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- /* SPDX-License-Identifier: GPL-2.0 */
- #ifndef __LINUX_BITMAP_H
- #define __LINUX_BITMAP_H
- #ifndef __ASSEMBLY__
- #include <linux/align.h>
- #include <linux/bitops.h>
- #include <linux/find.h>
- #include <linux/limits.h>
- #include <linux/string.h>
- #include <linux/types.h>
- struct device;
- /*
- * bitmaps provide bit arrays that consume one or more unsigned
- * longs. The bitmap interface and available operations are listed
- * here, in bitmap.h
- *
- * Function implementations generic to all architectures are in
- * lib/bitmap.c. Functions implementations that are architecture
- * specific are in various include/asm-<arch>/bitops.h headers
- * and other arch/<arch> specific files.
- *
- * See lib/bitmap.c for more details.
- */
- /**
- * DOC: bitmap overview
- *
- * The available bitmap operations and their rough meaning in the
- * case that the bitmap is a single unsigned long are thus:
- *
- * The generated code is more efficient when nbits is known at
- * compile-time and at most BITS_PER_LONG.
- *
- * ::
- *
- * bitmap_zero(dst, nbits) *dst = 0UL
- * bitmap_fill(dst, nbits) *dst = ~0UL
- * bitmap_copy(dst, src, nbits) *dst = *src
- * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2
- * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2
- * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2
- * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2)
- * bitmap_complement(dst, src, nbits) *dst = ~(*src)
- * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal?
- * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap?
- * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2?
- * bitmap_empty(src, nbits) Are all bits zero in *src?
- * bitmap_full(src, nbits) Are all bits set in *src?
- * bitmap_weight(src, nbits) Hamming Weight: number set bits
- * bitmap_weight_and(src1, src2, nbits) Hamming Weight of and'ed bitmap
- * bitmap_set(dst, pos, nbits) Set specified bit area
- * bitmap_clear(dst, pos, nbits) Clear specified bit area
- * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area
- * bitmap_find_next_zero_area_off(buf, len, pos, n, mask, mask_off) as above
- * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n
- * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n
- * bitmap_cut(dst, src, first, n, nbits) Cut n bits from first, copy rest
- * bitmap_replace(dst, old, new, mask, nbits) *dst = (*old & ~(*mask)) | (*new & *mask)
- * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src)
- * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit)
- * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap
- * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz
- * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf
- * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf
- * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf
- * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf
- * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region
- * bitmap_release_region(bitmap, pos, order) Free specified bit region
- * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region
- * bitmap_from_arr32(dst, buf, nbits) Copy nbits from u32[] buf to dst
- * bitmap_from_arr64(dst, buf, nbits) Copy nbits from u64[] buf to dst
- * bitmap_to_arr32(buf, src, nbits) Copy nbits from buf to u32[] dst
- * bitmap_to_arr64(buf, src, nbits) Copy nbits from buf to u64[] dst
- * bitmap_get_value8(map, start) Get 8bit value from map at start
- * bitmap_set_value8(map, value, start) Set 8bit value to map at start
- *
- * Note, bitmap_zero() and bitmap_fill() operate over the region of
- * unsigned longs, that is, bits behind bitmap till the unsigned long
- * boundary will be zeroed or filled as well. Consider to use
- * bitmap_clear() or bitmap_set() to make explicit zeroing or filling
- * respectively.
- */
- /**
- * DOC: bitmap bitops
- *
- * Also the following operations in asm/bitops.h apply to bitmaps.::
- *
- * set_bit(bit, addr) *addr |= bit
- * clear_bit(bit, addr) *addr &= ~bit
- * change_bit(bit, addr) *addr ^= bit
- * test_bit(bit, addr) Is bit set in *addr?
- * test_and_set_bit(bit, addr) Set bit and return old value
- * test_and_clear_bit(bit, addr) Clear bit and return old value
- * test_and_change_bit(bit, addr) Change bit and return old value
- * find_first_zero_bit(addr, nbits) Position first zero bit in *addr
- * find_first_bit(addr, nbits) Position first set bit in *addr
- * find_next_zero_bit(addr, nbits, bit)
- * Position next zero bit in *addr >= bit
- * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit
- * find_next_and_bit(addr1, addr2, nbits, bit)
- * Same as find_next_bit, but in
- * (*addr1 & *addr2)
- *
- */
- /**
- * DOC: declare bitmap
- * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used
- * to declare an array named 'name' of just enough unsigned longs to
- * contain all bit positions from 0 to 'bits' - 1.
