drivers/infiniband/core/ud_header.c - maze/linux - Git at Google

 /*
  * Copyright (c) 2004 Topspin Corporation.  All rights reserved.
  * Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
  *
  * This software is available to you under a choice of one of two
  * licenses.  You may choose to be licensed under the terms of the GNU
  * General Public License (GPL) Version 2, available from the file
  * COPYING in the main directory of this source tree, or the
  * OpenIB.org BSD license below:
  *
  *     Redistribution and use in source and binary forms, with or
  *     without modification, are permitted provided that the following
  *     conditions are met:
  *
  *      - Redistributions of source code must retain the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer.
  *
  *      - Redistributions in binary form must reproduce the above
  *        copyright notice, this list of conditions and the following
  *        disclaimer in the documentation and/or other materials
  *        provided with the distribution.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  *
  * $Id: ud_header.c 1349 2004-12-16 21:09:43Z roland $
  */

 #include <linux/errno.h>
 #include <linux/string.h>

 #include <rdma/ib_pack.h>

 #define STRUCT_FIELD(header, field) \
 	.struct_offset_bytes = offsetof(struct ib_unpacked_ ## header, field),      \
 	.struct_size_bytes   = sizeof ((struct ib_unpacked_ ## header *) 0)->field, \
 	.field_name          = #header ":" #field

 static const struct ib_field lrh_table[]  = {
 	{ STRUCT_FIELD(lrh, virtual_lane),
 	  .offset_words = 0,
 	  .offset_bits  = 0,
 	  .size_bits    = 4 },
 	{ STRUCT_FIELD(lrh, link_version),
 	  .offset_words = 0,
 	  .offset_bits  = 4,
 	  .size_bits    = 4 },
 	{ STRUCT_FIELD(lrh, service_level),
 	  .offset_words = 0,
 	  .offset_bits  = 8,
 	  .size_bits    = 4 },
 	{ RESERVED,
 	  .offset_words = 0,
 	  .offset_bits  = 12,
 	  .size_bits    = 2 },
 	{ STRUCT_FIELD(lrh, link_next_header),
 	  .offset_words = 0,
 	  .offset_bits  = 14,
 	  .size_bits    = 2 },
 	{ STRUCT_FIELD(lrh, destination_lid),
 	  .offset_words = 0,
 	  .offset_bits  = 16,
 	  .size_bits    = 16 },
 	{ RESERVED,
 	  .offset_words = 1,
 	  .offset_bits  = 0,
 	  .size_bits    = 5 },
 	{ STRUCT_FIELD(lrh, packet_length),
 	  .offset_words = 1,
 	  .offset_bits  = 5,
 	  .size_bits    = 11 },
 	{ STRUCT_FIELD(lrh, source_lid),
 	  .offset_words = 1,
 	  .offset_bits  = 16,
 	  .size_bits    = 16 }
 };

 static const struct ib_field grh_table[]  = {
 	{ STRUCT_FIELD(grh, ip_version),
 	  .offset_words = 0,
 	  .offset_bits  = 0,
 	  .size_bits    = 4 },
 	{ STRUCT_FIELD(grh, traffic_class),
 	  .offset_words = 0,
 	  .offset_bits  = 4,
 	  .size_bits    = 8 },
 	{ STRUCT_FIELD(grh, flow_label),
 	  .offset_words = 0,
 	  .offset_bits  = 12,
 	  .size_bits    = 20 },
 	{ STRUCT_FIELD(grh, payload_length),
 	  .offset_words = 1,
 	  .offset_bits  = 0,
 	  .size_bits    = 16 },
 	{ STRUCT_FIELD(grh, next_header),
 	  .offset_words = 1,
 	  .offset_bits  = 16,
 	  .size_bits    = 8 },
 	{ STRUCT_FIELD(grh, hop_limit),
 	  .offset_words = 1,
 	  .offset_bits  = 24,
 	  .size_bits    = 8 },
 	{ STRUCT_FIELD(grh, source_gid),
 	  .offset_words = 2,
 	  .offset_bits  = 0,
 	  .size_bits    = 128 },
 	{ STRUCT_FIELD(grh, destination_gid),
 	  .offset_words = 6,
 	  .offset_bits  = 0,
 	  .size_bits    = 128 }
 };

