IB: Add SCSI RDMA Protocol (SRP) initiator

Add an InfiniBand SCSI RDMA Protocol (SRP) initiator.  This driver is
used to talk talk to InfiniBand SRP targets (storage devices).

Signed-off-by: Roland Dreier <rolandd@cisco.com>

drivers/infiniband/Kconfig

@@ -33,4 +33,6 @@ source "drivers/infiniband/hw/mthca/Kconfig"
 
 source "drivers/infiniband/ulp/ipoib/Kconfig"
 
+source "drivers/infiniband/ulp/srp/Kconfig"
+
 endmenu

drivers/infiniband/Makefile

 obj-$(CONFIG_INFINIBAND)		+= core/
 obj-$(CONFIG_INFINIBAND_MTHCA)		+= hw/mthca/
 obj-$(CONFIG_INFINIBAND_IPOIB)		+= ulp/ipoib/
+obj-$(CONFIG_INFINIBAND_SRP)		+= ulp/srp/

drivers/infiniband/ulp/srp/Kbuild

+obj-$(CONFIG_INFINIBAND_SRP)			+= ib_srp.o

drivers/infiniband/ulp/srp/Kconfig

+config INFINIBAND_SRP
+	tristate "InfiniBand SCSI RDMA Protocol"
+	depends on INFINIBAND && SCSI
+	---help---
+	  Support for the SCSI RDMA Protocol over InfiniBand.  This
+	  allows you to access storage devices that speak SRP over
+	  InfiniBand.
+
+	  The SRP protocol is defined by the INCITS T10 technical
+	  committee.  See <http://www.t10.org/>.
+

drivers/infiniband/ulp/srp/ib_srp.h

+/*
+ * Copyright (c) 2005 Cisco Systems.  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: ib_srp.h 3932 2005-11-01 17:19:29Z roland $
+ */
+
+#ifndef IB_SRP_H
+#define IB_SRP_H
+
+#include <linux/types.h>
+#include <linux/list.h>
+
+#include <asm/semaphore.h>
+
+#include <scsi/scsi_host.h>
+#include <scsi/scsi_cmnd.h>
+
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_sa.h>
+#include <rdma/ib_cm.h>
+
+enum {
+	SRP_PATH_REC_TIMEOUT_MS	= 1000,
+	SRP_ABORT_TIMEOUT_MS	= 5000,
+
+	SRP_PORT_REDIRECT	= 1,
+	SRP_DLID_REDIRECT	= 2,
+
+	SRP_MAX_IU_LEN		= 256,
+
+	SRP_RQ_SHIFT    	= 6,
+	SRP_RQ_SIZE		= 1 << SRP_RQ_SHIFT,
+	SRP_SQ_SIZE		= SRP_RQ_SIZE - 1,
+	SRP_CQ_SIZE		= SRP_SQ_SIZE + SRP_RQ_SIZE,
+
+	SRP_TAG_TSK_MGMT	= 1 << (SRP_RQ_SHIFT + 1)
+};
+
+#define SRP_OP_RECV		(1 << 31)
+#define SRP_MAX_INDIRECT	((SRP_MAX_IU_LEN -			\
+				  sizeof (struct srp_cmd) -		\
+				  sizeof (struct srp_indirect_buf)) / 16)
+
+enum srp_target_state {
+	SRP_TARGET_LIVE,
+	SRP_TARGET_CONNECTING,
+	SRP_TARGET_DEAD,
+	SRP_TARGET_REMOVED
+};
+
+struct srp_host {
+	u8			initiator_port_id[16];
+	struct ib_device       *dev;
+	u8                      port;
+	struct ib_pd	       *pd;
+	struct ib_mr	       *mr;
+	struct class_device	class_dev;
+	struct list_head	target_list;
+	struct semaphore        target_mutex;
+	struct completion	released;
+	struct list_head	list;
+};
+
+struct srp_request {
+	struct list_head	list;
+	struct scsi_cmnd       *scmnd;
+	struct srp_iu	       *cmd;
+	struct srp_iu	       *tsk_mgmt;
+	DECLARE_PCI_UNMAP_ADDR(direct_mapping)
+	struct completion	done;
+	short			next;
+	u8			cmd_done;
+	u8			tsk_status;
+};
+
+struct srp_target_port {
+	__be64			id_ext;
+	__be64			ioc_guid;
+	__be64			service_id;
+	struct srp_host	       *srp_host;
+	struct Scsi_Host       *scsi_host;
+	char			target_name[32];
+	unsigned int		scsi_id;
+
+	struct ib_sa_path_rec	path;
+	struct ib_sa_query     *path_query;
+	int			path_query_id;
+
+	struct ib_cm_id	       *cm_id;
+	struct ib_cq	       *cq;
+	struct ib_qp	       *qp;
+
+	int			max_ti_iu_len;
+	s32			req_lim;
+
+	unsigned		rx_head;
+	struct srp_iu	       *rx_ring[SRP_RQ_SIZE];
+
+	unsigned		tx_head;
+	unsigned		tx_tail;
+	struct srp_iu	       *tx_ring[SRP_SQ_SIZE + 1];
+
+	int			req_head;
+	struct list_head	req_queue;
+	struct srp_request	req_ring[SRP_SQ_SIZE];
+
+	struct work_struct	work;
+
+	struct list_head	list;
+	struct completion	done;
+	int			status;
+	enum srp_target_state	state;
+};
+
+struct srp_iu {
+	dma_addr_t		dma;
+	void		       *buf;
+	size_t			size;
+	enum dma_data_direction	direction;
+};
+
+#endif /* IB_SRP_H */

