fs/hpfs/hpfs_fn.h

   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  EUCLEAN
  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         unsigned n_hotfixes;
  93         secno hotfix_from[256];
  94         secno hotfix_to[256];
  95 };
  96
  97 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
  98
  99 struct quad_buffer_head {
 100         struct buffer_head *bh[4];
 101         void *data;
 102 };
 103
 104 /* The b-tree down pointer from a dir entry */
 105
 106 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
 107 {
 108   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
 109   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
 110 }
 111
 112 /* The first dir entry in a dnode */
 113
 114 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
 115 {
 116   return (void *) dnode->dirent;
 117 }
 118
 119 /* The end+1 of the dir entries */
 120
 121 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
 122 {
 123   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)));
 124   return (void *) dnode + le32_to_cpu(dnode->first_free);
 125 }
 126
 127 /* The dir entry after dir entry de */
 128
 129 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
 130 {
 131   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)));
 132   return (void *) de + le16_to_cpu(de->length);
 133 }
 134
 135 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
 136 {
 137         return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
 138 }
 139
 140 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
 141 {
 142         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));
 143 }
 144
 145 static unsigned ea_valuelen(struct extended_attribute *ea)
 146 {
 147         return ea->valuelen_lo + 256 * ea->valuelen_hi;
 148 }
 149
 150 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
 151 {
 152         return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
 153 }
 154
 155 static inline secno ea_sec(struct extended_attribute *ea)
 156 {
 157         return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
 158 }
 159
 160 static inline secno ea_len(struct extended_attribute *ea)
 161 {
 162         return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
 163 }
 164
 165 static inline char *ea_data(struct extended_attribute *ea)
 166 {
 167         return (char *)((char *)ea + 5 + ea->namelen);
 168 }
 169
 170 static inline unsigned de_size(int namelen, secno down_ptr)
 171 {
 172         return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
 173 }
 174
 175 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
 176 {
 177         int a;
 178         int n;
 179         if (!dst || !src) return;
 180         a = dst->down;
 181         n = dst->not_8x3;
 182         memcpy((char *)dst + 2, (char *)src + 2, 28);
 183         dst->down = a;
 184         dst->not_8x3 = n;
 185 }
 186
 187 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
 188 {
 189         int i;
 190         if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
 191         if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
 192         for (i = 1; i < n; i++)
 193                 if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
 194                         return i + 1;
 195         return 0;
 196 }
 197
 198 /* alloc.c */
 199
 200 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
 201 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
 202 int hpfs_alloc_if_possible(struct super_block *, secno);
 203 void hpfs_free_sectors(struct super_block *, secno, unsigned);
 204 int hpfs_check_free_dnodes(struct super_block *, int);
 205 void hpfs_free_dnode(struct super_block *, secno);
 206 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
 207 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
 208 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
 209 int hpfs_trim_fs(struct super_block *, u64, u64, u64, unsigned *);
 210
 211 /* anode.c */
 212
 213 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
 214 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
 215 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
 216 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
 217 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
 218 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
 219 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
 220 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
 221
 222 /* buffer.c */
 223
 224 secno hpfs_search_hotfix_map(struct super_block *s, secno sec);
 225 unsigned hpfs_search_hotfix_map_for_range(struct super_block *s, secno sec, unsigned n);
 226 void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
 227 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
 228 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
 229 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
 230 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
 231 void hpfs_brelse4(struct quad_buffer_head *);
 232 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
 233
 234 /* dentry.c */
 235
 236 extern const struct dentry_operations hpfs_dentry_operations;
 237
 238 /* dir.c */
 239
 240 struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
 241 extern const struct file_operations hpfs_dir_ops;
 242
 243 /* dnode.c */
 244
 245 int hpfs_add_pos(struct inode *, loff_t *);
 246 void hpfs_del_pos(struct inode *, loff_t *);
 247 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
 248                                 const unsigned char *, unsigned, secno);
 249 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
 250                     struct hpfs_dirent *);
 251 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
 252 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
 253 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
 254 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
 255 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
 256                                const unsigned char *, unsigned, dnode_secno *,
 257                                struct quad_buffer_head *);
 258 void hpfs_remove_dtree(struct super_block *, dnode_secno);
 259 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
 260
 261 /* ea.c */
 262
 263 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
 264 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
 265 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
 266 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
 267                  const char *, int);
 268
 269 /* file.c */
 270
 271 int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
 272 void hpfs_truncate(struct inode *);
 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 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
 290 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
 291 void hpfs_prefetch_bitmap(struct super_block *, unsigned);
 292 unsigned char *hpfs_load_code_page(struct super_block *, secno);
 293 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
 294 void hpfs_load_hotfix_map(struct super_block *s, struct hpfs_spare_block *spareblock);
 295 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
 296 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
 297 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
 298 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
 299
 300 /* name.c */
 301
 302 unsigned char hpfs_upcase(unsigned char *, unsigned char);
 303 int hpfs_chk_name(const unsigned char *, unsigned *);
 304 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
 305 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
 306                        const unsigned char *, unsigned, int);
 307 int hpfs_is_name_long(const unsigned char *, unsigned);
 308 void hpfs_adjust_length(const unsigned char *, unsigned *);
 309
 310 /* namei.c */
 311
 312 extern const struct inode_operations hpfs_dir_iops;
 313 extern const struct address_space_operations hpfs_symlink_aops;
 314
 315 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
 316 {
 317         return container_of(inode, struct hpfs_inode_info, vfs_inode);
 318 }
 319
 320 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
 321 {
 322         return sb->s_fs_info;
 323 }
 324
 325 /* super.c */
 326
 327 __printf(2, 3)
 328 void hpfs_error(struct super_block *, const char *, ...);
 329 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
 330 unsigned hpfs_get_free_dnodes(struct super_block *);
 331 long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg);
 332
 333 /*
 334  * local time (HPFS) to GMT (Unix)
 335  */
 336
 337 static inline time64_t local_to_gmt(struct super_block *s, time32_t t)
 338 {
 339         extern struct timezone sys_tz;
 340         return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
 341 }
 342
 343 static inline time32_t gmt_to_local(struct super_block *s, time64_t t)
 344 {
 345         extern struct timezone sys_tz;
 346         t = t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
 347
 348         return clamp_t(time64_t, t, 0, U32_MAX);
 349 }
 350
 351 static inline time32_t local_get_seconds(struct super_block *s)
 352 {
 353         return gmt_to_local(s, ktime_get_real_seconds());
 354 }
 355
 356 /*
 357  * Locking:
 358  *
 359  * hpfs_lock() locks the whole filesystem. It must be taken
 360  * on any method called by the VFS.
 361  *
 362  * We don't do any per-file locking anymore, it is hard to
 363  * review and HPFS is not performance-sensitive anyway.
 364  */
 365 static inline void hpfs_lock(struct super_block *s)
 366 {
 367         struct hpfs_sb_info *sbi = hpfs_sb(s);
 368         mutex_lock(&sbi->hpfs_mutex);
 369 }
 370
 371 static inline void hpfs_unlock(struct super_block *s)
 372 {
 373         struct hpfs_sb_info *sbi = hpfs_sb(s);
 374         mutex_unlock(&sbi->hpfs_mutex);
 375 }
 376
 377 static inline void hpfs_lock_assert(struct super_block *s)
 378 {
 379         struct hpfs_sb_info *sbi = hpfs_sb(s);
 380         WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
 381 }