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 char s_truncate; /* if 1: names > SYSV_NAMELEN chars are truncated */ 27 /* if 0: they are disallowed (ENAMETOOLONG) */ 28 unsigned int s_inodes_per_block; /* number of inodes per block */ 29 unsigned int s_inodes_per_block_1; /* inodes_per_block - 1 */ 30 unsigned int s_inodes_per_block_bits; /* log2(inodes_per_block) */ 31 unsigned int s_ind_per_block; /* number of indirections per block */ 32 unsigned int s_ind_per_block_bits; /* log2(ind_per_block) */ 33 unsigned int s_ind_per_block_2; /* ind_per_block ^ 2 */ 34 unsigned int s_toobig_block; /* 10 + ipb + ipb^2 + ipb^3 */ 35 unsigned int s_block_base; /* physical block number of block 0 */ 36 unsigned short s_fic_size; /* free inode cache size, NICINOD */ 37 unsigned short s_flc_size; /* free block list chunk size, NICFREE */ 38 /* The superblock is kept in one or two disk buffers: */ 39 struct buffer_head *s_bh1; 40 struct buffer_head *s_bh2; 41 /* These are pointers into the disk buffer, to compensate for 42 different superblock layout. */ 43 char * s_sbd1; /* entire superblock data, for part 1 */ 44 char * s_sbd2; /* entire superblock data, for part 2 */ 45 __fs16 *s_sb_fic_count; /* pointer to s_sbd->s_ninode */ 46 sysv_ino_t *s_sb_fic_inodes; /* pointer to s_sbd->s_inode */ 47 __fs16 *s_sb_total_free_inodes; /* pointer to s_sbd->s_tinode */ 48 __fs16 *s_bcache_count; /* pointer to s_sbd->s_nfree */ 49 sysv_zone_t *s_bcache; /* pointer to s_sbd->s_free */ 50 __fs32 *s_free_blocks; /* pointer to s_sbd->s_tfree */ 51 __fs32 *s_sb_time; /* pointer to s_sbd->s_time */ 52 __fs32 *s_sb_state; /* pointer to s_sbd->s_state, only FSTYPE_SYSV */ 53 /* We keep those superblock entities that don't change here; 54 this saves us an indirection and perhaps a conversion. */ 55 u32 s_firstinodezone; /* index of first inode zone */ 56 u32 s_firstdatazone; /* same as s_sbd->s_isize */ 57 u32 s_ninodes; /* total number of inodes */ 58 u32 s_ndatazones; /* total number of data zones */ 59 u32 s_nzones; /* same as s_sbd->s_fsize */ 60 u16 s_namelen; /* max length of dir entry */ 61 int s_forced_ro; 62 struct mutex s_lock; 63 }; 64 65 /* 66 * SystemV/V7/Coherent FS inode data in memory 67 */ 68 struct sysv_inode_info { 69 __fs32 i_data[13]; 70 u32 i_dir_start_lookup; 71 struct inode vfs_inode; 72 }; 73 74 75 static inline struct sysv_inode_info *SYSV_I(struct inode *inode) 76 { 77 return container_of(inode, struct sysv_inode_info, vfs_inode); 78 } 79 80 static inline struct sysv_sb_info *SYSV_SB(struct super_block *sb) 81 { 82 return sb->s_fs_info; 83 } 84 85 86 /* identify the FS in memory */ 87 enum { 88 FSTYPE_NONE = 0, 89 FSTYPE_XENIX, 90 FSTYPE_SYSV4, 91 FSTYPE_SYSV2, 92 FSTYPE_COH, 93 FSTYPE_V7, 94 FSTYPE_AFS, 95 FSTYPE_END, 96 }; 97 98 #define SYSV_MAGIC_BASE 0x012FF7B3 99 100 #define XENIX_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_XENIX) 101 #define SYSV4_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV4) 102 #define SYSV2_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV2) 103 #define COH_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_COH) 104 105 106 /* Admissible values for i_nlink: 0.._LINK_MAX */ 107 enum { 108 XENIX_LINK_MAX = 126, /* ?? */ 109 SYSV_LINK_MAX = 126, /* 127? 251? */ 110 V7_LINK_MAX = 126, /* ?? */ 111 COH_LINK_MAX = 10000, 112 }; 113 114 115 static inline void dirty_sb(struct super_block *sb) 116 { 117 struct sysv_sb_info *sbi = SYSV_SB(sb); 118 119 mark_buffer_dirty(sbi->s_bh1); 120 if (sbi->s_bh1 != sbi->s_bh2) 121 mark_buffer_dirty(sbi->s_bh2); 122 } 123 124 125 /* ialloc.c */ 126 extern struct sysv_inode *sysv_raw_inode(struct super_block *, unsigned, 127 struct buffer_head **); 128 extern struct inode * sysv_new_inode(const struct inode *, umode_t); 129 extern void sysv_free_inode(struct inode *); 130 extern unsigned long sysv_count_free_inodes(struct