vmbus: expose debug info for drivers

Allow driver to get debug information about state of the ring.

Signed-off-by: Stephen Hemminger <sthemmin@microsoft.com>
Signed-off-by: K. Y. Srinivasan <kys@microsoft.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 17 insertions, 0 deletions

diff --git a/include/linux/hyperv.h b/include/linux/hyperv.h
index de9b80ff6698..1fa727fe5f93 100644
--- a/include/linux/hyperv.h
+++ b/include/linux/hyperv.h
@@ -491,6 +491,12 @@ struct vmbus_channel_rescind_offer {
         u32 child_relid;
 } __packed;
 
+static inline u32
+hv_ringbuffer_pending_size(const struct hv_ring_buffer_info *rbi)
+{
+        return rbi->ring_buffer->pending_send_sz;
+}
+
 /*
  * Request Offer -- no parameters, SynIC message contains the partition ID
  * Set Snoop -- no parameters, SynIC message contains the partition ID
@@ -1148,6 +1154,17 @@ static inline void *hv_get_drvdata(struct hv_device *dev)
         return dev_get_drvdata(&dev->device);
 }
 
+struct hv_ring_buffer_debug_info {
+        u32 current_interrupt_mask;
+        u32 current_read_index;
+        u32 current_write_index;
+        u32 bytes_avail_toread;
+        u32 bytes_avail_towrite;
+};
+
+void hv_ringbuffer_get_debuginfo(const struct hv_ring_buffer_info *ring_info,
+                            struct hv_ring_buffer_debug_info *debug_info);
+
 /* Vmbus interface */
 #define vmbus_driver_register(driver)   \
         __vmbus_driver_register(driver, THIS_MODULE, KBUILD_MODNAME)