xref: /openbmc/linux/fs/adfs/adfs.h (revision cf21eb6a)
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		 0
9 #define ADFS_BAD_FRAG		 1
10 #define ADFS_ROOT_FRAG		 2
11 
12 #define ADFS_FILETYPE_NONE	((u16)~0)
13 
14 /* RISC OS 12-bit filetype is stored in load_address[19:8] */
15 static 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 memory
31  */
32 struct 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 
42 static inline struct adfs_inode_info *ADFS_I(struct inode *inode)
43 {
44 	return container_of(inode, struct adfs_inode_info, vfs_inode);
45 }
46 
47 static inline bool adfs_inode_is_stamped(struct inode *inode)
48 {
49 	return (ADFS_I(inode)->loadaddr & 0xfff00000) == 0xfff00000;
50 }
51 
52 /*
53  * Forward-declare this
54  */
55 struct adfs_discmap;
56 struct adfs_dir_ops;
57 
58 /*
59  * ADFS file system superblock data in memory
60  */
61 struct 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 
82 static inline struct adfs_sb_info *ADFS_SB(struct super_block *sb)
83 {
84 	return sb->s_fs_info;
85 }
86 
87 /*
88  * Directory handling
89  */
90 struct 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 length
112  */
113 #define ADFS_MAX_NAME_LEN	(256 + 4) /* +4 for ,xyz hex filetype suffix */
114 struct 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 
125 struct 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 
137 struct 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 */
145 struct inode *adfs_iget(struct super_block *sb, struct object_info *obj);
146 int adfs_write_inode(struct inode *inode, struct writeback_control *wbc);
147 int adfs_notify_change(struct mnt_idmap *idmap, struct dentry *dentry,
148 		       struct iattr *attr);
149 
150 /* map.c */
151 int adfs_map_lookup(struct super_block *sb, u32 frag_id, unsigned int offset);
152 void adfs_map_statfs(struct super_block *sb, struct kstatfs *buf);
153 struct adfs_discmap *adfs_read_map(struct super_block *sb, struct adfs_discrecord *dr);
154 void adfs_free_map(struct super_block *sb);
155 
156 /* Misc */
157 __printf(3, 4)
158 void __adfs_error(struct super_block *sb, const char *function,
159 		  const char *fmt, ...);
160 #define adfs_error(sb, fmt...) __adfs_error(sb, __func__, fmt)
161 void adfs_msg(struct super_block *sb, const char *pfx, const char *fmt, ...);
162 
163 /* super.c */
164 
165 /*
166  * Inodes and file operations
167  */
168 
169 /* dir_*.c */
170 extern const struct inode_operations adfs_dir_inode_operations;
171 extern const struct file_operations adfs_dir_operations;
172 extern const struct dentry_operations adfs_dentry_operations;
173 extern const struct adfs_dir_ops adfs_f_dir_ops;
174 extern const struct adfs_dir_ops adfs_fplus_dir_ops;
175 
176 int adfs_dir_copyfrom(void *dst, struct adfs_dir *dir, unsigned int offset,
177 		      size_t len);
178 int adfs_dir_copyto(struct adfs_dir *dir, unsigned int offset, const void *src,
179 		    size_t len);
180 void adfs_dir_relse(struct adfs_dir *dir);
181 int adfs_dir_read_buffers(struct super_block *sb, u32 indaddr,
182 			  unsigned int size, struct adfs_dir *dir);
183 void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj);
184 extern int adfs_dir_update(struct super_block *sb, struct object_info *obj,
185 			   int wait);
186 
187 /* file.c */
188 extern const struct inode_operations adfs_file_inode_operations;
189 extern const struct file_operations adfs_file_operations;
190 
191 static inline __u32 signed_asl(__u32 val, signed int shift)
192 {
193 	if (shift >= 0)
194 		val <<= shift;
195 	else
196 		val >>= -shift;
197 	return val;
198 }
199 
200 /*
201  * Calculate the address of a block in an object given the block offset
202  * and the object identity.
203  *
204  * The root directory ID should always be looked up in the map [3.4]
205  */
206 static 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 */
220 static inline
221 struct adfs_discrecord *adfs_map_discrecord(struct adfs_discmap *dm)
222 {
223 	return (void *)(dm[0].dm_bh->b_data + 4);
224 }
225 
226 static 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