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authorJulian Wiedmann <jwi@linux.vnet.ibm.com>2017-01-10 17:10:34 +0100
committerDavid S. Miller <davem@davemloft.net>2017-01-10 21:08:29 -0500
commitdc5367bcc556e97555fc94a32cd1aadbebdff47e (patch)
tree78778f65fe742ff199468fc3ac00e572513b89bc /net/iucv/af_iucv.c
parentnet: add the AF_QIPCRTR entries to family name tables (diff)
downloadlinux-dev-dc5367bcc556e97555fc94a32cd1aadbebdff47e.tar.xz
linux-dev-dc5367bcc556e97555fc94a32cd1aadbebdff47e.zip
net/af_iucv: don't use paged skbs for TX on HiperSockets
With commit e53743994e21 ("af_iucv: use paged SKBs for big outbound messages"), we transmit paged skbs for both of AF_IUCV's transport modes (IUCV or HiperSockets). The qeth driver for Layer 3 HiperSockets currently doesn't support NETIF_F_SG, so these skbs would just be linearized again by the stack. Avoid that overhead by using paged skbs only for IUCV transport. cc stable, since this also circumvents a significant skb leak when sending large messages (where the skb then needs to be linearized). Signed-off-by: Julian Wiedmann <jwi@linux.vnet.ibm.com> Signed-off-by: Ursula Braun <ubraun@linux.vnet.ibm.com> Cc: <stable@vger.kernel.org> # v4.8+ Fixes: e53743994e21 ("af_iucv: use paged SKBs for big outbound messages") Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'net/iucv/af_iucv.c')
-rw-r--r--net/iucv/af_iucv.c25
1 files changed, 14 insertions, 11 deletions
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index cfb9e5f4e28f..13190b38f22e 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -1044,7 +1044,8 @@ static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
{
struct sock *sk = sock->sk;
struct iucv_sock *iucv = iucv_sk(sk);
- size_t headroom, linear;
+ size_t headroom = 0;
+ size_t linear;
struct sk_buff *skb;
struct iucv_message txmsg = {0};
struct cmsghdr *cmsg;
@@ -1122,18 +1123,20 @@ static int iucv_sock_sendmsg(struct socket *sock, struct msghdr *msg,
* this is fine for SOCK_SEQPACKET (unless we want to support
* segmented records using the MSG_EOR flag), but
* for SOCK_STREAM we might want to improve it in future */
- headroom = (iucv->transport == AF_IUCV_TRANS_HIPER)
- ? sizeof(struct af_iucv_trans_hdr) + ETH_HLEN : 0;
- if (headroom + len < PAGE_SIZE) {
+ if (iucv->transport == AF_IUCV_TRANS_HIPER) {
+ headroom = sizeof(struct af_iucv_trans_hdr) + ETH_HLEN;
linear = len;
} else {
- /* In nonlinear "classic" iucv skb,
- * reserve space for iucv_array
- */
- if (iucv->transport != AF_IUCV_TRANS_HIPER)
- headroom += sizeof(struct iucv_array) *
- (MAX_SKB_FRAGS + 1);
- linear = PAGE_SIZE - headroom;
+ if (len < PAGE_SIZE) {
+ linear = len;
+ } else {
+ /* In nonlinear "classic" iucv skb,
+ * reserve space for iucv_array
+ */
+ headroom = sizeof(struct iucv_array) *
+ (MAX_SKB_FRAGS + 1);
+ linear = PAGE_SIZE - headroom;
+ }
}
skb = sock_alloc_send_pskb(sk, headroom + linear, len - linear,
noblock, &err, 0);