net/core/sysctl_net_core.c

   1 /* -*- linux-c -*-
   2  * sysctl_net_core.c: sysctl interface to net core subsystem.
   3  *
   4  * Begun April 1, 1996, Mike Shaver.
   5  * Added /proc/sys/net/core directory entry (empty =) ). [MS]
   6  */
   7
   8 #include <linux/mm.h>
   9 #include <linux/sysctl.h>
  10 #include <linux/module.h>
  11 #include <linux/socket.h>
  12 #include <linux/netdevice.h>
  13 #include <linux/ratelimit.h>
  14 #include <linux/vmalloc.h>
  15 #include <linux/init.h>
  16 #include <linux/slab.h>
  17
  18 #include <net/ip.h>
  19 #include <net/sock.h>
  20
  21 #ifdef CONFIG_RPS
  22 static int rps_sock_flow_sysctl(ctl_table *table, int write,
  23                                 void __user *buffer, size_t *lenp, loff_t *ppos)
  24 {
  25         unsigned int orig_size, size;
  26         int ret, i;
  27         ctl_table tmp = {
  28                 .data = &size,
  29                 .maxlen = sizeof(size),
  30                 .mode = table->mode
  31         };
  32         struct rps_sock_flow_table *orig_sock_table, *sock_table;
  33         static DEFINE_MUTEX(sock_flow_mutex);
  34
  35         mutex_lock(&sock_flow_mutex);
  36
  37         orig_sock_table = rps_sock_flow_table;
  38         size = orig_size = orig_sock_table ? orig_sock_table->mask + 1 : 0;
  39
  40         ret = proc_dointvec(&tmp, write, buffer, lenp, ppos);
  41
  42         if (write) {
  43                 if (size) {
  44                         if (size > 1<<30) {
  45                                 /* Enforce limit to prevent overflow */
  46                                 mutex_unlock(&sock_flow_mutex);
  47                                 return -EINVAL;
  48                         }
  49                         size = roundup_pow_of_two(size);
  50                         if (size != orig_size) {
  51                                 sock_table =
  52                                     vmalloc(RPS_SOCK_FLOW_TABLE_SIZE(size));
  53                                 if (!sock_table) {
  54                                         mutex_unlock(&sock_flow_mutex);
  55                                         return -ENOMEM;
  56                                 }
  57
  58                                 sock_table->mask = size - 1;
  59                         } else
  60                                 sock_table = orig_sock_table;
  61
  62                         for (i = 0; i < size; i++)
  63                                 sock_table->ents[i] = RPS_NO_CPU;
  64                 } else
  65                         sock_table = NULL;
  66
  67                 if (sock_table != orig_sock_table) {
  68                         rcu_assign_pointer(rps_sock_flow_table, sock_table);
  69                         synchronize_rcu();
  70                         vfree(orig_sock_table);
  71                 }
  72         }
  73
  74         mutex_unlock(&sock_flow_mutex);
  75
  76         return ret;
  77 }
  78 #endif /* CONFIG_RPS */
  79
  80 static struct ctl_table net_core_table[] = {
  81 #ifdef CONFIG_NET
  82         {
  83                 .procname       = "wmem_max",
  84                 .data           = &sysctl_wmem_max,
  85                 .maxlen         = sizeof(int),
  86                 .mode           = 0644,
  87                 .proc_handler   = proc_dointvec
  88         },
  89         {
  90                 .procname       = "rmem_max",
  91                 .data           = &sysctl_rmem_max,
  92                 .maxlen         = sizeof(int),
  93                 .mode           = 0644,
  94                 .proc_handler   = proc_dointvec
  95         },
  96         {
  97                 .procname       = "wmem_default",
  98                 .data           = &sysctl_wmem_default,
  99                 .maxlen         = sizeof(int),
 100                 .mode           = 0644,
 101                 .proc_handler   = proc_dointvec
 102         },
 103         {
 104                 .procname       = "rmem_default",
 105                 .data           = &sysctl_rmem_default,
 106                 .maxlen         = sizeof(int),
 107                 .mode           = 0644,
 108                 .proc_handler   = proc_dointvec
 109         },
 110         {
 111                 .procname       = "dev_weight",
 112                 .data           = &weight_p,
 113                 .maxlen         = sizeof(int),
 114                 .mode           = 0644,
