xref: /linux/fs/hpfs/hpfs_fn.h (revision 93df8a1ed6231727c5db94a80b1a6bd5ee67cec3)
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 <linux/sched.h>
22 #include <linux/blkdev.h>
23 #include <asm/unaligned.h>
24 
25 #include "hpfs.h"
26 
27 #define EIOERROR  EIO
28 #define EFSERROR  EPERM
29 #define EMEMERROR ENOMEM
30 
31 #define ANODE_ALLOC_FWD	512
32 #define FNODE_ALLOC_FWD	0
33 #define ALLOC_FWD_MIN	16
34 #define ALLOC_FWD_MAX	128
35 #define ALLOC_M		1
36 #define FNODE_RD_AHEAD	16
37 #define ANODE_RD_AHEAD	0
38 #define DNODE_RD_AHEAD	72
39 #define COUNT_RD_AHEAD	62
40 
41 #define FREE_DNODES_ADD	58
42 #define FREE_DNODES_DEL	29
43 
44 #define CHKCOND(x,y) if (!(x)) printk y
45 
46 struct hpfs_inode_info {
47 	loff_t mmu_private;
48 	ino_t i_parent_dir;	/* (directories) gives fnode of parent dir */
49 	unsigned i_dno;		/* (directories) root dnode */
50 	unsigned i_dpos;	/* (directories) temp for readdir */
51 	unsigned i_dsubdno;	/* (directories) temp for readdir */
52 	unsigned i_file_sec;	/* (files) minimalist cache of alloc info */
53 	unsigned i_disk_sec;	/* (files) minimalist cache of alloc info */
54 	unsigned i_n_secs;	/* (files) minimalist cache of alloc info */
55 	unsigned i_ea_size;	/* size of extended attributes */
56 	unsigned i_ea_mode : 1;	/* file's permission is stored in ea */
57 	unsigned i_ea_uid : 1;	/* file's uid is stored in ea */
58 	unsigned i_ea_gid : 1;	/* file's gid is stored in ea */
59 	unsigned i_dirty : 1;
60 	loff_t **i_rddir_off;
61 	struct inode vfs_inode;
62 };
63 
64 struct hpfs_sb_info {
65 	struct mutex hpfs_mutex;	/* global hpfs lock */
66 	ino_t sb_root;			/* inode number of root dir */
67 	unsigned sb_fs_size;		/* file system size, sectors */
68 	unsigned sb_bitmaps;		/* sector number of bitmap list */
69 	unsigned sb_dirband_start;	/* directory band start sector */
70 	unsigned sb_dirband_size;	/* directory band size, dnodes */
71 	unsigned sb_dmap;		/* sector number of dnode bit map */
72 	unsigned sb_n_free;		/* free blocks for statfs, or -1 */
73 	unsigned sb_n_free_dnodes;	/* free dnodes for statfs, or -1 */
74 	kuid_t sb_uid;			/* uid from mount options */
75 	kgid_t sb_gid;			/* gid from mount options */
76 	umode_t sb_mode;		/* mode from mount options */
77 	unsigned sb_eas : 2;		/* eas: 0-ignore, 1-ro, 2-rw */
78 	unsigned sb_err : 2;		/* on errs: 0-cont, 1-ro, 2-panic */
79 	unsigned sb_chk : 2;		/* checks: 0-no, 1-normal, 2-strict */
80 	unsigned sb_lowercase : 1;	/* downcase filenames hackery */
81 	unsigned sb_was_error : 1;	/* there was an error, set dirty flag */
82 	unsigned sb_chkdsk : 2;		/* chkdsk: 0-no, 1-on errs, 2-allways */
83 	unsigned char *sb_cp_table;	/* code page tables: */
84 					/* 	128 bytes uppercasing table & */
85 					/*	128 bytes lowercasing table */
86 	__le32 *sb_bmp_dir;		/* main bitmap directory */
87 	unsigned sb_c_bitmap;		/* current bitmap */
88 	unsigned sb_max_fwd_alloc;	/* max forwad allocation */
89 	int sb_timeshift;
90 	struct rcu_head rcu;
91 };
92 
93 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
94 
95 struct quad_buffer_head {
96 	struct buffer_head *bh[4];
97 	void *data;
98 };
99 
100 /* The b-tree down pointer from a dir entry */
101 
102 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
103 {
104   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
105   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
106 }
107 
108 /* The first dir entry in a dnode */
109 
110 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
111 {
112   return (void *) dnode->dirent;
113 }
114 
115 /* The end+1 of the dir entries */
116 
117 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
118 {
119   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)));
120   return (void *) dnode + le32_to_cpu(dnode->first_free);
121 }
122 
123 /* The dir entry after dir entry de */
124 
125 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
126 {
127   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)));
128   return (void *) de + le16_to_cpu(de->length);
129 }
130 
131 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
132 {
133 	return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
134 }
135 
136 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
137 {
138 	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));
139 }
140 
141 static unsigned ea_valuelen(struct extended_attribute *ea)
142 {
143 	return ea->valuelen_lo + 256 * ea->valuelen_hi;
144 }
145 
146 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
147 {
148 	return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
149 }
150 
151 static inline secno ea_sec(struct extended_attribute *ea)
152 {
153 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
154 }
155 
156 static inline secno ea_len(struct extended_attribute *ea)
157 {
158 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
159 }
160 
161 static inline char *ea_data(struct extended_attribute *ea)
162 {
163 	return (char *)((char *)ea + 5 + ea->namelen);
164 }
165 
166 static inline unsigned de_size(int namelen, secno down_ptr)
167 {
168 	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
169 }
170 
171 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
172 {
173 	int a;
174 	int n;
175 	if (!dst || !src) return;
176 	a = dst->down;
177 	n = dst->not_8x3;
178 	memcpy((char *)dst + 2, (char *)src + 2, 28);
179 	dst->down = a;
180 	dst->not_8x3 = n;
181 }
182 
183 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
184 {
185 	int i;
186 	if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
187 	if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
188 	for (i = 1; i < n; i++)
189 		if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
190 			return i + 1;
191 	return 0;
192 }
193 
194 /* alloc.c */
195 
196 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
197 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
198 int hpfs_alloc_if_possible(struct super_block *, secno);
199 void hpfs_free_sectors(struct super_block *, secno, unsigned);
200 int hpfs_check_free_dnodes(struct super_block *, int);
