1 /*
2  * Copyright (c) 2000-2001 Silicon Graphics, Inc.  All Rights Reserved.
3  *
4  * This program is free software; you can redistribute it and/or modify it
5  * under the terms of version 2 of the GNU General Public License as
6  * published by the Free Software Foundation.
7  *
8  * This program is distributed in the hope that it would be useful, but
9  * WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
11  *
12  * Further, this software is distributed without any warranty that it is
13  * free of the rightful claim of any third person regarding infringement
14  * or the like.  Any license provided herein, whether implied or
15  * otherwise, applies only to this software file.  Patent licenses, if
16  * any, provided herein do not apply to combinations of this program with
17  * other software, or any other product whatsoever.
18  *
19  * You should have received a copy of the GNU General Public License along
20  * with this program; if not, write the Free Software Foundation, Inc., 59
21  * Temple Place - Suite 330, Boston MA 02111-1307, USA.
22  *
23  * Contact information: Silicon Graphics, Inc., 1600 Amphitheatre Pkwy,
24  * Mountain View, CA  94043, or:
25  *
26  * http://www.sgi.com
27  *
28  * For further information regarding this notice, see:
29  *
30  * http://oss.sgi.com/projects/GenInfo/SGIGPLNoticeExplan/
31  */
32 #ifndef __XFS_DIR2_SF_H__
33 #define	__XFS_DIR2_SF_H__
34 
35 /*
36  * Directory layout when stored internal to an inode.
37  *
38  * Small directories are packed as tightly as possible so as to
39  * fit into the literal area of the inode.
40  */
41 
42 struct uio;
43 struct xfs_dabuf;
44 struct xfs_da_args;
45 struct xfs_dir2_block;
46 struct xfs_inode;
47 struct xfs_mount;
48 struct xfs_trans;
49 
50 /*
51  * Maximum size of a shortform directory.
52  */
53 #define	XFS_DIR2_SF_MAX_SIZE	\
54 	(XFS_DINODE_MAX_SIZE - (uint)sizeof(xfs_dinode_core_t) - \
55 	 (uint)sizeof(xfs_agino_t))
56 
57 /*
58  * Inode number stored as 8 8-bit values.
59  */
60 typedef	struct { __uint8_t i[8]; } xfs_dir2_ino8_t;
61 
62 #define	XFS_DIR2_SF_GET_INO8_ARCH(di,arch)	\
63 	(xfs_ino_t)(DIRINO_GET_ARCH(&di,arch))
64 #define	XFS_DIR2_SF_GET_INO8(di)	        \
65 	XFS_DIR2_SF_GET_INO8_ARCH(di,ARCH_NOCONVERT)
66 
67 /*
68  * Inode number stored as 4 8-bit values.
69  * Works a lot of the time, when all the inode numbers in a directory
70  * fit in 32 bits.
71  */
72 typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t;
73 #define	XFS_DIR2_SF_GET_INO4_ARCH(di,arch)	\
74 	(xfs_ino_t)(DIRINO4_GET_ARCH(&di,arch))
75 #define	XFS_DIR2_SF_GET_INO4(di)	        \
76 	XFS_DIR2_SF_GET_INO4_ARCH(di,ARCH_NOCONVERT)
77 
78 typedef union {
79 	xfs_dir2_ino8_t	i8;
80 	xfs_dir2_ino4_t	i4;
81 } xfs_dir2_inou_t;
82 #define	XFS_DIR2_MAX_SHORT_INUM	((xfs_ino_t)0xffffffffULL)
83 
84 /*
85  * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t.
86  * Only need 16 bits, this is the byte offset into the single block form.
87  */
88 typedef struct { __uint8_t i[2]; } xfs_dir2_sf_off_t;
89 
90 /*
91  * The parent directory has a dedicated field, and the self-pointer must
92  * be calculated on the fly.
93  *
94  * Entries are packed toward the top as tightly as possible.  The header
95  * and the elements must be memcpy'd out into a work area to get correct
96  * alignment for the inode number fields.
