alistair23-linux/fs/sysv/sysv.h
Arjan van de Ven 4b6f5d20b0 [PATCH] Make most file operations structs in fs/ const
This is a conversion to make the various file_operations structs in fs/
const.  Basically a regexp job, with a few manual fixups

The goal is both to increase correctness (harder to accidentally write to
shared datastructures) and reducing the false sharing of cachelines with
things that get dirty in .data (while .rodata is nicely read only and thus
cache clean)

Signed-off-by: Arjan van de Ven <arjan@infradead.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
2006-03-28 09:16:06 -08:00

245 lines
7.7 KiB
C

#ifndef _SYSV_H
#define _SYSV_H
#include <linux/buffer_head.h>
typedef __u16 __bitwise __fs16;
typedef __u32 __bitwise __fs32;
#include <linux/sysv_fs.h>
/*
* SystemV/V7/Coherent super-block data in memory
*
* The SystemV/V7/Coherent superblock contains dynamic data (it gets modified
* while the system is running). This is in contrast to the Minix and Berkeley
* filesystems (where the superblock is never modified). This affects the
* sync() operation: we must keep the superblock in a disk buffer and use this
* one as our "working copy".
*/
struct sysv_sb_info {
struct super_block *s_sb; /* VFS superblock */
int s_type; /* file system type: FSTYPE_{XENIX|SYSV|COH} */
char s_bytesex; /* bytesex (le/be/pdp) */
char s_truncate; /* if 1: names > SYSV_NAMELEN chars are truncated */
/* if 0: they are disallowed (ENAMETOOLONG) */
nlink_t s_link_max; /* max number of hard links to a file */
unsigned int s_inodes_per_block; /* number of inodes per block */
unsigned int s_inodes_per_block_1; /* inodes_per_block - 1 */
unsigned int s_inodes_per_block_bits; /* log2(inodes_per_block) */
unsigned int s_ind_per_block; /* number of indirections per block */
unsigned int s_ind_per_block_bits; /* log2(ind_per_block) */
unsigned int s_ind_per_block_2; /* ind_per_block ^ 2 */
unsigned int s_toobig_block; /* 10 + ipb + ipb^2 + ipb^3 */
unsigned int s_block_base; /* physical block number of block 0 */
unsigned short s_fic_size; /* free inode cache size, NICINOD */
unsigned short s_flc_size; /* free block list chunk size, NICFREE */
/* The superblock is kept in one or two disk buffers: */
struct buffer_head *s_bh1;
struct buffer_head *s_bh2;
/* These are pointers into the disk buffer, to compensate for
different superblock layout. */
char * s_sbd1; /* entire superblock data, for part 1 */
char * s_sbd2; /* entire superblock data, for part 2 */
__fs16 *s_sb_fic_count; /* pointer to s_sbd->s_ninode */
sysv_ino_t *s_sb_fic_inodes; /* pointer to s_sbd->s_inode */
__fs16 *s_sb_total_free_inodes; /* pointer to s_sbd->s_tinode */
__fs16 *s_bcache_count; /* pointer to s_sbd->s_nfree */
sysv_zone_t *s_bcache; /* pointer to s_sbd->s_free */
__fs32 *s_free_blocks; /* pointer to s_sbd->s_tfree */
__fs32 *s_sb_time; /* pointer to s_sbd->s_time */
__fs32 *s_sb_state; /* pointer to s_sbd->s_state, only FSTYPE_SYSV */
/* We keep those superblock entities that don't change here;
this saves us an indirection and perhaps a conversion. */
u32 s_firstinodezone; /* index of first inode zone */
u32 s_firstdatazone; /* same as s_sbd->s_isize */
u32 s_ninodes; /* total number of inodes */
u32 s_ndatazones; /* total number of data zones */
u32 s_nzones; /* same as s_sbd->s_fsize */
u16 s_namelen; /* max length of dir entry */
int s_forced_ro;
};
/*
* SystemV/V7/Coherent FS inode data in memory
*/
struct sysv_inode_info {
__fs32 i_data[13];
u32 i_dir_start_lookup;
struct inode vfs_inode;
};
static inline struct sysv_inode_info *SYSV_I(struct inode *inode)
{
return list_entry(inode, struct sysv_inode_info, vfs_inode);
}
static inline struct sysv_sb_info *SYSV_SB(struct super_block *sb)
{
return sb->s_fs_info;
}
/* identify the FS in memory */
enum {
FSTYPE_NONE = 0,
FSTYPE_XENIX,
FSTYPE_SYSV4,
FSTYPE_SYSV2,
FSTYPE_COH,
FSTYPE_V7,
FSTYPE_AFS,
FSTYPE_END,
};
#define SYSV_MAGIC_BASE 0x012FF7B3
#define XENIX_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_XENIX)
#define SYSV4_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV4)
