diff options
Diffstat (limited to 'drivers/virtio/virtio_debug.c')
| -rw-r--r-- | drivers/virtio/virtio_debug.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/drivers/virtio/virtio_debug.c b/drivers/virtio/virtio_debug.c new file mode 100644 index 000000000000..95c8fc7705bb --- /dev/null +++ b/drivers/virtio/virtio_debug.c @@ -0,0 +1,114 @@ +// SPDX-License-Identifier: GPL-2.0-or-later + +#include <linux/virtio.h> +#include <linux/virtio_config.h> +#include <linux/debugfs.h> + +static struct dentry *virtio_debugfs_dir; + +static int virtio_debug_device_features_show(struct seq_file *s, void *data) +{ + struct virtio_device *dev = s->private; + u64 device_features; + unsigned int i; + + device_features = dev->config->get_features(dev); + for (i = 0; i < BITS_PER_LONG_LONG; i++) { + if (device_features & (1ULL << i)) + seq_printf(s, "%u\n", i); + } + return 0; +} +DEFINE_SHOW_ATTRIBUTE(virtio_debug_device_features); + +static int virtio_debug_filter_features_show(struct seq_file *s, void *data) +{ + struct virtio_device *dev = s->private; + unsigned int i; + + for (i = 0; i < BITS_PER_LONG_LONG; i++) { + if (dev->debugfs_filter_features & (1ULL << i)) + seq_printf(s, "%u\n", i); + } + return 0; +} +DEFINE_SHOW_ATTRIBUTE(virtio_debug_filter_features); + +static int virtio_debug_filter_features_clear(void *data, u64 val) +{ + struct virtio_device *dev = data; + + if (val == 1) + dev->debugfs_filter_features = 0; + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_features_clear_fops, NULL, + virtio_debug_filter_features_clear, "%llu\n"); + +static int virtio_debug_filter_feature_add(void *data, u64 val) +{ + struct virtio_device *dev = data; + + if (val >= BITS_PER_LONG_LONG) + return -EINVAL; + dev->debugfs_filter_features |= BIT_ULL_MASK(val); + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_feature_add_fops, NULL, + virtio_debug_filter_feature_add, "%llu\n"); + +static int virtio_debug_filter_feature_del(void *data, u64 val) +{ + struct virtio_device *dev = data; + + if (val >= BITS_PER_LONG_LONG) + return -EINVAL; + dev->debugfs_filter_features &= ~BIT_ULL_MASK(val); + return 0; +} + +DEFINE_DEBUGFS_ATTRIBUTE(virtio_debug_filter_feature_del_fops, NULL, + virtio_debug_filter_feature_del, "%llu\n"); + +void virtio_debug_device_init(struct virtio_device *dev) +{ + dev->debugfs_dir = debugfs_create_dir(dev_name(&dev->dev), + virtio_debugfs_dir); + debugfs_create_file("device_features", 0400, dev->debugfs_dir, dev, + &virtio_debug_device_features_fops); + debugfs_create_file("filter_features", 0400, dev->debugfs_dir, dev, + &virtio_debug_filter_features_fops); + debugfs_create_file("filter_features_clear", 0200, dev->debugfs_dir, dev, + &virtio_debug_filter_features_clear_fops); + debugfs_create_file("filter_feature_add", 0200, dev->debugfs_dir, dev, + &virtio_debug_filter_feature_add_fops); + debugfs_create_file("filter_feature_del", 0200, dev->debugfs_dir, dev, + &virtio_debug_filter_feature_del_fops); +} +EXPORT_SYMBOL_GPL(virtio_debug_device_init); + +void virtio_debug_device_filter_features(struct virtio_device *dev) +{ + dev->features &= ~dev->debugfs_filter_features; +} +EXPORT_SYMBOL_GPL(virtio_debug_device_filter_features); + +void virtio_debug_device_exit(struct virtio_device *dev) +{ + debugfs_remove_recursive(dev->debugfs_dir); +} +EXPORT_SYMBOL_GPL(virtio_debug_device_exit); + +void virtio_debug_init(void) +{ + virtio_debugfs_dir = debugfs_create_dir("virtio", NULL); +} +EXPORT_SYMBOL_GPL(virtio_debug_init); + +void virtio_debug_exit(void) +{ + debugfs_remove_recursive(virtio_debugfs_dir); +} +EXPORT_SYMBOL_GPL(virtio_debug_exit); |