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_vnode; 40 41 typedef int (*attrset_t)(struct xfs_vnode *, char *, void *, size_t, int); 42 typedef int (*attrget_t)(struct xfs_vnode *, char *, void *, size_t, int); 43 typedef int (*attrremove_t)(struct xfs_vnode *, char *, int); 44 typedef int (*attrexists_t)(struct xfs_vnode *); 45 typedef int (*attrcapable_t)(struct xfs_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 65 extern attrnames_t *attr_lookup_namespace(char *, attrnames_t **, int); 66 extern int attr_generic_list(struct xfs_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 (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_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 *); 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); 167 168 int xfs_attr_shortform_getvalue(struct xfs_da_args *); 169 int xfs_attr_fetch(struct xfs_inode *, const char *, int, 170 char *, int *, int, struct cred *); 171 172 #endif /* __XFS_ATTR_H__ */ 173