tcm_vhost: Use iov_num_pages to calculate sgl_count

Signed-off-by: Asias He <asias@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

diff --git a/drivers/vhost/tcm_vhost.c b/drivers/vhost/tcm_vhost.c
index defc28595656897165ee97fa84b2cf96fa6b64cb..62058d7a562f67b87fe0fe6e5e5c77415a22b1f7 100644 (file)
--- a/drivers/vhost/tcm_vhost.c
+++ b/drivers/vhost/tcm_vhost.c
@@ -479,11 +479,9 @@ static int vhost_scsi_map_iov_to_sgl(struct tcm_vhost_cmd *tv_cmd,
         * Find out how long sglist needs to be
         */
        sgl_count = 0;
-       for (i = 0; i < niov; i++) {
-               sgl_count += (((uintptr_t)iov[i].iov_base + iov[i].iov_len +
-                               PAGE_SIZE - 1) >> PAGE_SHIFT) -
-                               ((uintptr_t)iov[i].iov_base >> PAGE_SHIFT);
-       }
+       for (i = 0; i < niov; i++)
+               sgl_count += iov_num_pages(&iov[i]);
+
        /* TODO overflow checking */
 
        sg = kmalloc(sizeof(tv_cmd->tvc_sgl[0]) * sgl_count, GFP_ATOMIC);