diff options
Diffstat (limited to 'include/linux/bitmap.h')
| -rw-r--r-- | include/linux/bitmap.h | 892 |
1 files changed, 717 insertions, 175 deletions
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h index 7ad634501e48..b0395e4ccf90 100644 --- a/include/linux/bitmap.h +++ b/include/linux/bitmap.h @@ -1,12 +1,20 @@ +/* SPDX-License-Identifier: GPL-2.0 */ #ifndef __LINUX_BITMAP_H #define __LINUX_BITMAP_H #ifndef __ASSEMBLY__ -#include <linux/types.h> +#include <linux/align.h> #include <linux/bitops.h> +#include <linux/cleanup.h> +#include <linux/errno.h> +#include <linux/find.h> +#include <linux/limits.h> #include <linux/string.h> -#include <linux/kernel.h> +#include <linux/types.h> +#include <linux/bitmap-str.h> + +struct device; /* * bitmaps provide bit arrays that consume one or more unsigned @@ -15,188 +23,316 @@ * * 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 + * specific are in various arch/<arch>/include/asm/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: * - * Note that nbits should be always a compile time evaluable constant. - * Otherwise many inlines will generate horrible code. - * - * 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_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_shift_right(dst, src, n, nbits) *dst = *src >> n - * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n - * 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_scnprintf(buf, len, src, nbits) Print bitmap src to buf - * 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_scnlistprintf(buf, len, src, nbits) Print bitmap src as list to 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 + * 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_weighted_or(dst, src1, src2, nbits) *dst = *src1 | *src2. Returns Hamming Weight of dst + * 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_weight_andnot(src1, src2, nbits) Hamming Weight of andnot'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_scatter(dst, src, mask, nbits) *dst = map(dense, sparse)(src) + * bitmap_gather(dst, src, mask, nbits) *dst = map(sparse, dense)(src) + * 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 + * bitmap_read(map, start, nbits) Read an nbits-sized value from + * map at start + * bitmap_write(map, value, start, nbits) Write an nbits-sized 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. */ -/* - * 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 +/** + * 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); + +DEFINE_FREE(bitmap, unsigned long *, if (_T) bitmap_free(_T)) + +/* 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: */ -extern int __bitmap_empty(const unsigned long *bitmap, int bits); -extern int __bitmap_full(const unsigned long *bitmap, int bits); -extern int __bitmap_equal(const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); -extern void __bitmap_complement(unsigned long *dst, const unsigned long *src, - int bits); -extern void __bitmap_shift_right(unsigned long *dst, - const unsigned long *src, int shift, int bits); -extern void __bitmap_shift_left(unsigned long *dst, - const unsigned long *src, int shift, int bits); -extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); -extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); -extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); -extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); -extern int __bitmap_intersects(const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); -extern int __bitmap_subset(const unsigned long *bitmap1, - const unsigned long *bitmap2, int bits); -extern int __bitmap_weight(const unsigned long *bitmap, int bits); - -extern void bitmap_set(unsigned long *map, int i, int len); -extern void bitmap_clear(unsigned long *map, int start, int nr); -extern unsigned long bitmap_find_next_zero_area(unsigned long *map, +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); +unsigned int __bitmap_weighted_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); +unsigned int __bitmap_weight_andnot(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 __always_inline +unsigned long bitmap_find_next_zero_area(unsigned long *map, unsigned long size, unsigned long start, unsigned int nr, - unsigned long align_mask); - -extern int bitmap_scnprintf(char *buf, unsigned int len, - const unsigned long *src, int nbits); -extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user, - unsigned long *dst, int nbits); -extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, - unsigned long *dst, int nbits); -extern int bitmap_scnlistprintf(char *buf, unsigned int len, - const unsigned long *src, int nbits); -extern int bitmap_parselist(const char *buf, unsigned long *maskp, - int nmaskbits); -extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen, - unsigned long *dst, int nbits); -extern void bitmap_remap(unsigned long *dst, const unsigned long *src, - const unsigned long *old, const unsigned long *new, int bits); -extern int bitmap_bitremap(int oldbit, + unsigned long align_mask) +{ + return bitmap_find_next_zero_area_off(map, size, start, nr, + align_mask, 0); +} + +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); -extern void bitmap_onto(unsigned