xref: /openbmc/linux/fs/hpfs/hpfs_fn.h (revision 7dd29d8d865efdb00c0542a5d2c87af8c52ea6c7)
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 
17 #include "hpfs.h"
18 
19 #define EIOERROR  EIO
20 #define EFSERROR  EPERM
21 #define EMEMERROR ENOMEM
22 
23 #define ANODE_ALLOC_FWD	512
24 #define FNODE_ALLOC_FWD	0
25 #define ALLOC_FWD_MIN	16
26 #define ALLOC_FWD_MAX	128
27 #define ALLOC_M		1
28 #define FNODE_RD_AHEAD	16
29 #define ANODE_RD_AHEAD	16
30 #define DNODE_RD_AHEAD	4
31 
32 #define FREE_DNODES_ADD	58
33 #define FREE_DNODES_DEL	29
34 
35 #define CHKCOND(x,y) if (!(x)) printk y
36 
37 #ifdef DBG
38 #define PRINTK(x) printk x
39 #else
40 #undef PRINTK
41 #define PRINTK(x)
42 #endif
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_conv : 2;	/* (files) crlf->newline hackery */
55 	unsigned i_ea_mode : 1;	/* file's permission is stored in ea */
56 	unsigned i_ea_uid : 1;	/* file's uid is stored in ea */
57 	unsigned i_ea_gid : 1;	/* file's gid is stored in ea */
58 	unsigned i_dirty : 1;
59 	struct mutex i_mutex;
60 	struct mutex i_parent_mutex;
61 	loff_t **i_rddir_off;
62 	struct inode vfs_inode;
63 };
64 
65 struct hpfs_sb_info {
66 	struct mutex hpfs_mutex;	/* global hpfs lock */
67 	ino_t sb_root;			/* inode number of root dir */
68 	unsigned sb_fs_size;		/* file system size, sectors */
69 	unsigned sb_bitmaps;		/* sector number of bitmap list */
70 	unsigned sb_dirband_start;	/* directory band start sector */
71 	unsigned sb_dirband_size;	/* directory band size, dnodes */
72 	unsigned sb_dmap;		/* sector number of dnode bit map */
73 	unsigned sb_n_free;		/* free blocks for statfs, or -1 */
74 	unsigned sb_n_free_dnodes;	/* free dnodes for statfs, or -1 */
75 	uid_t sb_uid;			/* uid from mount options */
76 	gid_t sb_gid;			/* gid from mount options */
77 	umode_t sb_mode;		/* mode from mount options */
78 	unsigned sb_conv : 2;		/* crlf->newline hackery */
79 	unsigned sb_eas : 2;		/* eas: 0-ignore, 1-ro, 2-rw */
80 	unsigned sb_err : 2;		/* on errs: 0-cont, 1-ro, 2-panic */
81 	unsigned sb_chk : 2;		/* checks: 0-no, 1-normal, 2-strict */
82 	unsigned sb_lowercase : 1;	/* downcase filenames hackery */
83 	unsigned sb_was_error : 1;	/* there was an error, set dirty flag */
84 	unsigned sb_chkdsk : 2;		/* chkdsk: 0-no, 1-on errs, 2-allways */
85 	unsigned char *sb_cp_table;	/* code page tables: */
86 					/* 	128 bytes uppercasing table & */
87 					/*	128 bytes lowercasing table */
88 	unsigned *sb_bmp_dir;		/* main bitmap directory */
89 	unsigned sb_c_bitmap;		/* current bitmap */
90 	unsigned sb_max_fwd_alloc;	/* max forwad allocation */
91 	struct mutex hpfs_creation_de;	/* when creating dirents, nobody else
92 					   can alloc blocks */
93 	/*unsigned sb_mounting : 1;*/
94 	int sb_timeshift;
95 };
96 
97 /*
98  * conv= options
99  */
100 
101 #define CONV_BINARY 0			/* no conversion */
102 #define CONV_TEXT 1			/* crlf->newline */
103 #define CONV_AUTO 2			/* decide based on file contents */
104 
105 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
106 
107 struct quad_buffer_head {
108 	struct buffer_head *bh[4];
109 	void *data;
110 };
111 
112 /* The b-tree down pointer from a dir entry */
113 
114 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
115 {
116   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
117   return *(dnode_secno *) ((void *) de + de->length - 4);
118 }
119 
120 /* The first dir entry in a dnode */
121 
122 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
123 {
124   return (void *) dnode->dirent;
125 }
126 
127 /* The end+1 of the dir entries */
128 
129 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
130 {
131   CHKCOND(dnode->first_free>=0x14 && dnode->first_free<=0xa00,("HPFS: dnode_end_de: dnode->first_free = %d\n",(int)dnode->first_free));
132   return (void *) dnode + dnode->first_free;
133 }
134 
135 /* The dir entry after dir entry de */
136 
137 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
138 {
139   CHKCOND(de->length>=0x20 && de->length<0x800,("HPFS: de_next_de: de->length = %d\n",(int)de->length));
