xref: /openbmc/linux/fs/hpfs/hpfs_fn.h (revision bc000245)
1 /*
2  *  linux/fs/hpfs/hpfs_fn.h
3  *
4  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5  *
6  *  function headers
7  */
8 
9 //#define DBG
10 //#define DEBUG_LOCKS
11 
12 #include <linux/mutex.h>
13 #include <linux/pagemap.h>
14 #include <linux/buffer_head.h>
15 #include <linux/slab.h>
16 #include <asm/unaligned.h>
17 
18 #include "hpfs.h"
19 
20 #define EIOERROR  EIO
21 #define EFSERROR  EPERM
22 #define EMEMERROR ENOMEM
23 
24 #define ANODE_ALLOC_FWD	512
25 #define FNODE_ALLOC_FWD	0
26 #define ALLOC_FWD_MIN	16
27 #define ALLOC_FWD_MAX	128
28 #define ALLOC_M		1
29 #define FNODE_RD_AHEAD	16
30 #define ANODE_RD_AHEAD	0
31 #define DNODE_RD_AHEAD	72
32 #define COUNT_RD_AHEAD	62
33 
34 #define FREE_DNODES_ADD	58
35 #define FREE_DNODES_DEL	29
36 
37 #define CHKCOND(x,y) if (!(x)) printk y
38 
39 struct hpfs_inode_info {
40 	loff_t mmu_private;
41 	ino_t i_parent_dir;	/* (directories) gives fnode of parent dir */
42 	unsigned i_dno;		/* (directories) root dnode */
43 	unsigned i_dpos;	/* (directories) temp for readdir */
44 	unsigned i_dsubdno;	/* (directories) temp for readdir */
45 	unsigned i_file_sec;	/* (files) minimalist cache of alloc info */
46 	unsigned i_disk_sec;	/* (files) minimalist cache of alloc info */
47 	unsigned i_n_secs;	/* (files) minimalist cache of alloc info */
48 	unsigned i_ea_size;	/* size of extended attributes */
49 	unsigned i_ea_mode : 1;	/* file's permission is stored in ea */
50 	unsigned i_ea_uid : 1;	/* file's uid is stored in ea */
51 	unsigned i_ea_gid : 1;	/* file's gid is stored in ea */
52 	unsigned i_dirty : 1;
53 	loff_t **i_rddir_off;
54 	struct inode vfs_inode;
55 };
56 
57 struct hpfs_sb_info {
58 	struct mutex hpfs_mutex;	/* global hpfs lock */
59 	ino_t sb_root;			/* inode number of root dir */
60 	unsigned sb_fs_size;		/* file system size, sectors */
61 	unsigned sb_bitmaps;		/* sector number of bitmap list */
62 	unsigned sb_dirband_start;	/* directory band start sector */
63 	unsigned sb_dirband_size;	/* directory band size, dnodes */
64 	unsigned sb_dmap;		/* sector number of dnode bit map */
65 	unsigned sb_n_free;		/* free blocks for statfs, or -1 */
66 	unsigned sb_n_free_dnodes;	/* free dnodes for statfs, or -1 */
67 	kuid_t sb_uid;			/* uid from mount options */
68 	kgid_t sb_gid;			/* gid from mount options */
69 	umode_t sb_mode;		/* mode from mount options */
70 	unsigned sb_eas : 2;		/* eas: 0-ignore, 1-ro, 2-rw */
71 	unsigned sb_err : 2;		/* on errs: 0-cont, 1-ro, 2-panic */
72 	unsigned sb_chk : 2;		/* checks: 0-no, 1-normal, 2-strict */
73 	unsigned sb_lowercase : 1;	/* downcase filenames hackery */
74 	unsigned sb_was_error : 1;	/* there was an error, set dirty flag */
75 	unsigned sb_chkdsk : 2;		/* chkdsk: 0-no, 1-on errs, 2-allways */
76 	unsigned char *sb_cp_table;	/* code page tables: */
77 					/* 	128 bytes uppercasing table & */
78 					/*	128 bytes lowercasing table */
79 	__le32 *sb_bmp_dir;		/* main bitmap directory */
80 	unsigned sb_c_bitmap;		/* current bitmap */
81 	unsigned sb_max_fwd_alloc;	/* max forwad allocation */
82 	int sb_timeshift;
83 	struct rcu_head rcu;
84 };
85 
86 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
87 
88 struct quad_buffer_head {
89 	struct buffer_head *bh[4];
90 	void *data;
91 };
92 
93 /* The b-tree down pointer from a dir entry */
94 
95 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
96 {
97   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
98   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
99 }
100 
101 /* The first dir entry in a dnode */
102 
103 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
104 {
105   return (void *) dnode->dirent;
106 }
107 
108 /* The end+1 of the dir entries */
109 
110 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
111 {
112   CHKCOND(le32_to_cpu(dnode->first_free)>=0x14 && le32_to_cpu(dnode->first_free)<=0xa00,("HPFS: dnode_end_de: dnode->first_free = %x\n",(unsigned)le32_to_cpu(dnode->first_free)));
113   return (void *) dnode + le32_to_cpu(dnode->first_free);
114 }
115 
116 /* The dir entry after dir entry de */
117 
118 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
119 {
120   CHKCOND(le16_to_cpu(de->length)>=0x20 && le16_to_cpu(de->length)<0x800,("HPFS: de_next_de: de->length = %x\n",(unsigned)le16_to_cpu(de->length)));
121   return (void *) de + le16_to_cpu(de->length);
122 }
123 
124 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
125 {
126 	return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
127 }
128 
129 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
130 {
131 	return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s) + le16_to_cpu(fnode->ea_size_s));
132 }
133 
134 static unsigned ea_valuelen(struct extended_attribute *ea)
135 {
136 	return ea->valuelen_lo + 256 * ea->valuelen_hi;
137 }
138 
139 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
140 {
141 	return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
142 }
143 
144 static inline secno ea_sec(struct extended_attribute *ea)
145 {
146 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
147 }
148 
149 static inline secno ea_len(struct extended_attribute *ea)
150 {
151 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
152 }
153 
154 static inline char *ea_data(struct extended_attribute *ea)
155 {
156 	return (char *)((char *)ea + 5 + ea->namelen);
157 }
158 
159 static inline unsigned de_size(int namelen, secno down_ptr)
160 {
161 	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
162 }
163 
164 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
165 {
166 	int a;
167 	int n;
168 	if (!dst || !src) return;
169 	a = dst->down;
170 	n = dst->not_8x3;
171 	memcpy((char *)dst + 2, (char *)src + 2, 28);
172 	dst->down = a;
173 	dst->not_8x3 = n;
174 }
175 
176 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
177 {
178 	int i;
179 	if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
180 	if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
181 	for (i = 1; i < n; i++)
182 		if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
183 			return i + 1;
184 	return 0;
185 }
186 
187 /* alloc.c */
188 
189 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
