[PATCH v3 2/7] vfio: platform: add capability to register a reset function

Eric Auger
2015-10-23T12:40:41Z

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
two new functions, vfio_platform_register/unregister_reset. Those are
not yet used in this patch.

Signed-off-by: Eric Auger <eric.auger@linaro.org>

---

v2 -> v3:
- use goto out to have a single mutex_unlock
- implement vfio_platform_register_reset as a macro (suggested by Arnd)
- move reset_node struct declaration back to vfio_platform_private.h
- vfio_platform_unregister_reset does not return any value anymore

v1 -> v2:
- reset_list becomes static
- vfio_platform_register/unregister_reset take a const char * as compat
- fix node leak
- add reset_lock to protect the reset list manipulation
- move vfio_platform_reset_node declaration in vfio_platform_common.c
---
drivers/vfio/platform/vfio_platform_common.c | 26 ++++++++++++++++++++++++++
drivers/vfio/platform/vfio_platform_private.h | 20 ++++++++++++++++++++
2 files changed, 46 insertions(+)

diff --git a/drivers/vfio/platform/vfio_platform_common.c b/drivers/vfio/platform/vfio_platform_common.c
index 184e9d2..8eccd30 100644
--- 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 +579,31 @@ struct vfio_platform_device *vfio_platform_remove_common(struct device *dev)
}
EXPORT_SYMBOL_GPL(vfio_platform_remove_common);

+int __vfio_platform_register_reset(struct vfio_platform_reset_node *node)
+{
+ mutex_lock(&driver_lock);
+ list_add(&node->link, &reset_list);
+ mutex_unlock(&driver_lock);
+ return 0;
+}
+EXPORT_SYMBOL_GPL(__vfio_platform_register_reset);
+
+void vfio_platform_unregister_reset(const char *compat)
+{
+ 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)) {
+ 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 7128690..277521a 100644
--- 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 int __vfio_platform_register_reset(struct vfio_platform_reset_node *n);
+extern void vfio_platform_unregister_reset(const char *compat);
+
+#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 */
--
1.9.1