vhost-user: introduce shared vhost-user state

When multi queue is enabled e.g. for a virtio-net device,
each queue pair will have a vhost_dev, and the only thing
shared between vhost devs currently is the chardev. This
patch introduces a vhost-user state structure which will
be shared by all vhost devs of the same virtio device.

Signed-off-by: Tiwei Bie <tiwei.bie@intel.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

3 files changed, 33 insertions, 10 deletions

diff --git a/hw/virtio/Makefile.objs b/hw/virtio/Makefile.objs
index 765d363c1f..030969e28c 100644
--- a/hw/virtio/Makefile.objs
+++ b/hw/virtio/Makefile.objs
@@ -11,5 +11,5 @@ obj-y += virtio-crypto.o
 obj-$(CONFIG_VIRTIO_PCI) += virtio-crypto-pci.o
 endif
 
-common-obj-$(call lnot,$(CONFIG_LINUX)) += vhost-stub.o
+common-obj-$(call lnot,$(call land,$(CONFIG_VIRTIO),$(CONFIG_LINUX))) += vhost-stub.o
 common-obj-$(CONFIG_ALL) += vhost-stub.o
diff --git a/hw/virtio/vhost-stub.c b/hw/virtio/vhost-stub.c
index 2d76cdebdc..049089b5e2 100644
--- a/hw/virtio/vhost-stub.c
+++ b/hw/virtio/vhost-stub.c
@@ -1,7 +1,17 @@
 #include "qemu/osdep.h"
 #include "hw/virtio/vhost.h"
+#include "hw/virtio/vhost-user.h"
 
 bool vhost_has_free_slot(void)
 {
     return true;
 }
+
+VhostUserState *vhost_user_init(void)
+{
+    return NULL;
+}
+
+void vhost_user_cleanup(VhostUserState *user)
+{
+}
diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c
index 75a3faef2a..70b9610c87 100644
--- a/hw/virtio/vhost-user.c
+++ b/hw/virtio/vhost-user.c
@@ -11,6 +11,7 @@
 #include "qemu/osdep.h"
 #include "qapi/error.h"
 #include "hw/virtio/vhost.h"
+#include "hw/virtio/vhost-user.h"
 #include "hw/virtio/vhost-backend.h"
 #include "hw/virtio/virtio-net.h"
 #include "chardev/char-fe.h"
@@ -175,7 +176,8 @@ static VhostUserMsg m __attribute__ ((unused));
 
 struct vhost_user {
     struct vhost_dev *dev;
-    CharBackend *chr;
+    /* Shared between vhost devs of the same virtio device */
+    VhostUserState *user;
     int slave_fd;
     NotifierWithReturn postcopy_notifier;
     struct PostCopyFD  postcopy_fd;
@@ -201,7 +203,7 @@ static bool ioeventfd_enabled(void)
 static int vhost_user_read(struct vhost_dev *dev, VhostUserMsg *msg)
 {
     struct vhost_user *u = dev->opaque;
-    CharBackend *chr = u->chr;
+    CharBackend *chr = u->user->chr;
     uint8_t *p = (uint8_t *) msg;
     int r, size = VHOST_USER_HDR_SIZE;
 
@@ -287,7 +289,7 @@ static int vhost_user_write(struct vhost_dev *dev, VhostUserMsg *msg,
                             int *fds, int fd_num)
 {
     struct vhost_user *u = dev->opaque;
-    CharBackend *chr = u->chr;
+    CharBackend *chr = u->user->chr;
     int ret, size = VHOST_USER_HDR_SIZE + msg->hdr.size;
 
     /*
@@ -1090,7 +1092,7 @@ static int vhost_user_postcopy_waker(struct PostCopyFD *pcfd, RAMBlock *rb,
 static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp)
 {
     struct vhost_user *u = dev->opaque;
-    CharBackend *chr = u->chr;
+    CharBackend *chr = u->user->chr;
     int ufd;
     VhostUserMsg msg = {
         .hdr.request = VHOST_USER_POSTCOPY_ADVISE,
@@ -1228,7 +1230,7 @@ static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier,
     return 0;
 }
 
-static int vhost_user_init(struct vhost_dev *dev, void *opaque)
+static int vhost_user_backend_init(struct vhost_dev *dev, void *opaque)
 {
     uint64_t features, protocol_features;
     struct vhost_user *u;
@@ -1237,7 +1239,7 @@ static int vhost_user_init(struct vhost_dev *dev, void *opaque)
     assert(dev->vhost_ops->backend_type == VHOST_BACKEND_TYPE_USER);
 
     u = g_new0(struct vhost_user, 1);
-    u->chr = opaque;
+    u->user = opaque;
     u->slave_fd = -1;
     u->dev = dev;
     dev->opaque = u;
@@ -1313,7 +1315,7 @@ static int vhost_user_init(struct vhost_dev *dev, void *opaque)
     return 0;
 }
 
-static int vhost_user_cleanup(struct vhost_dev *dev)
+static int vhost_user_backend_cleanup(struct vhost_dev *dev)
 {
     struct vhost_user *u;
 
@@ -1637,10 +1639,21 @@ static bool vhost_user_mem_section_filter(struct vhost_dev *dev,
     return result;
 }
 
+VhostUserState *vhost_user_init(void)
+{
+    VhostUserState *user = g_new0(struct VhostUserState, 1);
+
+    return user;
+}
+
+void vhost_user_cleanup(VhostUserState *user)
+{
+}
+
 const VhostOps user_ops = {
         .backend_type = VHOST_BACKEND_TYPE_USER,
-        .vhost_backend_init = vhost_user_init,
-        .vhost_backend_cleanup = vhost_user_cleanup,
+        .vhost_backend_init = vhost_user_backend_init,
+        .vhost_backend_cleanup = vhost_user_backend_cleanup,
         .vhost_backend_memslots_limit = vhost_user_memslots_limit,
         .vhost_set_log_base = vhost_user_set_log_base,
         .vhost_set_mem_table = vhost_user_set_mem_table,