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authorLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
committerLinus Torvalds <torvalds@ppc970.osdl.org>2005-04-16 15:20:36 -0700
commit1da177e4c3f41524e886b7f1b8a0c1fc7321cac2 (patch)
tree0bba044c4ce775e45a88a51686b5d9f90697ea9d /include/asm-mips/bitops.h
Linux-2.6.12-rc2v2.6.12-rc2
Initial git repository build. I'm not bothering with the full history, even though we have it. We can create a separate "historical" git archive of that later if we want to, and in the meantime it's about 3.2GB when imported into git - space that would just make the early git days unnecessarily complicated, when we don't have a lot of good infrastructure for it. Let it rip!
Diffstat (limited to 'include/asm-mips/bitops.h')
-rw-r--r--include/asm-mips/bitops.h850
1 files changed, 850 insertions, 0 deletions
diff --git a/include/asm-mips/bitops.h b/include/asm-mips/bitops.h
new file mode 100644
index 00000000000..779d2187a6a
--- /dev/null
+++ b/include/asm-mips/bitops.h
@@ -0,0 +1,850 @@
+/*
+ * 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) 1999, 2000 Silicon Graphics, Inc.
+ */
+#ifndef _ASM_BITOPS_H
+#define _ASM_BITOPS_H
+
+#include <linux/config.h>
+#include <linux/compiler.h>
+#include <linux/types.h>
+#include <asm/byteorder.h> /* sigh ... */
+#include <asm/cpu-features.h>
+
+#if (_MIPS_SZLONG == 32)
+#define SZLONG_LOG 5
+#define SZLONG_MASK 31UL
+#define __LL "ll "
+#define __SC "sc "
+#define cpu_to_lelongp(x) cpu_to_le32p((__u32 *) (x))
+#elif (_MIPS_SZLONG == 64)
+#define SZLONG_LOG 6
+#define SZLONG_MASK 63UL
+#define __LL "lld "
+#define __SC "scd "
+#define cpu_to_lelongp(x) cpu_to_le64p((__u64 *) (x))
+#endif
+
+#ifdef __KERNEL__
+
+#include <asm/interrupt.h>
+#include <asm/sgidefs.h>
+#include <asm/war.h>
+
+/*
+ * clear_bit() doesn't provide any barrier for the compiler.
+ */
+#define smp_mb__before_clear_bit() smp_mb()
+#define smp_mb__after_clear_bit() smp_mb()
+
+/*
+ * 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_local_irq_save(x) local_irq_save(x)
+#define __bi_local_irq_restore(x) local_irq_restore(x)
+#else
+#define __bi_flags
+#define __bi_local_irq_save(x)
+#define __bi_local_irq_restore(x)
+#endif /* __KERNEL__ */
+
+/*
+ * 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(unsigned long nr, volatile unsigned long *addr)
+{
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp;
+
+ if (cpu_has_llsc && R10000_LLSC_WAR) {
+ __asm__ __volatile__(
+ "1: " __LL "%0, %1 # set_bit \n"
+ " or %0, %2 \n"
+ " "__SC "%0, %1 \n"
+ " beqzl %0, 1b \n"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
+ } else if (cpu_has_llsc) {
+ __asm__ __volatile__(
+ "1: " __LL "%0, %1 # set_bit \n"
+ " or %0, %2 \n"
+ " "__SC "%0, %1 \n"
+ " beqz %0, 1b \n"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
+ } else {
+ volatile unsigned long *a = addr;
+ unsigned long mask;
+ __bi_flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << (nr & SZLONG_MASK);
+ __bi_local_irq_save(flags);
+ *a |= mask;
+ __bi_local_irq_restore(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(unsigned long nr, volatile unsigned long * addr)
+{
+ unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+
+ *m |= 1UL << (nr & SZLONG_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(unsigned long nr, volatile unsigned long *addr)
+{
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp;
+
+ if (cpu_has_llsc && R10000_LLSC_WAR) {
+ __asm__ __volatile__(
+ "1: " __LL "%0, %1 # clear_bit \n"
+ " and %0, %2 \n"
+ " " __SC "%0, %1 \n"
+ " beqzl %0, 1b \n"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (~(1UL << (nr & SZLONG_MASK))), "m" (*m));
+ } else if (cpu_has_llsc) {
+ __asm__ __volatile__(
+ "1: " __LL "%0, %1 # clear_bit \n"
+ " and %0, %2 \n"
+ " " __SC "%0, %1 \n"
+ " beqz %0, 1b \n"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (~(1UL << (nr & SZLONG_MASK))), "m" (*m));
