1/*
2 * Copyright (c) 2000-2001,2005 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_DIR2_SF_H__
19#define	__XFS_DIR2_SF_H__
20
21/*
22 * Directory layout when stored internal to an inode.
23 *
24 * Small directories are packed as tightly as possible so as to
25 * fit into the literal area of the inode.
26 */
27
28struct uio;
29struct xfs_dabuf;
30struct xfs_da_args;
31struct xfs_dir2_block;
32struct xfs_inode;
33struct xfs_mount;
34struct xfs_trans;
35
36/*
37 * Maximum size of a shortform directory.
38 */
39#define	XFS_DIR2_SF_MAX_SIZE	\
40	(XFS_DINODE_MAX_SIZE - (uint)sizeof(xfs_dinode_core_t) - \
41	 (uint)sizeof(xfs_agino_t))
42
43/*
44 * Inode number stored as 8 8-bit values.
45 */
46typedef	struct { __uint8_t i[8]; } xfs_dir2_ino8_t;
47
48/*
49 * Inode number stored as 4 8-bit values.
50 * Works a lot of the time, when all the inode numbers in a directory
51 * fit in 32 bits.
52 */
53typedef struct { __uint8_t i[4]; } xfs_dir2_ino4_t;
54
55typedef union {
56	xfs_dir2_ino8_t	i8;
57	xfs_dir2_ino4_t	i4;
58} xfs_dir2_inou_t;
59#define	XFS_DIR2_MAX_SHORT_INUM	((xfs_ino_t)0xffffffffULL)
60
61/*
62 * Normalized offset (in a data block) of the entry, really xfs_dir2_data_off_t.
63 * Only need 16 bits, this is the byte offset into the single block form.
64 */
65typedef struct { __uint8_t i[2]; } xfs_dir2_sf_off_t;
66
67/*
68 * The parent directory has a dedicated field, and the self-pointer must
69 * be calculated on the fly.
70 *
71 * Entries are packed toward the top as tightly as possible.  The header
72 * and the elements must be memcpy'd out into a work area to get correct
73 * alignment for the inode number fields.
74 */
75typedef struct xfs_dir2_sf_hdr {
76	__uint8_t		count;		/* count of entries */
77	__uint8_t		i8count;	/* count of 8-byte inode #s */
78	xfs_dir2_inou_t		parent;		/* parent dir inode number */
79} xfs_dir2_sf_hdr_t;
80
81typedef struct xfs_dir2_sf_entry {
82	__uint8_t		namelen;	/* actual name length */
83	xfs_dir2_sf_off_t	offset;		/* saved offset */
84	__uint8_t		name[1];	/* name, variable size */
85	xfs_dir2_inou_t		inumber;	/* inode number, var. offset */
86} xfs_dir2_sf_entry_t;
87
88typedef struct xfs_dir2_sf {
89	xfs_dir2_sf_hdr_t	hdr;		/* shortform header */
90	xfs_dir2_sf_entry_t	list[1];	/* shortform entries */
91} xfs_dir2_sf_t;
92
93#define	XFS_DIR2_SF_HDR_SIZE(i8count)	xfs_dir2_sf_hdr_size(i8count)
94static inline int xfs_dir2_sf_hdr_size(int i8count)
95{
96	return ((uint)sizeof(xfs_dir2_sf_hdr_t) - \
97		((i8count) == 0) * \
98		((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)));
99}
100
101#define	XFS_DIR2_SF_INUMBERP(sfep)	xfs_dir2_sf_inumberp(sfep)
102static inline xfs_dir2_inou_t *xfs_dir2_sf_inumberp(xfs_dir2_sf_entry_t *sfep)
103{
104	return (xfs_dir2_inou_t *)&(sfep)->name[(sfep)->namelen];
105}
106
107#define	XFS_DIR2_SF_GET_INUMBER(sfp, from) \
108	xfs_dir2_sf_get_inumber(sfp, from)
109static inline xfs_intino_t
110xfs_dir2_sf_get_inumber(xfs_dir2_sf_t *sfp, xfs_dir2_inou_t *from)
111{
112	return ((sfp)->hdr.i8count == 0 ? \
