fs/hpfs/hpfs_fn.h

   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 #ifdef DBG
  39 #define PRINTK(x) printk x
  40 #else
  41 #undef PRINTK
  42 #define PRINTK(x)
  43 #endif
  44
  45 struct hpfs_inode_info {
  46         loff_t mmu_private;
  47         ino_t i_parent_dir;     /* (directories) gives fnode of parent dir */
  48         unsigned i_dno;         /* (directories) root dnode */
  49         unsigned i_dpos;        /* (directories) temp for readdir */
  50         unsigned i_dsubdno;     /* (directories) temp for readdir */
  51         unsigned i_file_sec;    /* (files) minimalist cache of alloc info */
  52         unsigned i_disk_sec;    /* (files) minimalist cache of alloc info */
  53         unsigned i_n_secs;      /* (files) minimalist cache of alloc info */
  54         unsigned i_ea_size;     /* size of extended attributes */
  55         unsigned i_ea_mode : 1; /* file's permission is stored in ea */
  56         unsigned i_ea_uid : 1;  /* file's uid is stored in ea */
  57         unsigned i_ea_gid : 1;  /* file's gid is stored in ea */
  58         unsigned i_dirty : 1;
  59         loff_t **i_rddir_off;
  60         struct inode vfs_inode;
  61 };
  62
  63 struct hpfs_sb_info {
  64         struct mutex hpfs_mutex;        /* global hpfs lock */
  65         ino_t sb_root;                  /* inode number of root dir */
  66         unsigned sb_fs_size;            /* file system size, sectors */
  67         unsigned sb_bitmaps;            /* sector number of bitmap list */
  68         unsigned sb_dirband_start;      /* directory band start sector */
  69         unsigned sb_dirband_size;       /* directory band size, dnodes */
  70         unsigned sb_dmap;               /* sector number of dnode bit map */
  71         unsigned sb_n_free;             /* free blocks for statfs, or -1 */
  72         unsigned sb_n_free_dnodes;      /* free dnodes for statfs, or -1 */
  73         uid_t sb_uid;                   /* uid from mount options */
  74         gid_t sb_gid;                   /* gid from mount options */
  75         umode_t sb_mode;                /* mode from mount options */
  76         unsigned sb_eas : 2;            /* eas: 0-ignore, 1-ro, 2-rw */
  77         unsigned sb_err : 2;            /* on errs: 0-cont, 1-ro, 2-panic */
  78         unsigned sb_chk : 2;            /* checks: 0-no, 1-normal, 2-strict */
  79         unsigned sb_lowercase : 1;      /* downcase filenames hackery */
  80         unsigned sb_was_error : 1;      /* there was an error, set dirty flag */
  81         unsigned sb_chkdsk : 2;         /* chkdsk: 0-no, 1-on errs, 2-allways */
  82         unsigned char *sb_cp_table;     /* code page tables: */
  83                                         /*      128 bytes uppercasing table & */
  84                                         /*      128 bytes lowercasing table */
  85         unsigned *sb_bmp_dir;           /* main bitmap directory */
  86         unsigned sb_c_bitmap;           /* current bitmap */
  87         unsigned sb_max_fwd_alloc;      /* max forwad allocation */
  88         int sb_timeshift;
  89 };
  90
  91 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
  92
  93 struct quad_buffer_head {
  94         struct buffer_head *bh[4];
  95         void *data;
  96 };
  97
  98 /* The b-tree down pointer from a dir entry */
  99
 100 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
 101 {
 102   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
 103   return le32_to_cpu(*(dnode_secno *) ((void *) de + le16_to_cpu(de->length) - 4));
 104 }
 105
 106 /* The first dir entry in a dnode */
 107
 108 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
 109 {
 110   return (void *) dnode->dirent;
 111 }
 112
 113 /* The end+1 of the dir entries */
 114
 115 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
 116 {
 117   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)));
 118   return (void *) dnode + le32_to_cpu(dnode->first_free);
 119 }
 120
 121 /* The dir entry after dir entry de */
 122
 123 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
 124 {
 125   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)));
 126   return (void *) de + le16_to_cpu(de->length);
 127 }
 128
 129 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
 130 {
 131         return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
 132 }
 133
 134 static inline struct extended_attribute *fnode_end_ea(struct fnode *fnode)
 135 {
 136         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));
 137 }
 138
 139 static unsigned ea_valuelen(struct extended_attribute *ea)
 140 {
 141         return ea->valuelen_lo + 256 * ea->valuelen_hi;
 142 }
 143
 144 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
 145 {
 146         return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
 147 }
 148
 149 static inline secno ea_sec(struct extended_attribute *ea)
 150 {
 151         return le32_to_cpu(get_unaligned((secno *)((char *)ea + 9 + ea->namelen)));
 152 }
 153
 154 static inline secno ea_len(struct extended_attribute *ea)
 155 {
 156         return le32_to_cpu(get_unaligned((secno *)((char *)ea + 5 + ea->namelen)));
 157 }
 158
 159 static inline char *ea_data(struct extended_attribute *ea)
 160 {
 161         return (char *)((char *)ea + 5 + ea->namelen);
 162 }
 163
 164 static inline unsigned de_size(int namelen, secno down_ptr)
 165 {
 166         return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
 167 }
 168
 169 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
 170 {
 171         int a;
 172         int n;
 173         if (!dst || !src) return;
 174         a = dst->down;
 175         n = dst->not_8x3;
 176         memcpy((char *)dst + 2, (char *)src + 2, 28);
 177         dst->down = a;
 178         dst->not_8x3 = n;
 179 }
 180
 181 static inline unsigned tstbits(u32 *bmp, unsigned b, unsigned n)
 182 {
 183         int i;
 184         if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
 185         if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
 186         for (i = 1; i < n; i++)
 187                 if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
 188                         return i + 1;
 189         return 0;
 190 }
 191
 192 /* alloc.c */
 193
 194 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
 195 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