 static const struct ib_field bth_table[]  = {
 	{ STRUCT_FIELD(bth, opcode),
 	  .offset_words = 0,
 	  .offset_bits  = 0,
 	  .size_bits    = 8 },
 	{ STRUCT_FIELD(bth, solicited_event),
 	  .offset_words = 0,
 	  .offset_bits  = 8,
 	  .size_bits    = 1 },
 	{ STRUCT_FIELD(bth, mig_req),
 	  .offset_words = 0,
 	  .offset_bits  = 9,
 	  .size_bits    = 1 },
 	{ STRUCT_FIELD(bth, pad_count),
 	  .offset_words = 0,
 	  .offset_bits  = 10,
 	  .size_bits    = 2 },
 	{ STRUCT_FIELD(bth, transport_header_version),
 	  .offset_words = 0,
 	  .offset_bits  = 12,
 	  .size_bits    = 4 },
 	{ STRUCT_FIELD(bth, pkey),
 	  .offset_words = 0,
 	  .offset_bits  = 16,
 	  .size_bits    = 16 },
 	{ RESERVED,
 	  .offset_words = 1,
 	  .offset_bits  = 0,
 	  .size_bits    = 8 },
 	{ STRUCT_FIELD(bth, destination_qpn),
 	  .offset_words = 1,
 	  .offset_bits  = 8,
 	  .size_bits    = 24 },
 	{ STRUCT_FIELD(bth, ack_req),
 	  .offset_words = 2,
 	  .offset_bits  = 0,
 	  .size_bits    = 1 },
 	{ RESERVED,
 	  .offset_words = 2,
 	  .offset_bits  = 1,
 	  .size_bits    = 7 },
 	{ STRUCT_FIELD(bth, psn),
 	  .offset_words = 2,
 	  .offset_bits  = 8,
 	  .size_bits    = 24 }
 };

 static const struct ib_field deth_table[] = {
 	{ STRUCT_FIELD(deth, qkey),
 	  .offset_words = 0,
 	  .offset_bits  = 0,
 	  .size_bits    = 32 },
 	{ RESERVED,
 	  .offset_words = 1,
 	  .offset_bits  = 0,
 	  .size_bits    = 8 },
 	{ STRUCT_FIELD(deth, source_qpn),
 	  .offset_words = 1,
 	  .offset_bits  = 8,
 	  .size_bits    = 24 }
 };

 /**
  * ib_ud_header_init - Initialize UD header structure
  * @payload_bytes:Length of packet payload
  * @grh_present:GRH flag (if non-zero, GRH will be included)
  * @header:Structure to initialize
  *
  * ib_ud_header_init() initializes the lrh.link_version, lrh.link_next_header,
  * lrh.packet_length, grh.ip_version, grh.payload_length,
  * grh.next_header, bth.opcode, bth.pad_count and
  * bth.transport_header_version fields of a &struct ib_ud_header given
  * the payload length and whether a GRH will be included.
  */
 void ib_ud_header_init(int     		    payload_bytes,
 		       int    		    grh_present,
 		       struct ib_ud_header *header)
 {
 	int header_len;
 	u16 packet_length;

 	memset(header, 0, sizeof *header);

 	header_len =
 		IB_LRH_BYTES  +
 		IB_BTH_BYTES  +
 		IB_DETH_BYTES;
 	if (grh_present) {
 		header_len += IB_GRH_BYTES;
 	}

 	header->lrh.link_version     = 0;
 	header->lrh.link_next_header =
 		grh_present ? IB_LNH_IBA_GLOBAL : IB_LNH_IBA_LOCAL;
 	packet_length		     = (IB_LRH_BYTES     +
 					IB_BTH_BYTES     +
 					IB_DETH_BYTES    +
 					payload_bytes    +
 					4                + /* ICRC     */
 					3) / 4;            /* round up */

 	header->grh_present          = grh_present;
 	if (grh_present) {
 		packet_length		   += IB_GRH_BYTES / 4;
 		header->grh.ip_version      = 6;
 		header->grh.payload_length  =
 			cpu_to_be16((IB_BTH_BYTES     +
 				     IB_DETH_BYTES    +
 				     payload_bytes    +
 				     4                + /* ICRC     */
 				     3) & ~3);          /* round up */
 		header->grh.next_header     = 0x1b;
 	}

 	header->lrh.packet_length = cpu_to_be16(packet_length);

 	if (header->immediate_present)
 		header->bth.opcode           = IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE;
 	else
 		header->bth.opcode           = IB_OPCODE_UD_SEND_ONLY;
 	header->bth.pad_count                = (4 - payload_bytes) & 3;
 	header->bth.transport_header_version = 0;
 }
 EXPORT_SYMBOL(ib_ud_header_init);

