--- /dev/null
+/*
+ * bitops.h: Bit string operations on the ppc
+ */
+
+#ifndef _PPC_BITOPS_H
+#define _PPC_BITOPS_H
+
+#include <asm/byteorder.h>
+
+extern void set_bit(int nr, volatile void *addr);
+extern void clear_bit(int nr, volatile void *addr);
+extern void change_bit(int nr, volatile void *addr);
+extern int test_and_set_bit(int nr, volatile void *addr);
+extern int test_and_clear_bit(int nr, volatile void *addr);
+extern int test_and_change_bit(int nr, volatile void *addr);
+
+/*
+ * Arguably these bit operations don't imply any memory barrier or
+ * SMP ordering, but in fact a lot of drivers expect them to imply
+ * both, since they do on x86 cpus.
+ */
+#ifdef CONFIG_SMP
+#define SMP_WMB "eieio\n"
+#define SMP_MB "\nsync"
+#else
+#define SMP_WMB
+#define SMP_MB
+#endif /* CONFIG_SMP */
+
+#define __INLINE_BITOPS 1
+
+#if __INLINE_BITOPS
+/*
+ * These used to be if'd out here because using : "cc" as a constraint
+ * resulted in errors from egcs. Things may be OK with gcc-2.95.
+ */
+extern __inline__ void set_bit(int nr, volatile void * addr)
+{
+ unsigned long old;
+ unsigned long mask = 1 << (nr & 0x1f);
+ unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
+
+ __asm__ __volatile__(SMP_WMB "\
+1: lwarx %0,0,%3\n\
+ or %0,%0,%2\n\
+ stwcx. %0,0,%3\n\
+ bne 1b"
+ SMP_MB
+ : "=&r" (old), "=m" (*p)
+ : "r" (mask), "r" (p), "m" (*p)
+ : "cc" );
+}
+
+extern __inline__ void clear_bit(int nr, volatile void *addr)
+{
+ unsigned long old;
+ unsigned long mask = 1 << (nr & 0x1f);
+ unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
+
+ __asm__ __volatile__(SMP_WMB "\
+1: lwarx %0,0,%3\n\
+ andc %0,%0,%2\n\
+ stwcx. %0,0,%3\n\
+ bne 1b"
+ SMP_MB
+ : "=&r" (old), "=m" (*p)
+ : "r" (mask), "r" (p), "m" (*p)
+ : "cc");
+}
+
+extern __inline__ void change_bit(int nr, volatile void *addr)
+{
+ unsigned long old;
+ unsigned long mask = 1 << (nr & 0x1f);
+ unsigned long *p = ((unsigned long *)addr) + (nr >> 5);
+
+ __asm__ __volatile__(SMP_WMB "\
+1: lwarx %0,0,%3\n\
+ xor %0,%0,%2\n\
+ stwcx. %0,0,%3\n\
+ bne 1b"
+ SMP_MB
+ : "=&r" (old), "=m" (*p)
+ : "r" (mask), "r" (p), "m" (*p)
+ : "cc");
+}
+
+extern __inline__ int test_and_set_bit(int nr, volatile void *addr)
+{
+ unsigned int old, t;
+ unsigned int mask = 1 << (nr & 0x1f);
+ volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
+
+ __asm__ __volatile__(SMP_WMB "\
+1: lwarx %0,0,%4\n\
+ or %1,%0,%3\n\
+ stwcx. %1,0,%4\n\
+ bne 1b"
+ SMP_MB
+ : "=&r" (old), "=&r" (t), "=m" (*p)
+ : "r" (mask), "r" (p), "m" (*p)
+ : "cc");
+
+ return (old & mask) != 0;
+}
+
+extern __inline__ int test_and_clear_bit(int nr, volatile void *addr)
+{
+ unsigned int old, t;
+ unsigned int mask = 1 << (nr & 0x1f);
+ volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
+
+ __asm__ __volatile__(SMP_WMB "\
+1: lwarx %0,0,%4\n\
+ andc %1,%0,%3\n\
+ stwcx. %1,0,%4\n\
+ bne 1b"
+ SMP_MB
+ : "=&r" (old), "=&r" (t), "=m" (*p)
