LXR linux/fs/hpfs/hpfs

   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
  45struct 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
  63struct 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
  93struct 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
 100static 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
 108static 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
 115static 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
 123static 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
 129static 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
 134static 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
 139static unsigned ea_valuelen(struct extended_attribute *ea)
 140{
 141        return ea->valuelen_lo + 256 * ea->valuelen_hi;
 142}
 143
 144static 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
 149static inline secno ea_sec(struct extended_attribute *ea)
 150{
 151        return le32_to_cpu(get_unaligned((secno *)((char *)ea + 9 + ea->namelen)));
 152}
 153
 154static inline secno ea_len(struct extended_attribute *ea)
 155{
 156        return le32_to_cpu(get_unaligned((secno *)((char *)ea + 5 + ea->namelen)));
 157}
 158
 159static inline char *ea_data(struct extended_attribute *ea)
 160{
 161        return (char *)((char *)ea + 5 + ea->namelen);
 162}
 163
 164static inline unsigned de_size(int namelen, secno down_ptr)
 165{
 166        return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
 167}
 168
 169static 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
 181static 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
 194int hpfs_chk_sectors(struct super_block *, secno, int, char *);
 195secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
 196int hpfs_alloc_if_possible(struct super_block *, secno);
 197void hpfs_free_sectors(struct super_block *, secno, unsigned);
 198int hpfs_check_free_dnodes(struct super_block *, int);
 199void hpfs_free_dnode(struct super_block *, secno);
 200struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
 201struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
 202struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
 203
 204/* anode.c */
 205
 206secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
 207secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
 208void hpfs_remove_btree(struct super_block *, struct bplus_header *);
 209int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
 210int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
 211void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
 212void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
 213void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
 214
 215/* buffer.c */
 216
 217void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
 218void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
 219void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
 220void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
 221void hpfs_brelse4(struct quad_buffer_head *);
 222void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
 223
 224/* dentry.c */
 225
 226extern const struct dentry_operations hpfs_dentry_operations;
 227
 228/* dir.c */
 229
 230struct dentry *hpfs_lookup(struct inode *, struct dentry *, struct nameidata *);
 231extern const struct file_operations hpfs_dir_ops;
 232
 233/* dnode.c */
 234
 235void hpfs_add_pos(struct inode *, loff_t *);
 236void hpfs_del_pos(struct inode *, loff_t *);
 237struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
 238                                const unsigned char *, unsigned, secno);
 239int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
 240                    struct hpfs_dirent *);
 241int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
 242void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
 243dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
 244struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
 245struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
 246                               const unsigned char *, unsigned, dnode_secno *,
 247                               struct quad_buffer_head *);
 248void hpfs_remove_dtree(struct super_block *, dnode_secno);
 249struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
 250
 251/* ea.c */
 252
 253void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
 254int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
 255char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
 256void hpfs_set_ea(struct inode *, struct fnode *, const char *,
 257                 const char *, int);
 258
 259/* file.c */
 260
 261int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
 262extern const struct file_operations hpfs_file_ops;
 263extern const struct inode_operations hpfs_file_iops;
 264extern const struct address_space_operations hpfs_aops;
 265
 266/* inode.c */
 267
 268void hpfs_init_inode(struct inode *);
 269void hpfs_read_inode(struct inode *);
 270void hpfs_write_inode(struct inode *);
 271void hpfs_write_inode_nolock(struct inode *);
 272int hpfs_setattr(struct dentry *, struct iattr *);
 273void hpfs_write_if_changed(struct inode *);
 274void hpfs_evict_inode(struct inode *);
 275
 276/* map.c */
 277
 278unsigned *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
 279unsigned *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
 280unsigned char *hpfs_load_code_page(struct super_block *, secno);
 281secno *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
 282struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
 283struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
 284struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
 285dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
 286
 287/* name.c */
 288
 289unsigned char hpfs_upcase(unsigned char *, unsigned char);
 290int hpfs_chk_name(const unsigned char *, unsigned *);
 291unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
 292int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
 293                       const unsigned char *, unsigned, int);
 294int hpfs_is_name_long(const unsigned char *, unsigned);
 295void hpfs_adjust_length(const unsigned char *, unsigned *);
 296
 297/* namei.c */
 298
 299extern const struct inode_operations hpfs_dir_iops;
 300extern const struct address_space_operations hpfs_symlink_aops;
 301
 302static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
 303{
 304        return list_entry(inode, struct hpfs_inode_info, vfs_inode);
 305}
 306
 307static 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__printf(2, 3)
 315void hpfs_error(struct super_block *, const char *, ...);
 316int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
 317unsigned hpfs_count_one_bitmap(struct super_block *, secno);
 318
 319/*
 320 * local time (HPFS) to GMT (Unix)
 321 */
 322
 323static 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
 329static 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 */
 344static 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
 350static 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
 356static 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}
 361