LXR linux/net/rxrpc/misc.c

   1/* Miscellaneous bits
   2 *
   3 * Copyright (C) 2016 Red Hat, Inc. All Rights Reserved.
   4 * Written by David Howells (dhowells@redhat.com)
   5 *
   6 * This program is free software; you can redistribute it and/or
   7 * modify it under the terms of the GNU General Public Licence
   8 * as published by the Free Software Foundation; either version
   9 * 2 of the Licence, or (at your option) any later version.
  10 */
  11
  12#include <linux/kernel.h>
  13#include <net/sock.h>
  14#include <net/af_rxrpc.h>
  15#include "ar-internal.h"
  16
  17/*
  18 * The maximum listening backlog queue size that may be set on a socket by
  19 * listen().
  20 */
  21unsigned int rxrpc_max_backlog __read_mostly = 10;
  22
  23/*
  24 * How long to wait before scheduling ACK generation after seeing a
  25 * packet with RXRPC_REQUEST_ACK set (in jiffies).
  26 */
  27unsigned long rxrpc_requested_ack_delay = 1;
  28
  29/*
  30 * How long to wait before scheduling an ACK with subtype DELAY (in jiffies).
  31 *
  32 * We use this when we've received new data packets.  If those packets aren't
  33 * all consumed within this time we will send a DELAY ACK if an ACK was not
  34 * requested to let the sender know it doesn't need to resend.
  35 */
  36unsigned long rxrpc_soft_ack_delay = HZ;
  37
  38/*
  39 * How long to wait before scheduling an ACK with subtype IDLE (in jiffies).
  40 *
  41 * We use this when we've consumed some previously soft-ACK'd packets when
  42 * further packets aren't immediately received to decide when to send an IDLE
  43 * ACK let the other end know that it can free up its Tx buffer space.
  44 */
  45unsigned long rxrpc_idle_ack_delay = HZ / 2;
  46
  47/*
  48 * Receive window size in packets.  This indicates the maximum number of
  49 * unconsumed received packets we're willing to retain in memory.  Once this
  50 * limit is hit, we should generate an EXCEEDS_WINDOW ACK and discard further
  51 * packets.
  52 */
  53unsigned int rxrpc_rx_window_size = RXRPC_INIT_RX_WINDOW_SIZE;
  54#if (RXRPC_RXTX_BUFF_SIZE - 1) < RXRPC_INIT_RX_WINDOW_SIZE
  55#error Need to reduce RXRPC_INIT_RX_WINDOW_SIZE
  56#endif
  57
  58/*
  59 * Maximum Rx MTU size.  This indicates to the sender the size of jumbo packet
  60 * made by gluing normal packets together that we're willing to handle.
  61 */
  62unsigned int rxrpc_rx_mtu = 5692;
  63
  64/*
  65 * The maximum number of fragments in a received jumbo packet that we tell the
  66 * sender that we're willing to handle.
  67 */
  68unsigned int rxrpc_rx_jumbo_max = 4;
  69
  70/*
  71 * Time till packet resend (in milliseconds).
  72 */
  73unsigned long rxrpc_resend_timeout = 4 * HZ;
  74
  75const s8 rxrpc_ack_priority[] = {
  76        [0]                             = 0,
  77        [RXRPC_ACK_DELAY]               = 1,
  78        [RXRPC_ACK_REQUESTED]           = 2,
  79        [RXRPC_ACK_IDLE]                = 3,
  80        [RXRPC_ACK_DUPLICATE]           = 4,
  81        [RXRPC_ACK_OUT_OF_SEQUENCE]     = 5,
  82        [RXRPC_ACK_EXCEEDS_WINDOW]      = 6,
  83        [RXRPC_ACK_NOSPACE]             = 7,
  84        [RXRPC_ACK_PING_RESPONSE]       = 8,
  85};
  86