linux/block/bsg-lib.c

// SPDX-License-Identifier: GPL-2.0-or-later
/*
 *  BSG helper library
 *
 *  Copyright (C) 2008   James Smart, Emulex Corporation
 *  Copyright (C) 2011   Red Hat, Inc.  All rights reserved.
 *  Copyright (C) 2011   Mike Christie
 */
#include <linux/bsg.h>
#include <linux/slab.h>
#include <linux/blk-mq.h>
#include <linux/delay.h>
#include <linux/scatterlist.h>
#include <linux/bsg-lib.h>
#include <linux/export.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/sg.h>

#define uptr64(val) …

struct bsg_set { … };

static int bsg_transport_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
		bool open_for_write, unsigned int timeout)
{ … }

/**
 * bsg_teardown_job - routine to teardown a bsg job
 * @kref: kref inside bsg_job that is to be torn down
 */
static void bsg_teardown_job(struct kref *kref)
{ … }

void bsg_job_put(struct bsg_job *job)
{ … }
EXPORT_SYMBOL_GPL(…);

int bsg_job_get(struct bsg_job *job)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * bsg_job_done - completion routine for bsg requests
 * @job: bsg_job that is complete
 * @result: job reply result
 * @reply_payload_rcv_len: length of payload recvd
 *
 * The LLD should call this when the bsg job has completed.
 */
void bsg_job_done(struct bsg_job *job, int result,
		  unsigned int reply_payload_rcv_len)
{ … }
EXPORT_SYMBOL_GPL(…);

/**
 * bsg_complete - softirq done routine for destroying the bsg requests
 * @rq: BSG request that holds the job to be destroyed
 */
static void bsg_complete(struct request *rq)
{ … }

static int bsg_map_buffer(struct bsg_buffer *buf, struct request *req)
{ … }

/**
 * bsg_prepare_job - create the bsg_job structure for the bsg request
 * @dev: device that is being sent the bsg request
 * @req: BSG request that needs a job structure
 */
static bool bsg_prepare_job(struct device *dev, struct request *req)
{ … }

/**
 * bsg_queue_rq - generic handler for bsg requests
 * @hctx: hardware queue
 * @bd: queue data
 *
 * On error the create_bsg_job function should return a -Exyz error value
 * that will be set to ->result.
 *
 * Drivers/subsys should pass this to the queue init function.
 */
static blk_status_t bsg_queue_rq(struct blk_mq_hw_ctx *hctx,
				 const struct blk_mq_queue_data *bd)
{ … }

/* called right after the request is allocated for the request_queue */
static int bsg_init_rq(struct blk_mq_tag_set *set, struct request *req,
		       unsigned int hctx_idx, unsigned int numa_node)
{ … }

static void bsg_exit_rq(struct blk_mq_tag_set *set, struct request *req,
		       unsigned int hctx_idx)
{ … }

void bsg_remove_queue(struct request_queue *q)
{ … }
EXPORT_SYMBOL_GPL(…);

static enum blk_eh_timer_return bsg_timeout(struct request *rq)
{ … }

static const struct blk_mq_ops bsg_mq_ops = …;

/**
 * bsg_setup_queue - Create and add the bsg hooks so we can receive requests
 * @dev: device to attach bsg device to
 * @name: device to give bsg device
 * @lim: queue limits for the bsg queue
 * @job_fn: bsg job handler
 * @timeout: timeout handler function pointer
 * @dd_job_size: size of LLD data needed for each job
 */
struct request_queue *bsg_setup_queue(struct device *dev, const char *name,
		struct queue_limits *lim, bsg_job_fn *job_fn,
		bsg_timeout_fn *timeout, int dd_job_size)
{ … }
EXPORT_SYMBOL_GPL(…);