Commit | Line | Data |
---|---|---|
e552b661 PE |
1 | /* |
2 | * resource cgroups | |
3 | * | |
4 | * Copyright 2007 OpenVZ SWsoft Inc | |
5 | * | |
6 | * Author: Pavel Emelianov <xemul@openvz.org> | |
7 | * | |
8 | */ | |
9 | ||
10 | #include <linux/types.h> | |
11 | #include <linux/parser.h> | |
12 | #include <linux/fs.h> | |
1aeb272c | 13 | #include <linux/slab.h> |
e552b661 PE |
14 | #include <linux/res_counter.h> |
15 | #include <linux/uaccess.h> | |
16 | ||
17 | void res_counter_init(struct res_counter *counter) | |
18 | { | |
19 | spin_lock_init(&counter->lock); | |
0eea1030 | 20 | counter->limit = (unsigned long long)LLONG_MAX; |
e552b661 PE |
21 | } |
22 | ||
23 | int res_counter_charge_locked(struct res_counter *counter, unsigned long val) | |
24 | { | |
25 | if (counter->usage + val > counter->limit) { | |
26 | counter->failcnt++; | |
27 | return -ENOMEM; | |
28 | } | |
29 | ||
30 | counter->usage += val; | |
c84872e1 PE |
31 | if (counter->usage > counter->max_usage) |
32 | counter->max_usage = counter->usage; | |
e552b661 PE |
33 | return 0; |
34 | } | |
35 | ||
36 | int res_counter_charge(struct res_counter *counter, unsigned long val) | |
37 | { | |
38 | int ret; | |
39 | unsigned long flags; | |
40 | ||
41 | spin_lock_irqsave(&counter->lock, flags); | |
42 | ret = res_counter_charge_locked(counter, val); | |
43 | spin_unlock_irqrestore(&counter->lock, flags); | |
44 | return ret; | |
45 | } | |
46 | ||
47 | void res_counter_uncharge_locked(struct res_counter *counter, unsigned long val) | |
48 | { | |
49 | if (WARN_ON(counter->usage < val)) | |
50 | val = counter->usage; | |
51 | ||
52 | counter->usage -= val; | |
53 | } | |
54 | ||
55 | void res_counter_uncharge(struct res_counter *counter, unsigned long val) | |
56 | { | |
57 | unsigned long flags; | |
58 | ||
59 | spin_lock_irqsave(&counter->lock, flags); | |
60 | res_counter_uncharge_locked(counter, val); | |
61 | spin_unlock_irqrestore(&counter->lock, flags); | |
62 | } | |
63 | ||
64 | ||
0eea1030 BS |
65 | static inline unsigned long long * |
66 | res_counter_member(struct res_counter *counter, int member) | |
e552b661 PE |
67 | { |
68 | switch (member) { | |
69 | case RES_USAGE: | |
70 | return &counter->usage; | |
c84872e1 PE |
71 | case RES_MAX_USAGE: |
72 | return &counter->max_usage; | |
e552b661 PE |
73 | case RES_LIMIT: |
74 | return &counter->limit; | |
75 | case RES_FAILCNT: | |
76 | return &counter->failcnt; | |
77 | }; | |
78 | ||
79 | BUG(); | |
80 | return NULL; | |
81 | } | |
82 | ||
83 | ssize_t res_counter_read(struct res_counter *counter, int member, | |
0eea1030 BS |
84 | const char __user *userbuf, size_t nbytes, loff_t *pos, |
85 | int (*read_strategy)(unsigned long long val, char *st_buf)) | |
e552b661 | 86 | { |
0eea1030 | 87 | unsigned long long *val; |
e552b661 PE |
88 | char buf[64], *s; |
89 | ||
90 | s = buf; | |
91 | val = res_counter_member(counter, member); | |
0eea1030 BS |
92 | if (read_strategy) |
93 | s += read_strategy(*val, s); | |
94 | else | |
95 | s += sprintf(s, "%llu\n", *val); | |
e552b661 PE |
96 | return simple_read_from_buffer((void __user *)userbuf, nbytes, |
97 | pos, buf, s - buf); | |
98 | } | |
99 | ||
2c7eabf3 PM |
100 | u64 res_counter_read_u64(struct res_counter *counter, int member) |
101 | { | |
102 | return *res_counter_member(counter, member); | |
103 | } | |
104 | ||
e552b661 | 105 | ssize_t res_counter_write(struct res_counter *counter, int member, |
0eea1030 BS |
106 | const char __user *userbuf, size_t nbytes, loff_t *pos, |
107 | int (*write_strategy)(char *st_buf, unsigned long long *val)) | |
e552b661 PE |
108 | { |
109 | int ret; | |
110 | char *buf, *end; | |
0eea1030 BS |
111 | unsigned long flags; |
112 | unsigned long long tmp, *val; | |
e552b661 PE |
113 | |
114 | buf = kmalloc(nbytes + 1, GFP_KERNEL); | |
115 | ret = -ENOMEM; | |
116 | if (buf == NULL) | |
117 | goto out; | |
118 | ||
119 | buf[nbytes] = '\0'; | |
120 | ret = -EFAULT; | |
121 | if (copy_from_user(buf, userbuf, nbytes)) | |
122 | goto out_free; | |
123 | ||
124 | ret = -EINVAL; | |
e552b661 | 125 | |
fb78922c | 126 | strstrip(buf); |
0eea1030 BS |
127 | if (write_strategy) { |
128 | if (write_strategy(buf, &tmp)) { | |
129 | goto out_free; | |
130 | } | |
131 | } else { | |
132 | tmp = simple_strtoull(buf, &end, 10); | |
133 | if (*end != '\0') | |
134 | goto out_free; | |
135 | } | |
136 | spin_lock_irqsave(&counter->lock, flags); | |
e552b661 PE |
137 | val = res_counter_member(counter, member); |
138 | *val = tmp; | |
0eea1030 | 139 | spin_unlock_irqrestore(&counter->lock, flags); |
e552b661 PE |
140 | ret = nbytes; |
141 | out_free: | |
142 | kfree(buf); | |
143 | out: | |
144 | return ret; | |
145 | } |