gpxe/src/net/infiniband/ib_srp.c - platform/external/syslinux - Git at Google

 /*
  * Copyright (C) 2009 Fen Systems Ltd <mbrown@fensystems.co.uk>.
  * All rights reserved.
  *
  * 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.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
  * COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
  * OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 FILE_LICENCE ( BSD2 );

 #include <stdlib.h>
 #include <errno.h>
 #include <gpxe/srp.h>
 #include <gpxe/infiniband.h>
 #include <gpxe/ib_cmrc.h>
 #include <gpxe/ib_srp.h>

 /**
  * @file
  *
  * SCSI RDMA Protocol over Infiniband
  *
  */

 /* Disambiguate the various possible EINVALs */
 #define EINVAL_BYTE_STRING_LEN ( EINVAL | EUNIQ_01 )
 #define EINVAL_BYTE_STRING ( EINVAL | EUNIQ_02 )
 #define EINVAL_INTEGER ( EINVAL | EUNIQ_03 )
 #define EINVAL_RP_TOO_SHORT ( EINVAL | EUNIQ_04 )

 /** IB SRP parse flags */
 enum ib_srp_parse_flags {
 	IB_SRP_PARSE_REQUIRED = 0x0000,
 	IB_SRP_PARSE_OPTIONAL = 0x8000,
 	IB_SRP_PARSE_FLAG_MASK = 0xf000,
 };

 /** IB SRP root path parameters */
 struct ib_srp_root_path {
 	/** SCSI LUN */
 	struct scsi_lun *lun;
 	/** SRP port IDs */
 	struct srp_port_ids *port_ids;
 	/** IB SRP parameters */
 	struct ib_srp_parameters *ib;
 };

 /**
  * Parse IB SRP root path byte-string value
  *
  * @v rp_comp		Root path component string
  * @v default_value	Default value to use if component string is empty
  * @ret value		Value
  */
 static int ib_srp_parse_byte_string ( const char *rp_comp, uint8_t *bytes,
 				      unsigned int size_flags ) {
 	size_t size = ( size_flags & ~IB_SRP_PARSE_FLAG_MASK );
 	size_t rp_comp_len = strlen ( rp_comp );
 	char buf[3];
 	char *buf_end;

 	/* Allow optional components to be empty */
 	if ( ( rp_comp_len == 0 ) &&
 	     ( size_flags & IB_SRP_PARSE_OPTIONAL ) )
 		return 0;

 	/* Check string length */
 	if ( rp_comp_len != ( 2 * size ) )
 		return -EINVAL_BYTE_STRING_LEN;

 	/* Parse byte string */
 	for ( ; size ; size--, rp_comp += 2, bytes++ ) {
 		memcpy ( buf, rp_comp, 2 );
 		buf[2] = '\0';
 		*bytes = strtoul ( buf, &buf_end, 16 );
 		if ( buf_end != &buf[2] )
 			return -EINVAL_BYTE_STRING;
 	}
 	return 0;
 }

 /**
  * Parse IB SRP root path integer value
  *
  * @v rp_comp		Root path component string
  * @v default_value	Default value to use if component string is empty
  * @ret value		Value
  */
 static int ib_srp_parse_integer ( const char *rp_comp, int default_value ) {
 	int value;
 	char *end;

 	value = strtoul ( rp_comp, &end, 16 );
 	if ( *end )
 		return -EINVAL_INTEGER;

 	if ( end == rp_comp )
 		return default_value;

 	return value;
 }

 /**
  * Parse IB SRP root path literal component
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_literal ( const char *rp_comp __unused,
 				  struct ib_srp_root_path *rp __unused ) {
 	/* Ignore */
 	return 0;
 }

 /**
  * Parse IB SRP root path source GID
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_sgid ( const char *rp_comp,
 			       struct ib_srp_root_path *rp ) {
 	struct ib_device *ibdev;

