linux-stable/fs/adfs/adfs.h
Russell King 25e5d4df3b fs/adfs: mostly divorse inode number from indirect disc address
Avoid using the inode number as the indirect disc address, even though
these currently have the same value.

Signed-off-by: Russell King <rmk+kernel@armlinux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-01-20 20:12:42 -05:00

229 lines
6.5 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#include <linux/buffer_head.h>
#include <linux/fs.h>
#include <linux/adfs_fs.h>
/* Internal data structures for ADFS */
#define ADFS_FREE_FRAG 0
#define ADFS_BAD_FRAG 1
#define ADFS_ROOT_FRAG 2
#define ADFS_FILETYPE_NONE ((u16)~0)
/* RISC OS 12-bit filetype is stored in load_address[19:8] */
static inline u16 adfs_filetype(u32 loadaddr)
{
return (loadaddr & 0xfff00000) == 0xfff00000 ?
(loadaddr >> 8) & 0xfff : ADFS_FILETYPE_NONE;
}
#define ADFS_NDA_OWNER_READ (1 << 0)
#define ADFS_NDA_OWNER_WRITE (1 << 1)
#define ADFS_NDA_LOCKED (1 << 2)
#define ADFS_NDA_DIRECTORY (1 << 3)
#define ADFS_NDA_EXECUTE (1 << 4)
#define ADFS_NDA_PUBLIC_READ (1 << 5)
#define ADFS_NDA_PUBLIC_WRITE (1 << 6)
/*
* adfs file system inode data in memory
*/
struct adfs_inode_info {
loff_t mmu_private;
__u32 parent_id; /* parent indirect disc address */
__u32 indaddr; /* object indirect disc address */
__u32 loadaddr; /* RISC OS load address */
__u32 execaddr; /* RISC OS exec address */
unsigned int attr; /* RISC OS permissions */
struct inode vfs_inode;
};
static inline struct adfs_inode_info *ADFS_I(struct inode *inode)
{
return container_of(inode, struct adfs_inode_info, vfs_inode);
}
static inline bool adfs_inode_is_stamped(struct inode *inode)
{
return (ADFS_I(inode)->loadaddr & 0xfff00000) == 0xfff00000;
}
/*
* Forward-declare this
*/
struct adfs_discmap;
struct adfs_dir_ops;
/*
* ADFS file system superblock data in memory
*/
struct adfs_sb_info {
union { struct {
struct adfs_discmap *s_map; /* bh list containing map */
const struct adfs_dir_ops *s_dir; /* directory operations */
};
struct rcu_head rcu; /* used only at shutdown time */
};
kuid_t s_uid; /* owner uid */
kgid_t s_gid; /* owner gid */
umode_t s_owner_mask; /* ADFS owner perm -> unix perm */
umode_t s_other_mask; /* ADFS other perm -> unix perm */
int s_ftsuffix; /* ,xyz hex filetype suffix option */
__u32 s_ids_per_zone; /* max. no ids in one zone */
__u32 s_idlen; /* length of ID in map */
__u32 s_map_size; /* sector size of a map */
signed int s_map2blk; /* shift left by this for map->sector*/
unsigned int s_log2sharesize;/* log2 share size */
unsigned int s_namelen; /* maximum number of characters in name */
};
static inline struct adfs_sb_info *ADFS_SB(struct super_block *sb)
{
return sb->s_fs_info;
}
/*
* Directory handling
*/
struct adfs_dir {
struct super_block *sb;
int nr_buffers;
struct buffer_head *bh[4];
struct buffer_head **bhs;
unsigned int pos;
__u32 parent_id;
union {
struct adfs_dirheader *dirhead;
struct adfs_bigdirheader *bighead;
};
union {
struct adfs_newdirtail *newtail;
struct adfs_bigdirtail *bigtail;
};
};
/*
* This is the overall maximum name length
*/
#define ADFS_MAX_NAME_LEN (256 + 4) /* +4 for ,xyz hex filetype suffix */
struct object_info {
__u32 parent_id; /* parent object id */
__u32 indaddr; /* indirect disc addr */
__u32 loadaddr; /* load address */
__u32 execaddr; /* execution address */
__u32 size; /* size */
__u8 attr; /* RISC OS attributes */
unsigned int name_len; /* name length */
