busybox/e2fsprogs/ext2fs/bitops.h
2005-05-09 22:10:42 +00:00

618 lines
16 KiB
C

/*
* bitops.h --- Bitmap frobbing code. The byte swapping routines are
* also included here.
*
* Copyright (C) 1993, 1994, 1995, 1996 Theodore Ts'o.
*
* %Begin-Header%
* This file may be redistributed under the terms of the GNU Public
* License.
* %End-Header%
*
* i386 bitops operations taken from <asm/bitops.h>, Copyright 1992,
* Linus Torvalds.
*/
extern int ext2fs_set_bit(int nr,void * addr);
extern int ext2fs_clear_bit(int nr, void * addr);
extern int ext2fs_test_bit(int nr, const void * addr);
extern __u16 ext2fs_swab16(__u16 val);
extern __u32 ext2fs_swab32(__u32 val);
#ifdef WORDS_BIGENDIAN
#define ext2fs_cpu_to_le32(x) ext2fs_swab32((x))
#define ext2fs_le32_to_cpu(x) ext2fs_swab32((x))
#define ext2fs_cpu_to_le16(x) ext2fs_swab16((x))
#define ext2fs_le16_to_cpu(x) ext2fs_swab16((x))
#define ext2fs_cpu_to_be32(x) ((__u32)(x))
#define ext2fs_be32_to_cpu(x) ((__u32)(x))
#define ext2fs_cpu_to_be16(x) ((__u16)(x))
#define ext2fs_be16_to_cpu(x) ((__u16)(x))
#else
#define ext2fs_cpu_to_le32(x) ((__u32)(x))
#define ext2fs_le32_to_cpu(x) ((__u32)(x))
#define ext2fs_cpu_to_le16(x) ((__u16)(x))
#define ext2fs_le16_to_cpu(x) ((__u16)(x))
#define ext2fs_cpu_to_be32(x) ext2fs_swab32((x))
#define ext2fs_be32_to_cpu(x) ext2fs_swab32((x))
#define ext2fs_cpu_to_be16(x) ext2fs_swab16((x))
#define ext2fs_be16_to_cpu(x) ext2fs_swab16((x))
#endif
/*
* EXT2FS bitmap manipulation routines.
*/
/* Support for sending warning messages from the inline subroutines */
extern const char *ext2fs_block_string;
extern const char *ext2fs_inode_string;
extern const char *ext2fs_mark_string;
extern const char *ext2fs_unmark_string;
extern const char *ext2fs_test_string;
extern void ext2fs_warn_bitmap(errcode_t errcode, unsigned long arg,
const char *description);
extern void ext2fs_warn_bitmap2(ext2fs_generic_bitmap bitmap,
int code, unsigned long arg);
extern int ext2fs_mark_block_bitmap(ext2fs_block_bitmap bitmap, blk_t block);
extern int ext2fs_unmark_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block);
extern int ext2fs_test_block_bitmap(ext2fs_block_bitmap bitmap, blk_t block);
extern int ext2fs_mark_inode_bitmap(ext2fs_inode_bitmap bitmap, ext2_ino_t inode);
extern int ext2fs_unmark_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode);
extern int ext2fs_test_inode_bitmap(ext2fs_inode_bitmap bitmap, ext2_ino_t inode);
extern void ext2fs_fast_mark_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block);
extern void ext2fs_fast_unmark_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block);
extern int ext2fs_fast_test_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block);
extern void ext2fs_fast_mark_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode);
extern void ext2fs_fast_unmark_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode);
extern int ext2fs_fast_test_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode);
extern blk_t ext2fs_get_block_bitmap_start(ext2fs_block_bitmap bitmap);
extern ext2_ino_t ext2fs_get_inode_bitmap_start(ext2fs_inode_bitmap bitmap);
extern blk_t ext2fs_get_block_bitmap_end(ext2fs_block_bitmap bitmap);
extern ext2_ino_t ext2fs_get_inode_bitmap_end(ext2fs_inode_bitmap bitmap);
extern void ext2fs_mark_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num);
extern void ext2fs_unmark_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num);
extern int ext2fs_test_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num);
extern void ext2fs_fast_mark_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num);
extern void ext2fs_fast_unmark_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num);
extern int ext2fs_fast_test_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num);
extern void ext2fs_set_bitmap_padding(ext2fs_generic_bitmap map);
/* These two routines moved to gen_bitmap.c */
extern int ext2fs_mark_generic_bitmap(ext2fs_generic_bitmap bitmap,
__u32 bitno);
extern int ext2fs_unmark_generic_bitmap(ext2fs_generic_bitmap bitmap,
blk_t bitno);
/*
* The inline routines themselves...
