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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _SYSV_H3#define _SYSV_H4 5#include <linux/buffer_head.h>6 7typedef __u16 __bitwise __fs16;8typedef __u32 __bitwise __fs32;9 10#include <linux/sysv_fs.h>11 12/*13 * SystemV/V7/Coherent super-block data in memory14 *15 * The SystemV/V7/Coherent superblock contains dynamic data (it gets modified16 * while the system is running). This is in contrast to the Minix and Berkeley17 * filesystems (where the superblock is never modified). This affects the18 * sync() operation: we must keep the superblock in a disk buffer and use this19 * one as our "working copy".20 */21 22struct 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 for40 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 memory65 */66struct sysv_inode_info {67 __fs32 i_data[13];68 u32 i_dir_start_lookup;69 struct inode vfs_inode;70};71 72 73static inline struct sysv_inode_info *SYSV_I(struct inode *inode)74{75 return container_of(inode, struct sysv_inode_info, vfs_inode);76}77 78static 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 */85enum {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 0x012FF7B397 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 */105enum {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 113static 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 */124extern struct sysv_inode *sysv_raw_inode(struct super_block *, unsigned,125 struct buffer_head **);126extern struct inode * sysv_new_inode(const struct inode *, umode_t);127extern void sysv_free_inode(struct inode *);128extern unsigned long sysv_count_free_inodes(struct super_block *);129 130/* balloc.c */131extern sysv_zone_t sysv_new_block(struct super_block *);132extern void sysv_free_block(struct super_block *, sysv_zone_t);133extern unsigned long sysv_count_free_blocks(struct super_block *);134 135/* itree.c */136void sysv_truncate(struct inode *);137int sysv_prepare_chunk(struct folio *folio, loff_t pos, unsigned len);138 139/* inode.c */140extern struct inode *sysv_iget(struct super_block *, unsigned int);141extern int sysv_write_inode(struct inode *, struct writeback_control *wbc);142extern int sysv_sync_inode(struct inode *);143extern void sysv_set_inode(struct inode *, dev_t);144extern int sysv_getattr(struct mnt_idmap *, const struct path *,145 struct kstat *, u32, unsigned int);146extern int sysv_init_icache(void);147extern void sysv_destroy_icache(void);148 149 150/* dir.c */151struct sysv_dir_entry *sysv_find_entry(struct dentry *, struct folio **);152int sysv_add_link(struct dentry *, struct inode *);153int sysv_delete_entry(struct sysv_dir_entry *, struct folio *);154int sysv_make_empty(struct inode *, struct inode *);155int sysv_empty_dir(struct inode *);156int sysv_set_link(struct sysv_dir_entry *, struct folio *,157 struct inode *);158struct sysv_dir_entry *sysv_dotdot(struct inode *, struct folio **);159ino_t sysv_inode_by_name(struct dentry *);160 161 162extern const struct inode_operations sysv_file_inode_operations;163extern const struct inode_operations sysv_dir_inode_operations;164extern const struct file_operations sysv_file_operations;165extern const struct file_operations sysv_dir_operations;166extern const struct address_space_operations sysv_aops;167extern const struct super_operations sysv_sops;168 169 170enum {171 BYTESEX_LE,172 BYTESEX_PDP,173 BYTESEX_BE,174};175 176static inline u32 PDP_swab(u32 x)177{178#ifdef __LITTLE_ENDIAN179 return ((x & 0xffff) << 16) | ((x & 0xffff0000) >> 16);180#else181#ifdef __BIG_ENDIAN182 return ((x & 0xff00ff) << 8) | ((x & 0xff00ff00) >> 8);183#else184#error BYTESEX185#endif186#endif187}188 189static 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 else196 return be32_to_cpu((__force __be32)n);197}198 199static 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 else206 return (__force __fs32)cpu_to_be32(n);207}208 209static 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 else216 be32_add_cpu((__be32 *)n, d);217 return *n;218}219 220static 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 else225 return be16_to_cpu((__force __be16)n);226}227 228static 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 else233 return (__force __fs16)cpu_to_be16(n);234}235 236static 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 else241 be16_add_cpu((__be16 *)n, d);242 return *n;243}244 245#endif /* _SYSV_H */246