[PATCH] rapidio: use get_user_pages_unlocked()

[Lorenzo Stoakes]

Moving from get_user_pages() to get_user_pages_unlocked() simplifies the code
and takes advantage of VM_FAULT_RETRY functionality when faulting in pages.

Signed-off-by: Lorenzo Stoakes <lstoa...@gmail.com>
---
 drivers/rapidio/devices/rio_mport_cdev.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/drivers/rapidio/devices/rio_mport_cdev.c 
b/drivers/rapidio/devices/rio_mport_cdev.c
index 9013a58..5fdd081 100644
--- a/drivers/rapidio/devices/rio_mport_cdev.c
+++ b/drivers/rapidio/devices/rio_mport_cdev.c
@@ -889,13 +889,11 @@ rio_dma_transfer(struct file *filp, u32 transfer_mode,
                        goto err_req;
                }
 
-               down_read(&current->mm->mmap_sem);
-               pinned = get_user_pages(
+               pinned = get_user_pages_unlocked(
                                (unsigned long)xfer->loc_addr & PAGE_MASK,
                                nr_pages,
-                               dir == DMA_FROM_DEVICE ? FOLL_WRITE : 0,
-                               page_list, NULL);
-               up_read(&current->mm->mmap_sem);
+                               page_list,
+                               dir == DMA_FROM_DEVICE ? FOLL_WRITE : 0);
 
                if (pinned != nr_pages) {
                        if (pinned < 0) {
-- 
2.10.2