Simon Horman | 8be67a6 | 2010-08-22 21:37:54 +0900 | [diff] [blame] | 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 */ |
| 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 */ |
| 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 */ |
Hans Schillstrom | fe5e7a1 | 2010-11-19 14:25:12 +0100 | [diff] [blame] | 32 | struct ip_vs_pe *__ip_vs_pe_getbyname(const char *pe_name) |
Simon Horman | 8be67a6 | 2010-08-22 21:37:54 +0900 | [diff] [blame] | 33 | { |
| 34 | struct ip_vs_pe *pe; |
| 35 | |
Hans Schillstrom | fe5e7a1 | 2010-11-19 14:25:12 +0100 | [diff] [blame] | 36 | IP_VS_DBG(10, "%s(): pe_name \"%s\"\n", __func__, |
Simon Horman | 8be67a6 | 2010-08-22 21:37:54 +0900 | [diff] [blame] | 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 */ |
Simon Horman | e9e5eee | 2010-11-08 20:05:57 +0900 | [diff] [blame] | 62 | struct ip_vs_pe *ip_vs_pe_getbyname(const char *name) |
Simon Horman | 8be67a6 | 2010-08-22 21:37:54 +0900 | [diff] [blame] | 63 | { |
| 64 | struct ip_vs_pe *pe; |
| 65 | |
| 66 | /* Search for the pe by name */ |
Simon Horman | e9e5eee | 2010-11-08 20:05:57 +0900 | [diff] [blame] | 67 | pe = __ip_vs_pe_getbyname(name); |
Simon Horman | 8be67a6 | 2010-08-22 21:37:54 +0900 | [diff] [blame] | 68 | |
| 69 | /* If pe not found, load the module and search again */ |
| 70 | if (!pe) { |
| 71 | request_module("ip_vs_pe_%s", name); |
Simon Horman | e9e5eee | 2010-11-08 20:05:57 +0900 | [diff] [blame] | 72 | pe = __ip_vs_pe_getbyname(name); |
Simon Horman | 8be67a6 | 2010-08-22 21:37:54 +0900 | [diff] [blame] | 73 | } |
| 74 | |
| 75 | return pe; |
| 76 | } |
| 77 | |
Simon Horman | 8be67a6 | 2010-08-22 21:37:54 +0900 | [diff] [blame] | 78 | /* Register a pe in the pe list */ |
| 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 */ |
| 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); |