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/net/ceph/pagevec.c b/net/ceph/pagevec.c
index 555013034f7a..096d91447e06 100644
--- a/net/ceph/pagevec.c
+++ b/net/ceph/pagevec.c
@@ -23,17 +23,15 @@ struct page **ceph_get_direct_page_vector(const void __user *data,
         if (!pages)
                 return ERR_PTR(-ENOMEM);
 
-        down_read(&current->mm->mmap_sem);
         while (got < num_pages) {
-                rc = get_user_pages(current, current->mm,
+                rc = get_user_pages_unlocked(current, current->mm,
                     (unsigned long)data + ((unsigned long)got * PAGE_SIZE),
-                    num_pages - got, write_page, 0, pages + got, NULL);
+                    num_pages - got, write_page, 0, pages + got);
                 if (rc < 0)
                         break;
                 BUG_ON(rc == 0);
                 got += rc;
         }
-        up_read(&current->mm->mmap_sem);
         if (rc < 0)
                 goto fail;
         return pages;