include/scsi/srp.h

+/*
+ * Copyright (c) 2005 Cisco Systems.  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.
+ *
+ * $Id$
+ */
+
+#ifndef SCSI_SRP_H
+#define SCSI_SRP_H
+
+/*
+ * Structures and constants for the SCSI RDMA Protocol (SRP) as
+ * defined by the INCITS T10 committee.  This file was written using
+ * draft Revision 16a of the SRP standard.
+ */
+
+#include <linux/types.h>
+
+enum {
+	SRP_LOGIN_REQ	= 0x00,
+	SRP_TSK_MGMT	= 0x01,
+	SRP_CMD		= 0x02,
+	SRP_I_LOGOUT	= 0x03,
+	SRP_LOGIN_RSP	= 0xc0,
+	SRP_RSP		= 0xc1,
+	SRP_LOGIN_REJ	= 0xc2,
+	SRP_T_LOGOUT	= 0x80,
+	SRP_CRED_REQ	= 0x81,
+	SRP_AER_REQ	= 0x82,
+	SRP_CRED_RSP	= 0x41,
+	SRP_AER_RSP	= 0x42
+};
+
+enum {
+	SRP_BUF_FORMAT_DIRECT	= 1 << 1,
+	SRP_BUF_FORMAT_INDIRECT	= 1 << 2
+};
+
+enum {
+	SRP_NO_DATA_DESC	= 0,
+	SRP_DATA_DESC_DIRECT	= 1,
+	SRP_DATA_DESC_INDIRECT	= 2
+};
+
+enum {
+	SRP_TSK_ABORT_TASK	= 0x01,
+	SRP_TSK_ABORT_TASK_SET	= 0x02,
+	SRP_TSK_CLEAR_TASK_SET	= 0x04,
+	SRP_TSK_LUN_RESET	= 0x08,
+	SRP_TSK_CLEAR_ACA	= 0x40
+};
+
+enum srp_login_rej_reason {
+	SRP_LOGIN_REJ_UNABLE_ESTABLISH_CHANNEL		= 0x00010000,
+	SRP_LOGIN_REJ_INSUFFICIENT_RESOURCES		= 0x00010001,
+	SRP_LOGIN_REJ_REQ_IT_IU_LENGTH_TOO_LARGE	= 0x00010002,
+	SRP_LOGIN_REJ_UNABLE_ASSOCIATE_CHANNEL		= 0x00010003,
+	SRP_LOGIN_REJ_UNSUPPORTED_DESCRIPTOR_FMT	= 0x00010004,
+	SRP_LOGIN_REJ_MULTI_CHANNEL_UNSUPPORTED		= 0x00010005,
+	SRP_LOGIN_REJ_CHANNEL_LIMIT_REACHED		= 0x00010006
+};
+
+struct srp_direct_buf {
+	__be64	va;
+	__be32	key;
+	__be32  len;
+};
+
+/*
+ * We need the packed attribute because the SRP spec puts the list of
+ * descriptors at an offset of 20, which is not aligned to the size
+ * of struct srp_direct_buf.
+ */
+struct srp_indirect_buf {
+	struct srp_direct_buf	table_desc;
+	__be32			len;
+	struct srp_direct_buf	desc_list[0] __attribute__((packed));
+};
+
+enum {
+	SRP_MULTICHAN_SINGLE = 0,
+	SRP_MULTICHAN_MULTI  = 1
+};
+
+struct srp_login_req {
+	u8	opcode;
