scsi: qedi: Add QLogic FastLinQ offload iSCSI driver framework.

The QLogic FastLinQ Driver for iSCSI (qedi) is the iSCSI specific module
for 41000 Series Converged Network Adapters by QLogic.

This patch consists of following changes:

  - MAINTAINERS Makefile and Kconfig changes for qedi,
  - PCI driver registration,
  - iSCSI host level initialization,
  - Debugfs and log level infrastructure.

The following indiviual changes are merged into this commit:

  qedi: Add LL2 iSCSI interface for offload iSCSI.
  qedi: Add support for iSCSI session management.
  qedi: Add support for data path.

Signed-off-by: Nilesh Javali <nilesh.javali@cavium.com>
Signed-off-by: Adheer Chandravanshi <adheer.chandravanshi@qlogic.com>
Signed-off-by: Chad Dupuis <chad.dupuis@cavium.com>
Signed-off-by: Saurav Kashyap <saurav.kashyap@cavium.com>
Signed-off-by: Arun Easi <arun.easi@cavium.com>
Signed-off-by: Manish Rangankar <manish.rangankar@cavium.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

1 files changed, 232 insertions, 0 deletions

diff --git a/drivers/scsi/qedi/qedi_iscsi.h b/drivers/scsi/qedi/qedi_iscsi.h
new file mode 100644
index 000000000000..d3c06bbddb4e
--- /dev/null
+++ b/drivers/scsi/qedi/qedi_iscsi.h
@@ -0,0 +1,232 @@
+/*
+ * QLogic iSCSI Offload Driver
+ * Copyright (c) 2016 Cavium Inc.
+ *
+ * This software is available 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.
+ */
+
+#ifndef _QEDI_ISCSI_H_
+#define _QEDI_ISCSI_H_
+
+#include <linux/socket.h>
+#include <linux/completion.h>
+#include "qedi.h"
+
+#define ISCSI_MAX_SESS_PER_HBA	4096
+
+#define DEF_KA_TIMEOUT		7200000
+#define DEF_KA_INTERVAL		10000
+#define DEF_KA_MAX_PROBE_COUNT	10
+#define DEF_TOS			0
+#define DEF_TTL			0xfe
+#define DEF_SND_SEQ_SCALE	0
+#define DEF_RCV_BUF		0xffff
+#define DEF_SND_BUF		0xffff
+#define DEF_SEED		0
+#define DEF_MAX_RT_TIME		8000
+#define DEF_MAX_DA_COUNT        2
+#define DEF_SWS_TIMER		1000
+#define DEF_MAX_CWND		2
+#define DEF_PATH_MTU		1500
+#define DEF_MSS			1460
+#define DEF_LL2_MTU		1560
+#define JUMBO_MTU		9000
+
+#define MIN_MTU         576 /* rfc 793 */
+#define IPV4_HDR_LEN    20
+#define IPV6_HDR_LEN    40
+#define TCP_HDR_LEN     20
+#define TCP_OPTION_LEN  12
+#define VLAN_LEN         4
+
+enum {
+	EP_STATE_IDLE                   = 0x0,
+	EP_STATE_ACQRCONN_START         = 0x1,
+	EP_STATE_ACQRCONN_COMPL         = 0x2,
+	EP_STATE_OFLDCONN_START         = 0x4,
+	EP_STATE_OFLDCONN_COMPL         = 0x8,
+	EP_STATE_DISCONN_START          = 0x10,
+	EP_STATE_DISCONN_COMPL          = 0x20,
+	EP_STATE_CLEANUP_START          = 0x40,
+	EP_STATE_CLEANUP_CMPL           = 0x80,
+	EP_STATE_TCP_FIN_RCVD           = 0x100,
+	EP_STATE_TCP_RST_RCVD           = 0x200,
+	EP_STATE_LOGOUT_SENT            = 0x400,
+	EP_STATE_LOGOUT_RESP_RCVD       = 0x800,
+	EP_STATE_CLEANUP_FAILED         = 0x1000,
+	EP_STATE_OFLDCONN_FAILED        = 0x2000,
+	EP_STATE_CONNECT_FAILED         = 0x4000,
+	EP_STATE_DISCONN_TIMEDOUT       = 0x8000,
+};
+
+struct qedi_conn;
+
+struct qedi_endpoint {
+	struct qedi_ctx *qedi;
+	u32 dst_addr[4];
+	u32 src_addr[4];
+	u16 src_port;
+	u16 dst_port;
+	u16 vlan_id;
+	u16 pmtu;
+	u8 src_mac[ETH_ALEN];
+	u8 dst_mac[ETH_ALEN];
+	u8 ip_type;
+	int state;
+	wait_queue_head_t ofld_wait;
+	wait_queue_head_t tcp_ofld_wait;
+	u32 iscsi_cid;
+	/* identifier of the connection from qed */
+	u32 handle;
+	u32 fw_cid;
+	void __iomem *p_doorbell;
+
+	/* Send queue management */
+	struct iscsi_wqe *sq;
+	dma_addr_t sq_dma;
+
+	u16 sq_prod_idx;
+	u16 fw_sq_prod_idx;
+	u16 sq_con_idx;
+	u32 sq_mem_size;
+
+	void *sq_pbl;
+	dma_addr_t sq_pbl_dma;
+	u32 sq_pbl_size;
+	struct qedi_conn *conn;
+	struct work_struct offload_work;