char name[ADFS_MAX_NAME_LEN];/* file name */
};
struct adfs_dir_ops {
int (*read)(struct super_block *sb, unsigned int indaddr,
unsigned int size, struct adfs_dir *dir);
int (*iterate)(struct adfs_dir *dir, struct dir_context *ctx);
int (*setpos)(struct adfs_dir *dir, unsigned int fpos);
int (*getnext)(struct adfs_dir *dir, struct object_info *obj);
int (*update)(struct adfs_dir *dir, struct object_info *obj);
int (*create)(struct adfs_dir *dir, struct object_info *obj);
int (*remove)(struct adfs_dir *dir, struct object_info *obj);
int (*commit)(struct adfs_dir *dir);
};
struct adfs_discmap {
struct buffer_head *dm_bh;
__u32 dm_startblk;
unsigned int dm_startbit;
unsigned int dm_endbit;
};
/* Inode stuff */
struct inode *adfs_iget(struct super_block *sb, struct object_info *obj);
int adfs_write_inode(struct inode *inode, struct writeback_control *wbc);
int adfs_notify_change(struct dentry *dentry, struct iattr *attr);
/* map.c */
int adfs_map_lookup(struct super_block *sb, u32 frag_id, unsigned int offset);
void adfs_map_statfs(struct super_block *sb, struct kstatfs *buf);
struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr);
void adfs_free_map(struct super_block *sb);
/* Misc */
__printf(3, 4)
void __adfs_error(struct super_block *sb, const char *function,
const char *fmt, ...);
#define adfs_error(sb, fmt...) __adfs_error(sb, __func__, fmt)
void adfs_msg(struct super_block *sb, const char *pfx, const char *fmt, ...);
/* super.c */
/*
* Inodes and file operations
*/
/* dir_*.c */
extern const struct inode_operations adfs_dir_inode_operations;
extern const struct file_operations adfs_dir_operations;
extern const struct dentry_operations adfs_dentry_operations;
extern const struct adfs_dir_ops adfs_f_dir_ops;
extern const struct adfs_dir_ops adfs_fplus_dir_ops;
int adfs_dir_copyfrom(void *dst, struct adfs_dir *dir, unsigned int offset,
size_t len);
int adfs_dir_copyto(struct adfs_dir *dir, unsigned int offset, const void *src,
size_t len);
void adfs_dir_relse(struct adfs_dir *dir);
int adfs_dir_read_buffers(struct super_block *sb, u32 indaddr,
unsigned int size, struct adfs_dir *dir);
void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj);
extern int adfs_dir_update(struct super_block *sb, struct object_info *obj,
int wait);
/* file.c */
extern const struct inode_operations adfs_file_inode_operations;
extern const struct file_operations adfs_file_operations;
static inline __u32 signed_asl(__u32 val, signed int shift)
{
if (shift >= 0)
val <<= shift;
else
val >>= -shift;
return val;
}
/*
* Calculate the address of a block in an object given the block offset
* and the object identity.
*
* The root directory ID should always be looked up in the map [3.4]
*/
static inline int __adfs_block_map(struct super_block *sb, u32 indaddr,
unsigned int block)
{
if (indaddr & 255) {
unsigned int off;
off = (indaddr & 255) - 1;
block += off << ADFS_SB(sb)->s_log2sharesize;
}
return adfs_map_lookup(sb, indaddr >> 8, block);
}
/* Return the disc record from the map */
static inline
struct adfs_discrecord *adfs_map_discrecord(struct adfs_discmap *dm)
{
return (void *)(dm[0].dm_bh->b_data + 4);
}
static inline u64 adfs_disc_size(const struct adfs_discrecord *dr)
{
return (u64)le32_to_cpu(dr->disc_size_high) << 32 |
le32_to_cpu(dr->disc_size);
}