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(sbi->s_bh1); 118 if (sbi->s_bh1 != sbi->s_bh2) 119 mark_buffer_dirty(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 user_namespace *, 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 void 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((__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(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(PDP_swab(*(__u32*)n)+d); 213 else if (sbi->s_bytesex == BYTESEX_LE) 214 le32_add_cpu((__le32 *)n, d); 215 else 216 be32_add_cpu((__be32 *)n, 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((__le16 *)n, d); 240 else 241 be16_add_cpu((__be16 *)n, d); 242 return *n; 243 } 244 245 #endif /* _SYSV_H */ 246