summaryrefslogtreecommitdiffstats
path: root/arch/mips/include/asm/bitops.h
diff options
context:
space:
mode:
Diffstat (limited to 'arch/mips/include/asm/bitops.h')
-rw-r--r--arch/mips/include/asm/bitops.h902
1 files changed, 902 insertions, 0 deletions
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h
new file mode 100644
index 0000000..f2dc533
--- /dev/null
+++ b/arch/mips/include/asm/bitops.h
@@ -0,0 +1,902 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License. See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * Copyright (c) 1994 - 1997, 1999, 2000 Ralf Baechle (ralf@gnu.org)
+ * Copyright (c) 2000 Silicon Graphics, Inc.
+ */
+#ifndef _ASM_BITOPS_H
+#define _ASM_BITOPS_H
+
+#include <linux/types.h>
+#include <asm/byteorder.h> /* sigh ... */
+
+#ifdef __KERNEL__
+
+#include <asm/sgidefs.h>
+#include <asm/system.h>
+#include <linux/config.h>
+
+/*
+ * clear_bit() doesn't provide any barrier for the compiler.
+ */
+#define smp_mb__before_clear_bit() barrier()
+#define smp_mb__after_clear_bit() barrier()
+
+/*
+ * Only disable interrupt for kernel mode stuff to keep usermode stuff
+ * that dares to use kernel include files alive.
+ */
+#define __bi_flags unsigned long flags
+#define __bi_cli() __cli()
+#define __bi_save_flags(x) __save_flags(x)
+#define __bi_save_and_cli(x) __save_and_cli(x)
+#define __bi_restore_flags(x) __restore_flags(x)
+#else
+#define __bi_flags
+#define __bi_cli()
+#define __bi_save_flags(x)
+#define __bi_save_and_cli(x)
+#define __bi_restore_flags(x)
+#endif /* __KERNEL__ */
+
+#ifdef CONFIG_CPU_HAS_LLSC
+
+#include <asm/mipsregs.h>
+
+/*
+ * These functions for MIPS ISA > 1 are interrupt and SMP proof and
+ * interrupt friendly
+ */
+
+/*
+ * set_bit - Atomically set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This function is atomic and may not be reordered. See __set_bit()
+ * if you do not require the atomic guarantees.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static __inline__ void
+set_bit(int nr, volatile void *addr)
+{
+ unsigned long *m = ((unsigned long *) addr) + (nr >> 5);
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ "1:\tll\t%0, %1\t\t# set_bit\n\t"
+ "or\t%0, %2\n\t"
+ "sc\t%0, %1\n\t"
+ "beqz\t%0, 1b"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (1UL << (nr & 0x1f)), "m" (*m));
+}
+
+/*
+ * __set_bit - Set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * Unlike set_bit(), this function is non-atomic and may be reordered.
+ * If it's called on the same region of memory simultaneously, the effect
+ * may be that only one operation succeeds.
+ */
+static __inline__ void __set_bit(int nr, volatile void * addr)
+{
+ unsigned long * m = ((unsigned long *) addr) + (nr >> 5);
+
+ *m |= 1UL << (nr & 31);
+}
+#define PLATFORM__SET_BIT
+
+/*
+ * clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * clear_bit() is atomic and may not be reordered. However, it does
+ * not contain a memory barrier, so if it is used for locking purposes,
+ * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
+ * in order to ensure changes are visible on other processors.
+ */
+static __inline__ void
+clear_bit(int nr, volatile void *addr)
+{
+ unsigned long *m = ((unsigned long *) addr) + (nr >> 5);
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ "1:\tll\t%0, %1\t\t# clear_bit\n\t"
+ "and\t%0, %2\n\t"
+ "sc\t%0, %1\n\t"
+ "beqz\t%0, 1b\n\t"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (~(1UL << (nr & 0x1f))), "m" (*m));
+}
+
+/*
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * change_bit() is atomic and may not be reordered.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static __inline__ void
+change_bit(int nr, volatile void *addr)
+{
+ unsigned long *m = ((unsigned long *) addr) + (nr >> 5);
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ "1:\tll\t%0, %1\t\t# change_bit\n\t"
+ "xor\t%0, %2\n\t"
+ "sc\t%0, %1\n\t"
+ "beqz\t%0, 1b"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (1UL << (nr & 0x1f)), "m" (*m));
+}
+
+/*
+ * __change_bit - Toggle a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * Unlike change_bit(), this function is non-atomic and may be reordered.
+ * If it's called on the same region of memory simultaneously, the effect
+ * may be that only one operation succeeds.
