fs: use kmem_cache_zalloc instead
[pv_ops_mirror.git] / include / asm-xtensa / bitops.h
blob1c1e0d933eea8311db44907231d94a62b025c334
1 /*
2 * include/asm-xtensa/bitops.h
4 * Atomic operations that C can't guarantee us.Useful for resource counting etc.
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file "COPYING" in the main directory of this archive
8 * for more details.
10 * Copyright (C) 2001 - 2007 Tensilica Inc.
13 #ifndef _XTENSA_BITOPS_H
14 #define _XTENSA_BITOPS_H
16 #ifdef __KERNEL__
18 #include <asm/processor.h>
19 #include <asm/byteorder.h>
20 #include <asm/system.h>
22 #ifdef CONFIG_SMP
23 # error SMP not supported on this architecture
24 #endif
26 #define smp_mb__before_clear_bit() barrier()
27 #define smp_mb__after_clear_bit() barrier()
29 #include <asm-generic/bitops/atomic.h>
30 #include <asm-generic/bitops/non-atomic.h>
32 #if XCHAL_HAVE_NSA
34 static inline unsigned long __cntlz (unsigned long x)
36 int lz;
37 asm ("nsau %0, %1" : "=r" (lz) : "r" (x));
38 return lz;
42 * ffz: Find first zero in word. Undefined if no zero exists.
43 * bit 0 is the LSB of addr; bit 32 is the LSB of (addr+1).
46 static inline int ffz(unsigned long x)
48 return 31 - __cntlz(~x & -~x);
52 * __ffs: Find first bit set in word. Return 0 for bit 0
55 static inline int __ffs(unsigned long x)
57 return 31 - __cntlz(x & -x);
61 * ffs: Find first bit set in word. This is defined the same way as
62 * the libc and compiler builtin ffs routines, therefore
63 * differs in spirit from the above ffz (man ffs).
66 static inline int ffs(unsigned long x)
68 return 32 - __cntlz(x & -x);
72 * fls: Find last (most-significant) bit set in word.
73 * Note fls(0) = 0, fls(1) = 1, fls(0x80000000) = 32.
76 static inline int fls (unsigned int x)
78 return 32 - __cntlz(x);
81 #else
83 /* Use the generic implementation if we don't have the nsa/nsau instructions. */
85 # include <asm-generic/bitops/ffs.h>
86 # include <asm-generic/bitops/__ffs.h>
87 # include <asm-generic/bitops/ffz.h>
88 # include <asm-generic/bitops/fls.h>
90 #endif
92 #include <asm-generic/bitops/fls64.h>
93 #include <asm-generic/bitops/find.h>
94 #include <asm-generic/bitops/ext2-non-atomic.h>
96 #ifdef __XTENSA_EL__
97 # define ext2_set_bit_atomic(lock,nr,addr) \
98 test_and_set_bit((nr), (unsigned long*)(addr))
99 # define ext2_clear_bit_atomic(lock,nr,addr) \
100 test_and_clear_bit((nr), (unsigned long*)(addr))
101 #elif defined(__XTENSA_EB__)
102 # define ext2_set_bit_atomic(lock,nr,addr) \
103 test_and_set_bit((nr) ^ 0x18, (unsigned long*)(addr))
104 # define ext2_clear_bit_atomic(lock,nr,addr) \
105 test_and_clear_bit((nr) ^ 0x18, (unsigned long*)(addr))
106 #else
107 # error processor byte order undefined!
108 #endif
110 #include <asm-generic/bitops/hweight.h>
111 #include <asm-generic/bitops/sched.h>
112 #include <asm-generic/bitops/minix.h>
114 #endif /* __KERNEL__ */
116 #endif /* _XTENSA_BITOPS_H */