vfio: move eventfd support code for VFIO_PCI to a separate file

The virqfd functionality that is used by VFIO_PCI to implement interrupt
masking and unmasking via an eventfd, is generic enough and can be reused
by another driver. Move it to a separate file in order to allow the code
to be shared.

Signed-off-by: Antonios Motakis <a.motakis@virtualopensystems.com>
Signed-off-by: Baptiste Reynal <b.reynal@virtualopensystems.com>
Reviewed-by: Eric Auger <eric.auger@linaro.org>
Tested-by: Eric Auger <eric.auger@linaro.org>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

1 files changed, 27 insertions, 0 deletions

diff --git a/include/linux/vfio.h b/include/linux/vfio.h
index 2d67b8998fd8..683b5146022e 100644
--- a/include/linux/vfio.h
+++ b/include/linux/vfio.h
@@ -14,6 +14,8 @@
 
 #include <linux/iommu.h>
 #include <linux/mm.h>
+#include <linux/workqueue.h>
+#include <linux/poll.h>
 #include <uapi/linux/vfio.h>
 
 /**
@@ -123,4 +125,29 @@ static inline long vfio_spapr_iommu_eeh_ioctl(struct iommu_group *group,
         return -ENOTTY;
 }
 #endif /* CONFIG_EEH */
+
+/*
+ * IRQfd - generic
+ */
+struct virqfd {
+        void                    *opaque;
+        struct eventfd_ctx      *eventfd;
+        int                     (*handler)(void *, void *);
+        void                    (*thread)(void *, void *);
+        void                    *data;
+        struct work_struct      inject;
+        wait_queue_t            wait;
+        poll_table              pt;
+        struct work_struct      shutdown;
+        struct virqfd           **pvirqfd;
+};
+
+extern int vfio_virqfd_init(void);
+extern void vfio_virqfd_exit(void);
+extern int vfio_virqfd_enable(void *opaque,
+                              int (*handler)(void *, void *),
+                              void (*thread)(void *, void *),
+                              void *data, struct virqfd **pvirqfd, int fd);
+extern void vfio_virqfd_disable(struct virqfd **pvirqfd);
+
 #endif /* VFIO_H */