#define SYSV2_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_SYSV2)
#define COH_SUPER_MAGIC (SYSV_MAGIC_BASE+FSTYPE_COH)
/* Admissible values for i_nlink: 0.._LINK_MAX */
enum {
XENIX_LINK_MAX = 126, /* ?? */
SYSV_LINK_MAX = 126, /* 127? 251? */
V7_LINK_MAX = 126, /* ?? */
COH_LINK_MAX = 10000,
};
static inline void dirty_sb(struct super_block *sb)
{
struct sysv_sb_info *sbi = SYSV_SB(sb);
mark_buffer_dirty(sbi->s_bh1);
if (sbi->s_bh1 != sbi->s_bh2)
mark_buffer_dirty(sbi->s_bh2);
sb->s_dirt = 1;
}
/* ialloc.c */
extern struct sysv_inode *sysv_raw_inode(struct super_block *, unsigned,
struct buffer_head **);
extern struct inode * sysv_new_inode(const struct inode *, mode_t);
extern void sysv_free_inode(struct inode *);
extern unsigned long sysv_count_free_inodes(struct super_block *);
/* balloc.c */
extern sysv_zone_t sysv_new_block(struct super_block *);
extern void sysv_free_block(struct super_block *, sysv_zone_t);
extern unsigned long sysv_count_free_blocks(struct super_block *);
/* itree.c */
extern void sysv_truncate(struct inode *);
/* inode.c */
extern int sysv_write_inode(struct inode *, int);
extern int sysv_sync_inode(struct inode *);
extern int sysv_sync_file(struct file *, struct dentry *, int);
extern void sysv_set_inode(struct inode *, dev_t);
extern int sysv_getattr(struct vfsmount *, struct dentry *, struct kstat *);
/* dir.c */
extern struct sysv_dir_entry *sysv_find_entry(struct dentry *, struct page **);
extern int sysv_add_link(struct dentry *, struct inode *);
extern int sysv_delete_entry(struct sysv_dir_entry *, struct page *);
extern int sysv_make_empty(struct inode *, struct inode *);
extern int sysv_empty_dir(struct inode *);
extern void sysv_set_link(struct sysv_dir_entry *, struct page *,
struct inode *);
extern struct sysv_dir_entry *sysv_dotdot(struct inode *, struct page **);
extern ino_t sysv_inode_by_name(struct dentry *);
extern struct inode_operations sysv_file_inode_operations;
extern struct inode_operations sysv_dir_inode_operations;
extern struct inode_operations sysv_fast_symlink_inode_operations;
extern const struct file_operations sysv_file_operations;
extern const struct file_operations sysv_dir_operations;
extern struct address_space_operations sysv_aops;
extern struct super_operations sysv_sops;
extern struct dentry_operations sysv_dentry_operations;
enum {
BYTESEX_LE,
BYTESEX_PDP,
BYTESEX_BE,
};
static inline u32 PDP_swab(u32 x)
{
#ifdef __LITTLE_ENDIAN
return ((x & 0xffff) << 16) | ((x & 0xffff0000) >> 16);
#else
#ifdef __BIG_ENDIAN
return ((x & 0xff00ff) << 8) | ((x & 0xff00ff00) >> 8);
#else
#error BYTESEX
#endif
#endif
}
static inline __u32 fs32_to_cpu(struct sysv_sb_info *sbi, __fs32 n)
{
if (sbi->s_bytesex == BYTESEX_PDP)
return PDP_swab((__force __u32)n);
else if (sbi->s_bytesex == BYTESEX_LE)
return le32_to_cpu((__force __le32)n);
else
return be32_to_cpu((__force __be32)n);
}
static inline __fs32 cpu_to_fs32(struct sysv_sb_info *sbi, __u32 n)
{
if (sbi->s_bytesex == BYTESEX_PDP)
return (__force __fs32)PDP_swab(n);
else if (sbi->s_bytesex == BYTESEX_LE)
return (__force __fs32)cpu_to_le32(n);
else
return (__force __fs32)cpu_to_be32(n);
}
static inline __fs32 fs32_add(struct sysv_sb_info *sbi, __fs32 *n, int d)
{
if (sbi->s_bytesex == BYTESEX_PDP)
*(__u32*)n = PDP_swab(PDP_swab(*(__u32*)n)+d);
else if (sbi->s_bytesex == BYTESEX_LE)
*(__le32*)n = cpu_to_le32(le32_to_cpu(*(__le32*)n)+d);
else
*(__be32*)n = cpu_to_be32(be32_to_cpu(*(__be32*)n)+d);
return *n;
}
static inline __u16 fs16_to_cpu(struct sysv_sb_info *sbi, __fs16 n)
{
if (sbi->s_bytesex != BYTESEX_BE)
return le16_to_cpu((__force __le16)n);
else
return be16_to_cpu((__force __be16)n);
}
static inline __fs16 cpu_to_fs16(struct sysv_sb_info *sbi, __u16 n)
{
if (sbi->s_bytesex != BYTESEX_BE)
return (__force __fs16)cpu_to_le16(n);
else
return (__force __fs16)cpu_to_be16(n);
}
static inline __fs16 fs16_add(struct sysv_sb_info *sbi, __fs16 *n, int d)
{
if (sbi->s_bytesex != BYTESEX_BE)
*(__le16*)n = cpu_to_le16(le16_to_cpu(*(__le16 *)n)+d);
else
*(__be16*)n = cpu_to_be16(be16_to_cpu(*(__be16 *)n)+d);
return *n;
}
#endif /* _SYSV_H */