 /**
  * ib_ud_header_pack - Pack UD header struct into wire format
  * @header:UD header struct
  * @buf:Buffer to pack into
  *
  * ib_ud_header_pack() packs the UD header structure @header into wire
  * format in the buffer @buf.
  */
 int ib_ud_header_pack(struct ib_ud_header *header,
 		      void                *buf)
 {
 	int len = 0;

 	ib_pack(lrh_table, ARRAY_SIZE(lrh_table),
 		&header->lrh, buf);
 	len += IB_LRH_BYTES;

 	if (header->grh_present) {
 		ib_pack(grh_table, ARRAY_SIZE(grh_table),
 			&header->grh, buf + len);
 		len += IB_GRH_BYTES;
 	}

 	ib_pack(bth_table, ARRAY_SIZE(bth_table),
 		&header->bth, buf + len);
 	len += IB_BTH_BYTES;

 	ib_pack(deth_table, ARRAY_SIZE(deth_table),
 		&header->deth, buf + len);
 	len += IB_DETH_BYTES;

 	if (header->immediate_present) {
 		memcpy(buf + len, &header->immediate_data, sizeof header->immediate_data);
 		len += sizeof header->immediate_data;
 	}

 	return len;
 }
 EXPORT_SYMBOL(ib_ud_header_pack);

 /**
  * ib_ud_header_unpack - Unpack UD header struct from wire format
  * @header:UD header struct
  * @buf:Buffer to pack into
  *
  * ib_ud_header_pack() unpacks the UD header structure @header from wire
  * format in the buffer @buf.
  */
 int ib_ud_header_unpack(void                *buf,
 			struct ib_ud_header *header)
 {
 	ib_unpack(lrh_table, ARRAY_SIZE(lrh_table),
 		  buf, &header->lrh);
 	buf += IB_LRH_BYTES;

 	if (header->lrh.link_version != 0) {
 		printk(KERN_WARNING "Invalid LRH.link_version %d\n",
 		       header->lrh.link_version);
 		return -EINVAL;
 	}

 	switch (header->lrh.link_next_header) {
 	case IB_LNH_IBA_LOCAL:
 		header->grh_present = 0;
 		break;

 	case IB_LNH_IBA_GLOBAL:
 		header->grh_present = 1;
 		ib_unpack(grh_table, ARRAY_SIZE(grh_table),
 			  buf, &header->grh);
 		buf += IB_GRH_BYTES;

 		if (header->grh.ip_version != 6) {
 			printk(KERN_WARNING "Invalid GRH.ip_version %d\n",
 			       header->grh.ip_version);
 			return -EINVAL;
 		}
 		if (header->grh.next_header != 0x1b) {
 			printk(KERN_WARNING "Invalid GRH.next_header 0x%02x\n",
 			       header->grh.next_header);
 			return -EINVAL;
 		}
 		break;

 	default:
 		printk(KERN_WARNING "Invalid LRH.link_next_header %d\n",
 		       header->lrh.link_next_header);
 		return -EINVAL;
 	}

 	ib_unpack(bth_table, ARRAY_SIZE(bth_table),
 		  buf, &header->bth);
 	buf += IB_BTH_BYTES;

 	switch (header->bth.opcode) {
 	case IB_OPCODE_UD_SEND_ONLY:
 		header->immediate_present = 0;
 		break;
 	case IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE:
 		header->immediate_present = 1;
 		break;
 	default:
 		printk(KERN_WARNING "Invalid BTH.opcode 0x%02x\n",
 		       header->bth.opcode);
 		return -EINVAL;
 	}

