--- /dev/null
+#ifndef _I386_BITOPS_H
+#define _I386_BITOPS_H
+
+/*
+ * Copyright 1992, Linus Torvalds.
+ */
+
+
+/*
+ * 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 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)
+{
+ __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 void * 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 void * addr)
+{
+ __asm__ __volatile__( LOCK_PREFIX
+ "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 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)
+{
+ __asm__ __volatile__(
+ "btcl %1,%0"
+ :"=m" (ADDR)
+ :"Ir" (nr));
+}
+
+/**
+ * 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)
+{
+ __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 also implies a memory barrier.
+ */
+static __inline__ int test_and_set_bit(int nr, volatile void * 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 void * 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 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 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 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 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 void * 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 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 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 void * addr)
+{
+ return ((1UL << (nr & 31)) & (((const volatile unsigned int *) addr)[nr >> 5])) != 0;
+}
+
+static __inline__ int variable_test_bit(int nr, volatile void * 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)))
+
+/**
+ * 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)
+{
+ 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));
+ 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 long * p = ((unsigned long *) addr) + (offset >> 5);
+ int set = 0, bit = offset & 31, res;
+
+ if (bit) {
+ /*
+ * Look for zero in first byte
+ */
+ __asm__("bsfl %1,%0\n\t"
+ "jne 1f\n\t"
+ "movl $32, %0\n"
+ "1:"
+ : "=r" (set)
+ : "r" (~(*p >> bit)));
+ 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 long *) addr));
+ return (offset + set + res);
+}
+
+/**
+ * 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;
+}
+
+#ifdef __KERNEL__
+
+/**
+ * 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) : "g" (x));
+ return r+1;
+}
+#define PLATFORM_FFS
+
+static inline int __ilog2(unsigned int x)
+{
+ return generic_fls(x) - 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 __test_and_set_bit
+#define ext2_clear_bit __test_and_clear_bit
+#define ext2_test_bit test_bit
+#define ext2_find_first_zero_bit find_first_zero_bit
+#define ext2_find_next_zero_bit find_next_zero_bit
+
+/* Bitmap functions for the minix filesystem. */
+#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 /* _I386_BITOPS_H */
Code Review / kvmfornfv.git / blobdiff