1da177e4c3
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
493 lines
17 KiB
C
493 lines
17 KiB
C
/*
|
|
* linux/fs/hpfs/hpfs.h
|
|
*
|
|
* HPFS structures by Chris Smith, 1993
|
|
*
|
|
* a little bit modified by Mikulas Patocka, 1998-1999
|
|
*/
|
|
|
|
/* The paper
|
|
|
|
Duncan, Roy
|
|
Design goals and implementation of the new High Performance File System
|
|
Microsoft Systems Journal Sept 1989 v4 n5 p1(13)
|
|
|
|
describes what HPFS looked like when it was new, and it is the source
|
|
of most of the information given here. The rest is conjecture.
|
|
|
|
For definitive information on the Duncan paper, see it, not this file.
|
|
For definitive information on HPFS, ask somebody else -- this is guesswork.
|
|
There are certain to be many mistakes. */
|
|
|
|
/* Notation */
|
|
|
|
typedef unsigned secno; /* sector number, partition relative */
|
|
|
|
typedef secno dnode_secno; /* sector number of a dnode */
|
|
typedef secno fnode_secno; /* sector number of an fnode */
|
|
typedef secno anode_secno; /* sector number of an anode */
|
|
|
|
typedef u32 time32_t; /* 32-bit time_t type */
|
|
|
|
/* sector 0 */
|
|
|
|
/* The boot block is very like a FAT boot block, except that the
|
|
29h signature byte is 28h instead, and the ID string is "HPFS". */
|
|
|
|
#define BB_MAGIC 0xaa55
|
|
|
|
struct hpfs_boot_block
|
|
{
|
|
unsigned char jmp[3];
|
|
unsigned char oem_id[8];
|
|
unsigned char bytes_per_sector[2]; /* 512 */
|
|
unsigned char sectors_per_cluster;
|
|
unsigned char n_reserved_sectors[2];
|
|
unsigned char n_fats;
|
|
unsigned char n_rootdir_entries[2];
|
|
unsigned char n_sectors_s[2];
|
|
unsigned char media_byte;
|
|
unsigned short sectors_per_fat;
|
|
unsigned short sectors_per_track;
|
|
unsigned short heads_per_cyl;
|
|
unsigned int n_hidden_sectors;
|
|
unsigned int n_sectors_l; /* size of partition */
|
|
unsigned char drive_number;
|
|
unsigned char mbz;
|
|
unsigned char sig_28h; /* 28h */
|
|
unsigned char vol_serno[4];
|
|
unsigned char vol_label[11];
|
|
unsigned char sig_hpfs[8]; /* "HPFS " */
|
|
unsigned char pad[448];
|
|
unsigned short magic; /* aa55 */
|
|
};
|
|
|
|
|
|
/* sector 16 */
|
|
|
|
/* The super block has the pointer to the root directory. */
|
|
|
|
#define SB_MAGIC 0xf995e849
|
|
|
|
struct hpfs_super_block
|
|
{
|
|
unsigned magic; /* f995 e849 */
|
|
unsigned magic1; /* fa53 e9c5, more magic? */
|
|
/*unsigned huh202;*/ /* ?? 202 = N. of B. in 1.00390625 S.*/
|
|
char version; /* version of a filesystem usually 2 */
|
|
char funcversion; /* functional version - oldest version
|
|
of filesystem that can understand
|
|
this disk */
|
|
unsigned short int zero; /* 0 */
|
|
fnode_secno root; /* fnode of root directory */
|
|
secno n_sectors; /* size of filesystem */
|
|
unsigned n_badblocks; /* number of bad blocks */
|
|
secno bitmaps; /* pointers to free space bit maps */
|
|
unsigned zero1; /* 0 */
|
|
secno badblocks; /* bad block list */
|
|
unsigned zero3; /* 0 */
|
|
time32_t last_chkdsk; /* date last checked, 0 if never */
|
|
/*unsigned zero4;*/ /* 0 */
|
|
time32_t last_optimize; /* date last optimized, 0 if never */
|
|
secno n_dir_band; /* number of sectors in dir band */
|
|
secno dir_band_start; /* first sector in dir band */
|
|
secno dir_band_end; /* last sector in dir band */
|
|
secno dir_band_bitmap; /* free space map, 1 dnode per bit */
|
|
char volume_name[32]; /* not used */
|
|
secno user_id_table; /* 8 preallocated sectors - user id */
|
|
unsigned zero6[103]; /* 0 */
|
|
};
|
|
|
|
|
|
/* sector 17 */
|
|
|
|
/* The spare block has pointers to spare sectors. */
|
|
|
|
#define SP_MAGIC 0xf9911849
|
|
|
|
struct hpfs_spare_block
|
|
{
|
|
unsigned magic; /* f991 1849 */
|
|
unsigned magic1; /* fa52 29c5, more magic? */
|
|
|
|
unsigned dirty: 1; /* 0 clean, 1 "improperly stopped" */
|
|
/*unsigned flag1234: 4;*/ /* unknown flags */
|
|
unsigned sparedir_used: 1; /* spare dirblks used */
|
|
unsigned hotfixes_used: 1; /* hotfixes used */
