IB/iser: iSCSI iSER transport provider header file

/*

 * iSER transport for the Open iSCSI Initiator & iSER transport internals

 *

 * Copyright (C) 2004 Dmitry Yusupov

 * Copyright (C) 2004 Alex Aizman

 * Copyright (C) 2005 Mike Christie

 * based on code maintained by open-iscsi@googlegroups.com

 *

 * Copyright (c) 2004, 2005, 2006 Voltaire, Inc. All rights reserved.

 * Copyright (c) 2005, 2006 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: iscsi_iser.h 7051 2006-05-10 12:29:11Z ogerlitz $

 */

#ifndef __ISCSI_ISER_H__

#define __ISCSI_ISER_H__

#include <linux/types.h>

#include <linux/net.h>

#include <scsi/libiscsi.h>

#include <scsi/scsi_transport_iscsi.h>

#include <linux/wait.h>

#include <linux/sched.h>

#include <linux/list.h>

#include <linux/slab.h>

#include <linux/dma-mapping.h>

#include <linux/mutex.h>

#include <linux/mempool.h>

#include <linux/uio.h>

#include <linux/socket.h>

#include <linux/in.h>

#include <linux/in6.h>

#include <rdma/ib_verbs.h>

#include <rdma/ib_fmr_pool.h>

#include <rdma/rdma_cm.h>

#define DRV_NAME	"iser"

#define PFX		DRV_NAME ": "

#define DRV_VER		"0.1"

#define DRV_DATE	"May 7th, 2006"

#define iser_dbg(fmt, arg...)				\

	do {						\

		if (iser_debug_level > 0)		\

			printk(KERN_DEBUG PFX "%s:" fmt,\

				__func__ , ## arg);	\

	} while (0)

#define iser_err(fmt, arg...)				\

	do {						\

		printk(KERN_ERR PFX "%s:" fmt,          \

		       __func__ , ## arg);		\

	} while (0)

					/* support upto 512KB in one RDMA */

#define ISCSI_ISER_SG_TABLESIZE         (0x80000 >> PAGE_SHIFT)

#define ISCSI_ISER_MAX_LUN		256

#define ISCSI_ISER_MAX_CMD_LEN		16

/* QP settings */

/* Maximal bounds on received asynchronous PDUs */

#define ISER_MAX_RX_MISC_PDUS		4 /* NOOP_IN(2) , ASYNC_EVENT(2)   */

#define ISER_MAX_TX_MISC_PDUS		6 /* NOOP_OUT(2), TEXT(1),         *

					   * SCSI_TMFUNC(2), LOGOUT(1) */

#define ISER_QP_MAX_RECV_DTOS		(ISCSI_XMIT_CMDS_MAX + \

					ISER_MAX_RX_MISC_PDUS    +  \

					ISER_MAX_TX_MISC_PDUS)

/* the max TX (send) WR supported by the iSER QP is defined by                 *

 * max_send_wr = T * (1 + D) + C ; D is how many inflight dataouts we expect   *

 * to have at max for SCSI command. The tx posting & completion handling code  *

 * supports -EAGAIN scheme where tx is suspended till the QP has room for more *

 * send WR. D=8 comes from 64K/8K                                              */

#define ISER_INFLIGHT_DATAOUTS		8

#define ISER_QP_MAX_REQ_DTOS		(ISCSI_XMIT_CMDS_MAX *    \

					(1 + ISER_INFLIGHT_DATAOUTS) + \

					ISER_MAX_TX_MISC_PDUS        + \

					ISER_MAX_RX_MISC_PDUS)

#define ISER_VER			0x10

#define ISER_WSV			0x08

#define ISER_RSV			0x04

struct iser_hdr {

	u8      flags;

	u8      rsvd[3];

	__be32  write_stag; /* write rkey */

	__be64  write_va;

	__be32  read_stag;  /* read rkey */

	__be64  read_va;

} __attribute__((packed));

