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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-cris/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-cris/bitops.h')
-rw-r--r--include/asm-cris/bitops.h387
1 files changed, 387 insertions, 0 deletions
diff --git a/include/asm-cris/bitops.h b/include/asm-cris/bitops.h
new file mode 100644
index 00000000000..d7861115d73
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+++ b/include/asm-cris/bitops.h
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+/* asm/bitops.h for Linux/CRIS
+ *
+ * TODO: asm versions if speed is needed
+ *
+ * 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).
+ */
+
+#ifndef _CRIS_BITOPS_H
+#define _CRIS_BITOPS_H
+
+/* Currently this is unsuitable for consumption outside the kernel. */
+#ifdef __KERNEL__
+
+#include <asm/arch/bitops.h>
+#include <asm/system.h>
+#include <linux/compiler.h>
+
+/*
+ * Some hacks to defeat gcc over-optimizations..
+ */
+struct __dummy { unsigned long a[100]; };
+#define ADDR (*(struct __dummy *) addr)
+#define CONST_ADDR (*(const struct __dummy *) 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.
+ */
+
+#define set_bit(nr, addr) (void)test_and_set_bit(nr, addr)
+
+#define __set_bit(nr, addr) (void)__test_and_set_bit(nr, addr)
+
+/*
+ * 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.
+ */
+
+#define clear_bit(nr, addr) (void)test_and_clear_bit(nr, addr)
+
+#define __clear_bit(nr, addr) (void)__test_and_clear_bit(nr, addr)
+
+/*
+ * 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.
+ */
+
+#define change_bit(nr, addr) (void)test_and_change_bit(nr, addr)
+
+/*
+ * __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.
+ */
+
+#define __change_bit(nr, addr) (void)__test_and_change_bit(nr, addr)
+
+/**
+ * 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.
+ */
+
+extern inline int test_and_set_bit(int nr, void *addr)
+{
+ unsigned int mask, retval;
+ unsigned long flags;
+ unsigned int *adr = (unsigned int *)addr;
+
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ local_save_flags(flags);
+ local_irq_disable();
+ retval = (mask & *adr) != 0;
+ *adr |= mask;
+ local_irq_restore(flags);
+ return retval;
+}
+
+extern inline int __test_and_set_bit(int nr, void *addr)
+{
+ unsigned int mask, retval;
+ unsigned int *adr = (unsigned int *)addr;
+
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *adr) != 0;
+ *adr |= mask;
+ return retval;
+}
+
+/*
+ * clear_bit() doesn't provide any barrier for the compiler.
+ */
+#define smp_mb__before_clear_bit() barrier()
+#define smp_mb__after_clear_bit() barrier()
+
+/**
+ * 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.
+ */
+
+extern inline int test_and_clear_bit(int nr, void *addr)
+{
+ unsigned int mask, retval;
+ unsigned long flags;
+ unsigned int *adr = (unsigned int *)addr;
+
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ local_save_flags(flags);
+ local_irq_disable();
+ retval = (mask & *adr) != 0;
+ *adr &= ~mask;
+ 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.
+ */
+
+extern inline int __test_and_clear_bit(int nr, void *addr)
+{
+ unsigned int mask, retval;
+ unsigned int *adr = (unsigned int *)addr;
+
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *adr) != 0;
+ *adr &= ~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.
+ */
+
+extern inline int test_and_change_bit(int nr, void *addr)
+{
+ unsigned int mask, retval;
+ unsigned long flags;
+ unsigned int *adr = (unsigned int *)addr;
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ local_save_flags(flags);
+ local_irq_disable();
+ retval = (mask & *adr) != 0;
+ *adr ^= mask;
+ local_irq_restore(flags);
+ return retval;
+}
+
+/* WARNING: non atomic and it can be reordered! */
+
+extern inline int __test_and_change_bit(int nr, void *addr)
+{
+ unsigned int mask, retval;
+ unsigned int *adr = (unsigned int *)addr;
+
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ retval = (mask & *adr) != 0;
+ *adr ^= mask;
+
+ return retval;
+}
+
+/**
+ * test_bit - Determine whether a bit is set
+ * @nr: bit number to test
+ * @addr: Address to start counting from
+ *
+ * This routine doesn't need to be atomic.
+ */
+
+extern inline int test_bit(int nr, const void *addr)
+{
+ unsigned int mask;
+ unsigned int *adr = (unsigned int *)addr;
+
+ adr += nr >> 5;
+ mask = 1 << (nr & 0x1f);
+ return ((mask & *adr) != 0);
+}
+
+/*
+ * Find-bit routines..
+ */
+
+/*
+ * Since we define it "external", it collides with the built-in
+ * definition, which doesn't have the same semantics. We don't want to
+ * use -fno-builtin, so just hide the name ffs.
+ */
+#define ffs kernel_ffs
+
+/*
+ * fls: find last bit set.
+ */
+
+#define fls(x) generic_fls(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 hweight32(x) generic_hweight32(x)
+#define hweight16(x) generic_hweight16(x)
+#define hweight8(x) generic_hweight8(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
+ */
+extern 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);
+}
+
+/**
+ * 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
+ */
+static __inline__ int find_next_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 << 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 >> (32 - size));
+ if (tmp == 0UL) /* Are any bits set? */
+ return result + size; /* Nope. */
+found_middle:
+ return result + __ffs(tmp);
+}
+
+/**
+ * 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.
+ */
+
+#define find_first_zero_bit(addr, size) \
+ find_next_zero_bit((addr), (size), 0)
+#define find_first_bit(addr, size) \
+ find_next_bit((addr), (size), 0)
+
+#define ext2_set_bit test_and_set_bit
+#define ext2_set_bit_atomic(l,n,a) test_and_set_bit(n,a)
+#define ext2_clear_bit test_and_clear_bit
+#define ext2_clear_bit_atomic(l,n,a) test_and_clear_bit(n,a)
+#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_set_bit(nr,addr) test_and_set_bit(nr,addr)
+#define minix_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)
+
+extern inline int sched_find_first_bit(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 (unlikely(b[3]))
+ return __ffs(b[3]) + 96;
+ if (b[4])
+ return __ffs(b[4]) + 128;
+ return __ffs(b[5]) + 32 + 128;
+}
+
+#endif /* __KERNEL__ */
+
+#endif /* _CRIS_BITOPS_H */