- */
- /*
- * Allocation and deallocation of bitmap.
- * Provided in lib/bitmap.c to avoid circular dependency.
- */
- unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags);
- unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags);
- unsigned long *bitmap_alloc_node(unsigned int nbits, gfp_t flags, int node);
- unsigned long *bitmap_zalloc_node(unsigned int nbits, gfp_t flags, int node);
- void bitmap_free(const unsigned long *bitmap);
- /* Managed variants of the above. */
- unsigned long *devm_bitmap_alloc(struct device *dev,
- unsigned int nbits, gfp_t flags);
- unsigned long *devm_bitmap_zalloc(struct device *dev,
- unsigned int nbits, gfp_t flags);
- /*
- * lib/bitmap.c provides these functions:
- */
- bool __bitmap_equal(const unsigned long *bitmap1,
- const unsigned long *bitmap2, unsigned int nbits);
- bool __pure __bitmap_or_equal(const unsigned long *src1,
- const unsigned long *src2,
- const unsigned long *src3,
- unsigned int nbits);
- void __bitmap_complement(unsigned long *dst, const unsigned long *src,
- unsigned int nbits);
- void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
- unsigned int shift, unsigned int nbits);
- void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
- unsigned int shift, unsigned int nbits);
- void bitmap_cut(unsigned long *dst, const unsigned long *src,
- unsigned int first, unsigned int cut, unsigned int nbits);
- bool __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
- const unsigned long *bitmap2, unsigned int nbits);
- void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
- const unsigned long *bitmap2, unsigned int nbits);
- void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
- const unsigned long *bitmap2, unsigned int nbits);
- bool __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
- const unsigned long *bitmap2, unsigned int nbits);
- void __bitmap_replace(unsigned long *dst,
- const unsigned long *old, const unsigned long *new,
- const unsigned long *mask, unsigned int nbits);
- bool __bitmap_intersects(const unsigned long *bitmap1,
- const unsigned long *bitmap2, unsigned int nbits);
- bool __bitmap_subset(const unsigned long *bitmap1,
- const unsigned long *bitmap2, unsigned int nbits);
- unsigned int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
- unsigned int __bitmap_weight_and(const unsigned long *bitmap1,
- const unsigned long *bitmap2, unsigned int nbits);
- void __bitmap_set(unsigned long *map, unsigned int start, int len);
- void __bitmap_clear(unsigned long *map, unsigned int start, int len);
- unsigned long bitmap_find_next_zero_area_off(unsigned long *map,
- unsigned long size,
- unsigned long start,
- unsigned int nr,
- unsigned long align_mask,
- unsigned long align_offset);
- /**
- * bitmap_find_next_zero_area - find a contiguous aligned zero area
- * @map: The address to base the search on
- * @size: The bitmap size in bits
- * @start: The bitnumber to start searching at
- * @nr: The number of zeroed bits we're looking for
- * @align_mask: Alignment mask for zero area
- *
- * The @align_mask should be one less than a power of 2; the effect is that
- * the bit offset of all zero areas this function finds is multiples of that
- * power of 2. A @align_mask of 0 means no alignment is required.