97  */
98 typedef struct xfs_dir2_sf_hdr {
99 	__uint8_t		count;		/* count of entries */
100 	__uint8_t		i8count;	/* count of 8-byte inode #s */
101 	xfs_dir2_inou_t		parent;		/* parent dir inode number */
102 } xfs_dir2_sf_hdr_t;
103 
104 typedef struct xfs_dir2_sf_entry {
105 	__uint8_t		namelen;	/* actual name length */
106 	xfs_dir2_sf_off_t	offset;		/* saved offset */
107 	__uint8_t		name[1];	/* name, variable size */
108 	xfs_dir2_inou_t		inumber;	/* inode number, var. offset */
109 } xfs_dir2_sf_entry_t;
110 
111 typedef struct xfs_dir2_sf {
112 	xfs_dir2_sf_hdr_t	hdr;		/* shortform header */
113 	xfs_dir2_sf_entry_t	list[1];	/* shortform entries */
114 } xfs_dir2_sf_t;
115 
116 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_HDR_SIZE)
117 int xfs_dir2_sf_hdr_size(int i8count);
118 #define	XFS_DIR2_SF_HDR_SIZE(i8count)	xfs_dir2_sf_hdr_size(i8count)
119 #else
120 #define	XFS_DIR2_SF_HDR_SIZE(i8count)	\
121 	((uint)sizeof(xfs_dir2_sf_hdr_t) - \
122 	 ((i8count) == 0) * \
123 	 ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
124 #endif
125 
126 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_INUMBERP)
127 xfs_dir2_inou_t *xfs_dir2_sf_inumberp(xfs_dir2_sf_entry_t *sfep);
128 #define	XFS_DIR2_SF_INUMBERP(sfep)	xfs_dir2_sf_inumberp(sfep)
129 #else
130 #define	XFS_DIR2_SF_INUMBERP(sfep)	\
131 	((xfs_dir2_inou_t *)&(sfep)->name[(sfep)->namelen])
132 #endif
133 
134 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_GET_INUMBER)
135 xfs_intino_t xfs_dir2_sf_get_inumber_arch(xfs_dir2_sf_t *sfp, xfs_dir2_inou_t *from,
136 					    xfs_arch_t arch);
137 #define	XFS_DIR2_SF_GET_INUMBER_ARCH(sfp, from, arch)	\
138 	xfs_dir2_sf_get_inumber_arch(sfp, from, arch)
139 
140 #else
141 #define	XFS_DIR2_SF_GET_INUMBER_ARCH(sfp, from, arch)	\
142 	((sfp)->hdr.i8count == 0 ? \
143 		(xfs_intino_t)XFS_DIR2_SF_GET_INO4_ARCH(*(from), arch) : \
144 		(xfs_intino_t)XFS_DIR2_SF_GET_INO8_ARCH(*(from), arch))
145 #endif
146 
147 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_PUT_INUMBER)
148 void xfs_dir2_sf_put_inumber_arch(xfs_dir2_sf_t *sfp, xfs_ino_t *from,
149 				     xfs_dir2_inou_t *to, xfs_arch_t arch);
150 #define	XFS_DIR2_SF_PUT_INUMBER_ARCH(sfp,from,to,arch)	\
151 	xfs_dir2_sf_put_inumber_arch(sfp,from,to,arch)
152 #else
153 #define	XFS_DIR2_SF_PUT_INUMBER_ARCH(sfp,from,to,arch)	\
154 	if ((sfp)->hdr.i8count == 0) { \
155 	    DIRINO4_COPY_ARCH(from,to,arch); \
156 	} else { \
157 	    DIRINO_COPY_ARCH(from,to,arch); \
158 	}
159 #endif
160 
161 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_GET_OFFSET)
162 xfs_dir2_data_aoff_t xfs_dir2_sf_get_offset_arch(xfs_dir2_sf_entry_t *sfep,
163 						    xfs_arch_t arch);
164 xfs_dir2_data_aoff_t xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep);
165 #define	XFS_DIR2_SF_GET_OFFSET_ARCH(sfep,arch)	\
166 	xfs_dir2_sf_get_offset_arch(sfep,arch)
167 #else
168 #define	XFS_DIR2_SF_GET_OFFSET_ARCH(sfep,arch)	\
169 	INT_GET_UNALIGNED_16_ARCH(&(sfep)->offset.i,arch)
170 #endif
171 
172 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_PUT_OFFSET)
173 void xfs_dir2_sf_put_offset_arch(xfs_dir2_sf_entry_t *sfep,