|
|
unsigned bad_sector: 1; /* bad sector, corrupted disk (???) */
|
|
unsigned bad_bitmap: 1; /* bad bitmap */
|
|
unsigned fast: 1; /* partition was fast formatted */
|
|
unsigned old_wrote: 1; /* old version wrote to partion */
|
|
unsigned old_wrote_1: 1; /* old version wrote to partion (?) */
|
|
unsigned install_dasd_limits: 1; /* HPFS386 flags */
|
|
unsigned resynch_dasd_limits: 1;
|
|
unsigned dasd_limits_operational: 1;
|
|
unsigned multimedia_active: 1;
|
|
unsigned dce_acls_active: 1;
|
|
unsigned dasd_limits_dirty: 1;
|
|
unsigned flag67: 2;
|
|
unsigned char mm_contlgulty;
|
|
unsigned char unused;
|
|
|
|
secno hotfix_map; /* info about remapped bad sectors */
|
|
unsigned n_spares_used; /* number of hotfixes */
|
|
unsigned n_spares; /* number of spares in hotfix map */
|
|
unsigned n_dnode_spares_free; /* spare dnodes unused */
|
|
unsigned n_dnode_spares; /* length of spare_dnodes[] list,
|
|
follows in this block*/
|
|
secno code_page_dir; /* code page directory block */
|
|
unsigned n_code_pages; /* number of code pages */
|
|
/*unsigned large_numbers[2];*/ /* ?? */
|
|
unsigned super_crc; /* on HPFS386 and LAN Server this is
|
|
checksum of superblock, on normal
|
|
OS/2 unused */
|
|
unsigned spare_crc; /* on HPFS386 checksum of spareblock */
|
|
unsigned zero1[15]; /* unused */
|
|
dnode_secno spare_dnodes[100]; /* emergency free dnode list */
|
|
unsigned zero2[1]; /* room for more? */
|
|
};
|
|
|
|
/* The bad block list is 4 sectors long. The first word must be zero,
|
|
the remaining words give n_badblocks bad block numbers.
|
|
I bet you can see it coming... */
|
|
|
|
#define BAD_MAGIC 0
|
|
|
|
/* The hotfix map is 4 sectors long. It looks like
|
|
|
|
secno from[n_spares];
|
|
secno to[n_spares];
|
|
|
|
The to[] list is initialized to point to n_spares preallocated empty
|
|
sectors. The from[] list contains the sector numbers of bad blocks
|
|
which have been remapped to corresponding sectors in the to[] list.
|
|
n_spares_used gives the length of the from[] list. */
|
|
|
|
|
|
/* Sectors 18 and 19 are preallocated and unused.
|
|
Maybe they're spares for 16 and 17, but simple substitution fails. */
|
|
|
|
|
|
/* The code page info pointed to by the spare block consists of an index
|
|
block and blocks containing uppercasing tables. I don't know what
|
|
these are for (CHKDSK, maybe?) -- OS/2 does not seem to use them
|
|
itself. Linux doesn't use them either. */
|
|
|
|
/* block pointed to by spareblock->code_page_dir */
|
|
|
|
#define CP_DIR_MAGIC 0x494521f7
|
|
|
|
struct code_page_directory
|
|
{
|
|
unsigned magic; /* 4945 21f7 */
|
|
unsigned n_code_pages; /* number of pointers following */
|
|
unsigned zero1[2];
|
|
struct {
|
|
unsigned short ix; /* index */
|
|
unsigned short code_page_number; /* code page number */
|
|
unsigned bounds; /* matches corresponding word
|
|
in data block */
|
|
secno code_page_data; /* sector number of a code_page_data
|
|
containing c.p. array */
|
|
unsigned short index; /* index in c.p. array in that sector*/
|
|
unsigned short unknown; /* some unknown value; usually 0;
|
|
2 in Japanese version */
|
|
} array[31]; /* unknown length */
|
|
};
|
|
|
|
/* blocks pointed to by code_page_directory */
|
|
|
|
#define CP_DATA_MAGIC 0x894521f7
|
|
|
|
struct code_page_data
|
|
{
|
|
unsigned magic; /* 8945 21f7 */
|
|
unsigned n_used; /* # elements used in c_p_data[] */
|
|
unsigned bounds[3]; /* looks a bit like
|
|
(beg1,end1), (beg2,end2)
|
|
one byte each */
|
|
unsigned short offs[3]; /* offsets from start of sector
|
|
to start of c_p_data[ix] */
|
|
struct {
|
|
unsigned short ix; /* index */
|
|
unsigned short code_page_number; /* code page number */
|
|
unsigned short unknown; /* the same as in cp directory */
|
|
unsigned char map[128]; /* upcase table for chars 80..ff */
|
|
unsigned short zero2;
|
|
} code_page[3];
|
|
unsigned char incognita[78];
|
|
};
|
|
|
|
|
|
/* Free space bitmaps are 4 sectors long, which is 16384 bits.