+ } else {
+ volatile unsigned long *a = addr;
+ unsigned long mask;
+ __bi_flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << (nr & SZLONG_MASK);
+ __bi_local_irq_save(flags);
+ *a &= ~mask;
+ __bi_local_irq_restore(flags);
+ }
+}
+
+/*
+ * __clear_bit - Clears a bit in memory
+ * @nr: Bit to clear
+ * @addr: Address to start counting from
+ *
+ * Unlike clear_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 __clear_bit(unsigned long nr, volatile unsigned long * addr)
+{
+ unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+
+ *m &= ~(1UL << (nr & SZLONG_MASK));
+}
+
+/*
+ * change_bit - Toggle a bit in memory
+ * @nr: Bit to change
+ * @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(unsigned long nr, volatile unsigned long *addr)
+{
+ if (cpu_has_llsc && R10000_LLSC_WAR) {
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ "1: " __LL "%0, %1 # change_bit \n"
+ " xor %0, %2 \n"
+ " "__SC "%0, %1 \n"
+ " beqzl %0, 1b \n"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
+ } else if (cpu_has_llsc) {
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp;
+
+ __asm__ __volatile__(
+ "1: " __LL "%0, %1 # change_bit \n"
+ " xor %0, %2 \n"
+ " "__SC "%0, %1 \n"
+ " beqz %0, 1b \n"
+ : "=&r" (temp), "=m" (*m)
+ : "ir" (1UL << (nr & SZLONG_MASK)), "m" (*m));
+ } else {
+ volatile unsigned long *a = addr;
+ unsigned long mask;
+ __bi_flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << (nr & SZLONG_MASK);
+ __bi_local_irq_save(flags);
+ *a ^= mask;
+ __bi_local_irq_restore(flags);
+ }
+}
+
+/*
+ * __change_bit - Toggle a bit in memory
+ * @nr: the bit to change
+ * @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(unsigned long nr, volatile unsigned long * addr)
+{
+ unsigned long * m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+
+ *m ^= 1UL << (nr & SZLONG_MASK);
+}
+
+/*
+ * 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(unsigned long nr,
+ volatile unsigned long *addr)
+{
+ if (cpu_has_llsc && R10000_LLSC_WAR) {
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ "1: " __LL "%0, %1 # test_and_set_bit \n"
+ " or %2, %0, %3 \n"
+ " " __SC "%2, %1 \n"
+ " beqzl %2, 1b \n"
+ " and %2, %0, %3 \n"
+#ifdef CONFIG_SMP
+ "sync \n"
+#endif
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+ } else if (cpu_has_llsc) {
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ " .set noreorder # test_and_set_bit \n"
+ "1: " __LL "%0, %1 \n"
+ " or %2, %0, %3 \n"
+ " " __SC "%2, %1 \n"
+ " beqz %2, 1b \n"
+ " and %2, %0, %3 \n"
+#ifdef CONFIG_SMP
+ "sync \n"
+#endif
+ ".set\treorder"
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+ } else {
+ volatile unsigned long *a = addr;
+ unsigned long mask;
+ int retval;
+ __bi_flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << (nr & SZLONG_MASK);
+ __bi_local_irq_save(flags);
+ retval = (mask & *a) != 0;
+ *a |= mask;
+ __bi_local_irq_restore(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(unsigned long nr,
+ volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned long mask;
+ int retval;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << (nr & SZLONG_MASK);
+ retval = (mask & *a) != 0;
+ *a |= mask;
+
+ return retval;
+}
+
+/*
+ * test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @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(unsigned long nr,
+ volatile unsigned long *addr)
+{
+ if (cpu_has_llsc && R10000_LLSC_WAR) {
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ "1: " __LL "%0, %1 # test_and_clear_bit \n"
+ " or %2, %0, %3 \n"
+ " xor %2, %3 \n"
+ __SC "%2, %1 \n"
+ " beqzl %2, 1b \n"
+ " and %2, %0, %3 \n"
+#ifdef CONFIG_SMP
+ " sync \n"
+#endif
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+ } else if (cpu_has_llsc) {
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ " .set noreorder # test_and_clear_bit \n"