 	/* Default to the GID of the last opened Infiniband device */
 	if ( ( ibdev = last_opened_ibdev() ) != NULL )
 		memcpy ( &rp->ib->sgid, &ibdev->gid, sizeof ( rp->ib->sgid ) );

 	return ib_srp_parse_byte_string ( rp_comp, rp->ib->sgid.u.bytes,
 					  ( sizeof ( rp->ib->sgid ) |
 					    IB_SRP_PARSE_OPTIONAL ) );
 }

 /**
  * Parse IB SRP root path initiator identifier extension
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_initiator_id_ext ( const char *rp_comp,
 					   struct ib_srp_root_path *rp ) {
 	struct ib_srp_initiator_port_id *port_id =
 		ib_srp_initiator_port_id ( rp->port_ids );

 	return ib_srp_parse_byte_string ( rp_comp, port_id->id_ext.u.bytes,
 					  ( sizeof ( port_id->id_ext ) |
 					    IB_SRP_PARSE_OPTIONAL ) );
 }

 /**
  * Parse IB SRP root path initiator HCA GUID
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_initiator_hca_guid ( const char *rp_comp,
 					     struct ib_srp_root_path *rp ) {
 	struct ib_srp_initiator_port_id *port_id =
 		ib_srp_initiator_port_id ( rp->port_ids );

 	/* Default to the GUID portion of the source GID */
 	memcpy ( &port_id->hca_guid, &rp->ib->sgid.u.half[1],
 		 sizeof ( port_id->hca_guid ) );

 	return ib_srp_parse_byte_string ( rp_comp, port_id->hca_guid.u.bytes,
 					  ( sizeof ( port_id->hca_guid ) |
 					    IB_SRP_PARSE_OPTIONAL ) );
 }

 /**
  * Parse IB SRP root path destination GID
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_dgid ( const char *rp_comp,
 			       struct ib_srp_root_path *rp ) {
 	return ib_srp_parse_byte_string ( rp_comp, rp->ib->dgid.u.bytes,
 					  ( sizeof ( rp->ib->dgid ) |
 					    IB_SRP_PARSE_REQUIRED ) );
 }

 /**
  * Parse IB SRP root path partition key
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_pkey ( const char *rp_comp,
 			       struct ib_srp_root_path *rp ) {
 	int pkey;

 	if ( ( pkey = ib_srp_parse_integer ( rp_comp, IB_PKEY_DEFAULT ) ) < 0 )
 		return pkey;
 	rp->ib->pkey = pkey;
 	return 0;
 }

 /**
  * Parse IB SRP root path service ID
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_service_id ( const char *rp_comp,
 				     struct ib_srp_root_path *rp ) {
 	return ib_srp_parse_byte_string ( rp_comp, rp->ib->service_id.u.bytes,
 					  ( sizeof ( rp->ib->service_id ) |
 					    IB_SRP_PARSE_REQUIRED ) );
 }

 /**
  * Parse IB SRP root path LUN
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_lun ( const char *rp_comp,
 			      struct ib_srp_root_path *rp ) {
 	return scsi_parse_lun ( rp_comp, rp->lun );
 }

 /**
  * Parse IB SRP root path target identifier extension
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_target_id_ext ( const char *rp_comp,
 					struct ib_srp_root_path *rp ) {
 	struct ib_srp_target_port_id *port_id =
 		ib_srp_target_port_id ( rp->port_ids );

 	return ib_srp_parse_byte_string ( rp_comp, port_id->id_ext.u.bytes,
 					  ( sizeof ( port_id->id_ext ) |
 					    IB_SRP_PARSE_REQUIRED ) );
 }

 /**
  * Parse IB SRP root path target I/O controller GUID
  *
  * @v rp_comp		Root path component string
  * @v rp		IB SRP root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_target_ioc_guid ( const char *rp_comp,
 					  struct ib_srp_root_path *rp ) {
 	struct ib_srp_target_port_id *port_id =
 		ib_srp_target_port_id ( rp->port_ids );

 	return ib_srp_parse_byte_string ( rp_comp, port_id->ioc_guid.u.bytes,
 					  ( sizeof ( port_id->ioc_guid ) |
 					    IB_SRP_PARSE_REQUIRED ) );
 }

