GNU Linux-libre 5.19-rc6-gnu
[releases.git] / drivers / scsi / scsi_bsg.c
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/bsg.h>
3 #include <scsi/scsi.h>
4 #include <scsi/scsi_ioctl.h>
5 #include <scsi/scsi_cmnd.h>
6 #include <scsi/scsi_device.h>
7 #include <scsi/sg.h>
8 #include "scsi_priv.h"
9
10 #define uptr64(val) ((void __user *)(uintptr_t)(val))
11
12 static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
13                 fmode_t mode, unsigned int timeout)
14 {
15         struct scsi_cmnd *scmd;
16         struct request *rq;
17         struct bio *bio;
18         int ret;
19
20         if (hdr->protocol != BSG_PROTOCOL_SCSI  ||
21             hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_CMD)
22                 return -EINVAL;
23         if (hdr->dout_xfer_len && hdr->din_xfer_len) {
24                 pr_warn_once("BIDI support in bsg has been removed.\n");
25                 return -EOPNOTSUPP;
26         }
27
28         rq = scsi_alloc_request(q, hdr->dout_xfer_len ?
29                                 REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
30         if (IS_ERR(rq))
31                 return PTR_ERR(rq);
32         rq->timeout = timeout;
33
34         scmd = blk_mq_rq_to_pdu(rq);
35         scmd->cmd_len = hdr->request_len;
36         if (scmd->cmd_len > sizeof(scmd->cmnd)) {
37                 ret = -EINVAL;
38                 goto out_put_request;
39         }
40
41         ret = -EFAULT;
42         if (copy_from_user(scmd->cmnd, uptr64(hdr->request), scmd->cmd_len))
43                 goto out_put_request;
44         ret = -EPERM;
45         if (!scsi_cmd_allowed(scmd->cmnd, mode))
46                 goto out_put_request;
47
48         ret = 0;
49         if (hdr->dout_xfer_len) {
50                 ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->dout_xferp),
51                                 hdr->dout_xfer_len, GFP_KERNEL);
52         } else if (hdr->din_xfer_len) {
53                 ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->din_xferp),
54                                 hdr->din_xfer_len, GFP_KERNEL);
55         }
56
57         if (ret)
58                 goto out_put_request;
59
60         bio = rq->bio;
61         blk_execute_rq(rq, !(hdr->flags & BSG_FLAG_Q_AT_TAIL));
62
63         /*
64          * fill in all the output members
65          */
66         hdr->device_status = scmd->result & 0xff;
67         hdr->transport_status = host_byte(scmd->result);
68         hdr->driver_status = 0;
69         if (scsi_status_is_check_condition(scmd->result))
70                 hdr->driver_status = DRIVER_SENSE;
71         hdr->info = 0;
72         if (hdr->device_status || hdr->transport_status || hdr->driver_status)
73                 hdr->info |= SG_INFO_CHECK;
74         hdr->response_len = 0;
75
76         if (scmd->sense_len && hdr->response) {
77                 int len = min_t(unsigned int, hdr->max_response_len,
78                                 scmd->sense_len);
79
80                 if (copy_to_user(uptr64(hdr->response), scmd->sense_buffer,
81                                  len))
82                         ret = -EFAULT;
83                 else
84                         hdr->response_len = len;
85         }
86
87         if (rq_data_dir(rq) == READ)
88                 hdr->din_resid = scmd->resid_len;
89         else
90                 hdr->dout_resid = scmd->resid_len;
91
92         blk_rq_unmap_user(bio);
93
94 out_put_request:
95         blk_mq_free_request(rq);
96         return ret;
97 }
98
99 struct bsg_device *scsi_bsg_register_queue(struct scsi_device *sdev)
100 {
101         return bsg_register_queue(sdev->request_queue, &sdev->sdev_gendev,
102                         dev_name(&sdev->sdev_gendev), scsi_bsg_sg_io_fn);
103 }