IB/mlx5: Use the ucontext from the uobj, not the file

This approach matches the standard flow of the typical write method that
relies on the HW object to store the device and the uobject to access the
ucontext.  Avoids the use of the devx_ufile2uctx in several places will
make revising the semantics of ib_uverbs_get_ucontext() in the next patch
simpler.

Signed-off-by: Jason Gunthorpe <jgg@mellanox.com>
diff --git a/drivers/infiniband/hw/mlx5/devx.c b/drivers/infiniband/hw/mlx5/devx.c
index 270452c..98b1575 100644
--- a/drivers/infiniband/hw/mlx5/devx.c
+++ b/drivers/infiniband/hw/mlx5/devx.c
@@ -706,13 +706,14 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_CREATE)(struct ib_device *ib_d
 				   struct ib_uverbs_file *file,
 				   struct uverbs_attr_bundle *attrs)
 {
-	struct mlx5_ib_ucontext *c = devx_ufile2uctx(file);
-	struct mlx5_ib_dev *dev = to_mdev(ib_dev);
 	void *cmd_in = uverbs_attr_get_alloced_ptr(attrs, MLX5_IB_ATTR_DEVX_OBJ_CREATE_CMD_IN);
 	int cmd_out_len =  uverbs_attr_get_len(attrs,
 					MLX5_IB_ATTR_DEVX_OBJ_CREATE_CMD_OUT);
 	void *cmd_out;
-	struct ib_uobject *uobj;
+	struct ib_uobject *uobj = uverbs_attr_get_uobject(
+		attrs, MLX5_IB_ATTR_DEVX_OBJ_CREATE_HANDLE);
+	struct mlx5_ib_ucontext *c = to_mucontext(uobj->context);
+	struct mlx5_ib_dev *dev = to_mdev(c->ibucontext.device);
 	struct devx_obj *obj;
 	int err;
 
@@ -739,7 +740,6 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_CREATE)(struct ib_device *ib_d
 	if (err)
 		goto cmd_free;
 
-	uobj = uverbs_attr_get_uobject(attrs, MLX5_IB_ATTR_DEVX_OBJ_CREATE_HANDLE);
 	uobj->object = obj;
 	obj->mdev = dev->mdev;
 	devx_obj_build_destroy_cmd(cmd_in, cmd_out, obj->dinbox, &obj->dinlen, &obj->obj_id);
@@ -763,13 +763,13 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_MODIFY)(struct ib_device *ib_d
 				   struct ib_uverbs_file *file,
 				   struct uverbs_attr_bundle *attrs)
 {
-	struct mlx5_ib_ucontext *c = devx_ufile2uctx(file);
-	struct mlx5_ib_dev *dev = to_mdev(ib_dev);
 	void *cmd_in = uverbs_attr_get_alloced_ptr(attrs, MLX5_IB_ATTR_DEVX_OBJ_MODIFY_CMD_IN);
 	int cmd_out_len = uverbs_attr_get_len(attrs,
 					MLX5_IB_ATTR_DEVX_OBJ_MODIFY_CMD_OUT);
 	struct ib_uobject *uobj = uverbs_attr_get_uobject(attrs,
 							  MLX5_IB_ATTR_DEVX_OBJ_MODIFY_HANDLE);
+	struct mlx5_ib_ucontext *c = to_mucontext(uobj->context);
+	struct devx_obj *obj = uobj->object;
 	void *cmd_out;
 	int err;
 
@@ -779,7 +779,7 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_MODIFY)(struct ib_device *ib_d
 	if (!devx_is_obj_modify_cmd(cmd_in))
 		return -EINVAL;
 
-	if (!devx_is_valid_obj_id(uobj->object, cmd_in))
+	if (!devx_is_valid_obj_id(obj, cmd_in))
 		return -EINVAL;
 
 	cmd_out = kvzalloc(cmd_out_len, GFP_KERNEL);
@@ -787,7 +787,7 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_MODIFY)(struct ib_device *ib_d
 		return -ENOMEM;
 
