From e0b46d0ee9c240c7430a47e9b0365674d4a04522 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Fri, 7 Nov 2014 21:22:23 +0800 Subject: [PATCH] tun: Use iovec iterators This patch removes the use of skb_copy_datagram_const_iovec in favour of the iovec iterator-based skb_copy_datagram_iter. Signed-off-by: Herbert Xu Signed-off-by: David S. Miller --- drivers/net/tun.c | 65 ++++++++++++++++++++++------------------------- 1 file changed, 30 insertions(+), 35 deletions(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 9dd3746994a4..2ff769bf3f35 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -71,6 +71,7 @@ #include #include #include +#include #include @@ -1230,11 +1231,11 @@ static ssize_t tun_chr_aio_write(struct kiocb *iocb, const struct iovec *iv, static ssize_t tun_put_user(struct tun_struct *tun, struct tun_file *tfile, struct sk_buff *skb, - const struct iovec *iv, int len) + struct iov_iter *iter) { struct tun_pi pi = { 0, skb->protocol }; - ssize_t total = 0; - int vlan_offset = 0, copied; + ssize_t total; + int vlan_offset; int vlan_hlen = 0; int vnet_hdr_sz = 0; @@ -1244,23 +1245,25 @@ static ssize_t tun_put_user(struct tun_struct *tun, if (tun->flags & TUN_VNET_HDR) vnet_hdr_sz = tun->vnet_hdr_sz; + total = skb->len + vlan_hlen + vnet_hdr_sz; + if (!(tun->flags & TUN_NO_PI)) { - if ((len -= sizeof(pi)) < 0) + if (iov_iter_count(iter) < sizeof(pi)) return -EINVAL; - if (len < skb->len + vlan_hlen + vnet_hdr_sz) { + total += sizeof(pi); + if (iov_iter_count(iter) < total) { /* Packet will be striped */ pi.flags |= TUN_PKT_STRIP; } - if (memcpy_toiovecend(iv, (void *) &pi, 0, sizeof(pi))) + if (copy_to_iter(&pi, sizeof(pi), iter) != sizeof(pi)) return -EFAULT; - total += sizeof(pi); } if (vnet_hdr_sz) { struct virtio_net_hdr gso = { 0 }; /* no info leak */ - if ((len -= vnet_hdr_sz) < 0) + if (iov_iter_count(iter) < vnet_hdr_sz) return -EINVAL; if (skb_is_gso(skb)) { @@ -1299,17 +1302,12 @@ static ssize_t tun_put_user(struct tun_struct *tun, gso.flags = VIRTIO_NET_HDR_F_DATA_VALID; } /* else everything is zero */ - if (unlikely(memcpy_toiovecend(iv, (void *)&gso, total, - sizeof(gso)))) + if (copy_to_iter(&gso, sizeof(gso), iter) != sizeof(gso)) return -EFAULT; - total += vnet_hdr_sz; } - copied = total; - len = min_t(int, skb->len + vlan_hlen, len); - total += skb->len + vlan_hlen; if (vlan_hlen) { - int copy, ret; + int ret; struct { __be16 h_vlan_proto; __be16 h_vlan_TCI; @@ -1320,36 +1318,32 @@ static ssize_t tun_put_user(struct tun_struct *tun, vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); - copy = min_t(int, vlan_offset, len); - ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy); - len -= copy; - copied += copy; - if (ret || !len) + ret = skb_copy_datagram_iter(skb, 0, iter, vlan_offset); + if (ret || !iov_iter_count(iter)) goto done; - copy = min_t(int, sizeof(veth), len); - ret = memcpy_toiovecend(iv, (void *)&veth, copied, copy); - len -= copy; - copied += copy; - if (ret || !len) + ret = copy_to_iter(&veth, sizeof(veth), iter); + if (ret != sizeof(veth) || !iov_iter_count(iter)) goto done; } - skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len); + skb_copy_datagram_iter(skb, vlan_offset, iter, skb->len - vlan_offset); done: tun->dev->stats.tx_packets++; - tun->dev->stats.tx_bytes += len; + tun->dev->stats.tx_bytes += skb->len + vlan_hlen; return total; } static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, - const struct iovec *iv, ssize_t len, int noblock) + const struct iovec *iv, unsigned long segs, + ssize_t len, int noblock) { struct sk_buff *skb; ssize_t ret = 0; int peeked, err, off = 0; + struct iov_iter iter; tun_debug(KERN_INFO, tun, "tun_do_read\n"); @@ -1362,11 +1356,12 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, /* Read frames from queue */ skb = __skb_recv_datagram(tfile->socket.sk, noblock ? MSG_DONTWAIT : 0, &peeked, &off, &err); - if (skb) { - ret = tun_put_user(tun, tfile, skb, iv, len); - kfree_skb(skb); - } else - ret = err; + if (!skb) + return ret; + + iov_iter_init(&iter, READ, iv, segs, len); + ret = tun_put_user(tun, tfile, skb, &iter); + kfree_skb(skb); return ret; } @@ -1387,7 +1382,7 @@ static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv, goto out; } - ret = tun_do_read(tun, tfile, iv, len, + ret = tun_do_read(tun, tfile, iv, count, len, file->f_flags & O_NONBLOCK); ret = min_t(ssize_t, ret, len); if (ret > 0) @@ -1488,7 +1483,7 @@ static int tun_recvmsg(struct kiocb *iocb, struct socket *sock, SOL_PACKET, TUN_TX_TIMESTAMP); goto out; } - ret = tun_do_read(tun, tfile, m->msg_iov, total_len, + ret = tun_do_read(tun, tfile, m->msg_iov, m->msg_iovlen, total_len, flags & MSG_DONTWAIT); if (ret > total_len) { m->msg_flags |= MSG_TRUNC; -- 2.20.1