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 15 struct request; 16 struct device; 17 struct scatterlist; 18 struct request_queue; 19 20 typedef int (bsg_job_fn) (struct bsg_job *); 21 typedef enum blk_eh_timer_return (bsg_timeout_fn)(struct request *); 22 23 struct bsg_buffer { 24 unsigned int payload_len; 25 int sg_cnt; 26 struct scatterlist *sg_list; 27 }; 28 29 struct bsg_job { 30 struct device *dev; 31 32 struct kref kref; 33 34 unsigned int timeout; 35 36 /* Transport/driver specific request/reply structs */ 37 void *request; 38 void *reply; 39 40 unsigned int request_len; 41 unsigned int reply_len; 42 /* 43 * On entry : reply_len indicates the buffer size allocated for 44 * the reply. 45 * 46 * Upon completion : the message handler must set reply_len 47 * to indicates the size of the reply to be returned to the 48 * caller. 49 */ 50 51 /* DMA payloads for the request/response */ 52 struct bsg_buffer request_payload; 53 struct bsg_buffer reply_payload; 54 55 int result; 56 unsigned int reply_payload_rcv_len; 57 58 /* BIDI support */ 59 struct request *bidi_rq; 60 struct bio *bidi_bio; 61 62 void *dd_data; /* Used for driver-specific storage */ 63 }; 64 65 void bsg_job_done(struct bsg_job *job, int result, 66 unsigned int reply_payload_rcv_len); 67 struct request_queue *bsg_setup_queue(struct device *dev, const char *name, 68 bsg_job_fn *job_fn, bsg_timeout_fn *timeout, int dd_job_size); 69 void bsg_remove_queue(struct request_queue *q); 70 void bsg_job_put(struct bsg_job *job); 71 int __must_check bsg_job_get(struct bsg_job *job); 72 73 #endif 74