*
* If NO_INLINE_FUNCS is defined, then we won't try to do inline
* functions at all; they will be included as normal functions in
* inline.c
*/
#ifdef NO_INLINE_FUNCS
#if (defined(__GNUC__) && (defined(__i386__) || defined(__i486__) || \
defined(__i586__) || defined(__mc68000__) || \
defined(__sparc__)))
/* This prevents bitops.c from trying to include the C */
/* function version of these functions */
#define _EXT2_HAVE_ASM_BITOPS_
#endif
#endif /* NO_INLINE_FUNCS */
#if (defined(INCLUDE_INLINE_FUNCS) || !defined(NO_INLINE_FUNCS))
#ifdef INCLUDE_INLINE_FUNCS
#define _INLINE_ extern
#else
#ifdef __GNUC__
#define _INLINE_ extern __inline__
#else /* For Watcom C */
#define _INLINE_ extern inline
#endif
#endif
#if ((defined __GNUC__) && !defined(_EXT2_USE_C_VERSIONS_) && \
(defined(__i386__) || defined(__i486__) || defined(__i586__)))
#define _EXT2_HAVE_ASM_BITOPS_
#define _EXT2_HAVE_ASM_SWAB_
#define _EXT2_HAVE_ASM_FINDBIT_
/*
* These are done by inline assembly for speed reasons.....
*
* All bitoperations return 0 if the bit was cleared before the
* operation and != 0 if it was not. Bit 0 is the LSB of addr; bit 32
* is the LSB of (addr+1).
*/
/*
* Some hacks to defeat gcc over-optimizations..
*/
struct __dummy_h { unsigned long a[100]; };
#define EXT2FS_ADDR (*(struct __dummy_h *) addr)
#define EXT2FS_CONST_ADDR (*(const struct __dummy_h *) addr)
_INLINE_ int ext2fs_set_bit(int nr, void * addr)
{
int oldbit;
__asm__ __volatile__("btsl %2,%1\n\tsbbl %0,%0"
:"=r" (oldbit),"=m" (EXT2FS_ADDR)
:"r" (nr));
return oldbit;
}
_INLINE_ int ext2fs_clear_bit(int nr, void * addr)
{
int oldbit;
__asm__ __volatile__("btrl %2,%1\n\tsbbl %0,%0"
:"=r" (oldbit),"=m" (EXT2FS_ADDR)
:"r" (nr));
return oldbit;
}
_INLINE_ int ext2fs_test_bit(int nr, const void * addr)
{
int oldbit;
__asm__ __volatile__("btl %2,%1\n\tsbbl %0,%0"
:"=r" (oldbit)
:"m" (EXT2FS_CONST_ADDR),"r" (nr));
return oldbit;
}
#if 0
_INLINE_ int ext2fs_find_first_bit_set(void * addr, unsigned size)
{
int d0, d1, d2;
int res;
if (!size)
return 0;
/* This looks at memory. Mark it volatile to tell gcc not to move it around */
__asm__ __volatile__(
"cld\n\t"
"xorl %%eax,%%eax\n\t"
"xorl %%edx,%%edx\n\t"
"repe; scasl\n\t"
"je 1f\n\t"
"movl -4(%%edi),%%eax\n\t"
"subl $4,%%edi\n\t"
"bsfl %%eax,%%edx\n"
"1:\tsubl %%esi,%%edi\n\t"
"shll $3,%%edi\n\t"
"addl %%edi,%%edx"
:"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
:"1" ((size + 31) >> 5), "2" (addr), "S" (addr));
return res;
}
_INLINE_ int ext2fs_find_next_bit_set (void * addr, int size, int offset)
{
unsigned long * p = ((unsigned long *) addr) + (offset >> 5);
int set = 0, bit = offset & 31, res;
if (bit) {
/*
* Look for zero in first byte
*/
__asm__("bsfl %1,%0\n\t"
"jne 1f\n\t"
"movl $32, %0\n"
"1:"
: "=r" (set)
: "r" (*p >> bit));
if (set < (32 - bit))
return set + offset;
set = 32 - bit;
p++;
}
/*
* No bit found yet, search remaining full bytes for a bit
*/
res = ext2fs_find_first_bit_set(p, size - 32 * (p - (unsigned long *) addr));
return (offset + set + res);
}
#endif
#ifdef EXT2FS_ENABLE_SWAPFS
_INLINE_ __u32 ext2fs_swab32(__u32 val)
{
#ifdef EXT2FS_REQUIRE_486
__asm__("bswap %0" : "=r" (val) : "0" (val));
#else
__asm__("xchgb %b0,%h0\n\t" /* swap lower bytes */
"rorl $16,%0\n\t" /* swap words */
"xchgb %b0,%h0" /* swap higher bytes */
:"=q" (val)
: "0" (val));
#endif
return val;
}
_INLINE_ __u16 ext2fs_swab16(__u16 val)
{
__asm__("xchgb %b0,%h0" /* swap bytes */ \
: "=q" (val) \
: "0" (val)); \
return val;
}
#endif
#undef EXT2FS_ADDR
#endif /* i386 */
#ifdef __mc68000__
#define _EXT2_HAVE_ASM_BITOPS_
_INLINE_ int ext2fs_set_bit(int nr,void * addr)
{
char retval;
__asm__ __volatile__ ("bfset %2@{%1:#1}; sne %0"
: "=d" (retval) : "d" (nr^7), "a" (addr));
