LXR linux/include/linux/bsg-lib.h

   1/* SPDX-License-Identifier: GPL-2.0-or-later */
   2/*
   3 *  BSG helper library
   4 *
   5 *  Copyright (C) 2008   James Smart, Emulex Corporation
   6 *  Copyright (C) 2011   Red Hat, Inc.  All rights reserved.
   7 *  Copyright (C) 2011   Mike Christie
   8 */
   9#ifndef _BLK_BSG_
  10#define _BLK_BSG_
  11
  12#include <linux/blkdev.h>
  13#include <scsi/scsi_request.h>
  14
  15struct bsg_job;
  16struct request;
  17struct device;
  18struct scatterlist;
  19struct request_queue;
  20
  21typedef int (bsg_job_fn) (struct bsg_job *);
  22typedef enum blk_eh_timer_return (bsg_timeout_fn)(struct request *);
  23
  24struct bsg_buffer {
  25        unsigned int payload_len;
  26        int sg_cnt;
  27        struct scatterlist *sg_list;
  28};
  29
  30struct bsg_job {
  31        struct device *dev;
  32
  33        struct kref kref;
  34
  35        unsigned int timeout;
  36
  37        /* Transport/driver specific request/reply structs */
  38        void *request;
  39        void *reply;
  40
  41        unsigned int request_len;
  42        unsigned int reply_len;
  43        /*
  44         * On entry : reply_len indicates the buffer size allocated for
  45         * the reply.
  46         *
  47         * Upon completion : the message handler must set reply_len
  48         *  to indicates the size of the reply to be returned to the
  49         *  caller.
  50         */
  51
  52        /* DMA payloads for the request/response */
  53        struct bsg_buffer request_payload;
  54        struct bsg_buffer reply_payload;
  55
  56        int result;
  57        unsigned int reply_payload_rcv_len;
  58
  59        /* BIDI support */
  60        struct request *bidi_rq;
  61        struct bio *bidi_bio;
  62
  63        void *dd_data;          /* Used for driver-specific storage */
  64};
  65
  66void bsg_job_done(struct bsg_job *job, int result,
  67                  unsigned int reply_payload_rcv_len);
  68struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
  69                bsg_job_fn *job_fn, bsg_timeout_fn *timeout, int dd_job_size);
  70void bsg_remove_queue(struct request_queue *q);
  71void bsg_job_put(struct bsg_job *job);
  72int __must_check bsg_job_get(struct bsg_job *job);
  73
  74#endif
  75