201 void hpfs_free_dnode(struct super_block *, secno);
202 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
203 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
204 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
205 int hpfs_trim_fs(struct super_block *, u64, u64, u64, unsigned *);
206 
207 /* anode.c */
208 
209 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
210 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
211 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
212 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
213 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
214 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
215 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
216 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
217 
218 /* buffer.c */
219 
220 void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
221 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
222 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
223 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
224 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
225 void hpfs_brelse4(struct quad_buffer_head *);
226 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
227 
228 /* dentry.c */
229 
230 extern const struct dentry_operations hpfs_dentry_operations;
231 
232 /* dir.c */
233 
234 struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
235 extern const struct file_operations hpfs_dir_ops;
236 
237 /* dnode.c */
238 
239 void hpfs_add_pos(struct inode *, loff_t *);
240 void hpfs_del_pos(struct inode *, loff_t *);
241 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
242 				const unsigned char *, unsigned, secno);
243 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
244 		    struct hpfs_dirent *);
245 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
246 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
247 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
248 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
249 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
250 			       const unsigned char *, unsigned, dnode_secno *,
251 			       struct quad_buffer_head *);
252 void hpfs_remove_dtree(struct super_block *, dnode_secno);
253 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
254 
255 /* ea.c */
256 
257 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
258 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
259 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
260 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
261 		 const char *, int);
262 
263 /* file.c */
264 
265 int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
266 void hpfs_truncate(struct inode *);
267 extern const struct file_operations hpfs_file_ops;
268 extern const struct inode_operations hpfs_file_iops;
269 extern const struct address_space_operations hpfs_aops;
270 
271 /* inode.c */
272 
273 void hpfs_init_inode(struct inode *);
274 void hpfs_read_inode(struct inode *);
275 void hpfs_write_inode(struct inode *);
276 void hpfs_write_inode_nolock(struct inode *);
277 int hpfs_setattr(struct dentry *, struct iattr *);
278 void hpfs_write_if_changed(struct inode *);
279 void hpfs_evict_inode(struct inode *);
280 
281 /* map.c */
282 
283 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
284 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
285 void hpfs_prefetch_bitmap(struct super_block *, unsigned);
286 unsigned char *hpfs_load_code_page(struct super_block *, secno);
287 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
288 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
289 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
290 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
291 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
292 
293 /* name.c */
294 
295 unsigned char hpfs_upcase(unsigned char *, unsigned char);
296 int hpfs_chk_name(const unsigned char *, unsigned *);
297 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
298 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
299 		       const unsigned char *, unsigned, int);
300 int hpfs_is_name_long(const unsigned char *, unsigned);
301 void hpfs_adjust_length(const unsigned char *, unsigned *);
302 
303 /* namei.c */
304 
305 extern const struct inode_operations hpfs_dir_iops;
306 extern const struct address_space_operations hpfs_symlink_aops;
307 
308 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
309 {
310 	return container_of(inode, struct hpfs_inode_info, vfs_inode);
311 }
312 
313 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
314 {
315 	return sb->s_fs_info;
316 }
317 
318 /* super.c */
319 
320 __printf(2, 3)
321 void hpfs_error(struct super_block *, const char *, ...);
322 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
323 unsigned hpfs_get_free_dnodes(struct super_block *);
324 long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg);
325 
326 /*
327  * local time (HPFS) to GMT (Unix)
328  */
329 
330 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
331 {
332 	extern struct timezone sys_tz;
333 	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
334 }
335 
336 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
337 {
338 	extern struct timezone sys_tz;
339 	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
340 }
341 
342 /*
343  * Locking:
344  *
345  * hpfs_lock() locks the whole filesystem. It must be taken
346  * on any method called by the VFS.
347  *
348  * We don't do any per-file locking anymore, it is hard to
349  * review and HPFS is not performance-sensitive anyway.
350  */
351 static inline void hpfs_lock(struct super_block *s)
352 {
353 	struct hpfs_sb_info *sbi = hpfs_sb(s);
354 	mutex_lock(&sbi->hpfs_mutex);
355 }
356 
357 static inline void hpfs_unlock(struct super_block *s)
358 {
359 	struct hpfs_sb_info *sbi = hpfs_sb(s);
360 	mutex_unlock(&sbi->hpfs_mutex);
361 }
362 
363 static inline void hpfs_lock_assert(struct super_block *s)
364 {
365 	struct hpfs_sb_info *sbi = hpfs_sb(s);
366 	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
367 }
368