 	if (header->bth.transport_header_version != 0) {
 		printk(KERN_WARNING "Invalid BTH.transport_header_version %d\n",
 		       header->bth.transport_header_version);
 		return -EINVAL;
 	}

 	ib_unpack(deth_table, ARRAY_SIZE(deth_table),
 		  buf, &header->deth);
 	buf += IB_DETH_BYTES;

 	if (header->immediate_present)
 		memcpy(&header->immediate_data, buf, sizeof header->immediate_data);

 	return 0;
 }
 EXPORT_SYMBOL(ib_ud_header_unpack);
	/*
	* Copyright (c) 2004 Topspin Corporation. All rights reserved.
	* Copyright (c) 2005 Sun Microsystems, Inc. All rights reserved.
	*
	* This software is available to you under a choice of one of two
	* licenses. You may choose to be licensed under the terms of the GNU
	* General Public License (GPL) Version 2, available from the file
	* COPYING in the main directory of this source tree, or the
	* OpenIB.org BSD license below:
	*
	* Redistribution and use in source and binary forms, with or
	* without modification, are permitted provided that the following
	* conditions are met:
	*
	* - Redistributions of source code must retain the above
	* copyright notice, this list of conditions and the following
	* disclaimer.
	*
	* - Redistributions in binary form must reproduce the above
	* copyright notice, this list of conditions and the following
	* disclaimer in the documentation and/or other materials
	* provided with the distribution.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	* SOFTWARE.
	*
	* $Id: ud_header.c 1349 2004-12-16 21:09:43Z roland $
	*/

	#include <linux/errno.h>
	#include <linux/string.h>

	#include <rdma/ib_pack.h>

	#define STRUCT_FIELD(header, field) \
	.struct_offset_bytes = offsetof(struct ib_unpacked_ ## header, field), \
	.struct_size_bytes = sizeof ((struct ib_unpacked_ ## header *) 0)->field, \
	.field_name = #header ":" #field

	static const struct ib_field lrh_table[] = {
	{ STRUCT_FIELD(lrh, virtual_lane),
	.offset_words = 0,
	.offset_bits = 0,
	.size_bits = 4 },
	{ STRUCT_FIELD(lrh, link_version),
	.offset_words = 0,
	.offset_bits = 4,
	.size_bits = 4 },
	{ STRUCT_FIELD(lrh, service_level),
	.offset_words = 0,
	.offset_bits = 8,
	.size_bits = 4 },
	{ RESERVED,
	.offset_words = 0,
	.offset_bits = 12,
	.size_bits = 2 },
	{ STRUCT_FIELD(lrh, link_next_header),
	.offset_words = 0,
	.offset_bits = 14,
	.size_bits = 2 },
	{ STRUCT_FIELD(lrh, destination_lid),
	.offset_words = 0,
	.offset_bits = 16,
	.size_bits = 16 },
	{ RESERVED,
	.offset_words = 1,
	.offset_bits = 0,
	.size_bits = 5 },
	{ STRUCT_FIELD(lrh, packet_length),
	.offset_words = 1,
	.offset_bits = 5,
	.size_bits = 11 },
	{ STRUCT_FIELD(lrh, source_lid),
	.offset_words = 1,
	.offset_bits = 16,
	.size_bits = 16 }
	};

	static const struct ib_field grh_table[] = {
	{ STRUCT_FIELD(grh, ip_version),
	.offset_words = 0,
	.offset_bits = 0,
	.size_bits = 4 },
	{ STRUCT_FIELD(grh, traffic_class),
	.offset_words = 0,
	.offset_bits = 4,
	.size_bits = 8 },
	{ STRUCT_FIELD(grh, flow_label),
	.offset_words = 0,
	.offset_bits = 12,
	.size_bits = 20 },
	{ STRUCT_FIELD(grh, payload_length),
	.offset_words = 1,
	.offset_bits = 0,
	.size_bits = 16 },
	{ STRUCT_FIELD(grh, next_header),
	.offset_words = 1,
	.offset_bits = 16,
	.size_bits = 8 },
	{ STRUCT_FIELD(grh, hop_limit),
	.offset_words = 1,
	.offset_bits = 24,
	.size_bits = 8 },
	{ STRUCT_FIELD(grh, source_gid),
	.offset_words = 2,
	.offset_bits = 0,
	.size_bits = 128 },
	{ STRUCT_FIELD(grh, destination_gid),
	.offset_words = 6,
	.offset_bits = 0,
	.size_bits = 128 }
	};