174 				    xfs_dir2_data_aoff_t off, xfs_arch_t arch);
175 #define	XFS_DIR2_SF_PUT_OFFSET_ARCH(sfep,off,arch) \
176 	xfs_dir2_sf_put_offset_arch(sfep,off,arch)
177 #else
178 #define	XFS_DIR2_SF_PUT_OFFSET_ARCH(sfep,off,arch)	\
179 	INT_SET_UNALIGNED_16_ARCH(&(sfep)->offset.i,off,arch)
180 #endif
181 
182 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_ENTSIZE_BYNAME)
183 int xfs_dir2_sf_entsize_byname(xfs_dir2_sf_t *sfp, int len);
184 #define XFS_DIR2_SF_ENTSIZE_BYNAME(sfp,len)	\
185 	xfs_dir2_sf_entsize_byname(sfp,len)
186 #else
187 #define XFS_DIR2_SF_ENTSIZE_BYNAME(sfp,len)	/* space a name uses */ \
188 	((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (len) - \
189 	 ((sfp)->hdr.i8count == 0) * \
190 	 ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
191 #endif
192 
193 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_ENTSIZE_BYENTRY)
194 int xfs_dir2_sf_entsize_byentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep);
195 #define XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)	\
196 	xfs_dir2_sf_entsize_byentry(sfp,sfep)
197 #else
198 #define XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)	/* space an entry uses */ \
199 	((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (sfep)->namelen - \
200 	 ((sfp)->hdr.i8count == 0) * \
201 	 ((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)))
202 #endif
203 
204 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_FIRSTENTRY)
205 xfs_dir2_sf_entry_t *xfs_dir2_sf_firstentry(xfs_dir2_sf_t *sfp);
206 #define XFS_DIR2_SF_FIRSTENTRY(sfp)	xfs_dir2_sf_firstentry(sfp)
207 #else
208 #define XFS_DIR2_SF_FIRSTENTRY(sfp)	/* first entry in struct */ \
209 	((xfs_dir2_sf_entry_t *) \
210 	 ((char *)(sfp) + XFS_DIR2_SF_HDR_SIZE(sfp->hdr.i8count)))
211 #endif
212 
213 #if XFS_WANT_FUNCS || (XFS_WANT_SPACE && XFSSO_XFS_DIR2_SF_NEXTENTRY)
214 xfs_dir2_sf_entry_t *xfs_dir2_sf_nextentry(xfs_dir2_sf_t *sfp,
215 					   xfs_dir2_sf_entry_t *sfep);
216 #define XFS_DIR2_SF_NEXTENTRY(sfp,sfep)		xfs_dir2_sf_nextentry(sfp,sfep)
217 #else
218 #define XFS_DIR2_SF_NEXTENTRY(sfp,sfep)		/* next entry in struct */ \
219 	((xfs_dir2_sf_entry_t *) \
220 		((char *)(sfep) + XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)))
221 #endif
222 
223 /*
224  * Functions.
225  */
226 
227 extern int
228 	xfs_dir2_block_sfsize(struct xfs_inode *dp,
229 			      struct xfs_dir2_block *block,
230 			      xfs_dir2_sf_hdr_t *sfhp);
231 
232 extern int
233 	xfs_dir2_block_to_sf(struct xfs_da_args *args, struct xfs_dabuf *bp,
234 			     int size, xfs_dir2_sf_hdr_t *sfhp);
235 
236 extern int
237 	xfs_dir2_sf_addname(struct xfs_da_args *args);
238 
239 extern int
240 	xfs_dir2_sf_create(struct xfs_da_args *args, xfs_ino_t pino);
241 
242 extern int
243 	xfs_dir2_sf_getdents(struct xfs_inode *dp, struct uio *uio, int *eofp,
244 			     struct xfs_dirent *dbp, xfs_dir2_put_t put);
245 
246 extern int
247 	xfs_dir2_sf_lookup(struct xfs_da_args *args);
248 
249 extern int
250 	xfs_dir2_sf_removename(struct xfs_da_args *args);
251 
252 extern int
253 	xfs_dir2_sf_replace(struct xfs_da_args *args);
254 
255 #endif	/* __XFS_DIR2_SF_H__ */
256