 	MLX5_SET(general_obj_in_cmd_hdr, cmd_in, uid, c->devx_uid);
-	err = mlx5_cmd_exec(dev->mdev, cmd_in,
+	err = mlx5_cmd_exec(obj->mdev, cmd_in,
 			    uverbs_attr_get_len(attrs, MLX5_IB_ATTR_DEVX_OBJ_MODIFY_CMD_IN),
 			    cmd_out, cmd_out_len);
 	if (err)
@@ -805,13 +805,13 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_QUERY)(struct ib_device *ib_de
 				   struct ib_uverbs_file *file,
 				   struct uverbs_attr_bundle *attrs)
 {
-	struct mlx5_ib_ucontext *c = devx_ufile2uctx(file);
-	struct mlx5_ib_dev *dev = to_mdev(ib_dev);
 	void *cmd_in = uverbs_attr_get_alloced_ptr(attrs, MLX5_IB_ATTR_DEVX_OBJ_QUERY_CMD_IN);
 	int cmd_out_len = uverbs_attr_get_len(attrs,
 					      MLX5_IB_ATTR_DEVX_OBJ_QUERY_CMD_OUT);
 	struct ib_uobject *uobj = uverbs_attr_get_uobject(attrs,
 							  MLX5_IB_ATTR_DEVX_OBJ_QUERY_HANDLE);
+	struct mlx5_ib_ucontext *c = to_mucontext(uobj->context);
+	struct devx_obj *obj = uobj->object;
 	void *cmd_out;
 	int err;
 
@@ -821,7 +821,7 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_QUERY)(struct ib_device *ib_de
 	if (!devx_is_obj_query_cmd(cmd_in))
 		return -EINVAL;
 
-	if (!devx_is_valid_obj_id(uobj->object, cmd_in))
+	if (!devx_is_valid_obj_id(obj, cmd_in))
 		return -EINVAL;
 
 	cmd_out = kvzalloc(cmd_out_len, GFP_KERNEL);
@@ -829,7 +829,7 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_OBJ_QUERY)(struct ib_device *ib_de
 		return -ENOMEM;
 
 	MLX5_SET(general_obj_in_cmd_hdr, cmd_in, uid, c->devx_uid);
-	err = mlx5_cmd_exec(dev->mdev, cmd_in,
+	err = mlx5_cmd_exec(obj->mdev, cmd_in,
 			    uverbs_attr_get_len(attrs, MLX5_IB_ATTR_DEVX_OBJ_QUERY_CMD_IN),
 			    cmd_out, cmd_out_len);
 	if (err)
@@ -920,18 +920,18 @@ static int UVERBS_HANDLER(MLX5_IB_METHOD_DEVX_UMEM_REG)(struct ib_device *ib_dev
 				 struct ib_uverbs_file *file,
 				 struct uverbs_attr_bundle *attrs)
 {
-	struct mlx5_ib_ucontext *c = devx_ufile2uctx(file);
-	struct mlx5_ib_dev *dev = to_mdev(ib_dev);
 	struct devx_umem_reg_cmd cmd;
 	struct devx_umem *obj;
-	struct ib_uobject *uobj;
+	struct ib_uobject *uobj = uverbs_attr_get_uobject(
+		attrs, MLX5_IB_ATTR_DEVX_UMEM_REG_HANDLE);
 	u32 obj_id;
+	struct mlx5_ib_ucontext *c = to_mucontext(uobj->context);
+	struct mlx5_ib_dev *dev = to_mdev(c->ibucontext.device);
 	int err;
 
 	if (!c->devx_uid)
 		return -EPERM;
 
-	uobj = uverbs_attr_get_uobject(attrs, MLX5_IB_ATTR_DEVX_UMEM_REG_HANDLE);
 	obj = kzalloc(sizeof(struct devx_umem), GFP_KERNEL);
 	if (!obj)
 		return -ENOMEM;