From cbbd26b8b1a6af9c02e2b6523e12bd50cc765059 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 1 Nov 2016 22:09:04 -0400 Subject: [iov_iter] new primitives - copy_from_iter_full() and friends copy_from_iter_full(), copy_from_iter_full_nocache() and csum_and_copy_from_iter_full() - counterparts of copy_from_iter() et.al., advancing iterator only in case of successful full copy and returning whether it had been successful or not. Convert some obvious users. *NOTE* - do not blindly assume that something is a good candidate for those unless you are sure that not advancing iov_iter in failure case is the right thing in this case. Anything that does short read/short write kind of stuff (or is in a loop, etc.) is unlikely to be a good one. Signed-off-by: Al Viro --- drivers/net/macvtap.c | 4 +--- 1 file changed, 1 insertion(+), 3 deletions(-) (limited to 'drivers/net/macvtap.c') diff --git a/drivers/net/macvtap.c b/drivers/net/macvtap.c index 070e3290aa6e..19d81ca3fb49 100644 --- a/drivers/net/macvtap.c +++ b/drivers/net/macvtap.c @@ -673,7 +673,6 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, int depth; bool zerocopy = false; size_t linear; - ssize_t n; if (q->flags & IFF_VNET_HDR) { vnet_hdr_len = q->vnet_hdr_sz; @@ -684,8 +683,7 @@ static ssize_t macvtap_get_user(struct macvtap_queue *q, struct msghdr *m, len -= vnet_hdr_len; err = -EFAULT; - n = copy_from_iter(&vnet_hdr, sizeof(vnet_hdr), from); - if (n != sizeof(vnet_hdr)) + if (!copy_from_iter_full(&vnet_hdr, sizeof(vnet_hdr), from)) goto err; iov_iter_advance(from, vnet_hdr_len - sizeof(vnet_hdr)); if ((vnet_hdr.flags & VIRTIO_NET_HDR_F_NEEDS_CSUM) && -- cgit v1.2.3-59-g8ed1b