You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
135 lines
2.8 KiB
135 lines
2.8 KiB
/*
|
|
* resource cgroups
|
|
*
|
|
* Copyright 2007 OpenVZ SWsoft Inc
|
|
*
|
|
* Author: Pavel Emelianov <xemul@openvz.org>
|
|
*
|
|
*/
|
|
|
|
#include <linux/types.h>
|
|
#include <linux/parser.h>
|
|
#include <linux/fs.h>
|
|
#include <linux/res_counter.h>
|
|
#include <linux/uaccess.h>
|
|
|
|
void res_counter_init(struct res_counter *counter)
|
|
{
|
|
spin_lock_init(&counter->lock);
|
|
counter->limit = (unsigned long long)LLONG_MAX;
|
|
}
|
|
|
|
int res_counter_charge_locked(struct res_counter *counter, unsigned long val)
|
|
{
|
|
if (counter->usage + val > counter->limit) {
|
|
counter->failcnt++;
|
|
return -ENOMEM;
|
|
}
|
|
|
|
counter->usage += val;
|
|
return 0;
|
|
}
|
|
|
|
int res_counter_charge(struct res_counter *counter, unsigned long val)
|
|
{
|
|
int ret;
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&counter->lock, flags);
|
|
ret = res_counter_charge_locked(counter, val);
|
|
spin_unlock_irqrestore(&counter->lock, flags);
|
|
return ret;
|
|
}
|
|
|
|
void res_counter_uncharge_locked(struct res_counter *counter, unsigned long val)
|
|
{
|
|
if (WARN_ON(counter->usage < val))
|
|
val = counter->usage;
|
|
|
|
counter->usage -= val;
|
|
}
|
|
|
|
void res_counter_uncharge(struct res_counter *counter, unsigned long val)
|
|
{
|
|
unsigned long flags;
|
|
|
|
spin_lock_irqsave(&counter->lock, flags);
|
|
res_counter_uncharge_locked(counter, val);
|
|
spin_unlock_irqrestore(&counter->lock, flags);
|
|
}
|
|
|
|
|
|
static inline unsigned long long *
|
|
res_counter_member(struct res_counter *counter, int member)
|
|
{
|
|
switch (member) {
|
|
case RES_USAGE:
|
|
return &counter->usage;
|
|
case RES_LIMIT:
|
|
return &counter->limit;
|
|
case RES_FAILCNT:
|
|
return &counter->failcnt;
|
|
};
|
|
|
|
BUG();
|
|
return NULL;
|
|
}
|
|
|
|
ssize_t res_counter_read(struct res_counter *counter, int member,
|
|
const char __user *userbuf, size_t nbytes, loff_t *pos,
|
|
int (*read_strategy)(unsigned long long val, char *st_buf))
|
|
{
|
|
unsigned long long *val;
|
|
char buf[64], *s;
|
|
|
|
s = buf;
|
|
val = res_counter_member(counter, member);
|
|
if (read_strategy)
|
|
s += read_strategy(*val, s);
|
|
else
|
|
s += sprintf(s, "%llu\n", *val);
|
|
return simple_read_from_buffer((void __user *)userbuf, nbytes,
|
|
pos, buf, s - buf);
|
|
}
|
|
|
|
ssize_t res_counter_write(struct res_counter *counter, int member,
|
|
const char __user *userbuf, size_t nbytes, loff_t *pos,
|
|
int (*write_strategy)(char *st_buf, unsigned long long *val))
|
|
{
|
|
int ret;
|
|
char *buf, *end;
|
|
unsigned long flags;
|
|
unsigned long long tmp, *val;
|
|
|
|
buf = kmalloc(nbytes + 1, GFP_KERNEL);
|
|
ret = -ENOMEM;
|
|
if (buf == NULL)
|
|
goto out;
|
|
|
|
buf[nbytes] = '\0';
|
|
ret = -EFAULT;
|
|
if (copy_from_user(buf, userbuf, nbytes))
|
|
goto out_free;
|
|
|
|
ret = -EINVAL;
|
|
|
|
strstrip(buf);
|
|
if (write_strategy) {
|
|
if (write_strategy(buf, &tmp)) {
|
|
goto out_free;
|
|
}
|
|
} else {
|
|
tmp = simple_strtoull(buf, &end, 10);
|
|
if (*end != '\0')
|
|
goto out_free;
|
|
}
|
|
spin_lock_irqsave(&counter->lock, flags);
|
|
val = res_counter_member(counter, member);
|
|
*val = tmp;
|
|
spin_unlock_irqrestore(&counter->lock, flags);
|
|
ret = nbytes;
|
|
out_free:
|
|
kfree(buf);
|
|
out:
|
|
return ret;
|
|
}
|
|
|