xref: /openbmc/linux/fs/adfs/adfs.h (revision 4f89e4b8)
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 #include "dir_f.h"
30 
31 /*
32  * adfs file system inode data in memory
33  */
34 struct adfs_inode_info {
35 	loff_t		mmu_private;
36 	__u32		parent_id;	/* parent indirect disc address	*/
37 	__u32		loadaddr;	/* RISC OS load address		*/
38 	__u32		execaddr;	/* RISC OS exec address		*/
39 	unsigned int	attr;		/* RISC OS permissions		*/
40 	struct inode vfs_inode;
41 };
42 
43 static inline struct adfs_inode_info *ADFS_I(struct inode *inode)
44 {
45 	return container_of(inode, struct adfs_inode_info, vfs_inode);
46 }
47 
48 static inline bool adfs_inode_is_stamped(struct inode *inode)
49 {
50 	return (ADFS_I(inode)->loadaddr & 0xfff00000) == 0xfff00000;
51 }
52 
53 /*
54  * Forward-declare this
55  */
56 struct adfs_discmap;
57 struct adfs_dir_ops;
58 
59 /*
60  * ADFS file system superblock data in memory
61  */
62 struct adfs_sb_info {
63 	union { struct {
64 		struct adfs_discmap *s_map;	/* bh list containing map */
65 		const struct adfs_dir_ops *s_dir; /* directory operations */
66 		};
67 		struct rcu_head rcu;	/* used only at shutdown time	 */
68 	};
69 	kuid_t		s_uid;		/* owner uid */
70 	kgid_t		s_gid;		/* owner gid */
71 	umode_t		s_owner_mask;	/* ADFS owner perm -> unix perm */
72 	umode_t		s_other_mask;	/* ADFS other perm -> unix perm	*/
73 	int		s_ftsuffix;	/* ,xyz hex filetype suffix option */
74 
75 	__u32		s_ids_per_zone;	/* max. no ids in one zone */
76 	__u32		s_idlen;	/* length of ID in map */
77 	__u32		s_map_size;	/* sector size of a map	*/
78 	signed int	s_map2blk;	/* shift left by this for map->sector*/
79 	unsigned int	s_log2sharesize;/* log2 share size */
80 	unsigned int	s_namelen;	/* maximum number of characters in name	 */
81 };
82 
83 static inline struct adfs_sb_info *ADFS_SB(struct super_block *sb)
84 {
85 	return sb->s_fs_info;
86 }
87 
88 /*
89  * Directory handling
90  */
91 struct adfs_dir {
92 	struct super_block	*sb;
93 
94 	int			nr_buffers;
95 	struct buffer_head	*bh[4];
96 
97 	/* big directories need allocated buffers */
98 	struct buffer_head	**bh_fplus;
99 
100 	unsigned int		pos;
101 	__u32			parent_id;
102 
103 	struct adfs_dirheader	dirhead;
104 	union  adfs_dirtail	dirtail;
105 };
106 
107 /*
108  * This is the overall maximum name length
109  */
110 #define ADFS_MAX_NAME_LEN	(256 + 4) /* +4 for ,xyz hex filetype suffix */
111 struct object_info {
112 	__u32		parent_id;		/* parent object id	*/
113 	__u32		indaddr;		/* indirect disc addr	*/
114 	__u32		loadaddr;		/* load address		*/
115 	__u32		execaddr;		/* execution address	*/
116 	__u32		size;			/* size			*/
117 	__u8		attr;			/* RISC OS attributes	*/
118 	unsigned int	name_len;		/* name length		*/
119 	char		name[ADFS_MAX_NAME_LEN];/* file name		*/
120 };
121 
122 struct adfs_dir_ops {
123 	int	(*read)(struct super_block *sb, unsigned int indaddr,
124 			unsigned int size, struct adfs_dir *dir);
125 	int	(*setpos)(struct adfs_dir *dir, unsigned int fpos);
126 	int	(*getnext)(struct adfs_dir *dir, struct object_info *obj);
127 	int	(*update)(struct adfs_dir *dir, struct object_info *obj);
128 	int	(*create)(struct adfs_dir *dir, struct object_info *obj);
129 	int	(*remove)(struct adfs_dir *dir, struct object_info *obj);
130 	int	(*sync)(struct adfs_dir *dir);
131 	void	(*free)(struct adfs_dir *dir);
132 };
133 
134 struct adfs_discmap {
135 	struct buffer_head	*dm_bh;
136 	__u32			dm_startblk;
137 	unsigned int		dm_startbit;
138 	unsigned int		dm_endbit;
139 };
140 
141 /* Inode stuff */
142 struct inode *adfs_iget(struct super_block *sb, struct object_info *obj);
143 int adfs_write_inode(struct inode *inode, struct writeback_control *wbc);
144 int adfs_notify_change(struct dentry *dentry, struct iattr *attr);
145 
146 /* map.c */
147 int adfs_map_lookup(struct super_block *sb, u32 frag_id, unsigned int offset);
148 extern unsigned int adfs_map_free(struct super_block *sb);
149 
150 /* Misc */
151 __printf(3, 4)
152 void __adfs_error(struct super_block *sb, const char *function,
153 		  const char *fmt, ...);
154 #define adfs_error(sb, fmt...) __adfs_error(sb, __func__, fmt)
155 void adfs_msg(struct super_block *sb, const char *pfx, const char *fmt, ...);
156 
157 /* super.c */
158 
159 /*
160  * Inodes and file operations
161  */
162 
163 /* dir_*.c */
164 extern const struct inode_operations adfs_dir_inode_operations;
165 extern const struct file_operations adfs_dir_operations;
166 extern const struct dentry_operations adfs_dentry_operations;
167 extern const struct adfs_dir_ops adfs_f_dir_ops;
168 extern const struct adfs_dir_ops adfs_fplus_dir_ops;
169 
170 void adfs_object_fixup(struct adfs_dir *dir, struct object_info *obj);
171 extern int adfs_dir_update(struct super_block *sb, struct object_info *obj,
172 			   int wait);
173 
174 /* file.c */
175 extern const struct inode_operations adfs_file_inode_operations;
176 extern const struct file_operations adfs_file_operations;
177 
178 static inline __u32 signed_asl(__u32 val, signed int shift)
179 {
180 	if (shift >= 0)
181 		val <<= shift;
182 	else
183 		val >>= -shift;
184 	return val;
185 }
186 
187 /*
188  * Calculate the address of a block in an object given the block offset
189  * and the object identity.
190  *
191  * The root directory ID should always be looked up in the map [3.4]
192  */
193 static inline int __adfs_block_map(struct super_block *sb, u32 indaddr,
194 				   unsigned int block)
195 {
196 	if (indaddr & 255) {
197 		unsigned int off;
198 
199 		off = (indaddr & 255) - 1;
200 		block += off << ADFS_SB(sb)->s_log2sharesize;
201 	}
202 
203 	return adfs_map_lookup(sb, indaddr >> 8, block);
204 }
205 
206 /* Return the disc record from the map */
207 static inline
208 struct adfs_discrecord *adfs_map_discrecord(struct adfs_discmap *dm)
209 {
210 	return (void *)(dm[0].dm_bh->b_data + 4);
211 }
212 
213 static inline u64 adfs_disc_size(const struct adfs_discrecord *dr)
214 {
215 	return (u64)le32_to_cpu(dr->disc_size_high) << 32 |
216 		    le32_to_cpu(dr->disc_size);
217 }
218