scsi: bsg: Move the whole request execution into the SCSI/transport handlers
Remove the amount of indirect calls by making the handler responsible for
the entire execution of the request.
Link: https://lore.kernel.org/r/20210729064845.1044147-5-hch@lst.de
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
diff --git a/drivers/scsi/scsi_bsg.c b/drivers/scsi/scsi_bsg.c
index c0d41c4..d13a67b 100644
--- a/drivers/scsi/scsi_bsg.c
+++ b/drivers/scsi/scsi_bsg.c
@@ -9,42 +9,57 @@
#define uptr64(val) ((void __user *)(uintptr_t)(val))
-static int scsi_bsg_check_proto(struct sg_io_v4 *hdr)
+static int scsi_bsg_sg_io_fn(struct request_queue *q, struct sg_io_v4 *hdr,
+ fmode_t mode, unsigned int timeout)
{
+ struct scsi_request *sreq;
+ struct request *rq;
+ struct bio *bio;
+ int ret;
+
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;
}
+ rq = blk_get_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;
+
+ ret = -ENOMEM;
+ sreq = scsi_req(rq);
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;
+ goto out_put_request;
}
+ ret = -EFAULT;
if (copy_from_user(sreq->cmd, uptr64(hdr->request), sreq->cmd_len))
- return -EFAULT;
+ goto out_free_cmd;
+ ret = -EPERM;
if (!scsi_cmd_allowed(sreq->cmd, mode))
- return -EPERM;
- return 0;
-}
+ goto out_free_cmd;
-static int scsi_bsg_complete_rq(struct request *rq, struct sg_io_v4 *hdr)
-{
- struct scsi_request *sreq = scsi_req(rq);
- int 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_free_cmd;
+
+ bio = rq->bio;
+ blk_execute_rq(NULL, rq, !(hdr->flags & BSG_FLAG_Q_AT_TAIL));
/*
* fill in all the output members
@@ -74,23 +89,17 @@ static int scsi_bsg_complete_rq(struct request *rq, struct sg_io_v4 *hdr)
else
hdr->dout_resid = sreq->resid_len;
+ blk_rq_unmap_user(bio);
+
+out_free_cmd:
+ scsi_req_free_cmd(scsi_req(rq));
+out_put_request:
+ blk_put_request(rq);
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,
-};
-
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_ops);
+ dev_name(&sdev->sdev_gendev), scsi_bsg_sg_io_fn);
}