xref: /openbmc/linux/fs/hpfs/hpfs_fn.h (revision b9ccfda2)
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	16
31 #define DNODE_RD_AHEAD	4
32 
33 #define FREE_DNODES_ADD	58
34 #define FREE_DNODES_DEL	29
35 
36 #define CHKCOND(x,y) if (!(x)) printk y
37 
38 struct hpfs_inode_info {
39 	loff_t mmu_private;
40 	ino_t i_parent_dir;	/* (directories) gives fnode of parent dir */
41 	unsigned i_dno;		/* (directories) root dnode */
42 	unsigned i_dpos;	/* (directories) temp for readdir */
43 	unsigned i_dsubdno;	/* (directories) temp for readdir */
44 	unsigned i_file_sec;	/* (files) minimalist cache of alloc info */
45 	unsigned i_disk_sec;	/* (files) minimalist cache of alloc info */
46 	unsigned i_n_secs;	/* (files) minimalist cache of alloc info */
47 	unsigned i_ea_size;	/* size of extended attributes */
48 	unsigned i_ea_mode : 1;	/* file's permission is stored in ea */
49 	unsigned i_ea_uid : 1;	/* file's uid is stored in ea */
50 	unsigned i_ea_gid : 1;	/* file's gid is stored in ea */
51 	unsigned i_dirty : 1;
52 	loff_t **i_rddir_off;
53 	struct inode vfs_inode;
54 };
55 
56 struct hpfs_sb_info {
57 	struct mutex hpfs_mutex;	/* global hpfs lock */
58 	ino_t sb_root;			/* inode number of root dir */
59 	unsigned sb_fs_size;		/* file system size, sectors */
60 	unsigned sb_bitmaps;		/* sector number of bitmap list */
61 	unsigned sb_dirband_start;	/* directory band start sector */
62 	unsigned sb_dirband_size;	/* directory band size, dnodes */
63 	unsigned sb_dmap;		/* sector number of dnode bit map */
64 	unsigned sb_n_free;		/* free blocks for statfs, or -1 */
65 	unsigned sb_n_free_dnodes;	/* free dnodes for statfs, or -1 */
66 	uid_t sb_uid;			/* uid from mount options */
67 	gid_t sb_gid;			/* gid from mount options */
68 	umode_t sb_mode;		/* mode from mount options */
69 	unsigned sb_eas : 2;		/* eas: 0-ignore, 1-ro, 2-rw */
70 	unsigned sb_err : 2;		/* on errs: 0-cont, 1-ro, 2-panic */
71 	unsigned sb_chk : 2;		/* checks: 0-no, 1-normal, 2-strict */
72 	unsigned sb_lowercase : 1;	/* downcase filenames hackery */
73 	unsigned sb_was_error : 1;	/* there was an error, set dirty flag */
74 	unsigned sb_chkdsk : 2;		/* chkdsk: 0-no, 1-on errs, 2-allways */
75 	unsigned char *sb_cp_table;	/* code page tables: */
76 					/* 	128 bytes uppercasing table & */
77 					/*	128 bytes lowercasing table */
78 	__le32 *sb_bmp_dir;		/* main bitmap directory */
79 	unsigned sb_c_bitmap;		/* current bitmap */
80 	unsigned sb_max_fwd_alloc;	/* max forwad allocation */
81 	int sb_timeshift;
82 };
83 
84 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
85 
86 struct quad_buffer_head {
87 	struct buffer_head *bh[4];
88 	void *data;
89 };
90 
91 /* The b-tree down pointer from a dir entry */
92 
93 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
94 {
95   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
96   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
97 }
98 
99 /* The first dir entry in a dnode */
100 
101 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
102 {
103   return (void *) dnode->dirent;
104 }
105 
106 /* The end+1 of the dir entries */
107 
108 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
109 {
110   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)));
111   return (void *) dnode + le32_to_cpu(dnode->first_free);
112 }
113 
114 /* The dir entry after dir entry de */
115 
116 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
117 {
118   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)));
119   return (void *) de + le16_to_cpu(de->length);
120 }
121 
122 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
123 {
124 	return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
125 }
126 
127 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
128 {
129 	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));
130 }
131 
132 static unsigned ea_valuelen(struct extended_attribute *ea)
133 {
134 	return ea->valuelen_lo + 256 * ea->valuelen_hi;
135 }
136 
137 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
138 {
139 	return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
140 }
141 
142 static inline secno ea_sec(struct extended_attribute *ea)
143 {
144 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
145 }
146 
147 static inline secno ea_len(struct extended_attribute *ea)
148 {
149 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
150 }
151 
152 static inline char *ea_data(struct extended_attribute *ea)
153 {
154 	return (char *)((char *)ea + 5 + ea->namelen);
155 }
156 
157 static inline unsigned de_size(int namelen, secno down_ptr)
158 {
159 	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
160 }
161 
162 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
163 {
164 	int a;
165 	int n;
166 	if (!dst || !src) return;
167 	a = dst->down;
168 	n = dst->not_8x3;
169 	memcpy((char *)dst + 2, (char *)src + 2, 28);
170 	dst->down = a;
171 	dst->not_8x3 = n;
172 }
173 
174 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
175 {
176 	int i;
177 	if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
178 	if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
179 	for (i = 1; i < n; i++)
180 		if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
181 			return i + 1;
182 	return 0;
183 }
184 
185 /* alloc.c */
186 
187 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
188 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
189 int hpfs_alloc_if_possible(struct super_block *, secno);
190 void hpfs_free_sectors(struct super_block *, secno, unsigned);
191 int hpfs_check_free_dnodes(struct super_block *, int);
192 void hpfs_free_dnode(struct super_block *, secno);
193 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
