xref: /linux/fs/hpfs/hpfs_fn.h (revision 93d90ad708b8da6efc0e487b66111aa9db7f70c7)
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 #ifdef pr_fmt
12 #undef pr_fmt
13 #endif
14 
15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
16 
17 #include <linux/mutex.h>
18 #include <linux/pagemap.h>
19 #include <linux/buffer_head.h>
20 #include <linux/slab.h>
21 #include <asm/unaligned.h>
22 
23 #include "hpfs.h"
24 
25 #define EIOERROR  EIO
26 #define EFSERROR  EPERM
27 #define EMEMERROR ENOMEM
28 
29 #define ANODE_ALLOC_FWD	512
30 #define FNODE_ALLOC_FWD	0
31 #define ALLOC_FWD_MIN	16
32 #define ALLOC_FWD_MAX	128
33 #define ALLOC_M		1
34 #define FNODE_RD_AHEAD	16
35 #define ANODE_RD_AHEAD	0
36 #define DNODE_RD_AHEAD	72
37 #define COUNT_RD_AHEAD	62
38 
39 #define FREE_DNODES_ADD	58
40 #define FREE_DNODES_DEL	29
41 
42 #define CHKCOND(x,y) if (!(x)) printk y
43 
44 struct hpfs_inode_info {
45 	loff_t mmu_private;
46 	ino_t i_parent_dir;	/* (directories) gives fnode of parent dir */
47 	unsigned i_dno;		/* (directories) root dnode */
48 	unsigned i_dpos;	/* (directories) temp for readdir */
49 	unsigned i_dsubdno;	/* (directories) temp for readdir */
50 	unsigned i_file_sec;	/* (files) minimalist cache of alloc info */
51 	unsigned i_disk_sec;	/* (files) minimalist cache of alloc info */
52 	unsigned i_n_secs;	/* (files) minimalist cache of alloc info */
53 	unsigned i_ea_size;	/* size of extended attributes */
54 	unsigned i_ea_mode : 1;	/* file's permission is stored in ea */
55 	unsigned i_ea_uid : 1;	/* file's uid is stored in ea */
56 	unsigned i_ea_gid : 1;	/* file's gid is stored in ea */
57 	unsigned i_dirty : 1;
58 	loff_t **i_rddir_off;
59 	struct inode vfs_inode;
60 };
61 
62 struct hpfs_sb_info {
63 	struct mutex hpfs_mutex;	/* global hpfs lock */
64 	ino_t sb_root;			/* inode number of root dir */
65 	unsigned sb_fs_size;		/* file system size, sectors */
66 	unsigned sb_bitmaps;		/* sector number of bitmap list */
67 	unsigned sb_dirband_start;	/* directory band start sector */
68 	unsigned sb_dirband_size;	/* directory band size, dnodes */
69 	unsigned sb_dmap;		/* sector number of dnode bit map */
70 	unsigned sb_n_free;		/* free blocks for statfs, or -1 */
71 	unsigned sb_n_free_dnodes;	/* free dnodes for statfs, or -1 */
72 	kuid_t sb_uid;			/* uid from mount options */
73 	kgid_t sb_gid;			/* gid from mount options */
74 	umode_t sb_mode;		/* mode from mount options */
75 	unsigned sb_eas : 2;		/* eas: 0-ignore, 1-ro, 2-rw */
76 	unsigned sb_err : 2;		/* on errs: 0-cont, 1-ro, 2-panic */
77 	unsigned sb_chk : 2;		/* checks: 0-no, 1-normal, 2-strict */
78 	unsigned sb_lowercase : 1;	/* downcase filenames hackery */
79 	unsigned sb_was_error : 1;	/* there was an error, set dirty flag */
80 	unsigned sb_chkdsk : 2;		/* chkdsk: 0-no, 1-on errs, 2-allways */
81 	unsigned char *sb_cp_table;	/* code page tables: */
82 					/* 	128 bytes uppercasing table & */
83 					/*	128 bytes lowercasing table */
84 	__le32 *sb_bmp_dir;		/* main bitmap directory */
85 	unsigned sb_c_bitmap;		/* current bitmap */
86 	unsigned sb_max_fwd_alloc;	/* max forwad allocation */
87 	int sb_timeshift;
88 	struct rcu_head rcu;
89 };
90 
91 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
92 
93 struct quad_buffer_head {
94 	struct buffer_head *bh[4];
95 	void *data;
96 };
97 
98 /* The b-tree down pointer from a dir entry */
99 
100 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
101 {
102   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
103   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
104 }
105 
106 /* The first dir entry in a dnode */
107 
108 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
109 {
110   return (void *) dnode->dirent;
111 }
112 
113 /* The end+1 of the dir entries */
114 
115 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
116 {
117   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)));
118   return (void *) dnode + le32_to_cpu(dnode->first_free);
119 }
120 
121 /* The dir entry after dir entry de */
122 
123 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
124 {
125   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)));
126   return (void *) de + le16_to_cpu(de->length);
127 }
128 
129 static inline struct extended_attribute *fnode_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));
132 }
133 
134 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
135 {
136 	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));
137 }
138 
139 static unsigned ea_valuelen(struct extended_attribute *ea)
140 {
141 	return ea->valuelen_lo + 256 * ea->valuelen_hi;
142 }
143 
144 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
145 {
146 	return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
147 }
148 
149 static inline secno ea_sec(struct extended_attribute *ea)
150 {
151 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
152 }
153 
154 static inline secno ea_len(struct extended_attribute *ea)
155 {
156 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
157 }
158 
159 static inline char *ea_data(struct extended_attribute *ea)
160 {
161 	return (char *)((char *)ea + 5 + ea->namelen);
162 }
163 
164 static inline unsigned de_size(int namelen, secno down_ptr)
165 {
166 	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
167 }
168 
169 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
170 {
171 	int a;
172 	int n;
173 	if (!dst || !src) return;
174 	a = dst->down;
175 	n = dst->not_8x3;
176 	memcpy((char *)dst + 2, (char *)src + 2, 28);
177 	dst->down = a;
178 	dst->not_8x3 = n;
179 }
180 
181 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
182 {
183 	int i;
184 	if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
185 	if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
186 	for (i = 1; i < n; i++)
187 		if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
188 			return i + 1;
189 	return 0;
190 }
191 
192 /* alloc.c */
193 
194 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
195 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
196 int hpfs_alloc_if_possible(struct super_block *, secno);
