mirror of
https://github.com/torvalds/linux
synced 2024-07-21 10:41:44 +00:00
3325b4d857
The s390_hypfs filesystem is deprecated and shouldn't be used due to its rather odd semantics. It creates a whole directory structure with static file contents so a user can read a consistent state while within that directory. Writing to its update attribute will remove and rebuild nearly the whole filesystem, so that again a user can read a consistent state, even if multiple files need to be read. Given that this wastes a lot of CPU cycles, and involves a lot of code, binary interfaces have been added quite a couple of years ago, which simply pass the binary data to user space, and let user space decode the data. This is the preferred and only way how the data should be retrieved. The assumption is that there are no users of the s390_hypfs filesystem. However instead of just removing the code, and having to revert in case there are actually users, factor the filesystem code out and make it only available via a new config option. This config option is supposed to be disabled. If it turns out there are no complaints the filesystem code can be removed probably in a couple of years. Acked-by: Alexander Gordeev <agordeev@linux.ibm.com> Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
86 lines
2 KiB
C
86 lines
2 KiB
C
/* SPDX-License-Identifier: GPL-2.0 */
|
|
/*
|
|
* Hypervisor filesystem for Linux on s390.
|
|
*
|
|
* Copyright IBM Corp. 2006
|
|
* Author(s): Michael Holzheu <holzheu@de.ibm.com>
|
|
*/
|
|
|
|
#ifndef _HYPFS_H_
|
|
#define _HYPFS_H_
|
|
|
|
#include <linux/fs.h>
|
|
#include <linux/types.h>
|
|
#include <linux/debugfs.h>
|
|
#include <linux/workqueue.h>
|
|
#include <linux/kref.h>
|
|
#include <asm/hypfs.h>
|
|
|
|
#define REG_FILE_MODE 0440
|
|
#define UPDATE_FILE_MODE 0220
|
|
#define DIR_MODE 0550
|
|
|
|
extern struct dentry *hypfs_mkdir(struct dentry *parent, const char *name);
|
|
|
|
extern struct dentry *hypfs_create_u64(struct dentry *dir, const char *name,
|
|
__u64 value);
|
|
|
|
extern struct dentry *hypfs_create_str(struct dentry *dir, const char *name,
|
|
char *string);
|
|
|
|
/* LPAR Hypervisor */
|
|
extern int hypfs_diag_init(void);
|
|
extern void hypfs_diag_exit(void);
|
|
extern int hypfs_diag_create_files(struct dentry *root);
|
|
|
|
/* VM Hypervisor */
|
|
extern int hypfs_vm_init(void);
|
|
extern void hypfs_vm_exit(void);
|
|
extern int hypfs_vm_create_files(struct dentry *root);
|
|
|
|
/* VM diagnose 0c */
|
|
int hypfs_diag0c_init(void);
|
|
void hypfs_diag0c_exit(void);
|
|
|
|
/* Set Partition-Resource Parameter */
|
|
void hypfs_sprp_init(void);
|
|
void hypfs_sprp_exit(void);
|
|
|
|
int __hypfs_fs_init(void);
|
|
|
|
static inline int hypfs_fs_init(void)
|
|
{
|
|
if (IS_ENABLED(CONFIG_S390_HYPFS_FS))
|
|
return __hypfs_fs_init();
|
|
return 0;
|
|
}
|
|
|
|
/* debugfs interface */
|
|
struct hypfs_dbfs_file;
|
|
|
|
struct hypfs_dbfs_data {
|
|
void *buf;
|
|
void *buf_free_ptr;
|
|
size_t size;
|
|
struct hypfs_dbfs_file *dbfs_file;
|
|
};
|
|
|
|
struct hypfs_dbfs_file {
|
|
const char *name;
|
|
int (*data_create)(void **data, void **data_free_ptr,
|
|
size_t *size);
|
|
void (*data_free)(const void *buf_free_ptr);
|
|
long (*unlocked_ioctl) (struct file *, unsigned int,
|
|
unsigned long);
|
|
|
|
/* Private data for hypfs_dbfs.c */
|
|
struct mutex lock;
|
|
struct dentry *dentry;
|
|
};
|
|
|
|
extern void hypfs_dbfs_exit(void);
|
|
extern void hypfs_dbfs_create_file(struct hypfs_dbfs_file *df);
|
|
extern void hypfs_dbfs_remove_file(struct hypfs_dbfs_file *df);
|
|
|
|
#endif /* _HYPFS_H_ */
|