virtio_debug.c

  1// SPDX-License-Identifier: GPL-2.0-or-later
  2
  3#include <linux/virtio.h>
  4#include <linux/virtio_config.h>
  5#include <linux/debugfs.h>
  6
  7static struct dentry *virtio_debugfs_dir;
  8
  9static int virtio_debug_device_features_show(struct seq_file *s, void *data)
 10{
 11	u64 device_features[VIRTIO_FEATURES_U64S];
 12	struct virtio_device *dev = s->private;
 13	unsigned int i;
 14
 15	virtio_get_features(dev, device_features);
 16	for (i = 0; i < VIRTIO_FEATURES_BITS; i++) {
 17		if (virtio_features_test_bit(device_features, i))
 18			seq_printf(s, "%u\n", i);
 19	}
 20	return 0;
 21}
 22DEFINE_SHOW_ATTRIBUTE(virtio_debug_device_features);
 23
 24static int virtio_debug_filter_features_show(struct seq_file *s, void *data)
 25{
 26	struct virtio_device *dev = s->private;
 27	unsigned int i;
 28
 29	for (i = 0; i < VIRTIO_FEATURES_BITS; i++) {
 30		if (virtio_features_test_bit(dev->debugfs_filter_features, i))
 31			seq_printf(s, "%u\n", i);
 32	}
 33	return 0;
 34}
 35DEFINE_SHOW_ATTRIBUTE(virtio_debug_filter_features);
 36
 37static int virtio_debug_filter_features_clear(void *data, u64 val)
 38{
 39	struct virtio_device *dev = data;
 40
 41	if (val == 1)
 42		virtio_features_zero(dev->debugfs_filter_features);
 43	return 0;
 44}
 45
 46DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_features_clear_fops, NULL,
 47			 virtio_debug_filter_features_clear, "%llu\n");
 48
 49static int virtio_debug_filter_feature_add(void *data, u64 val)
 50{
 51	struct virtio_device *dev = data;
 52
 53	if (val >= VIRTIO_FEATURES_BITS)
 54		return -EINVAL;
 55
 56	virtio_features_set_bit(dev->debugfs_filter_features, val);
 57	return 0;
 58}
 59
 60DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_feature_add_fops, NULL,
 61			 virtio_debug_filter_feature_add, "%llu\n");
 62
 63static int virtio_debug_filter_feature_del(void *data, u64 val)
 64{
 65	struct virtio_device *dev = data;
 66
 67	if (val >= VIRTIO_FEATURES_BITS)
 68		return -EINVAL;
 69
 70	virtio_features_clear_bit(dev->debugfs_filter_features, val);
 71	return 0;
 72}
 73
 74DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_feature_del_fops, NULL,
 75			 virtio_debug_filter_feature_del, "%llu\n");
 76
 77void virtio_debug_device_init(struct virtio_device *dev)
 78{
 79	dev->debugfs_dir = debugfs_create_dir(dev_name(&dev->dev),
 80					      virtio_debugfs_dir);
 81	debugfs_create_file("device_features", 0400, dev->debugfs_dir, dev,
 82			    &virtio_debug_device_features_fops);
 83	debugfs_create_file("filter_features", 0400, dev->debugfs_dir, dev,
 84			    &virtio_debug_filter_features_fops);
 85	debugfs_create_file("filter_features_clear", 0200, dev->debugfs_dir, dev,
 86			    &virtio_debug_filter_features_clear_fops);
 87	debugfs_create_file("filter_feature_add", 0200, dev->debugfs_dir, dev,
 88			    &virtio_debug_filter_feature_add_fops);
 89	debugfs_create_file("filter_feature_del", 0200, dev->debugfs_dir, dev,
 90			    &virtio_debug_filter_feature_del_fops);
 91}
 92EXPORT_SYMBOL_GPL(virtio_debug_device_init);
 93
 94void virtio_debug_device_filter_features(struct virtio_device *dev)
 95{
 96	virtio_features_andnot(dev->features_array, dev->features_array,
 97			       dev->debugfs_filter_features);
 98}
 99EXPORT_SYMBOL_GPL(virtio_debug_device_filter_features);
100
101void virtio_debug_device_exit(struct virtio_device *dev)
102{
103	debugfs_remove_recursive(dev->debugfs_dir);
104}
105EXPORT_SYMBOL_GPL(virtio_debug_device_exit);
106
107void virtio_debug_init(void)
108{
109	virtio_debugfs_dir = debugfs_create_dir("virtio", NULL);
110}
111EXPORT_SYMBOL_GPL(virtio_debug_init);
112
113void virtio_debug_exit(void)
114{
115	debugfs_remove_recursive(virtio_debugfs_dir);
116}
117EXPORT_SYMBOL_GPL(virtio_debug_exit);