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  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 }