From 4038acdb187e226e72df393ae3dd150df857e8a3 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 3 Oct 2016 20:38:55 -0400 Subject: [PATCH] consistent treatment of EFAULT on O_DIRECT read/write Make local filesystems treat a fault as shortened IO, returning -EFAULT only if nothing had been transferred. That's how everything else (NFS, FUSE, ceph, Lustre) behaves. Signed-off-by: Al Viro --- fs/direct-io.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/fs/direct-io.c b/fs/direct-io.c index 7c3ce73cb617..fb9aa16a7727 100644 --- a/fs/direct-io.c +++ b/fs/direct-io.c @@ -246,6 +246,9 @@ static ssize_t dio_complete(struct dio *dio, ssize_t ret, bool is_async) if ((dio->op == REQ_OP_READ) && ((offset + transferred) > dio->i_size)) transferred = dio->i_size - offset; + /* ignore EFAULT if some IO has been done */ + if (unlikely(ret == -EFAULT) && transferred) + ret = 0; } if (ret == 0) -- 2.20.1