path: root/net/xdp
diff options
authorDavidlohr Bueso <dave@stgolabs.net>2019-02-11 08:15:29 -0800
committerDaniel Borkmann <daniel@iogearbox.net>2019-02-11 20:51:09 +0100
commite451eb51068496054d071af10b3530af4002a4f4 (patch)
tree16bb1b5cf6371282e39850d1c98978f261c3cb57 /net/xdp
parentbpf: fix lockdep false positive in stackmap (diff)
xsk: share the mmap_sem for page pinning
Holding mmap_sem exclusively for a gup() is an overkill. Lets share the lock and replace the gup call for gup_longterm(), as it is better suited for the lifetime of the pinning. Fixes: c0c77d8fb787 ("xsk: add user memory registration support sockopt") Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Cc: David S. Miller <davem@davemloft.net> Cc: Bjorn Topel <bjorn.topel@intel.com> Cc: Magnus Karlsson <magnus.karlsson@intel.com> CC: netdev@vger.kernel.org Acked-by: Björn Töpel <bjorn.topel@intel.com> Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'net/xdp')
1 files changed, 4 insertions, 4 deletions
diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c
index d4de871e7d4d..597866e7c441 100644
--- a/net/xdp/xdp_umem.c
+++ b/net/xdp/xdp_umem.c
@@ -259,10 +259,10 @@ static int xdp_umem_pin_pages(struct xdp_umem *umem)
if (!umem->pgs)
return -ENOMEM;
- down_write(&current->mm->mmap_sem);
- npgs = get_user_pages(umem->address, umem->npgs,
- gup_flags, &umem->pgs[0], NULL);
- up_write(&current->mm->mmap_sem);
+ down_read(&current->mm->mmap_sem);
+ npgs = get_user_pages_longterm(umem->address, umem->npgs,
+ gup_flags, &umem->pgs[0], NULL);
+ up_read(&current->mm->mmap_sem);
if (npgs != umem->npgs) {
if (npgs >= 0) {