From 0d60175bd684cf6a14f750579d82dbd1ba97fcbc Mon Sep 17 00:00:00 2001 From: Anand Avati Date: Wed, 6 Mar 2013 01:11:59 -0800 Subject: contrib/qemu: Import qemu block source code This qemu block format source code and its minimal dependency files will be used in the next patch to implement a qemu-block format translator. Change-Id: Ic87638972f7ea9b3df84d7a0539512a250c11c1c BUG: 986775 Signed-off-by: Anand Avati Reviewed-on: http://review.gluster.org/5366 Tested-by: Gluster Build System Reviewed-by: Brian Foster --- contrib/qemu/include/qemu/bitops.h | 276 +++++++++++++++++++++++++++++++++++++ 1 file changed, 276 insertions(+) create mode 100644 contrib/qemu/include/qemu/bitops.h (limited to 'contrib/qemu/include/qemu/bitops.h') diff --git a/contrib/qemu/include/qemu/bitops.h b/contrib/qemu/include/qemu/bitops.h new file mode 100644 index 000000000..affcc969d --- /dev/null +++ b/contrib/qemu/include/qemu/bitops.h @@ -0,0 +1,276 @@ +/* + * Bitops Module + * + * Copyright (C) 2010 Corentin Chary + * + * Mostly inspired by (stolen from) linux/bitmap.h and linux/bitops.h + * + * This work is licensed under the terms of the GNU LGPL, version 2.1 or later. + * See the COPYING.LIB file in the top-level directory. + */ + +#ifndef BITOPS_H +#define BITOPS_H + +#include "qemu-common.h" +#include "host-utils.h" + +#define BITS_PER_BYTE CHAR_BIT +#define BITS_PER_LONG (sizeof (unsigned long) * BITS_PER_BYTE) + +#define BIT(nr) (1UL << (nr)) +#define BIT_MASK(nr) (1UL << ((nr) % BITS_PER_LONG)) +#define BIT_WORD(nr) ((nr) / BITS_PER_LONG) +#define BITS_TO_LONGS(nr) DIV_ROUND_UP(nr, BITS_PER_BYTE * sizeof(long)) + +/** + * set_bit - Set a bit in memory + * @nr: the bit to set + * @addr: the address to start counting from + */ +static inline void set_bit(int nr, unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = addr + BIT_WORD(nr); + + *p |= mask; +} + +/** + * clear_bit - Clears a bit in memory + * @nr: Bit to clear + * @addr: Address to start counting from + */ +static inline void clear_bit(int nr, unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = addr + BIT_WORD(nr); + + *p &= ~mask; +} + +/** + * change_bit - Toggle a bit in memory + * @nr: Bit to change + * @addr: Address to start counting from + */ +static inline void change_bit(int nr, unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = addr + BIT_WORD(nr); + + *p ^= mask; +} + +/** + * test_and_set_bit - Set a bit and return its old value + * @nr: Bit to set + * @addr: Address to count from + */ +static inline int test_and_set_bit(int nr, unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = addr + BIT_WORD(nr); + unsigned long old = *p; + + *p = old | mask; + return (old & mask) != 0; +} + +/** + * test_and_clear_bit - Clear a bit and return its old value + * @nr: Bit to clear + * @addr: Address to count from + */ +static inline int test_and_clear_bit(int nr, unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = addr + BIT_WORD(nr); + unsigned long old = *p; + + *p = old & ~mask; + return (old & mask) != 0; +} + +/** + * test_and_change_bit - Change a bit and return its old value + * @nr: Bit to change + * @addr: Address to count from + */ +static inline int test_and_change_bit(int nr, unsigned long *addr) +{ + unsigned long mask = BIT_MASK(nr); + unsigned long *p = addr + BIT_WORD(nr); + unsigned long old = *p; + + *p = old ^ mask; + return (old & mask) != 0; +} + +/** + * test_bit - Determine whether a bit is set + * @nr: bit number to test + * @addr: Address to start counting from + */ +static inline int test_bit(int nr, const unsigned long *addr) +{ + return 1UL & (addr[BIT_WORD(nr)] >> (nr & (BITS_PER_LONG-1))); +} + +/** + * find_last_bit - find the last set bit in a memory region + * @addr: The address to start the search at + * @size: The maximum size to search + * + * Returns the bit number of the first set bit, or size. + */ +unsigned long find_last_bit(const unsigned long *addr, + unsigned long size); + +/** + * find_next_bit - find the next set bit in a memory region + * @addr: The address to base the search on + * @offset: The bitnumber to start searching at + * @size: The bitmap size in bits + */ +unsigned long find_next_bit(const unsigned long *addr, + unsigned long size, unsigned long offset); + +/** + * find_next_zero_bit - find the next cleared bit in a memory region + * @addr: The address to base the search on + * @offset: The bitnumber to start searching at + * @size: The bitmap