xref: /openbmc/linux/fs/hpfs/hpfs_fn.h (revision 2359ccdd)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /*
3  *  linux/fs/hpfs/hpfs_fn.h
4  *
5  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
6  *
7  *  function headers
8  */
9 
10 //#define DBG
11 //#define DEBUG_LOCKS
12 #ifdef pr_fmt
13 #undef pr_fmt
14 #endif
15 
16 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
17 
18 #include <linux/mutex.h>
19 #include <linux/pagemap.h>
20 #include <linux/buffer_head.h>
21 #include <linux/slab.h>
22 #include <linux/sched/signal.h>
23 #include <linux/blkdev.h>
24 #include <asm/unaligned.h>
25 
26 #include "hpfs.h"
27 
28 #define EIOERROR  EIO
29 #define EFSERROR  EPERM
30 #define EMEMERROR ENOMEM
31 
32 #define ANODE_ALLOC_FWD	512
33 #define FNODE_ALLOC_FWD	0
34 #define ALLOC_FWD_MIN	16
35 #define ALLOC_FWD_MAX	128
36 #define ALLOC_M		1
37 #define FNODE_RD_AHEAD	16
38 #define ANODE_RD_AHEAD	0
39 #define DNODE_RD_AHEAD	72
40 #define COUNT_RD_AHEAD	62
41 
42 #define FREE_DNODES_ADD	58
43 #define FREE_DNODES_DEL	29
44 
45 #define CHKCOND(x,y) if (!(x)) printk y
46 
47 struct hpfs_inode_info {
48 	loff_t mmu_private;
49 	ino_t i_parent_dir;	/* (directories) gives fnode of parent dir */
50 	unsigned i_dno;		/* (directories) root dnode */
51 	unsigned i_dpos;	/* (directories) temp for readdir */
52 	unsigned i_dsubdno;	/* (directories) temp for readdir */
53 	unsigned i_file_sec;	/* (files) minimalist cache of alloc info */
54 	unsigned i_disk_sec;	/* (files) minimalist cache of alloc info */
55 	unsigned i_n_secs;	/* (files) minimalist cache of alloc info */
56 	unsigned i_ea_size;	/* size of extended attributes */
57 	unsigned i_ea_mode : 1;	/* file's permission is stored in ea */
58 	unsigned i_ea_uid : 1;	/* file's uid is stored in ea */
59 	unsigned i_ea_gid : 1;	/* file's gid is stored in ea */
60 	unsigned i_dirty : 1;
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 	kuid_t sb_uid;			/* uid from mount options */
76 	kgid_t sb_gid;			/* gid from mount options */
77 	umode_t sb_mode;		/* mode from mount options */
78 	unsigned sb_eas : 2;		/* eas: 0-ignore, 1-ro, 2-rw */
79 	unsigned sb_err : 2;		/* on errs: 0-cont, 1-ro, 2-panic */
80 	unsigned sb_chk : 2;		/* checks: 0-no, 1-normal, 2-strict */
81 	unsigned sb_lowercase : 1;	/* downcase filenames hackery */
82 	unsigned sb_was_error : 1;	/* there was an error, set dirty flag */
83 	unsigned sb_chkdsk : 2;		/* chkdsk: 0-no, 1-on errs, 2-allways */
84 	unsigned char *sb_cp_table;	/* code page tables: */
85 					/* 	128 bytes uppercasing table & */
86 					/*	128 bytes lowercasing table */
87 	__le32 *sb_bmp_dir;		/* main bitmap directory */
88 	unsigned sb_c_bitmap;		/* current bitmap */
89 	unsigned sb_max_fwd_alloc;	/* max forwad allocation */
90 	int sb_timeshift;
91 	struct rcu_head rcu;
92 
93 	unsigned n_hotfixes;
94 	secno hotfix_from[256];
95 	secno hotfix_to[256];
96 };
97 
98 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
99 
100 struct quad_buffer_head {
101 	struct buffer_head *bh[4];
102 	void *data;
103 };
104 
105 /* The b-tree down pointer from a dir entry */
106 
107 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
108 {
109   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
110   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
111 }
112 
113 /* The first dir entry in a dnode */
114 
115 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
116 {
117   return (void *) dnode->dirent;
118 }
119 
120 /* The end+1 of the dir entries */
121 
122 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
123 {
124   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)));
125   return (void *) dnode + le32_to_cpu(dnode->first_free);
126 }
127 
128 /* The dir entry after dir entry de */
129 
130 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
131 {
132   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)));
133   return (void *) de + le16_to_cpu(de->length);
134 }
135 
136 static inline struct extended_attribute *fnode_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));
139 }
140 
141 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
142 {
143 	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));
144 }
145 
146 static unsigned ea_valuelen(struct extended_attribute *ea)
147 {
148 	return ea->valuelen_lo + 256 * ea->valuelen_hi;
149 }
150 
151 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
152 {
153 	return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
154 }
155 
156 static inline secno ea_sec(struct extended_attribute *ea)
157 {
158 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
159 }
160 
161 static inline secno ea_len(struct extended_attribute *ea)
162 {
163 	return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
164 }
165 
166 static inline char *ea_data(struct extended_attribute *ea)
167 {
168 	return (char *)((char *)ea + 5 + ea->namelen);
169 }
170 
171 static inline unsigned de_size(int namelen, secno down_ptr)
172 {
173 	return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
174 }
175 
176 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
177 {
178 	int a;
179 	int n;
180 	if (!dst || !src) return;
181 	a = dst->down;
182 	n = dst->not_8x3;
183 	memcpy((char *)dst + 2, (char *)src + 2, 28);
184 	dst->down = a;
185 	dst->not_8x3 = n;
186 }
187 
188 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
189 {
190 	int i;
191 	if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