 /** IB SRP root path component parser */
 struct ib_srp_root_path_parser {
 	/**
 	 * Parse IB SRP root path component
 	 *
 	 * @v rp_comp		Root path component string
 	 * @v rp		IB SRP root path
 	 * @ret rc		Return status code
 	 */
 	int ( * parse ) ( const char *rp_comp, struct ib_srp_root_path *rp );
 };

 /** IB SRP root path components */
 static struct ib_srp_root_path_parser ib_srp_rp_parser[] = {
 	{ ib_srp_parse_literal },
 	{ ib_srp_parse_sgid },
 	{ ib_srp_parse_initiator_id_ext },
 	{ ib_srp_parse_initiator_hca_guid },
 	{ ib_srp_parse_dgid },
 	{ ib_srp_parse_pkey },
 	{ ib_srp_parse_service_id },
 	{ ib_srp_parse_lun },
 	{ ib_srp_parse_target_id_ext },
 	{ ib_srp_parse_target_ioc_guid },
 };

 /** Number of IB SRP root path components */
 #define IB_SRP_NUM_RP_COMPONENTS \
 	( sizeof ( ib_srp_rp_parser ) / sizeof ( ib_srp_rp_parser[0] ) )

 /**
  * Parse IB SRP root path
  *
  * @v srp		SRP device
  * @v rp_string		Root path
  * @ret rc		Return status code
  */
 static int ib_srp_parse_root_path ( struct srp_device *srp,
 				    const char *rp_string ) {
 	struct ib_srp_parameters *ib_params = ib_srp_params ( srp );
 	struct ib_srp_root_path rp = {
 		.lun = &srp->lun,
 		.port_ids = &srp->port_ids,
 		.ib = ib_params,
 	};
 	char rp_string_copy[ strlen ( rp_string ) + 1 ];
 	char *rp_comp[IB_SRP_NUM_RP_COMPONENTS];
 	char *rp_string_tmp = rp_string_copy;
 	unsigned int i = 0;
 	int rc;

 	/* Split root path into component parts */
 	strcpy ( rp_string_copy, rp_string );
 	while ( 1 ) {
 		rp_comp[i++] = rp_string_tmp;
 		if ( i == IB_SRP_NUM_RP_COMPONENTS )
 			break;
 		for ( ; *rp_string_tmp != ':' ; rp_string_tmp++ ) {
 			if ( ! *rp_string_tmp ) {
 				DBGC ( srp, "SRP %p root path \"%s\" too "
 				       "short\n", srp, rp_string );
 				return -EINVAL_RP_TOO_SHORT;
 			}
 		}
 		*(rp_string_tmp++) = '\0';
 	}

 	/* Parse root path components */
 	for ( i = 0 ; i < IB_SRP_NUM_RP_COMPONENTS ; i++ ) {
 		if ( ( rc = ib_srp_rp_parser[i].parse ( rp_comp[i],
 							&rp ) ) != 0 ) {
 			DBGC ( srp, "SRP %p could not parse \"%s\" in root "
 			       "path \"%s\": %s\n", srp, rp_comp[i],
 			       rp_string, strerror ( rc ) );
 			return rc;
 		}
 	}

 	return 0;
 }

 /**
  * Connect IB SRP session
  *
  * @v srp		SRP device
  * @ret rc		Return status code
  */
 static int ib_srp_connect ( struct srp_device *srp ) {
 	struct ib_srp_parameters *ib_params = ib_srp_params ( srp );
 	struct ib_device *ibdev;
 	int rc;

 	/* Identify Infiniband device */
 	ibdev = find_ibdev ( &ib_params->sgid );
 	if ( ! ibdev ) {
 		DBGC ( srp, "SRP %p could not identify Infiniband device\n",
 		       srp );
 		return -ENODEV;
 	}

 	/* Configure remaining SRP parameters */
 	srp->memory_handle = ibdev->rdma_key;