long *dst, const unsigned long *orig, - const unsigned long *relmap, int bits); -extern void bitmap_fold(unsigned long *dst, const unsigned long *orig, - int sz, int bits); -extern int bitmap_find_free_region(unsigned long *bitmap, int bits, int order); -extern void bitmap_release_region(unsigned long *bitmap, int pos, int order); -extern int bitmap_allocate_region(unsigned long *bitmap, int pos, int order); -extern void bitmap_copy_le(void *dst, const unsigned long *src, int nbits); -extern int bitmap_ord_to_pos(const unsigned long *bitmap, int n, int bits); - -#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) % BITS_PER_LONG)) -#define BITMAP_LAST_WORD_MASK(nbits) \ -( \ - ((nbits) % BITS_PER_LONG) ? \ - (1UL<<((nbits) % BITS_PER_LONG))-1 : ~0UL \ -) - -#define small_const_nbits(nbits) \ - (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG) - -static inline void bitmap_zero(unsigned long *dst, int nbits) +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); + +#define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1))) +#define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1))) + +#define bitmap_size(nbits) (ALIGN(nbits, BITS_PER_LONG) / BITS_PER_BYTE) + +static __always_inline void bitmap_zero(unsigned long *dst, unsigned int nbits) { + unsigned int len = bitmap_size(nbits); + if (small_const_nbits(nbits)) - *dst = 0UL; - else { - int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); + *dst = 0; + else memset(dst, 0, len); - } } -static inline void bitmap_fill(unsigned long *dst, int nbits) +static __always_inline void bitmap_fill(unsigned long *dst, unsigned int nbits) { - size_t nlongs = BITS_TO_LONGS(nbits); - if (!small_const_nbits(nbits)) { - int len = (nlongs - 1) * sizeof(unsigned long); - memset(dst, 0xff, len); - } - dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits); + unsigned int len = bitmap_size(nbits); + + if (small_const_nbits(nbits)) + *dst = ~0UL; + else + memset(dst, 0xff, len); } -static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, - int nbits) +static __always_inline +void bitmap_copy(unsigned long *dst, const unsigned long *src, unsigned int nbits) { + unsigned int len = bitmap_size(nbits); + if (small_const_nbits(nbits)) *dst = *src; - else { - int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); + else memcpy(dst, src, len); - } } -static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, - const unsigned long *src2, int nbits) +/* + * Copy bitmap and clear tail bits in last word. + */ +static __always_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); +} + +static inline void bitmap_copy_and_extend(unsigned long *to, + const unsigned long *from, + unsigned int count, unsigned int size) +{ + unsigned int copy = BITS_TO_LONGS(count); + + memcpy(to, from, copy * sizeof(long)); + if (count % BITS_PER_LONG) + to[copy - 1] &= BITMAP_LAST_WORD_MASK(count); + memset(to + copy, 0, bitmap_size(size) - copy * sizeof(long)); +} + +/* + * 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 __always_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) != 0; + 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, int nbits) +static __always_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; @@ -204,8 +340,21 @@ static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, __bitmap_or(dst, src1, src2, nbits); } -static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, - const unsigned long *src2, int nbits) +static __always_inline +unsigned int bitmap_weighted_or(unsigned long *dst, const unsigned long *src1, + const unsigned long *src2, unsigned int nbits) +{ + if (small_const_nbits(nbits)) { + *dst = *src1 | *src2; + return hweight_long(*dst & BITMAP_LAST_WORD_MASK(nbits)); + } else { + return __bitmap_weighted_or(dst, src1, src2, nbits); + } +} + +static __always_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; @@ -213,34 +362,63 @@ static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, __bitmap_xor(dst, src1, src2, nbits); } -static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, - const unsigned long *src2, int nbits) +static __always_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)) != 0; + 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, - int nbits) +static __always_inline +void bitmap_complement(unsigned long *dst, const unsigned long *src, unsigned int nbits) { if (small_const_nbits(nbits)) - *dst = ~(*src) & BITMAP_LAST_WORD_MASK(nbits); + *dst = ~(*src); else __bitmap_complement(dst, src, nbits); } -static inline int bitmap_equal(const unsigned long *src1, - const unsigned long *src2, int 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 __always_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)); - else - return __bitmap_equal(src1, src2, 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); } -static inline int bitmap_intersects(const unsigned long *src1, - const unsigned long *src2, int 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 __always_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 __always_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; @@ -248,8 +426,8 @@ static inline int bitmap_intersects(const unsigned