binderfs: add support for feature files
Provide userspace with a mechanism to discover features supported by the binder driver to refrain from using any unsupported ones in the first place. Starting with "oneway_spam_detection" only new features are to be listed under binderfs and all previous ones are assumed to be supported. Assuming an instance of binderfs has been mounted at /dev/binderfs, binder feature files can be found under /dev/binderfs/features/. Usage example: $ mkdir /dev/binderfs $ mount -t binder binder /dev/binderfs $ cat /dev/binderfs/features/oneway_spam_detection 1 Acked-by: Christian Brauner <christian.brauner@ubuntu.com> Signed-off-by: Carlos Llamas <cmllamas@google.com> Link: https://lore.kernel.org/r/20210715031805.1725878-1-cmllamas@google.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
ec7b5eda8a
commit
fc470abf54
|
@ -58,6 +58,10 @@ enum binderfs_stats_mode {
|
|||
binderfs_stats_mode_global,
|
||||
};
|
||||
|
||||
struct binder_features {
|
||||
bool oneway_spam_detection;
|
||||
};
|
||||
|
||||
static const struct constant_table binderfs_param_stats[] = {
|
||||
{ "global", binderfs_stats_mode_global },
|
||||
{}
|
||||
|
@ -69,6 +73,10 @@ static const struct fs_parameter_spec binderfs_fs_parameters[] = {
|
|||
{}
|
||||
};
|
||||
|
||||
static struct binder_features binder_features = {
|
||||
.oneway_spam_detection = true,
|
||||
};
|
||||
|
||||
static inline struct binderfs_info *BINDERFS_SB(const struct super_block *sb)
|
||||
{
|
||||
return sb->s_fs_info;
|
||||
|
@ -583,6 +591,33 @@ out:
|
|||
return dentry;
|
||||
}
|
||||
|
||||
static int binder_features_show(struct seq_file *m, void *unused)
|
||||
{
|
||||
bool *feature = m->private;
|
||||
|
||||
seq_printf(m, "%d\n", *feature);
|
||||
|
||||
return 0;
|
||||
}
|
||||
DEFINE_SHOW_ATTRIBUTE(binder_features);
|
||||
|
||||
static int init_binder_features(struct super_block *sb)
|
||||
{
|
||||
struct dentry *dentry, *dir;
|
||||
|
||||
dir = binderfs_create_dir(sb->s_root, "features");
|
||||
if (IS_ERR(dir))
|
||||
return PTR_ERR(dir);
|
||||
|
||||
dentry = binderfs_create_file(dir, "oneway_spam_detection",
|
||||
&binder_features_fops,
|
||||
&binder_features.oneway_spam_detection);
|
||||
if (IS_ERR(dentry))
|
||||
return PTR_ERR(dentry);
|
||||
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int init_binder_logs(struct super_block *sb)
|
||||
{
|
||||
struct dentry *binder_logs_root_dir, *dentry, *proc_log_dir;
|
||||
|
@ -723,6 +758,10 @@ static int binderfs_fill_super(struct super_block *sb, struct fs_context *fc)
|
|||
name++;
|
||||
}
|
||||
|
||||
ret = init_binder_features(sb);
|
||||
if (ret)
|
||||
return ret;
|
||||
|
||||
if (info->mount_opts.stats_mode == binderfs_stats_mode_global)
|
||||
return init_binder_logs(sb);
|
||||
|
||||
|
|
Loading…
Reference in New Issue