diff options
Diffstat (limited to 'src/nspawn')
| -rw-r--r-- | src/nspawn/nspawn-cgroup.c | 163 | ||||
| -rw-r--r-- | src/nspawn/nspawn-cgroup.h | 29 | ||||
| -rw-r--r-- | src/nspawn/nspawn.c | 148 |
3 files changed, 200 insertions, 140 deletions
diff --git a/src/nspawn/nspawn-cgroup.c b/src/nspawn/nspawn-cgroup.c new file mode 100644 index 0000000000..cfb4827de5 --- /dev/null +++ b/src/nspawn/nspawn-cgroup.c @@ -0,0 +1,163 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +/*** + This file is part of systemd. + + Copyright 2015 Lennart Poettering + + systemd 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. + + systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <sys/mount.h> + +#include "util.h" +#include "strv.h" +#include "mkdir.h" +#include "fileio.h" +#include "cgroup-util.h" + +#include "nspawn.h" +#include "nspawn-cgroup.h" + +int chown_cgroup(pid_t pid, uid_t uid_shift) { + _cleanup_free_ char *path = NULL, *fs = NULL; + _cleanup_close_ int fd = -1; + const char *fn; + int r; + + r = cg_pid_get_path(NULL, pid, &path); + if (r < 0) + return log_error_errno(r, "Failed to get container cgroup path: %m"); + + r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, path, NULL, &fs); + if (r < 0) + return log_error_errno(r, "Failed to get file system path for container cgroup: %m"); + + fd = open(fs, O_RDONLY|O_CLOEXEC|O_DIRECTORY); + if (fd < 0) + return log_error_errno(errno, "Failed to open %s: %m", fs); + + FOREACH_STRING(fn, + ".", + "tasks", + "notify_on_release", + "cgroup.procs", + "cgroup.clone_children", + "cgroup.controllers", + "cgroup.subtree_control", + "cgroup.populated") + if (fchownat(fd, fn, uid_shift, uid_shift, 0) < 0) + log_full_errno(errno == ENOENT ? LOG_DEBUG : LOG_WARNING, errno, + "Failed to chown() cgroup file %s, ignoring: %m", fn); + + return 0; +} + +int sync_cgroup(pid_t pid, bool unified_requested) { + _cleanup_free_ char *cgroup = NULL; + char tree[] = "/tmp/unifiedXXXXXX", pid_string[DECIMAL_STR_MAX(pid) + 1]; + bool undo_mount = false; + const char *fn; + int unified, r; + + unified = cg_unified(); + if (unified < 0) + return log_error_errno(unified, "Failed to determine whether the unified hierachy is used: %m"); + + if ((unified > 0) == unified_requested) + return 0; + + /* When the host uses the legacy cgroup setup, but the + * container shall use the unified hierarchy, let's make sure + * we copy the path from the name=systemd hierarchy into the + * unified hierarchy. Similar for the reverse situation. */ + + r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cgroup); + if (r < 0) + return log_error_errno(r, "Failed to get control group of " PID_FMT ": %m", pid); + + /* In order to access the unified hierarchy we need to mount it */ + if (!mkdtemp(tree)) + return log_error_errno(errno, "Failed to generate temporary mount point for unified hierarchy: %m"); + + if (unified) + r = mount("cgroup", tree, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "none,name=systemd,xattr"); + else + r = mount("cgroup", tree, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "__DEVEL__sane_behavior"); + if (r < 0) { + r = log_error_errno(errno, "Failed to mount unified hierarchy: %m"); + goto finish; + } + + undo_mount = true; + + fn = strjoina(tree, cgroup, "/cgroup.procs"); + (void) mkdir_parents(fn, 0755); + + sprintf(pid_string, PID_FMT, pid); + r = write_string_file(fn, pid_string, 0); + if (r < 0) + log_error_errno(r, "Failed to move process: %m"); + +finish: + if (undo_mount) + (void) umount(tree); + + (void) rmdir(tree); + return r; +} + +int create_subcgroup(pid_t pid, bool unified_requested) { + _cleanup_free_ char *cgroup = NULL; + const