bsd/netinet/tcp_lro.h

   1 /*
   2  * Copyright (c) 2011 Apple Inc. All rights reserved.
   3  *
   4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
   5  *
   6  * This file contains Original Code and/or Modifications of Original Code
   7  * as defined in and that are subject to the Apple Public Source License
   8  * Version 2.0 (the 'License'). You may not use this file except in
   9  * compliance with the License. The rights granted to you under the License
  10  * may not be used to create, or enable the creation or redistribution of,
  11  * unlawful or unlicensed copies of an Apple operating system, or to
  12  * circumvent, violate, or enable the circumvention or violation of, any
  13  * terms of an Apple operating system software license agreement.
  14  *
  15  * Please obtain a copy of the License at
  16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
  17  *
  18  * The Original Code and all software distributed under the License are
  19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
  20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
  21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
  22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
  23  * Please see the License for the specific language governing rights and
  24  * limitations under the License.
  25  *
  26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
  27  */
  28
  29 #ifndef TCP_LRO_H_
  30 #define TCP_LRO_H_
  31
  32 #ifdef BSD_KERNEL_PRIVATE
  33
  34 #define TCP_LRO_NUM_FLOWS (16)  /* must be <= 255 for char lro_flow_map */
  35 #define TCP_LRO_FLOW_MAP  (1024)
  36
  37 struct lro_flow {
  38         struct mbuf             *lr_mhead;      /* coalesced mbuf chain head */
  39         struct mbuf             *lr_mtail;      /* coalesced mbuf chain tail */
  40         struct tcphdr           *lr_tcphdr;     /* ptr to TCP hdr in frame */
  41         u_int32_t               *lr_tsval;      /* address of tsval in frame */
  42         u_int32_t               *lr_tsecr;      /* tsecr field in TCP header */
  43         tcp_seq                 lr_seq;         /* next expected seq num */
  44         unsigned int            lr_len;         /* length of LRO frame */
  45         struct in_addr          lr_faddr;       /* foreign address */
  46         struct in_addr          lr_laddr;       /* local address */
  47         unsigned short int      lr_fport;       /* foreign port */
  48         unsigned short int      lr_lport;       /* local port */
  49         u_int32_t               lr_timestamp;   /* for ejecting the flow */
  50         unsigned short int      lr_hash_map;    /* back pointer to hash map */
  51         unsigned short int      lr_flags;       /* pad */
  52 } __attribute__((aligned(8)));
  53
  54 /* lr_flags - only 16 bits available */
  55 #define LRO_EJECT_REQ   0x1
  56
  57
  58 #define TCP_LRO_FLOW_UNINIT TCP_LRO_NUM_FLOWS+1
  59 #define TCP_LRO_FLOW_NOTFOUND TCP_LRO_FLOW_UNINIT
  60
  61 /* Max packets to be coalesced before pushing to app */
  62 #define LRO_MX_COALESCE_PKTS (8)
  63
  64 /*
  65  * Min num of bytes in a packet to trigger coalescing
  66  */
  67 #define LRO_MIN_COALESC_SZ  (1300)
  68
  69 /*
  70  * Max amount of time to wait before flushing flows in msecs.
  71  * Units are in msecs.
  72  * This number has been carefully chosen and should be altered with care.
  73  */
  74 #define LRO_MX_TIME_TO_BUFFER 10
  75
  76 /* similar to INP_PCBHASH */
  77 #define LRO_HASH(faddr, laddr, fport, lport, mask) \
  78         (((faddr) ^ ((laddr) >> 16) ^ ntohs((lport) ^ (fport))) & (mask))
  79 #endif
  80
  81 #endif /* TCP_LRO_H_ */