- */
- static inline unsigned long
- bitmap_find_next_zero_area(unsigned long *map,
- unsigned long size,
- unsigned long start,
- unsigned int nr,
- unsigned long align_mask)
- {
- return bitmap_find_next_zero_area_off(map, size, start, nr,
- align_mask, 0);
- }
- int bitmap_parse(const char *buf, unsigned int buflen,
- unsigned long *dst, int nbits);
- int bitmap_parse_user(const char __user *ubuf, unsigned int ulen,
- unsigned long *dst, int nbits);
- int bitmap_parselist(const char *buf, unsigned long *maskp,
- int nmaskbits);
- int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen,
- unsigned long *dst, int nbits);
- void bitmap_remap(unsigned long *dst, const unsigned long *src,
- const unsigned long *old, const unsigned long *new, unsigned int nbits);
- int bitmap_bitremap(int oldbit,
- const unsigned long *old, const unsigned long *new, int bits);
- void bitmap_onto(unsigned long *dst, const unsigned long *orig,
- const unsigned long *relmap, unsigned int bits);
- void bitmap_fold(unsigned long *dst, const unsigned long *orig,
- unsigned int sz, unsigned int nbits);
- int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
- void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
- int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
- #ifdef __BIG_ENDIAN
- void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
- #else
- #define bitmap_copy_le bitmap_copy
- #endif
- int bitmap_print_to_pagebuf(bool list, char *buf,
- const unsigned long *maskp, int nmaskbits);
- extern int bitmap_print_bitmask_to_buf(char *buf, const unsigned long *maskp,
- int nmaskbits, loff_t off, size_t count);
- extern int bitmap_print_list_to_buf(char *buf, const unsigned long *maskp,
- int nmaskbits, loff_t off, size_t count);
- #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1)))
- #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1)))
- static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
- {
- unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
- if (small_const_nbits(nbits))
- *dst = 0;
- else
- memset(dst, 0, len);
- }
- static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
- {
- unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
- if (small_const_nbits(nbits))
- *dst = ~0UL;
- else
- memset(dst, 0xff, len);
- }
- static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
- unsigned int nbits)
- {
- unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
- if (small_const_nbits(nbits))
- *dst = *src;
- else
- memcpy(dst, src, len);
- }
- /*
- * Copy bitmap and clear tail bits in last word.
- */
- static inline void bitmap_copy_clear_tail(unsigned long *dst,
- const unsigned long *src, unsigned int nbits)
- {
- bitmap_copy(dst, src, nbits);
- if (nbits % BITS_PER_LONG)
- dst[nbits / BITS_PER_LONG] &= BITMAP_LAST_WORD_MASK(nbits);
- }
- /*
- * On 32-bit systems bitmaps are represented as u32 arrays internally. On LE64
- * machines the order of hi and lo parts of numbers match the bitmap structure.
- * In both cases conversion is not needed when copying data from/to arrays of
- * u32. But in LE64 case, typecast in bitmap_copy_clear_tail() may lead
- * to out-of-bound access. To avoid that, both LE and BE variants of 64-bit
- * architectures are not using bitmap_copy_clear_tail().
- */
- #if BITS_PER_LONG == 64
- void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf,
- unsigned int nbits);
- void bitmap_to_arr32(u32 *buf, const unsigned long *bitmap,
- unsigned int nbits);
- #else
- #define bitmap_from_arr32(bitmap, buf, nbits) \
- bitmap_copy_clear_tail((unsigned long *) (bitmap), \
- (const unsigned long *) (buf), (nbits))
- #define bitmap_to_arr32(buf, bitmap, nbits) \
- bitmap_copy_clear_tail((unsigned long *) (buf), \
- (const unsigned long *) (bitmap), (nbits))
- #endif
- /*
- * On 64-bit systems bitmaps are represented as u64 arrays internally. So,
- * the conversion is not needed when copying data from/to arrays of u64.
- */
- #if BITS_PER_LONG == 32
- void bitmap_from_arr64(unsigned long *bitmap, const u64 *buf, unsigned int nbits);
- void bitmap_to_arr64(u64 *buf, const unsigned long *bitmap, unsigned int nbits);
- #else
- #define bitmap_from_arr64(bitmap, buf, nbits) \
- bitmap_copy_clear_tail((unsigned long *)(bitmap), (const unsigned long *)(buf), (nbits))
- #define bitmap_to_arr64(buf, bitmap, nbits) \
- bitmap_copy_clear_tail((unsigned long *)(buf), (const unsigned long *)(bitmap), (nbits))
- #endif
- static inline bool bitmap_and(unsigned long *dst, const unsigned long *src1,
- const unsigned long *src2, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0;
- return __bitmap_and(dst, src1, src2, nbits);
- }
- static inline void bitmap_or(unsigned long *dst, const unsigned long *src1,
- const unsigned long *src2, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- *dst = *src1 | *src2;
- else
- __bitmap_or(dst, src1, src2, nbits);
- }
- static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1,
- const unsigned long *src2, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- *dst = *src1 ^ *src2;
- else
- __bitmap_xor(dst, src1, src2, nbits);
- }
- static inline bool bitmap_andnot(unsigned long *dst, const unsigned long *src1,
