231 lines · c
1/* SPDX-License-Identifier: GPL-2.0 */2#include <linux/buffer_head.h>3#include <linux/fs.h>4#include <linux/adfs_fs.h>5 6/* Internal data structures for ADFS */7 8#define ADFS_FREE_FRAG 09#define ADFS_BAD_FRAG 110#define ADFS_ROOT_FRAG 211 12#define ADFS_FILETYPE_NONE ((u16)~0)13 14/* RISC OS 12-bit filetype is stored in load_address[19:8] */15static inline u16 adfs_filetype(u32 loadaddr)16{17 return (loadaddr & 0xfff00000) == 0xfff00000 ?18 (loadaddr >> 8) & 0xfff : ADFS_FILETYPE_NONE;19}20 21#define ADFS_NDA_OWNER_READ (1 << 0)22#define ADFS_NDA_OWNER_WRITE (1 << 1)23#define ADFS_NDA_LOCKED (1 << 2)24#define ADFS_NDA_DIRECTORY (1 << 3)25#define ADFS_NDA_EXECUTE (1 << 4)26#define ADFS_NDA_PUBLIC_READ (1 << 5)27#define ADFS_NDA_PUBLIC_WRITE (1 << 6)28 29/*30 * adfs file system inode data in memory31 */32struct adfs_inode_info {33 loff_t mmu_private;34 __u32 parent_id; /* parent indirect disc address */35 __u32 indaddr; /* object indirect disc address */36 __u32 loadaddr; /* RISC OS load address */37 __u32 execaddr; /* RISC OS exec address */38 unsigned int attr; /* RISC OS permissions */39 struct inode vfs_inode;40};41 42static inline struct adfs_inode_info *ADFS_I(struct inode *inode)43{44 return container_of(inode, struct adfs_inode_info, vfs_inode);45}46 47static inline bool adfs_inode_is_stamped(struct inode *inode)48{49 return (ADFS_I(inode)->loadaddr & 0xfff00000) == 0xfff00000;50}51 52/*53 * Forward-declare this54 */55struct adfs_discmap;56struct adfs_dir_ops;57 58/*59 * ADFS file system superblock data in memory60 */61struct adfs_sb_info {62 union { struct {63 struct adfs_discmap *s_map; /* bh list containing map */64 const struct adfs_dir_ops *s_dir; /* directory operations */65 };66 struct rcu_head rcu; /* used only at shutdown time */67 };68 kuid_t s_uid; /* owner uid */69 kgid_t s_gid; /* owner gid */70 umode_t s_owner_mask; /* ADFS owner perm -> unix perm */71 umode_t s_other_mask; /* ADFS other perm -> unix perm */72 int s_ftsuffix; /* ,xyz hex filetype suffix option */73 74 __u32 s_ids_per_zone; /* max. no ids in one zone */75 __u32 s_idlen; /* length of ID in map */76 __u32 s_map_size; /* sector size of a map */77 signed int s_map2blk; /* shift left by this for map->sector*/78 unsigned int s_log2sharesize;/* log2 share size */79 unsigned int s_namelen; /* maximum number of characters in name */80};81 82static inline struct adfs_sb_info *ADFS_SB(struct super_block *sb)83{84 return sb->s_fs_info;85}86 87/*88 * Directory handling89 */90struct adfs_dir {91 struct super_block *sb;92 93 int nr_buffers;94 struct buffer_head *bh[4];95 struct buffer_head **bhs;96 97 unsigned int pos;98 __u32 parent_id;99 100 union {101 struct adfs_dirheader *dirhead;102 struct adfs_bigdirheader *bighead;103 };104 union {105 struct adfs_newdirtail *newtail;106 struct adfs_bigdirtail *bigtail;107 };108};109 110/*111 * This is the overall maximum name length112 */113#define ADFS_MAX_NAME_LEN (256 + 4) /* +4 for ,xyz hex filetype suffix */114struct object_info {115 __u32 parent_id; /* parent object id */116 __u32 indaddr; /* indirect disc addr */117 __u32 loadaddr; /* load address */118 __u32 execaddr; /* execution address */119 __u32 size; /* size */120 __u8 attr; /* RISC OS attributes */121 unsigned int name_len; /* name length */122 char name[ADFS_MAX_NAME_LEN];/* file name */123};124 125struct adfs_dir_ops {126 int (*read)(struct super_block *sb, unsigned int indaddr,127 unsigned int