[linux.git] / fs / xfs / xfs_attr.h

/*
 * Copyright (c) 2000,2002-2003,2005 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_ATTR_H__
#define	__XFS_ATTR_H__

/*
 * xfs_attr.h
 *
 * Large attribute lists are structured around Btrees where all the data
 * elements are in the leaf nodes.  Attribute names are hashed into an int,
 * then that int is used as the index into the Btree.  Since the hashval
 * of an attribute name may not be unique, we may have duplicate keys.
 * The internal links in the Btree are logical block offsets into the file.
 *
 * Small attribute lists use a different format and are packed as tightly
 * as possible so as to fit into the literal area of the inode.
 */

/*========================================================================
 * External interfaces
 *========================================================================*/

struct cred;
struct vnode;

typedef int (*attrset_t)(struct vnode *, char *, void *, size_t, int);
typedef int (*attrget_t)(struct vnode *, char *, void *, size_t, int);
typedef int (*attrremove_t)(struct vnode *, char *, int);
typedef int (*attrexists_t)(struct vnode *);
typedef int (*attrcapable_t)(struct vnode *, struct cred *);

typedef struct attrnames {
	char *		attr_name;
	unsigned int	attr_namelen;
	unsigned int	attr_flag;
	attrget_t	attr_get;
	attrset_t	attr_set;
	attrremove_t	attr_remove;
	attrexists_t	attr_exists;
	attrcapable_t	attr_capable;
} attrnames_t;

#define ATTR_NAMECOUNT	4
extern struct attrnames attr_user;
extern struct attrnames attr_secure;
extern struct attrnames attr_system;
extern struct attrnames attr_trusted;
extern struct attrnames *attr_namespaces[ATTR_NAMECOUNT];

extern attrnames_t *attr_lookup_namespace(char *, attrnames_t **, int);
extern int attr_generic_list(struct vnode *, void *, size_t, int, ssize_t *);

#define ATTR_DONTFOLLOW	0x0001	/* -- unused, from IRIX -- */
#define ATTR_ROOT	0x0002	/* use attrs in root (trusted) namespace */
#define ATTR_TRUST	0x0004	/* -- unused, from IRIX -- */
#define ATTR_SECURE	0x0008	/* use attrs in security namespace */
#define ATTR_CREATE	0x0010	/* pure create: fail if attr already exists */
#define ATTR_REPLACE	0x0020	/* pure set: fail if attr does not exist */
#define ATTR_SYSTEM	0x0100	/* use attrs in system (pseudo) namespace */

#define ATTR_KERNACCESS	0x0400	/* [kernel] iaccess, inode held io-locked */
#define ATTR_KERNOTIME	0x1000	/* [kernel] don't update inode timestamps */
#define ATTR_KERNOVAL	0x2000	/* [kernel] get attr size only, not value */
#define ATTR_KERNAMELS	0x4000	/* [kernel] list attr names (simple list) */

#define ATTR_KERNORMALS	0x0800	/* [kernel] normal attr list: user+secure */
#define ATTR_KERNROOTLS	0x8000	/* [kernel] include root in the attr list */
#define ATTR_KERNFULLS	(ATTR_KERNORMALS|ATTR_KERNROOTLS)

/*
 * The maximum size (into the kernel or returned from the kernel) of an
 * attribute value or the buffer used for an attr_list() call.  Larger
 * sizes will result in an ERANGE return code.
 */
#define	ATTR_MAX_VALUELEN	(64*1024)	/* max length of a value */

/*
 * Define how lists of attribute names are returned to the user from
 * the attr_list() call.  A large, 32bit aligned, buffer is passed in
 * along with its size.  We put an array of offsets at the top that each
 * reference an attrlist_ent_t and pack the attrlist_ent_t's at the bottom.
 */
typedef struct attrlist {
	__s32	al_count;	/* number of entries in attrlist */
	__s32	al_more;	/* T/F: more attrs (do call again) */
	__s32	al_offset[1];	/* byte offsets of attrs [var-sized] */
} attrlist_t;

/*
 * Show the interesting info about one attribute.  This is what the
 * al_offset[i] entry points to.
 */
typedef struct attrlist_ent {	/* data from attr_list() */
	__u32	a_valuelen;	/* number bytes in value of attr */
	char	a_name[1];	/* attr name (NULL terminated) */
} attrlist_ent_t;

/*
 * Given a pointer to the (char*) buffer containing the attr_list() result,
 * and an index, return a pointer to the indicated attribute in the buffer.
 */
#define	ATTR_ENTRY(buffer, index)		\
	((attrlist_ent_t *)			\
	 &((char *)buffer)[ ((attrlist_t *)(buffer))->al_offset[index] ])

/*
 * Multi-attribute operation vector.
 */
typedef struct attr_multiop {
	int	am_opcode;	/* operation to perform (ATTR_OP_GET, etc.) */
	int	am_error;	/* [out arg] result of this sub-op (an errno) */
	char	*am_attrname;	/* attribute name to work with */
	char	*am_attrvalue;	/* [in/out arg] attribute value (raw bytes) */
	int	am_length;	/* [in/out arg] length of value */
	int	am_flags;	/* bitwise OR of attr API flags defined above */
} attr_multiop_t;