192 	if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
193 	for (i = 1; i < n; i++)
194 		if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
195 			return i + 1;
196 	return 0;
197 }
198 
199 /* alloc.c */
200 
201 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
202 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
203 int hpfs_alloc_if_possible(struct super_block *, secno);
204 void hpfs_free_sectors(struct super_block *, secno, unsigned);
205 int hpfs_check_free_dnodes(struct super_block *, int);
206 void hpfs_free_dnode(struct super_block *, secno);
207 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
208 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
209 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
210 int hpfs_trim_fs(struct super_block *, u64, u64, u64, unsigned *);
211 
212 /* anode.c */
213 
214 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
215 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
216 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
217 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
218 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
219 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
220 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
221 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
222 
223 /* buffer.c */
224 
225 secno hpfs_search_hotfix_map(struct super_block *s, secno sec);
226 unsigned hpfs_search_hotfix_map_for_range(struct super_block *s, secno sec, unsigned n);
227 void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
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 *, unsigned int);
242 extern const struct file_operations hpfs_dir_ops;
243 
244 /* dnode.c */
245 
246 int 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 *);
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 *, loff_t, loff_t, int);
273 void hpfs_truncate(struct inode *);
274 extern const struct file_operations hpfs_file_ops;
275 extern const struct inode_operations hpfs_file_iops;
276 extern const struct address_space_operations hpfs_aops;
277 
278 /* inode.c */
279 
280 void hpfs_init_inode(struct inode *);
281 void hpfs_read_inode(struct inode *);
282 void hpfs_write_inode(struct inode *);
283 void hpfs_write_inode_nolock(struct inode *);
284 int hpfs_setattr(struct dentry *, struct iattr *);
285 void hpfs_write_if_changed(struct inode *);
286 void hpfs_evict_inode(struct inode *);
287 
288 /* map.c */
289 
290 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
291 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
292 void hpfs_prefetch_bitmap(struct super_block *, unsigned);
293 unsigned char *hpfs_load_code_page(struct super_block *, secno);
294 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
295 void hpfs_load_hotfix_map(struct super_block *s, struct hpfs_spare_block *spareblock);
296 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
297 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
298 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
299 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
300 
301 /* name.c */
302 
303 unsigned char hpfs_upcase(unsigned char *, unsigned char);
304 int hpfs_chk_name(const unsigned char *, unsigned *);
305 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
306 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
307 		       const unsigned char *, unsigned, int);
308 int hpfs_is_name_long(const unsigned char *, unsigned);
309 void hpfs_adjust_length(const unsigned char *, unsigned *);
310 
311 /* namei.c */
312 
313 extern const struct inode_operations hpfs_dir_iops;
314 extern const struct address_space_operations hpfs_symlink_aops;
315 
316 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
317 {
318 	return container_of(inode, struct hpfs_inode_info, vfs_inode);
319 }
320 
321 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
322 {
323 	return sb->s_fs_info;
324 }
325 
326 /* super.c */
327 
328 __printf(2, 3)
329 void hpfs_error(struct super_block *, const char *, ...);
330 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
331 unsigned hpfs_get_free_dnodes(struct super_block *);
332 long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg);
333 
334 /*
335  * local time (HPFS) to GMT (Unix)
336  */
337 
338 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
339 {
340 	extern struct timezone sys_tz;
341 	return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
342 }
343 
344 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
345 {
346 	extern struct timezone sys_tz;
347 	return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
348 }
349 
350 /*
351  * Locking:
352  *
353  * hpfs_lock() locks the whole filesystem. It must be taken
354  * on any method called by the VFS.
355  *
356  * We don't do any per-file locking anymore, it is hard to
357  * review and HPFS is not performance-sensitive anyway.
358  */
359 static inline void hpfs_lock(struct super_block *s)
360 {
361 	struct hpfs_sb_info *sbi = hpfs_sb(s);
362 	mutex_lock(&sbi->hpfs_mutex);
363 }
364 
365 static inline void hpfs_unlock(struct super_block *s)
366 {
367 	struct hpfs_sb_info *sbi = hpfs_sb(s);
368 	mutex_unlock(&sbi->hpfs_mutex);
369 }
370 
371 static inline void hpfs_lock_assert(struct super_block *s)
372 {
373 	struct hpfs_sb_info *sbi = hpfs_sb(s);
374 	WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
375 }
376