1 | /* SPDX-License-Identifier: GPL-2.0 */ |
2 | #ifndef _SYSV_H |
3 | #define _SYSV_H |
4 | |
5 | #include <linux/buffer_head.h> |
6 | |
7 | typedef __u16 __bitwise __fs16; |
8 | typedef __u32 __bitwise __fs32; |
9 | |
10 | #include <linux/sysv_fs.h> |
11 | |
12 | /* |
13 | * SystemV/V7/Coherent super-block data in memory |
14 | * |
15 | * The SystemV/V7/Coherent superblock contains dynamic data (it gets modified |
16 | * while the system is running). This is in contrast to the Minix and Berkeley |
17 | * filesystems (where the superblock is never modified). This affects the |
18 | * sync() operation: we must keep the superblock in a disk buffer and use this |
19 | * one as our "working copy". |
20 | */ |
21 | |
22 | struct sysv_sb_info { |
23 | struct super_block *s_sb; /* VFS superblock */ |
24 | int s_type; /* file system type: FSTYPE_{XENIX|SYSV|COH} */ |
25 | char s_bytesex; /* bytesex (le/be/pdp) */ |
26 | unsigned int s_inodes_per_block; /* number of inodes per block */ |
27 | unsigned int s_inodes_per_block_1; /* inodes_per_block - 1 */ |
28 | unsigned int s_inodes_per_block_bits; /* log2(inodes_per_block) */ |
29 | unsigned int s_ind_per_block; /* number of indirections per block */ |
30 | unsigned int s_ind_per_block_bits; /* log2(ind_per_block) */ |
31 | unsigned int s_ind_per_block_2; /* ind_per_block ^ 2 */ |
32 | unsigned int s_toobig_block; /* 10 + ipb + ipb^2 + ipb^3 */ |
33 | unsigned int s_block_base; /* physical block number of block 0 */ |
34 | unsigned short s_fic_size; /* free inode cache size, NICINOD */ |
35 | unsigned short s_flc_size; /* free block list chunk size, NICFREE */ |
36 | /* The superblock is kept in one or two disk buffers: */ |
37 | struct buffer_head *s_bh1; |
38 | struct buffer_head *s_bh2; |
39 | /* These are pointers into the disk buffer, to compensate for |
40 | different superblock layout. */ |
41 | char * s_sbd1; /* entire superblock data, for part 1 */ |
42 | char * s_sbd2; /* entire superblock data, for part 2 */ |
43 | __fs16 *s_sb_fic_count; /* pointer to s_sbd->s_ninode */ |
44 | sysv_ino_t *s_sb_fic_inodes; /* pointer to s_sbd->s_inode */ |
45 | __fs16 *s_sb_total_free_inodes; /* pointer to s_sbd->s_tinode */ |
46 | __fs16 *s_bcache_count; /* pointer to s_sbd->s_nfree */ |
47 | sysv_zone_t *s_bcache; /* pointer to s_sbd->s_free */ |
48 | __fs32 *s_free_blocks; /* pointer to s_sbd->s_tfree */ |
49 | __fs32 *s_sb_time; /* pointer to s_sbd->s_time */ |
50 | __fs32 *s_sb_state; /* pointer to s_sbd->s_state, only FSTYPE_SYSV */ |
51 | /* We keep those superblock entities that don't change here; |
52 | this saves us an indirection and perhaps a conversion. */ |
53 | u32 s_firstinodezone; /* index of first inode zone */ |
54 | u32 s_firstdatazone; /* same as s_sbd->s_isize */ |
55 | u32 s_ninodes; /* total number of inodes */ |
56 | u32 s_ndatazones; /* total number of data zones */ |
57 | u32 s_nzones; /* same as s_sbd->s_fsize */ |
58 | u16 s_namelen; /* max length of dir entry */ |
59 | int s_forced_ro; |
60 | struct mutex s_lock; |
61 | }; |
62 | |
63 | /* |
64 | * SystemV/V7/Coherent FS inode data in memory |
65 | */ |
