Doorbell is a mechanism by which a parent partition can register for
notification if a specified mmio address is touched by a child partition.
Parent partition can setup the notification by specifying mmio address,
size of the data written(1/2/4/8 bytes) and optionally the data as well.
APIs for registering and unregistering doorbell notification.
Signed-off-by: Vineeth Pillai <viremana@xxxxxxxxxxxxxxxxxxx>
---
drivers/hv/hv_synic.c | 81 +++++++++++++++++++++++++++++++++++++++++++
drivers/hv/mshv.h | 4 +++
2 files changed, 85 insertions(+)
diff --git a/drivers/hv/hv_synic.c b/drivers/hv/hv_synic.c
index e3262f6d3daa..af6653967209 100644
--- a/drivers/hv/hv_synic.c
+++ b/drivers/hv/hv_synic.c
@@ -9,6 +9,7 @@
*/
#include <linux/kernel.h>
+#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/io.h>
#include <linux/random.h>
@@ -389,3 +390,83 @@ int mshv_synic_cleanup(unsigned int cpu)
return 0;
}
+
+int
+hv_register_doorbell(u64 partition_id, doorbell_cb_t doorbell_cb, void *data,
+ u64 gpa, u64 val, u64 flags)
+{
+ struct hv_connection_info connection_info = { 0 };
+ union hv_connection_id connection_id = { 0 };
+ struct port_table_info *port_table_info;
+ struct hv_port_info port_info = { 0 };
+ union hv_port_id port_id = { 0 };
+ int ret;
+
+ port_table_info = kmalloc(sizeof(struct port_table_info),
+ GFP_KERNEL);
+ if (!port_table_info)
+ return -ENOMEM;
+
+ port_table_info->port_type = HV_PORT_TYPE_DOORBELL;
+ port_table_info->port_doorbell.doorbell_cb = doorbell_cb;
+ port_table_info->port_doorbell.data = data;
+ ret = hv_portid_alloc(port_table_info);
+ if (ret < 0) {
+ pr_err("Failed to create the doorbell port!\n");
+ kfree(port_table_info);
+ return ret;
+ }
+
+ port_id.u.id = ret;
+ port_info.port_type = HV_PORT_TYPE_DOORBELL;
+ port_info.doorbell_port_info.target_sint = HV_SYNIC_DOORBELL_SINT_INDEX;
+ port_info.doorbell_port_info.target_vp = HV_ANY_VP;
+ ret = hv_call_create_port(hv_current_partition_id, port_id, partition_id,
+ &port_info,
+ 0, 0, NUMA_NO_NODE);
+
+ if (ret < 0) {
+ pr_err("Failed to create the port!\n");
+ hv_portid_free(port_id.u.id);
+ return ret;
+ }
+
+ connection_id.u.id = port_id.u.id;
+ connection_info.port_type = HV_PORT_TYPE_DOORBELL;
+ connection_info.doorbell_connection_info.gpa = gpa;
+ connection_info.doorbell_connection_info.trigger_value = val;
+ connection_info.doorbell_connection_info.flags = flags;
+
+ ret = hv_call_connect_port(hv_current_partition_id, port_id, partition_id,
+ connection_id, &connection_info, 0, NUMA_NO_NODE);
+ if (ret < 0) {
+ hv_call_delete_port(hv_current_partition_id, port_id);
+ hv_portid_free(port_id.u.id);
+ return ret;
+ }
+
+ // lets use the port_id as the doorbell_id
+ return port_id.u.id;
+}
+
+int
+hv_unregister_doorbell(u64 partition_id, int doorbell_portid)
+{
+ int ret = 0;
+ union hv_port_id port_id = { 0 };
+ union hv_connection_id connection_id = { 0 };
+
+ connection_id.u.id = doorbell_portid;
+ ret = hv_call_disconnect_port(partition_id, connection_id);
+ if (ret < 0)
+ pr_err("Failed to disconnect the doorbell connection!\n");
+
+ port_id.u.id = doorbell_portid;
+ ret = hv_call_delete_port(hv_current_partition_id, port_id);
+ if (ret < 0)
+ pr_err("Failed to disconnect the doorbell connection!\n");
+
+ hv_portid_free(doorbell_portid);
+
+ return ret;
+}
diff --git a/drivers/hv/mshv.h b/drivers/hv/mshv.h
index 07b0e7865a4c..76cd00fd4b3f 100644
--- a/drivers/hv/mshv.h
+++ b/drivers/hv/mshv.h
@@ -74,6 +74,10 @@ int hv_portid_alloc(struct port_table_info *info);
int hv_portid_lookup(int port_id, struct port_table_info *info);
void hv_portid_free(int port_id);
+int hv_register_doorbell(u64 partition_id, doorbell_cb_t doorbell_cb,
+ void *data, u64 gpa, u64 val, u64 flags);
+int hv_unregister_doorbell(u64 partition_id, int doorbell_portid);
+
/*
* Hyper-V hypercalls
*/
--
2.25.1
