sg: remove sg_read_xfer

sg_read_xfer was used to copy data to user space for READ
commands. blk_rq_unmap_user does the job so sg_read_xfer does nothing
useful.

Signed-off-by: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

1 files changed, 5 insertions, 28 deletions

diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index 07bd68331303..df8bf67b171a 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -188,7 +188,6 @@ static ssize_t sg_new_write(Sg_fd *sfp, struct file *file,
                         int read_only, Sg_request **o_srp);
 static int sg_common_write(Sg_fd * sfp, Sg_request * srp,
                            unsigned char *cmnd, int timeout, int blocking);
-static int sg_read_xfer(Sg_request * srp);
 static int sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer);
 static void sg_remove_scat(Sg_scatter_hold * schp);
 static void sg_build_reserve(Sg_fd * sfp, int req_size);
@@ -523,8 +522,11 @@ sg_new_read(Sg_fd * sfp, char __user *buf, size_t count, Sg_request * srp)
                 err = -EFAULT;
                 goto err_out;
         }
-        err = sg_read_xfer(srp);
-      err_out:
+        if (srp->bio) {
+                err = blk_rq_unmap_user(srp->bio);
+                srp->bio = NULL;
+        }
+err_out:
         sg_finish_rem_req(srp);
         return (0 == err) ? count : err;
 }
@@ -1832,31 +1834,6 @@ sg_remove_scat(Sg_scatter_hold * schp)
 }
 
 static int
-sg_read_xfer(Sg_request * srp)
-{
-        sg_io_hdr_t *hp = &srp->header;
-        Sg_scatter_hold *schp = &srp->data;
-        int num_xfer = 0;
-        int dxfer_dir = hp->dxfer_direction;
-        int new_interface = ('\0' == hp->interface_id) ? 0 : 1;
-
-        if ((SG_DXFER_UNKNOWN == dxfer_dir) || (SG_DXFER_FROM_DEV == dxfer_dir)
-            || (SG_DXFER_TO_FROM_DEV == dxfer_dir)) {
-                num_xfer = hp->dxfer_len;
-                if (schp->bufflen < num_xfer)
-                        num_xfer = schp->bufflen;
-        }
-        if ((num_xfer <= 0) || (schp->dio_in_use) ||
-            (new_interface
-             && ((SG_FLAG_NO_DXFER | SG_FLAG_MMAP_IO) & hp->flags)))
-                return 0;
-
-        SCSI_LOG_TIMEOUT(4, printk("sg_read_xfer: num_xfer=%d, iovec_count=%d, k_use_sg=%d\n",
-                          num_xfer, (int)hp->iovec_count, schp->k_use_sg));
-        return 0;
-}
-
-static int
 sg_read_oxfer(Sg_request * srp, char __user *outp, int num_read_xfer)
 {
         Sg_scatter_hold *schp = &srp->data;