/*
 *  linux/kernel/vserver/limit.c
 *
 *  Virtual Server: Context Limits
 *
 *  Copyright (C) 2004  Herbert Pötzl
 *
 *  V0.01  broken out from vcontext V0.05
 *
 */

#include <linux/config.h>
#include <linux/vserver/limit.h>
#include <linux/vserver/context.h>
#include <linux/vserver/switch.h>
#include <linux/vinline.h>

#include <asm/errno.h>
#include <asm/uaccess.h>


static int is_valid_rlimit(int id)
{
	int valid = 0;

	switch (id) {
		case RLIMIT_NPROC:
		case RLIMIT_AS:
		case RLIMIT_RSS:
		case RLIMIT_MEMLOCK:
		case RLIMIT_NOFILE:
			valid = 1;
			break;
	}
	return valid;
}

static inline uint64_t vc_get_rlim(struct vx_info *vxi, int id)
{
	unsigned long limit;

	limit = vxi->limit.rlim[id];
	if (limit == RLIM_INFINITY)
		return CRLIM_INFINITY;
	return limit;	
}

int vc_get_rlimit(uint32_t id, void __user *data)
{
	struct vx_info *vxi;
	struct vcmd_ctx_rlimit_v0 vc_data;

	if (copy_from_user (&vc_data, data, sizeof(vc_data)))
		return -EFAULT;
	if (!is_valid_rlimit(vc_data.id))
		return -ENOTSUPP;
		
	vxi = locate_vx_info(id);
	if (!vxi)
		return -ESRCH;

	vc_data.maximum = vc_get_rlim(vxi, vc_data.id);
	vc_data.minimum = CRLIM_UNSET;
	vc_data.softlimit = CRLIM_UNSET;
	put_vx_info(vxi);

	if (copy_to_user (data, &vc_data, sizeof(vc_data)))
		return -EFAULT;
	return 0;
}

int vc_set_rlimit(uint32_t id, void __user *data)
{
	struct vx_info *vxi;
	struct vcmd_ctx_rlimit_v0 vc_data;

	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RESOURCE))
		return -EPERM;
	if (copy_from_user (&vc_data, data, sizeof(vc_data)))
		return -EFAULT;
	if (!is_valid_rlimit(vc_data.id))
		return -ENOTSUPP;

	vxi = locate_vx_info(id);
	if (!vxi)
		return -ESRCH;

	if (vc_data.maximum != CRLIM_KEEP)
		vxi->limit.rlim[vc_data.id] = vc_data.maximum;
	printk("setting [%d] = %d\n", vc_data.id, (int)vc_data.maximum);
	put_vx_info(vxi);

	return 0;
}

int vc_get_rlimit_mask(uint32_t id, void __user *data)
{
	static struct vcmd_ctx_rlimit_mask_v0 mask = {
			/* minimum */
		0
		,	/* softlimit */
		0
		,	/* maximum */
		(1 << RLIMIT_NPROC) |
		(1 << RLIMIT_NOFILE) |
		(1 << RLIMIT_MEMLOCK) |
		(1 << RLIMIT_AS) |
		(1 << RLIMIT_RSS)
		};

	if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RESOURCE))
		return -EPERM;
	if (copy_to_user(data, &mask, sizeof(mask)))
                return -EFAULT;
	return 0;
}


void vx_vsi_meminfo(struct sysinfo *val)
{
	struct vx_info *vxi = current->vx_info;
	unsigned long v;

	v = vxi->limit.rlim[RLIMIT_RSS];
	if (v != RLIM_INFINITY)
		val->totalram = min(val->totalram, v);
	v = atomic_read(&vxi->limit.res[RLIMIT_RSS]);
	val->freeram = (v < val->totalram) ? val->totalram - v : 0;
	val->bufferram = 0;
        val->totalhigh = 0;
        val->freehigh = 0;
	return;
}

void vx_vsi_swapinfo(struct sysinfo *val)
{
	struct vx_info *vxi = current->vx_info;
	unsigned long w,v;

	v = vxi->limit.rlim[RLIMIT_RSS];
	w = vxi->limit.rlim[RLIMIT_AS];
	if (w != RLIM_INFINITY)
		val->totalswap = min(val->totalswap, w -
		((v != RLIM_INFINITY) ? v : 0));
	w = atomic_read(&vxi->limit.res[RLIMIT_AS]);
	val->freeswap = (w < val->totalswap) ? val->totalswap - w : 0;
	return;
}