+};
+
+#define QEDI_SQ_WQES_MIN	16
+
+struct qedi_io_bdt {
+	struct iscsi_sge *sge_tbl;
+	dma_addr_t sge_tbl_dma;
+	u16 sge_valid;
+};
+
+/**
+ * struct generic_pdu_resc - login pdu resource structure
+ *
+ * @req_buf:            driver buffer used to stage payload associated with
+ *                      the login request
+ * @req_dma_addr:       dma address for iscsi login request payload buffer
+ * @req_buf_size:       actual login request payload length
+ * @req_wr_ptr:         pointer into login request buffer when next data is
+ *                      to be written
+ * @resp_hdr:           iscsi header where iscsi login response header is to
+ *                      be recreated
+ * @resp_buf:           buffer to stage login response payload
+ * @resp_dma_addr:      login response payload buffer dma address
+ * @resp_buf_size:      login response paylod length
+ * @resp_wr_ptr:        pointer into login response buffer when next data is
+ *                      to be written
+ * @req_bd_tbl:         iscsi login request payload BD table
+ * @req_bd_dma:         login request BD table dma address
+ * @resp_bd_tbl:        iscsi login response payload BD table
+ * @resp_bd_dma:        login request BD table dma address
+ *
+ * following structure defines buffer info for generic pdus such as iSCSI Login,
+ *      Logout and NOP
+ */
+struct generic_pdu_resc {
+	char *req_buf;
+	dma_addr_t req_dma_addr;
+	u32 req_buf_size;
+	char *req_wr_ptr;
+	struct iscsi_hdr resp_hdr;
+	char *resp_buf;
+	dma_addr_t resp_dma_addr;
+	u32 resp_buf_size;
+	char *resp_wr_ptr;
+	char *req_bd_tbl;
+	dma_addr_t req_bd_dma;
+	char *resp_bd_tbl;
+	dma_addr_t resp_bd_dma;
+};
+
+struct qedi_conn {
+	struct iscsi_cls_conn *cls_conn;
+	struct qedi_ctx *qedi;
+	struct qedi_endpoint *ep;
+	struct list_head active_cmd_list;
+	spinlock_t list_lock;		/* internal conn lock */
+	u32 active_cmd_count;
+	u32 cmd_cleanup_req;
+	u32 cmd_cleanup_cmpl;
+
+	u32 iscsi_conn_id;
+	int itt;
+	int abrt_conn;
+#define QEDI_CID_RESERVED	0x5AFF
+	u32 fw_cid;
+	/*
+	 * Buffer for login negotiation process
+	 */
+	struct generic_pdu_resc gen_pdu;
+
+	struct list_head tmf_work_list;
+	wait_queue_head_t wait_queue;
+	spinlock_t tmf_work_lock;	/* tmf work lock */
+	unsigned long flags;
+#define QEDI_CONN_FW_CLEANUP	1
+};
+
+struct qedi_cmd {
+	struct list_head io_cmd;
+	bool io_cmd_in_list;
+	struct iscsi_hdr hdr;
+	struct qedi_conn *conn;
+	struct scsi_cmnd *scsi_cmd;
+	struct scatterlist *sg;
+	struct qedi_io_bdt io_tbl;
+	struct iscsi_task_context request;
+	unsigned char *sense_buffer;
+	dma_addr_t sense_buffer_dma;
+	u16 task_id;
+
+	/* field populated for tmf work queue */
+	struct iscsi_task *task;
+	struct work_struct tmf_work;
+	int state;
+#define CLEANUP_WAIT	1
+#define CLEANUP_RECV	2
+#define CLEANUP_WAIT_FAILED	3
+#define CLEANUP_NOT_REQUIRED	4
+#define LUN_RESET_RESPONSE_RECEIVED	5
+#define RESPONSE_RECEIVED	6
+
+	int type;
+#define TYPEIO		1
+#define TYPERESET	2
+
+	struct qedi_work_map *list_tmf_work;
+	/* slowpath management */
+	bool use_slowpath;
+
+	struct iscsi_tm_rsp *tmf_resp_buf;
+	struct qedi_work cqe_work;
+};
+
+struct qedi_work_map {
+	struct list_head list;
+	struct qedi_cmd *qedi_cmd;
+	int rtid;
+
+	int state;
+#define QEDI_WORK_QUEUED	1
+#define QEDI_WORK_SCHEDULED	2
+#define QEDI_WORK_EXIT		3
+
+	struct work_struct *ptr_tmf_work;
+};
+
+#define qedi_set_itt(task_id, itt) ((u32)(((task_id) & 0xffff) | ((itt) << 16)))
+#define qedi_get_itt(cqe) (cqe.iscsi_hdr.cmd.itt >> 16)
+
+#define QEDI_OFLD_WAIT_STATE(q) ((q)->state == EP_STATE_OFLDCONN_FAILED || \
+				(q)->state == EP_STATE_OFLDCONN_COMPL)
+
+#endif /* _QEDI_ISCSI_H_ */