d/freebsd-dev
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

hyperv/vmbus: Avoid extra header copy.

Browse Source 
MFC after:	1 week
Sponsored by:	Microsoft
Differential Revision:	https://reviews.freebsd.org/D8395
This commit is contained in:
Sepherosa Ziehau 2016-11-01 08:30:06 +00:00
parent 8966e5d5b3
commit a457fab84c
Notes: svn2git 2020-12-20 02:59:44 +00:00 
svn path=/head/; revision=308168
1 changed files with 15 additions and 11 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

26
sys/dev/hyperv/vmbus/vmbus_chan.c
View File

@ -926,28 +926,28 @@ vmbus_chan_recv(struct vmbus_channel *chan, void *data, int *dlen0,
int
vmbus_chan_recv_pkt(struct vmbus_channel *chan,
struct vmbus_chanpkt_hdr *pkt0, int *pktlen0)
struct vmbus_chanpkt_hdr *pkt, int *pktlen0)
{
struct vmbus_chanpkt_hdr pkt;
int error, pktlen;
int error, pktlen, pkt_hlen;
error = vmbus_rxbr_peek(&chan->ch_rxbr, &pkt, sizeof(pkt));
pkt_hlen = sizeof(*pkt);
error = vmbus_rxbr_peek(&chan->ch_rxbr, pkt, pkt_hlen);
if (error)
return (error);
if (__predict_false(pkt.cph_hlen < VMBUS_CHANPKT_HLEN_MIN)) {
vmbus_chan_printf(chan, "invalid hlen %u\n", pkt.cph_hlen);
if (__predict_false(pkt->cph_hlen < VMBUS_CHANPKT_HLEN_MIN)) {
vmbus_chan_printf(chan, "invalid hlen %u\n", pkt->cph_hlen);
/* XXX this channel is dead actually. */
return (EIO);
}
if (__predict_false(pkt.cph_hlen > pkt.cph_tlen)) {
if (__predict_false(pkt->cph_hlen > pkt->cph_tlen)) {
vmbus_chan_printf(chan, "invalid hlen %u and tlen %u\n",
pkt.cph_hlen, pkt.cph_tlen);
pkt->cph_hlen, pkt->cph_tlen);
/* XXX this channel is dead actually. */
return (EIO);
}
pktlen = VMBUS_CHANPKT_GETLEN(pkt.cph_tlen);
pktlen = VMBUS_CHANPKT_GETLEN(pkt->cph_tlen);
if (*pktlen0 < pktlen) {
/* Return the size of this packet. */
*pktlen0 = pktlen;
@ -955,8 +955,12 @@ vmbus_chan_recv_pkt(struct vmbus_channel *chan,
}
*pktlen0 = pktlen;
/* Include packet header */
error = vmbus_rxbr_read(&chan->ch_rxbr, pkt0, pktlen, 0);
/*
* Skip the fixed-size packet header, which has been filled
* by the above vmbus_rxbr_peek().
*/
error = vmbus_rxbr_read(&chan->ch_rxbr, pkt + 1,
pktlen - pkt_hlen, pkt_hlen);
KASSERT(!error, ("vmbus_rxbr_read failed"));
return (0);