1 files changed, 462 insertions, 0 deletions

diff --git a/include/asm-i386/bitops.h b/include/asm-i386/bitops.h
new file mode 100644
index 000000000000..9db0b712d57a
--- /dev/null
+++ b/include/asm-i386/bitops.h
@@ -0,0 +1,462 @@
+#ifndef _I386_BITOPS_H
+#define _I386_BITOPS_H
+
+/*
+ * Copyright 1992, Linus Torvalds.
+ */
+
+#include <linux/config.h>
+#include <linux/compiler.h>
+
+/*
+ * These have to be done with inline assembly: that way the bit-setting
+ * is guaranteed to be atomic. All bit operations return 0 if the bit
+ * was cleared before the operation and != 0 if it was not.
+ *
+ * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
+ */
+
+#ifdef CONFIG_SMP
+#define LOCK_PREFIX "lock ; "
+#else
+#define LOCK_PREFIX ""
+#endif
+
+#define ADDR (*(volatile long *) addr)
+
+/**
+ * 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: there are no guarantees that this function will not be reordered
+ * on non x86 architectures, so if you are writting portable code,
+ * make sure not to rely on its reordering 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 unsigned long * addr)
+{
+        __asm__ __volatile__( LOCK_PREFIX
+                "btsl %1,%0"
+                :"=m" (ADDR)
+                :"Ir" (nr));
+}
+
+/**
+ * __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 unsigned long * addr)
+{
+        __asm__(
+                "btsl %1,%0"
+                :"=m" (ADDR)
+                :"Ir" (nr));
+}
+
+/**
+ * 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 unsigned long * addr)
+{
+        __asm__ __volatile__( LOCK_PREFIX
+                "btrl %1,%0"
+                :"=m" (ADDR)
+                :"Ir" (nr));
+}
+
+static inline void __clear_bit(int nr, volatile unsigned long * addr)
+{
+        __asm__ __volatile__(
+                "btrl %1,%0"
+                :"=m" (ADDR)
+                :"Ir" (nr));
+}
+#define smp_mb__before_clear_bit()      barrier()
+#define smp_mb__after_clear_bit()       barrier()
+
+/**
+ * __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(int nr, volatile unsigned long * addr)
+{
+        __asm__ __volatile__(
+                "btcl %1,%0"
+                :"=m" (ADDR)
+                :"Ir" (nr));
+}
+
+/**
+ * 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. It may be
+ * reordered on other architectures than x86.
+ * 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 unsigned long * addr)
+{
+        __asm__ __volatile__( LOCK_PREFIX
+                "btcl %1,%0"
+                :"=m" (ADDR)
+                :"Ir" (nr));
+}
+
+/**
+ * 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 may be reordered on other architectures than x86.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_set_bit(int nr, volatile unsigned long * addr)
+{
+        int oldbit;
+
+        __asm__ __volatile__( LOCK_PREFIX
+                "btsl %2,%1\n\tsbbl %0,%0"
+                :"=r" (oldbit),"=m" (ADDR)
+                :"Ir" (nr) : "memory");
+        return oldbit;
+}
+
+/**
+ * __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 unsigned long * addr)
+{
+        int oldbit;
+
+        __asm__(
+                "btsl %2,%1\n\tsbbl %0,%0"
+                :"=r" (oldbit),"=m" (ADDR)
+                :"Ir" (nr));
+        return oldbit;
+}
+
+/**
+ * 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 can be reorderdered on other architectures other than x86.
+ * It also implies a memory barrier.
+ */
+static inline int test_and_clear_bit(int nr, volatile unsigned long * addr)
+{
+        int oldbit;
+
+        __asm__ __volatile__( LOCK_PREFIX
+                "btrl %2,%1\n\tsbbl %0,%0"
+                :"=r" (oldbit),"=m" (ADDR)
+                :"Ir" (nr) : "memory");
+        return oldbit;
+}
+
+/**
+ * __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(int nr, volatile unsigned long *addr)
+{
+        int oldbit;
+
+        __asm__(
+                "btrl %2,%1\n\tsbbl %0,%0"
+                :"=r" (oldbit),"=m" (ADDR)
+                :"Ir" (nr));
+        return oldbit;
+}
+
+/* WARNING: non atomic and it can be reordered! */
+static inline int __test_and_change_bit(int nr, volatile unsigned long *addr)
+{
+        int oldbit;
+
+        __asm__ __volatile__(
+                "btcl %2,%1\n\tsbbl %0,%0"
+                :"=r" (oldbit),"=m" (ADDR)
+                :"Ir" (nr) : "memory");
+        return oldbit;
+}
+
+/**
+ * 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(int nr, volatile unsigned long* addr)
+{
+        int oldbit;
+
+        __asm__ __volatile__( LOCK_PREFIX
+                "btcl %2,%1\n\tsbbl %0,%0"
+                :"=r" (oldbit),"=m" (ADDR)
+                :"Ir" (nr) : "memory");
+        return oldbit;
+}
+
+#if 0 /* Fool kernel-doc since it doesn't do macros yet */
+/**