/* Length of an object name string */

#define ISER_OBJECT_NAME_SIZE		    64

enum iser_ib_conn_state {

	ISER_CONN_INIT,		   /* descriptor allocd, no conn          */

	ISER_CONN_PENDING,	   /* in the process of being established */

	ISER_CONN_UP,		   /* up and running                      */

	ISER_CONN_TERMINATING,	   /* in the process of being terminated  */

	ISER_CONN_DOWN,		   /* shut down                           */

	ISER_CONN_STATES_NUM

};

enum iser_task_status {

	ISER_TASK_STATUS_INIT = 0,

	ISER_TASK_STATUS_STARTED,

	ISER_TASK_STATUS_COMPLETED

};

enum iser_data_dir {

	ISER_DIR_IN = 0,	   /* to initiator */

	ISER_DIR_OUT,		   /* from initiator */

	ISER_DIRS_NUM

};

struct iser_data_buf {

	void               *buf;      /* pointer to the sg list               */

	unsigned int       size;      /* num entries of this sg               */

	unsigned long      data_len;  /* total data len                       */

	unsigned int       dma_nents; /* returned by dma_map_sg               */

	char       	   *copy_buf; /* allocated copy buf for SGs unaligned *

	                               * for rdma which are copied            */

	struct scatterlist sg_single; /* SG-ified clone of a non SG SC or     *

				       * unaligned SG                         */

  };

/* fwd declarations */

struct iser_device;

struct iscsi_iser_conn;

struct iscsi_iser_cmd_task;

struct iser_mem_reg {

	u32  lkey;

	u32  rkey;

	u64  va;

	u64  len;

	void *mem_h;

};

struct iser_regd_buf {

	struct iser_mem_reg     reg;        /* memory registration info        */

	void                    *virt_addr;

	struct iser_device      *device;    /* device->device for dma_unmap    */

	dma_addr_t              dma_addr;   /* if non zero, addr for dma_unmap */

	enum dma_data_direction direction;  /* direction for dma_unmap	       */

	unsigned int            data_size;

	atomic_t                ref_count;  /* refcount, freed when dec to 0   */

};

#define MAX_REGD_BUF_VECTOR_LEN	2

struct iser_dto {

	struct iscsi_iser_cmd_task *ctask;

	struct iscsi_iser_conn     *conn;

	int                        notify_enable;

	/* vector of registered buffers */

	unsigned int               regd_vector_len;

	struct iser_regd_buf       *regd[MAX_REGD_BUF_VECTOR_LEN];

	/* offset into the registered buffer may be specified */

	unsigned int               offset[MAX_REGD_BUF_VECTOR_LEN];

	/* a smaller size may be specified, if 0, then full size is used */

	unsigned int               used_sz[MAX_REGD_BUF_VECTOR_LEN];

};

enum iser_desc_type {

	ISCSI_RX,

	ISCSI_TX_CONTROL ,

	ISCSI_TX_SCSI_COMMAND,

	ISCSI_TX_DATAOUT

};

struct iser_desc {

	struct iser_hdr              iser_header;

	struct iscsi_hdr             iscsi_header;

	struct iser_regd_buf         hdr_regd_buf;

	void                         *data;         /* used by RX & TX_CONTROL */

	struct iser_regd_buf         data_regd_buf; /* used by RX & TX_CONTROL */

	enum   iser_desc_type        type;

	struct iser_dto              dto;

};

struct iser_device {

	struct ib_device             *ib_device;

	struct ib_pd	             *pd;

	struct ib_cq	             *cq;

	struct ib_mr	             *mr;

	struct tasklet_struct	     cq_tasklet;

	struct list_head             ig_list; /* entry in ig devices list */

	int                          refcount;

};

struct iser_conn {

	struct iscsi_iser_conn       *iser_conn; /* iser conn for upcalls  */

	enum iser_ib_conn_state	     state;	    /* rdma connection state   */

	spinlock_t		     lock;	    /* used for state changes  */

	struct iser_device           *device;       /* device context          */

	struct rdma_cm_id            *cma_id;       /* CMA ID		       */

	struct ib_qp	             *qp;           /* QP 		       */

	struct ib_fmr_pool           *fmr_pool;     /* pool of IB FMRs         */

	int                          disc_evt_flag; /* disconn event delivered */

	wait_queue_head_t	     wait;          /* waitq for conn/disconn  */

	atomic_t                     post_recv_buf_count; /* posted rx count   */

	atomic_t                     post_send_buf_count; /* posted tx count   */

	struct work_struct           comperror_work; /* conn term sleepable ctx*/

	char 			     name[ISER_OBJECT_NAME_SIZE];

	struct iser_page_vec         *page_vec;     /* represents SG to fmr maps*

						     * maps serialized as tx is*/

	struct list_head	     conn_list;       /* entry in ig conn list */

};

struct iscsi_iser_conn {

	struct iscsi_conn            *iscsi_conn;/* ptr to iscsi conn */

	struct iser_conn             *ib_conn;   /* iSER IB conn      */

	rwlock_t		     lock;

