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1 /*
2 * Copyright (c) 2000,2002-2003,2005 Silicon Graphics, Inc.
3 * All Rights Reserved.
4 *
5 * This program is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU General Public License as
7 * published by the Free Software Foundation.
8 *
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.
13 *
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
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 xfs_attr_list_context;
40
41 typedef int (*attrset_t)(bhv_vnode_t *, char *, void *, size_t, int);
42 typedef int (*attrget_t)(bhv_vnode_t *, char *, void *, size_t, int);
43 typedef int (*attrremove_t)(bhv_vnode_t *, char *, int);
44 typedef int (*attrexists_t)(bhv_vnode_t *);
45 typedef int (*attrcapable_t)(bhv_vnode_t *, 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
65 extern attrnames_t *attr_lookup_namespace(char *, attrnames_t **, int);
66 extern int attr_generic_list(bhv_vnode_t *, 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 (64*1024) /* 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 */
161 int xfs_attr_inactive(struct xfs_inode *dp);
162
163 int xfs_attr_shortform_getvalue(struct xfs_da_args *);
164 int xfs_attr_fetch(struct xfs_inode *, struct xfs_name *, char *, int *, int);
165 int xfs_attr_rmtval_get(struct xfs_da_args *args);
166
167 #endif /* __XFS_ATTR_H__ */