v4.19.13 snapshot.
diff --git a/include/linux/bitmap.h b/include/linux/bitmap.h
new file mode 100644
index 0000000..acf5e8d
--- /dev/null
+++ b/include/linux/bitmap.h
@@ -0,0 +1,477 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+#ifndef __LINUX_BITMAP_H
+#define __LINUX_BITMAP_H
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+#include <linux/bitops.h>
+#include <linux/string.h>
+#include <linux/kernel.h>
+
+/*
+ * 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:
+ *
+ * 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_find_next_zero_area_off(buf, len, pos, n, mask) as above
+ * 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_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_to_arr32(buf, src, nbits) Copy nbits from buf to u32[] dst
+ *
+ * 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.
+ */
+extern unsigned long *bitmap_alloc(unsigned int nbits, gfp_t flags);
+extern unsigned long *bitmap_zalloc(unsigned int nbits, gfp_t flags);
+extern void bitmap_free(const unsigned long *bitmap);
+
+/*
+ * lib/bitmap.c provides these functions:
+ */
+
+extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits);
+extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits);
+extern int __bitmap_equal(const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int nbits);
+extern void __bitmap_complement(unsigned long *dst, const unsigned long *src,
+ unsigned int nbits);
+extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src,
+ unsigned int shift, unsigned int nbits);
+extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src,
+ unsigned int shift, unsigned int nbits);
+extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int nbits);
+extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int nbits);
+extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int nbits);
+extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int nbits);
+extern int __bitmap_intersects(const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int nbits);
+extern int __bitmap_subset(const unsigned long *bitmap1,
+ const unsigned long *bitmap2, unsigned int nbits);
+extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits);
+extern void __bitmap_set(unsigned long *map, unsigned int start, int len);
+extern void __bitmap_clear(unsigned long *map, unsigned int start, int len);
+
+extern 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);
+}
+
+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_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, unsigned int nbits);
+extern 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, unsigned int bits);
+extern void bitmap_fold(unsigned long *dst, const unsigned long *orig,
+ unsigned int sz, unsigned int nbits);
+extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order);
+extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order);
+extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order);
+
+#ifdef __BIG_ENDIAN
+extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits);
+#else
+#define bitmap_copy_le bitmap_copy
+#endif
+extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits);
+extern int bitmap_print_to_pagebuf(bool list, char *buf,
+ const unsigned long *maskp, int nmaskbits);
+
+#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 small_const_nbits(nbits) \
+ (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG)
+
+static inline void bitmap_zero(unsigned long *dst, unsigned int nbits)
+{
+ if (small_const_nbits(nbits))
+ *dst = 0UL;
+ else {
+ unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
+ memset(dst, 0, len);
+ }
+}
+
+static inline void bitmap_fill(unsigned long *dst, unsigned int nbits)
+{
+ if (small_const_nbits(nbits))
+ *dst = ~0UL;
+ else {
+ unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
+ memset(dst, 0xff, len);
+ }
+}
+
+static inline void bitmap_copy(unsigned long *dst, const unsigned long *src,
+ unsigned int nbits)
+{
+ if (small_const_nbits(nbits))
+ *dst = *src;
+ else {
+ unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long);
+ 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, and
+ * therefore conversion is not needed when copying data from/to arrays of u32.
+ */
+#if BITS_PER_LONG == 64
+extern void bitmap_from_arr32(unsigned long *bitmap, const u32 *buf,
+ unsigned int nbits);
+extern 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
+
+static inline int 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 int 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 int 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);
+}
+
+static inline int 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 int 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 int 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 int 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 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 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 (__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 (__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, 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 int bitmap_parse(const char *buf, unsigned int buflen,
+ unsigned long *maskp, int nmaskbits)
+{
+ return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits);
+}
+
+/**
+ * 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)
+{
+ dst[0] = mask & ULONG_MAX;
+
+ if (sizeof(mask) > sizeof(unsigned long))
+ dst[1] = mask >> 32;
+}
+
+#endif /* __ASSEMBLY__ */
+
+#endif /* __LINUX_BITMAP_H */