};

struct iscsi_iser_cmd_task {

	struct iser_desc             desc;

	struct iscsi_iser_conn	     *iser_conn;

	int			     rdma_data_count;/* RDMA bytes           */

	enum iser_task_status 	     status;

	int                          command_sent;  /* set if command  sent  */

	int                          dir[ISER_DIRS_NUM];      /* set if dir use*/

	struct iser_regd_buf         rdma_regd[ISER_DIRS_NUM];/* regd rdma buf */

	struct iser_data_buf         data[ISER_DIRS_NUM];     /* orig. data des*/

	struct iser_data_buf         data_copy[ISER_DIRS_NUM];/* contig. copy  */

};

struct iser_page_vec {

	u64 *pages;

	int length;

	int offset;

	int data_size;

};

struct iser_global {

	struct mutex      device_list_mutex;/*                   */

	struct list_head  device_list;	     /* all iSER devices */

	struct mutex      connlist_mutex;

	struct list_head  connlist;		/* all iSER IB connections */

	kmem_cache_t *desc_cache;

};

extern struct iser_global ig;

extern int iser_debug_level;

/* allocate connection resources needed for rdma functionality */

int iser_conn_set_full_featured_mode(struct iscsi_conn *conn);

int iser_send_control(struct iscsi_conn      *conn,

		      struct iscsi_mgmt_task *mtask);

int iser_send_command(struct iscsi_conn      *conn,

		      struct iscsi_cmd_task  *ctask);

int iser_send_data_out(struct iscsi_conn     *conn,

		       struct iscsi_cmd_task *ctask,

		       struct iscsi_data          *hdr);

void iscsi_iser_recv(struct iscsi_conn *conn,

		     struct iscsi_hdr       *hdr,

		     char                   *rx_data,

		     int                    rx_data_len);

int  iser_conn_init(struct iser_conn **ib_conn);

void iser_conn_terminate(struct iser_conn *ib_conn);

void iser_conn_release(struct iser_conn *ib_conn);

void iser_rcv_completion(struct iser_desc *desc,

			 unsigned long    dto_xfer_len);

void iser_snd_completion(struct iser_desc *desc);

void iser_ctask_rdma_init(struct iscsi_iser_cmd_task     *ctask);

void iser_ctask_rdma_finalize(struct iscsi_iser_cmd_task *ctask);

void iser_dto_buffs_release(struct iser_dto *dto);

int  iser_regd_buff_release(struct iser_regd_buf *regd_buf);

void iser_reg_single(struct iser_device      *device,

		     struct iser_regd_buf    *regd_buf,

		     enum dma_data_direction direction);

int  iser_start_rdma_unaligned_sg(struct iscsi_iser_cmd_task    *ctask,

				  enum iser_data_dir            cmd_dir);

void iser_finalize_rdma_unaligned_sg(struct iscsi_iser_cmd_task *ctask,

				     enum iser_data_dir         cmd_dir);

int  iser_reg_rdma_mem(struct iscsi_iser_cmd_task *ctask,

		       enum   iser_data_dir        cmd_dir);

int  iser_connect(struct iser_conn   *ib_conn,

		  struct sockaddr_in *src_addr,

		  struct sockaddr_in *dst_addr,

		  int                non_blocking);

int  iser_reg_page_vec(struct iser_conn     *ib_conn,

		       struct iser_page_vec *page_vec,

		       struct iser_mem_reg  *mem_reg);

void iser_unreg_mem(struct iser_mem_reg *mem_reg);

int  iser_post_recv(struct iser_desc *rx_desc);

int  iser_post_send(struct iser_desc *tx_desc);

int iser_conn_state_comp(struct iser_conn *ib_conn,

			 enum iser_ib_conn_state comp);

#endif