1. 根目录:
2. fs
3. xfs
4. linux-2.6
5. xfs_sysctl.h

/*
 * Copyright (c) 2001-2005 Silicon Graphics, Inc.
 * All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it would be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write the Free Software Foundation,
 * Inc.,  51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 */
#ifndef __XFS_SYSCTL_H__
#define __XFS_SYSCTL_H__

#include <linux/sysctl.h>

/*
 * Tunable xfs parameters
 */

typedef struct xfs_sysctl_val {
	int min;
	int val;
	int max;
} xfs_sysctl_val_t;

typedef struct xfs_param {
	xfs_sysctl_val_t sgid_inherit;	/* Inherit S_ISGID if process' GID is
					 * not a member of parent dir GID. */
	xfs_sysctl_val_t symlink_mode;	/* Link creat mode affected by umask */
	xfs_sysctl_val_t panic_mask;	/* bitmask to cause panic on errors. */
	xfs_sysctl_val_t error_level;	/* Degree of reporting for problems  */
	xfs_sysctl_val_t syncd_timer;	/* Interval between xfssyncd wakeups */
	xfs_sysctl_val_t stats_clear;	/* Reset all XFS statistics to zero. */
	xfs_sysctl_val_t inherit_sync;	/* Inherit the "sync" inode flag. */
	xfs_sysctl_val_t inherit_nodump;/* Inherit the "nodump" inode flag. */
	xfs_sysctl_val_t inherit_noatim;/* Inherit the "noatime" inode flag. */
	xfs_sysctl_val_t xfs_buf_timer;	/* Interval between xfsbufd wakeups. */
	xfs_sysctl_val_t xfs_buf_age;	/* Metadata buffer age before flush. */
	xfs_sysctl_val_t inherit_nosym;	/* Inherit the "nosymlinks" flag. */
	xfs_sysctl_val_t rotorstep;	/* inode32 AG rotoring control knob */
	xfs_sysctl_val_t inherit_nodfrg;/* Inherit the "nodefrag" inode flag. */
	xfs_sysctl_val_t fstrm_timer;	/* Filestream dir-AG assoc'n timeout. */
} xfs_param_t;

/*
 * xfs_error_level:
 *
 * How much error reporting will be done when internal problems are
 * encountered.  These problems normally return an EFSCORRUPTED to their
 * caller, with no other information reported.
 *
 * 0	No error reports
 * 1	Report EFSCORRUPTED errors that will cause a filesystem shutdown
 * 5	Report all EFSCORRUPTED errors (all of the above errors, plus any
 *	additional errors that are known to not cause shutdowns)
 *
 * xfs_panic_mask bit 0x8 turns the error reports into panics
 */

enum {
	/* XFS_REFCACHE_SIZE = 1 */
	/* XFS_REFCACHE_PURGE = 2 */
	/* XFS_RESTRICT_CHOWN = 3 */
	XFS_SGID_INHERIT = 4,
	XFS_SYMLINK_MODE = 5,
	XFS_PANIC_MASK = 6,
	XFS_ERRLEVEL = 7,
	XFS_SYNCD_TIMER = 8,
	/* XFS_PROBE_DMAPI = 9 */
	/* XFS_PROBE_IOOPS = 10 */
	/* XFS_PROBE_QUOTA = 11 */
	XFS_STATS_CLEAR = 12,
	XFS_INHERIT_SYNC = 13,
	XFS_INHERIT_NODUMP = 14,
	XFS_INHERIT_NOATIME = 15,
	XFS_BUF_TIMER = 16,
	XFS_BUF_AGE = 17,
	/* XFS_IO_BYPASS = 18 */
	XFS_INHERIT_NOSYM = 19,
	XFS_ROTORSTEP = 20,
	XFS_INHERIT_NODFRG = 21,
	XFS_FILESTREAM_TIMER = 22,
};

extern xfs_param_t	xfs_params;

#ifdef CONFIG_SYSCTL
extern int xfs_sysctl_register(void);
extern void xfs_sysctl_unregister(void);
#else
# define xfs_sysctl_register()		(0)
# define xfs_sysctl_unregister()	do { } while (0)
#endif /* CONFIG_SYSCTL */

#endif /* __XFS_SYSCTL_H__ */