 	/* Open CMRC socket */
 	if ( ( rc = ib_cmrc_open ( &srp->socket, ibdev, &ib_params->dgid,
 				   &ib_params->service_id ) ) != 0 ) {
 		DBGC ( srp, "SRP %p could not open CMRC socket: %s\n",
 		       srp, strerror ( rc ) );
 		return rc;
 	}

 	return 0;
 }

 /** IB SRP transport type */
 struct srp_transport_type ib_srp_transport = {
 	.priv_len = sizeof ( struct ib_srp_parameters ),
 	.parse_root_path = ib_srp_parse_root_path,
 	.connect = ib_srp_connect,
 };
	/*
	* Copyright (C) 2009 Fen Systems Ltd <mbrown@fensystems.co.uk>.
	* All rights reserved.
	*
	* 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.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
	* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
	* COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
	* INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
	* (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
	* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
	* STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
	* OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	FILE_LICENCE ( BSD2 );

	#include <stdlib.h>
	#include <errno.h>
	#include <gpxe/srp.h>
	#include <gpxe/infiniband.h>
	#include <gpxe/ib_cmrc.h>
	#include <gpxe/ib_srp.h>

	/**
	* @file
	*
	* SCSI RDMA Protocol over Infiniband
	*
	*/

	/* Disambiguate the various possible EINVALs */
	#define EINVAL_BYTE_STRING_LEN ( EINVAL \| EUNIQ_01 )
	#define EINVAL_BYTE_STRING ( EINVAL \| EUNIQ_02 )
	#define EINVAL_INTEGER ( EINVAL \| EUNIQ_03 )
	#define EINVAL_RP_TOO_SHORT ( EINVAL \| EUNIQ_04 )

	/** IB SRP parse flags */
	enum ib_srp_parse_flags {
	IB_SRP_PARSE_REQUIRED = 0x0000,
	IB_SRP_PARSE_OPTIONAL = 0x8000,
	IB_SRP_PARSE_FLAG_MASK = 0xf000,
	};

	/** IB SRP root path parameters */
	struct ib_srp_root_path {
	/** SCSI LUN */
	struct scsi_lun *lun;
	/** SRP port IDs */
	struct srp_port_ids *port_ids;
	/** IB SRP parameters */
	struct ib_srp_parameters *ib;
	};

	/**
	* Parse IB SRP root path byte-string value
	*
	* @v rp_comp Root path component string
	* @v default_value Default value to use if component string is empty
	* @ret value Value
	*/
	static int ib_srp_parse_byte_string ( const char rp_comp, uint8_t bytes,
	unsigned int size_flags ) {
	size_t size = ( size_flags & ~IB_SRP_PARSE_FLAG_MASK );
	size_t rp_comp_len = strlen ( rp_comp );
	char buf[3];
	char *buf_end;

	/* Allow optional components to be empty */
	if ( ( rp_comp_len == 0 ) &&
	( size_flags & IB_SRP_PARSE_OPTIONAL ) )
	return 0;

	/* Check string length */
	if ( rp_comp_len != ( 2 * size ) )
	return -EINVAL_BYTE_STRING_LEN;

	/* Parse byte string */
	for ( ; size ; size--, rp_comp += 2, bytes++ ) {
	memcpy ( buf, rp_comp, 2 );
	buf[2] = '\0';
	*bytes = strtoul ( buf, &buf_end, 16 );
	if ( buf_end != &buf[2] )
	return -EINVAL_BYTE_STRING;
	}
	return 0;
	}

	/**
	* Parse IB SRP root path integer value
	*
	* @v rp_comp Root path component string
	* @v default_value Default value to use if component string is empty
	* @ret value Value
	*/
	static int ib_srp_parse_integer ( const char *rp_comp, int default_value ) {
	int value;
	char *end;

	value = strtoul ( rp_comp, &end, 16 );
	if ( *end )
	return -EINVAL_INTEGER;

	if ( end == rp_comp )
	return default_value;

	return value;
	}

	/**
	* Parse IB SRP root path literal component
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_literal ( const char *rp_comp __unused,
	struct ib_srp_root_path *rp __unused ) {
	/* Ignore */
	return 0;
	}