- const unsigned long *src2, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
- return __bitmap_andnot(dst, src1, src2, nbits);
- }
- static inline void bitmap_complement(unsigned long *dst, const unsigned long *src,
- unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- *dst = ~(*src);
- else
- __bitmap_complement(dst, src, nbits);
- }
- #ifdef __LITTLE_ENDIAN
- #define BITMAP_MEM_ALIGNMENT 8
- #else
- #define BITMAP_MEM_ALIGNMENT (8 * sizeof(unsigned long))
- #endif
- #define BITMAP_MEM_MASK (BITMAP_MEM_ALIGNMENT - 1)
- static inline bool bitmap_equal(const unsigned long *src1,
- const unsigned long *src2, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- return !((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits));
- if (__builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
- IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
- return !memcmp(src1, src2, nbits / 8);
- return __bitmap_equal(src1, src2, nbits);
- }
- /**
- * bitmap_or_equal - Check whether the or of two bitmaps is equal to a third
- * @src1: Pointer to bitmap 1
- * @src2: Pointer to bitmap 2 will be or'ed with bitmap 1
- * @src3: Pointer to bitmap 3. Compare to the result of *@src1 | *@src2
- * @nbits: number of bits in each of these bitmaps
- *
- * Returns: True if (*@src1 | *@src2) == *@src3, false otherwise
- */
- static inline bool bitmap_or_equal(const unsigned long *src1,
- const unsigned long *src2,
- const unsigned long *src3,
- unsigned int nbits)
- {
- if (!small_const_nbits(nbits))
- return __bitmap_or_equal(src1, src2, src3, nbits);
- return !(((*src1 | *src2) ^ *src3) & BITMAP_LAST_WORD_MASK(nbits));
- }
- static inline bool bitmap_intersects(const unsigned long *src1,
- const unsigned long *src2,
- unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0;
- else
- return __bitmap_intersects(src1, src2, nbits);
- }
- static inline bool bitmap_subset(const unsigned long *src1,
- const unsigned long *src2, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits));
- else
- return __bitmap_subset(src1, src2, nbits);
- }
- static inline bool bitmap_empty(const unsigned long *src, unsigned nbits)
- {
- if (small_const_nbits(nbits))
- return ! (*src & BITMAP_LAST_WORD_MASK(nbits));
- return find_first_bit(src, nbits) == nbits;
- }
- static inline bool bitmap_full(const unsigned long *src, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits));
- return find_first_zero_bit(src, nbits) == nbits;
- }
- static __always_inline
- unsigned int bitmap_weight(const unsigned long *src, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits));
- return __bitmap_weight(src, nbits);
- }
- static __always_inline
- unsigned long bitmap_weight_and(const unsigned long *src1,
- const unsigned long *src2, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- return hweight_long(*src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits));
- return __bitmap_weight_and(src1, src2, nbits);
- }
- static __always_inline void bitmap_set(unsigned long *map, unsigned int start,
- unsigned int nbits)
- {
- if (__builtin_constant_p(nbits) && nbits == 1)
- __set_bit(start, map);
- else if (small_const_nbits(start + nbits))
- *map |= GENMASK(start + nbits - 1, start);
- else if (__builtin_constant_p(start & BITMAP_MEM_MASK) &&
- IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) &&
- __builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
- IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
- memset((char *)map + start / 8, 0xff, nbits / 8);
- else
- __bitmap_set(map, start, nbits);
- }
- static __always_inline void bitmap_clear(unsigned long *map, unsigned int start,
- unsigned int nbits)
- {
- if (__builtin_constant_p(nbits) && nbits == 1)
- __clear_bit(start, map);
- else if (small_const_nbits(start + nbits))
- *map &= ~GENMASK(start + nbits - 1, start);
- else if (__builtin_constant_p(start & BITMAP_MEM_MASK) &&
- IS_ALIGNED(start, BITMAP_MEM_ALIGNMENT) &&
- __builtin_constant_p(nbits & BITMAP_MEM_MASK) &&
- IS_ALIGNED(nbits, BITMAP_MEM_ALIGNMENT))
- memset((char *)map + start / 8, 0, nbits / 8);
- else
- __bitmap_clear(map, start, nbits);
- }
- static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src,
- unsigned int shift, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift;
- else
- __bitmap_shift_right(dst, src, shift, nbits);
- }
- static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src,
- unsigned int shift, unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits);
- else
- __bitmap_shift_left(dst, src, shift, nbits);
- }
- static inline void bitmap_replace(unsigned long *dst,
- const unsigned long *old,
- const unsigned long *new,
- const unsigned long *mask,
- unsigned int nbits)
- {
- if (small_const_nbits(nbits))
- *dst = (*old & ~(*mask)) | (*new & *mask);
- else
- __bitmap_replace(dst, old, new, mask, nbits);
- }
- static inline void bitmap_next_set_region(unsigned long *bitmap,
- unsigned int *rs, unsigned int *re,
- unsigned int end)
- {
- *rs = find_next_bit(bitmap, end, *rs);
- *re = find_next_zero_bit(bitmap, end, *rs + 1);
- }
- /**
- * BITMAP_FROM_U64() - Represent u64 value in the format suitable for bitmap.
