mm: gup: use get_user_pages_unlocked

This allows those get_user_pages calls to pass FAULT_FLAG_ALLOW_RETRY to
the page fault in order to release the mmap_sem during the I/O.

Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Andres Lagar-Cavilla <andreslc@google.com>
Cc: Peter Feiner <pfeiner@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 2 insertions, 4 deletions

diff --git a/drivers/media/pci/ivtv/ivtv-udma.c b/drivers/media/pci/ivtv/ivtv-udma.c
index bee2329e0b2e..24152accc66c 100644
--- a/drivers/media/pci/ivtv/ivtv-udma.c
+++ b/drivers/media/pci/ivtv/ivtv-udma.c
@@ -124,10 +124,8 @@ int ivtv_udma_setup(struct ivtv *itv, unsigned long ivtv_dest_addr,
         }
 
         /* Get user pages for DMA Xfer */
-        down_read(&current->mm->mmap_sem);
-        err = get_user_pages(current, current->mm,
-                        user_dma.uaddr, user_dma.page_count, 0, 1, dma->map, NULL);
-        up_read(&current->mm->mmap_sem);
+        err = get_user_pages_unlocked(current, current->mm,
+                        user_dma.uaddr, user_dma.page_count, 0, 1, dma->map);
 
         if (user_dma.page_count != err) {
                 IVTV_DEBUG_WARN("failed to map user pages, returned %d instead of %d\n",