66 | struct sysv_inode_info { |
67 | __fs32 i_data[13]; |
68 | u32 i_dir_start_lookup; |
69 | struct inode vfs_inode; |
70 | }; |
71 | |
72 | |
73 | static inline struct sysv_inode_info *SYSV_I(struct inode *inode) |
74 | { |
75 | return container_of(inode, struct sysv_inode_info, vfs_inode); |
76 | } |
77 | |
78 | static inline struct sysv_sb_info *SYSV_SB(struct super_block *sb) |
79 | { |
80 | return sb->s_fs_info; |
81 | } |
82 | |
83 | |
84 | /* identify the FS in memory */ |
85 | enum { |
86 | FSTYPE_NONE = 0, |
87 | FSTYPE_XENIX, |
88 | FSTYPE_SYSV4, |
89 | FSTYPE_SYSV2, |
90 | FSTYPE_COH, |
91 | FSTYPE_V7, |
92 | FSTYPE_AFS, |
93 | FSTYPE_END, |
94 | }; |
95 | |
96 | #define SYSV_MAGIC_BASE 0x012FF7B3 |
97 | |
98 | #define XENIX_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_XENIX) |
99 | #define SYSV4_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV4) |
100 | #define SYSV2_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV2) |
101 | #define COH_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_COH) |
102 | |
103 | |
104 | /* Admissible values for i_nlink: 0.._LINK_MAX */ |
105 | enum { |
106 | XENIX_LINK_MAX = 126, /* ?? */ |
107 | SYSV_LINK_MAX = 126, /* 127? 251? */ |
108 | V7_LINK_MAX = 126, /* ?? */ |
109 | COH_LINK_MAX = 10000, |
110 | }; |
111 | |
112 | |
113 | static inline void dirty_sb(struct super_block *sb) |
114 | { |
115 | struct sysv_sb_info *sbi = SYSV_SB(sb); |
116 | |
117 | mark_buffer_dirty(bh: sbi->s_bh1); |
118 | if (sbi->s_bh1 != sbi->s_bh2) |
119 | mark_buffer_dirty(bh: sbi->s_bh2); |
120 | } |
121 | |
122 | |
123 | /* ialloc.c */ |
124 | extern struct sysv_inode *sysv_raw_inode(struct super_block *, unsigned, |
125 | struct buffer_head **); |
126 | extern struct inode * sysv_new_inode(const struct inode *, umode_t); |
127 | extern void sysv_free_inode(struct inode *); |
128 | extern unsigned long sysv_count_free_inodes(struct super_block *); |
129 | |
130 | /* balloc.c */ |
131 | extern sysv_zone_t sysv_new_block(struct super_block *); |
132 | extern void sysv_free_block(struct super_block *, sysv_zone_t); |
133 | extern unsigned long sysv_count_free_blocks(struct super_block *); |
134 | |
135 | /* itree.c */ |
136 | extern void sysv_truncate(struct inode *); |
137 | extern int sysv_prepare_chunk(struct page *page, loff_t pos, unsigned len); |
138 | |
139 | /* inode.c */ |
140 | extern struct inode *sysv_iget(struct super_block *, unsigned int); |
141 | extern int sysv_write_inode(struct inode *, struct writeback_control *wbc); |
142 | extern int sysv_sync_inode(struct inode *); |
143 | extern void sysv_set_inode(struct inode *, dev_t); |
144 | extern int sysv_getattr(struct mnt_idmap *, const struct path *, |
145 | struct kstat *, u32, unsigned int); |
146 | extern int sysv_init_icache(void); |
147 | extern void sysv_destroy_icache(void); |
148 | |
149 | |
150 | /* dir.c */ |
151 | extern struct sysv_dir_entry *sysv_find_entry(struct dentry *, struct page **); |
152 | extern int sysv_add_link(struct dentry *, struct inode *); |
153 | extern int sysv_delete_entry(struct sysv_dir_entry *, struct page *); |
