1 #define KMSG_COMPONENT "IPVS"
2 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt
3
4 #include <linux/module.h>
5 #include <linux/spinlock.h>
6 #include <linux/interrupt.h>
7 #include <asm/string.h>
8 #include <linux/kmod.h>
9 #include <linux/sysctl.h>
10
11 #include <net/ip_vs.h>
12
13 /* IPVS pe list */
14 static LIST_HEAD(ip_vs_pe);
15
16 /* lock for service table */
17 static DEFINE_SPINLOCK(ip_vs_pe_lock);
18
19 /* Bind a service with a pe */
ip_vs_bind_pe(struct ip_vs_service * svc,struct ip_vs_pe * pe)20 void ip_vs_bind_pe(struct ip_vs_service *svc, struct ip_vs_pe *pe)
21 {
22 svc->pe = pe;
23 }
24
25 /* Unbind a service from its pe */
ip_vs_unbind_pe(struct ip_vs_service * svc)26 void ip_vs_unbind_pe(struct ip_vs_service *svc)
27 {
28 svc->pe = NULL;
29 }
30
31 /* Get pe in the pe list by name */
__ip_vs_pe_getbyname(const char * pe_name)32 struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name)
33 {
34 struct ip_vs_pe *pe;
35
36 IP_VS_DBG(10, "%s(): pe_name \"%s\"\n", __func__,
37 pe_name);
38
39 spin_lock_bh(&ip_vs_pe_lock);
40
41 list_for_each_entry(pe, &ip_vs_pe, n_list) {
42 /* Test and get the modules atomically */
43 if (pe->module &&
44 !try_module_get(pe->module)) {
45 /* This pe is just deleted */
46 continue;
47 }
48 if (strcmp(pe_name, pe->name)==0) {
49 /* HIT */
50 spin_unlock_bh(&ip_vs_pe_lock);
51 return pe;
52 }
53 if (pe->module)
54 module_put(pe->module);
55 }
56
57 spin_unlock_bh(&ip_vs_pe_lock);
58 return NULL;
59 }
60
61 /* Lookup pe and try to load it if it doesn't exist */
ip_vs_pe_getbyname(const char * name)62 struct ip_vs_pe *ip_vs_pe_getbyname(const char *name)
63 {
64 struct ip_vs_pe *pe;
65
66 /* Search for the pe by name */
67 pe = __ip_vs_pe_getbyname(name);
68
69 /* If pe not found, load the module and search again */
70 if (!pe) {
71 request_module("ip_vs_pe_%s", name);
72 pe = __ip_vs_pe_getbyname(name);
73 }
74
75 return pe;
76 }
77
78 /* Register a pe in the pe list */
register_ip_vs_pe(struct ip_vs_pe * pe)79 int register_ip_vs_pe(struct ip_vs_pe *pe)
80 {
81 struct ip_vs_pe *tmp;
82
83 /* increase the module use count */
84 ip_vs_use_count_inc();
85
86 spin_lock_bh(&ip_vs_pe_lock);
87
88 if (!list_empty(&pe->n_list)) {
89 spin_unlock_bh(&ip_vs_pe_lock);
90 ip_vs_use_count_dec();
91 pr_err("%s(): [%s] pe already linked\n",
92 __func__, pe->name);
93 return -EINVAL;
94 }
95
96 /* Make sure that the pe with this name doesn't exist
97 * in the pe list.
98 */
99 list_for_each_entry(tmp, &ip_vs_pe, n_list) {
100 if (strcmp(tmp->name, pe->name) == 0) {
101 spin_unlock_bh(&ip_vs_pe_lock);
102 ip_vs_use_count_dec();
103 pr_err("%s(): [%s] pe already existed "
104 "in the system\n", __func__, pe->name);
105 return -EINVAL;
106 }
107 }
108 /* Add it into the d-linked pe list */
109 list_add(&pe->n_list, &ip_vs_pe);
110 spin_unlock_bh(&ip_vs_pe_lock);
111
112 pr_info("[%s] pe registered.\n", pe->name);
113
114 return 0;
115 }
116 EXPORT_SYMBOL_GPL(register_ip_vs_pe);
117
118 /* Unregister a pe from the pe list */
unregister_ip_vs_pe(struct ip_vs_pe * pe)119 int unregister_ip_vs_pe(struct ip_vs_pe *pe)
120 {
121 spin_lock_bh(&ip_vs_pe_lock);
122 if (list_empty(&pe->n_list)) {
123 spin_unlock_bh(&ip_vs_pe_lock);
124 pr_err("%s(): [%s] pe is not in the list. failed\n",
125 __func__, pe->name);
126 return -EINVAL;
127 }
128
129 /* Remove it from the d-linked pe list */
130 list_del(&pe->n_list);
131 spin_unlock_bh(&ip_vs_pe_lock);
132
133 /* decrease the module use count */
134 ip_vs_use_count_dec();
135
136 pr_info("[%s] pe unregistered.\n", pe->name);
137
138 return 0;
139 }
140 EXPORT_SYMBOL_GPL(unregister_ip_vs_pe);
141