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 #ifdef pr_fmt
  12 #undef pr_fmt
  13 #endif
  14
  15 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  16
  17 #include <linux/mutex.h>
  18 #include <linux/pagemap.h>
  19 #include <linux/buffer_head.h>
  20 #include <linux/slab.h>
  21 #include <linux/sched.h>
  22 #include <linux/blkdev.h>
  23 #include <asm/unaligned.h>
  24
  25 #include "hpfs.h"
  26
  27 #define EIOERROR  EIO
  28 #define EFSERROR  EPERM
  29 #define EMEMERROR ENOMEM
  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
  93 /* Four 512-byte buffers and the 2k block obtained by concatenating them */
  94
  95 struct quad_buffer_head {
  96         struct buffer_head *bh[4];
  97         void *data;
  98 };
  99
 100 /* The b-tree down pointer from a dir entry */
 101
 102 static inline dnode_secno de_down_pointer (struct hpfs_dirent *de)
 103 {
 104   CHKCOND(de->down,("HPFS: de_down_pointer: !de->down\n"));
 105   return le32_to_cpu(*(__le32 *) ((void *) de + le16_to_cpu(de->length) - 4));
 106 }
 107
 108 /* The first dir entry in a dnode */
 109
 110 static inline struct hpfs_dirent *dnode_first_de (struct dnode *dnode)
 111 {
 112   return (void *) dnode->dirent;
 113 }
 114
 115 /* The end+1 of the dir entries */
 116
 117 static inline struct hpfs_dirent *dnode_end_de (struct dnode *dnode)
 118 {
 119   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)));
 120   return (void *) dnode + le32_to_cpu(dnode->first_free);
 121 }
 122
 123 /* The dir entry after dir entry de */
 124
 125 static inline struct hpfs_dirent *de_next_de (struct hpfs_dirent *de)
 126 {
 127   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)));
 128   return (void *) de + le16_to_cpu(de->length);
 129 }
 130
 131 static inline struct extended_attribute *fnode_ea(struct fnode *fnode)
 132 {
 133         return (struct extended_attribute *)((char *)fnode + le16_to_cpu(fnode->ea_offs) + le16_to_cpu(fnode->acl_size_s));
 134 }
 135
 136 static inline struct extended_attribute *fnode_end_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) + le16_to_cpu(fnode->ea_size_s));
 139 }
 140
 141 static unsigned ea_valuelen(struct extended_attribute *ea)
 142 {
 143         return ea->valuelen_lo + 256 * ea->valuelen_hi;
 144 }
 145
 146 static inline struct extended_attribute *next_ea(struct extended_attribute *ea)
 147 {
 148         return (struct extended_attribute *)((char *)ea + 5 + ea->namelen + ea_valuelen(ea));
 149 }
 150
 151 static inline secno ea_sec(struct extended_attribute *ea)
 152 {
 153         return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
 154 }
 155
 156 static inline secno ea_len(struct extended_attribute *ea)
 157 {
 158         return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
 159 }
 160
 161 static inline char *ea_data(struct extended_attribute *ea)
 162 {
 163         return (char *)((char *)ea + 5 + ea->namelen);
 164 }
 165
 166 static inline unsigned de_size(int namelen, secno down_ptr)
 167 {
 168         return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
 169 }
 170
 171 static inline void copy_de(struct hpfs_dirent *dst, struct hpfs_dirent *src)
 172 {
 173         int a;
 174         int n;
 175         if (!dst || !src) return;
 176         a = dst->down;
 177         n = dst->not_8x3;
 178         memcpy((char *)dst + 2, (char *)src + 2, 28);
 179         dst->down = a;
 180         dst->not_8x3 = n;
 181 }
 182
 183 static inline unsigned tstbits(__le32 *bmp, unsigned b, unsigned n)
 184 {
 185         int i;
 186         if ((b >= 0x4000) || (b + n - 1 >= 0x4000)) return n;
 187         if (!((le32_to_cpu(bmp[(b & 0x3fff) >> 5]) >> (b & 0x1f)) & 1)) return 1;
 188         for (i = 1; i < n; i++)
 189                 if (!((le32_to_cpu(bmp[((b+i) & 0x3fff) >> 5]) >> ((b+i) & 0x1f)) & 1))
 190                         return i + 1;
 191         return 0;
 192 }
 193
 194 /* alloc.c */
 195
 196 int hpfs_chk_sectors(struct super_block *, secno, int, char *);
 197 secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
 198 int hpfs_alloc_if_possible(struct super_block *, secno);
 199 void hpfs_free_sectors(struct super_block *, secno, unsigned);
 200 int hpfs_check_free_dnodes(struct super_block *, int);
 201 void hpfs_free_dnode(struct super_block *, secno);
 202 struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
 203 struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
 204 struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
 205 int hpfs_trim_fs(struct super_block *, u64, u64, u64, unsigned *);
 206
 207 /* anode.c */
 208
 209 secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
 210 secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
 211 void hpfs_remove_btree(struct super_block *, struct bplus_header *);
 212 int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
 213 int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
 214 void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
 215 void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
 216 void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
 217
 218 /* buffer.c */
 219
 220 void hpfs_prefetch_sectors(struct super_block *, unsigned, int);
 221 void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
 222 void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
 223 void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
 224 void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