#define ATTR_OP_GET	1	/* return the indicated attr's value */
#define ATTR_OP_SET	2	/* set/create the indicated attr/value pair */
#define ATTR_OP_REMOVE	3	/* remove the indicated attr */

/*
 * Kernel-internal version of the attrlist cursor.
 */
typedef struct attrlist_cursor_kern {
	__u32	hashval;	/* hash value of next entry to add */
	__u32	blkno;		/* block containing entry (suggestion) */
	__u32	offset;		/* offset in list of equal-hashvals */
	__u16	pad1;		/* padding to match user-level */
	__u8	pad2;		/* padding to match user-level */
	__u8	initted;	/* T/F: cursor has been initialized */
} attrlist_cursor_kern_t;


/*========================================================================
 * Function prototypes for the kernel.
 *========================================================================*/

struct xfs_inode;
struct attrlist_cursor_kern;
struct xfs_da_args;

/*
 * Overall external interface routines.
 */
int xfs_attr_get(bhv_desc_t *, const char *, char *, int *, int, struct cred *);
int xfs_attr_set(bhv_desc_t *, const char *, char *, int, int, struct cred *);
int xfs_attr_remove(bhv_desc_t *, const char *, int, struct cred *);
int xfs_attr_list(bhv_desc_t *, char *, int, int,
			 struct attrlist_cursor_kern *, struct cred *);
int xfs_attr_inactive(struct xfs_inode *dp);

int xfs_attr_shortform_getvalue(struct xfs_da_args *);
int xfs_attr_fetch(struct xfs_inode *, const char *, int,
			char *, int *, int, struct cred *);

