644
> index 0000000..44abb2a
> --- /dev/null
> +++ b/include/criu-plugin.h
> @@ -0,0 +1,26 @@
> +/*
> + This file defines types and macros for CRIU plugins.
> + Copyright (C) 2013 Parallels, Inc
> +
> + This program is free software; you can redistribute it and/or modify
> + it under the terms of the GNU General Public License as published by
> + the Free Software Foundation; either version 2 of the License, or
> + (at your option) any later version.
> +
> + This program 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 General Public License for more details.
> +
> + You should have received a copy of the GNU General Public License
> + along with this program; if not, write to the Free Software
> + Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
> + */
> +
> +#ifndef __CRIU_PLUGIN_H__
> +#define __CRIU_PLUGIN_H__
> +
> +typedef int (cr_plugin_init_t)(void);
> +typedef void (cr_plugin_fini_t)(void);
> +
> +#endif
> diff --git a/include/plugin.h b/include/plugin.h
> new file mode 100644
> index 0000000..8653a5b
> --- /dev/null
> +++ b/include/plugin.h
> @@ -0,0 +1,22 @@
> +#ifndef __CR_PLUGIN_H__
> +#define __CR_PLUGIN_H__
> +
> +#include "criu-plugin.h"
> +
> +struct cr_plugin_entry {
> + union {
> + cr_plugin_fini_t *cr_fini;
> + };
> +
> + struct cr_plugin_entry *next;
> +};
> +
> +struct cr_plugins {
> + struct cr_plugin_entry *cr_fini;
> +};
> +
> +extern struct cr_plugins cr_plugins;
> +
> +void cr_lib_fini(void);
> +int cr_lib_init(void);
> +#endif
> diff --git a/lib.c b/lib.c
> new file mode 100644
> index 0000000..387bb84
> --- /dev/null
> +++ b/lib.c
> @@ -0,0 +1,123 @@
> +#include <stdlib.h>
> +#include <string.h>
> +#include <dirent.h>
> +#include <errno.h>
> +#include <stdio.h>
> +#include <dlfcn.h>
> +
> +#include "cr_options.h"
> +#include "plugin.h"
> +#include "log.h"
> +#include "xmalloc.h"
> +
> +struct cr_plugins cr_plugins;
> +
> +static int cr_lib_load(char *path)
> +{
> + struct cr_plugin_entry *ce;
> + cr_plugin_init_t *f_init;
> + cr_plugin_fini_t *f_fini;
> + void *h;
> +
> + h = dlopen(path, RTLD_LAZY);
> + if (h == NULL) {
> + pr_err("Unable to load %s: %s", path, dlerror());
> + return -1;
> + }
> +
> + ce = NULL;
> + f_fini = dlsym(h, "cr_plugin_fini");
> + if (f_fini) {
> + ce = xmalloc(sizeof(struct cr_plugin_entry));
> + if (ce == NULL)
> + return -1;
> + ce->cr_fini = f_fini;
> + }
> +
> + f_init = dlsym(h, "cr_plugin_init");
> + if (f_init && f_init()) {
> + xfree(ce);
> + return -1;
> + }
> +
> + if (ce) {
> + ce->next = cr_plugins.cr_fini;
> + cr_plugins.cr_fini = ce;
> + }
> +
> + return 0;
> +}
> +
> +void cr_lib_fini(void)
> +{
> + struct cr_plugin_entry *ce;
> +
> + while (cr_plugins.cr_fini) {
> + ce = cr_plugins.cr_fini;
> + cr_plugins.cr_fini = cr_plugins.cr_fini->next;
> +
> + ce->cr_fini();
> + xfree(ce);
> + }
> +}
> +
> +int cr_lib_init(void)
> +{
> + int exit_code = -1;
> + DIR *d;
> +
> + memset(&cr_plugins, 0, sizeof(cr_plugins));
> +
> + if (opts.libdir == NULL) {
> + char *path;
> +
> + path = getenv("CRIU_LIBS_DIR");
> + if (path == NULL)
> + return 0;
> +
> + opts.libdir = strdup(path);
> + if (opts.libdir == NULL) {
> + pr_perror("Can't allocate memory");
> + return -1;
> + }
> + }
> +
> + d = opendir(opts.libdir);
> + if (d == 0) {
> + pr_perror("Unable to open directory %s", opts.libdir);
> + return -1;
> + }
> +
> + while (1) {
> + char path[PATH_MAX];
> + struct dirent *de;
> + int len;
> +
> + errno = 0;
> + de = readdir(d);
> + if (de == NULL) {
> + if (errno == 0)
> + break;
> + pr_perror("Unable to read the libraries directory");
> + goto err;
> + }
> +
> + len = strlen(de->d_name);
> +
> + if (len < 3 || strncmp(de->d_name + len - 3, ".so", 3))
> + continue;
> +
> + snprintf(path, sizeof(path), "%s/%s", opts.libdir, de->d_name);
> +
> + if (cr_lib_load(path))
> + goto err;
> + }
> +
> + exit_code = 0;
> +err:
> + closedir(d);
> +
if (exit_code)
> + cr_lib_fini();
> +
> + return exit_code;
> +}
> --
> 1.8.3.1
>
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