 196 int hpfs_alloc_if_possible(struct super_block *, secno);
 197 void hpfs_free_sectors(struct super_block *, secno, unsigned);
 198 int hpfs_check_free_dnodes(struct super_block *, int);
 199 void hpfs_free_dnode(struct super_block *, secno);
 200 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
 201 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
 202 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
 203
 204 /* anode.c */
 205
 206 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
 207 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
 208 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
 209 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
 210 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
 211 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
 212 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
 213 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
 214
 215 /* buffer.c */
 216
 217 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
 218 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
 219 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
 220 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
 221 void hpfs_brelse4(struct quad_buffer_head *);
 222 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
 223
 224 /* dentry.c */
 225
 226 extern const struct dentry_operations hpfs_dentry_operations;
 227
 228 /* dir.c */
 229
 230 struct dentry *hpfs_lookup(struct inode *, struct dentry *, struct nameidata *);
 231 extern const struct file_operations hpfs_dir_ops;
 232
 233 /* dnode.c */
 234
 235 void hpfs_add_pos(struct inode *, loff_t *);
 236 void hpfs_del_pos(struct inode *, loff_t *);
 237 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
 238                                 const unsigned char *, unsigned, secno);
 239 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
 240                     struct hpfs_dirent *);
 241 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
 242 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
 243 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
 244 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
 245 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
 246                                const unsigned char *, unsigned, dnode_secno *,
 247                                struct quad_buffer_head *);
 248 void hpfs_remove_dtree(struct super_block *, dnode_secno);
 249 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
 250
 251 /* ea.c */
 252
 253 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
 254 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
 255 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
 256 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
 257                  const char *, int);
 258
 259 /* file.c */
 260
 261 int hpfs_file_fsync(struct file *, int);
 262 extern const struct file_operations hpfs_file_ops;
 263 extern const struct inode_operations hpfs_file_iops;
 264 extern const struct address_space_operations hpfs_aops;
 265
 266 /* inode.c */
 267
 268 void hpfs_init_inode(struct inode *);
 269 void hpfs_read_inode(struct inode *);
 270 void hpfs_write_inode(struct inode *);
 271 void hpfs_write_inode_nolock(struct inode *);
 272 int hpfs_setattr(struct dentry *, struct iattr *);
 273 void hpfs_write_if_changed(struct inode *);
 274 void hpfs_evict_inode(struct inode *);
 275
 276 /* map.c */
 277
 278 unsigned *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
 279 unsigned *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
 280 unsigned char *hpfs_load_code_page(struct super_block *, secno);
 281 secno *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
 282 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
 283 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
 284 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
 285 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
 286
 287 /* name.c */
 288
 289 unsigned char hpfs_upcase(unsigned char *, unsigned char);
 290 int hpfs_chk_name(const unsigned char *, unsigned *);
 291 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
 292 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
 293                        const unsigned char *, unsigned, int);
 294 int hpfs_is_name_long(const unsigned char *, unsigned);
 295 void hpfs_adjust_length(const unsigned char *, unsigned *);
 296
 297 /* namei.c */
 298
 299 extern const struct inode_operations hpfs_dir_iops;
 300 extern const struct address_space_operations hpfs_symlink_aops;
 301
 302 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
 303 {
 304         return list_entry(inode, struct hpfs_inode_info, vfs_inode);
 305 }
 306
 307 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
 308 {
 309         return sb->s_fs_info;
 310 }
 311
 312 /* super.c */
 313
 314 void hpfs_error(struct super_block *, const char *, ...)
 315         __attribute__((format (printf, 2, 3)));
 316 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
 317 unsigned hpfs_count_one_bitmap(struct super_block *, secno);
 318
 319 /*
 320  * local time (HPFS) to GMT (Unix)
 321  */
 322
 323 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
 324 {
 325         extern struct timezone sys_tz;
 326         return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
 327 }
 328
 329 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
 330 {
 331         extern struct timezone sys_tz;
 332         return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
 333 }
 334
 335 /*
 336  * Locking:
 337  *
 338  * hpfs_lock() locks the whole filesystem. It must be taken
 339  * on any method called by the VFS.
 340  *
 341  * We don't do any per-file locking anymore, it is hard to
 342  * review and HPFS is not performance-sensitive anyway.
 343  */
 344 static inline void hpfs_lock(struct super_block *s)
 345 {
 346         struct hpfs_sb_info *sbi = hpfs_sb(s);
 347         mutex_lock(&sbi->hpfs_mutex);
 348 }
 349
 350 static inline void hpfs_unlock(struct super_block *s)
 351 {
 352         struct hpfs_sb_info *sbi = hpfs_sb(s);
 353         mutex_unlock(&sbi->hpfs_mutex);
 354 }
 355
 356 static inline void hpfs_lock_assert(struct super_block *s)
 357 {
 358         struct hpfs_sb_info *sbi = hpfs_sb(s);
 359         WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
 360 }