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