+ */
+static __inline__ void __change_bit(int nr, volatile void * addr)
+{
+ unsigned long * m = ((unsigned long *) addr) + (nr >> 5);
+
+ *m ^= 1UL << (nr & 31);
+}
+
+/*
+ * test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int
+test_and_set_bit(int nr, volatile void *addr)
+{
+ unsigned long *m = ((unsigned long *) addr) + (nr >> 5);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ ".set\tnoreorder\t\t# test_and_set_bit\n"
+ "1:\tll\t%0, %1\n\t"
+ "or\t%2, %0, %3\n\t"
+ "sc\t%2, %1\n\t"
+ "beqz\t%2, 1b\n\t"
+ " and\t%2, %0, %3\n\t"
+ ".set\treorder"
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & 0x1f)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+}
+
+/*
+ * __test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ * If two examples of this operation race, one can appear to succeed
+ * but actually fail. You must protect multiple accesses with a lock.
+ */
+static __inline__ int __test_and_set_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *a) != 0;
+ *a |= mask;
+
+ return retval;
+}
+
+/*
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int
+test_and_clear_bit(int nr, volatile void *addr)
+{
+ unsigned long *m = ((unsigned long *) addr) + (nr >> 5);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ ".set\tnoreorder\t\t# test_and_clear_bit\n"
+ "1:\tll\t%0, %1\n\t"
+ "or\t%2, %0, %3\n\t"
+ "xor\t%2, %3\n\t"
+ "sc\t%2, %1\n\t"
+ "beqz\t%2, 1b\n\t"
+ " and\t%2, %0, %3\n\t"
+ ".set\treorder"
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & 0x1f)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+}
+
+/*
+ * __test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ * If two examples of this operation race, one can appear to succeed
+ * but actually fail. You must protect multiple accesses with a lock.
+ */
+static __inline__ int __test_and_clear_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *a) != 0;
+ *a &= ~mask;
+
+ return retval;
+}
+
+/*
+ * test_and_change_bit - Change a bit and return its new value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int
+test_and_change_bit(int nr, volatile void *addr)
+{
+ unsigned long *m = ((unsigned long *) addr) + (nr >> 5);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ ".set\tnoreorder\t\t# test_and_change_bit\n"
+ "1:\tll\t%0, %1\n\t"
+ "xor\t%2, %0, %3\n\t"
+ "sc\t%2, %1\n\t"
+ "beqz\t%2, 1b\n\t"
+ " and\t%2, %0, %3\n\t"
+ ".set\treorder"
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & 0x1f)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+}
+
+/*
+ * __test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ * If two examples of this operation race, one can appear to succeed
+ * but actually fail. You must protect multiple accesses with a lock.
+ */
+static __inline__ int __test_and_change_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *a) != 0;
+ *a ^= mask;
+
+ return retval;
+}
+
+#else /* MIPS I */
+
+/*
+ * set_bit - Atomically set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * This function is atomic and may not be reordered. See __set_bit()
+ * if you do not require the atomic guarantees.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static __inline__ void set_bit(int nr, volatile void * addr)
+{
+ int mask;
+ volatile int *a = addr;
+ __bi_flags;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ __bi_save_and_cli(flags);
+ *a |= mask;
+ __bi_restore_flags(flags);
+}
+
+/*
+ * __set_bit - Set a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * Unlike set_bit(), this function is non-atomic and may be reordered.
+ * If it's called on the same region of memory simultaneously, the effect
+ * may be that only one operation succeeds.
+ */
+static __inline__ void __set_bit(int nr, volatile void * addr)
+{
+ int mask;
+ volatile int *a = addr;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ *a |= mask;
+}
+
+/*
+ * clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * clear_bit() is atomic and may not be reordered. However, it does
+ * not contain a memory barrier, so if it is used for locking purposes,
+ * you should call smp_mb__before_clear_bit() and/or smp_mb__after_clear_bit()
+ * in order to ensure changes are visible on other processors.
+ */
+static __inline__ void clear_bit(int nr, volatile void * addr)
+{
+ int mask;
+ volatile int *a = addr;
+ __bi_flags;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ __bi_save_and_cli(flags);
+ *a &= ~mask;
+ __bi_restore_flags(flags);
+}
+
+/*
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * change_bit() is atomic and may not be reordered.
+ * Note that @nr may be almost arbitrarily large; this function is not
+ * restricted to acting on a single-word quantity.