140   return (void *) de + de->length;
141 }
142 
143 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
144 {
145 	return (struct extended_attribute *)((char *)fnode + fnode->ea_offs + fnode->acl_size_s);
146 }
147 
148 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
149 {
150 	return (struct extended_attribute *)((char *)fnode + fnode->ea_offs + fnode->acl_size_s + fnode->ea_size_s);
151 }
152 
153 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
154 {
155 	return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea->valuelen);
156 }
157 
158 static inline secno ea_sec(struct extended_attribute *ea)
159 {
160 	return *(secno *)((char *)ea + 9 + ea->namelen);
161 }
162 
163 static inline secno ea_len(struct extended_attribute *ea)
164 {
165 	return *(secno *)((char *)ea + 5 + ea->namelen);
166 }
167 
168 static inline char *ea_data(struct extended_attribute *ea)
169 {
170 	return (char *)((char *)ea + 5 + ea->namelen);
171 }
172 
173 static inline unsigned de_size(int namelen, secno down_ptr)
174 {
175 	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
176 }
177 
178 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
179 {
180 	int a;
181 	int n;
182 	if (!dst || !src) return;
183 	a = dst->down;
184 	n = dst->not_8x3;
185 	memcpy((char *)dst + 2, (char *)src + 2, 28);
186 	dst->down = a;
187 	dst->not_8x3 = n;
188 }
189 
190 static inline unsigned tstbits(unsigned *bmp, unsigned b, unsigned n)
191 {
192 	int i;
193 	if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
194 	if (!((bmp[(b & 0x3fff) >> 5] >> (b & 0x1f)) & 1)) return 1;
195 	for (i = 1; i < n; i++)
196 		if (/*b+i < 0x4000 &&*/ !((bmp[((b+i) & 0x3fff) >> 5] >> ((b+i) & 0x1f)) & 1))
197 			return i + 1;
198 	return 0;
199 }
200 
201 /* alloc.c */
202 
203 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
204 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int, int);
205 int hpfs_alloc_if_possible(struct super_block *, secno);
206 void hpfs_free_sectors(struct super_block *, secno, unsigned);
207 int hpfs_check_free_dnodes(struct super_block *, int);
208 void hpfs_free_dnode(struct super_block *, secno);
209 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *, int);
210 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
211 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
212 
213 /* anode.c */
214 
215 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
216 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
217 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
218 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
219 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
220 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
221 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
222 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
223 
224 /* buffer.c */
225 
226 void hpfs_lock_creation(struct super_block *);
227 void hpfs_unlock_creation(struct super_block *);
228 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
229 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
230 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
231 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
232 void hpfs_brelse4(struct quad_buffer_head *);
233 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
234 
235 /* dentry.c */
236 
237 extern const struct dentry_operations hpfs_dentry_operations;
238 
239 /* dir.c */
240 
241 struct dentry *hpfs_lookup(struct inode *, struct dentry *, struct nameidata *);
242 extern const struct file_operations hpfs_dir_ops;
243 
244 /* dnode.c */
245 
246 void hpfs_add_pos(struct inode *, loff_t *);
247 void hpfs_del_pos(struct inode *, loff_t *);
248 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
249 				const unsigned char *, unsigned, secno);
250 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
251 		    struct hpfs_dirent *, int);
252 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
253 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
254 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