113		(xfs_intino_t)XFS_GET_DIR_INO4((from)->i4) : \
114		(xfs_intino_t)XFS_GET_DIR_INO8((from)->i8));
115}
116
117#define	XFS_DIR2_SF_PUT_INUMBER(sfp,from,to) \
118	xfs_dir2_sf_put_inumber(sfp,from,to)
119static inline void xfs_dir2_sf_put_inumber(xfs_dir2_sf_t *sfp, xfs_ino_t *from,
120						xfs_dir2_inou_t *to)
121{
122	if ((sfp)->hdr.i8count == 0)
123		XFS_PUT_DIR_INO4(*(from), (to)->i4);
124	else
125		XFS_PUT_DIR_INO8(*(from), (to)->i8);
126}
127
128#define	XFS_DIR2_SF_GET_OFFSET(sfep)	\
129	xfs_dir2_sf_get_offset(sfep)
130static inline xfs_dir2_data_aoff_t
131xfs_dir2_sf_get_offset(xfs_dir2_sf_entry_t *sfep)
132{
133	return INT_GET_UNALIGNED_16_BE(&(sfep)->offset.i);
134}
135
136#define	XFS_DIR2_SF_PUT_OFFSET(sfep,off) \
137	xfs_dir2_sf_put_offset(sfep,off)
138static inline void
139xfs_dir2_sf_put_offset(xfs_dir2_sf_entry_t *sfep, xfs_dir2_data_aoff_t off)
140{
141	INT_SET_UNALIGNED_16_BE(&(sfep)->offset.i, off);
142}
143
144#define XFS_DIR2_SF_ENTSIZE_BYNAME(sfp,len)	\
145	xfs_dir2_sf_entsize_byname(sfp,len)
146static inline int xfs_dir2_sf_entsize_byname(xfs_dir2_sf_t *sfp, int len)
147{
148	return ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (len) - \
149		((sfp)->hdr.i8count == 0) * \
150		((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)));
151}
152
153#define XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)	\
154	xfs_dir2_sf_entsize_byentry(sfp,sfep)
155static inline int
156xfs_dir2_sf_entsize_byentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep)
157{
158	return ((uint)sizeof(xfs_dir2_sf_entry_t) - 1 + (sfep)->namelen - \
159		((sfp)->hdr.i8count == 0) * \
160		((uint)sizeof(xfs_dir2_ino8_t) - (uint)sizeof(xfs_dir2_ino4_t)));
161}
162
163#define XFS_DIR2_SF_FIRSTENTRY(sfp)	xfs_dir2_sf_firstentry(sfp)
164static inline xfs_dir2_sf_entry_t *xfs_dir2_sf_firstentry(xfs_dir2_sf_t *sfp)
165{
166	return ((xfs_dir2_sf_entry_t *) \
167		((char *)(sfp) + XFS_DIR2_SF_HDR_SIZE(sfp->hdr.i8count)));
168}
169
170#define XFS_DIR2_SF_NEXTENTRY(sfp,sfep)	xfs_dir2_sf_nextentry(sfp,sfep)
171static inline xfs_dir2_sf_entry_t *
172xfs_dir2_sf_nextentry(xfs_dir2_sf_t *sfp, xfs_dir2_sf_entry_t *sfep)
173{
174	return ((xfs_dir2_sf_entry_t *) \
175		((char *)(sfep) + XFS_DIR2_SF_ENTSIZE_BYENTRY(sfp,sfep)));
176}
177
178/*
179 * Functions.
180 */
181extern int xfs_dir2_block_sfsize(struct xfs_inode *dp,
182				 struct xfs_dir2_block *block,
183				 xfs_dir2_sf_hdr_t *sfhp);
184extern int xfs_dir2_block_to_sf(struct xfs_da_args *args, struct xfs_dabuf *bp,
185				int size, xfs_dir2_sf_hdr_t *sfhp);
186extern int xfs_dir2_sf_addname(struct xfs_da_args *args);
187extern int xfs_dir2_sf_create(struct xfs_da_args *args, xfs_ino_t pino);
188extern int xfs_dir2_sf_getdents(struct xfs_inode *dp, struct uio *uio,
189				int *eofp, struct xfs_dirent *dbp,
190				xfs_dir2_put_t put);
191extern int xfs_dir2_sf_lookup(struct xfs_da_args *args);
192extern int xfs_dir2_sf_removename(struct xfs_da_args *args);
193extern int xfs_dir2_sf_replace(struct xfs_da_args *args);
194
195#endif	/* __XFS_DIR2_SF_H__ */
196