+ * test_bit - Determine whether a bit is set
+ * @nr: bit number to test
+ * @addr: Address to start counting from
+ */
+static int test_bit(int nr, const volatile void * addr);
+#endif
+
+static inline int constant_test_bit(int nr, const volatile unsigned long *addr)
+{
+        return ((1UL << (nr & 31)) & (addr[nr >> 5])) != 0;
+}
+
+static inline int variable_test_bit(int nr, const volatile unsigned long * addr)
+{
+        int oldbit;
+
+        __asm__ __volatile__(
+                "btl %2,%1\n\tsbbl %0,%0"
+                :"=r" (oldbit)
+                :"m" (ADDR),"Ir" (nr));
+        return oldbit;
+}
+
+#define test_bit(nr,addr) \
+(__builtin_constant_p(nr) ? \
+ constant_test_bit((nr),(addr)) : \
+ variable_test_bit((nr),(addr)))
+
+#undef ADDR
+
+/**
+ * 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(const unsigned long *addr, unsigned size)
+{
+        int d0, d1, d2;
+        int res;
+
+        if (!size)
+                return 0;
+        /* This looks at memory. Mark it volatile to tell gcc not to move it around */
+        __asm__ __volatile__(
+                "movl $-1,%%eax\n\t"
+                "xorl %%edx,%%edx\n\t"
+                "repe; scasl\n\t"
+                "je 1f\n\t"
+                "xorl -4(%%edi),%%eax\n\t"
+                "subl $4,%%edi\n\t"
+                "bsfl %%eax,%%edx\n"
+                "1:\tsubl %%ebx,%%edi\n\t"
+                "shll $3,%%edi\n\t"
+                "addl %%edi,%%edx"
+                :"=d" (res), "=&c" (d0), "=&D" (d1), "=&a" (d2)
+                :"1" ((size + 31) >> 5), "2" (addr), "b" (addr) : "memory");
+        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
+ */
+int find_next_zero_bit(const unsigned long *addr, int size, int 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, not the number of the byte
+ * containing a bit.
+ */
+static inline int find_first_bit(const unsigned long *addr, unsigned size)
+{
+        int d0, d1;
+        int res;
+
+        /* This looks at memory. Mark it volatile to tell gcc not to move it around */
+        __asm__ __volatile__(
+                "xorl %%eax,%%eax\n\t"
+                "repe; scasl\n\t"
+                "jz 1f\n\t"
+                "leal -4(%%edi),%%edi\n\t"
+                "bsfl (%%edi),%%eax\n"
+                "1:\tsubl %%ebx,%%edi\n\t"
+                "shll $3,%%edi\n\t"
+                "addl %%edi,%%eax"
+                :"=a" (res), "=&c" (d0), "=&D" (d1)
+                :"1" ((size + 31) >> 5), "2" (addr), "b" (addr) : "memory");
+        return res;
+}
+
+/**
+ * find_next_bit - find the first 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
+ */
+int find_next_bit(const unsigned long *addr, int size, int offset);
+
+/**
+ * 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)
+{
+        __asm__("bsfl %1,%0"
+                :"=r" (word)
+                :"r" (~word));
+        return word;
+}
+
+/**
+ * __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)
+{
+        __asm__("bsfl %1,%0"
+                :"=r" (word)
+                :"rm" (word));
+        return word;
+}
+
+/*
+ * fls: find last bit set.
+ */
+
+#define fls(x) generic_fls(x)
+
+#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)
+{
+        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;
+}
+
+/**
+ * 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).
+ */
+static inline int ffs(int x)
+{
+        int r;
+
+        __asm__("bsfl %1,%0\n\t"
+                "jnz 1f\n\t"
+                "movl $-1,%0\n"
+                "1:" : "=r" (r) : "rm" (x));
+        return r+1;
+}
+
+/**
+ * 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 __KERNEL__
+
+#define ext2_set_bit(nr,addr) \
+        __test_and_set_bit((nr),(unsigned long*)addr)
+#define ext2_set_bit_atomic(lock,nr,addr) \
+        test_and_set_bit((nr),(unsigned long*)addr)
+#define ext2_clear_bit(nr, addr) \
+        __test_and_clear_bit((nr),(unsigned long*)addr)
+#define ext2_clear_bit_atomic(lock,nr, addr) \
+                test_and_clear_bit((nr),(unsigned long*)addr)
+#define ext2_test_bit(nr, addr)      test_bit((nr),(unsigned long*)addr)
+#define ext2_find_first_zero_bit(addr, size) \
+        find_first_zero_bit((unsigned long*)addr, size)
+#define ext2_find_next_zero_bit(addr, size, off) \
+        find_next_zero_bit((unsigned long*)addr, size, off)
+
+/* Bitmap functions for the minix filesystem.  */
+#define minix_test_and_set_bit(nr,addr) __test_and_set_bit(nr,(void*)addr)
+#define minix_set_bit(nr,addr) __set_bit(nr,(void*)addr)
+#define minix_test_and_clear_bit(nr,addr) __test_and_clear_bit(nr,(void*)addr)
+#define minix_test_bit(nr,addr) test_bit(nr,(void*)addr)
+#define minix_find_first_zero_bit(addr,size) \
+        find_first_zero_bit((void*)addr,size)
+
+#endif /* __KERNEL__ */
+
+#endif /* _I386_BITOPS_H */