+ : "r" (mask), "r" (p), "m" (*p)
+ : "cc");
+
+ return (old & mask) != 0;
+}
+
+extern __inline__ int test_and_change_bit(int nr, volatile void *addr)
+{
+ unsigned int old, t;
+ unsigned int mask = 1 << (nr & 0x1f);
+ volatile unsigned int *p = ((volatile unsigned int *)addr) + (nr >> 5);
+
+ __asm__ __volatile__(SMP_WMB "\
+1: lwarx %0,0,%4\n\
+ xor %1,%0,%3\n\
+ stwcx. %1,0,%4\n\
+ bne 1b"
+ SMP_MB
+ : "=&r" (old), "=&r" (t), "=m" (*p)
+ : "r" (mask), "r" (p), "m" (*p)
+ : "cc");
+
+ return (old & mask) != 0;
+}
+#endif /* __INLINE_BITOPS */
+
+extern __inline__ int test_bit(int nr, __const__ volatile void *addr)
+{
+ __const__ unsigned int *p = (__const__ unsigned int *) addr;
+
+ return ((p[nr >> 5] >> (nr & 0x1f)) & 1) != 0;
+}
+
+/* Return the bit position of the most significant 1 bit in a word */
+/* - the result is undefined when x == 0 */
+extern __inline__ int __ilog2(unsigned int x)
+{
+ int lz;
+
+ asm ("cntlzw %0,%1" : "=r" (lz) : "r" (x));
+ return 31 - lz;
+}
+
+extern __inline__ int ffz(unsigned int x)
+{
+ if ((x = ~x) == 0)
+ return 32;
+ return __ilog2(x & -x);
+}
+
+/*
+ * fls: find last (most-significant) bit set.
+ * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
+ *
+ * On powerpc, __ilog2(0) returns -1, but this is not safe in general
+ */
+static __inline__ int fls(unsigned int x)
+{
+ return __ilog2(x) + 1;
+}
+#define PLATFORM_FLS
+
+/**
+ * fls64 - find last set bit in a 64-bit word
+ * @x: the word to search
+ *
+ * This is defined in a similar way as the libc and compiler builtin
+ * ffsll, but returns the position of the most significant set bit.
+ *
+ * fls64(value) returns 0 if value is 0 or the position of the last
+ * set bit if value is nonzero. The last (most significant) bit is
+ * at position 64.
+ */
+#if BITS_PER_LONG == 32
+static inline int fls64(__u64 x)
+{
+ __u32 h = x >> 32;
+ if (h)
+ return fls(h) + 32;
+ return fls(x);
+}
+#elif BITS_PER_LONG == 64
+static inline int fls64(__u64 x)
+{
+ if (x == 0)
+ return 0;
+ return __ilog2(x) + 1;
+}
+#else
+#error BITS_PER_LONG not 32 or 64
+#endif
+
+static inline int __ilog2_u64(u64 n)
+{
+ return fls64(n) - 1;
+}
+
+static inline int ffs64(u64 x)
+{
+ return __ilog2_u64(x & -x) + 1ull;
+}
+
+#ifdef __KERNEL__
+
+/*
+ * ffs: find first bit set. This is defined the same way as
+ * the libc and compiler builtin ffs routines, therefore
+ * differs in spirit from the above ffz (man ffs).
+ */
+extern __inline__ int ffs(int x)
+{
+ return __ilog2(x & -x) + 1;
+}
+#define PLATFORM_FFS
+
+/*
+ * hweightN: returns the hamming weight (i.e. the number
+ * of bits set) of a N-bit word
+ */
+
+#define hweight32(x) generic_hweight32(x)
+#define hweight16(x) generic_hweight16(x)
+#define hweight8(x) generic_hweight8(x)
+
+#endif /* __KERNEL__ */
+
+/*
+ * This implementation of find_{first,next}_zero_bit was stolen from
+ * Linus' asm-alpha/bitops.h.
