core: general cgroup rework

Replace the very generic cgroup hookup with a much simpler one. With
this change only the high-level cgroup settings remain, the ability to
set arbitrary cgroup attributes is removed, so is support for adding
units to arbitrary cgroup controllers or setting arbitrary paths for
them (especially paths that are different for the various controllers).

This also introduces a new -.slice root slice, that is the parent of
system.slice and friends. This enables easy admin configuration of
root-level cgrouo properties.

This replaces DeviceDeny= by DevicePolicy=, and implicitly adds in
/dev/null, /dev/zero and friends if DeviceAllow= is used (unless this is
turned off by DevicePolicy=).

1 files changed, 139 insertions, 0 deletions

diff --git a/src/core/dbus-cgroup.c b/src/core/dbus-cgroup.c
new file mode 100644
index 000000000..08ee9c8db
--- /dev/null
+++ b/src/core/dbus-cgroup.c
@@ -0,0 +1,139 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2013 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 <dbus/dbus.h>
+
+#include "dbus-cgroup.h"
+
+static DEFINE_BUS_PROPERTY_APPEND_ENUM(bus_cgroup_append_device_policy, cgroup_device_policy, CGroupDevicePolicy);
+
+static int bus_cgroup_append_device_weights(DBusMessageIter *i, const char *property, void *data) {
+        DBusMessageIter sub, sub2;
+        CGroupContext *c = data;
+        CGroupBlockIODeviceWeight *w;
+
+        assert(i);
+        assert(property);
+        assert(c);
+
+        if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "(st)", &sub))
+                return -ENOMEM;
+
+        LIST_FOREACH(device_weights, w, c->blockio_device_weights) {
+
+                if (!dbus_message_iter_open_container(&sub, DBUS_TYPE_STRUCT, NULL, &sub2) ||
+                    !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &w->path) ||
+                    !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_UINT64, &w->weight) ||
+                    !dbus_message_iter_close_container(&sub, &sub2))
+                        return -ENOMEM;
+        }
+
+        if (!dbus_message_iter_close_container(i, &sub))
+                return -ENOMEM;
+
+        return 0;
+}
+
+static int bus_cgroup_append_device_bandwidths(DBusMessageIter *i, const char *property, void *data) {
+        DBusMessageIter sub, sub2;
+        CGroupContext *c = data;
+        CGroupBlockIODeviceBandwidth *b;
+
+        assert(i);
+        assert(property);
+        assert(c);
+
+        if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "(st)", &sub))
+                return -ENOMEM;
+
+        LIST_FOREACH(device_bandwidths, b, c->blockio_device_bandwidths) {
+
+                if (streq(property, "BlockIOReadBandwidth") != b->read)
+                        continue;
+
+                if (!dbus_message_iter_open_container(&sub, DBUS_TYPE_STRUCT, NULL, &sub2) ||
+                    !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &b->path) ||
+                    !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_UINT64, &b->bandwidth) ||
+                    !dbus_message_iter_close_container(&sub, &sub2))
+                        return -ENOMEM;
+        }
+
+        if (!dbus_message_iter_close_container(i, &sub))
+                return -ENOMEM;
+
+        return 0;
+}
+
+static int bus_cgroup_append_device_allow(DBusMessageIter *i, const char *property, void *data) {
+        DBusMessageIter sub, sub2;
+        CGroupContext *c = data;
+        CGroupDeviceAllow *a;
+
+        assert(i);
+        assert(property);
+        assert(c);
+
+        if (!dbus_message_iter_open_container(i, DBUS_TYPE_ARRAY, "(ss)", &sub))
+                return -ENOMEM;
+
+        LIST_FOREACH(device_allow, a, c->device_allow) {
+                const char *rwm;
+                char buf[4];
+                unsigned k = 0;
+
+                if (a->r)
+                        buf[k++] = 'r';
+                if (a->w)
+                        buf[k++] = 'w';
+                if (a->m)
+                        buf[k++] = 'm';
+
+                buf[k] = 0;
+                rwm = buf;
+
+                if (!dbus_message_iter_open_container(&sub, DBUS_TYPE_STRUCT, NULL, &sub2) ||
+                    !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &a->path) ||
+                    !dbus_message_iter_append_basic(&sub2, DBUS_TYPE_STRING, &rwm) ||
+                    !dbus_message_iter_close_container(&sub, &sub2))
+                        return -ENOMEM;
+        }
+
+        if (!dbus_message_iter_close_container(i, &sub))
+                return -ENOMEM;
+
+        return 0;
+}
+
+const BusProperty bus_cgroup_context_properties[] = {
+        { "CPUAccounting",           bus_property_append_bool,            "b",     offsetof(CGroupContext, cpu_accounting)     },
+        { "CPUShares",               bus_property_append_ul,              "t",     offsetof(CGroupContext, cpu_shares)         },
+        { "BlockIOAccounting",       bus_property_append_bool,            "b",     offsetof(CGroupContext, blockio_accounting) },
+        { "BlockIOWeight",           bus_property_append_ul,              "t",     offsetof(CGroupContext, blockio_weight)     },
+        { "BlockIODeviceWeight",     bus_cgroup_append_device_weights,    "a(st)", 0                                           },
+        { "BlockIOReadBandwidth",    bus_cgroup_append_device_bandwidths, "a(st)", 0                                           },
+        { "BlockIOWriteBandwidth",   bus_cgroup_append_device_bandwidths, "a(st)", 0                                           },
+        { "MemoryAccounting",        bus_property_append_bool,            "b",     offsetof(CGroupContext, memory_accounting)  },
+        { "MemoryLimit",             bus_property_append_uint64,          "t",     offsetof(CGroupContext, memory_limit)       },
+        { "MemorySoftLimit",         bus_property_append_uint64,          "t",     offsetof(CGroupContext, memory_soft_limit)  },
+        { "DevicePolicy",            bus_cgroup_append_device_policy,     "s",     offsetof(CGroupContext, device_policy)      },
+        { "DeviceAllow",             bus_cgroup_append_device_allow,      "a(ss)", 0                                           },
+        {}
+};