drivers:hv: Export the API to invoke a hypercall on Hyper-V

This patch exposes the function that hv_vmbus.ko uses to make hypercalls.  This
is necessary for retargeting an interrupt when it is given a new affinity.

Since we are exporting this API, rename the API as it will be visible outside
the hv.c file.

Signed-off-by: Jake Oshins <jakeo@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/hv/hv.c b/drivers/hv/hv.c
index ad7fc6d..eb4e383 100644 (file)
--- a/drivers/hv/hv.c
+++ b/drivers/hv/hv.c
@@ -89,9 +89,9 @@ static int query_hypervisor_info(void)
 }
 
 /*
- * do_hypercall- Invoke the specified hypercall
+ * hv_do_hypercall- Invoke the specified hypercall
  */
-static u64 do_hypercall(u64 control, void *input, void *output)
+u64 hv_do_hypercall(u64 control, void *input, void *output)
 {
        u64 input_address = (input) ? virt_to_phys(input) : 0;
        u64 output_address = (output) ? virt_to_phys(output) : 0;
@@ -132,6 +132,7 @@ static u64 do_hypercall(u64 control, void *input, void *output)
        return hv_status_lo | ((u64)hv_status_hi << 32);
 #endif /* !x86_64 */
 }
+EXPORT_SYMBOL_GPL(hv_do_hypercall);
 
 #ifdef CONFIG_X86_64
 static cycle_t read_hv_clock_tsc(struct clocksource *arg)
@@ -316,7 +317,7 @@ int hv_post_message(union hv_connection_id connection_id,
 {
 
        struct hv_input_post_message *aligned_msg;
-       u16 status;
+       u64 status;
 
        if (payload_size > HV_MESSAGE_PAYLOAD_BYTE_COUNT)
                return -EMSGSIZE;
@@ -330,11 +331,10 @@ int hv_post_message(union hv_connection_id connection_id,
        aligned_msg->payload_size = payload_size;
        memcpy((void *)aligned_msg->payload, payload, payload_size);
 
-       status = do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL)
-               & 0xFFFF;
+       status = hv_do_hypercall(HVCALL_POST_MESSAGE, aligned_msg, NULL);
 
        put_cpu();
-       return status;
+       return status & 0xFFFF;
 }
 
 
@@ -344,13 +344,13 @@ int hv_post_message(union hv_connection_id connection_id,
  *
  * This involves a hypercall.
  */
-u16 hv_signal_event(void *con_id)
+int hv_signal_event(void *con_id)
 {
-       u16 status;
+       u64 status;
 
-       status = (do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL) & 0xFFFF);
+       status = hv_do_hypercall(HVCALL_SIGNAL_EVENT, con_id, NULL);
 
-       return status;
+       return status & 0xFFFF;
 }
 
 static int hv_ce_set_next_event(unsigned long delta,

diff --git a/drivers/hv/hyperv_vmbus.h b/drivers/hv/hyperv_vmbus.h
index 12156db..9beeb14 100644 (file)
--- a/drivers/hv/hyperv_vmbus.h
+++ b/drivers/hv/hyperv_vmbus.h
@@ -587,7 +587,7 @@ extern int hv_post_message(union hv_connection_id connection_id,
                         enum hv_message_type message_type,
                         void *payload, size_t payload_size);
 
-extern u16 hv_signal_event(void *con_id);
+extern int hv_signal_event(void *con_id);
 
 extern int hv_synic_alloc(void);
 

diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index fddb3e0..24d0b65 100644 (file)
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -984,6 +984,7 @@ int vmbus_allocate_mmio(struct resource **new, struct hv_device *device_obj,
                        bool fb_overlap_ok);
 
 int vmbus_cpu_number_to_vp_number(int cpu_number);
+u64 hv_do_hypercall(u64 control, void *input, void *output);
 
 /**
  * VMBUS_DEVICE - macro used to describe a specific hyperv vmbus device