* [Qemu-devel] [PATCH RFC 1/3] tap: generalize code for different vnet header len
2010-07-16 9:04 [Qemu-devel] [PATCH RFC 0/3] qemu/vhost-net: mergeable buffers support Michael S. Tsirkin
@ 2010-07-16 9:04 ` Michael S. Tsirkin
2010-07-16 9:04 ` [Qemu-devel] [PATCH RFC 2/3] tap: add APIs for vnet header length Michael S. Tsirkin
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Michael S. Tsirkin @ 2010-07-16 9:04 UTC (permalink / raw)
To: kvm, qemu-devel, dlstevens
Make host vnet header length a structure field in
preparation for using this support in linux kernel.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
net/tap-linux.h | 6 ++++++
net/tap.c | 28 ++++++++++++++--------------
2 files changed, 20 insertions(+), 14 deletions(-)
diff --git a/net/tap-linux.h b/net/tap-linux.h
index 9f94358..727fcf5 100644
--- a/net/tap-linux.h
+++ b/net/tap-linux.h
@@ -52,4 +52,10 @@ struct virtio_net_hdr
uint16_t csum_offset;
};
+struct virtio_net_hdr_mrg_rxbuf
+{
+ struct virtio_net_hdr hdr;
+ uint16_t num_buffers; /* Number of merged rx buffers */
+};
+
#endif /* QEMU_TAP_H */
diff --git a/net/tap.c b/net/tap.c
index 0147dab..2866ff4 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -57,10 +57,10 @@ typedef struct TAPState {
uint8_t buf[TAP_BUFSIZE];
unsigned int read_poll : 1;
unsigned int write_poll : 1;
- unsigned int has_vnet_hdr : 1;
unsigned int using_vnet_hdr : 1;
unsigned int has_ufo: 1;
VHostNetState *vhost_net;
+ unsigned host_vnet_hdr_len;
} TAPState;
static int launch_script(const char *setup_script, const char *ifname, int fd);
@@ -121,11 +121,11 @@ static ssize_t tap_receive_iov(VLANClientState *nc, const struct iovec *iov,
TAPState *s = DO_UPCAST(TAPState, nc, nc);
const struct iovec *iovp = iov;
struct iovec iov_copy[iovcnt + 1];
- struct virtio_net_hdr hdr = { 0, };
+ struct virtio_net_hdr_mrg_rxbuf hdr = { };
- if (s->has_vnet_hdr && !s->using_vnet_hdr) {
+ if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
iov_copy[0].iov_base = &hdr;
- iov_copy[0].iov_len = sizeof(hdr);
+ iov_copy[0].iov_len = s->host_vnet_hdr_len;
memcpy(&iov_copy[1], iov, iovcnt * sizeof(*iov));
iovp = iov_copy;
iovcnt++;
@@ -139,11 +139,11 @@ static ssize_t tap_receive_raw(VLANClientState *nc, const uint8_t *buf, size_t s
TAPState *s = DO_UPCAST(TAPState, nc, nc);
struct iovec iov[2];
int iovcnt = 0;
- struct virtio_net_hdr hdr = { 0, };
+ struct virtio_net_hdr_mrg_rxbuf hdr = { };
- if (s->has_vnet_hdr) {
+ if (s->host_vnet_hdr_len) {
iov[iovcnt].iov_base = &hdr;
- iov[iovcnt].iov_len = sizeof(hdr);
+ iov[iovcnt].iov_len = s->host_vnet_hdr_len;
iovcnt++;
}
@@ -159,7 +159,7 @@ static ssize_t tap_receive(VLANClientState *nc, const uint8_t *buf, size_t size)
TAPState *s = DO_UPCAST(TAPState, nc, nc);
struct iovec iov[1];
- if (s->has_vnet_hdr && !s->using_vnet_hdr) {
+ if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
return tap_receive_raw(nc, buf, size);
}
@@ -202,9 +202,9 @@ static void tap_send(void *opaque)
break;
}
