From: Andrew Melnychenko <andrew@daynix.com>

Added tap uso check with stubs for non-Linux systems.

Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
---
 hw/net/virtio-net.c | 15 +++++++++++++++
 include/net/net.h   |  3 +++
 net/net.c           |  9 +++++++++
 net/tap-bsd.c       |  5 +++++
 net/tap-linux.c     | 12 ++++++++++++
 net/tap-solaris.c   |  5 +++++
 net/tap-stub.c      |  5 +++++
 net/tap.c           | 12 ++++++++++++
 net/tap_int.h       |  1 +
 9 files changed, 67 insertions(+)

diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
index e76cad923b..d950d3a77f 100644
--- a/hw/net/virtio-net.c
+++ b/hw/net/virtio-net.c
@@ -659,6 +659,15 @@ static int peer_has_ufo(VirtIONet *n)
     return n->has_ufo;
 }
 
+static int peer_has_uso(VirtIONet *n)
+{
+    if (!peer_has_vnet_hdr(n)) {
+        return 0;
+    }
+
+    return qemu_has_uso(qemu_get_queue(n->nic)->peer);
+}
+
 static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs,
                                        int version_1, int hash_report)
 {
@@ -808,6 +817,12 @@ static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features,
         virtio_clear_feature(&features, VIRTIO_NET_F_HOST_UFO);
     }
 
+    if (!peer_has_uso(n)) {
+        virtio_clear_feature(&features, VIRTIO_NET_F_HOST_USO);
+        virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO4);
+        virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO6);
+    }
+
     if (!get_vhost_net(nc->peer)) {
         return features;
     }
diff --git a/include/net/net.h b/include/net/net.h
index b5ccfbbffb..330d285930 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -54,6 +54,7 @@ typedef void (LinkStatusChanged)(NetClientState *);
 typedef void (NetClientDestructor)(NetClientState *);
 typedef RxFilterInfo *(QueryRxFilter)(NetClientState *);
 typedef bool (HasUfo)(NetClientState *);
+typedef bool (HasUso)(NetClientState *);
 typedef bool (HasVnetHdr)(NetClientState *);
 typedef bool (HasVnetHdrLen)(NetClientState *, int);
 typedef bool (GetUsingVnetHdr)(NetClientState *);
@@ -84,6 +85,7 @@ typedef struct NetClientInfo {
     QueryRxFilter *query_rx_filter;
     NetPoll *poll;
     HasUfo *has_ufo;
+    HasUso *has_uso;
     HasVnetHdr *has_vnet_hdr;
     HasVnetHdrLen *has_vnet_hdr_len;
     GetUsingVnetHdr *get_using_vnet_hdr;
@@ -187,6 +189,7 @@ void qemu_set_info_str(NetClientState *nc,
                        const char *fmt, ...) G_GNUC_PRINTF(2, 3);
 void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6]);
 bool qemu_has_ufo(NetClientState *nc);
+bool qemu_has_uso(NetClientState *nc);
 bool qemu_has_vnet_hdr(NetClientState *nc);
 bool qemu_has_vnet_hdr_len(NetClientState *nc, int len);
 bool qemu_get_using_vnet_hdr(NetClientState *nc);
diff --git a/net/net.c b/net/net.c
index 543e6dec43..b110e61f66 100644
--- a/net/net.c
+++ b/net/net.c
@@ -495,6 +495,15 @@ bool qemu_has_ufo(NetClientState *nc)
     return nc->info->has_ufo(nc);
 }
 
+bool qemu_has_uso(NetClientState *nc)
+{
+    if (!nc || !nc->info->has_uso) {
+        return false;
+    }
+
+    return nc->info->has_uso(nc);
+}
+
 bool qemu_has_vnet_hdr(NetClientState *nc)
 {
     if (!nc || !nc->info->has_vnet_hdr) {
diff --git a/net/tap-bsd.c b/net/tap-bsd.c
index abd16a2ad2..274ea7bd2c 100644
--- a/net/tap-bsd.c
+++ b/net/tap-bsd.c
@@ -212,6 +212,11 @@ int tap_probe_has_ufo(int fd)
     return 0;
 }
 
+int tap_probe_has_uso(int fd)
+{
+    return 0;
+}
+
 int tap_probe_vnet_hdr_len(int fd, int len)
 {
     return 0;
diff --git a/net/tap-linux.c b/net/tap-linux.c
index 30fcca1bc2..c7e514ecb0 100644
--- a/net/tap-linux.c
+++ b/net/tap-linux.c
@@ -173,6 +173,18 @@ int tap_probe_has_ufo(int fd)
     return 1;
 }
 