size in bits + */ + +unsigned long find_next_zero_bit(const unsigned long *addr, + unsigned long size, + unsigned long offset); + +/** + * find_first_bit - find the first set bit in a memory region + * @addr: The address to start the search at + * @size: The maximum size to search + * + * Returns the bit number of the first set bit. + */ +static inline unsigned long find_first_bit(const unsigned long *addr, + unsigned long size) +{ + return find_next_bit(addr, size, 0); +} + +/** + * find_first_zero_bit - find the first cleared bit in a memory region + * @addr: The address to start the search at + * @size: The maximum size to search + * + * Returns the bit number of the first cleared bit. + */ +static inline unsigned long find_first_zero_bit(const unsigned long *addr, + unsigned long size) +{ + return find_next_zero_bit(addr, size, 0); +} + +static inline unsigned long hweight_long(unsigned long w) +{ + unsigned long count; + + for (count = 0; w; w >>= 1) { + count += w & 1; + } + return count; +} + +/** + * extract32: + * @value: the value to extract the bit field from + * @start: the lowest bit in the bit field (numbered from 0) + * @length: the length of the bit field + * + * Extract from the 32 bit input @value the bit field specified by the + * @start and @length parameters, and return it. The bit field must + * lie entirely within the 32 bit word. It is valid to request that + * all 32 bits are returned (ie @length 32 and @start 0). + * + * Returns: the value of the bit field extracted from the input value. + */ +static inline uint32_t extract32(uint32_t value, int start, int length) +{ + assert(start >= 0 && length > 0 && length <= 32 - start); + return (value >> start) & (~0U >> (32 - length)); +} + +/** + * extract64: + * @value: the value to extract the bit field from + * @start: the lowest bit in the bit field (numbered from 0) + * @length: the length of the bit field + * + * Extract from the 64 bit input @value the bit field specified by the + * @start and @length parameters, and return it. The bit field must + * lie entirely within the 64 bit word. It is valid to request that + * all 64 bits are returned (ie @length 64 and @start 0). + * + * Returns: the value of the bit field extracted from the input value. + */ +static inline uint64_t extract64(uint64_t value, int start, int length) +{ + assert(start >= 0 && length > 0 && length <= 64 - start); + return (value >> start) & (~0ULL >> (64 - length)); +} + +/** + * deposit32: + * @value: initial value to insert bit field into + * @start: the lowest bit in the bit field (numbered from 0) + * @length: the length of the bit field + * @fieldval: the value to insert into the bit field + * + * Deposit @fieldval into the 32 bit @value at the bit field specified + * by the @start and @length parameters, and return the modified + * @value. Bits of @value outside the bit field are not modified. + * Bits of @fieldval above the least significant @length bits are + * ignored. The bit field must lie entirely within the 32 bit word. + * It is valid to request that all 32 bits are modified (ie @length + * 32 and @start 0). + * + * Returns: the modified @value. + */ +static inline uint32_t deposit32(uint32_t value, int start, int length, + uint32_t fieldval) +{ + uint32_t mask; + assert(start >= 0 && length > 0 && length <= 32 - start); + mask = (~0U >> (32 - length)) << start; + return (value & ~mask) | ((fieldval << start) & mask); +} + +/** + * deposit64: + * @value: initial value to insert bit field into + * @start: the lowest bit in the bit field (numbered from 0) + * @length: the length of the bit field + * @fieldval: the value to insert into the bit field + * + * Deposit @fieldval into the 64 bit @value at the bit field specified + * by the @start and @length parameters, and return the modified + * @value. Bits of @value outside the bit field are not modified. + * Bits of @fieldval above the least significant @length bits are + * ignored. The bit field must lie entirely within the 64 bit word. + * It is valid to request that all 64 bits are modified (ie @length + * 64 and @start 0). + * + * Returns: the modified @value. + */ +static inline uint64_t deposit64(uint64_t value, int start, int length, + uint64_t fieldval) +{ + uint64_t mask; + assert(start >= 0 && length > 0 && length <= 64 - start); + mask = (~0ULL >> (64 - length)) << start; + return (value & ~mask) | ((fieldval << start) & mask); +} + +#endif -- cgit