/* SPDX-License-Identifier: GPL-2.0+ WITH Linux-syscall-note */
/*
 *  FC Transport BSG Interface
 *
 *  Copyright (C) 2008   James Smart, Emulex Corporation
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 *
 */

#ifndef SCSI_BSG_FC_H
#define SCSI_BSG_FC_H

/*
 * This file intended to be included by both kernel and user space
 */

/*
 * FC Transport SGIO v4 BSG Message Support
 */

/* Default BSG request timeout (in seconds) */
#define FC_DEFAULT_BSG_TIMEOUT          (10 * HZ)


/*
 * Request Message Codes supported by the FC Transport
 */

/* define the class masks for the message codes */
#define FC_BSG_CLS_MASK         0xF0000000      /* find object class */
#define FC_BSG_HST_MASK         0x80000000      /* fc host class */
#define FC_BSG_RPT_MASK         0x40000000      /* fc rport class */

        /* fc_host Message Codes */
#define FC_BSG_HST_ADD_RPORT            (FC_BSG_HST_MASK | 0x00000001)
#define FC_BSG_HST_DEL_RPORT            (FC_BSG_HST_MASK | 0x00000002)
#define FC_BSG_HST_ELS_NOLOGIN          (FC_BSG_HST_MASK | 0x00000003)
#define FC_BSG_HST_CT                   (FC_BSG_HST_MASK | 0x00000004)
#define FC_BSG_HST_VENDOR               (FC_BSG_HST_MASK | 0x000000FF)

        /* fc_rport Message Codes */
#define FC_BSG_RPT_ELS                  (FC_BSG_RPT_MASK | 0x00000001)
#define FC_BSG_RPT_CT                   (FC_BSG_RPT_MASK | 0x00000002)



/*
 * FC Address Identifiers in Message Structures :
 *
 *   Whenever a command payload contains a FC Address Identifier
 *   (aka port_id), the value is effectively in big-endian
 *   order, thus the array elements are decoded as follows:
 *     element [0] is bits 23:16 of the FC Address Identifier
 *     element [1] is bits 15:8 of the FC Address Identifier
 *     element [2] is bits 7:0 of the FC Address Identifier
 */


/*
 * FC Host Messages
 */

/* FC_BSG_HST_ADDR_PORT : */

/* Request:
 * This message requests the FC host to login to the remote port
 * at the specified N_Port_Id.  The remote port is to be enumerated
 * with the transport upon completion of the login.
 */
struct fc_bsg_host_add_rport {
        uint8_t         reserved;

        /* FC Address Identier of the remote port to login to */
        uint8_t         port_id[3];
};

/* Response:
 * There is no additional response data - fc_bsg_reply->result is sufficient
 */


/* FC_BSG_HST_DEL_RPORT : */

/* Request:
 * This message requests the FC host to remove an enumerated
 * remote port and to terminate the login to it.
 *
 * Note: The driver is free to reject this request if it desires to
 * remain logged in with the remote port.
 */
struct fc_bsg_host_del_rport {
        uint8_t         reserved;

        /* FC Address Identier of the remote port to logout of */
        uint8_t         port_id[3];
};

/* Response:
 * There is no additional response data - fc_bsg_reply->result is sufficient
 */


/* FC_BSG_HST_ELS_NOLOGIN : */

/* Request:
 * This message requests the FC_Host to send an ELS to a specific
 * N_Port_ID. The host does not need to log into the remote port,
 * nor does it need to enumerate the rport for further traffic
 * (although, the FC host is free to do so if it desires).
 */
struct fc_bsg_host_els {
        /*
         * ELS Command Code being sent (must be the same as byte 0
         * of the payload)
         */
        uint8_t         command_code;

        /* FC Address Identier of the remote port to send the ELS to */
        uint8_t         port_id[3];
};

/* Response:
 */
/* fc_bsg_ctels_reply->status values */
#define FC_CTELS_STATUS_OK      0x00000000
#define FC_CTELS_STATUS_REJECT  0x00000001
#define FC_CTELS_STATUS_P_RJT   0x00000002
#define FC_CTELS_STATUS_F_RJT   0x00000003
#define FC_CTELS_STATUS_P_BSY   0x00000004
#define FC_CTELS_STATUS_F_BSY   0x00000006
struct fc_bsg_ctels_reply {
        /*
         * Note: An ELS LS_RJT may be reported in 2 ways:
         *  a) A status of FC_CTELS_STATUS_OK is returned. The caller
         *     is to look into the ELS receive payload to determine
         *     LS_ACC or LS_RJT (by contents of word 0). The reject
         *     data will be in word 1.
         *  b) A status of FC_CTELS_STATUS_REJECT is returned, The
         *     rjt_data field will contain valid data.
         *
         * Note: ELS LS_ACC is determined by an FC_CTELS_STATUS_OK, and
         *   the receive payload word 0 indicates LS_ACC
         *   (e.g. value is 0x02xxxxxx).
         *
         * Note: Similarly, a CT Reject may be reported in 2 ways:
         *  a) A status of FC_CTELS_STATUS_OK is returned. The caller
         *     is to look into the CT receive payload to determine
         *     Accept or Reject (by contents of word 2). The reject
         *     data will be in word 3.
         *  b) A status of FC_CTELS_STATUS_REJECT is returned, The
         *     rjt_data field will contain valid data.
         *
         * Note: x_RJT/BSY status will indicae that the rjt_data field
         *   is valid and contains the reason/explanation values.
         */
        uint32_t        status;         /* See FC_CTELS_STATUS_xxx */