197 void hpfs_free_sectors(struct super_block *, secno, unsigned);
198 int hpfs_check_free_dnodes(struct super_block *, int);
199 void hpfs_free_dnode(struct super_block *, secno);
200 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
201 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
202 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
203 
204 /* anode.c */
205 
206 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
207 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
208 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
209 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
210 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
211 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
212 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
213 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
214 
215 /* buffer.c */
216 
217 void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
218 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
219 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
220 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
221 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
222 void hpfs_brelse4(struct quad_buffer_head *);
223 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
224 
225 /* dentry.c */
226 
227 extern const struct dentry_operations hpfs_dentry_operations;
228 
229 /* dir.c */
230 
231 struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
232 extern const struct file_operations hpfs_dir_ops;
233 
234 /* dnode.c */
235 
236 void hpfs_add_pos(struct inode *, loff_t *);
237 void hpfs_del_pos(struct inode *, loff_t *);
238 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
239 				const unsigned char *, unsigned, secno);
240 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
241 		    struct hpfs_dirent *);
242 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
243 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
244 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
245 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
246 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
247 			       const unsigned char *, unsigned, dnode_secno *,
248 			       struct quad_buffer_head *);
249 void hpfs_remove_dtree(struct super_block *, dnode_secno);
250 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
251 
252 /* ea.c */
253 
254 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
255 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
256 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
257 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
258 		 const char *, int);
259 
260 /* file.c */
261 
262 int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
263 void hpfs_truncate(struct inode *);
264 extern const struct file_operations hpfs_file_ops;
265 extern const struct inode_operations hpfs_file_iops;
266 extern const struct address_space_operations hpfs_aops;
267 
268 /* inode.c */
269 
270 void hpfs_init_inode(struct inode *);
271 void hpfs_read_inode(struct inode *);
272 void hpfs_write_inode(struct inode *);
273 void hpfs_write_inode_nolock(struct inode *);
274 int hpfs_setattr(struct dentry *, struct iattr *);
275 void hpfs_write_if_changed(struct inode *);
276 void hpfs_evict_inode(struct inode *);
277 
278 /* map.c */
279 
280 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
281 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
282 void hpfs_prefetch_bitmap(struct super_block *, unsigned);
283 unsigned char *hpfs_load_code_page(struct super_block *, secno);
284 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
285 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
286 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
287 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
288 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
289 
290 /* name.c */
291 
292 unsigned char hpfs_upcase(unsigned char *, unsigned char);
293 int hpfs_chk_name(const unsigned char *, unsigned *);
294 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
295 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
296 		       const unsigned char *, unsigned, int);
297 int hpfs_is_name_long(const unsigned char *, unsigned);
298 void hpfs_adjust_length(const unsigned char *, unsigned *);
299 
300 /* namei.c */
301 
302 extern const struct inode_operations hpfs_dir_iops;
303 extern const struct address_space_operations hpfs_symlink_aops;
304 
305 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
306 {
307 	return list_entry(inode, struct hpfs_inode_info, vfs_inode);
308 }
309 
310 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
311 {
312 	return sb->s_fs_info;
313 }
314 
315 /* super.c */
316 
317 __printf(2, 3)
318 void hpfs_error(struct super_block *, const char *, ...);
319 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
320 unsigned hpfs_get_free_dnodes(struct super_block *);
321 
322 /*
323  * local time (HPFS) to GMT (Unix)
324  */
325 
326 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
327 {
328 	extern struct timezone sys_tz;
329 	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
330 }
331 
332 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
333 {
334 	extern struct timezone sys_tz;
335 	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
336 }
337 
338 /*
339  * Locking:
340  *
341  * hpfs_lock() locks the whole filesystem. It must be taken
342  * on any method called by the VFS.
343  *
344  * We don't do any per-file locking anymore, it is hard to
345  * review and HPFS is not performance-sensitive anyway.
346  */
347 static inline void hpfs_lock(struct super_block *s)
348 {
349 	struct hpfs_sb_info *sbi = hpfs_sb(s);
350 	mutex_lock(&sbi->hpfs_mutex);
351 }
352 
353 static inline void hpfs_unlock(struct super_block *s)
354 {
355 	struct hpfs_sb_info *sbi = hpfs_sb(s);
356 	mutex_unlock(&sbi->hpfs_mutex);
357 }
358 
359 static inline void hpfs_lock_assert(struct super_block *s)
360 {
361 	struct hpfs_sb_info *sbi = hpfs_sb(s);
362 	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
363 }
364