|
|
16384 sectors is 8 meg, and each 8 meg band has a 4-sector bitmap.
|
|
Bit order in the maps is little-endian. 0 means taken, 1 means free.
|
|
|
|
Bit map sectors are marked allocated in the bit maps, and so are sectors
|
|
off the end of the partition.
|
|
|
|
Band 0 is sectors 0-3fff, its map is in sectors 18-1b.
|
|
Band 1 is 4000-7fff, its map is in 7ffc-7fff.
|
|
Band 2 is 8000-ffff, its map is in 8000-8003.
|
|
The remaining bands have maps in their first (even) or last (odd) 4 sectors
|
|
-- if the last, partial, band is odd its map is in its last 4 sectors.
|
|
|
|
The bitmap locations are given in a table pointed to by the super block.
|
|
No doubt they aren't constrained to be at 18, 7ffc, 8000, ...; that is
|
|
just where they usually are.
|
|
|
|
The "directory band" is a bunch of sectors preallocated for dnodes.
|
|
It has a 4-sector free space bitmap of its own. Each bit in the map
|
|
corresponds to one 4-sector dnode, bit 0 of the map corresponding to
|
|
the first 4 sectors of the directory band. The entire band is marked
|
|
allocated in the main bitmap. The super block gives the locations
|
|
of the directory band and its bitmap. ("band" doesn't mean it is
|
|
8 meg long; it isn't.) */
|
|
|
|
|
|
/* dnode: directory. 4 sectors long */
|
|
|
|
/* A directory is a tree of dnodes. The fnode for a directory
|
|
contains one pointer, to the root dnode of the tree. The fnode
|
|
never moves, the dnodes do the B-tree thing, splitting and merging
|
|
as files are added and removed. */
|
|
|
|
#define DNODE_MAGIC 0x77e40aae
|
|
|
|
struct dnode {
|
|
unsigned magic; /* 77e4 0aae */
|
|
unsigned first_free; /* offset from start of dnode to
|
|
first free dir entry */
|
|
unsigned root_dnode:1; /* Is it root dnode? */
|
|
unsigned increment_me:31; /* some kind of activity counter?