+int tap_probe_has_uso(int fd)
+{
+    unsigned offload;
+
+    offload = TUN_F_CSUM | TUN_F_USO4 | TUN_F_USO6;
+
+    if (ioctl(fd, TUNSETOFFLOAD, offload) < 0) {
+        return 0;
+    }
+    return 1;
+}
+
 /* Verify that we can assign given length */
 int tap_probe_vnet_hdr_len(int fd, int len)
 {
diff --git a/net/tap-solaris.c b/net/tap-solaris.c
index a617a10e5c..08b13af512 100644
--- a/net/tap-solaris.c
+++ b/net/tap-solaris.c
@@ -216,6 +216,11 @@ int tap_probe_has_ufo(int fd)
     return 0;
 }
 
+int tap_probe_has_uso(int fd)
+{
+    return 0;
+}
+
 int tap_probe_vnet_hdr_len(int fd, int len)
 {
     return 0;
diff --git a/net/tap-stub.c b/net/tap-stub.c
index ac8dfc03b4..4b24f61e3a 100644
--- a/net/tap-stub.c
+++ b/net/tap-stub.c
@@ -47,6 +47,11 @@ int tap_probe_has_ufo(int fd)
     return 0;
 }
 
+int tap_probe_has_uso(int fd)
+{
+    return 0;
+}
+
 int tap_probe_vnet_hdr_len(int fd, int len)
 {
     return 0;
diff --git a/net/tap.c b/net/tap.c
index 14ea4ef26f..bcea8d03f9 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -57,6 +57,7 @@ typedef struct TAPState {
     bool write_poll;
     bool using_vnet_hdr;
     bool has_ufo;
+    bool has_uso;
     bool enabled;
     VHostNetState *vhost_net;
     unsigned host_vnet_hdr_len;
@@ -237,6 +238,15 @@ static bool tap_has_ufo(NetClientState *nc)
     return s->has_ufo;
 }
 
+static bool tap_has_uso(NetClientState *nc)
+{
+    TAPState *s = DO_UPCAST(TAPState, nc, nc);
+
+    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
+
+    return s->has_uso;
+}
+
 static bool tap_has_vnet_hdr(NetClientState *nc)
 {
     TAPState *s = DO_UPCAST(TAPState, nc, nc);
@@ -384,6 +394,7 @@ static NetClientInfo net_tap_info = {
     .poll = tap_poll,
     .cleanup = tap_cleanup,
     .has_ufo = tap_has_ufo,
+    .has_uso = tap_has_uso,
     .has_vnet_hdr = tap_has_vnet_hdr,
     .has_vnet_hdr_len = tap_has_vnet_hdr_len,
     .get_using_vnet_hdr = tap_get_using_vnet_hdr,
@@ -413,6 +424,7 @@ static TAPState *net_tap_fd_init(NetClientState *peer,
     s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0;
     s->using_vnet_hdr = false;
     s->has_ufo = tap_probe_has_ufo(s->fd);
+    s->has_uso = tap_probe_has_uso(s->fd);
     s->enabled = true;
     tap_set_offload(&s->nc, 0, 0, 0, 0, 0, 0, 0);
     /*
diff --git a/net/tap_int.h b/net/tap_int.h
index d8861d81ba..9a2175655b 100644
--- a/net/tap_int.h
+++ b/net/tap_int.h
@@ -37,6 +37,7 @@ void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp);
 int tap_probe_vnet_hdr(int fd, Error **errp);
 int tap_probe_vnet_hdr_len(int fd, int len);
 int tap_probe_has_ufo(int fd);
+int tap_probe_has_uso(int fd);
 void tap_fd_set_offload(int fd, int csum, int tso4, int tso6, int ecn, int ufo,
                         int uso4, int uso6);
 void tap_fd_set_vnet_hdr_len(int fd, int len);
-- 
2.34.3

Placing this patch after "[PATCH 3/4] virtio-net: added USO support" may 
interfer with "git bisect" on a host that does not support USO as 
virtio-net can advertise USO support where it's not supported.

I suggest to combine this patch with the earlier patch aforementioned. 
It will make the entire patch big so I think it's also better to extract 
the change for tap into another patch.