+ "1: " __LL "%0, %1 \n"
+ " or %2, %0, %3 \n"
+ " xor %2, %3 \n"
+ __SC "%2, %1 \n"
+ " beqz %2, 1b \n"
+ " and %2, %0, %3 \n"
+#ifdef CONFIG_SMP
+ " sync \n"
+#endif
+ " .set reorder \n"
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+ } else {
+ volatile unsigned long *a = addr;
+ unsigned long mask;
+ int retval;
+ __bi_flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << (nr & SZLONG_MASK);
+ __bi_local_irq_save(flags);
+ retval = (mask & *a) != 0;
+ *a &= ~mask;
+ __bi_local_irq_restore(flags);
+
+ return retval;
+ }
+}
+
+/*
+ * __test_and_clear_bit - Clear a bit and return its old value
+ * @nr: Bit to clear
+ * @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(unsigned long nr,
+ volatile unsigned long * addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned long mask;
+ int retval;
+
+ a += (nr >> SZLONG_LOG);
+ mask = 1UL << (nr & SZLONG_MASK);
+ retval = ((mask & *a) != 0);
+ *a &= ~mask;
+
+ return retval;
+}
+
+/*
+ * test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @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(unsigned long nr,
+ volatile unsigned long *addr)
+{
+ if (cpu_has_llsc && R10000_LLSC_WAR) {
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ "1: " __LL " %0, %1 # test_and_change_bit \n"
+ " xor %2, %0, %3 \n"
+ " "__SC "%2, %1 \n"
+ " beqzl %2, 1b \n"
+ " and %2, %0, %3 \n"
+#ifdef CONFIG_SMP
+ " sync \n"
+#endif
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+ } else if (cpu_has_llsc) {
+ unsigned long *m = ((unsigned long *) addr) + (nr >> SZLONG_LOG);
+ unsigned long temp, res;
+
+ __asm__ __volatile__(
+ " .set noreorder # test_and_change_bit \n"
+ "1: " __LL " %0, %1 \n"
+ " xor %2, %0, %3 \n"
+ " "__SC "\t%2, %1 \n"
+ " beqz %2, 1b \n"
+ " and %2, %0, %3 \n"
+#ifdef CONFIG_SMP
+ " sync \n"
+#endif
+ " .set reorder \n"
+ : "=&r" (temp), "=m" (*m), "=&r" (res)
+ : "r" (1UL << (nr & SZLONG_MASK)), "m" (*m)
+ : "memory");
+
+ return res != 0;
+ } else {
+ volatile unsigned long *a = addr;
+ unsigned long mask, retval;
+ __bi_flags;
+
+ a += nr >> SZLONG_LOG;
+ mask = 1UL << (nr & SZLONG_MASK);
+ __bi_local_irq_save(flags);
+ retval = (mask & *a) != 0;
+ *a ^= mask;
+ __bi_local_irq_restore(flags);
+
+ return retval;
+ }
+}
+
+/*
+ * __test_and_change_bit - Change a bit and return its old value
+ * @nr: Bit to change
+ * @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(unsigned long nr,
+ volatile unsigned long *addr)
+{
+ volatile unsigned long *a = addr;
+ unsigned long mask;
+ int retval;
+
+ a += (nr >> SZLONG_LOG);
+ mask = 1UL << (nr & SZLONG_MASK);
+ retval = ((mask & *a) != 0);
+ *a ^= mask;
+
+ return retval;
+}
+
+#undef __bi_flags
+#undef __bi_local_irq_save
+#undef __bi_local_irq_restore
+
+/*
+ * test_bit - Determine whether a bit is set
+ * @nr: bit number to test
+ * @addr: Address to start counting from
+ */
+static inline int test_bit(unsigned long nr, const volatile unsigned long *addr)
+{
+ return 1UL & (addr[nr >> SZLONG_LOG] >> (nr & SZLONG_MASK));
+}
+
+/*
+ * 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)
+{
+ int b = 0, s;
+
+ word = ~word;
+#ifdef CONFIG_MIPS32
+ s = 16; if (word << 16 != 0) s = 0; b += s; word >>= s;
+ s = 8; if (word << 24 != 0) s = 0; b += s; word >>= s;
+ s = 4; if (word << 28 != 0) s = 0; b += s; word >>= s;
+ s = 2; if (word << 30 != 0) s = 0; b += s; word >>= s;
+ s = 1; if (word << 31 != 0) s = 0; b += s;
+#endif
+#ifdef CONFIG_MIPS64
+ s = 32; if (word << 32 != 0) s = 0; b += s; word >>= s;
+ s = 16; if (word << 48 != 0) s = 0; b += s; word >>= s;
+ s = 8; if (word << 56 != 0) s = 0; b += s; word >>= s;
+ s = 4; if (word << 60 != 0) s = 0; b += s; word >>= s;
+ s = 2; if (word << 62 != 0) s = 0; b += s; word >>= s;
+ s = 1; if (word << 63 != 0) s = 0; b += s;
+#endif
+
+ return b;
+}
+
+/*
+ * __ffs - find first bit in word.
