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
  38struct 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
  56struct 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        uid_t sb_uid;                   /* uid from mount options */
  67        gid_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
  86struct 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
  93static 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
 101static 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
 108static 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
 116static 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
 122static 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
 127static 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
 132static unsigned ea_valuelen(struct extended_attribute *ea)
 133{
 134        return ea->valuelen_lo + 256 * ea->valuelen_hi;
 135}
 136
 137static 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
 142static inline secno ea_sec(struct extended_attribute *ea)
 143{
 144        return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 9 + ea->namelen)));
 145}
 146
 147static inline secno ea_len(struct extended_attribute *ea)
 148{
 149        return le32_to_cpu(get_unaligned((__le32 *)((char *)ea + 5 + ea->namelen)));
 150}
 151
 152static inline char *ea_data(struct extended_attribute *ea)
 153{
 154        return (char *)((char *)ea + 5 + ea->namelen);
 155}
 156
 157static inline unsigned de_size(int namelen, secno down_ptr)
 158{
 159        return ((0x1f + namelen + 3) & ~3) + (down_ptr ? 4 : 0);
 160}
 161
 162static 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
 174static 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
 187int hpfs_chk_sectors(struct super_block *, secno, int, char *);
 188secno hpfs_alloc_sector(struct super_block *, secno, unsigned, int);
 189int hpfs_alloc_if_possible(struct super_block *, secno);
 190void hpfs_free_sectors(struct super_block *, secno, unsigned);
 191int hpfs_check_free_dnodes(struct super_block *, int);
 192void hpfs_free_dnode(struct super_block *, secno);
 193struct dnode *hpfs_alloc_dnode(struct super_block *, secno, dnode_secno *, struct quad_buffer_head *);
 194struct fnode *hpfs_alloc_fnode(struct super_block *, secno, fnode_secno *, struct buffer_head **);
 195struct anode *hpfs_alloc_anode(struct super_block *, secno, anode_secno *, struct buffer_head **);
 196
 197/* anode.c */
 198
 199secno hpfs_bplus_lookup(struct super_block *, struct inode *, struct bplus_header *, unsigned, struct buffer_head *);
 200secno hpfs_add_sector_to_btree(struct super_block *, secno, int, unsigned);
 201void hpfs_remove_btree(struct super_block *, struct bplus_header *);
 202int hpfs_ea_read(struct super_block *, secno, int, unsigned, unsigned, char *);
 203int hpfs_ea_write(struct super_block *, secno, int, unsigned, unsigned, const char *);
 204void hpfs_ea_remove(struct super_block *, secno, int, unsigned);
 205void hpfs_truncate_btree(struct super_block *, secno, int, unsigned);
 206void hpfs_remove_fnode(struct super_block *, fnode_secno fno);
 207
 208/* buffer.c */
 209
 210void *hpfs_map_sector(struct super_block *, unsigned, struct buffer_head **, int);
 211void *hpfs_get_sector(struct super_block *, unsigned, struct buffer_head **);
 212void *hpfs_map_4sectors(struct super_block *, unsigned, struct quad_buffer_head *, int);
 213void *hpfs_get_4sectors(struct super_block *, unsigned, struct quad_buffer_head *);
 214void hpfs_brelse4(struct quad_buffer_head *);
 215void hpfs_mark_4buffers_dirty(struct quad_buffer_head *);
 216
 217/* dentry.c */
 218
 219extern const struct dentry_operations hpfs_dentry_operations;
 220
 221/* dir.c */
 222
 223struct dentry *hpfs_lookup(struct inode *, struct dentry *, unsigned int);
 224extern const struct file_operations hpfs_dir_ops;
 225
 226/* dnode.c */
 227
 228void hpfs_add_pos(struct inode *, loff_t *);
 229void hpfs_del_pos(struct inode *, loff_t *);
 230struct hpfs_dirent *hpfs_add_de(struct super_block *, struct dnode *,
 231                                const unsigned char *, unsigned, secno);
 232int hpfs_add_dirent(struct inode *, const unsigned char *, unsigned,
 233                    struct hpfs_dirent *);
 234int hpfs_remove_dirent(struct inode *, dnode_secno, struct hpfs_dirent *, struct quad_buffer_head *, int);
 235void hpfs_count_dnodes(struct super_block *, dnode_secno, int *, int *, int *);
 236dnode_secno hpfs_de_as_down_as_possible(struct super_block *, dnode_secno dno);