+ */
+#define find_first_zero_bit(addr, size) \
+ find_next_zero_bit((addr), (size), 0)
+
+extern __inline__ unsigned long find_next_zero_bit(void * addr,
+ unsigned long size, unsigned long offset)
+{
+ unsigned int * p = ((unsigned int *) addr) + (offset >> 5);
+ unsigned int result = offset & ~31UL;
+ unsigned int 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 != ~0U)
+ goto found_middle;
+ size -= 32;
+ result += 32;
+ }
+ while (size >= 32) {
+ if ((tmp = *p++) != ~0U)
+ goto found_middle;
+ result += 32;
+ size -= 32;
+ }
+ if (!size)
+ return result;
+ tmp = *p;
+found_first:
+ tmp |= ~0UL << size;
+found_middle:
+ return result + ffz(tmp);
+}
+
+
+#define _EXT2_HAVE_ASM_BITOPS_
+
+#ifdef __KERNEL__
+/*
+ * test_and_{set,clear}_bit guarantee atomicity without
+ * disabling interrupts.
+ */
+#define ext2_set_bit(nr, addr) test_and_set_bit((nr) ^ 0x18, addr)
+#define ext2_clear_bit(nr, addr) test_and_clear_bit((nr) ^ 0x18, addr)
+
+#else
+extern __inline__ int ext2_set_bit(int nr, void * addr)
+{
+ int mask;
+ unsigned char *ADDR = (unsigned char *) addr;
+ int oldbit;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+ oldbit = (*ADDR & mask) ? 1 : 0;
+ *ADDR |= mask;
+ return oldbit;
+}
+
+extern __inline__ int ext2_clear_bit(int nr, void * addr)
+{
+ int mask;
+ unsigned char *ADDR = (unsigned char *) addr;
+ int oldbit;
+
+ ADDR += nr >> 3;
+ mask = 1 << (nr & 0x07);
+ oldbit = (*ADDR & mask) ? 1 : 0;
+ *ADDR = *ADDR & ~mask;
+ return oldbit;
+}
+#endif /* __KERNEL__ */
+
+extern __inline__ int ext2_test_bit(int nr, __const__ void * addr)
+{
+ __const__ unsigned char *ADDR = (__const__ unsigned char *) addr;
+
+ return (ADDR[nr >> 3] >> (nr & 7)) & 1;
+}
+
+/*
+ * This implementation of ext2_find_{first,next}_zero_bit was stolen from
+ * Linus' asm-alpha/bitops.h and modified for a big-endian machine.
+ */
+
+#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 int *p = ((unsigned int *) addr) + (offset >> 5);
+ unsigned int result = offset & ~31UL;
+ unsigned int tmp;
+
+ if (offset >= size)
+ return size;
+ size -= result;
+ offset &= 31UL;
+ if (offset) {
+ tmp = cpu_to_le32p(p++);
+ tmp |= ~0UL >> (32-offset);
+ if (size < 32)
+ goto found_first;
+ if (tmp != ~0U)
+ goto found_middle;
+ size -= 32;
+ result += 32;
+ }
+ while (size >= 32) {
+ if ((tmp = cpu_to_le32p(p++)) != ~0U)
+ goto found_middle;
+ result += 32;
+ size -= 32;
+ }
+ if (!size)
+ return result;
+ tmp = cpu_to_le32p(p);
+found_first:
+ tmp |= ~0U << size;
+found_middle:
+ return result + ffz(tmp);
+}
+
+/* Bitmap functions for the minix filesystem. */
+#define minix_test_and_set_bit(nr,addr) ext2_set_bit(nr,addr)
+#define minix_set_bit(nr,addr) ((void)ext2_set_bit(nr,addr))
+#define minix_test_and_clear_bit(nr,addr) ext2_clear_bit(nr,addr)
+#define minix_test_bit(nr,addr) ext2_test_bit(nr,addr)
+#define minix_find_first_zero_bit(addr,size) ext2_find_first_zero_bit(addr,size)
+
+#endif /* _PPC_BITOPS_H */
Code Review / kvmfornfv.git / blobdiff