+	u8	reserved1[7];
+	u64	tag;
+	__be32	req_it_iu_len;
+	u8	reserved2[4];
+	__be16	req_buf_fmt;
+	u8	req_flags;
+	u8	reserved3[5];
+	u8	initiator_port_id[16];
+	u8	target_port_id[16];
+};
+
+struct srp_login_rsp {
+	u8	opcode;
+	u8	reserved1[3];
+	__be32	req_lim_delta;
+	u64	tag;
+	__be32	max_it_iu_len;
+	__be32	max_ti_iu_len;
+	__be16	buf_fmt;
+	u8	rsp_flags;
+	u8	reserved2[25];
+};
+
+struct srp_login_rej {
+	u8	opcode;
+	u8	reserved1[3];
+	__be32	reason;
+	u64	tag;
+	u8	reserved2[8];
+	__be16	buf_fmt;
+	u8	reserved3[6];
+};
+
+struct srp_i_logout {
+	u8	opcode;
+	u8	reserved[7];
+	u64	tag;
+};
+
+struct srp_t_logout {
+	u8	opcode;
+	u8	sol_not;
+	u8	reserved[2];
+	__be32	reason;
+	u64	tag;
+};
+
+/*
+ * We need the packed attribute because the SRP spec only aligns the
+ * 8-byte LUN field to 4 bytes.
+ */
+struct srp_tsk_mgmt {
+	u8	opcode;
+	u8	sol_not;
+	u8	reserved1[6];
+	u64	tag;
+	u8	reserved2[4];
+	__be64	lun __attribute__((packed));
+	u8	reserved3[2];
+	u8	tsk_mgmt_func;
+	u8	reserved4;
+	u64	task_tag;
+	u8	reserved5[8];
+};
+
+/*
+ * We need the packed attribute because the SRP spec only aligns the
+ * 8-byte LUN field to 4 bytes.
+ */
+struct srp_cmd {
+	u8	opcode;
+	u8	sol_not;
+	u8	reserved1[3];
+	u8	buf_fmt;
+	u8	data_out_desc_cnt;
+	u8	data_in_desc_cnt;
+	u64	tag;
+	u8	reserved2[4];
+	__be64	lun __attribute__((packed));
+	u8	reserved3;
+	u8	task_attr;
+	u8	reserved4;
+	u8	add_cdb_len;
+	u8	cdb[16];
+	u8	add_data[0];
+};
+
+enum {
+	SRP_RSP_FLAG_RSPVALID = 1 << 0,
+	SRP_RSP_FLAG_SNSVALID = 1 << 1,
+	SRP_RSP_FLAG_DOOVER   = 1 << 2,
+	SRP_RSP_FLAG_DOUNDER  = 1 << 3,
+	SRP_RSP_FLAG_DIOVER   = 1 << 4,
+	SRP_RSP_FLAG_DIUNDER  = 1 << 5
+};
+
+struct srp_rsp {
+	u8	opcode;
+	u8	sol_not;
+	u8	reserved1[2];
+	__be32	req_lim_delta;
+	u64	tag;
+	u8	reserved2[2];
+	u8	flags;
+	u8	status;
+	__be32	data_out_res_cnt;
+	__be32	data_in_res_cnt;
+	__be32	sense_data_len;
+	__be32	resp_data_len;
+	u8	data[0];
+};
+
+#endif /* SCSI_SRP_H */