154 | extern int sysv_make_empty(struct inode *, struct inode *); |
155 | extern int sysv_empty_dir(struct inode *); |
156 | extern int sysv_set_link(struct sysv_dir_entry *, struct page *, |
157 | struct inode *); |
158 | extern struct sysv_dir_entry *sysv_dotdot(struct inode *, struct page **); |
159 | extern ino_t sysv_inode_by_name(struct dentry *); |
160 | |
161 | |
162 | extern const struct inode_operations sysv_file_inode_operations; |
163 | extern const struct inode_operations sysv_dir_inode_operations; |
164 | extern const struct file_operations sysv_file_operations; |
165 | extern const struct file_operations sysv_dir_operations; |
166 | extern const struct address_space_operations sysv_aops; |
167 | extern const struct super_operations sysv_sops; |
168 | |
169 | |
170 | enum { |
171 | BYTESEX_LE, |
172 | BYTESEX_PDP, |
173 | BYTESEX_BE, |
174 | }; |
175 | |
176 | static inline u32 PDP_swab(u32 x) |
177 | { |
178 | #ifdef __LITTLE_ENDIAN |
179 | return ((x & 0xffff) << 16) | ((x & 0xffff0000) >> 16); |
180 | #else |
181 | #ifdef __BIG_ENDIAN |
182 | return ((x & 0xff00ff) << 8) | ((x & 0xff00ff00) >> 8); |
183 | #else |
184 | #error BYTESEX |
185 | #endif |
186 | #endif |
187 | } |
188 | |
189 | static inline __u32 fs32_to_cpu(struct sysv_sb_info *sbi, __fs32 n) |
190 | { |
191 | if (sbi->s_bytesex == BYTESEX_PDP) |
192 | return PDP_swab(x: (__force __u32)n); |
193 | else if (sbi->s_bytesex == BYTESEX_LE) |
194 | return le32_to_cpu((__force __le32)n); |
195 | else |
196 | return be32_to_cpu((__force __be32)n); |
197 | } |
198 | |
199 | static inline __fs32 cpu_to_fs32(struct sysv_sb_info *sbi, __u32 n) |
200 | { |
201 | if (sbi->s_bytesex == BYTESEX_PDP) |
202 | return (__force __fs32)PDP_swab(x: n); |
203 | else if (sbi->s_bytesex == BYTESEX_LE) |
204 | return (__force __fs32)cpu_to_le32(n); |
205 | else |
206 | return (__force __fs32)cpu_to_be32(n); |
207 | } |
208 | |
209 | static inline __fs32 fs32_add(struct sysv_sb_info *sbi, __fs32 *n, int d) |
210 | { |
211 | if (sbi->s_bytesex == BYTESEX_PDP) |
212 | *(__u32*)n = PDP_swab(x: PDP_swab(x: *(__u32*)n)+d); |
213 | else if (sbi->s_bytesex == BYTESEX_LE) |
214 | le32_add_cpu(var: (__le32 *)n, val: d); |
215 | else |
216 | be32_add_cpu(var: (__be32 *)n, val: d); |
217 | return *n; |
218 | } |
219 | |
220 | static inline __u16 fs16_to_cpu(struct sysv_sb_info *sbi, __fs16 n) |
221 | { |
222 | if (sbi->s_bytesex != BYTESEX_BE) |
223 | return le16_to_cpu((__force __le16)n); |
224 | else |
225 | return be16_to_cpu((__force __be16)n); |
226 | } |
227 | |
228 | static inline __fs16 cpu_to_fs16(struct sysv_sb_info *sbi, __u16 n) |
229 | { |
230 | if (sbi->s_bytesex != BYTESEX_BE) |
231 | return (__force __fs16)cpu_to_le16(n); |
232 | else |
233 | return (__force __fs16)cpu_to_be16(n); |
234 | } |
235 | |
236 | static inline __fs16 fs16_add(struct sysv_sb_info *sbi, __fs16 *n, int d) |
237 | { |
238 | if (sbi->s_bytesex != BYTESEX_BE) |
239 | le16_add_cpu(var: (__le16 *)n, val: d); |
240 | else |
241 | be16_add_cpu(var: (__be16 *)n, val: d); |
242 | return *n; |
243 | } |
244 | |
245 | #endif /* _SYSV_H */ |
246 | |