	/**
	* Parse IB SRP root path source GID
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_sgid ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	struct ib_device *ibdev;

	/* Default to the GID of the last opened Infiniband device */
	if ( ( ibdev = last_opened_ibdev() ) != NULL )
	memcpy ( &rp->ib->sgid, &ibdev->gid, sizeof ( rp->ib->sgid ) );

	return ib_srp_parse_byte_string ( rp_comp, rp->ib->sgid.u.bytes,
	( sizeof ( rp->ib->sgid ) \|
	IB_SRP_PARSE_OPTIONAL ) );
	}

	/**
	* Parse IB SRP root path initiator identifier extension
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_initiator_id_ext ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	struct ib_srp_initiator_port_id *port_id =
	ib_srp_initiator_port_id ( rp->port_ids );

	return ib_srp_parse_byte_string ( rp_comp, port_id->id_ext.u.bytes,
	( sizeof ( port_id->id_ext ) \|
	IB_SRP_PARSE_OPTIONAL ) );
	}

	/**
	* Parse IB SRP root path initiator HCA GUID
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_initiator_hca_guid ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	struct ib_srp_initiator_port_id *port_id =
	ib_srp_initiator_port_id ( rp->port_ids );

	/* Default to the GUID portion of the source GID */
	memcpy ( &port_id->hca_guid, &rp->ib->sgid.u.half[1],
	sizeof ( port_id->hca_guid ) );

	return ib_srp_parse_byte_string ( rp_comp, port_id->hca_guid.u.bytes,
	( sizeof ( port_id->hca_guid ) \|
	IB_SRP_PARSE_OPTIONAL ) );
	}

	/**
	* Parse IB SRP root path destination GID
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_dgid ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	return ib_srp_parse_byte_string ( rp_comp, rp->ib->dgid.u.bytes,
	( sizeof ( rp->ib->dgid ) \|
	IB_SRP_PARSE_REQUIRED ) );
	}

	/**
	* Parse IB SRP root path partition key
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_pkey ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	int pkey;

	if ( ( pkey = ib_srp_parse_integer ( rp_comp, IB_PKEY_DEFAULT ) ) < 0 )
	return pkey;
	rp->ib->pkey = pkey;
	return 0;
	}

	/**
	* Parse IB SRP root path service ID
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_service_id ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	return ib_srp_parse_byte_string ( rp_comp, rp->ib->service_id.u.bytes,
	( sizeof ( rp->ib->service_id ) \|
	IB_SRP_PARSE_REQUIRED ) );
	}

	/**
	* Parse IB SRP root path LUN
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_lun ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	return scsi_parse_lun ( rp_comp, rp->lun );
	}

	/**
	* Parse IB SRP root path target identifier extension
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_target_id_ext ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	struct ib_srp_target_port_id *port_id =
	ib_srp_target_port_id ( rp->port_ids );

	return ib_srp_parse_byte_string ( rp_comp, port_id->id_ext.u.bytes,
	( sizeof ( port_id->id_ext ) \|
	IB_SRP_PARSE_REQUIRED ) );
	}

	/**
	* Parse IB SRP root path target I/O controller GUID
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_target_ioc_guid ( const char *rp_comp,
	struct ib_srp_root_path *rp ) {
	struct ib_srp_target_port_id *port_id =
	ib_srp_target_port_id ( rp->port_ids );

	return ib_srp_parse_byte_string ( rp_comp, port_id->ioc_guid.u.bytes,
	( sizeof ( port_id->ioc_guid ) \|
	IB_SRP_PARSE_REQUIRED ) );
	}

	/** IB SRP root path component parser */
	struct ib_srp_root_path_parser {
	/**
	* Parse IB SRP root path component
	*
	* @v rp_comp Root path component string
	* @v rp IB SRP root path
	* @ret rc Return status code
	*/
	int ( * parse ) ( const char rp_comp, struct ib_srp_root_path rp );
	};