#endif	/* __XFS_ATTR_H__ */
Commit	Line	Data
1da177e4	1	/*
7b718769 NS	2	* Copyright (c) 2000,2002-2003,2005 Silicon Graphics, Inc.
7b718769 NS	3	* All Rights Reserved.
1da177e4	4	*
7b718769 NS	5	* This program is free software; you can redistribute it and/or
7b718769 NS	6	* modify it under the terms of the GNU General Public License as
1da177e4 LT	7	* published by the Free Software Foundation.
1da177e4 LT	8	*
7b718769 NS	9	* This program is distributed in the hope that it would be useful,
	10	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	11	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	12	* GNU General Public License for more details.
1da177e4	13	*
7b718769 NS	14	* You should have received a copy of the GNU General Public License
	15	* along with this program; if not, write the Free Software Foundation,
	16	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
1da177e4 LT	17	*/
	18	#ifndef __XFS_ATTR_H__
	19	#define __XFS_ATTR_H__
	20
	21	/*
	22	* xfs_attr.h
	23	*
	24	* Large attribute lists are structured around Btrees where all the data
	25	* elements are in the leaf nodes. Attribute names are hashed into an int,
	26	* then that int is used as the index into the Btree. Since the hashval
	27	* of an attribute name may not be unique, we may have duplicate keys.
	28	* The internal links in the Btree are logical block offsets into the file.
	29	*
	30	* Small attribute lists use a different format and are packed as tightly
	31	* as possible so as to fit into the literal area of the inode.
	32	*/
	33
	34	/*========================================================================
	35	* External interfaces
	36	========================================================================/
	37
	38	struct cred;
	39	struct vnode;
	40
	41	typedef int (attrset_t)(struct vnode , char , void , size_t, int);
	42	typedef int (attrget_t)(struct vnode , char , void , size_t, int);
	43	typedef int (attrremove_t)(struct vnode , char *, int);
	44	typedef int (attrexists_t)(struct vnode );
	45	typedef int (attrcapable_t)(struct vnode , struct cred *);
	46
	47	typedef struct attrnames {
	48	char * attr_name;
	49	unsigned int attr_namelen;
	50	unsigned int attr_flag;
	51	attrget_t attr_get;
	52	attrset_t attr_set;
	53	attrremove_t attr_remove;
	54	attrexists_t attr_exists;
	55	attrcapable_t attr_capable;
	56	} attrnames_t;
	57
	58	#define ATTR_NAMECOUNT 4
	59	extern struct attrnames attr_user;
	60	extern struct attrnames attr_secure;
	61	extern struct attrnames attr_system;
	62	extern struct attrnames attr_trusted;
	63	extern struct attrnames *attr_namespaces[ATTR_NAMECOUNT];
	64
1da177e4 LT	65	extern attrnames_t attr_lookup_namespace(char , attrnames_t **, int);
	66	extern int attr_generic_list(struct vnode , void , size_t, int, ssize_t *);
	67
	68	#define ATTR_DONTFOLLOW 0x0001 /* -- unused, from IRIX -- */
	69	#define ATTR_ROOT 0x0002 /* use attrs in root (trusted) namespace */
	70	#define ATTR_TRUST 0x0004 /* -- unused, from IRIX -- */
	71	#define ATTR_SECURE 0x0008 /* use attrs in security namespace */
	72	#define ATTR_CREATE 0x0010 /* pure create: fail if attr already exists */
	73	#define ATTR_REPLACE 0x0020 /* pure set: fail if attr does not exist */
	74	#define ATTR_SYSTEM 0x0100 /* use attrs in system (pseudo) namespace */
	75
	76	#define ATTR_KERNACCESS 0x0400 /* [kernel] iaccess, inode held io-locked */
	77	#define ATTR_KERNOTIME 0x1000 /* [kernel] don't update inode timestamps */
	78	#define ATTR_KERNOVAL 0x2000 /* [kernel] get attr size only, not value */
	79	#define ATTR_KERNAMELS 0x4000 /* [kernel] list attr names (simple list) */
	80
	81	#define ATTR_KERNORMALS 0x0800 /* [kernel] normal attr list: user+secure */
	82	#define ATTR_KERNROOTLS 0x8000 /* [kernel] include root in the attr list */
	83	#define ATTR_KERNFULLS (ATTR_KERNORMALS\|ATTR_KERNROOTLS)
	84
	85	/*
	86	* The maximum size (into the kernel or returned from the kernel) of an
	87	* attribute value or the buffer used for an attr_list() call. Larger
	88	* sizes will result in an ERANGE return code.
	89	*/
	90	#define ATTR_MAX_VALUELEN (641024) / max length of a value */
	91
	92	/*
	93	* Define how lists of attribute names are returned to the user from
	94	* the attr_list() call. A large, 32bit aligned, buffer is passed in
	95	* along with its size. We put an array of offsets at the top that each
	96	* reference an attrlist_ent_t and pack the attrlist_ent_t's at the bottom.
	97	*/
	98	typedef struct attrlist {
	99	__s32 al_count; /* number of entries in attrlist */
	100	__s32 al_more; /* T/F: more attrs (do call again) */
	101	__s32 al_offset[1]; /* byte offsets of attrs [var-sized] */
	102	} attrlist_t;
	103
	104	/*
	105	* Show the interesting info about one attribute. This is what the
	106	* al_offset[i] entry points to.
	107	*/
	108	typedef struct attrlist_ent { /* data from attr_list() */
	109	__u32 a_valuelen; /* number bytes in value of attr */
	110	char a_name[1]; /* attr name (NULL terminated) */
	111	} attrlist_ent_t;
	112
	113	/*
	114	* Given a pointer to the (char*) buffer containing the attr_list() result,
	115	* and an index, return a pointer to the indicated attribute in the buffer.
	116	*/
	117	#define ATTR_ENTRY(buffer, index) \
	118	((attrlist_ent_t *) \
	119	&((char )buffer)[ ((attrlist_t )(buffer))->al_offset[index] ])
	120
	121	/*
	122	* Multi-attribute operation vector.
	123	*/
	124	typedef struct attr_multiop {
	125	int am_opcode; /* operation to perform (ATTR_OP_GET, etc.) */
	126	int am_error; /* [out arg] result of this sub-op (an errno) */
	127	char am_attrname; / attribute name to work with */
	128	char am_attrvalue; / [in/out arg] attribute value (raw bytes) */
129	int am_length; /* [in/out arg] length of value */
130	int am_flags; /* bitwise OR of attr API flags defined above */
131	} attr_multiop_t;
132
133	#define ATTR_OP_GET 1 /* return the indicated attr's value */
134	#define ATTR_OP_SET 2 /* set/create the indicated attr/value pair */
135	#define ATTR_OP_REMOVE 3 /* remove the indicated attr */
136
137	/*
138	* Kernel-internal version of the attrlist cursor.
139	*/
140	typedef struct attrlist_cursor_kern {
141	__u32 hashval; /* hash value of next entry to add */
142	__u32 blkno; /* block containing entry (suggestion) */
143	__u32 offset; /* offset in list of equal-hashvals */
144	__u16 pad1; /* padding to match user-level */
145	__u8 pad2; /* padding to match user-level */
146	__u8 initted; /* T/F: cursor has been initialized */
147	} attrlist_cursor_kern_t;
148
149
150	/*========================================================================
151	* Function prototypes for the kernel.
152	========================================================================/
153
154	struct xfs_inode;
155	struct attrlist_cursor_kern;
156	struct xfs_da_args;
157
158	/*
159	* Overall external interface routines.
160	*/
80cce779 NS	161	int xfs_attr_get(bhv_desc_t , const char , char , int , int, struct cred *);
	162	int xfs_attr_set(bhv_desc_t , const char , char , int, int, struct cred );
	163	int xfs_attr_remove(bhv_desc_t , const char , int, struct cred *);
1da177e4 LT	164	int xfs_attr_list(bhv_desc_t , char , int, int,
	165	struct attrlist_cursor_kern , struct cred );
	166	int xfs_attr_inactive(struct xfs_inode *dp);
	167
1da177e4	168	int xfs_attr_shortform_getvalue(struct xfs_da_args *);
80cce779	169	int xfs_attr_fetch(struct xfs_inode , const char , int,
1da177e4 LT	170	char , int , int, struct cred *);
	171
	172	#endif /* __XFS_ATTR_H__ */