char *child; + int unified, r; + CGroupMask supported; + + /* In the unified hierarchy inner nodes may only only contain + * subgroups, but not processes. Hence, if we running in the + * unified hierarchy and the container does the same, and we + * did not create a scope unit for the container move us and + * the container into two separate subcgroups. */ + + if (!unified_requested) + return 0; + + unified = cg_unified(); + if (unified < 0) + return log_error_errno(unified, "Failed to determine whether the unified hierachy is used: %m"); + if (unified == 0) + return 0; + + r = cg_mask_supported(&supported); + if (r < 0) + return log_error_errno(r, "Failed to determine supported controllers: %m"); + + r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &cgroup); + if (r < 0) + return log_error_errno(r, "Failed to get our control group: %m"); + + child = strjoina(cgroup, "/payload"); + r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, child, pid); + if (r < 0) + return log_error_errno(r, "Failed to create %s subcgroup: %m", child); + + child = strjoina(cgroup, "/supervisor"); + r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, child, 0); + if (r < 0) + return log_error_errno(r, "Failed to create %s subcgroup: %m", child); + + /* Try to enable as many controllers as possible for the new payload. */ + (void) cg_enable_everywhere(supported, supported, cgroup); + return 0; +} diff --git a/src/nspawn/nspawn-cgroup.h b/src/nspawn/nspawn-cgroup.h new file mode 100644 index 0000000000..985fdfaad5 --- /dev/null +++ b/src/nspawn/nspawn-cgroup.h @@ -0,0 +1,29 @@ +/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/ + +#pragma once + +/*** + This file is part of systemd. + + Copyright 2015 Lennart Poettering + + systemd 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. + + systemd 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 systemd; If not, see <http://www.gnu.org/licenses/>. +***/ + +#include <sys/types.h> +#include <stdbool.h> + +int chown_cgroup(pid_t pid, uid_t uid_shift); +int sync_cgroup(pid_t pid, bool unified_requested); +int create_subcgroup(pid_t pid, bool unified_requested); diff --git a/src/nspawn/nspawn.c b/src/nspawn/nspawn.c index 7550ca057b..c106b58859 100644 --- a/src/nspawn/nspawn.c +++ b/src/nspawn/nspawn.c @@ -101,6 +101,7 @@ #include "nspawn-mount.h" #include "nspawn-network.h" #include "nspawn-expose-ports.h" +#include "nspawn-cgroup.h" typedef enum ContainerStatus { CONTAINER_TERMINATED, @@ -3292,141 +3293,6 @@ static int setup_uid_map(pid_t pid) { return 0; } -static int chown_cgroup(pid_t pid) { - _cleanup_free_ char *path = NULL, *fs = NULL; - _cleanup_close_ int fd = -1; - const char *fn; - int r; - - r = cg_pid_get_path(NULL, pid, &path); - if (r < 0) - return log_error_errno(r, "Failed to get container cgroup path: %m"); - - r = cg_get_path(SYSTEMD_CGROUP_CONTROLLER, path, NULL, &fs); - if (r < 0) - return log_error_errno(r, "Failed to get file system path for container cgroup: %m"); - - fd = open(fs, O_RDONLY|O_CLOEXEC|O_DIRECTORY); - if (fd < 0) - return log_error_errno(errno, "Failed to open %s: %m", fs); - - FOREACH_STRING(fn, - ".", - "tasks", - "notify_on_release", - "cgroup.procs", - "cgroup.clone_children", - "cgroup.controllers", - "cgroup.subtree_control", - "cgroup.populated") - if (fchownat(fd, fn, arg_uid_shift, arg_uid_shift, 0) < 0) - log_full_errno(errno == ENOENT ? LOG_DEBUG : LOG_WARNING, errno, - "Failed to chown() cgroup file %s, ignoring: %m", fn); - - return 0; -} - -static int sync_cgroup(pid_t pid) { - _cleanup_free_ char *cgroup = NULL; - char tree[] = "/tmp/unifiedXXXXXX", pid_string[DECIMAL_STR_MAX(pid) + 1]; - bool