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  1#ifndef _SYSV_H
  2#define _SYSV_H
  3
  4#include <linux/buffer_head.h>
  5
  6typedef __u16 __bitwise __fs16;
  7typedef __u32 __bitwise __fs32;
  8
  9#include <linux/sysv_fs.h>
 10
 11/*
 12 * SystemV/V7/Coherent super-block data in memory
 13 *
 14 * The SystemV/V7/Coherent superblock contains dynamic data (it gets modified
 15 * while the system is running). This is in contrast to the Minix and Berkeley
 16 * filesystems (where the superblock is never modified). This affects the
 17 * sync() operation: we must keep the superblock in a disk buffer and use this
 18 * one as our "working copy".
 19 */
 20
 21struct sysv_sb_info {
 22	struct super_block *s_sb;	/* VFS superblock */
 23	int	       s_type;		/* file system type: FSTYPE_{XENIX|SYSV|COH} */
 24	char	       s_bytesex;	/* bytesex (le/be/pdp) */
 25	char	       s_truncate;	/* if 1: names > SYSV_NAMELEN chars are truncated */
 26					/* if 0: they are disallowed (ENAMETOOLONG) */
 27	unsigned int   s_inodes_per_block;	/* number of inodes per block */
 28	unsigned int   s_inodes_per_block_1;	/* inodes_per_block - 1 */
 29	unsigned int   s_inodes_per_block_bits;	/* log2(inodes_per_block) */
 30	unsigned int   s_ind_per_block;		/* number of indirections per block */
 31	unsigned int   s_ind_per_block_bits;	/* log2(ind_per_block) */
 32	unsigned int   s_ind_per_block_2;	/* ind_per_block ^ 2 */
 33	unsigned int   s_toobig_block;		/* 10 + ipb + ipb^2 + ipb^3 */
 34	unsigned int   s_block_base;	/* physical block number of block 0 */
 35	unsigned short s_fic_size;	/* free inode cache size, NICINOD */
 36	unsigned short s_flc_size;	/* free block list chunk size, NICFREE */
 37	/* The superblock is kept in one or two disk buffers: */
 38	struct buffer_head *s_bh1;
 39	struct buffer_head *s_bh2;
 40	/* These are pointers into the disk buffer, to compensate for
 41	   different superblock layout. */
 42	char *         s_sbd1;		/* entire superblock data, for part 1 */
 43	char *         s_sbd2;		/* entire superblock data, for part 2 */
 44	__fs16         *s_sb_fic_count;	/* pointer to s_sbd->s_ninode */
 45        sysv_ino_t     *s_sb_fic_inodes; /* pointer to s_sbd->s_inode */
 46	__fs16         *s_sb_total_free_inodes; /* pointer to s_sbd->s_tinode */
 47	__fs16         *s_bcache_count;	/* pointer to s_sbd->s_nfree */
 48	sysv_zone_t    *s_bcache;	/* pointer to s_sbd->s_free */
 49	__fs32         *s_free_blocks;	/* pointer to s_sbd->s_tfree */
 50	__fs32         *s_sb_time;	/* pointer to s_sbd->s_time */
 51	__fs32         *s_sb_state;	/* pointer to s_sbd->s_state, only FSTYPE_SYSV */
 52	/* We keep those superblock entities that don't change here;
 53	   this saves us an indirection and perhaps a conversion. */
 54	u32            s_firstinodezone; /* index of first inode zone */
 55	u32            s_firstdatazone;	/* same as s_sbd->s_isize */
 56	u32            s_ninodes;	/* total number of inodes */
 57	u32            s_ndatazones;	/* total number of data zones */
 58	u32            s_nzones;	/* same as s_sbd->s_fsize */
 59	u16	       s_namelen;       /* max length of dir entry */
 60	int	       s_forced_ro;
 61};
 62
 63/*
 64 * SystemV/V7/Coherent FS inode data in memory
 65 */
 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 list_entry(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		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 */
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	sb->s_dirt = 1;
121}
122
123
124/* ialloc.c */
125extern struct sysv_inode *sysv_raw_inode(struct super_block *, unsigned,
126			struct buffer_head **);
127extern struct inode * sysv_new_inode(const struct inode *, umode_t);
128extern void sysv_free_inode(struct inode *);
129extern unsigned long sysv_count_free_inodes(struct super_block *);
130
131/* balloc.c */
132extern sysv_zone_t sysv_new_block(struct super_block *);
133extern void sysv_free_block(struct super_block *, sysv_zone_t);
134extern unsigned long sysv_count_free_blocks(struct super_block *);
135
136/* itree.c */
137extern void sysv_truncate(struct inode *);
138extern int sysv_prepare_chunk(struct page *page, loff_t pos, unsigned len);
139
140/* inode.c */
141extern struct inode *sysv_iget(struct super_block *, unsigned int);
142extern int sysv_write_inode(struct inode *, struct writeback_control *wbc);
143extern int sysv_sync_inode(struct inode *);
144extern void sysv_set_inode(struct inode *, dev_t);
145extern int sysv_getattr(struct vfsmount *, struct dentry *, struct kstat *);
146extern int sysv_init_icache(void);
147extern void sysv_destroy_icache(void);
148
149
150/* dir.c */
151extern struct sysv_dir_entry *sysv_find_entry(struct dentry *, struct page **);
152extern int sysv_add_link(struct dentry *, struct inode *);
153extern int sysv_delete_entry(struct sysv_dir_entry *, struct page *);
154extern int sysv_make_empty(struct inode *, struct inode *);
155extern int sysv_empty_dir(struct inode *);
156extern void sysv_set_link(struct sysv_dir_entry *, struct page *,
157			struct inode *);
158extern struct sysv_dir_entry *sysv_dotdot(struct inode *, struct page **);
159extern ino_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 inode_operations sysv_fast_symlink_inode_operations;
165extern const struct file_operations sysv_file_operations;
166extern const struct file_operations sysv_dir_operations;
167extern const struct address_space_operations sysv_aops;
168extern const struct super_operations sysv_sops;
169extern const struct dentry_operations sysv_dentry_operations;
170
171
172enum {
173	BYTESEX_LE,
174	BYTESEX_PDP,
175	BYTESEX_BE,
176};
177
178static 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
191static 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
201static 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
211static 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
222static 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
230static 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
238static 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 */