size, struct adfs_dir *dir);128 int (*iterate)(struct adfs_dir *dir, struct dir_context *ctx);129 int (*setpos)(struct adfs_dir *dir, unsigned int fpos);130 int (*getnext)(struct adfs_dir *dir, struct object_info *obj);131 int (*update)(struct adfs_dir *dir, struct object_info *obj);132 int (*create)(struct adfs_dir *dir, struct object_info *obj);133 int (*remove)(struct adfs_dir *dir, struct object_info *obj);134 int (*commit)(struct adfs_dir *dir);135};136 137struct adfs_discmap {138 struct buffer_head *dm_bh;139 __u32 dm_startblk;140 unsigned int dm_startbit;141 unsigned int dm_endbit;142};143 144/* Inode stuff */145struct inode *adfs_iget(struct super_block *sb, struct object_info *obj);146int adfs_write_inode(struct inode *inode, struct writeback_control *wbc);147int adfs_notify_change(struct mnt_idmap *idmap, struct dentry *dentry,148 struct iattr *attr);149 150/* map.c */151int adfs_map_lookup(struct super_block *sb, u32 frag_id, unsigned int offset);152void adfs_map_statfs(struct super_block *sb, struct kstatfs *buf);153struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr);154void adfs_free_map(struct super_block *sb);155 156/* Misc */157__printf(3, 4)158void __adfs_error(struct super_block *sb, const char *function,159 const char *fmt, ...);160#define adfs_error(sb, fmt...) __adfs_error(sb, __func__, fmt)161void adfs_msg(struct super_block *sb, const char *pfx, const char *fmt, ...);162 163/* super.c */164 165/*166 * Inodes and file operations167 */168 169/* dir_*.c */170extern const struct inode_operations adfs_dir_inode_operations;171extern const struct file_operations adfs_dir_operations;172extern const struct dentry_operations adfs_dentry_operations;173extern const struct adfs_dir_ops adfs_f_dir_ops;174extern const struct adfs_dir_ops adfs_fplus_dir_ops;175 176int adfs_dir_copyfrom(void *dst, struct adfs_dir *dir, unsigned int offset,177 size_t len);178int adfs_dir_copyto(struct adfs_dir *dir, unsigned int offset, const void *src,179 size_t len);180void adfs_dir_relse(struct adfs_dir *dir);181int adfs_dir_read_buffers(struct super_block *sb, u32 indaddr,182 unsigned int size, struct adfs_dir *dir);183void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj);184extern int adfs_dir_update(struct super_block *sb, struct object_info *obj,185 int wait);186 187/* file.c */188extern const struct inode_operations adfs_file_inode_operations;189extern const struct file_operations adfs_file_operations;190 191static inline __u32 signed_asl(__u32 val, signed int shift)192{193 if (shift >= 0)194 val <<= shift;195 else196 val >>= -shift;197 return val;198}199 200/*201 * Calculate the address of a block in an object given the block offset202 * and the object identity.203 *204 * The root directory ID should always be looked up in the map [3.4]205 */206static inline int __adfs_block_map(struct super_block *sb, u32 indaddr,207 unsigned int block)208{209 if (indaddr & 255) {210 unsigned int off;211 212 off = (indaddr & 255) - 1;213 block += off << ADFS_SB(sb)->s_log2sharesize;214 }215 216 return adfs_map_lookup(sb, indaddr >> 8, block);217}218 219/* Return the disc record from the map */220static inline221struct adfs_discrecord *adfs_map_discrecord(struct adfs_discmap *dm)222{223 return (void *)(dm[0].dm_bh->b_data + 4);224}225 226static inline u64 adfs_disc_size(const struct adfs_discrecord *dr)227{228 return (u64)le32_to_cpu(dr->disc_size_high) << 32 |229 le32_to_cpu(dr->disc_size);230}231