- if (s->has_vnet_hdr && !s->using_vnet_hdr) {
- buf += sizeof(struct virtio_net_hdr);
- size -= sizeof(struct virtio_net_hdr);
+ if (s->host_vnet_hdr_len && !s->using_vnet_hdr) {
+ buf += s->host_vnet_hdr_len;
+ size -= s->host_vnet_hdr_len;
}
size = qemu_send_packet_async(&s->nc, buf, size, tap_send_completed);
@@ -229,7 +229,7 @@ int tap_has_vnet_hdr(VLANClientState *nc)
assert(nc->info->type == NET_CLIENT_TYPE_TAP);
- return s->has_vnet_hdr;
+ return !!s->host_vnet_hdr_len;
}
void tap_using_vnet_hdr(VLANClientState *nc, int using_vnet_hdr)
@@ -239,7 +239,7 @@ void tap_using_vnet_hdr(VLANClientState *nc, int using_vnet_hdr)
using_vnet_hdr = using_vnet_hdr != 0;
assert(nc->info->type == NET_CLIENT_TYPE_TAP);
- assert(s->has_vnet_hdr == using_vnet_hdr);
+ assert(!!s->host_vnet_hdr_len == using_vnet_hdr);
s->using_vnet_hdr = using_vnet_hdr;
}
@@ -310,7 +310,7 @@ static TAPState *net_tap_fd_init(VLANState *vlan,
s = DO_UPCAST(TAPState, nc, nc);
s->fd = fd;
- s->has_vnet_hdr = vnet_hdr != 0;
+ s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0;
s->using_vnet_hdr = 0;
s->has_ufo = tap_probe_has_ufo(s->fd);
tap_set_offload(&s->nc, 0, 0, 0, 0, 0);
--
1.7.2.rc0.14.g41c1c
^ permalink raw reply related [flat|nested] 5+ messages in thread* [Qemu-devel] [PATCH RFC 2/3] tap: add APIs for vnet header length
2010-07-16 9:04 [Qemu-devel] [PATCH RFC 0/3] qemu/vhost-net: mergeable buffers support Michael S. Tsirkin
2010-07-16 9:04 ` [Qemu-devel] [PATCH RFC 1/3] tap: generalize code for different vnet header len Michael S. Tsirkin
@ 2010-07-16 9:04 ` Michael S. Tsirkin
2010-07-16 9:04 ` [Qemu-devel] [PATCH RFC 3/3] vhost_net: mergeable buffers support Michael S. Tsirkin
2010-07-16 9:19 ` [Qemu-devel] Re: [PATCH RFC 0/3] qemu/vhost-net: " Michael S. Tsirkin
3 siblings, 0 replies; 5+ messages in thread
From: Michael S. Tsirkin @ 2010-07-16 9:04 UTC (permalink / raw)
To: kvm, qemu-devel, dlstevens
Add APIs to control host header length. First user
will be vhost-net.
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
net/tap-aix.c | 9 +++++++++
net/tap-bsd.c | 9 +++++++++
net/tap-linux.c | 29 +++++++++++++++++++++++++++++
net/tap-linux.h | 2 ++
net/tap-solaris.c | 9 +++++++++
net/tap-win32.c | 9 +++++++++
net/tap.c | 21 +++++++++++++++++++++
net/tap.h | 4 ++++
8 files changed, 92 insertions(+), 0 deletions(-)
diff --git a/net/tap-aix.c b/net/tap-aix.c
index 4bc9f2f..e19aaba 100644
--- a/net/tap-aix.c
+++ b/net/tap-aix.c
@@ -46,6 +46,15 @@ int tap_probe_has_ufo(int fd)
return 0;
}
+int tap_probe_vnet_hdr_len(int fd, int len)
+{
+ return 0;
+}
+
+void tap_fd_set_vnet_hdr_len(int fd, int len)
+{
+}
+
void tap_fd_set_offload(int fd, int csum, int tso4,
int tso6, int ecn, int ufo)
{
diff --git a/net/tap-bsd.c b/net/tap-bsd.c
index 3773d5d..3513075 100644
--- a/net/tap-bsd.c
+++ b/net/tap-bsd.c
@@ -116,6 +116,15 @@ int tap_probe_has_ufo(int fd)
return 0;
}
+int tap_probe_vnet_hdr_len(int fd, int len)
+{
+ return 0;
+}
+
+void tap_fd_set_vnet_hdr_len(int fd, int len)
