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Diffstat (limited to 'drivers/dma/idxd/compat.c')
-rw-r--r--drivers/dma/idxd/compat.c107
1 files changed, 107 insertions, 0 deletions
diff --git a/drivers/dma/idxd/compat.c b/drivers/dma/idxd/compat.c
new file mode 100644
index 0000000000..5fd38d1b9d
--- /dev/null
+++ b/drivers/dma/idxd/compat.c
@@ -0,0 +1,107 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright(c) 2021 Intel Corporation. All rights rsvd. */
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/device.h>
+#include <linux/device/bus.h>
+#include "idxd.h"
+
+extern int device_driver_attach(struct device_driver *drv, struct device *dev);
+extern void device_driver_detach(struct device *dev);
+
+#define DRIVER_ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store) \
+ struct driver_attribute driver_attr_##_name = \
+ __ATTR_IGNORE_LOCKDEP(_name, _mode, _show, _store)
+
+static ssize_t unbind_store(struct device_driver *drv, const char *buf, size_t count)
+{
+ const struct bus_type *bus = drv->bus;
+ struct device *dev;
+ int rc = -ENODEV;
+
+ dev = bus_find_device_by_name(bus, NULL, buf);
+ if (dev && dev->driver) {
+ device_driver_detach(dev);
+ rc = count;
+ }
+
+ return rc;
+}
+static DRIVER_ATTR_IGNORE_LOCKDEP(unbind, 0200, NULL, unbind_store);
+
+static ssize_t bind_store(struct device_driver *drv, const char *buf, size_t count)
+{
+ const struct bus_type *bus = drv->bus;
+ struct device *dev;
+ struct device_driver *alt_drv = NULL;
+ int rc = -ENODEV;
+ struct idxd_dev *idxd_dev;
+
+ dev = bus_find_device_by_name(bus, NULL, buf);
+ if (!dev || dev->driver || drv != &dsa_drv.drv)
+ return -ENODEV;
+
+ idxd_dev = confdev_to_idxd_dev(dev);
+ if (is_idxd_dev(idxd_dev)) {
+ alt_drv = driver_find("idxd", bus);
+ } else if (is_idxd_wq_dev(idxd_dev)) {
+ struct idxd_wq *wq = confdev_to_wq(dev);
+
+ if (is_idxd_wq_kernel(wq))
+ alt_drv = driver_find("dmaengine", bus);
+ else if (is_idxd_wq_user(wq))
+ alt_drv = driver_find("user", bus);
+ }
+ if (!alt_drv)
+ return -ENODEV;
+
+ rc = device_driver_attach(alt_drv, dev);
+ if (rc < 0)
+ return rc;
+
+ return count;
+}
+static DRIVER_ATTR_IGNORE_LOCKDEP(bind, 0200, NULL, bind_store);
+
+static struct attribute *dsa_drv_compat_attrs[] = {
+ &driver_attr_bind.attr,
+ &driver_attr_unbind.attr,
+ NULL,
+};
+
+static const struct attribute_group dsa_drv_compat_attr_group = {
+ .attrs = dsa_drv_compat_attrs,
+};
+
+static const struct attribute_group *dsa_drv_compat_groups[] = {
+ &dsa_drv_compat_attr_group,
+ NULL,
+};
+
+static int idxd_dsa_drv_probe(struct idxd_dev *idxd_dev)
+{
+ return -ENODEV;
+}
+
+static void idxd_dsa_drv_remove(struct idxd_dev *idxd_dev)
+{
+}
+
+static enum idxd_dev_type dev_types[] = {
+ IDXD_DEV_NONE,
+};
+
+struct idxd_device_driver dsa_drv = {
+ .name = "dsa",
+ .probe = idxd_dsa_drv_probe,
+ .remove = idxd_dsa_drv_remove,
+ .type = dev_types,
+ .drv = {
+ .suppress_bind_attrs = true,
+ .groups = dsa_drv_compat_groups,
+ },
+};
+
+module_idxd_driver(dsa_drv);
+MODULE_IMPORT_NS(IDXD);