8c88a47435
In some cases there might be longer-running hardware accesses in debugfs files, or attempts to acquire locks, and we want to still be able to quickly remove the files. Introduce a cancellations API to use inside the debugfs handler functions to be able to cancel such operations on a per-file basis. Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Signed-off-by: Johannes Berg <johannes.berg@intel.com>
63 lines
1.7 KiB
C
63 lines
1.7 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* internal.h - declarations internal to debugfs
|
|
*
|
|
* Copyright (C) 2016 Nicolai Stange <nicstange@gmail.com>
|
|
*/
|
|
|
|
#ifndef _DEBUGFS_INTERNAL_H_
|
|
#define _DEBUGFS_INTERNAL_H_
|
|
#include <linux/lockdep.h>
|
|
#include <linux/list.h>
|
|
|
|
struct file_operations;
|
|
|
|
/* declared over in file.c */
|
|
extern const struct file_operations debugfs_noop_file_operations;
|
|
extern const struct file_operations debugfs_open_proxy_file_operations;
|
|
extern const struct file_operations debugfs_full_proxy_file_operations;
|
|
|
|
struct debugfs_fsdata {
|
|
const struct file_operations *real_fops;
|
|
union {
|
|
/* automount_fn is used when real_fops is NULL */
|
|
debugfs_automount_t automount;
|
|
struct {
|
|
refcount_t active_users;
|
|
struct completion active_users_drained;
|
|
#ifdef CONFIG_LOCKDEP
|
|
struct lockdep_map lockdep_map;
|
|
struct lock_class_key key;
|
|
char *lock_name;
|
|
#endif
|
|
|
|
/* protect cancellations */
|
|
struct mutex cancellations_mtx;
|
|
struct list_head cancellations;
|
|
};
|
|
};
|
|
};
|
|
|
|
/*
|
|
* A dentry's ->d_fsdata either points to the real fops or to a
|
|
* dynamically allocated debugfs_fsdata instance.
|
|
* In order to distinguish between these two cases, a real fops
|
|
* pointer gets its lowest bit set.
|
|
*/
|
|
#define DEBUGFS_FSDATA_IS_REAL_FOPS_BIT BIT(0)
|
|
|
|
/* Access BITS */
|
|
#define DEBUGFS_ALLOW_API BIT(0)
|
|
#define DEBUGFS_ALLOW_MOUNT BIT(1)
|
|
|
|
#ifdef CONFIG_DEBUG_FS_ALLOW_ALL
|
|
#define DEFAULT_DEBUGFS_ALLOW_BITS (DEBUGFS_ALLOW_MOUNT | DEBUGFS_ALLOW_API)
|
|
#endif
|
|
#ifdef CONFIG_DEBUG_FS_DISALLOW_MOUNT
|
|
#define DEFAULT_DEBUGFS_ALLOW_BITS (DEBUGFS_ALLOW_API)
|
|
#endif
|
|
#ifdef CONFIG_DEBUG_FS_ALLOW_NONE
|
|
#define DEFAULT_DEBUGFS_ALLOW_BITS (0)
|
|
#endif
|
|
|
|
#endif /* _DEBUGFS_INTERNAL_H_ */
|