	static const struct ib_field bth_table[] = {
	{ STRUCT_FIELD(bth, opcode),
	.offset_words = 0,
	.offset_bits = 0,
	.size_bits = 8 },
	{ STRUCT_FIELD(bth, solicited_event),
	.offset_words = 0,
	.offset_bits = 8,
	.size_bits = 1 },
	{ STRUCT_FIELD(bth, mig_req),
	.offset_words = 0,
	.offset_bits = 9,
	.size_bits = 1 },
	{ STRUCT_FIELD(bth, pad_count),
	.offset_words = 0,
	.offset_bits = 10,
	.size_bits = 2 },
	{ STRUCT_FIELD(bth, transport_header_version),
	.offset_words = 0,
	.offset_bits = 12,
	.size_bits = 4 },
	{ STRUCT_FIELD(bth, pkey),
	.offset_words = 0,
	.offset_bits = 16,
	.size_bits = 16 },
	{ RESERVED,
	.offset_words = 1,
	.offset_bits = 0,
	.size_bits = 8 },
	{ STRUCT_FIELD(bth, destination_qpn),
	.offset_words = 1,
	.offset_bits = 8,
	.size_bits = 24 },
	{ STRUCT_FIELD(bth, ack_req),
	.offset_words = 2,
	.offset_bits = 0,
	.size_bits = 1 },
	{ RESERVED,
	.offset_words = 2,
	.offset_bits = 1,
	.size_bits = 7 },
	{ STRUCT_FIELD(bth, psn),
	.offset_words = 2,
	.offset_bits = 8,
	.size_bits = 24 }
	};

	static const struct ib_field deth_table[] = {
	{ STRUCT_FIELD(deth, qkey),
	.offset_words = 0,
	.offset_bits = 0,
	.size_bits = 32 },
	{ RESERVED,
	.offset_words = 1,
	.offset_bits = 0,
	.size_bits = 8 },
	{ STRUCT_FIELD(deth, source_qpn),
	.offset_words = 1,
	.offset_bits = 8,
	.size_bits = 24 }
	};

	/**
	* ib_ud_header_init - Initialize UD header structure
	* @payload_bytes:Length of packet payload
	* @grh_present:GRH flag (if non-zero, GRH will be included)
	* @header:Structure to initialize
	*
	* ib_ud_header_init() initializes the lrh.link_version, lrh.link_next_header,
	* lrh.packet_length, grh.ip_version, grh.payload_length,
	* grh.next_header, bth.opcode, bth.pad_count and
	* bth.transport_header_version fields of a &struct ib_ud_header given
	* the payload length and whether a GRH will be included.
	*/
	void ib_ud_header_init(int payload_bytes,
	int grh_present,
	struct ib_ud_header *header)
	{
	int header_len;
	u16 packet_length;

	memset(header, 0, sizeof *header);

	header_len =
	IB_LRH_BYTES +
	IB_BTH_BYTES +
	IB_DETH_BYTES;
	if (grh_present) {
	header_len += IB_GRH_BYTES;
	}

	header->lrh.link_version = 0;
	header->lrh.link_next_header =
	grh_present ? IB_LNH_IBA_GLOBAL : IB_LNH_IBA_LOCAL;
	packet_length = (IB_LRH_BYTES +
	IB_BTH_BYTES +
	IB_DETH_BYTES +
	payload_bytes +
	4 + /* ICRC */
	3) / 4; /* round up */

	header->grh_present = grh_present;
	if (grh_present) {
	packet_length += IB_GRH_BYTES / 4;
	header->grh.ip_version = 6;
	header->grh.payload_length =
	cpu_to_be16((IB_BTH_BYTES +
	IB_DETH_BYTES +
	payload_bytes +
	4 + /* ICRC */
	3) & ~3); /* round up */
	header->grh.next_header = 0x1b;
	}

	header->lrh.packet_length = cpu_to_be16(packet_length);

	if (header->immediate_present)
	header->bth.opcode = IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE;
	else
	header->bth.opcode = IB_OPCODE_UD_SEND_ONLY;
	header->bth.pad_count = (4 - payload_bytes) & 3;
	header->bth.transport_header_version = 0;
	}
	EXPORT_SYMBOL(ib_ud_header_init);