+ * @word: The word to search
+ *
+ * Undefined if no bit exists, so code should check against 0 first.
+ */
+static inline unsigned long __ffs(unsigned long word)
+{
+ return ffz(~word);
+}
+
+/*
+ * fls: find last bit set.
+ */
+
+#define fls(x) generic_fls(x)
+
+/*
+ * 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 unsigned long find_next_zero_bit(const unsigned long *addr,
+ unsigned long size, unsigned long offset)
+{
+ const unsigned long *p = addr + (offset >> SZLONG_LOG);
+ unsigned long result = offset & ~SZLONG_MASK;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= SZLONG_MASK;
+ if (offset) {
+ tmp = *(p++);
+ tmp |= ~0UL >> (_MIPS_SZLONG-offset);
+ if (size < _MIPS_SZLONG)
+ goto found_first;
+ if (~tmp)
+ goto found_middle;
+ size -= _MIPS_SZLONG;
+ result += _MIPS_SZLONG;
+ }
+ while (size & ~SZLONG_MASK) {
+ if (~(tmp = *(p++)))
+ goto found_middle;
+ result += _MIPS_SZLONG;
+ size -= _MIPS_SZLONG;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+
+found_first:
+ tmp |= ~0UL << size;
+ if (tmp == ~0UL) /* Are any bits zero? */
+ return result + size; /* Nope. */
+found_middle:
+ return result + ffz(tmp);
+}
+
+#define find_first_zero_bit(addr, size) \
+ find_next_zero_bit((addr), (size), 0)
+
+/*
+ * 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 maximum size to search
+ */
+static inline unsigned long find_next_bit(const unsigned long *addr,
+ unsigned long size, unsigned long offset)
+{
+ const unsigned long *p = addr + (offset >> SZLONG_LOG);
+ unsigned long result = offset & ~SZLONG_MASK;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= SZLONG_MASK;
+ if (offset) {
+ tmp = *(p++);
+ tmp &= ~0UL << offset;
+ if (size < _MIPS_SZLONG)
+ goto found_first;
+ if (tmp)
+ goto found_middle;
+ size -= _MIPS_SZLONG;
+ result += _MIPS_SZLONG;
+ }
+ while (size & ~SZLONG_MASK) {
+ if ((tmp = *(p++)))
+ goto found_middle;
+ result += _MIPS_SZLONG;
+ size -= _MIPS_SZLONG;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+
+found_first:
+ tmp &= ~0UL >> (_MIPS_SZLONG - size);
+ if (tmp == 0UL) /* Are any bits set? */
+ return result + size; /* Nope. */
+found_middle:
+ return result + __ffs(tmp);
+}
+
+/*
+ * 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, not the number of the byte
+ * containing a bit.
+ */
+#define find_first_bit(addr, size) \
+ find_next_bit((addr), (size), 0)
+
+#ifdef __KERNEL__
+
+/*
+ * Every architecture must define this function. It's the fastest
+ * way of searching a 140-bit bitmap where the first 100 bits are
+ * unlikely to be set. It's guaranteed that at least one of the 140
+ * bits is cleared.
