The get_vhost_net() function previously contained a large switch
statement to find the VHostNetState pointer based on the net
client's type. This created a tight coupling, requiring the generic
vhost layer to be aware of every specific backend that supported
vhost, such as tap, vhost-user, and vhost-vdpa.
This approach is not scalable and requires modifying a central function
for any new backend. It also forced each backend to expose its internal
getter function in a public header file.
This patch refactors the logic by introducing a new get_vhost_net
function pointer to the NetClientInfo struct. The central
get_vhost_net() function is now a simple, generic dispatcher that
invokes the callback provided by the net client.
Each backend now implements its own private getter and registers it in
its NetClientInfo.
Signed-off-by: Laurent Vivier <lvivier@redhat.com>
---
hw/net/vhost_net.c | 31 ++++---------------------------
include/net/net.h | 2 ++
include/net/tap.h | 3 ---
include/net/vhost-user.h | 1 -
include/net/vhost-vdpa.h | 2 --
net/tap-win32.c | 5 -----
net/tap.c | 20 +++++++++++++-------
net/vhost-user.c | 3 ++-
net/vhost-vdpa.c | 4 +++-
9 files changed, 24 insertions(+), 47 deletions(-)
diff --git a/hw/net/vhost_net.c b/hw/net/vhost_net.c
index 41d21e687ed9..16dadd022e75 100644
--- a/hw/net/vhost_net.c
+++ b/hw/net/vhost_net.c
@@ -646,41 +646,18 @@ void vhost_net_config_mask(VHostNetState *net, VirtIODevice *dev, bool mask)
{
vhost_config_mask(&net->dev, dev, mask);
}
+
VHostNetState *get_vhost_net(NetClientState *nc)
{
- VHostNetState *vhost_net = 0;
-
if (!nc) {
return 0;
}
- switch (nc->info->type) {
- case NET_CLIENT_DRIVER_TAP:
- vhost_net = tap_get_vhost_net(nc);
- /*
- * tap_get_vhost_net() can return NULL if a tap net-device backend is
- * created with 'vhost=off' option, 'vhostforce=off' or no vhost or
- * vhostforce or vhostfd options at all. Please see net_init_tap_one().
- * Hence, we omit the assertion here.
- */
- break;
-#ifdef CONFIG_VHOST_NET_USER
- case NET_CLIENT_DRIVER_VHOST_USER:
- vhost_net = vhost_user_get_vhost_net(nc);
- assert(vhost_net);
- break;
-#endif
-#ifdef CONFIG_VHOST_NET_VDPA
- case NET_CLIENT_DRIVER_VHOST_VDPA:
- vhost_net = vhost_vdpa_get_vhost_net(nc);
- assert(vhost_net);
- break;
-#endif
- default:
- break;
+ if (nc->info->get_vhost_net) {
+ return nc->info->get_vhost_net(nc);
}
- return vhost_net;
+ return NULL;
}
int vhost_set_vring_enable(NetClientState *nc, int enable)
diff --git a/include/net/net.h b/include/net/net.h
index 2c3b22f564b6..8a62cd6e8aab 100644
--- a/include/net/net.h
+++ b/include/net/net.h
@@ -68,6 +68,7 @@ typedef void (NetAnnounce)(NetClientState *);
typedef bool (SetSteeringEBPF)(NetClientState *, int);
typedef bool (NetCheckPeerType)(NetClientState *, ObjectClass *, Error **);
typedef bool (IsVHostUser)(NetClientState *);
+typedef struct vhost_net *(GetVHostNet)(NetClientState *nc);
typedef struct NetClientInfo {
NetClientDriver type;
@@ -94,6 +95,7 @@ typedef struct NetClientInfo {
SetSteeringEBPF *set_steering_ebpf;
NetCheckPeerType *check_peer_type;
IsVHostUser *is_vhost_user;
+ GetVHostNet *get_vhost_net;
} NetClientInfo;
struct NetClientState {
diff --git a/include/net/tap.h b/include/net/tap.h
index 5d585515f9e3..6f34f13eae44 100644
--- a/include/net/tap.h
+++ b/include/net/tap.h
@@ -33,7 +33,4 @@ int tap_disable(NetClientState *nc);
int tap_get_fd(NetClientState *nc);
-struct vhost_net;
-struct vhost_net *tap_get_vhost_net(NetClientState *nc);
-
#endif /* QEMU_NET_TAP_H */
diff --git a/include/net/vhost-user.h b/include/net/vhost-user.h
index 35bf61970985..0b233a267345 100644
--- a/include/net/vhost-user.h
+++ b/include/net/vhost-user.h
@@ -12,7 +12,6 @@
#define VHOST_USER_H
struct vhost_net;
-struct vhost_net *vhost_user_get_vhost_net(NetClientState *nc);
uint64_t vhost_user_get_acked_features(NetClientState *nc);
void vhost_user_save_acked_features(NetClientState *nc);
diff --git a/include/net/vhost-vdpa.h b/include/net/vhost-vdpa.h
index b81f9a6f2a0e..916ead3793d9 100644
--- a/include/net/vhost-vdpa.h
+++ b/include/net/vhost-vdpa.h
@@ -14,8 +14,6 @@
#define TYPE_VHOST_VDPA "vhost-vdpa"
-struct vhost_net *vhost_vdpa_get_vhost_net(NetClientState *nc);
-
extern const int vdpa_feature_bits[];
#endif /* VHOST_VDPA_H */
diff --git a/net/tap-win32.c b/net/tap-win32.c
index 671dee970f7a..38baf90e0b3f 100644
--- a/net/tap-win32.c
+++ b/net/tap-win32.c
@@ -704,11 +704,6 @@ static void tap_win32_send(void *opaque)
}
}
-struct vhost_net *tap_get_vhost_net(NetClientState *nc)
-{
- return NULL;
-}
-
static NetClientInfo net_tap_win32_info = {
.type = NET_CLIENT_DRIVER_TAP,
.size = sizeof(TAPState),
diff --git a/net/tap.c b/net/tap.c
index ae1c7e398321..4beba6d7a784 100644
--- a/net/tap.c
+++ b/net/tap.c
@@ -329,6 +329,18 @@ int tap_get_fd(NetClientState *nc)
return s->fd;
}
+/*
+ * tap_get_vhost_net() can return NULL if a tap net-device backend is
+ * created with 'vhost=off' option, 'vhostforce=off' or no vhost or
+ * vhostforce or vhostfd options at all. Please see net_init_tap_one().
