linux_dsm_epyc7002/include/linux/bsg-lib.h
Christoph Hellwig 972248e911 scsi: bsg-lib: handle bidi requests without block layer help
We can just stash away the second request in struct bsg_job instead of
using the block layer req->next_rq field, allowing for the eventual removal
of the latter.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2019-02-05 21:27:40 -05:00

88 lines
2.4 KiB
C

/*
* BSG helper library
*
* Copyright (C) 2008 James Smart, Emulex Corporation
* Copyright (C) 2011 Red Hat, Inc. All rights reserved.
* Copyright (C) 2011 Mike Christie
*
* 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 _BLK_BSG_
#define _BLK_BSG_
#include <linux/blkdev.h>
#include <scsi/scsi_request.h>
struct request;
struct device;
struct scatterlist;
struct request_queue;
typedef int (bsg_job_fn) (struct bsg_job *);
typedef enum blk_eh_timer_return (bsg_timeout_fn)(struct request *);
struct bsg_buffer {
unsigned int payload_len;
int sg_cnt;
struct scatterlist *sg_list;
};
struct bsg_job {
struct device *dev;
struct kref kref;
unsigned int timeout;
/* Transport/driver specific request/reply structs */
void *request;
void *reply;
unsigned int request_len;
unsigned int reply_len;
/*
* On entry : reply_len indicates the buffer size allocated for
* the reply.
*
* Upon completion : the message handler must set reply_len
* to indicates the size of the reply to be returned to the
* caller.
*/
/* DMA payloads for the request/response */
struct bsg_buffer request_payload;
struct bsg_buffer reply_payload;
int result;
unsigned int reply_payload_rcv_len;
/* BIDI support */
struct request *bidi_rq;
struct bio *bidi_bio;
void *dd_data; /* Used for driver-specific storage */
};
void bsg_job_done(struct bsg_job *job, int result,
unsigned int reply_payload_rcv_len);
struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
bsg_job_fn *job_fn, bsg_timeout_fn *timeout, int dd_job_size);
void bsg_remove_queue(struct request_queue *q);
void bsg_job_put(struct bsg_job *job);
int __must_check bsg_job_get(struct bsg_job *job);
#endif