+ */
+static inline int sched_find_first_bit(const unsigned long *b)
+{
+#ifdef CONFIG_MIPS32
+ if (unlikely(b[0]))
+ return __ffs(b[0]);
+ if (unlikely(b[1]))
+ return __ffs(b[1]) + 32;
+ if (unlikely(b[2]))
+ return __ffs(b[2]) + 64;
+ if (b[3])
+ return __ffs(b[3]) + 96;
+ return __ffs(b[4]) + 128;
+#endif
+#ifdef CONFIG_MIPS64
+ if (unlikely(b[0]))
+ return __ffs(b[0]);
+ if (unlikely(b[1]))
+ return __ffs(b[1]) + 64;
+ return __ffs(b[2]) + 128;
+#endif
+}
+
+/*
+ * ffs - find first bit set
+ * @x: the word to search
+ *
+ * This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+
+#define ffs(x) generic_ffs(x)
+
+/*
+ * 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 hweight64(x) generic_hweight64(x)
+#define hweight32(x) generic_hweight32(x)
+#define hweight16(x) generic_hweight16(x)
+#define hweight8(x) generic_hweight8(x)
+
+static inline int __test_and_set_le_bit(unsigned long nr, unsigned long *addr)
+{
+ unsigned char *ADDR = (unsigned char *) addr;
+ int mask, retval;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+ retval = (mask & *ADDR) != 0;
+ *ADDR |= mask;
+
+ return retval;
+}
+
+static inline int __test_and_clear_le_bit(unsigned long nr, unsigned long *addr)
+{
+ unsigned char *ADDR = (unsigned char *) addr;
+ int mask, retval;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+ retval = (mask & *ADDR) != 0;
+ *ADDR &= ~mask;
+
+ return retval;
+}
+
+static inline int test_le_bit(unsigned long nr, const unsigned long * addr)
+{
+ const unsigned char *ADDR = (const unsigned char *) addr;
+ int mask;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+
+ return ((mask & *ADDR) != 0);
+}
+
+static inline unsigned long find_next_zero_le_bit(unsigned long *addr,
+ unsigned long size, unsigned long offset)
+{
+ unsigned long *p = ((unsigned long *) addr) + (offset >> SZLONG_LOG);
+ unsigned long result = offset & ~SZLONG_MASK;
+ unsigned long tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= SZLONG_MASK;
+ if (offset) {
+ tmp = cpu_to_lelongp(p++);
+ tmp |= ~0UL >> (_MIPS_SZLONG-offset); /* bug or feature ? */
+ if (size < _MIPS_SZLONG)
+ goto found_first;
+ if (~tmp)
+ goto found_middle;
+ size -= _MIPS_SZLONG;
+ result += _MIPS_SZLONG;
+ }
+ while (size & ~SZLONG_MASK) {
+ if (~(tmp = cpu_to_lelongp(p++)))
+ goto found_middle;
+ result += _MIPS_SZLONG;
+ size -= _MIPS_SZLONG;
+ }
+ if (!size)
+ return result;
+ tmp = cpu_to_lelongp(p);
+
+found_first:
+ tmp |= ~0UL << size;
+ if (tmp == ~0UL) /* Are any bits zero? */
+ return result + size; /* Nope. */
+
+found_middle:
+ return result + ffz(tmp);
+}
+
+#define find_first_zero_le_bit(addr, size) \
+ find_next_zero_le_bit((addr), (size), 0)
+
+#define ext2_set_bit(nr,addr) \
+ __test_and_set_le_bit((nr),(unsigned long*)addr)
+#define ext2_clear_bit(nr, addr) \
+ __test_and_clear_le_bit((nr),(unsigned long*)addr)
+ #define ext2_set_bit_atomic(lock, nr, addr) \
+({ \
+ int ret; \
+ spin_lock(lock); \
+ ret = ext2_set_bit((nr), (addr)); \
+ spin_unlock(lock); \
+ ret; \
+})
+
+#define ext2_clear_bit_atomic(lock, nr, addr) \
+({ \
+ int ret; \
+ spin_lock(lock); \
+ ret = ext2_clear_bit((nr), (addr)); \
+ spin_unlock(lock); \
+ ret; \
+})
+#define ext2_test_bit(nr, addr) test_le_bit((nr),(unsigned long*)addr)
+#define ext2_find_first_zero_bit(addr, size) \
+ find_first_zero_le_bit((unsigned long*)addr, size)
+#define ext2_find_next_zero_bit(addr, size, off) \
+ find_next_zero_le_bit((unsigned long*)addr, size, off)
+
+/*
+ * 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 /* __KERNEL__ */
+
+#endif /* _ASM_BITOPS_H */