#ifndef _LVE_CGROUP_LIB_H_
#define _LVE_CGROUP_LIB_H_

#include <linux/version.h>
#include "lve_kmod_c.h"

struct cgroup;
struct vfsmount;


enum subsys_id {
	CPU_SUBSYS = 0,
	MEM_SUBSYS = 1,
	BLK_SUBSYS = 2,
	FREEZER_SUBSYS = 3,
	PIDS_SUBSYS = 4,
	NETMARK_SUBSYS = 5,
#if OPENVZ_VERSION > 0
	/* must last */
	UB_SUBSYS,
#endif
	NR_SUBSYS,
};

#if OPENVZ_VERSION == 0
#define CGROUPS_SUPPORTED 0xFF
#elif RHEL_MAJOR == 7
#define CGROUPS_SUPPORTED (BIT(CPU_SUBSYS) | BIT(FREEZER_SUBSYS) | \
			   BIT(NETMARK_SUBSYS))
#else
#error "please define supported version"
#endif

#define RESOURCE_SUBSYS_MASK (BIT(PIDS_SUBSYS) | BIT(MEM_SUBSYS) | \
			       BIT(NETMARK_SUBSYS))

enum lve_cgroup_open_flags {
	LVE_CGRP_CREAT      = 0x0001,	/* create if not found */
	LVE_CGRP_EXCL       = 0x0002,	/* fail if already exist */
};

static inline int get_flags(void)
{
#ifndef LVE_PER_VE
	return LVE_CGRP_CREAT;
#else
	return 0;
#endif
}

struct cgrp_mount {
	struct vfsmount *mnt_root;
	struct dentry *cgrp_root;
};

extern struct cgrp_mount cmnt[NR_SUBSYS];

struct params {
	const char *p_name;
	unsigned p_subsys;
};

struct lvp_private {
	struct dentry *lve_root[NR_SUBSYS];
};

enum param_id {
	PARAM_CPU_STAT = 0,
	PARAM_CPU_LIMIT,
	PARAM_CPU_CHWT,
	PARAM_CPU_ENTER,
	PARAM_CPU_THROTTLE,
	PARAM_PIDS_ENTER,

#ifdef HAVE_PIDS_CGRP
	PARAM_PIDS_LIMIT,
	PARAM_PIDS_CURRENT,
	PARAM_PIDS_EVENTS,
#endif
	PARAM_FREEZER_ENTER,

	PARAM_MEM_ENTER,
	PARAM_MEM_LIMIT,
	PARAM_MEM_STAT,
	PARAM_MEM_ANON_STAT,
	PARAM_MEM_FAILCNT,

	PARAM_BLK_ENTER,

	PARAM_NETMARK_ENTER,
	PARAM_NETMARK_MARK,

	PARAM_FILP_MAX
};


/* connected to each creates context / LVE */
struct c_private {
#if OPENVZ_VERSION > 0
	struct user_beancounter *lve_ub;
#endif
	struct dentry *cgrp[NR_SUBSYS];
	struct file *filps[PARAM_FILP_MAX];
	unsigned long unlink_id;
	int flags;
};

/* we can't use an container_of macro due type check error */
#define os_lve(cp) ((struct light_ve *)( (char *)(cp) - \
		    offsetof(struct light_ve ,lve_private) ))

extern struct cgrp_mount cmnt[NR_SUBSYS];

#define MAX_GRP_NAMESZ 25
#define UNLINK_FORMAT "rmv-%lu"

#ifdef LVE_PER_VE
#define LVP_FMT "%u"
#else
#define LVP_FMT "lvp%u"
#endif

#define LVE_PREFIX "lve"
#define LVE_FMT LVE_PREFIX "%u"
#define IS_LVE_NAME(s) (!strncmp(s, LVE_PREFIX, sizeof(LVE_PREFIX) - 1))

unsigned long get_unlink_id(void);
int cgrp_obfuscate(struct dentry *cgrp, char *unlink_name);


int mount_cgroup_root_fs(struct cgrp_mount *cmnt, u64 supported);
void umount_cgroup_root_fs(struct cgrp_mount *cmnt);

extern u64 ioprio_weight[];

struct file *cgrp_param_open(struct vfsmount *vfsmnt,
				   struct dentry *grp, const char *param);
void cgrp_param_release(struct file *filp);
int cgrp_param_set_u64(struct file *filp, __u64 data);
int cgrp_param_set_s64(struct file *filp, s64 data);
int cgrp_param_set_string(struct file *filp, const char *buf, size_t nbytes);
int cgrp_populate_dir(struct dentry **cgrp, struct file **filp,
		      const struct params *p, int nr_params);
/* return <0 if error */
__s64 cgrp_param_get(struct file *filp);
int cgrp_param_get_string(struct file *filp, char *buf, size_t nbytes);
int cgrp_param_open_write_string(struct vfsmount *mnt, struct dentry *cgrp,
				 const char *param, const char *buf,
				 unsigned count);

int cgrp_param_open_read_string(struct vfsmount *mnt, struct dentry *cgrp,
				 const char *param, char *buf,
				 unsigned count);
struct dentry *lve_cgroup_kernel_open(struct dentry *parent,
		enum lve_cgroup_open_flags flags, const char *name);
int lve_cgroup_kernel_remove(struct dentry *cgrp);
void lve_cgroup_kernel_close(struct dentry *cgrp);

static inline struct cgroup *__d_cgrp(struct dentry *dentry)
{
	return dentry ? dentry->d_fsdata : NULL;
}

struct dentry *lve_cgroup_get_root(struct vfsmount *mnt);
static inline bool lve_cgroup_is_root(struct dentry *d)
{
	return d == d->d_parent;
}

#endif