194 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
195 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
196 
197 /* anode.c */
198 
199 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
200 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
201 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
202 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
203 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
204 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
205 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
206 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
207 
208 /* buffer.c */
209 
210 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
211 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
212 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
213 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
214 void hpfs_brelse4(struct quad_buffer_head *);
215 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
216 
217 /* dentry.c */
218 
219 extern const struct dentry_operations hpfs_dentry_operations;
220 
221 /* dir.c */
222 
223 struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
224 extern const struct file_operations hpfs_dir_ops;
225 
226 /* dnode.c */
227 
228 void hpfs_add_pos(struct inode *, loff_t *);
229 void hpfs_del_pos(struct inode *, loff_t *);
230 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
231 				const unsigned char *, unsigned, secno);
232 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
233 		    struct hpfs_dirent *);
234 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
235 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
236 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
237 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
238 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
239 			       const unsigned char *, unsigned, dnode_secno *,
240 			       struct quad_buffer_head *);
241 void hpfs_remove_dtree(struct super_block *, dnode_secno);
242 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
243 
244 /* ea.c */
245 
246 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
247 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
248 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
249 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
250 		 const char *, int);
251 
252 /* file.c */
253 
254 int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
255 extern const struct file_operations hpfs_file_ops;
256 extern const struct inode_operations hpfs_file_iops;
257 extern const struct address_space_operations hpfs_aops;
258 
259 /* inode.c */
260 
261 void hpfs_init_inode(struct inode *);
262 void hpfs_read_inode(struct inode *);
263 void hpfs_write_inode(struct inode *);
264 void hpfs_write_inode_nolock(struct inode *);
265 int hpfs_setattr(struct dentry *, struct iattr *);
266 void hpfs_write_if_changed(struct inode *);
267 void hpfs_evict_inode(struct inode *);
268 
269 /* map.c */
270 
271 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
272 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
273 unsigned char *hpfs_load_code_page(struct super_block *, secno);
274 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
275 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
276 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
277 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
278 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
279 
280 /* name.c */
281 
282 unsigned char hpfs_upcase(unsigned char *, unsigned char);
283 int hpfs_chk_name(const unsigned char *, unsigned *);
284 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
285 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
286 		       const unsigned char *, unsigned, int);
287 int hpfs_is_name_long(const unsigned char *, unsigned);
288 void hpfs_adjust_length(const unsigned char *, unsigned *);
289 
290 /* namei.c */
291 
292 extern const struct inode_operations hpfs_dir_iops;
293 extern const struct address_space_operations hpfs_symlink_aops;
294 
295 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
296 {
297 	return list_entry(inode, struct hpfs_inode_info, vfs_inode);
298 }
299 
300 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
301 {
302 	return sb->s_fs_info;
303 }
304 
305 /* super.c */
306 
307 __printf(2, 3)
308 void hpfs_error(struct super_block *, const char *, ...);
309 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
310 unsigned hpfs_count_one_bitmap(struct super_block *, secno);
311 
312 /*
313  * local time (HPFS) to GMT (Unix)
314  */
315 
316 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
317 {
318 	extern struct timezone sys_tz;
319 	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
320 }
321 
322 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
323 {
324 	extern struct timezone sys_tz;
325 	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
326 }
327 
328 /*
329  * Locking:
330  *
331  * hpfs_lock() locks the whole filesystem. It must be taken
332  * on any method called by the VFS.
333  *
334  * We don't do any per-file locking anymore, it is hard to
335  * review and HPFS is not performance-sensitive anyway.
336  */
337 static inline void hpfs_lock(struct super_block *s)
338 {
339 	struct hpfs_sb_info *sbi = hpfs_sb(s);
340 	mutex_lock(&sbi->hpfs_mutex);
341 }
342 
343 static inline void hpfs_unlock(struct super_block *s)
344 {
345 	struct hpfs_sb_info *sbi = hpfs_sb(s);
346 	mutex_unlock(&sbi->hpfs_mutex);
347 }
348 
349 static inline void hpfs_lock_assert(struct super_block *s)
350 {
351 	struct hpfs_sb_info *sbi = hpfs_sb(s);
352 	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
353 }
354