long *src1, return __bitmap_intersects(src1, src2, nbits); } -static inline int bitmap_subset(const unsigned long *src1, - const unsigned long *src2, int nbits) +static __always_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)); @@ -257,53 +435,417 @@ static inline int bitmap_subset(const unsigned long *src1, return __bitmap_subset(src1, src2, nbits); } -static inline int bitmap_empty(const unsigned long *src, int nbits) +static __always_inline +bool bitmap_empty(const unsigned long *src, unsigned nbits) { if (small_const_nbits(nbits)) return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); - else - return __bitmap_empty(src, nbits); + + return find_first_bit(src, nbits) == nbits; } -static inline int bitmap_full(const unsigned long *src, int nbits) +static __always_inline +bool bitmap_full(const unsigned long *src, unsigned int nbits) { if (small_const_nbits(nbits)) return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); - else - return __bitmap_full(src, nbits); + + return find_first_zero_bit(src, nbits) == nbits; } -static inline int bitmap_weight(const unsigned long *src, int 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 inline void bitmap_shift_right(unsigned long *dst, - const unsigned long *src, int n, int 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 +unsigned long bitmap_weight_andnot(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_andnot(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 __always_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 __always_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 >> n; + *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits); else - __bitmap_shift_right(dst, src, n, nbits); + __bitmap_shift_left(dst, src, shift, nbits); } -static inline void bitmap_shift_left(unsigned long *dst, - const unsigned long *src, int n, int nbits) +static __always_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 = (*src << n) & BITMAP_LAST_WORD_MASK(nbits); + *dst = (*old & ~(*mask)) | (*new & *mask); else - __bitmap_shift_left(dst, src, n, nbits); + __bitmap_replace(dst, old, new, mask, nbits); +} + +/** + * bitmap_scatter - Scatter a bitmap according to the given mask + * @dst: scattered bitmap + * @src: gathered bitmap + * @mask: mask representing bits to assign to in the scattered bitmap + * @nbits: number of bits in each of these bitmaps + * + * Scatters bitmap with sequential bits according to the given @mask. + * + * Example: + * If @src bitmap = 0x005a, with @mask = 0x1313, @dst will be 0x0302. + * + * Or in binary form + * @src @mask @dst + * 0000000001011010 0001001100010011 0000001100000010 + * + * (Bits 0, 1, 2, 3, 4, 5 are copied to the bits 0, 1, 4, 8, 9, 12) + * + * A more 'visual' description of the operation:: + * + * src: 0000000001011010 + * |||||| + * +------+||||| + * | +----+|||| + * | |+----+||| + * | || +-+|| + * | || | || + * mask: ...v..vv...v..vv + * ...0..11...0..10 + * dst: 0000001100000010 + * + * A relationship exists between bitmap_scatter() and bitmap_gather(). See + * bitmap_gather() for the bitmap gather detailed operations. TL;DR: + * bitmap_gather() can be seen as the 'reverse' bitmap_scatter() operation. + */ +static __always_inline +void bitmap_scatter(unsigned long *dst, const unsigned long *src, + const unsigned long *mask, unsigned int nbits) +{ + unsigned int n = 0; + unsigned int bit; + + bitmap_zero(dst, nbits); + + for_each_set_bit(bit, mask, nbits) + __assign_bit(bit, dst, test_bit(n++, src)); +} + +/** + * bitmap_gather - Gather a bitmap according to given mask + * @dst: gathered bitmap + * @src: scattered bitmap + * @mask: mask representing bits to extract from in the scattered bitmap + * @nbits: number of bits in each of these bitmaps + * + * Gathers bitmap with sparse bits according to the given @mask. + * + * Example: + * If @src bitmap = 0x0302, with @mask = 0x1313, @dst will be 0x001a. + * + * Or in binary form + * @src @mask @dst + * 0000001100000010 0001001100010011 0000000000011010 + * + * (Bits 0, 1, 4, 8, 9, 12 are copied to the bits 0, 1, 2, 3, 4, 5) + * + * A more 'visual' description of the operation:: + * + * mask: ...v..vv...v..vv + * src: 0000001100000010 + * ^ ^^ ^ 0 + * | || | 10 + * | || > 010 + * | |+--> 1010 + * | +--> 11010 + * +----> 011010 + * dst: 0000000000011010 + * + * A relationship exists between bitmap_gather() and bitmap_scatter(). See + * bitmap_scatter() for the bitmap scatter detailed operations. TL;DR: + * bitmap_scatter() can be seen as the 'reverse' bitmap_gather() operation. + * + * Suppose scattered computed using bitmap_scatter(scattered, src, mask, n). + * The operation bitmap_gather(result, scattered, mask, n) leads to a result + * equal or equivalent to src. + * + * The result can be 'equivalent' because bitmap_scatter() and bitmap_gather() + * are not bijective. + * The result and src values are equivalent in that sense that a call to + * bitmap_scatter(res, src, mask, n) and a call to + * bitmap_scatter(res, result, mask, n) will lead to the same res value. + */ +static __always_inline +void bitmap_gather(unsigned long *dst, const unsigned long *src, + const unsigned long *mask, unsigned int nbits) +{ + unsigned int n = 0; + unsigned int bit; + + bitmap_zero(dst, nbits); + + for_each_set_bit(bit, mask, nbits) + __assign_bit(n++, dst, test_bit(bit, src)); +} + +static __always_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_release_region - release allocated bitmap region + * @bitmap: array of unsigned longs corresponding to the bitmap + * @pos: beginning of bit region to release + * @order: region size (log base 2 of number of bits) to release + * + * This is the complement to __bitmap_find_free_region() and releases + * the found region (by clearing it in the bitmap). + */ +static __always_inline +void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order) +{ + bitmap_clear(bitmap, pos, BIT(order)); +} + +/** + * bitmap_allocate_region - allocate bitmap region + * @bitmap: array of unsigned longs corresponding to the bitmap + * @pos: beginning of bit region to allocate + * @order: region size (log base 2 of number of bits) to allocate + * + * Allocate (set bits in) a specified region of a bitmap. + * + * Returns: 0 on success, or %-EBUSY if specified region wasn't + * free (not all bits were zero). + */ +static __always_inline +int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order) +{ + unsigned int len = BIT(order); + + if (find_next_bit(bitmap, pos + len, pos) < pos + len) + return -EBUSY; + bitmap_set(bitmap, pos, len); + return 0; } -static inline int bitmap_parse(const char *buf, unsigned int buflen, - unsigned long *maskp, int nmaskbits) +/** + * bitmap_find_free_region - find a contiguous aligned mem region + * @bitmap: array of unsigned longs corresponding to the bitmap + * @bits: number of bits in the bitmap + * @order: region size (log base 2 of number of bits) to find + * + * Find a region of free (zero) bits in a @bitmap of @bits bits and + * allocate them (set them to one). Only consider regions of length + * a power (@order) of two, aligned to that power of two, which + * makes the search algorithm much faster. + * + * Returns: the bit offset in bitmap of the allocated region, + * or -errno on failure. + */ +static __always_inline +int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order) { - return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits); + unsigned int pos, end; /* scans bitmap by regions of size order */ + + for (pos = 0; (end = pos + BIT(order)) <= bits; pos = end) { + if (!bitmap_allocate_region(bitmap, pos, order)) + return pos; + } + return -ENOMEM; } +/** + * 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 __always_inline void bitmap_from_u64(unsigned long *dst, u64 mask) +{ + bitmap_from_arr64(dst, &mask, 64); +} + +/** + * bitmap_read - read a value of n-bits from the memory region + * @map: address to the bitmap memory region + * @start: bit offset of the n-bit value + * @nbits: size of value in bits, nonzero, up to BITS_PER_LONG + * + * Returns: value of @nbits bits located at the @start bit offset within the + * @map memory region. For @nbits = 0 and @nbits > BITS_PER_LONG the return + * value is undefined. + */ +static __always_inline +unsigned long bitmap_read(const unsigned long *map, unsigned long start, unsigned long nbits) +{ + size_t index = BIT_WORD(start); + unsigned long offset = start % BITS_PER_LONG; + unsigned long space = BITS_PER_LONG - offset; + unsigned long value_low, value_high; + + if (unlikely(!nbits || nbits > BITS_PER_LONG)) + return 0; + + if (space >= nbits) + return (map[index] >> offset) & BITMAP_LAST_WORD_MASK(nbits); + + value_low = map[index] & BITMAP_FIRST_WORD_MASK(start); + value_high = map[index + 1] & BITMAP_LAST_WORD_MASK(start + nbits); + return (value_low >> offset) | (value_high << space); +} + +/** + * bitmap_write - write n-bit value within a memory region + * @map: address to the bitmap memory region + * @value: value to write, clamped to nbits + * @start: bit offset of the n-bit value + * @nbits: size of value in bits, nonzero, up to BITS_PER_LONG. + * + * bitmap_write() behaves as-if implemented as @nbits calls of __assign_bit(), + * i.e. bits beyond @nbits are ignored: + * + * for (bit = 0; bit < nbits; bit++) + * __assign_bit(start + bit, bitmap, val & BIT(bit)); + * + * For @nbits == 0 and @nbits > BITS_PER_LONG no writes are performed. + */ +static __always_inline +void bitmap_write(unsigned long *map, unsigned long value, + unsigned long start, unsigned long nbits) +{ + size_t index; + unsigned long offset; + unsigned long space; + unsigned long mask; + bool fit; + + if (unlikely(!nbits || nbits > BITS_PER_LONG)) + return; + + mask = BITMAP_LAST_WORD_MASK(nbits); + value &= mask; + offset = start % BITS_PER_LONG; + space = BITS_PER_LONG - offset; + fit = space >= nbits; + index = BIT_WORD(start); + + map[index] &= (fit ? (~(mask << offset)) : ~BITMAP_FIRST_WORD_MASK(start)); + map[index] |= value << offset; + if (fit) + return; + + map[index + 1] &= BITMAP_FIRST_WORD_MASK(start + nbits); + map[index + 1] |= (value >> space); +} + +#define bitmap_get_value8(map, start) \ + bitmap_read(map, start, BITS_PER_BYTE) +#define bitmap_set_value8(map, value, start) \ + bitmap_write(map, value, start, BITS_PER_BYTE) + #endif /* __ASSEMBLY__ */ #endif /* __LINUX_BITMAP_H */ |