From: Ivana Hutarova Varekova <varekova@redhat.com>
Date: Mon, 25 Oct 2010 10:32:19 +0000 (+0200)
Subject: add devices controller logic to cgsnapshot tool
X-Git-Tag: v0.37~44
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=cdb2e31895cae5ac5183ba3bd1dde81e067334d8;p=thirdparty%2Flibcgroup.git

add devices controller logic to cgsnapshot tool

This patch adds devices controller logic to cgsnapshot tool
so now it is able to parse devices.

CHANGELOG:
 * incorporate Jan's feedback

EXAMPLE:
# cgget -g devices /dev
/dev:
devices.list=c 1:* wm
devices.deny=
devices.allow=

# cgsnapshot -b samples/blacklist.conf -w samples/whitelist.conf
# Configuration file generated by cgsnapshot
mount {
	cpuset = /cgroup/1;
	cpu = /cgroup/2;
	cpuacct = /cgroup/3;
	memory = /cgroup/4;
	devices = /cgroup/5;
	freezer = /cgroup/6;
	net_cls = /cgroup/7;
}

group dev {
	perm {
		admin {
			uid = root;
			gid = root;
		}
		task {
			uid = root;
			gid = root;
		}
	}
	devices {
		devices.deny="a *:* rwm";
		devices.allow="c 1:* wm";
	}
}

Signed-off-by: Ivana Hutarova Varekova <varekova@redhat.com>
Signed-off-by: Jan Safranek <jsafrane@redhat.com>
---

diff --git a/samples/cgsnapshot_blacklist.conf b/samples/cgsnapshot_blacklist.conf
index ff14b7d9..28924692 100644
--- a/samples/cgsnapshot_blacklist.conf
+++ b/samples/cgsnapshot_blacklist.conf
@@ -11,8 +11,6 @@ cpuacct.stat
 cpuacct.usage_percpu
 
 #devices
-devices.deny
-devices.allow
 
 #cpuset
 
diff --git a/samples/cgsnapshot_whitelist.conf b/samples/cgsnapshot_whitelist.conf
index c8481ea6..2c9ab238 100644
--- a/samples/cgsnapshot_whitelist.conf
+++ b/samples/cgsnapshot_whitelist.conf
@@ -20,6 +20,9 @@ cpu.rt_period_us
 cpuacct.usage
 
 #devices
+devices.deny
+devices.allow
+devices.list
 
 #cpuset
 cpuset.memory_spread_slab
diff --git a/src/tools/cgsnapshot.c b/src/tools/cgsnapshot.c
index 5e2c7adc..a593f91a 100644
--- a/src/tools/cgsnapshot.c
+++ b/src/tools/cgsnapshot.c
@@ -280,6 +280,7 @@ static int display_cgroup_data(struct cgroup *group,
 	int bl, wl = 0; /* is on the blacklist/whitelist flag */
 	int nr_var = 0;
 	char *name;
+	char *output_name;
 	struct cgroup_controller *group_controller = NULL;
 	char *value = NULL;
 	char var_path[FILENAME_MAX];
@@ -325,8 +326,11 @@ static int display_cgroup_data(struct cgroup *group,
 			ret = stat(var_path, &sb);
 			/* freezer.state is not in root group so ret != 0,
 			 * but it should be listed
+			 * device.list should be read to create
+			 * device.allow input
 			 */
-			if ((ret == 0) && ((sb.st_mode & S_IWUSR) == 0)) {
+			if ((ret == 0) && ((sb.st_mode & S_IWUSR) == 0) &&
+			    (strcmp("devices.list", name) != 0)) {
 				/* variable is not writable */
 				continue;
 			}
@@ -352,6 +356,23 @@ static int display_cgroup_data(struct cgroup *group,
 					"neither blacklisted nor "\
 					"whitelisted\n", name);
 
+			output_name = name;
+
+			/* deal with devices variables:
+			 * - omit devices.deny and device.allow,
+			 * - generate devices.{deny,allow} from
+			 * device.list variable (deny all and then
+			 * all device.list devices */
+			if ((strcmp("devices.deny", name) == 0) ||
+				(strcmp("devices.allow", name) == 0)) {
+				continue;
+			}
+			if (strcmp("devices.list", name) == 0) {
+				output_name = "devices.allow";
+				fprintf(of,
+					"\t\tdevices.deny=\"a *:* rwm\";\n");
+			}
+
 			ret = cgroup_get_value_string(group_controller,
 				name, &value);
 
@@ -363,7 +384,7 @@ static int display_cgroup_data(struct cgroup *group,
 					name);
 				goto err;
 			}
-			fprintf(of, "\t\t%s=\"%s\";\n", name, value);
+			fprintf(of, "\t\t%s=\"%s\";\n", output_name, value);
 		}
 		fprintf(of, "\t}\n");
 	}