xref: /linux/fs/minix/minix.h (revision 7a4ffec9fd54ea27395e24dff726dbf58e2fe06b)
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  */
17 struct 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  */
28 struct 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 
45 struct inode *minix_iget(struct super_block *, unsigned long);
46 struct minix_inode *minix_V1_raw_inode(struct super_block *, ino_t, struct buffer_head **);
47 struct minix2_inode *minix_V2_raw_inode(struct super_block *, ino_t, struct buffer_head **);
48 struct inode *minix_new_inode(const struct inode *, umode_t);
49 void minix_free_inode(struct inode *inode);
50 unsigned long minix_count_free_inodes(struct super_block *sb);
51 int minix_new_block(struct inode *inode);
52 void minix_free_block(struct inode *inode, unsigned long block);
53 unsigned long minix_count_free_blocks(struct super_block *sb);
54 int minix_getattr(struct mnt_idmap *, const struct path *,
55 		struct kstat *, u32, unsigned int);
56 int minix_prepare_chunk(struct folio *folio, loff_t pos, unsigned len);
57 
58 extern void V1_minix_truncate(struct inode *);
59 extern void V2_minix_truncate(struct inode *);
60 extern void minix_truncate(struct inode *);
61 extern void minix_set_inode(struct inode *, dev_t);
62 extern int V1_minix_get_block(struct inode *, long, struct buffer_head *, int);
63 extern int V2_minix_get_block(struct inode *, long, struct buffer_head *, int);
64 extern unsigned V1_minix_blocks(loff_t, struct super_block *);
65 extern unsigned V2_minix_blocks(loff_t, struct super_block *);
66 
67 struct minix_dir_entry *minix_find_entry(struct dentry *, struct folio **);
68 int minix_add_link(struct dentry*, struct inode*);
69 int minix_delete_entry(struct minix_dir_entry *, struct folio *);
70 int minix_make_empty(struct inode*, struct inode*);
71 int minix_empty_dir(struct inode*);
72 int minix_set_link(struct minix_dir_entry *de, struct folio *folio,
73 		struct inode *inode);
74 struct minix_dir_entry *minix_dotdot(struct inode*, struct folio **);
75 ino_t minix_inode_by_name(struct dentry*);
76 
77 extern const struct inode_operations minix_file_inode_operations;
78 extern const struct inode_operations minix_dir_inode_operations;
79 extern const struct file_operations minix_file_operations;
80 extern const struct file_operations minix_dir_operations;
81 
82 static inline struct minix_sb_info *minix_sb(struct super_block *sb)
83 {
84 	return sb->s_fs_info;
85 }
86 
87 static inline struct minix_inode_info *minix_i(struct inode *inode)
88 {
89 	return container_of(inode, struct minix_inode_info, vfs_inode);
90 }
91 
92 static 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 
126 static 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 
151 static 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