+{
+}
+
void tap_fd_set_offload(int fd, int csum, int tso4,
int tso6, int ecn, int ufo)
{
diff --git a/net/tap-linux.c b/net/tap-linux.c
index c92983c..f7aa904 100644
--- a/net/tap-linux.c
+++ b/net/tap-linux.c
@@ -129,6 +129,35 @@ int tap_probe_has_ufo(int fd)
return 1;
}
+/* Verify that we can assign given length */
+int tap_probe_vnet_hdr_len(int fd, int len)
+{
+ int orig;
+ if (ioctl(fd, TUNGETVNETHDRSZ, &orig) == -1) {
+ return 0;
+ }
+ if (ioctl(fd, TUNSETVNETHDRSZ, &len) == -1) {
+ return 0;
+ }
+ /* Restore original length: we can't handle failure. */
+ if (ioctl(fd, TUNSETVNETHDRSZ, &orig) == -1) {
+ fprintf(stderr, "TUNGETVNETHDRSZ ioctl() failed: %s. Exiting.\n",
+ strerror(errno));
+ assert(0);
+ return -errno;
+ }
+ return 1;
+}
+
+void tap_fd_set_vnet_hdr_len(int fd, int len)
+{
+ if (ioctl(fd, TUNSETVNETHDRSZ, &len) == -1) {
+ fprintf(stderr, "TUNSETVNETHDRSZ ioctl() failed: %s. Exiting.\n",
+ strerror(errno));
+ assert(0);
+ }
+}
+
void tap_fd_set_offload(int fd, int csum, int tso4,
int tso6, int ecn, int ufo)
{
diff --git a/net/tap-linux.h b/net/tap-linux.h
index 727fcf5..659e981 100644
--- a/net/tap-linux.h
+++ b/net/tap-linux.h
@@ -27,6 +27,8 @@
#define TUNSETOFFLOAD _IOW('T', 208, unsigned int)
#define TUNGETIFF _IOR('T', 210, unsigned int)
#define TUNSETSNDBUF _IOW('T', 212, int)
+#define TUNGETVNETHDRSZ _IOR('T', 215, int)
+#define TUNSETVNETHDRSZ _IOW('T', 216, int)
#endif
diff --git a/net/tap-solaris.c b/net/tap-solaris.c
index 50d127a..ca1d496 100644
--- a/net/tap-solaris.c
+++ b/net/tap-solaris.c
@@ -211,6 +211,15 @@ int tap_probe_has_ufo(int fd)
return 0;
}
+int tap_probe_vnet_hdr_len(int fd, int len)
+{
+ return 0;
+}
+
+void tap_fd_set_vnet_hdr_len(int fd, int len)
+{
+}
+
void tap_fd_set_offload(int fd, int csum, int tso4,
int tso6, int ecn, int ufo)
{
diff --git a/net/tap-win32.c b/net/tap-win32.c
index 74348da..9fe4fcd 100644
--- a/net/tap-win32.c
+++ b/net/tap-win32.c
@@ -728,6 +728,15 @@ int tap_has_vnet_hdr(VLANClientState *vc)
return 0;
}
+int tap_probe_vnet_hdr_len(int fd, int len)
+{
+ return 0;
+}
+
+void tap_fd_set_vnet_hdr_len(int fd, int len)
+{
+}
+
void tap_using_vnet_hdr(VLANClientState *vc, int using_vnet_hdr)
{
}
diff --git a/net/tap.c b/net/tap.c
index 2866ff4..e0f673c 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -232,6 +232,27 @@ int tap_has_vnet_hdr(VLANClientState *nc)
return !!s->host_vnet_hdr_len;
}
+int tap_has_vnet_hdr_len(VLANClientState *nc, int len)
+{
+ TAPState *s = DO_UPCAST(TAPState, nc, nc);
+
+ assert(nc->info->type == NET_CLIENT_TYPE_TAP);
+
+ return tap_probe_vnet_hdr_len(s->fd, len);
+}
+
+void tap_set_vnet_hdr_len(VLANClientState *nc, int len)
+{
+ TAPState *s = DO_UPCAST(TAPState, nc, nc);
+
+ assert(nc->info->type == NET_CLIENT_TYPE_TAP);
+ assert(len == sizeof(virtio_net_hdr_mrg) ||
+ len == sizeof(virtio_net_hdr));
+
+ tap_fd_set_vnet_hdr_len(s->fd, len);
+ s->host_vnet_hdr_len = len;
+}
+