	/**
	* ib_ud_header_pack - Pack UD header struct into wire format
	* @header:UD header struct
	* @buf:Buffer to pack into
	*
	* ib_ud_header_pack() packs the UD header structure @header into wire
	* format in the buffer @buf.
	*/
	int ib_ud_header_pack(struct ib_ud_header *header,
	void *buf)
	{
	int len = 0;

	ib_pack(lrh_table, ARRAY_SIZE(lrh_table),
	&header->lrh, buf);
	len += IB_LRH_BYTES;

	if (header->grh_present) {
	ib_pack(grh_table, ARRAY_SIZE(grh_table),
	&header->grh, buf + len);
	len += IB_GRH_BYTES;
	}

	ib_pack(bth_table, ARRAY_SIZE(bth_table),
	&header->bth, buf + len);
	len += IB_BTH_BYTES;

	ib_pack(deth_table, ARRAY_SIZE(deth_table),
	&header->deth, buf + len);
	len += IB_DETH_BYTES;

	if (header->immediate_present) {
	memcpy(buf + len, &header->immediate_data, sizeof header->immediate_data);
	len += sizeof header->immediate_data;
	}

	return len;
	}
	EXPORT_SYMBOL(ib_ud_header_pack);

	/**
	* ib_ud_header_unpack - Unpack UD header struct from wire format
	* @header:UD header struct
	* @buf:Buffer to pack into
	*
	* ib_ud_header_pack() unpacks the UD header structure @header from wire
	* format in the buffer @buf.
	*/
	int ib_ud_header_unpack(void *buf,
	struct ib_ud_header *header)
	{
	ib_unpack(lrh_table, ARRAY_SIZE(lrh_table),
	buf, &header->lrh);
	buf += IB_LRH_BYTES;

	if (header->lrh.link_version != 0) {
	printk(KERN_WARNING "Invalid LRH.link_version %d\n",
	header->lrh.link_version);
	return -EINVAL;
	}

	switch (header->lrh.link_next_header) {
	case IB_LNH_IBA_LOCAL:
	header->grh_present = 0;
	break;

	case IB_LNH_IBA_GLOBAL:
	header->grh_present = 1;
	ib_unpack(grh_table, ARRAY_SIZE(grh_table),
	buf, &header->grh);
	buf += IB_GRH_BYTES;

	if (header->grh.ip_version != 6) {
	printk(KERN_WARNING "Invalid GRH.ip_version %d\n",
	header->grh.ip_version);
	return -EINVAL;
	}
	if (header->grh.next_header != 0x1b) {
	printk(KERN_WARNING "Invalid GRH.next_header 0x%02x\n",
	header->grh.next_header);
	return -EINVAL;
	}
	break;

	default:
	printk(KERN_WARNING "Invalid LRH.link_next_header %d\n",
	header->lrh.link_next_header);
	return -EINVAL;
	}

	ib_unpack(bth_table, ARRAY_SIZE(bth_table),
	buf, &header->bth);
	buf += IB_BTH_BYTES;

	switch (header->bth.opcode) {
	case IB_OPCODE_UD_SEND_ONLY:
	header->immediate_present = 0;
	break;
	case IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE:
	header->immediate_present = 1;
	break;
	default:
	printk(KERN_WARNING "Invalid BTH.opcode 0x%02x\n",
	header->bth.opcode);
	return -EINVAL;
	}

	if (header->bth.transport_header_version != 0) {
	printk(KERN_WARNING "Invalid BTH.transport_header_version %d\n",
	header->bth.transport_header_version);
	return -EINVAL;
	}

	ib_unpack(deth_table, ARRAY_SIZE(deth_table),
	buf, &header->deth);
	buf += IB_DETH_BYTES;

	if (header->immediate_present)
	memcpy(&header->immediate_data, buf, sizeof header->immediate_data);

	return 0;
	}
	EXPORT_SYMBOL(ib_ud_header_unpack);