image: Add bits and pieces for cgroups image

The exact structure of the image will be revealed in the
next patch(es). What is important here, is that cgroup
image is somewhat new.

It will likely contain arrays of objects of different types,
so I introduce the "header" object, that will link these
arrays using pb repeated fields. This will help us to avoid
many image files for different cgroup objects and will make
the amount of write()-s required be 1.
Signed-off-by: Pavel Emelyanov <xemul@parallels.com>

cr-show.c

@@ -296,6 +296,7 @@ static struct show_image_info show_infos[] = {
 	SHOW_VERT(FS),
 	SHOW_VERT(GHOST_FILE),
 	SHOW_VERT(MM),
+	SHOW_VERT(CGROUP),
 
 	SHOW_PLAINS(REG_FILE),
 	SHOW_PLAINS(NS_FILE),

image-desc.c

@@ -76,6 +76,7 @@ struct cr_fd_desc_tmpl fdset_template[CR_FD_MAX] = {
 	FD_ENTRY(SIGNAL,	"signal-s-%d"),
 	FD_ENTRY(PSIGNAL,	"signal-p-%d"),
 	FD_ENTRY(TUNFILE,	"tunfile"),
+	FD_ENTRY(CGROUP,	"cgroup"),
 
 	[CR_FD_STATS] = {
 		.fmt	= "stats-%s",

include/image-desc.h

@@ -74,6 +74,7 @@ enum {
 	CR_FD_FANOTIFY_FILE,
 	CR_FD_FANOTIFY_MARK,
 	CR_FD_TUNFILE,
+	CR_FD_CGROUP,
 	_CR_FD_GLOB_TO,
 
 	CR_FD_TMPFS_IMG,

include/magic.h

@@ -72,6 +72,7 @@
 #define NETLINK_SK_MAGIC	0x58005614 /* Perm */
 #define NS_FILES_MAGIC		0x61394011 /* Nyandoma */
 #define TUNFILE_MAGIC		0x57143751 /* Kalyazin */
+#define CGROUP_MAGIC		0x59383330 /* Tikhvin */
 
 #define IFADDR_MAGIC		RAW_IMAGE_MAGIC
 #define ROUTE_MAGIC		RAW_IMAGE_MAGIC

include/protobuf-desc.h

@@ -50,6 +50,7 @@ enum {
 	PB_SIGINFO,
 	PB_TUNFILE,
 	PB_IRMAP_CACHE,
+	PB_CGROUP,
 
 	/* PB_AUTOGEN_STOP */
 

protobuf-desc.c

@@ -57,6 +57,7 @@
 #include "protobuf/sk-netlink.pb-c.h"
 #include "protobuf/vma.pb-c.h"
 #include "protobuf/tun.pb-c.h"
+#include "protobuf/cgroup.pb-c.h"
 
 struct cr_pb_message_desc cr_pb_descs[PB_MAX];
 

protobuf/Makefile

@@ -59,6 +59,7 @@ proto-obj-y	+= pagemap.o
 proto-obj-y	+= siginfo.o
 proto-obj-y	+= rpc.o
 proto-obj-y	+= ext-file.o
+proto-obj-y	+= cgroup.o
 
 proto		:= $(proto-obj-y:.o=)
 proto-c		:= $(proto-obj-y:.o=.pb-c.c)

protobuf/cgroup.proto

+message controller_entry {
+	required string name	= 1;
+	required string path	= 2;
+}
+
+message cg_set_entry {
+	required uint32			id	= 1;
+	repeated controller_entry	ctls	= 2;
+}
+
+message cgroup_entry {
+	repeated cg_set_entry	sets	= 1;
+}

protobuf/core.proto

@@ -17,6 +17,8 @@ message task_core_entry {
 
 	optional task_timers_entry	timers		= 7;
 	optional task_rlimits_entry	rlimits		= 8;
+
+	optional uint32			cg_set		= 9;
 }
 
 message task_kobj_ids_entry {

protobuf/inventory.proto

@@ -5,4 +5,5 @@ message inventory_entry {
 	optional bool			fdinfo_per_id	= 2;
 	optional task_kobj_ids_entry	root_ids	= 3;
 	optional bool			ns_per_id	= 4;
+	optional uint32			root_cg_set	= 5;
 }