255 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
256 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
257 			       const unsigned char *, unsigned, dnode_secno *,
258 			       struct quad_buffer_head *);
259 void hpfs_remove_dtree(struct super_block *, dnode_secno);
260 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
261 
262 /* ea.c */
263 
264 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
265 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
266 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
267 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
268 		 const char *, int);
269 
270 /* file.c */
271 
272 int hpfs_file_fsync(struct file *, int);
273 extern const struct file_operations hpfs_file_ops;
274 extern const struct inode_operations hpfs_file_iops;
275 extern const struct address_space_operations hpfs_aops;
276 
277 /* inode.c */
278 
279 void hpfs_init_inode(struct inode *);
280 void hpfs_read_inode(struct inode *);
281 void hpfs_write_inode(struct inode *);
282 void hpfs_write_inode_nolock(struct inode *);
283 int hpfs_setattr(struct dentry *, struct iattr *);
284 void hpfs_write_if_changed(struct inode *);
285 void hpfs_evict_inode(struct inode *);
286 
287 /* map.c */
288 
289 unsigned *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
290 unsigned *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
291 unsigned char *hpfs_load_code_page(struct super_block *, secno);
292 secno *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
293 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
294 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
295 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
296 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
297 
298 /* name.c */
299 
300 unsigned char hpfs_upcase(unsigned char *, unsigned char);
301 int hpfs_chk_name(const unsigned char *, unsigned *);
302 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
303 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
304 		       const unsigned char *, unsigned, int);
305 int hpfs_is_name_long(const unsigned char *, unsigned);
306 void hpfs_adjust_length(const unsigned char *, unsigned *);
307 void hpfs_decide_conv(struct inode *, const unsigned char *, unsigned);
308 
309 /* namei.c */
310 
311 extern const struct inode_operations hpfs_dir_iops;
312 extern const struct address_space_operations hpfs_symlink_aops;
313 
314 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
315 {
316 	return list_entry(inode, struct hpfs_inode_info, vfs_inode);
317 }
318 
319 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
320 {
321 	return sb->s_fs_info;
322 }
323 
324 /* super.c */
325 
326 void hpfs_error(struct super_block *, const char *, ...)
327 	__attribute__((format (printf, 2, 3)));
328 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
329 unsigned hpfs_count_one_bitmap(struct super_block *, secno);
330 
331 /*
332  * local time (HPFS) to GMT (Unix)
333  */
334 
335 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
336 {
337 	extern struct timezone sys_tz;
338 	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
339 }
340 
341 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
342 {
343 	extern struct timezone sys_tz;
344 	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
345 }
346 
347 /*
348  * Locking:
349  *
350  * hpfs_lock() locks the whole filesystem. It must be taken
351  * on any method called by the VFS.
352  *
353  * We don't do any per-file locking anymore, it is hard to
354  * review and HPFS is not performance-sensitive anyway.
355  */
356 static inline void hpfs_lock(struct super_block *s)
357 {
358 	struct hpfs_sb_info *sbi = hpfs_sb(s);
359 	mutex_lock(&sbi->hpfs_mutex);
360 }
361 
362 static inline void hpfs_unlock(struct super_block *s)
363 {
364 	struct hpfs_sb_info *sbi = hpfs_sb(s);
365 	mutex_unlock(&sbi->hpfs_mutex);
366 }
367 
368 static inline void hpfs_lock_assert(struct super_block *s)
369 {
370 	struct hpfs_sb_info *sbi = hpfs_sb(s);
371 	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
372 }
373