 237struct hpfs_dirent *map_pos_dirent(struct inode *, loff_t *, struct quad_buffer_head *);
 238struct hpfs_dirent *map_dirent(struct inode *, dnode_secno,
 239                               const unsigned char *, unsigned, dnode_secno *,
 240                               struct quad_buffer_head *);
 241void hpfs_remove_dtree(struct super_block *, dnode_secno);
 242struct hpfs_dirent *map_fnode_dirent(struct super_block *, fnode_secno, struct fnode *, struct quad_buffer_head *);
 243
 244/* ea.c */
 245
 246void hpfs_ea_ext_remove(struct super_block *, secno, int, unsigned);
 247int hpfs_read_ea(struct super_block *, struct fnode *, char *, char *, int);
 248char *hpfs_get_ea(struct super_block *, struct fnode *, char *, int *);
 249void hpfs_set_ea(struct inode *, struct fnode *, const char *,
 250                 const char *, int);
 251
 252/* file.c */
 253
 254int hpfs_file_fsync(struct file *, loff_t, loff_t, int);
 255extern const struct file_operations hpfs_file_ops;
 256extern const struct inode_operations hpfs_file_iops;
 257extern const struct address_space_operations hpfs_aops;
 258
 259/* inode.c */
 260
 261void hpfs_init_inode(struct inode *);
 262void hpfs_read_inode(struct inode *);
 263void hpfs_write_inode(struct inode *);
 264void hpfs_write_inode_nolock(struct inode *);
 265int hpfs_setattr(struct dentry *, struct iattr *);
 266void hpfs_write_if_changed(struct inode *);
 267void hpfs_evict_inode(struct inode *);
 268
 269/* map.c */
 270
 271__le32 *hpfs_map_dnode_bitmap(struct super_block *, struct quad_buffer_head *);
 272__le32 *hpfs_map_bitmap(struct super_block *, unsigned, struct quad_buffer_head *, char *);
 273unsigned char *hpfs_load_code_page(struct super_block *, secno);
 274__le32 *hpfs_load_bitmap_directory(struct super_block *, secno bmp);
 275struct fnode *hpfs_map_fnode(struct super_block *s, ino_t, struct buffer_head **);
 276struct anode *hpfs_map_anode(struct super_block *s, anode_secno, struct buffer_head **);
 277struct dnode *hpfs_map_dnode(struct super_block *s, dnode_secno, struct quad_buffer_head *);
 278dnode_secno hpfs_fnode_dno(struct super_block *s, ino_t ino);
 279
 280/* name.c */
 281
 282unsigned char hpfs_upcase(unsigned char *, unsigned char);
 283int hpfs_chk_name(const unsigned char *, unsigned *);
 284unsigned char *hpfs_translate_name(struct super_block *, unsigned char *, unsigned, int, int);
 285int hpfs_compare_names(struct super_block *, const unsigned char *, unsigned,
 286                       const unsigned char *, unsigned, int);
 287int hpfs_is_name_long(const unsigned char *, unsigned);
 288void hpfs_adjust_length(const unsigned char *, unsigned *);
 289
 290/* namei.c */
 291
 292extern const struct inode_operations hpfs_dir_iops;
 293extern const struct address_space_operations hpfs_symlink_aops;
 294
 295static inline struct hpfs_inode_info *hpfs_i(struct inode *inode)
 296{
 297        return list_entry(inode, struct hpfs_inode_info, vfs_inode);
 298}
 299
 300static inline struct hpfs_sb_info *hpfs_sb(struct super_block *sb)
 301{
 302        return sb->s_fs_info;
 303}
 304
 305/* super.c */
 306
 307__printf(2, 3)
 308void hpfs_error(struct super_block *, const char *, ...);
 309int hpfs_stop_cycles(struct super_block *, int, int *, int *, char *);
 310unsigned hpfs_count_one_bitmap(struct super_block *, secno);
 311
 312/*
 313 * local time (HPFS) to GMT (Unix)
 314 */
 315
 316static inline time_t local_to_gmt(struct super_block *s, time32_t t)
 317{
 318        extern struct timezone sys_tz;
 319        return t + sys_tz.tz_minuteswest * 60 + hpfs_sb(s)->sb_timeshift;
 320}
 321
 322static inline time32_t gmt_to_local(struct super_block *s, time_t t)
 323{
 324        extern struct timezone sys_tz;
 325        return t - sys_tz.tz_minuteswest * 60 - hpfs_sb(s)->sb_timeshift;
 326}
 327
 328/*
 329 * Locking:
 330 *
 331 * hpfs_lock() locks the whole filesystem. It must be taken
 332 * on any method called by the VFS.
 333 *
 334 * We don't do any per-file locking anymore, it is hard to
 335 * review and HPFS is not performance-sensitive anyway.
 336 */
 337static inline void hpfs_lock(struct super_block *s)
 338{
 339        struct hpfs_sb_info *sbi = hpfs_sb(s);
 340        mutex_lock(&sbi->hpfs_mutex);
 341}
 342
 343static inline void hpfs_unlock(struct super_block *s)
 344{
 345        struct hpfs_sb_info *sbi = hpfs_sb(s);
 346        mutex_unlock(&sbi->hpfs_mutex);
 347}
 348
 349static inline void hpfs_lock_assert(struct super_block *s)
 350{
 351        struct hpfs_sb_info *sbi = hpfs_sb(s);
 352        WARN_ON(!mutex_is_locked(&sbi->hpfs_mutex));
 353}
 354