|
|
Neither HPFS.IFS nor CHKDSK cares
|
|
if you change this word */
|
|
secno up; /* (root dnode) directory's fnode
|
|
(nonroot) parent dnode */
|
|
dnode_secno self; /* pointer to this dnode */
|
|
unsigned char dirent[2028]; /* one or more dirents */
|
|
};
|
|
|
|
struct hpfs_dirent {
|
|
unsigned short length; /* offset to next dirent */
|
|
unsigned first: 1; /* set on phony ^A^A (".") entry */
|
|
unsigned has_acl: 1;
|
|
unsigned down: 1; /* down pointer present (after name) */
|
|
unsigned last: 1; /* set on phony \377 entry */
|
|
unsigned has_ea: 1; /* entry has EA */
|
|
unsigned has_xtd_perm: 1; /* has extended perm list (???) */
|
|
unsigned has_explicit_acl: 1;
|
|
unsigned has_needea: 1; /* ?? some EA has NEEDEA set
|
|
I have no idea why this is
|
|
interesting in a dir entry */
|
|
unsigned read_only: 1; /* dos attrib */
|
|
unsigned hidden: 1; /* dos attrib */
|
|
unsigned system: 1; /* dos attrib */
|
|
unsigned flag11: 1; /* would be volume label dos attrib */
|
|
unsigned directory: 1; /* dos attrib */
|
|
unsigned archive: 1; /* dos attrib */
|
|
unsigned not_8x3: 1; /* name is not 8.3 */
|
|
unsigned flag15: 1;
|
|
fnode_secno fnode; /* fnode giving allocation info */
|
|
time32_t write_date; /* mtime */
|
|
unsigned file_size; /* file length, bytes */
|
|
time32_t read_date; /* atime */
|
|
time32_t creation_date; /* ctime */
|
|
unsigned ea_size; /* total EA length, bytes */
|
|
unsigned char no_of_acls : 3; /* number of ACL's */
|
|
unsigned char reserver : 5;
|
|
unsigned char ix; /* code page index (of filename), see
|
|
struct code_page_data */
|
|
unsigned char namelen, name[1]; /* file name */
|
|
/* dnode_secno down; btree down pointer, if present,
|
|
follows name on next word boundary, or maybe it
|
|
precedes next dirent, which is on a word boundary. */
|
|
};
|
|
|
|
|
|
/* B+ tree: allocation info in fnodes and anodes */
|
|
|
|
/* dnodes point to fnodes which are responsible for listing the sectors
|
|
assigned to the file. This is done with trees of (length,address)
|
|
pairs. (Actually triples, of (length, file-address, disk-address)
|
|
which can represent holes. Find out if HPFS does that.)
|
|
At any rate, fnodes contain a small tree; if subtrees are needed
|
|
they occupy essentially a full block in anodes. A leaf-level tree node
|
|
has 3-word entries giving sector runs, a non-leaf node has 2-word
|
|
entries giving subtree pointers. A flag in the header says which. */
|
|
|
|
struct bplus_leaf_node
|
|
{
|
|
unsigned file_secno; /* first file sector in extent */
|
|
unsigned length; /* length, sectors */
|
|
secno disk_secno; /* first corresponding disk sector */
|
|
};
|
|
|
|
struct bplus_internal_node
|
|
{
|
|
unsigned file_secno; /* subtree maps sectors < this */
|
|
anode_secno down; /* pointer to subtree */
|
|
};
|
|
|
|
struct bplus_header
|
|
{
|
|
unsigned hbff: 1; /* high bit of first free entry offset */
|
|
unsigned flag1: 1;
|
|
unsigned flag2: 1;
|
|
unsigned flag3: 1;
|
|
unsigned flag4: 1;
|
|
unsigned fnode_parent: 1; /* ? we're pointed to by an fnode,
|
|
the data btree or some ea or the
|
|
main ea bootage pointer ea_secno */
|
|
/* also can get set in fnodes, which
|
|
may be a chkdsk glitch or may mean
|
|
this bit is irrelevant in fnodes,
|
|
or this interpretation is all wet */
|
|
unsigned binary_search: 1; /* suggest binary search (unused) */
|
|
unsigned internal: 1; /* 1 -> (internal) tree of anodes
|
|
0 -> (leaf) list of extents */
|
|
unsigned char fill[3];
|
|
unsigned char n_free_nodes; /* free nodes in following array */
|
|
unsigned char n_used_nodes; /* used nodes in following array */
|
|
unsigned short first_free; /* offset from start of header to
|
|
first free node in array */
|
|
union {
|
|
struct bplus_internal_node internal[0]; /* (internal) 2-word entries giving
|
|
subtree pointers */
|
|
struct bplus_leaf_node external[0]; /* (external) 3-word entries giving
|
|
sector runs */
|
|
} u;
|
|
};
|
|
|
|
/* fnode: root of allocation b+ tree, and EA's */
|
|
|
|
/* Every file and every directory has one fnode, pointed to by the directory
|
|
entry and pointing to the file's sectors or directory's root dnode. EA's