 225 void hpfs_brelse4(struct quad_buffer_head *);
 226 void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
 227
 228 /* dentry.c */
 229
 230 extern const struct dentry_operations hpfs_dentry_operations;
 231
 232 /* dir.c */
 233
 234 struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
 235 extern const struct file_operations hpfs_dir_ops;
 236
 237 /* dnode.c */
 238
 239 void hpfs_add_pos(struct inode *, loff_t *);
 240 void hpfs_del_pos(struct inode *, loff_t *);
 241 struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
 242                                 const unsigned char *, unsigned, secno);
 243 int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
 244                     struct hpfs_dirent *);
 245 int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
 246 void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
 247 dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
 248 struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
 249 struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
 250                                const unsigned char *, unsigned, dnode_secno *,
 251                                struct quad_buffer_head *);
 252 void hpfs_remove_dtree(struct super_block *, dnode_secno);
 253 struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
 254
 255 /* ea.c */
 256
 257 void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
 258 int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
 259 char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
 260 void hpfs_set_ea(struct inode *, struct fnode *, const char *,
 261                  const char *, int);
 262
 263 /* file.c */
 264
 265 int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
 266 void hpfs_truncate(struct inode *);
 267 extern const struct file_operations hpfs_file_ops;
 268 extern const struct inode_operations hpfs_file_iops;
 269 extern const struct address_space_operations hpfs_aops;
 270
 271 /* inode.c */
 272
 273 void hpfs_init_inode(struct inode *);
 274 void hpfs_read_inode(struct inode *);
 275 void hpfs_write_inode(struct inode *);
 276 void hpfs_write_inode_nolock(struct inode *);
 277 int hpfs_setattr(struct dentry *, struct iattr *);
 278 void hpfs_write_if_changed(struct inode *);
 279 void hpfs_evict_inode(struct inode *);
 280
 281 /* map.c */
 282
 283 __le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
 284 __le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
 285 void hpfs_prefetch_bitmap(struct super_block *, unsigned);
 286 unsigned char *hpfs_load_code_page(struct super_block *, secno);
 287 __le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
 288 struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
 289 struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
 290 struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
 291 dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
 292
 293 /* name.c */
 294
 295 unsigned char hpfs_upcase(unsigned char *, unsigned char);
 296 int hpfs_chk_name(const unsigned char *, unsigned *);
 297 unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
 298 int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
 299                        const unsigned char *, unsigned, int);
 300 int hpfs_is_name_long(const unsigned char *, unsigned);
 301 void hpfs_adjust_length(const unsigned char *, unsigned *);
 302
 303 /* namei.c */
 304
 305 extern const struct inode_operations hpfs_dir_iops;
 306 extern const struct address_space_operations hpfs_symlink_aops;
 307
 308 static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
 309 {
 310         return container_of(inode, struct hpfs_inode_info, vfs_inode);
 311 }
 312
 313 static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
 314 {
 315         return sb->s_fs_info;
 316 }
 317
 318 /* super.c */
 319
 320 __printf(2, 3)
 321 void hpfs_error(struct super_block *, const char *, ...);
 322 int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
 323 unsigned hpfs_get_free_dnodes(struct super_block *);
 324 long hpfs_ioctl(struct file *file, unsigned cmd, unsigned long arg);
 325
 326 /*
 327  * local time (HPFS) to GMT (Unix)
 328  */
 329
 330 static inline time_t local_to_gmt(struct super_block *s, time32_t t)
 331 {
 332         extern struct timezone sys_tz;
 333         return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
 334 }
 335
 336 static inline time32_t gmt_to_local(struct super_block *s, time_t t)
 337 {
 338         extern struct timezone sys_tz;
 339         return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
 340 }
 341
 342 /*
 343  * Locking:
 344  *
 345  * hpfs_lock() locks the whole filesystem. It must be taken
 346  * on any method called by the VFS.
 347  *
 348  * We don't do any per-file locking anymore, it is hard to
 349  * review and HPFS is not performance-sensitive anyway.
 350  */
 351 static inline void hpfs_lock(struct super_block *s)
 352 {
 353         struct hpfs_sb_info *sbi = hpfs_sb(s);
 354         mutex_lock(&sbi->hpfs_mutex);
 355 }
 356
 357 static inline void hpfs_unlock(struct super_block *s)
 358 {
 359         struct hpfs_sb_info *sbi = hpfs_sb(s);
 360         mutex_unlock(&sbi->hpfs_mutex);
 361 }
 362
 363 static inline void hpfs_lock_assert(struct super_block *s)
 364 {
 365         struct hpfs_sb_info *sbi = hpfs_sb(s);
 366         WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
 367 }