xsk: fix 64-bit division

i386 builds report:
  net/xdp/xdp_umem.o: In function `xdp_umem_reg':
  xdp_umem.c:(.text+0x47e): undefined reference to `__udivdi3'

This fix uses div_u64 instead of the GCC built-in.

Fixes: c0c77d8fb787 ("xsk: add user memory registration support sockopt")
Signed-off-by: Björn Töpel <bjorn.topel@intel.com>
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
index 881dfde..2b47a1d 100644 (file)
--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -209,7 +209,7 @@ int xdp_umem_reg(struct xdp_umem *umem, struct xdp_umem_reg *mr)
        if ((addr + size) < addr)
                return -EINVAL;
 
-       nframes = size / frame_size;
+       nframes = (unsigned int)div_u64(size, frame_size);
        if (nframes == 0 || nframes > UINT_MAX)
                return -EINVAL;