- * @n: u64 value
- *
- * Linux bitmaps are internally arrays of unsigned longs, i.e. 32-bit
- * integers in 32-bit environment, and 64-bit integers in 64-bit one.
- *
- * There are four combinations of endianness and length of the word in linux
- * ABIs: LE64, BE64, LE32 and BE32.
- *
- * On 64-bit kernels 64-bit LE and BE numbers are naturally ordered in
- * bitmaps and therefore don't require any special handling.
- *
- * On 32-bit kernels 32-bit LE ABI orders lo word of 64-bit number in memory
- * prior to hi, and 32-bit BE orders hi word prior to lo. The bitmap on the
- * other hand is represented as an array of 32-bit words and the position of
- * bit N may therefore be calculated as: word #(N/32) and bit #(N%32) in that
- * word. For example, bit #42 is located at 10th position of 2nd word.
- * It matches 32-bit LE ABI, and we can simply let the compiler store 64-bit
- * values in memory as it usually does. But for BE we need to swap hi and lo
- * words manually.
- *
- * With all that, the macro BITMAP_FROM_U64() does explicit reordering of hi and
- * lo parts of u64. For LE32 it does nothing, and for BE environment it swaps
- * hi and lo words, as is expected by bitmap.
- */
- #if __BITS_PER_LONG == 64
- #define BITMAP_FROM_U64(n) (n)
- #else
- #define BITMAP_FROM_U64(n) ((unsigned long) ((u64)(n) & ULONG_MAX)), \
- ((unsigned long) ((u64)(n) >> 32))
- #endif
- /**
- * bitmap_from_u64 - Check and swap words within u64.
- * @mask: source bitmap
- * @dst: destination bitmap
- *
- * In 32-bit Big Endian kernel, when using ``(u32 *)(&val)[*]``
- * to read u64 mask, we will get the wrong word.
- * That is ``(u32 *)(&val)[0]`` gets the upper 32 bits,
- * but we expect the lower 32-bits of u64.
- */
- static inline void bitmap_from_u64(unsigned long *dst, u64 mask)
- {
- bitmap_from_arr64(dst, &mask, 64);
- }
- /**
- * bitmap_get_value8 - get an 8-bit value within a memory region
- * @map: address to the bitmap memory region
- * @start: bit offset of the 8-bit value; must be a multiple of 8
- *
- * Returns the 8-bit value located at the @start bit offset within the @src
- * memory region.
- */
- static inline unsigned long bitmap_get_value8(const unsigned long *map,
- unsigned long start)
- {
- const size_t index = BIT_WORD(start);
- const unsigned long offset = start % BITS_PER_LONG;
- return (map[index] >> offset) & 0xFF;
- }
- /**
- * bitmap_set_value8 - set an 8-bit value within a memory region
- * @map: address to the bitmap memory region
- * @value: the 8-bit value; values wider than 8 bits may clobber bitmap
- * @start: bit offset of the 8-bit value; must be a multiple of 8
- */
- static inline void bitmap_set_value8(unsigned long *map, unsigned long value,
- unsigned long start)
- {
- const size_t index = BIT_WORD(start);
- const unsigned long offset = start % BITS_PER_LONG;
- map[index] &= ~(0xFFUL << offset);
- map[index] |= value << offset;
- }
- #endif /* __ASSEMBLY__ */
- #endif /* __LINUX_BITMAP_H */
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