undo_mount = false; - const char *fn; - int unified, r; - - unified = cg_unified(); - if (unified < 0) - return log_error_errno(unified, "Failed to determine whether the unified hierachy is used: %m"); - - if ((unified > 0) == arg_unified_cgroup_hierarchy) - return 0; - - /* When the host uses the legacy cgroup setup, but the - * container shall use the unified hierarchy, let's make sure - * we copy the path from the name=systemd hierarchy into the - * unified hierarchy. Similar for the reverse situation. */ - - r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, pid, &cgroup); - if (r < 0) - return log_error_errno(r, "Failed to get control group of " PID_FMT ": %m", pid); - - /* In order to access the unified hierarchy we need to mount it */ - if (!mkdtemp(tree)) - return log_error_errno(errno, "Failed to generate temporary mount point for unified hierarchy: %m"); - - if (unified) - r = mount("cgroup", tree, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "none,name=systemd,xattr"); - else - r = mount("cgroup", tree, "cgroup", MS_NOSUID|MS_NOEXEC|MS_NODEV, "__DEVEL__sane_behavior"); - if (r < 0) { - r = log_error_errno(errno, "Failed to mount unified hierarchy: %m"); - goto finish; - } - - undo_mount = true; - - fn = strjoina(tree, cgroup, "/cgroup.procs"); - (void) mkdir_parents(fn, 0755); - - sprintf(pid_string, PID_FMT, pid); - r = write_string_file(fn, pid_string, 0); - if (r < 0) - log_error_errno(r, "Failed to move process: %m"); - -finish: - if (undo_mount) - (void) umount(tree); - - (void) rmdir(tree); - return r; -} - -static int create_subcgroup(pid_t pid) { - _cleanup_free_ char *cgroup = NULL; - const char *child; - int unified, r; - CGroupMask supported; - - /* In the unified hierarchy inner nodes may only only contain - * subgroups, but not processes. Hence, if we running in the - * unified hierarchy and the container does the same, and we - * did not create a scope unit for the container move us and - * the container into two separate subcgroups. */ - - if (!arg_keep_unit) - return 0; - - if (!arg_unified_cgroup_hierarchy) - return 0; - - unified = cg_unified(); - if (unified < 0) - return log_error_errno(unified, "Failed to determine whether the unified hierachy is used: %m"); - if (unified == 0) - return 0; - - r = cg_mask_supported(&supported); - if (r < 0) - return log_error_errno(r, "Failed to determine supported controllers: %m"); - - r = cg_pid_get_path(SYSTEMD_CGROUP_CONTROLLER, 0, &cgroup); - if (r < 0) - return log_error_errno(r, "Failed to get our control group: %m"); - - child = strjoina(cgroup, "/payload"); - r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, child, pid); - if (r < 0) - return log_error_errno(r, "Failed to create %s subcgroup: %m", child); - - child = strjoina(cgroup, "/supervisor"); - r = cg_create_and_attach(SYSTEMD_CGROUP_CONTROLLER, child, 0); - if (r < 0) - return log_error_errno(r, "Failed to create %s subcgroup: %m", child); - - /* Try to enable as many controllers as possible for the new payload. */ - (void) cg_enable_everywhere(supported, supported, cgroup); - return 0; -} - static int load_settings(void) { _cleanup_(settings_freep) Settings *settings = NULL; _cleanup_fclose_ FILE *f = NULL; @@ -4042,15 +3908,17 @@ int main(int argc, char *argv[]) { if (r < 0) goto finish; - r = sync_cgroup(pid); + r = sync_cgroup(pid, arg_unified_cgroup_hierarchy); if (r < 0) goto finish; - r = create_subcgroup(pid); - if (r < 0) - goto finish; + if (arg_keep_unit) { + r = create_subcgroup(pid, arg_unified_cgroup_hierarchy); + if (r < 0) + goto finish; + } - r = chown_cgroup(pid); + r = chown_cgroup(pid, arg_uid_shift); if (r < 0) goto finish; |