diff options
Diffstat (limited to 'drivers/scsi/scsi_bsg.c')
-rw-r--r-- | drivers/scsi/scsi_bsg.c | 95 |
1 files changed, 95 insertions, 0 deletions
diff --git a/drivers/scsi/scsi_bsg.c b/drivers/scsi/scsi_bsg.c new file mode 100644 index 000000000000..3bdb28940460 --- /dev/null +++ b/drivers/scsi/scsi_bsg.c @@ -0,0 +1,95 @@ +// 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_check_proto(struct sg_io_v4 *hdr) +{ + if (hdr->protocol != BSG_PROTOCOL_SCSI || + hdr->subprotocol != BSG_SUB_PROTOCOL_SCSI_CMD) + return -EINVAL; + return 0; +} + +static int scsi_bsg_fill_hdr(struct request *rq, struct sg_io_v4 *hdr, + fmode_t mode) +{ + struct scsi_request *sreq = scsi_req(rq); + + if (hdr->dout_xfer_len && hdr->din_xfer_len) { + pr_warn_once("BIDI support in bsg has been removed.\n"); + return -EOPNOTSUPP; + } + + sreq->cmd_len = hdr->request_len; + if (sreq->cmd_len > BLK_MAX_CDB) { + sreq->cmd = kzalloc(sreq->cmd_len, GFP_KERNEL); + if (!sreq->cmd) + return -ENOMEM; + } + + if (copy_from_user(sreq->cmd, uptr64(hdr->request), sreq->cmd_len)) + return -EFAULT; + if (blk_verify_command(sreq->cmd, mode)) + return -EPERM; + return 0; +} + +static int scsi_bsg_complete_rq(struct request *rq, struct sg_io_v4 *hdr) +{ + struct scsi_request *sreq = scsi_req(rq); + int ret = 0; + + /* + * fill in all the output members + */ + hdr->device_status = sreq->result & 0xff; + hdr->transport_status = host_byte(sreq->result); + hdr->driver_status = 0; + if (scsi_status_is_check_condition(sreq->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 (sreq->sense_len && hdr->response) { + int len = min_t(unsigned int, hdr->max_response_len, + sreq->sense_len); + + if (copy_to_user(uptr64(hdr->response), sreq->sense, len)) + ret = -EFAULT; + else + hdr->response_len = len; + } + + if (rq_data_dir(rq) == READ) + hdr->din_resid = sreq->resid_len; + else + hdr->dout_resid = sreq->resid_len; + + return ret; +} + +static void scsi_bsg_free_rq(struct request *rq) +{ + scsi_req_free_cmd(scsi_req(rq)); +} + +static const struct bsg_ops scsi_bsg_ops = { + .check_proto = scsi_bsg_check_proto, + .fill_hdr = scsi_bsg_fill_hdr, + .complete_rq = scsi_bsg_complete_rq, + .free_rq = scsi_bsg_free_rq, +}; + +int scsi_bsg_register_queue(struct request_queue *q, struct device *parent) +{ + return bsg_register_queue(q, parent, dev_name(parent), &scsi_bsg_ops); +} |