4 * Copyright 2007 OpenVZ SWsoft Inc
6 * Author: Pavel Emelianov <xemul@openvz.org>
10 #include <linux/types.h>
11 #include <linux/parser.h>
13 #include <linux/res_counter.h>
14 #include <linux/uaccess.h>
17 void res_counter_init(struct res_counter *counter, struct res_counter *parent)
19 spin_lock_init(&counter->lock);
20 counter->limit = RES_COUNTER_MAX;
21 counter->soft_limit = RES_COUNTER_MAX;
22 counter->parent = parent;
25 int res_counter_charge_locked(struct res_counter *counter, unsigned long val,
30 if (counter->usage + val > counter->limit) {
37 counter->usage += val;
38 if (counter->usage > counter->max_usage)
39 counter->max_usage = counter->usage;
43 static int __res_counter_charge(struct res_counter *counter, unsigned long val,
44 struct res_counter **limit_fail_at, bool force)
48 struct res_counter *c, *u;
51 *limit_fail_at = NULL;
52 local_irq_save(flags);
53 for (c = counter; c != NULL; c = c->parent) {
55 r = res_counter_charge_locked(c, val, force);
56 spin_unlock(&c->lock);
65 if (ret < 0 && !force) {
66 for (u = counter; u != c; u = u->parent) {
68 res_counter_uncharge_locked(u, val);
69 spin_unlock(&u->lock);
72 local_irq_restore(flags);
77 int res_counter_charge(struct res_counter *counter, unsigned long val,
78 struct res_counter **limit_fail_at)
80 return __res_counter_charge(counter, val, limit_fail_at, false);
83 int res_counter_charge_nofail(struct res_counter *counter, unsigned long val,
84 struct res_counter **limit_fail_at)
86 return __res_counter_charge(counter, val, limit_fail_at, true);
89 u64 res_counter_uncharge_locked(struct res_counter *counter, unsigned long val)
91 if (WARN_ON(counter->usage < val))
94 counter->usage -= val;
95 return counter->usage;
98 u64 res_counter_uncharge_until(struct res_counter *counter,
99 struct res_counter *top,
103 struct res_counter *c;
106 local_irq_save(flags);
107 for (c = counter; c != top; c = c->parent) {
110 r = res_counter_uncharge_locked(c, val);
113 spin_unlock(&c->lock);
115 local_irq_restore(flags);
119 u64 res_counter_uncharge(struct res_counter *counter, unsigned long val)
121 return res_counter_uncharge_until(counter, NULL, val);
124 static inline unsigned long long *
125 res_counter_member(struct res_counter *counter, int member)
129 return &counter->usage;
131 return &counter->max_usage;
133 return &counter->limit;
135 return &counter->failcnt;
137 return &counter->soft_limit;
144 ssize_t res_counter_read(struct res_counter *counter, int member,
145 const char __user *userbuf, size_t nbytes, loff_t *pos,
146 int (*read_strategy)(unsigned long long val, char *st_buf))
148 unsigned long long *val;
152 val = res_counter_member(counter, member);
154 s += read_strategy(*val, s);
156 s += sprintf(s, "%llu\n", *val);
157 return simple_read_from_buffer((void __user *)userbuf, nbytes,
161 #if BITS_PER_LONG == 32
162 u64 res_counter_read_u64(struct res_counter *counter, int member)
167 spin_lock_irqsave(&counter->lock, flags);
168 ret = *res_counter_member(counter, member);
169 spin_unlock_irqrestore(&counter->lock, flags);
174 u64 res_counter_read_u64(struct res_counter *counter, int member)
176 return *res_counter_member(counter, member);
180 int res_counter_memparse_write_strategy(const char *buf,
181 unsigned long long *resp)
184 unsigned long long res;
186 /* return RES_COUNTER_MAX(unlimited) if "-1" is specified */
188 res = simple_strtoull(buf + 1, &end, 10);
189 if (res != 1 || *end != '\0')
191 *resp = RES_COUNTER_MAX;
195 res = memparse(buf, &end);
199 if (PAGE_ALIGN(res) >= res)
200 res = PAGE_ALIGN(res);
202 res = RES_COUNTER_MAX;