+ */
+static __inline__ void change_bit(int nr, volatile void * addr)
+{
+ int mask;
+ volatile int *a = addr;
+ __bi_flags;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ __bi_save_and_cli(flags);
+ *a ^= mask;
+ __bi_restore_flags(flags);
+}
+
+/*
+ * __change_bit - Toggle a bit in memory
+ * @nr: the bit to set
+ * @addr: the address to start counting from
+ *
+ * Unlike change_bit(), this function is non-atomic and may be reordered.
+ * If it's called on the same region of memory simultaneously, the effect
+ * may be that only one operation succeeds.
+ */
+static __inline__ void __change_bit(int nr, volatile void * addr)
+{
+ unsigned long * m = ((unsigned long *) addr) + (nr >> 5);
+
+ *m ^= 1UL << (nr & 31);
+}
+
+/*
+ * test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int test_and_set_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+ __bi_flags;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ __bi_save_and_cli(flags);
+ retval = (mask & *a) != 0;
+ *a |= mask;
+ __bi_restore_flags(flags);
+
+ return retval;
+}
+
+/*
+ * __test_and_set_bit - Set a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ * If two examples of this operation race, one can appear to succeed
+ * but actually fail. You must protect multiple accesses with a lock.
+ */
+static __inline__ int __test_and_set_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *a) != 0;
+ *a |= mask;
+
+ return retval;
+}
+
+/*
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int test_and_clear_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+ __bi_flags;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ __bi_save_and_cli(flags);
+ retval = (mask & *a) != 0;
+ *a &= ~mask;
+ __bi_restore_flags(flags);
+
+ return retval;
+}
+
+/*
+ * __test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ * If two examples of this operation race, one can appear to succeed
+ * but actually fail. You must protect multiple accesses with a lock.
+ */
+static __inline__ int __test_and_clear_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *a) != 0;
+ *a &= ~mask;
+
+ return retval;
+}
+
+/*
+ * test_and_change_bit - Change a bit and return its new value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is atomic and cannot be reordered.
+ * It also implies a memory barrier.
+ */
+static __inline__ int test_and_change_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+ __bi_flags;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ __bi_save_and_cli(flags);
+ retval = (mask & *a) != 0;
+ *a ^= mask;
+ __bi_restore_flags(flags);
+
+ return retval;
+}
+
+/*
+ * __test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to set
+ * @addr: Address to count from
+ *
+ * This operation is non-atomic and can be reordered.
+ * If two examples of this operation race, one can appear to succeed
+ * but actually fail. You must protect multiple accesses with a lock.
+ */
+static __inline__ int __test_and_change_bit(int nr, volatile void * addr)
+{
+ int mask, retval;
+ volatile int *a = addr;
+
+ a += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *a) != 0;
+ *a ^= mask;
+
+ return retval;
+}
+
+#undef __bi_flags
+#undef __bi_cli
+#undef __bi_save_flags
+#undef __bi_restore_flags
+
+#endif /* MIPS I */
+
+/*
+ * 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 volatile void *addr)
+{
+ return ((1UL << (nr & 31)) & (((const unsigned int *) addr)[nr >> 5])) != 0;
+}
+
+#ifndef __MIPSEB__
+
+/* Little endian versions. */
+
+/*
+ * find_first_zero_bit - find the first zero 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 zero bit, not the number of the byte
+ * containing a bit.
+ */
+static __inline__ int find_first_zero_bit (void *addr, unsigned size)
+{
+ unsigned long dummy;
+ int res;
+
+ if (!size)
+ return 0;
+
+ __asm__ (".set\tnoreorder\n\t"
+ ".set\tnoat\n"
+ "1:\tsubu\t$1,%6,%0\n\t"