|
|
are also stored here, and there are said to be ACL's somewhere here too. */
|
|
|
|
#define FNODE_MAGIC 0xf7e40aae
|
|
|
|
struct fnode
|
|
{
|
|
unsigned magic; /* f7e4 0aae */
|
|
unsigned zero1[2]; /* read history */
|
|
unsigned char len, name[15]; /* true length, truncated name */
|
|
fnode_secno up; /* pointer to file's directory fnode */
|
|
/*unsigned zero2[3];*/
|
|
secno acl_size_l;
|
|
secno acl_secno;
|
|
unsigned short acl_size_s;
|
|
char acl_anode;
|
|
char zero2; /* history bit count */
|
|
unsigned ea_size_l; /* length of disk-resident ea's */
|
|
secno ea_secno; /* first sector of disk-resident ea's*/
|
|
unsigned short ea_size_s; /* length of fnode-resident ea's */
|
|
|
|
unsigned flag0: 1;
|
|
unsigned ea_anode: 1; /* 1 -> ea_secno is an anode */
|
|
unsigned flag2: 1;
|
|
unsigned flag3: 1;
|
|
unsigned flag4: 1;
|
|
unsigned flag5: 1;
|
|
unsigned flag6: 1;
|
|
unsigned flag7: 1;
|
|
unsigned dirflag: 1; /* 1 -> directory. first & only extent
|
|
points to dnode. */
|
|
unsigned flag9: 1;
|
|
unsigned flag10: 1;
|
|
unsigned flag11: 1;
|
|
unsigned flag12: 1;
|
|
unsigned flag13: 1;
|
|
unsigned flag14: 1;
|
|
unsigned flag15: 1;
|
|
|
|
struct bplus_header btree; /* b+ tree, 8 extents or 12 subtrees */
|
|
union {
|
|
struct bplus_leaf_node external[8];
|
|
struct bplus_internal_node internal[12];
|
|
} u;
|
|
|
|
unsigned file_size; /* file length, bytes */
|
|
unsigned n_needea; /* number of EA's with NEEDEA set */
|
|
char user_id[16]; /* unused */
|
|
unsigned short ea_offs; /* offset from start of fnode
|
|
to first fnode-resident ea */
|
|
char dasd_limit_treshhold;
|
|
char dasd_limit_delta;
|
|
unsigned dasd_limit;
|
|
unsigned dasd_usage;
|
|
/*unsigned zero5[2];*/
|
|
unsigned char ea[316]; /* zero or more EA's, packed together
|
|
with no alignment padding.
|
|
(Do not use this name, get here
|
|
via fnode + ea_offs. I think.) */
|
|
};
|
|
|
|
|
|
/* anode: 99.44% pure allocation tree */
|
|
|
|
#define ANODE_MAGIC 0x37e40aae
|
|
|
|
struct anode
|
|
{
|
|
unsigned magic; /* 37e4 0aae */
|
|
anode_secno self; /* pointer to this anode */
|
|
secno up; /* parent anode or fnode */
|
|
|
|
struct bplus_header btree; /* b+tree, 40 extents or 60 subtrees */
|
|
union {
|
|
struct bplus_leaf_node external[40];
|
|
struct bplus_internal_node internal[60];
|
|
} u;
|
|
|
|
unsigned fill[3]; /* unused */
|
|
};
|
|
|
|
|
|
/* extended attributes.
|
|
|
|
A file's EA info is stored as a list of (name,value) pairs. It is
|
|
usually in the fnode, but (if it's large) it is moved to a single
|
|
sector run outside the fnode, or to multiple runs with an anode tree
|
|
that points to them.
|
|
|
|
The value of a single EA is stored along with the name, or (if large)
|
|
it is moved to a single sector run, or multiple runs pointed to by an
|
|
anode tree, pointed to by the value field of the (name,value) pair.
|
|
|
|
Flags in the EA tell whether the value is immediate, in a single sector
|
|
run, or in multiple runs. Flags in the fnode tell whether the EA list
|
|
is immediate, in a single run, or in multiple runs. */
|
|
|
|
struct extended_attribute
|
|
{
|
|
unsigned indirect: 1; /* 1 -> value gives sector number
|
|
where real value starts */
|
|
unsigned anode: 1; /* 1 -> sector is an anode
|
|
that points to fragmented value */
|
|
unsigned flag2: 1;
|
|
unsigned flag3: 1;
|
|
unsigned flag4: 1;
|
|
unsigned flag5: 1;
|
|
unsigned flag6: 1;
|
|
unsigned needea: 1; /* required ea */
|
|
unsigned char namelen; /* length of name, bytes */
|
|
unsigned short valuelen; /* length of value, bytes */
|
|
unsigned char name[0];
|
|
/*
|
|
unsigned char name[namelen]; ascii attrib name
|
|
unsigned char nul; terminating '\0', not counted
|
|
unsigned char value[valuelen]; value, arbitrary
|
|
if this.indirect, valuelen is 8 and the value is
|
|
unsigned length; real length of value, bytes
|
|
secno secno; sector address where it starts
|
|
if this.anode, the above sector number is the root of an anode tree
|
|
which points to the value.
|
|
*/
|
|
};
|
|
|
|
/*
|
|
Local Variables:
|
|
comment-column: 40
|
|
End:
|
|
*/
|