+ */
+static VHostNetState *tap_get_vhost_net(NetClientState *nc)
+{
+ TAPState *s = DO_UPCAST(TAPState, nc, nc);
+ assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
+ return s->vhost_net;
+}
+
/* fd support */
static NetClientInfo net_tap_info = {
@@ -347,6 +359,7 @@ static NetClientInfo net_tap_info = {
.set_vnet_le = tap_set_vnet_le,
.set_vnet_be = tap_set_vnet_be,
.set_steering_ebpf = tap_set_steering_ebpf,
+ .get_vhost_net = tap_get_vhost_net,
};
static TAPState *net_tap_fd_init(NetClientState *peer,
@@ -980,13 +993,6 @@ free_fail:
return 0;
}
-VHostNetState *tap_get_vhost_net(NetClientState *nc)
-{
- TAPState *s = DO_UPCAST(TAPState, nc, nc);
- assert(nc->info->type == NET_CLIENT_DRIVER_TAP);
- return s->vhost_net;
-}
-
int tap_enable(NetClientState *nc)
{
TAPState *s = DO_UPCAST(TAPState, nc, nc);
diff --git a/net/vhost-user.c b/net/vhost-user.c
index 4b4d02c56740..2caa7e56f7a0 100644
--- a/net/vhost-user.c
+++ b/net/vhost-user.c
@@ -32,7 +32,7 @@ typedef struct NetVhostUserState {
bool started;
} NetVhostUserState;
-VHostNetState *vhost_user_get_vhost_net(NetClientState *nc)
+static struct vhost_net *vhost_user_get_vhost_net(NetClientState *nc)
{
NetVhostUserState *s = DO_UPCAST(NetVhostUserState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_USER);
@@ -239,6 +239,7 @@ static NetClientInfo net_vhost_user_info = {
.set_vnet_le = vhost_user_set_vnet_endianness,
.check_peer_type = vhost_user_check_peer_type,
.is_vhost_user = vhost_user_is_vhost_user,
+ .get_vhost_net = vhost_user_get_vhost_net,
};
static gboolean net_vhost_user_watch(void *do_not_use, GIOCondition cond,
diff --git a/net/vhost-vdpa.c b/net/vhost-vdpa.c
index 58d738945dbc..0b86c917ed68 100644
--- a/net/vhost-vdpa.c
+++ b/net/vhost-vdpa.c
@@ -132,7 +132,7 @@ static const uint64_t vdpa_svq_device_features =
#define VHOST_VDPA_NET_CVQ_ASID 1
-VHostNetState *vhost_vdpa_get_vhost_net(NetClientState *nc)
+static struct vhost_net *vhost_vdpa_get_vhost_net(NetClientState *nc)
{
VhostVDPAState *s = DO_UPCAST(VhostVDPAState, nc, nc);
assert(nc->info->type == NET_CLIENT_DRIVER_VHOST_VDPA);
@@ -432,6 +432,7 @@ static NetClientInfo net_vhost_vdpa_info = {
.set_vnet_le = vhost_vdpa_set_vnet_le,
.check_peer_type = vhost_vdpa_check_peer_type,
.set_steering_ebpf = vhost_vdpa_set_steering_ebpf,
+ .get_vhost_net = vhost_vdpa_get_vhost_net,
};
static int64_t vhost_vdpa_get_vring_group(int device_fd, unsigned vq_index,
@@ -1287,6 +1288,7 @@ static NetClientInfo net_vhost_vdpa_cvq_info = {
.has_ufo = vhost_vdpa_has_ufo,
.check_peer_type = vhost_vdpa_check_peer_type,
.set_steering_ebpf = vhost_vdpa_set_steering_ebpf,
+ .get_vhost_net = vhost_vdpa_get_vhost_net,
};
/*
--
2.49.0