vfio: platform: add capability to register a reset function

In preparation for subsequent changes in reset function lookup,
lets introduce a dynamic list of reset combos (compat string,
reset module, reset function). The list can be populated/voided with
vfio_platform_register/unregister_reset. Those are not yet used in
this patch.

Signed-off-by: Eric Auger <eric.auger@linaro.org>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>

diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 7f69b852c7e25b025d8d66ec8313673d5ce40105..7decc50ccf30c87cdfcac730d1b0adf465af364f 100644 (file)
--- a/drivers/vfio/platform/vfio_platform_common.c
+++ b/drivers/vfio/platform/vfio_platform_common.c
@@ -27,6 +27,7 @@
 #define DRIVER_AUTHOR   "Antonios Motakis <a.motakis@virtualopensystems.com>"
 #define DRIVER_DESC     "VFIO platform base module"
 
+static LIST_HEAD(reset_list);
 static DEFINE_MUTEX(driver_lock);
 
 static const struct vfio_platform_reset_combo reset_lookup_table[] = {
@@ -578,6 +579,32 @@ struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
 }
 EXPORT_SYMBOL_GPL(vfio_platform_remove_common);
 
+void __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
+{
+       mutex_lock(&driver_lock);
+       list_add(&node->link, &reset_list);
+       mutex_unlock(&driver_lock);
+}
+EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
+
+void vfio_platform_unregister_reset(const char *compat,
+                                   vfio_platform_reset_fn_t fn)
+{
+       struct vfio_platform_reset_node *iter, *temp;
+
+       mutex_lock(&driver_lock);
+       list_for_each_entry_safe(iter, temp, &reset_list, link) {
+               if (!strcmp(iter->compat, compat) && (iter->reset == fn)) {
+                       list_del(&iter->link);
+                       break;
+               }
+       }
+
+       mutex_unlock(&driver_lock);
+
+}
+EXPORT_SYMBOL_GPL(vfio_platform_unregister_reset);
+
 MODULE_VERSION(DRIVER_VERSION);
 MODULE_LICENSE("GPL v2");
 MODULE_AUTHOR(DRIVER_AUTHOR);

diff --git a/drivers/vfio/platform/vfio_platform_private.h b/drivers/vfio/platform/vfio_platform_private.h
index 71286903fb49f7e3096266dc5ac13f9286410010..c563940e0f6b8aa2a88052595d60601a7443cbda 100644 (file)
--- a/drivers/vfio/platform/vfio_platform_private.h
+++ b/drivers/vfio/platform/vfio_platform_private.h
@@ -71,6 +71,15 @@ struct vfio_platform_device {
        int     (*reset)(struct vfio_platform_device *vdev);
 };
 
+typedef int (*vfio_platform_reset_fn_t)(struct vfio_platform_device *vdev);
+
+struct vfio_platform_reset_node {
+       struct list_head link;
+       char *compat;
+       struct module *owner;
+       vfio_platform_reset_fn_t reset;
+};
+
 struct vfio_platform_reset_combo {
        const char *compat;
        const char *reset_function_name;
@@ -90,4 +99,15 @@ extern int vfio_platform_set_irqs_ioctl(struct vfio_platform_device *vdev,
                                        unsigned start, unsigned count,
                                        void *data);
 
+extern void __vfio_platform_register_reset(struct vfio_platform_reset_node *n);
+extern void vfio_platform_unregister_reset(const char *compat,
+                                          vfio_platform_reset_fn_t fn);
+#define vfio_platform_register_reset(__compat, __reset)                \
+static struct vfio_platform_reset_node __reset ## _node = {    \
+       .owner = THIS_MODULE,                                   \
+       .compat = __compat,                                     \
+       .reset = __reset,                                       \
+};                                                             \
+__vfio_platform_register_reset(&__reset ## _node)
+
 #endif /* VFIO_PLATFORM_PRIVATE_H */