        /* valid if status is not FC_CTELS_STATUS_OK */
        struct  {
                uint8_t action;         /* fragment_id for CT REJECT */
                uint8_t reason_code;
                uint8_t reason_explanation;
                uint8_t vendor_unique;
        } rjt_data;
};


/* FC_BSG_HST_CT : */

/* Request:
 * This message requests that a CT Request be performed with the
 * indicated N_Port_ID. The driver is responsible for logging in with
 * the fabric and/or N_Port_ID, etc as per FC rules. This request does
 * not mandate that the driver must enumerate the destination in the
 * transport. The driver is allowed to decide whether to enumerate it,
 * and whether to tear it down after the request.
 */
struct fc_bsg_host_ct {
        uint8_t         reserved;

        /* FC Address Identier of the remote port to send the ELS to */
        uint8_t         port_id[3];

        /*
         * We need words 0-2 of the generic preamble for the LLD's
         */
        uint32_t        preamble_word0; /* revision & IN_ID */
        uint32_t        preamble_word1; /* GS_Type, GS_SubType, Options, Rsvd */
        uint32_t        preamble_word2; /* Cmd Code, Max Size */

};
/* Response:
 *
 * The reply structure is an fc_bsg_ctels_reply structure
 */


/* FC_BSG_HST_VENDOR : */

/* Request:
 * Note: When specifying vendor_id, be sure to read the Vendor Type and ID
 *   formatting requirements specified in scsi_netlink.h
 */
struct fc_bsg_host_vendor {
        /*
         * Identifies the vendor that the message is formatted for. This
         * should be the recipient of the message.
         */
        uint64_t vendor_id;

        /* start of vendor command area */
        uint32_t vendor_cmd[0];
};

/* Response:
 */
struct fc_bsg_host_vendor_reply {
        /* start of vendor response area */
        uint32_t vendor_rsp[0];
};



/*
 * FC Remote Port Messages
 */

/* FC_BSG_RPT_ELS : */

/* Request:
 * This message requests that an ELS be performed with the rport.
 */
struct fc_bsg_rport_els {
        /*
         * ELS Command Code being sent (must be the same as
         * byte 0 of the payload)
         */
        uint8_t els_code;
};

/* Response:
 *
 * The reply structure is an fc_bsg_ctels_reply structure
 */


/* FC_BSG_RPT_CT : */

/* Request:
 * This message requests that a CT Request be performed with the rport.
 */
struct fc_bsg_rport_ct {
        /*
         * We need words 0-2 of the generic preamble for the LLD's
         */
        uint32_t        preamble_word0; /* revision & IN_ID */
        uint32_t        preamble_word1; /* GS_Type, GS_SubType, Options, Rsvd */
        uint32_t        preamble_word2; /* Cmd Code, Max Size */
};
/* Response:
 *
 * The reply structure is an fc_bsg_ctels_reply structure
 */




/* request (CDB) structure of the sg_io_v4 */
struct fc_bsg_request {
        uint32_t msgcode;
        union {
                struct fc_bsg_host_add_rport    h_addrport;
                struct fc_bsg_host_del_rport    h_delrport;
                struct fc_bsg_host_els          h_els;
                struct fc_bsg_host_ct           h_ct;
                struct fc_bsg_host_vendor       h_vendor;

                struct fc_bsg_rport_els         r_els;
                struct fc_bsg_rport_ct          r_ct;
        } rqst_data;
} __attribute__((packed));


/* response (request sense data) structure of the sg_io_v4 */
struct fc_bsg_reply {
        /*
         * The completion result. Result exists in two forms:
         *  if negative, it is an -Exxx system errno value. There will
         *    be no further reply information supplied.
         *  else, it's the 4-byte scsi error result, with driver, host,
         *    msg and status fields. The per-msgcode reply structure
         *    will contain valid data.
         */
        uint32_t result;

        /* If there was reply_payload, how much was recevied ? */
        uint32_t reply_payload_rcv_len;

        union {
                struct fc_bsg_host_vendor_reply         vendor_reply;

                struct fc_bsg_ctels_reply               ctels_reply;
        } reply_data;
};


#endif /* SCSI_BSG_FC_H */