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_request *sreq; 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 = blk_get_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 ret = -ENOMEM; 35 sreq = scsi_req(rq); 36 sreq->cmd_len = hdr->request_len; 37 if (sreq->cmd_len > BLK_MAX_CDB) { 38 sreq->cmd = kzalloc(sreq->cmd_len, GFP_KERNEL); 39 if (!sreq->cmd) 40 goto out_put_request; 41 } 42 43 ret = -EFAULT; 44 if (copy_from_user(sreq->cmd, uptr64(hdr->request), sreq->cmd_len)) 45 goto out_free_cmd; 46 ret = -EPERM; 47 if (!scsi_cmd_allowed(sreq->cmd, mode)) 48 goto out_free_cmd; 49 50 ret = 0; 51 if (hdr->dout_xfer_len) { 52 ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->dout_xferp), 53 hdr->dout_xfer_len, GFP_KERNEL); 54 } else if (hdr->din_xfer_len) { 55 ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->din_xferp), 56 hdr->din_xfer_len, GFP_KERNEL); 57 } 58 59 if (ret) 60 goto out_free_cmd; 61 62 bio = rq->bio; 63 blk_execute_rq(NULL, rq, !(hdr->flags & BSG_FLAG_Q_AT_TAIL)); 64 65 /* 66 * fill in all the output members 67 */ 68 hdr->device_status = sreq->result & 0xff; 69 hdr->transport_status = host_byte(sreq->result); 70 hdr->driver_status = 0; 71 if (scsi_status_is_check_condition(sreq->result)) 72 hdr->driver_status = DRIVER_SENSE; 73 hdr->info = 0; 74 if (hdr->device_status || hdr->transport_status || hdr->driver_status) 75 hdr->info |= SG_INFO_CHECK; 76 hdr->response_len = 0; 77 78 if (sreq->sense_len && hdr->response) { 79 int len = min_t(unsigned int, hdr->max_response_len, 80 sreq->sense_len); 81 82 if (copy_to_user(uptr64(hdr->response), sreq->sense, len)) 83 ret = -EFAULT; 84 else 85 hdr->response_len = len; 86 } 87 88 if (rq_data_dir(rq) == READ) 89 hdr->din_resid = sreq->resid_len; 90 else 91 hdr->dout_resid = sreq->resid_len; 92 93 blk_rq_unmap_user(bio); 94 95 out_free_cmd: 96 scsi_req_free_cmd(scsi_req(rq)); 97 out_put_request: 98 blk_put_request(rq); 99 return ret; 100 } 101 102 struct bsg_device *scsi_bsg_register_queue(struct scsi_device *sdev) 103 { 104 return bsg_register_queue(sdev->request_queue, &sdev->sdev_gendev, 105 dev_name(&sdev->sdev_gendev), scsi_bsg_sg_io_fn); 106 } 107