return retval;
}
_INLINE_ int ext2fs_clear_bit(int nr, void * addr)
{
char retval;
__asm__ __volatile__ ("bfclr %2@{%1:#1}; sne %0"
: "=d" (retval) : "d" (nr^7), "a" (addr));
return retval;
}
_INLINE_ int ext2fs_test_bit(int nr, const void * addr)
{
char retval;
__asm__ __volatile__ ("bftst %2@{%1:#1}; sne %0"
: "=d" (retval) : "d" (nr^7), "a" (addr));
return retval;
}
#endif /* __mc68000__ */
#if !defined(_EXT2_HAVE_ASM_SWAB_) && defined(EXT2FS_ENABLE_SWAPFS)
_INLINE_ __u16 ext2fs_swab16(__u16 val)
{
return (val >> 8) | (val << 8);
}
_INLINE_ __u32 ext2fs_swab32(__u32 val)
{
return ((val>>24) | ((val>>8)&0xFF00) |
((val<<8)&0xFF0000) | (val<<24));
}
#endif /* !_EXT2_HAVE_ASM_SWAB */
#if !defined(_EXT2_HAVE_ASM_FINDBIT_)
_INLINE_ int ext2fs_find_first_bit_set(void * addr, unsigned size)
{
char *cp = (unsigned char *) addr;
int res = 0, d0;
if (!size)
return 0;
while ((size > res) && (*cp == 0)) {
cp++;
res += 8;
}
d0 = ffs(*cp);
if (d0 == 0)
return size;
return res + d0 - 1;
}
_INLINE_ int ext2fs_find_next_bit_set (void * addr, int size, int offset)
{
unsigned char * p;
int set = 0, bit = offset & 7, res = 0, d0;
res = offset >> 3;
p = ((unsigned char *) addr) + res;
if (bit) {
set = ffs(*p & ~((1 << bit) - 1));
if (set)
return (offset & ~7) + set - 1;
p++;
res += 8;
}
while ((size > res) && (*p == 0)) {
p++;
res += 8;
}
d0 = ffs(*p);
if (d0 == 0)
return size;
return (res + d0 - 1);
}
#endif
_INLINE_ int ext2fs_test_generic_bitmap(ext2fs_generic_bitmap bitmap,
blk_t bitno);
_INLINE_ int ext2fs_test_generic_bitmap(ext2fs_generic_bitmap bitmap,
blk_t bitno)
{
if ((bitno < bitmap->start) || (bitno > bitmap->end)) {
ext2fs_warn_bitmap2(bitmap, EXT2FS_TEST_ERROR, bitno);
return 0;
}
return ext2fs_test_bit(bitno - bitmap->start, bitmap->bitmap);
}
_INLINE_ int ext2fs_mark_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block)
{
return ext2fs_mark_generic_bitmap((ext2fs_generic_bitmap)
bitmap,
block);
}
_INLINE_ int ext2fs_unmark_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block)
{
return ext2fs_unmark_generic_bitmap((ext2fs_generic_bitmap) bitmap,
block);
}
_INLINE_ int ext2fs_test_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block)
{
return ext2fs_test_generic_bitmap((ext2fs_generic_bitmap) bitmap,
block);
}
_INLINE_ int ext2fs_mark_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode)
{
return ext2fs_mark_generic_bitmap((ext2fs_generic_bitmap) bitmap,
inode);
}
_INLINE_ int ext2fs_unmark_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode)
{
return ext2fs_unmark_generic_bitmap((ext2fs_generic_bitmap) bitmap,
inode);
}
_INLINE_ int ext2fs_test_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode)
{
return ext2fs_test_generic_bitmap((ext2fs_generic_bitmap) bitmap,
inode);
}
_INLINE_ void ext2fs_fast_mark_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block)
{
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((block < bitmap->start) || (block > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_MARK, block,
bitmap->description);
return;
}
#endif
ext2fs_set_bit(block - bitmap->start, bitmap->bitmap);
}
_INLINE_ void ext2fs_fast_unmark_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block)
{
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((block < bitmap->start) || (block > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_UNMARK,
block, bitmap->description);
return;
}
#endif
ext2fs_clear_bit(block - bitmap->start, bitmap->bitmap);
}
_INLINE_ int ext2fs_fast_test_block_bitmap(ext2fs_block_bitmap bitmap,
blk_t block)
{
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((block < bitmap->start) || (block > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_TEST,
block, bitmap->description);
