ftdev: let bufffer-specific code handle writes from userspace

This allows us to splice in information into logs from events
that were recorded in userspace.

1 files changed, 4 insertions, 1 deletions

diff --git a/include/litmus/ftdev.h b/include/litmus/ftdev.h
index 348387e9adf9..0b959874dd70 100644
--- a/include/litmus/ftdev.h
+++ b/include/litmus/ftdev.h
@@ -16,7 +16,8 @@ typedef int  (*ftdev_can_open_t)(struct ftdev* dev, unsigned int buf_no);
 /* return 0 on success, otherwise -$REASON */
 typedef int  (*ftdev_alloc_t)(struct ftdev* dev, unsigned int buf_no);
 typedef void (*ftdev_free_t)(struct ftdev* dev, unsigned int buf_no);
-
+/* Let devices handle writes from userspace. No synchronization provided. */
+typedef ssize_t (*ftdev_write_t)(struct ft_buffer* buf, size_t len, const char __user *from);
 
 struct ftdev_event;
 
@@ -27,6 +28,7 @@ struct ftdev_minor {
         /* FIXME: filter for authorized events */
         struct ftdev_event*     events;
         struct device*          device;
+        struct ftdev*           ftdev;
 };
 
 struct ftdev {
@@ -39,6 +41,7 @@ struct ftdev {
         ftdev_alloc_t           alloc;
         ftdev_free_t            free;
         ftdev_can_open_t        can_open;
+        ftdev_write_t           write;
 };
 
 struct ft_buffer* alloc_ft_buffer(unsigned int count, size_t size);