net/core/request_sock.c

   1 /*
   2  * NET          Generic infrastructure for Network protocols.
   3  *
   4  * Authors:     Arnaldo Carvalho de Melo <acme@conectiva.com.br>
   5  *
   6  *              From code originally in include/net/tcp.h
   7  *
   8  *              This program is free software; you can redistribute it and/or
   9  *              modify it under the terms of the GNU General Public License
  10  *              as published by the Free Software Foundation; either version
  11  *              2 of the License, or (at your option) any later version.
  12  */
  13
  14 #include <linux/module.h>
  15 #include <linux/random.h>
  16 #include <linux/slab.h>
  17 #include <linux/string.h>
  18
  19 #include <net/request_sock.h>
  20
  21 int reqsk_queue_alloc(struct request_sock_queue *queue,
  22                       const int nr_table_entries)
  23 {
  24         const int lopt_size = sizeof(struct listen_sock) +
  25                               nr_table_entries * sizeof(struct request_sock *);
  26         struct listen_sock *lopt = kmalloc(lopt_size, GFP_KERNEL);
  27
  28         if (lopt == NULL)
  29                 return -ENOMEM;
  30
  31         memset(lopt, 0, lopt_size);
  32
  33         for (lopt->max_qlen_log = 6;
  34              (1 << lopt->max_qlen_log) < sysctl_max_syn_backlog;
  35              lopt->max_qlen_log++);
  36
  37         get_random_bytes(&lopt->hash_rnd, sizeof(lopt->hash_rnd));
  38         rwlock_init(&queue->syn_wait_lock);
  39         queue->rskq_accept_head = queue->rskq_accept_head = NULL;
  40
  41         write_lock_bh(&queue->syn_wait_lock);
  42         queue->listen_opt = lopt;
  43         write_unlock_bh(&queue->syn_wait_lock);
  44
  45         return 0;
  46 }
  47
  48 EXPORT_SYMBOL(reqsk_queue_alloc);