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  0
  31 #define DNODE_RD_AHEAD  72
  32 #define COUNT_RD_AHEAD  62
  33
  34 #define FREE_DNODES_ADD 58
  35 #define FREE_DNODES_DEL 29
  36
  37 #define CHKCOND(x,y) if (!(x)) printk y
  38
  39 struct hpfs_inode_info {
  40         loff_t mmu_private;
  41         ino_t i_parent_dir;     /* (directories) gives fnode of parent dir */
  42         unsigned i_dno;         /* (directories) root dnode */
  43         unsigned i_dpos;        /* (directories) temp for readdir */
  44         unsigned i_dsubdno;     /* (directories) temp for readdir */
  45         unsigned i_file_sec;    /* (files) minimalist cache of alloc info */
  46         unsigned i_disk_sec;    /* (files) minimalist cache of alloc info */
  47         unsigned i_n_secs;      /* (files) minimalist cache of alloc info */
  48         unsigned i_ea_size;     /* size of extended attributes */
  49         unsigned i_ea_mode : 1; /* file's permission is stored in ea */
  50         unsigned i_ea_uid : 1;  /* file's uid is stored in ea */
  51         unsigned i_ea_gid : 1;  /* file's gid is stored in ea */
  52         unsigned i_dirty : 1;
  53         loff_t **i_rddir_off;
  54         struct inode vfs_inode;
  55 };
  56
  57 struct hpfs_sb_info {
  58         struct mutex hpfs_mutex;        /* global hpfs lock */
  59         ino_t sb_root;                  /* inode number of root dir */
  60         unsigned sb_fs_size;            /* file system size, sectors */
  61         unsigned sb_bitmaps;            /* sector number of bitmap list */
  62         unsigned sb_dirband_start;      /* directory band start sector */
  63         unsigned sb_dirband_size;       /* directory band size, dnodes */
  64         unsigned sb_dmap;               /* sector number of dnode bit map */
  65         unsigned sb_n_free;             /* free blocks for statfs, or -1 */
  66         unsigned sb_n_free_dnodes;      /* free dnodes for statfs, or -1 */
  67         kuid_t sb_uid;                  /* uid from mount options */
  68         kgid_t sb_gid;                  /* gid from mount options */
  69         umode_t sb_mode;                /* mode from mount options */
  70         unsigned sb_eas : 2;            /* eas: 0-ignore, 1-ro, 2-rw */
  71         unsigned sb_err : 2;            /* on errs: 0-cont, 1-ro, 2-panic */
  72         unsigned sb_chk : 2;            /* checks: 0-no, 1-normal, 2-strict */
  73         unsigned sb_lowercase : 1;      /* downcase filenames hackery */
  74         unsigned sb_was_error : 1;      /* there was an error, set dirty flag */
  75         unsigned sb_chkdsk : 2;         /* chkdsk: 0-no, 1-on errs, 2-allways */
  76         unsigned char *sb_cp_table;     /* code page tables: */
  77                                         /*      128 bytes uppercasing table & */
  78                                         /*      128 bytes lowercasing table */
  79         __le32 *sb_bmp_dir;             /* main bitmap directory */
  80         unsigned sb_c_bitmap;           /* current bitmap */
  81         unsigned sb_max_fwd_alloc;      /* max forwad allocation */
  82         int sb_timeshift;
  83         struct rcu_head rcu;
  84 };
  85
  86 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
  87
  88 struct quad_buffer_head {
  89         struct buffer_head *bh[4];
  90         void *data;
  91 };
  92
  93 /* The b-tree down pointer from a dir entry */
  94
  95 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
  96 {
  97   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
  98   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
  99 }
 100
 101 /* The first dir entry in a dnode */
 102
 103 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
 104 {
 105   return (void *) dnode->dirent;
 106 }
 107
 108 /* The end+1 of the dir entries */
 109
 110 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
 111 {
 112   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)));
 113   return (void *) dnode + le32_to_cpu(dnode->first_free);
 114 }
 115
 116 /* The dir entry after dir entry de */
 117
 118 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
 119 {
 120   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)));
 121   return (void *) de + le16_to_cpu(de->length);
 122 }
 123
 124 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
 125 {
 126         return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
 127 }
 128
 129 static inline struct extended_attribute *fnode_end_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) + le16_to_cpu(fnode->ea_size_s));
 132 }
 133
 134 static unsigned ea_valuelen(struct extended_attribute *ea)
 135 {
 136         return ea->valuelen_lo + 256 * ea->valuelen_hi;
 137 }
 138
 139 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
 140 {
 141         return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
 142 }
 143
 144 static inline secno ea_sec(struct extended_attribute *ea)
 145 {
 146         return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
 147 }
 148
 149 static inline secno ea_len(struct extended_attribute *ea)
 150 {
 151         return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
 152 }
 153
 154 static inline char *ea_data(struct extended_attribute *ea)
 155 {
 156         return (char *)((char *)ea + 5 + ea->namelen);
 157 }
 158
 159 static inline unsigned de_size(int namelen, secno down_ptr)
 160 {
 161         return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
 162 }
 163
 164 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
 165 {
 166         int a;
 167         int n;
 168         if (!dst || !src) return;
 169         a = dst->down;
 170         n = dst->not_8x3;
 171         memcpy((char *)dst + 2, (char *)src + 2, 28);
 172         dst->down = a;
 173         dst->not_8x3 = n;
 174 }
 175
 176 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
 177 {
 178         int i;
 179         if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
 180         if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
 181         for (i = 1; i < n; i++)
 182                 if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
 183                         return i + 1;
 184         return 0;
 185 }
 186
 187 /* alloc.c */
 188
 189 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
 190 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
