1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef FS_MINIX_H
3#define FS_MINIX_H
4
5#include <linux/fs.h>
6#include <linux/pagemap.h>
7#include <linux/minix_fs.h>
8
9#define INODE_VERSION(inode)	minix_sb(inode->i_sb)->s_version
10#define MINIX_V1		0x0001		/* original minix fs */
11#define MINIX_V2		0x0002		/* minix V2 fs */
12#define MINIX_V3		0x0003		/* minix V3 fs */
13
14/*
15 * minix fs inode data in memory
16 */
17struct minix_inode_info {
18	union {
19		__u16 i1_data[16];
20		__u32 i2_data[16];
21	} u;
22	struct inode vfs_inode;
23};
24
25/*
26 * minix super-block data in memory
27 */
28struct minix_sb_info {
29	unsigned long s_ninodes;
30	unsigned long s_nzones;
31	unsigned long s_imap_blocks;
32	unsigned long s_zmap_blocks;
33	unsigned long s_firstdatazone;
34	unsigned long s_log_zone_size;
35	int s_dirsize;
36	int s_namelen;
37	struct buffer_head ** s_imap;
38	struct buffer_head ** s_zmap;
39	struct buffer_head * s_sbh;
40	struct minix_super_block * s_ms;
41	unsigned short s_mount_state;
42	unsigned short s_version;
43};
44
45extern struct inode *minix_iget(struct super_block *, unsigned long);
46extern struct minix_inode * minix_V1_raw_inode(struct super_block *, ino_t, struct buffer_head **);
47extern struct minix2_inode * minix_V2_raw_inode(struct super_block *, ino_t, struct buffer_head **);
48extern struct inode * minix_new_inode(const struct inode *, umode_t);
49extern void minix_free_inode(struct inode * inode);
50extern unsigned long minix_count_free_inodes(struct super_block *sb);
51extern int minix_new_block(struct inode * inode);
52extern void minix_free_block(struct inode *inode, unsigned long block);
53extern unsigned long minix_count_free_blocks(struct super_block *sb);
54extern int minix_getattr(struct mnt_idmap *, const struct path *,
55			 struct kstat *, u32, unsigned int);
56extern int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len);
57
58extern void V1_minix_truncate(struct inode *);
59extern void V2_minix_truncate(struct inode *);
60extern void minix_truncate(struct inode *);
61extern void minix_set_inode(struct inode *, dev_t);
62extern int V1_minix_get_block(struct inode *, long, struct buffer_head *, int);
63extern int V2_minix_get_block(struct inode *, long, struct buffer_head *, int);
64extern unsigned V1_minix_blocks(loff_t, struct super_block *);
65extern unsigned V2_minix_blocks(loff_t, struct super_block *);
66
67extern struct minix_dir_entry *minix_find_entry(struct dentry*, struct page**);
68extern int minix_add_link(struct dentry*, struct inode*);
69extern int minix_delete_entry(struct minix_dir_entry*, struct page*);
70extern int minix_make_empty(struct inode*, struct inode*);
71extern int minix_empty_dir(struct inode*);
72int minix_set_link(struct minix_dir_entry *de, struct page *page,
73		struct inode *inode);
74extern struct minix_dir_entry *minix_dotdot(struct inode*, struct page**);
75extern ino_t minix_inode_by_name(struct dentry*);
76
77extern const struct inode_operations minix_file_inode_operations;
78extern const struct inode_operations minix_dir_inode_operations;
79extern const struct file_operations minix_file_operations;
80extern const struct file_operations minix_dir_operations;
81
82static inline struct minix_sb_info *minix_sb(struct super_block *sb)
83{
84	return sb->s_fs_info;
85}
86
87static inline struct minix_inode_info *minix_i(struct inode *inode)
88{
89	return container_of(inode, struct minix_inode_info, vfs_inode);
90}
91
92static inline unsigned minix_blocks_needed(unsigned bits, unsigned blocksize)
93{
94	return DIV_ROUND_UP(bits, blocksize * 8);
95}
96
97#if defined(CONFIG_MINIX_FS_NATIVE_ENDIAN) && \
98	defined(CONFIG_MINIX_FS_BIG_ENDIAN_16BIT_INDEXED)
99
100#error Minix file system byte order broken
101
102#elif defined(CONFIG_MINIX_FS_NATIVE_ENDIAN)
103
104/*
105 * big-endian 32 or 64 bit indexed bitmaps on big-endian system or
106 * little-endian bitmaps on little-endian system
107 */
108
109#define minix_test_and_set_bit(nr, addr)	\
110	__test_and_set_bit((nr), (unsigned long *)(addr))
111#define minix_set_bit(nr, addr)		\
112	__set_bit((nr), (unsigned long *)(addr))
113#define minix_test_and_clear_bit(nr, addr) \
114	__test_and_clear_bit((nr), (unsigned long *)(addr))
115#define minix_test_bit(nr, addr)		\
116	test_bit((nr), (unsigned long *)(addr))
117#define minix_find_first_zero_bit(addr, size) \
118	find_first_zero_bit((unsigned long *)(addr), (size))
119
120#elif defined(CONFIG_MINIX_FS_BIG_ENDIAN_16BIT_INDEXED)
121
122/*
123 * big-endian 16bit indexed bitmaps
124 */
125
126static inline int minix_find_first_zero_bit(const void *vaddr, unsigned size)
127{
128	const unsigned short *p = vaddr, *addr = vaddr;
129	unsigned short num;
130
131	if (!size)
132		return 0;
133
134	size >>= 4;
135	while (*p++ == 0xffff) {
136		if (--size == 0)
137			return (p - addr) << 4;
138	}
139
140	num = *--p;
141	return ((p - addr) << 4) + ffz(num);
142}
143
144#define minix_test_and_set_bit(nr, addr)	\
145	__test_and_set_bit((nr) ^ 16, (unsigned long *)(addr))
146#define minix_set_bit(nr, addr)	\
147	__set_bit((nr) ^ 16, (unsigned long *)(addr))
148#define minix_test_and_clear_bit(nr, addr)	\
149	__test_and_clear_bit((nr) ^ 16, (unsigned long *)(addr))
150
151static inline int minix_test_bit(int nr, const void *vaddr)
152{
153	const unsigned short *p = vaddr;
154	return (p[nr >> 4] & (1U << (nr & 15))) != 0;
155}
156
157#else
158
159/*
160 * little-endian bitmaps
161 */
162
163#define minix_test_and_set_bit	__test_and_set_bit_le
164#define minix_set_bit		__set_bit_le
165#define minix_test_and_clear_bit	__test_and_clear_bit_le
166#define minix_test_bit	test_bit_le
167#define minix_find_first_zero_bit	find_first_zero_bit_le
168
169#endif
170
171#endif /* FS_MINIX_H */
172