190 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
191 int hpfs_alloc_if_possible(struct super_block *, secno);
192 void hpfs_free_sectors(struct super_block *, secno, unsigned);
193 int hpfs_check_free_dnodes(struct super_block *, int);
194 void hpfs_free_dnode(struct super_block *, secno);
195 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
196 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
197 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
198 
199 /* anode.c */
200 
201 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
202 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
203 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
204 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
205 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
206 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
207 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
208 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
209 
210 /* buffer.c */
211 
212 void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
213 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
214 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
215 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
216 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
217 void hpfs_brelse4(struct quad_buffer_head *);
218 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
219 
220 /* dentry.c */
221 
222 extern const struct dentry_operations hpfs_dentry_operations;
223 
224 /* dir.c */
225 
226 struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
227 extern const struct file_operations hpfs_dir_ops;
228 
229 /* dnode.c */
230 
231 void hpfs_add_pos(struct inode *, loff_t *);
232 void hpfs_del_pos(struct inode *, loff_t *);
233 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
234 				const unsigned char *, unsigned, secno);
235 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
236 		    struct hpfs_dirent *);
237 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
238 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
239 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
240 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
241 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
242 			       const unsigned char *, unsigned, dnode_secno *,
243 			       struct quad_buffer_head *);
244 void hpfs_remove_dtree(struct super_block *, dnode_secno);
245 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
246 
247 /* ea.c */
248 
249 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
250 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
251 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
252 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
253 		 const char *, int);
254 
255 /* file.c */
256 
257 int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
258 void hpfs_truncate(struct inode *);
259 extern const struct file_operations hpfs_file_ops;
260 extern const struct inode_operations hpfs_file_iops;
261 extern const struct address_space_operations hpfs_aops;
262 
263 /* inode.c */
264 
265 void hpfs_init_inode(struct inode *);
266 void hpfs_read_inode(struct inode *);
267 void hpfs_write_inode(struct inode *);
268 void hpfs_write_inode_nolock(struct inode *);
269 int hpfs_setattr(struct dentry *, struct iattr *);
270 void hpfs_write_if_changed(struct inode *);
271 void hpfs_evict_inode(struct inode *);
272 
273 /* map.c */
274 
275 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
276 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
277 void hpfs_prefetch_bitmap(struct super_block *, unsigned);
278 unsigned char *hpfs_load_code_page(struct super_block *, secno);
279 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
280 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
281 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
282 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
283 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
284 
285 /* name.c */
286 
287 unsigned char hpfs_upcase(unsigned char *, unsigned char);
288 int hpfs_chk_name(const unsigned char *, unsigned *);
289 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
290 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
291 		       const unsigned char *, unsigned, int);
292 int hpfs_is_name_long(const unsigned char *, unsigned);
293 void hpfs_adjust_length(const unsigned char *, unsigned *);
294 
295 /* namei.c */
296 
297 extern const struct inode_operations hpfs_dir_iops;
298 extern const struct address_space_operations hpfs_symlink_aops;
299 
300 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
301 {
302 	return list_entry(inode, struct hpfs_inode_info, vfs_inode);
303 }
304 
305 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
306 {
307 	return sb->s_fs_info;
308 }
309 
310 /* super.c */
311 
312 __printf(2, 3)
313 void hpfs_error(struct super_block *, const char *, ...);
314 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
315 unsigned hpfs_count_one_bitmap(struct super_block *, secno);
316 
317 /*
318  * local time (HPFS) to GMT (Unix)
319  */
320 
321 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
322 {
323 	extern struct timezone sys_tz;
324 	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
325 }
326 
327 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
328 {
329 	extern struct timezone sys_tz;
330 	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
331 }
332 
333 /*
334  * Locking:
335  *
336  * hpfs_lock() locks the whole filesystem. It must be taken
337  * on any method called by the VFS.
338  *
339  * We don't do any per-file locking anymore, it is hard to
340  * review and HPFS is not performance-sensitive anyway.
341  */
342 static inline void hpfs_lock(struct super_block *s)
343 {
344 	struct hpfs_sb_info *sbi = hpfs_sb(s);
345 	mutex_lock(&sbi->hpfs_mutex);
346 }
347 
348 static inline void hpfs_unlock(struct super_block *s)
349 {
350 	struct hpfs_sb_info *sbi = hpfs_sb(s);
351 	mutex_unlock(&sbi->hpfs_mutex);
352 }
353 
354 static inline void hpfs_lock_assert(struct super_block *s)
355 {
356 	struct hpfs_sb_info *sbi = hpfs_sb(s);
357 	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
358 }
359