super_block *); 131 132 /* balloc.c */ 133 extern sysv_zone_t sysv_new_block(struct super_block *); 134 extern void sysv_free_block(struct super_block *, sysv_zone_t); 135 extern unsigned long sysv_count_free_blocks(struct super_block *); 136 137 /* itree.c */ 138 extern void sysv_truncate(struct inode *); 139 extern int sysv_prepare_chunk(struct page *page, loff_t pos, unsigned len); 140 141 /* inode.c */ 142 extern struct inode *sysv_iget(struct super_block *, unsigned int); 143 extern int sysv_write_inode(struct inode *, struct writeback_control *wbc); 144 extern int sysv_sync_inode(struct inode *); 145 extern void sysv_set_inode(struct inode *, dev_t); 146 extern int sysv_getattr(const struct path *, struct kstat *, u32, unsigned int); 147 extern int sysv_init_icache(void); 148 extern void sysv_destroy_icache(void); 149 150 151 /* dir.c */ 152 extern struct sysv_dir_entry *sysv_find_entry(struct dentry *, struct page **); 153 extern int sysv_add_link(struct dentry *, struct inode *); 154 extern int sysv_delete_entry(struct sysv_dir_entry *, struct page *); 155 extern int sysv_make_empty(struct inode *, struct inode *); 156 extern int sysv_empty_dir(struct inode *); 157 extern void sysv_set_link(struct sysv_dir_entry *, struct page *, 158 struct inode *); 159 extern struct sysv_dir_entry *sysv_dotdot(struct inode *, struct page **); 160 extern ino_t sysv_inode_by_name(struct dentry *); 161 162 163 extern const struct inode_operations sysv_file_inode_operations; 164 extern const struct inode_operations sysv_dir_inode_operations; 165 extern const struct file_operations sysv_file_operations; 166 extern const struct file_operations sysv_dir_operations; 167 extern const struct address_space_operations sysv_aops; 168 extern const struct super_operations sysv_sops; 169 extern const struct dentry_operations sysv_dentry_operations; 170 171 172 enum { 173 BYTESEX_LE, 174 BYTESEX_PDP, 175 BYTESEX_BE, 176 }; 177 178 static inline u32 PDP_swab(u32 x) 179 { 180 #ifdef __LITTLE_ENDIAN 181 return ((x & 0xffff) << 16) | ((x & 0xffff0000) >> 16); 182 #else 183 #ifdef __BIG_ENDIAN 184 return ((x & 0xff00ff) << 8) | ((x & 0xff00ff00) >> 8); 185 #else 186 #error BYTESEX 187 #endif 188 #endif 189 } 190 191 static inline __u32 fs32_to_cpu(struct sysv_sb_info *sbi, __fs32 n) 192 { 193 if (sbi->s_bytesex == BYTESEX_PDP) 194 return PDP_swab((__force __u32)n); 195 else if (sbi->s_bytesex == BYTESEX_LE) 196 return le32_to_cpu((__force __le32)n); 197 else 198 return be32_to_cpu((__force __be32)n); 199 } 200 201 static inline __fs32 cpu_to_fs32(struct sysv_sb_info *sbi, __u32 n) 202 { 203 if (sbi->s_bytesex == BYTESEX_PDP) 204 return (__force __fs32)PDP_swab(n); 205 else if (sbi->s_bytesex == BYTESEX_LE) 206 return (__force __fs32)cpu_to_le32(n); 207 else 208 return (__force __fs32)cpu_to_be32(n); 209 } 210 211 static inline __fs32 fs32_add(struct sysv_sb_info *sbi, __fs32 *n, int d) 212 { 213 if (sbi->s_bytesex == BYTESEX_PDP) 214 *(__u32*)n = PDP_swab(PDP_swab(*(__u32*)n)+d); 215 else if (sbi->s_bytesex == BYTESEX_LE) 216 le32_add_cpu((__le32 *)n, d); 217 else 218 be32_add_cpu((__be32 *)n, d); 219 return *n; 220 } 221 222 static inline __u16 fs16_to_cpu(struct sysv_sb_info *sbi, __fs16 n) 223 { 224 if (sbi->s_bytesex != BYTESEX_BE) 225 return le16_to_cpu((__force __le16)n); 226 else 227 return be16_to_cpu((__force __be16)n); 228 } 229 230 static inline __fs16 cpu_to_fs16(struct sysv_sb_info *sbi, __u16 n) 231 { 232 if (sbi->s_bytesex != BYTESEX_BE) 233 return (__force __fs16)cpu_to_le16(n); 234 else 235 return (__force __fs16)cpu_to_be16(n); 236 } 237 238 static inline __fs16 fs16_add(struct sysv_sb_info *sbi, __fs16 *n, int d) 239 { 240 if (sbi->s_bytesex != BYTESEX_BE) 241 le16_add_cpu((__le16 *)n, d); 242 else 243 be16_add_cpu((__be16 *)n, d); 244 return *n; 245 } 246 247 #endif /* _SYSV_H */ 248