[PATCH 08/10] vhost: move msg_handler to new ops struct

[Mike Christie]

The next patch adds a callout so drivers can perform some action when we
get a VHOST_SET_VRING_ENABLE, so this patch moves the msg_handler callout
to a new vhost_dev_ops struct just to keep all the callouts better
organized.

Signed-off-by: Mike Christie <michael.christie@oracle.com>
---
 drivers/vhost/vdpa.c  |  7 +++++--
 drivers/vhost/vhost.c | 10 ++++------
 drivers/vhost/vhost.h | 11 ++++++-----
 3 files changed, 15 insertions(+), 13 deletions(-)

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 2754f30..f271f42 100644
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -802,6 +802,10 @@ static void vhost_vdpa_set_iova_range(struct vhost_vdpa *v)
        }
 }
 
+static struct vhost_dev_ops vdpa_dev_ops = {
+       .msg_handler    = vhost_vdpa_process_iotlb_msg,
+};
+
 static int vhost_vdpa_open(struct inode *inode, struct file *filep)
 {
        struct vhost_vdpa *v;
@@ -829,8 +833,7 @@ static int vhost_vdpa_open(struct inode *inode, struct file 
*filep)
                vqs[i] = &v->vqs[i];
                vqs[i]->handle_kick = handle_vq_kick;
        }
-       vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false,
-                      vhost_vdpa_process_iotlb_msg);
+       vhost_dev_init(dev, vqs, nvqs, 0, 0, 0, false, &vdpa_dev_ops);
 
        dev->iotlb = vhost_iotlb_alloc(0, 0);
        if (!dev->iotlb) {
diff --git a/drivers/vhost/vhost.c b/drivers/vhost/vhost.c
index 6a6abfc..2f98b81 100644
--- a/drivers/vhost/vhost.c
+++ b/drivers/vhost/vhost.c
@@ -504,9 +504,7 @@ static size_t vhost_get_desc_size(struct vhost_virtqueue 
*vq,
 void vhost_dev_init(struct vhost_dev *dev,
                    struct vhost_virtqueue **vqs, int nvqs,
                    int iov_limit, int weight, int byte_weight,
-                   bool use_worker,
-                   int (*msg_handler)(struct vhost_dev *dev,
-                                      struct vhost_iotlb_msg *msg))
+                   bool use_worker, struct vhost_dev_ops *ops)
 {
        struct vhost_virtqueue *vq;
        int i;
@@ -524,7 +522,7 @@ void vhost_dev_init(struct vhost_dev *dev,
        dev->weight = weight;
        dev->byte_weight = byte_weight;
        dev->use_worker = use_worker;
-       dev->msg_handler = msg_handler;
+       dev->ops = ops;
        init_waitqueue_head(&dev->wait);
        INIT_LIST_HEAD(&dev->read_list);
        INIT_LIST_HEAD(&dev->pending_list);
@@ -1328,8 +1326,8 @@ ssize_t vhost_chr_write_iter(struct vhost_dev *dev,
                goto done;
        }
 
-       if (dev->msg_handler)
-               ret = dev->msg_handler(dev, &msg);
+       if (dev->ops && dev->ops->msg_handler)
+               ret = dev->ops->msg_handler(dev, &msg);
        else
                ret = vhost_process_iotlb_msg(dev, &msg);
        if (ret) {
diff --git a/drivers/vhost/vhost.h b/drivers/vhost/vhost.h
index 0837133..a293f48 100644
--- a/drivers/vhost/vhost.h
+++ b/drivers/vhost/vhost.h
@@ -156,6 +156,10 @@ struct vhost_msg_node {
   struct list_head node;
 };
 
+struct vhost_dev_ops {
+       int (*msg_handler)(struct vhost_dev *dev, struct vhost_iotlb_msg *msg);
+};
+
 struct vhost_dev {
        struct mm_struct *mm;
        struct mutex mutex;
@@ -175,16 +179,13 @@ struct vhost_dev {
        int byte_weight;
        u64 kcov_handle;
        bool use_worker;
-       int (*msg_handler)(struct vhost_dev *dev,
-                          struct vhost_iotlb_msg *msg);
+       struct vhost_dev_ops *ops;
 };
 
 bool vhost_exceeds_weight(struct vhost_virtqueue *vq, int pkts, int total_len);
 void vhost_dev_init(struct vhost_dev *, struct vhost_virtqueue **vqs,
                    int nvqs, int iov_limit, int weight, int byte_weight,
-                   bool use_worker,
-                   int (*msg_handler)(struct vhost_dev *dev,
-                                      struct vhost_iotlb_msg *msg));
+                   bool use_worker, struct vhost_dev_ops *ops);
 long vhost_dev_set_owner(struct vhost_dev *dev);
 bool vhost_dev_has_owner(struct vhost_dev *dev);
 long vhost_dev_check_owner(struct vhost_dev *);
-- 
1.8.3.1