https://github.com/torvalds/linux
Tip revision: 6613476e225e090cc9aad49be7fa504e290dd33d authored by Linus Torvalds on 21 January 2024, 22:11:32 UTC
Linux 6.8-rc1
Linux 6.8-rc1
Tip revision: 6613476
scsi_bsg.c
// SPDX-License-Identifier: GPL-2.0
#include <linux/bsg.h>
#include <scsi/scsi.h>
#include <scsi/scsi_ioctl.h>
#include <scsi/scsi_cmnd.h>
#include <scsi/scsi_device.h>
#include <scsi/sg.h>
#include "scsi_priv.h"
#define uptr64(val) ((void __user *)(uintptr_t)(val))
static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
bool open_for_write, unsigned int timeout)
{
struct scsi_cmnd *scmd;
struct request *rq;
struct bio *bio;
int ret;
if (hdr->protocol != BSG_PROTOCOL_SCSI ||
hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_CMD)
return -EINVAL;
if (hdr->dout_xfer_len && hdr->din_xfer_len) {
pr_warn_once("BIDI support in bsg has been removed.\n");
return -EOPNOTSUPP;
}
rq = scsi_alloc_request(q, hdr->dout_xfer_len ?
REQ_OP_DRV_OUT : REQ_OP_DRV_IN, 0);
if (IS_ERR(rq))
return PTR_ERR(rq);
rq->timeout = timeout;
scmd = blk_mq_rq_to_pdu(rq);
scmd->cmd_len = hdr->request_len;
if (scmd->cmd_len > sizeof(scmd->cmnd)) {
ret = -EINVAL;
goto out_put_request;
}
ret = -EFAULT;
if (copy_from_user(scmd->cmnd, uptr64(hdr->request), scmd->cmd_len))
goto out_put_request;
ret = -EPERM;
if (!scsi_cmd_allowed(scmd->cmnd, open_for_write))
goto out_put_request;
ret = 0;
if (hdr->dout_xfer_len) {
ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->dout_xferp),
hdr->dout_xfer_len, GFP_KERNEL);
} else if (hdr->din_xfer_len) {
ret = blk_rq_map_user(rq->q, rq, NULL, uptr64(hdr->din_xferp),
hdr->din_xfer_len, GFP_KERNEL);
}
if (ret)
goto out_put_request;
bio = rq->bio;
blk_execute_rq(rq, !(hdr->flags & BSG_FLAG_Q_AT_TAIL));
/*
* fill in all the output members
*/
hdr->device_status = scmd->result & 0xff;
hdr->transport_status = host_byte(scmd->result);
hdr->driver_status = 0;
if (scsi_status_is_check_condition(scmd->result))
hdr->driver_status = DRIVER_SENSE;
hdr->info = 0;
if (hdr->device_status || hdr->transport_status || hdr->driver_status)
hdr->info |= SG_INFO_CHECK;
hdr->response_len = 0;
if (scmd->sense_len && hdr->response) {
int len = min_t(unsigned int, hdr->max_response_len,
scmd->sense_len);
if (copy_to_user(uptr64(hdr->response), scmd->sense_buffer,
len))
ret = -EFAULT;
else
hdr->response_len = len;
}
if (rq_data_dir(rq) == READ)
hdr->din_resid = scmd->resid_len;
else
hdr->dout_resid = scmd->resid_len;
blk_rq_unmap_user(bio);
out_put_request:
blk_mq_free_request(rq);
return ret;
}
struct bsg_device *scsi_bsg_register_queue(struct scsi_device *sdev)
{
return bsg_register_queue(sdev->request_queue, &sdev->sdev_gendev,
dev_name(&sdev->sdev_gendev), scsi_bsg_sg_io_fn);
}