return 0;
}
#endif
return ext2fs_test_bit(block - bitmap->start, bitmap->bitmap);
}
_INLINE_ void ext2fs_fast_mark_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode)
{
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((inode < bitmap->start) || (inode > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_INODE_MARK,
inode, bitmap->description);
return;
}
#endif
ext2fs_set_bit(inode - bitmap->start, bitmap->bitmap);
}
_INLINE_ void ext2fs_fast_unmark_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode)
{
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((inode < bitmap->start) || (inode > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_INODE_UNMARK,
inode, bitmap->description);
return;
}
#endif
ext2fs_clear_bit(inode - bitmap->start, bitmap->bitmap);
}
_INLINE_ int ext2fs_fast_test_inode_bitmap(ext2fs_inode_bitmap bitmap,
ext2_ino_t inode)
{
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((inode < bitmap->start) || (inode > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_INODE_TEST,
inode, bitmap->description);
return 0;
}
#endif
return ext2fs_test_bit(inode - bitmap->start, bitmap->bitmap);
}
_INLINE_ blk_t ext2fs_get_block_bitmap_start(ext2fs_block_bitmap bitmap)
{
return bitmap->start;
}
_INLINE_ ext2_ino_t ext2fs_get_inode_bitmap_start(ext2fs_inode_bitmap bitmap)
{
return bitmap->start;
}
_INLINE_ blk_t ext2fs_get_block_bitmap_end(ext2fs_block_bitmap bitmap)
{
return bitmap->end;
}
_INLINE_ ext2_ino_t ext2fs_get_inode_bitmap_end(ext2fs_inode_bitmap bitmap)
{
return bitmap->end;
}
_INLINE_ int ext2fs_test_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num)
{
int i;
if ((block < bitmap->start) || (block+num-1 > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_TEST,
block, bitmap->description);
return 0;
}
for (i=0; i < num; i++) {
if (ext2fs_fast_test_block_bitmap(bitmap, block+i))
return 0;
}
return 1;
}
_INLINE_ int ext2fs_fast_test_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num)
{
int i;
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((block < bitmap->start) || (block+num-1 > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_TEST,
block, bitmap->description);
return 0;
}
#endif
for (i=0; i < num; i++) {
if (ext2fs_fast_test_block_bitmap(bitmap, block+i))
return 0;
}
return 1;
}
_INLINE_ void ext2fs_mark_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num)
{
int i;
if ((block < bitmap->start) || (block+num-1 > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_MARK, block,
bitmap->description);
return;
}
for (i=0; i < num; i++)
ext2fs_set_bit(block + i - bitmap->start, bitmap->bitmap);
}
_INLINE_ void ext2fs_fast_mark_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num)
{
int i;
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((block < bitmap->start) || (block+num-1 > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_MARK, block,
bitmap->description);
return;
}
#endif
for (i=0; i < num; i++)
ext2fs_set_bit(block + i - bitmap->start, bitmap->bitmap);
}
_INLINE_ void ext2fs_unmark_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num)
{
int i;
if ((block < bitmap->start) || (block+num-1 > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_UNMARK, block,
bitmap->description);
return;
}
for (i=0; i < num; i++)
ext2fs_clear_bit(block + i - bitmap->start, bitmap->bitmap);
}
_INLINE_ void ext2fs_fast_unmark_block_bitmap_range(ext2fs_block_bitmap bitmap,
blk_t block, int num)
{
int i;
#ifdef EXT2FS_DEBUG_FAST_OPS
if ((block < bitmap->start) || (block+num-1 > bitmap->end)) {
ext2fs_warn_bitmap(EXT2_ET_BAD_BLOCK_UNMARK, block,
bitmap->description);
return;
}
#endif
for (i=0; i < num; i++)
ext2fs_clear_bit(block + i - bitmap->start, bitmap->bitmap);
}
#undef _INLINE_
#endif