	/** IB SRP root path components */
	static struct ib_srp_root_path_parser ib_srp_rp_parser[] = {
	{ ib_srp_parse_literal },
	{ ib_srp_parse_sgid },
	{ ib_srp_parse_initiator_id_ext },
	{ ib_srp_parse_initiator_hca_guid },
	{ ib_srp_parse_dgid },
	{ ib_srp_parse_pkey },
	{ ib_srp_parse_service_id },
	{ ib_srp_parse_lun },
	{ ib_srp_parse_target_id_ext },
	{ ib_srp_parse_target_ioc_guid },
	};

	/** Number of IB SRP root path components */
	#define IB_SRP_NUM_RP_COMPONENTS \
	( sizeof ( ib_srp_rp_parser ) / sizeof ( ib_srp_rp_parser[0] ) )

	/**
	* Parse IB SRP root path
	*
	* @v srp SRP device
	* @v rp_string Root path
	* @ret rc Return status code
	*/
	static int ib_srp_parse_root_path ( struct srp_device *srp,
	const char *rp_string ) {
	struct ib_srp_parameters *ib_params = ib_srp_params ( srp );
	struct ib_srp_root_path rp = {
	.lun = &srp->lun,
	.port_ids = &srp->port_ids,
	.ib = ib_params,
	};
	char rp_string_copy[ strlen ( rp_string ) + 1 ];
	char *rp_comp[IB_SRP_NUM_RP_COMPONENTS];
	char *rp_string_tmp = rp_string_copy;
	unsigned int i = 0;
	int rc;

	/* Split root path into component parts */
	strcpy ( rp_string_copy, rp_string );
	while ( 1 ) {
	rp_comp[i++] = rp_string_tmp;
	if ( i == IB_SRP_NUM_RP_COMPONENTS )
	break;
	for ( ; *rp_string_tmp != ':' ; rp_string_tmp++ ) {
	if ( ! *rp_string_tmp ) {
	DBGC ( srp, "SRP %p root path \"%s\" too "
	"short\n", srp, rp_string );
	return -EINVAL_RP_TOO_SHORT;
	}
	}
	*(rp_string_tmp++) = '\0';
	}

	/* Parse root path components */
	for ( i = 0 ; i < IB_SRP_NUM_RP_COMPONENTS ; i++ ) {
	if ( ( rc = ib_srp_rp_parser[i].parse ( rp_comp[i],
	&rp ) ) != 0 ) {
	DBGC ( srp, "SRP %p could not parse \"%s\" in root "
	"path \"%s\": %s\n", srp, rp_comp[i],
	rp_string, strerror ( rc ) );
	return rc;
	}
	}

	return 0;
	}

	/**
	* Connect IB SRP session
	*
	* @v srp SRP device
	* @ret rc Return status code
	*/
	static int ib_srp_connect ( struct srp_device *srp ) {
	struct ib_srp_parameters *ib_params = ib_srp_params ( srp );
	struct ib_device *ibdev;
	int rc;

	/* Identify Infiniband device */
	ibdev = find_ibdev ( &ib_params->sgid );
	if ( ! ibdev ) {
	DBGC ( srp, "SRP %p could not identify Infiniband device\n",
	srp );
	return -ENODEV;
	}

	/* Configure remaining SRP parameters */
	srp->memory_handle = ibdev->rdma_key;

	/* Open CMRC socket */
	if ( ( rc = ib_cmrc_open ( &srp->socket, ibdev, &ib_params->dgid,
	&ib_params->service_id ) ) != 0 ) {
	DBGC ( srp, "SRP %p could not open CMRC socket: %s\n",
	srp, strerror ( rc ) );
	return rc;
	}

	return 0;
	}

	/** IB SRP transport type */
	struct srp_transport_type ib_srp_transport = {
	.priv_len = sizeof ( struct ib_srp_parameters ),
	.parse_root_path = ib_srp_parse_root_path,
	.connect = ib_srp_connect,
	};