On 2023/07/20 0:21, Yuri Benditovich wrote:
> From: Andrew Melnychenko <andrew@daynix.com>
> 
> Added tap uso check with stubs for non-Linux systems.
> 
> Signed-off-by: Yuri Benditovich <yuri.benditovich@daynix.com>
> Signed-off-by: Andrew Melnychenko <andrew@daynix.com>
> ---
>   hw/net/virtio-net.c | 15 +++++++++++++++
>   include/net/net.h   |  3 +++
>   net/net.c           |  9 +++++++++
>   net/tap-bsd.c       |  5 +++++
>   net/tap-linux.c     | 12 ++++++++++++
>   net/tap-solaris.c   |  5 +++++
>   net/tap-stub.c      |  5 +++++
>   net/tap.c           | 12 ++++++++++++
>   net/tap_int.h       |  1 +
>   9 files changed, 67 insertions(+)
> 
> diff --git a/hw/net/virtio-net.c b/hw/net/virtio-net.c
> index e76cad923b..d950d3a77f 100644
> --- a/hw/net/virtio-net.c
> +++ b/hw/net/virtio-net.c
> @@ -659,6 +659,15 @@ static int peer_has_ufo(VirtIONet *n)
>       return n->has_ufo;
>   }
>   
> +static int peer_has_uso(VirtIONet *n)
> +{
> +    if (!peer_has_vnet_hdr(n)) {
> +        return 0;
> +    }
> +
> +    return qemu_has_uso(qemu_get_queue(n->nic)->peer);
> +}
> +
>   static void virtio_net_set_mrg_rx_bufs(VirtIONet *n, int mergeable_rx_bufs,
>                                          int version_1, int hash_report)
>   {
> @@ -808,6 +817,12 @@ static uint64_t virtio_net_get_features(VirtIODevice *vdev, uint64_t features,
>           virtio_clear_feature(&features, VIRTIO_NET_F_HOST_UFO);
>       }
>   
> +    if (!peer_has_uso(n)) {
> +        virtio_clear_feature(&features, VIRTIO_NET_F_HOST_USO);
> +        virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO4);
> +        virtio_clear_feature(&features, VIRTIO_NET_F_GUEST_USO6);
> +    }
> +
>       if (!get_vhost_net(nc->peer)) {
>           return features;
>       }
> diff --git a/include/net/net.h b/include/net/net.h
> index b5ccfbbffb..330d285930 100644
> --- a/include/net/net.h
> +++ b/include/net/net.h
> @@ -54,6 +54,7 @@ typedef void (LinkStatusChanged)(NetClientState *);
>   typedef void (NetClientDestructor)(NetClientState *);
>   typedef RxFilterInfo *(QueryRxFilter)(NetClientState *);
>   typedef bool (HasUfo)(NetClientState *);
> +typedef bool (HasUso)(NetClientState *);
>   typedef bool (HasVnetHdr)(NetClientState *);
>   typedef bool (HasVnetHdrLen)(NetClientState *, int);
>   typedef bool (GetUsingVnetHdr)(NetClientState *);
> @@ -84,6 +85,7 @@ typedef struct NetClientInfo {
>       QueryRxFilter *query_rx_filter;
>       NetPoll *poll;
>       HasUfo *has_ufo;
> +    HasUso *has_uso;
>       HasVnetHdr *has_vnet_hdr;
>       HasVnetHdrLen *has_vnet_hdr_len;
>       GetUsingVnetHdr *get_using_vnet_hdr;
> @@ -187,6 +189,7 @@ void qemu_set_info_str(NetClientState *nc,
>                          const char *fmt, ...) G_GNUC_PRINTF(2, 3);
>   void qemu_format_nic_info_str(NetClientState *nc, uint8_t macaddr[6]);
>   bool qemu_has_ufo(NetClientState *nc);
> +bool qemu_has_uso(NetClientState *nc);
>   bool qemu_has_vnet_hdr(NetClientState *nc);
>   bool qemu_has_vnet_hdr_len(NetClientState *nc, int len);
>   bool qemu_get_using_vnet_hdr(NetClientState *nc);
> diff --git a/net/net.c b/net/net.c
> index 543e6dec43..b110e61f66 100644
> --- a/net/net.c
> +++ b/net/net.c
> @@ -495,6 +495,15 @@ bool qemu_has_ufo(NetClientState *nc)
>       return nc->info->has_ufo(nc);
>   }
>   
> +bool qemu_has_uso(NetClientState *nc)
> +{
> +    if (!nc || !nc->info->has_uso) {
> +        return false;
> +    }
> +
> +    return nc->info->has_uso(nc);
> +}
> +
>   bool qemu_has_vnet_hdr(NetClientState *nc)
>   {
>       if (!nc || !nc->info->has_vnet_hdr) {
> diff --git a/net/tap-bsd.c b/net/tap-bsd.c