 191 int hpfs_alloc_if_possible(struct super_block *, secno);
 192 void hpfs_free_sectors(struct super_block *, secno, unsigned);
 193 int hpfs_check_free_dnodes(struct super_block *, int);
 194 void hpfs_free_dnode(struct super_block *, secno);
 195 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
 196 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
 197 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
 198
 199 /* anode.c */
 200
 201 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
 202 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
 203 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
 204 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
 205 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
 206 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
 207 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
 208 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
 209
 210 /* buffer.c */
 211
 212 void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
 213 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
 214 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
 215 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
 216 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
 217 void hpfs_brelse4(struct quad_buffer_head *);
 218 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
 219
 220 /* dentry.c */
 221
 222 extern const struct dentry_operations hpfs_dentry_operations;
 223
 224 /* dir.c */
 225
 226 struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
 227 extern const struct file_operations hpfs_dir_ops;
 228
 229 /* dnode.c */
 230
 231 void hpfs_add_pos(struct inode *, loff_t *);
 232 void hpfs_del_pos(struct inode *, loff_t *);
 233 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
 234                                 const unsigned char *, unsigned, secno);
 235 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
 236                     struct hpfs_dirent *);
 237 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
 238 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
 239 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
 240 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
 241 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
 242                                const unsigned char *, unsigned, dnode_secno *,
 243                                struct quad_buffer_head *);
 244 void hpfs_remove_dtree(struct super_block *, dnode_secno);
 245 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
 246
 247 /* ea.c */
 248
 249 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
 250 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
 251 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
 252 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
 253                  const char *, int);
 254
 255 /* file.c */
 256
 257 int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
 258 void hpfs_truncate(struct inode *);
 259 extern const struct file_operations hpfs_file_ops;
 260 extern const struct inode_operations hpfs_file_iops;
 261 extern const struct address_space_operations hpfs_aops;
 262
 263 /* inode.c */
 264
 265 void hpfs_init_inode(struct inode *);
 266 void hpfs_read_inode(struct inode *);
 267 void hpfs_write_inode(struct inode *);
 268 void hpfs_write_inode_nolock(struct inode *);
 269 int hpfs_setattr(struct dentry *, struct iattr *);
 270 void hpfs_write_if_changed(struct inode *);
 271 void hpfs_evict_inode(struct inode *);
 272
 273 /* map.c */
 274
 275 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
 276 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
 277 void hpfs_prefetch_bitmap(struct super_block *, unsigned);
 278 unsigned char *hpfs_load_code_page(struct super_block *, secno);
 279 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
 280 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
 281 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
 282 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
 283 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
 284
 285 /* name.c */
 286
 287 unsigned char hpfs_upcase(unsigned char *, unsigned char);
 288 int hpfs_chk_name(const unsigned char *, unsigned *);
 289 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
 290 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
 291                        const unsigned char *, unsigned, int);
 292 int hpfs_is_name_long(const unsigned char *, unsigned);
 293 void hpfs_adjust_length(const unsigned char *, unsigned *);
 294
 295 /* namei.c */
 296
 297 extern const struct inode_operations hpfs_dir_iops;
 298 extern const struct address_space_operations hpfs_symlink_aops;
 299
 300 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
 301 {
 302         return list_entry(inode, struct hpfs_inode_info, vfs_inode);
 303 }
 304
 305 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
 306 {
 307         return sb->s_fs_info;
 308 }
 309
 310 /* super.c */
 311
 312 __printf(2, 3)
 313 void hpfs_error(struct super_block *, const char *, ...);
 314 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
 315 unsigned hpfs_get_free_dnodes(struct super_block *);
 316
 317 /*
 318  * local time (HPFS) to GMT (Unix)
 319  */
 320
 321 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
 322 {
 323         extern struct timezone sys_tz;
 324         return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
 325 }
 326
 327 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
 328 {
 329         extern struct timezone sys_tz;
 330         return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
 331 }
 332
 333 /*
 334  * Locking:
 335  *
 336  * hpfs_lock() locks the whole filesystem. It must be taken
 337  * on any method called by the VFS.
 338  *
 339  * We don't do any per-file locking anymore, it is hard to
 340  * review and HPFS is not performance-sensitive anyway.
 341  */
 342 static inline void hpfs_lock(struct super_block *s)
 343 {
 344         struct hpfs_sb_info *sbi = hpfs_sb(s);
 345         mutex_lock(&sbi->hpfs_mutex);
 346 }
 347
 348 static inline void hpfs_unlock(struct super_block *s)
 349 {
 350         struct hpfs_sb_info *sbi = hpfs_sb(s);
 351         mutex_unlock(&sbi->hpfs_mutex);
 352 }
 353
 354 static inline void hpfs_lock_assert(struct super_block *s)
 355 {
 356         struct hpfs_sb_info *sbi = hpfs_sb(s);
 357         WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
 358 }