void tap_using_vnet_hdr(VLANClientState *nc, int using_vnet_hdr)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
diff --git a/net/tap.h b/net/tap.h
index b8cec83..e44bd2b 100644
--- a/net/tap.h
+++ b/net/tap.h
@@ -40,13 +40,17 @@ ssize_t tap_read_packet(int tapfd, uint8_t *buf, int maxlen);
int tap_has_ufo(VLANClientState *vc);
int tap_has_vnet_hdr(VLANClientState *vc);
+int tap_has_vnet_hdr_len(VLANClientState *vc, int len);
void tap_using_vnet_hdr(VLANClientState *vc, int using_vnet_hdr);
void tap_set_offload(VLANClientState *vc, int csum, int tso4, int tso6, int ecn, int ufo);
+void tap_set_vnet_hdr_len(VLANClientState *vc, int len);
int tap_set_sndbuf(int fd, QemuOpts *opts);
int tap_probe_vnet_hdr(int fd);
+int tap_probe_vnet_hdr_len(int fd, int len);
int tap_probe_has_ufo(int fd);
void tap_fd_set_offload(int fd, int csum, int tso4, int tso6, int ecn, int ufo);
+void tap_fd_set_vnet_hdr_len(int fd, int len);
int tap_get_fd(VLANClientState *vc);
--
1.7.2.rc0.14.g41c1c
^ permalink raw reply related [flat|nested] 5+ messages in thread* [Qemu-devel] [PATCH RFC 3/3] vhost_net: mergeable buffers support
2010-07-16 9:04 [Qemu-devel] [PATCH RFC 0/3] qemu/vhost-net: mergeable buffers support Michael S. Tsirkin
2010-07-16 9:04 ` [Qemu-devel] [PATCH RFC 1/3] tap: generalize code for different vnet header len Michael S. Tsirkin
2010-07-16 9:04 ` [Qemu-devel] [PATCH RFC 2/3] tap: add APIs for vnet header length Michael S. Tsirkin
@ 2010-07-16 9:04 ` Michael S. Tsirkin
2010-07-16 9:19 ` [Qemu-devel] Re: [PATCH RFC 0/3] qemu/vhost-net: " Michael S. Tsirkin
3 siblings, 0 replies; 5+ messages in thread
From: Michael S. Tsirkin @ 2010-07-16 9:04 UTC (permalink / raw)
To: kvm, qemu-devel, dlstevens
use the new tap APIs to set header length
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
---
hw/vhost_net.c | 23 ++++++++++++++++++++++-
1 files changed, 22 insertions(+), 1 deletions(-)
diff --git a/hw/vhost_net.c b/hw/vhost_net.c
index 606aa0c..1693090 100644
--- a/hw/vhost_net.c
+++ b/hw/vhost_net.c
@@ -51,7 +51,9 @@ unsigned vhost_net_get_features(struct vhost_net *net, unsigned features)
if (!(net->dev.features & (1 << VIRTIO_RING_F_INDIRECT_DESC))) {
features &= ~(1 << VIRTIO_RING_F_INDIRECT_DESC);
}
- features &= ~(1 << VIRTIO_NET_F_MRG_RXBUF);
+ if (!(net->dev.features & (1 << VIRTIO_NET_F_MRG_RXBUF))) {
+ features &= ~(1 << VIRTIO_NET_F_MRG_RXBUF);
+ }
return features;
}
@@ -64,6 +66,9 @@ void vhost_net_ack_features(struct vhost_net *net, unsigned features)
if (features & (1 << VIRTIO_RING_F_INDIRECT_DESC)) {
net->dev.acked_features |= (1 << VIRTIO_RING_F_INDIRECT_DESC);
}
+ if (features & (1 << VIRTIO_NET_F_MRG_RXBUF)) {
+ net->dev.acked_features |= (1 << VIRTIO_NET_F_MRG_RXBUF);
+ }
}
static int vhost_net_get_fd(VLANClientState *backend)
@@ -98,6 +103,10 @@ struct vhost_net *vhost_net_init(VLANClientState *backend, int devfd)
if (r < 0) {
goto fail;
}
+ if (!tap_has_vnet_hdr_len(backend,
+ sizeof(struct virtio_net_hdr_mrg_rxbuf))) {
+ net->dev.features &= ~(1 << VIRTIO_NET_F_MRG_RXBUF);