> index abd16a2ad2..274ea7bd2c 100644
> --- a/net/tap-bsd.c
> +++ b/net/tap-bsd.c
> @@ -212,6 +212,11 @@ int tap_probe_has_ufo(int fd)
>       return 0;
>   }
>   
> +int tap_probe_has_uso(int fd)
> +{
> +    return 0;
> +}
> +
>   int tap_probe_vnet_hdr_len(int fd, int len)
>   {
>       return 0;
> diff --git a/net/tap-linux.c b/net/tap-linux.c
> index 30fcca1bc2..c7e514ecb0 100644
> --- a/net/tap-linux.c
> +++ b/net/tap-linux.c
> @@ -173,6 +173,18 @@ int tap_probe_has_ufo(int fd)
>       return 1;
>   }
>   
> +int tap_probe_has_uso(int fd)
> +{
> +    unsigned offload;
> +
> +    offload = TUN_F_CSUM | TUN_F_USO4 | TUN_F_USO6;
> +
> +    if (ioctl(fd, TUNSETOFFLOAD, offload) < 0) {
> +        return 0;
> +    }
> +    return 1;
> +}
> +
>   /* Verify that we can assign given length */
>   int tap_probe_vnet_hdr_len(int fd, int len)
>   {
> diff --git a/net/tap-solaris.c b/net/tap-solaris.c
> index a617a10e5c..08b13af512 100644
> --- a/net/tap-solaris.c
> +++ b/net/tap-solaris.c
> @@ -216,6 +216,11 @@ int tap_probe_has_ufo(int fd)
>       return 0;
>   }
>   
> +int tap_probe_has_uso(int fd)
> +{
> +    return 0;
> +}
> +
>   int tap_probe_vnet_hdr_len(int fd, int len)
>   {
>       return 0;
> diff --git a/net/tap-stub.c b/net/tap-stub.c
> index ac8dfc03b4..4b24f61e3a 100644
> --- a/net/tap-stub.c
> +++ b/net/tap-stub.c
> @@ -47,6 +47,11 @@ int tap_probe_has_ufo(int fd)
>       return 0;
>   }
>   
> +int tap_probe_has_uso(int fd)
> +{
> +    return 0;
> +}
> +
>   int tap_probe_vnet_hdr_len(int fd, int len)
>   {
>       return 0;
> diff --git a/net/tap.c b/net/tap.c
> index 14ea4ef26f..bcea8d03f9 100644
> --- a/net/tap.c
> +++ b/net/tap.c
> @@ -57,6 +57,7 @@ typedef struct TAPState {
>       bool write_poll;
>       bool using_vnet_hdr;
>       bool has_ufo;
> +    bool has_uso;
>       bool enabled;
>       VHostNetState *vhost_net;
>       unsigned host_vnet_hdr_len;
> @@ -237,6 +238,15 @@ static bool tap_has_ufo(NetClientState *nc)
>       return s->has_ufo;
>   }
>   
> +static bool tap_has_uso(NetClientState *nc)
> +{
> +    TAPState *s = DO_UPCAST(TAPState, nc, nc);
> +
> +    assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
> +
> +    return s->has_uso;
> +}
> +
>   static bool tap_has_vnet_hdr(NetClientState *nc)
>   {
>       TAPState *s = DO_UPCAST(TAPState, nc, nc);
> @@ -384,6 +394,7 @@ static NetClientInfo net_tap_info = {
>       .poll = tap_poll,
>       .cleanup = tap_cleanup,
>       .has_ufo = tap_has_ufo,
> +    .has_uso = tap_has_uso,
>       .has_vnet_hdr = tap_has_vnet_hdr,
>       .has_vnet_hdr_len = tap_has_vnet_hdr_len,
>       .get_using_vnet_hdr = tap_get_using_vnet_hdr,
> @@ -413,6 +424,7 @@ static TAPState *net_tap_fd_init(NetClientState *peer,
>       s->host_vnet_hdr_len = vnet_hdr ? sizeof(struct virtio_net_hdr) : 0;
>       s->using_vnet_hdr = false;
>       s->has_ufo = tap_probe_has_ufo(s->fd);
> +    s->has_uso = tap_probe_has_uso(s->fd);
>       s->enabled = true;
>       tap_set_offload(&s->nc, 0, 0, 0, 0, 0, 0, 0);
>       /*
> diff --git a/net/tap_int.h b/net/tap_int.h
> index d8861d81ba..9a2175655b 100644
> --- a/net/tap_int.h
> +++ b/net/tap_int.h
> @@ -37,6 +37,7 @@ void tap_set_sndbuf(int fd, const NetdevTapOptions *tap, Error **errp);
>   int tap_probe_vnet_hdr(int fd, Error **errp);
>   int tap_probe_vnet_hdr_len(int fd, int len);
>   int tap_probe_has_ufo(int fd);
> +int tap_probe_has_uso(int fd);
>   void tap_fd_set_offload(int fd, int csum, int tso4, int tso6, int ecn, int ufo,
>                           int uso4, int uso6);
>   void tap_fd_set_vnet_hdr_len(int fd, int len);