diff options
Diffstat (limited to 'drivers/net/tun.c')
-rw-r--r-- | drivers/net/tun.c | 36 |
1 files changed, 25 insertions, 11 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 807815fc9968..7c8343a4f918 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -981,6 +981,7 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, struct sk_buff *skb; size_t len = total_len, align = NET_SKB_PAD, linear; struct virtio_net_hdr gso = { 0 }; + int good_linear; int offset = 0; int copylen; bool zerocopy = false; @@ -1021,12 +1022,16 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, return -EINVAL; } + good_linear = SKB_MAX_HEAD(align); + if (msg_control) { /* There are 256 bytes to be copied in skb, so there is * enough room for skb expand head in case it is used. * The rest of the buffer is mapped from userspace. */ copylen = gso.hdr_len ? gso.hdr_len : GOODCOPY_LEN; + if (copylen > good_linear) + copylen = good_linear; linear = copylen; if (iov_pages(iv, offset + copylen, count) <= MAX_SKB_FRAGS) zerocopy = true; @@ -1034,7 +1039,10 @@ static ssize_t tun_get_user(struct tun_struct *tun, struct tun_file *tfile, if (!zerocopy) { copylen = len; - linear = gso.hdr_len; + if (gso.hdr_len > good_linear) + linear = good_linear; + else + linear = gso.hdr_len; } skb = tun_alloc_skb(tfile, align, copylen, linear, noblock); @@ -1176,7 +1184,7 @@ static ssize_t tun_put_user(struct tun_struct *tun, { struct tun_pi pi = { 0, skb->protocol }; ssize_t total = 0; - int vlan_offset = 0; + int vlan_offset = 0, copied; if (!(tun->flags & TUN_NO_PI)) { if ((len -= sizeof(pi)) < 0) @@ -1240,6 +1248,8 @@ static ssize_t tun_put_user(struct tun_struct *tun, total += tun->vnet_hdr_sz; } + copied = total; + total += skb->len; if (!vlan_tx_tag_present(skb)) { len = min_t(int, skb->len, len); } else { @@ -1254,24 +1264,24 @@ static ssize_t tun_put_user(struct tun_struct *tun, vlan_offset = offsetof(struct vlan_ethhdr, h_vlan_proto); len = min_t(int, skb->len + VLAN_HLEN, len); + total += VLAN_HLEN; copy = min_t(int, vlan_offset, len); - ret = skb_copy_datagram_const_iovec(skb, 0, iv, total, copy); + ret = skb_copy_datagram_const_iovec(skb, 0, iv, copied, copy); len -= copy; - total += copy; + copied += copy; if (ret || !len) goto done; copy = min_t(int, sizeof(veth), len); - ret = memcpy_toiovecend(iv, (void *)&veth, total, copy); + ret = memcpy_toiovecend(iv, (void *)&veth, copied, copy); len -= copy; - total += copy; + copied += copy; if (ret || !len) goto done; } - skb_copy_datagram_const_iovec(skb, vlan_offset, iv, total, len); - total += len; + skb_copy_datagram_const_iovec(skb, vlan_offset, iv, copied, len); done: tun->dev->stats.tx_packets++; @@ -1293,7 +1303,8 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, if (unlikely(!noblock)) add_wait_queue(&tfile->wq.wait, &wait); while (len) { - current->state = TASK_INTERRUPTIBLE; + if (unlikely(!noblock)) + current->state = TASK_INTERRUPTIBLE; /* Read frames from the queue */ if (!(skb = skb_dequeue(&tfile->socket.sk->sk_receive_queue))) { @@ -1320,9 +1331,10 @@ static ssize_t tun_do_read(struct tun_struct *tun, struct tun_file *tfile, break; } - current->state = TASK_RUNNING; - if (unlikely(!noblock)) + if (unlikely(!noblock)) { + current->state = TASK_RUNNING; remove_wait_queue(&tfile->wq.wait, &wait); + } return ret; } @@ -1346,6 +1358,8 @@ static ssize_t tun_chr_aio_read(struct kiocb *iocb, const struct iovec *iv, ret = tun_do_read(tun, tfile, iocb, iv, len, file->f_flags & O_NONBLOCK); ret = min_t(ssize_t, ret, len); + if (ret > 0) + iocb->ki_pos = ret; out: tun_put(tun); return ret; |