+ "blez\t$1,2f\n\t"
+ "lw\t$1,(%5)\n\t"
+ "addiu\t%5,4\n\t"
+#if (_MIPS_ISA == _MIPS_ISA_MIPS2 ) || (_MIPS_ISA == _MIPS_ISA_MIPS3 ) || \
+ (_MIPS_ISA == _MIPS_ISA_MIPS4 ) || (_MIPS_ISA == _MIPS_ISA_MIPS5 ) || \
+ (_MIPS_ISA == _MIPS_ISA_MIPS32) || (_MIPS_ISA == _MIPS_ISA_MIPS64)
+ "beql\t%1,$1,1b\n\t"
+ "addiu\t%0,32\n\t"
+#else
+ "addiu\t%0,32\n\t"
+ "beq\t%1,$1,1b\n\t"
+ "nop\n\t"
+ "subu\t%0,32\n\t"
+#endif
+#ifdef __MIPSEB__
+#error "Fix this for big endian"
+#endif /* __MIPSEB__ */
+ "li\t%1,1\n"
+ "1:\tand\t%2,$1,%1\n\t"
+ "beqz\t%2,2f\n\t"
+ "sll\t%1,%1,1\n\t"
+ "bnez\t%1,1b\n\t"
+ "add\t%0,%0,1\n\t"
+ ".set\tat\n\t"
+ ".set\treorder\n"
+ "2:"
+ : "=r" (res), "=r" (dummy), "=r" (addr)
+ : "0" ((signed int) 0), "1" ((unsigned int) 0xffffffff),
+ "2" (addr), "r" (size)
+ : "$1");
+
+ return res;
+}
+
+/*
+ * find_next_zero_bit - find the first zero bit in a memory region
+ * @addr: The address to base the search on
+ * @offset: The bitnumber to start searching at
+ * @size: The maximum size to search
+ */
+static __inline__ int find_next_zero_bit (void * addr, int size, int offset)
+{
+ unsigned int *p = ((unsigned int *) addr) + (offset >> 5);
+ int set = 0, bit = offset & 31, res;
+ unsigned long dummy;
+
+ if (bit) {
+ /*
+ * Look for zero in first byte
+ */
+#ifdef __MIPSEB__
+#error "Fix this for big endian byte order"
+#endif
+ __asm__(".set\tnoreorder\n\t"
+ ".set\tnoat\n"
+ "1:\tand\t$1,%4,%1\n\t"
+ "beqz\t$1,1f\n\t"
+ "sll\t%1,%1,1\n\t"
+ "bnez\t%1,1b\n\t"
+ "addiu\t%0,1\n\t"
+ ".set\tat\n\t"
+ ".set\treorder\n"
+ "1:"
+ : "=r" (set), "=r" (dummy)
+ : "0" (0), "1" (1 << bit), "r" (*p)
+ : "$1");
+ if (set < (32 - bit))
+ return set + offset;
+ set = 32 - bit;
+ p++;
+ }
+ /*
+ * No zero yet, search remaining full bytes for a zero
+ */
+ res = find_first_zero_bit(p, size - 32 * (p - (unsigned int *) addr));
+ return offset + set + res;
+}
+
+#endif /* !(__MIPSEB__) */
+
+/*
+ * ffz - find first zero in word.
+ * @word: The word to search
+ *
+ * Undefined if no zero exists, so code should check against ~0UL first.
+ */
+static __inline__ unsigned long ffz(unsigned long word)
+{
+ unsigned int __res;
+ unsigned int mask = 1;
+
+ __asm__ (
+ ".set\tnoreorder\n\t"
+ ".set\tnoat\n\t"
+ "move\t%0,$0\n"
+ "1:\tand\t$1,%2,%1\n\t"
+ "beqz\t$1,2f\n\t"
+ "sll\t%1,1\n\t"
+ "bnez\t%1,1b\n\t"
+ "addiu\t%0,1\n\t"
+ ".set\tat\n\t"
+ ".set\treorder\n"
+ "2:\n\t"
+ : "=&r" (__res), "=r" (mask)
+ : "r" (word), "1" (mask)
+ : "$1");
+
+ return __res;
+}
+
+#ifdef __KERNEL__
+
+/*
+ * hweightN - returns the hamming weight of a N-bit word
+ * @x: the word to weigh
+ *
+ * The Hamming Weight of a number is the total number of bits set in it.
+ */
+
+#define hweight32(x) generic_hweight32(x)
+#define hweight16(x) generic_hweight16(x)
+#define hweight8(x) generic_hweight8(x)
+
+#endif /* __KERNEL__ */
+
+#ifdef __MIPSEB__
+/*
+ * find_next_zero_bit - find the first zero bit in a memory region
+ * @addr: The address to base the search on
+ * @offset: The bitnumber to start searching at
+ * @size: The maximum size to search
+ */
+static __inline__ int find_next_zero_bit(void *addr, int size, int offset)
+{
+ unsigned long *p = ((unsigned long *) addr) + (offset >> 5);
+ unsigned long result = offset & ~31UL;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= 31UL;
+ if (offset) {
+ tmp = *(p++);
+ tmp |= ~0UL >> (32-offset);
+ if (size < 32)
+ goto found_first;
+ if (~tmp)
+ goto found_middle;
+ size -= 32;
+ result += 32;
+ }
+ while (size & ~31UL) {
+ if (~(tmp = *(p++)))
+ goto found_middle;
+ result += 32;
+ size -= 32;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+
+found_first:
+ tmp |= ~0UL << size;
+found_middle:
+ return result + ffz(tmp);
+}
+
+/* Linus sez that gcc can optimize the following correctly, we'll see if this
+ * holds on the Sparc as it does for the ALPHA.
