xref: /openbmc/linux/net/rxrpc/misc.c (revision aac5987a)
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  */
21 unsigned int rxrpc_max_backlog __read_mostly = 10;
22 
23 /*
24  * Maximum lifetime of a call (in mx).
25  */
26 unsigned int rxrpc_max_call_lifetime = 60 * 1000;
27 
28 /*
29  * How long to wait before scheduling ACK generation after seeing a
30  * packet with RXRPC_REQUEST_ACK set (in ms).
31  */
32 unsigned int rxrpc_requested_ack_delay = 1;
33 
34 /*
35  * How long to wait before scheduling an ACK with subtype DELAY (in ms).
36  *
37  * We use this when we've received new data packets.  If those packets aren't
38  * all consumed within this time we will send a DELAY ACK if an ACK was not
39  * requested to let the sender know it doesn't need to resend.
40  */
41 unsigned int rxrpc_soft_ack_delay = 1 * 1000;
42 
43 /*
44  * How long to wait before scheduling an ACK with subtype IDLE (in ms).
45  *
46  * We use this when we've consumed some previously soft-ACK'd packets when
47  * further packets aren't immediately received to decide when to send an IDLE
48  * ACK let the other end know that it can free up its Tx buffer space.
49  */
50 unsigned int rxrpc_idle_ack_delay = 0.5 * 1000;
51 
52 /*
53  * Receive window size in packets.  This indicates the maximum number of
54  * unconsumed received packets we're willing to retain in memory.  Once this
55  * limit is hit, we should generate an EXCEEDS_WINDOW ACK and discard further
56  * packets.
57  */
58 unsigned int rxrpc_rx_window_size = RXRPC_INIT_RX_WINDOW_SIZE;
59 #if (RXRPC_RXTX_BUFF_SIZE - 1) < RXRPC_INIT_RX_WINDOW_SIZE
60 #error Need to reduce RXRPC_INIT_RX_WINDOW_SIZE
61 #endif
62 
63 /*
64  * Maximum Rx MTU size.  This indicates to the sender the size of jumbo packet
65  * made by gluing normal packets together that we're willing to handle.
66  */
67 unsigned int rxrpc_rx_mtu = 5692;
68 
69 /*
70  * The maximum number of fragments in a received jumbo packet that we tell the
71  * sender that we're willing to handle.
72  */
73 unsigned int rxrpc_rx_jumbo_max = 4;
74 
75 /*
76  * Time till packet resend (in milliseconds).
77  */
78 unsigned int rxrpc_resend_timeout = 4 * 1000;
79 
80 const s8 rxrpc_ack_priority[] = {
81 	[0]				= 0,
82 	[RXRPC_ACK_DELAY]		= 1,
83 	[RXRPC_ACK_REQUESTED]		= 2,
84 	[RXRPC_ACK_IDLE]		= 3,
85 	[RXRPC_ACK_DUPLICATE]		= 4,
86 	[RXRPC_ACK_OUT_OF_SEQUENCE]	= 5,
87 	[RXRPC_ACK_EXCEEDS_WINDOW]	= 6,
88 	[RXRPC_ACK_NOSPACE]		= 7,
89 	[RXRPC_ACK_PING_RESPONSE]	= 8,
90 };
91