 115                 .proc_handler   = proc_dointvec
 116         },
 117         {
 118                 .procname       = "netdev_max_backlog",
 119                 .data           = &netdev_max_backlog,
 120                 .maxlen         = sizeof(int),
 121                 .mode           = 0644,
 122                 .proc_handler   = proc_dointvec
 123         },
 124         {
 125                 .procname       = "message_cost",
 126                 .data           = &net_ratelimit_state.interval,
 127                 .maxlen         = sizeof(int),
 128                 .mode           = 0644,
 129                 .proc_handler   = proc_dointvec_jiffies,
 130         },
 131         {
 132                 .procname       = "message_burst",
 133                 .data           = &net_ratelimit_state.burst,
 134                 .maxlen         = sizeof(int),
 135                 .mode           = 0644,
 136                 .proc_handler   = proc_dointvec,
 137         },
 138         {
 139                 .procname       = "optmem_max",
 140                 .data           = &sysctl_optmem_max,
 141                 .maxlen         = sizeof(int),
 142                 .mode           = 0644,
 143                 .proc_handler   = proc_dointvec
 144         },
 145 #ifdef CONFIG_RPS
 146         {
 147                 .procname       = "rps_sock_flow_entries",
 148                 .maxlen         = sizeof(int),
 149                 .mode           = 0644,
 150                 .proc_handler   = rps_sock_flow_sysctl
 151         },
 152 #endif
 153 #endif /* CONFIG_NET */
 154         {
 155                 .procname       = "netdev_budget",
 156                 .data           = &netdev_budget,
 157                 .maxlen         = sizeof(int),
 158                 .mode           = 0644,
 159                 .proc_handler   = proc_dointvec
 160         },
 161         {
 162                 .procname       = "warnings",
 163                 .data           = &net_msg_warn,
 164                 .maxlen         = sizeof(int),
 165                 .mode           = 0644,
 166                 .proc_handler   = proc_dointvec
 167         },
 168         { }
 169 };
 170
 171 static struct ctl_table netns_core_table[] = {
 172         {
 173                 .procname       = "somaxconn",
 174                 .data           = &init_net.core.sysctl_somaxconn,
 175                 .maxlen         = sizeof(int),
 176                 .mode           = 0644,
 177                 .proc_handler   = proc_dointvec
 178         },
 179         { }
 180 };
 181
 182 __net_initdata struct ctl_path net_core_path[] = {
 183         { .procname = "net", },
 184         { .procname = "core", },
 185         { },
 186 };
 187
 188 static __net_init int sysctl_core_net_init(struct net *net)
 189 {
 190         struct ctl_table *tbl;
 191
 192         net->core.sysctl_somaxconn = SOMAXCONN;
 193
 194         tbl = netns_core_table;
 195         if (!net_eq(net, &init_net)) {
 196                 tbl = kmemdup(tbl, sizeof(netns_core_table), GFP_KERNEL);
 197                 if (tbl == NULL)
 198                         goto err_dup;
 199
 200                 tbl[0].data = &net->core.sysctl_somaxconn;
 201         }
 202
 203         net->core.sysctl_hdr = register_net_sysctl_table(net,
 204                         net_core_path, tbl);
 205         if (net->core.sysctl_hdr == NULL)
 206                 goto err_reg;
 207
 208         return 0;
 209
 210 err_reg:
 211         if (tbl != netns_core_table)
 212                 kfree(tbl);
 213 err_dup:
 214         return -ENOMEM;
 215 }
 216
 217 static __net_exit void sysctl_core_net_exit(struct net *net)
 218 {
 219         struct ctl_table *tbl;
 220
 221         tbl = net->core.sysctl_hdr->ctl_table_arg;
 222         unregister_net_sysctl_table(net->core.sysctl_hdr);
 223         BUG_ON(tbl == netns_core_table);
 224         kfree(tbl);
 225 }
 226
 227 static __net_initdata struct pernet_operations sysctl_core_ops = {
 228         .init = sysctl_core_net_init,
 229         .exit = sysctl_core_net_exit,
 230 };
 231
 232 static __init int sysctl_core_init(void)
 233 {
 234         static struct ctl_table empty[1];
 235
 236         register_sysctl_paths(net_core_path, empty);
 237         register_net_sysctl_rotable(net_core_path, net_core_table);
 238         return register_pernet_subsys(&sysctl_core_ops);
 239 }
 240
 241 fs_initcall(sysctl_core_init);