+ */
+
+#if 0 /* Fool kernel-doc since it doesn't do macros yet */
+/*
+ * find_first_zero_bit - find the first zero 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 zero bit, not the number of the byte
+ * containing a bit.
+ */
+static int find_first_zero_bit (void *addr, unsigned size);
+#endif
+
+#define find_first_zero_bit(addr, size) \
+ find_next_zero_bit((addr), (size), 0)
+
+#endif /* (__MIPSEB__) */
+
+/* Now for the ext2 filesystem bit operations and helper routines. */
+
+#ifdef __MIPSEB__
+static __inline__ int ext2_set_bit(int nr, void * addr)
+{
+ int mask, retval, flags;
+ unsigned char *ADDR = (unsigned char *) addr;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+ save_and_cli(flags);
+ retval = (mask & *ADDR) != 0;
+ *ADDR |= mask;
+ restore_flags(flags);
+ return retval;
+}
+
+static __inline__ int ext2_clear_bit(int nr, void * addr)
+{
+ int mask, retval, flags;
+ unsigned char *ADDR = (unsigned char *) addr;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+ save_and_cli(flags);
+ retval = (mask & *ADDR) != 0;
+ *ADDR &= ~mask;
+ restore_flags(flags);
+ return retval;
+}
+
+static __inline__ int ext2_test_bit(int nr, const void * addr)
+{
+ int mask;
+ const unsigned char *ADDR = (const unsigned char *) addr;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+ return ((mask & *ADDR) != 0);
+}
+
+#define ext2_find_first_zero_bit(addr, size) \
+ ext2_find_next_zero_bit((addr), (size), 0)
+
+static __inline__ unsigned long ext2_find_next_zero_bit(void *addr, unsigned long size, unsigned long offset)
+{
+ unsigned long *p = ((unsigned long *) addr) + (offset >> 5);
+ unsigned long result = offset & ~31UL;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= 31UL;
+ if(offset) {
+ /* We hold the little endian value in tmp, but then the
+ * shift is illegal. So we could keep a big endian value
+ * in tmp, like this:
+ *
+ * tmp = __swab32(*(p++));
+ * tmp |= ~0UL >> (32-offset);
+ *
+ * but this would decrease preformance, so we change the
+ * shift:
+ */
+ tmp = *(p++);
+ tmp |= __swab32(~0UL >> (32-offset));
+ if(size < 32)
+ goto found_first;
+ if(~tmp)
+ goto found_middle;
+ size -= 32;
+ result += 32;
+ }
+ while(size & ~31UL) {
+ if(~(tmp = *(p++)))
+ goto found_middle;
+ result += 32;
+ size -= 32;
+ }
+ if(!size)
+ return result;
+ tmp = *p;
+
+found_first:
+ /* tmp is little endian, so we would have to swab the shift,
+ * see above. But then we have to swab tmp below for ffz, so
+ * we might as well do this here.
+ */
+ return result + ffz(__swab32(tmp) | (~0UL << size));
+found_middle:
+ return result + ffz(__swab32(tmp));
+}
+#else /* !(__MIPSEB__) */
+
+/* Native ext2 byte ordering, just collapse using defines. */
+#define ext2_set_bit(nr, addr) test_and_set_bit((nr), (addr))
+#define ext2_clear_bit(nr, addr) test_and_clear_bit((nr), (addr))
+#define ext2_test_bit(nr, addr) test_bit((nr), (addr))
+#define ext2_find_first_zero_bit(addr, size) find_first_zero_bit((addr), (size))
+#define ext2_find_next_zero_bit(addr, size, offset) \
+ find_next_zero_bit((addr), (size), (offset))
+
+#endif /* !(__MIPSEB__) */
+
+/*
+ * Bitmap functions for the minix filesystem.
+ * FIXME: These assume that Minix uses the native byte/bitorder.
+ * This limits the Minix filesystem's value for data exchange very much.
+ */
+#define minix_test_and_set_bit(nr,addr) test_and_set_bit(nr,addr)
+#define minix_set_bit(nr,addr) set_bit(nr,addr)
+#define minix_test_and_clear_bit(nr,addr) test_and_clear_bit(nr,addr)
+#define minix_test_bit(nr,addr) test_bit(nr,addr)
+#define minix_find_first_zero_bit(addr,size) find_first_zero_bit(addr,size)
+
+#endif /* _ASM_BITOPS_H */
OpenPOWER on IntegriCloud