+ }
if (~net->dev.features & net->dev.backend_features) {
fprintf(stderr, "vhost lacks feature mask %" PRIu64 " for backend\n",
(uint64_t)(~net->dev.features & net->dev.backend_features));
@@ -118,6 +127,9 @@ int vhost_net_start(struct vhost_net *net,
{
struct vhost_vring_file file = { };
int r;
+ if (net->dev.acked_features & VIRTIO_NET_F_MRG_RXBUF) {
+ tap_set_vnet_hdr_len(net->backend, sizeof(virtio_net_hdr_mrg_rxbuf));
+ }
net->dev.nvqs = 2;
net->dev.vqs = net->vqs;
@@ -145,6 +157,9 @@ fail:
}
net->vc->info->poll(net->vc, true);
vhost_dev_stop(&net->dev, dev);
+ if (net->dev.acked_features & VIRTIO_NET_F_MRG_RXBUF) {
+ tap_set_vnet_hdr_len(net->backend, sizeof(virtio_net_hdr));
+ }
return r;
}
@@ -159,11 +174,17 @@ void vhost_net_stop(struct vhost_net *net,
}
net->vc->info->poll(net->vc, true);
vhost_dev_stop(&net->dev, dev);
+ if (net->dev.acked_features & VIRTIO_NET_F_MRG_RXBUF) {
+ tap_set_vnet_hdr_len(net->backend, sizeof(virtio_net_hdr));
+ }
}
void vhost_net_cleanup(struct vhost_net *net)
{
vhost_dev_cleanup(&net->dev);
+ if (net->dev.acked_features & VIRTIO_NET_F_MRG_RXBUF) {
+ tap_set_vnet_hdr_len(net->backend, sizeof(virtio_net_hdr));
+ }
qemu_free(net);
}
#else
--
1.7.2.rc0.14.g41c1c
^ permalink raw reply related [flat|nested] 5+ messages in thread* [Qemu-devel] Re: [PATCH RFC 0/3] qemu/vhost-net: mergeable buffers support
2010-07-16 9:04 [Qemu-devel] [PATCH RFC 0/3] qemu/vhost-net: mergeable buffers support Michael S. Tsirkin
` (2 preceding siblings ...)
2010-07-16 9:04 ` [Qemu-devel] [PATCH RFC 3/3] vhost_net: mergeable buffers support Michael S. Tsirkin
@ 2010-07-16 9:19 ` Michael S. Tsirkin
3 siblings, 0 replies; 5+ messages in thread
From: Michael S. Tsirkin @ 2010-07-16 9:19 UTC (permalink / raw)
To: kvm, qemu-devel, dlstevens
On Fri, Jul 16, 2010 at 12:04:34PM +0300, Michael S. Tsirkin wrote:
> This adds mergeable buffers support in vhost-net in qemu.
> With this patch, sending raw packets while vhost-net is active should
> work as well: important for migration. Compile-tested only for now.
> David, could you please review and maybe try this out?
> The kernel side is in vhost-net-next. I intend for it to got into
> net-next and then into 2.6.36.
>
> TODO: basic test. migration test, send pull request.
This is on top of 46c85dab1c2ffa1363c07bf7c161921ff613c0b6 in qemu-kvm.
> Michael S. Tsirkin (3):
> tap: generalize code for different vnet header len
> tap: add APIs for vnet header length
> vhost_net: mergeable buffers support
>
> hw/vhost_net.c | 23 ++++++++++++++++++++++-
> net/tap-aix.c | 9 +++++++++
> net/tap-bsd.c | 9 +++++++++
> net/tap-linux.c | 29 +++++++++++++++++++++++++++++
> net/tap-linux.h | 8 ++++++++
> net/tap-solaris.c | 9 +++++++++
> net/tap-win32.c | 9 +++++++++
> net/tap.c | 49 +++++++++++++++++++++++++++++++++++--------------
> net/tap.h | 4 ++++
> 9 files changed, 134 insertions(+), 15 deletions(-)
>
> --
> MST
>
>
^ permalink raw reply [flat|nested] 5+ messages in thread