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-rw-r--r--include/asm-generic/atomic.h3
-rw-r--r--include/asm-generic/dma-mapping.h2
-rw-r--r--include/asm-generic/futex.h53
-rw-r--r--include/asm-generic/ioctl.h80
-rw-r--r--include/asm-generic/mutex-dec.h110
-rw-r--r--include/asm-generic/mutex-null.h24
-rw-r--r--include/asm-generic/mutex-xchg.h117
7 files changed, 387 insertions, 2 deletions
diff --git a/include/asm-generic/atomic.h b/include/asm-generic/atomic.h
index e0a28b925ef0..42a95d9a0641 100644
--- a/include/asm-generic/atomic.h
+++ b/include/asm-generic/atomic.h
@@ -8,6 +8,7 @@
8 * edit all arch specific atomic.h files. 8 * edit all arch specific atomic.h files.
9 */ 9 */
10 10
11#include <asm/types.h>
11 12
12/* 13/*
13 * Suppport for atomic_long_t 14 * Suppport for atomic_long_t
@@ -34,7 +35,7 @@ static inline void atomic_long_set(atomic_long_t *l, long i)
34{ 35{
35 atomic64_t *v = (atomic64_t *)l; 36 atomic64_t *v = (atomic64_t *)l;
36 37
37 atomic_set(v, i); 38 atomic64_set(v, i);
38} 39}
39 40
40static inline void atomic_long_inc(atomic_long_t *l) 41static inline void atomic_long_inc(atomic_long_t *l)
diff --git a/include/asm-generic/dma-mapping.h b/include/asm-generic/dma-mapping.h
index 747d790295f3..1b356207712c 100644
--- a/include/asm-generic/dma-mapping.h
+++ b/include/asm-generic/dma-mapping.h
@@ -274,7 +274,7 @@ dma_get_cache_alignment(void)
274{ 274{
275 /* no easy way to get cache size on all processors, so return 275 /* no easy way to get cache size on all processors, so return
276 * the maximum possible, to be safe */ 276 * the maximum possible, to be safe */
277 return (1 << L1_CACHE_SHIFT_MAX); 277 return (1 << INTERNODE_CACHE_SHIFT);
278} 278}
279 279
280static inline void 280static inline void
diff --git a/include/asm-generic/futex.h b/include/asm-generic/futex.h
new file mode 100644
index 000000000000..3ae2c7347549
--- /dev/null
+++ b/include/asm-generic/futex.h
@@ -0,0 +1,53 @@
1#ifndef _ASM_GENERIC_FUTEX_H
2#define _ASM_GENERIC_FUTEX_H
3
4#ifdef __KERNEL__
5
6#include <linux/futex.h>
7#include <asm/errno.h>
8#include <asm/uaccess.h>
9
10static inline int
11futex_atomic_op_inuser (int encoded_op, int __user *uaddr)
12{
13 int op = (encoded_op >> 28) & 7;
14 int cmp = (encoded_op >> 24) & 15;
15 int oparg = (encoded_op << 8) >> 20;
16 int cmparg = (encoded_op << 20) >> 20;
17 int oldval = 0, ret;
18 if (encoded_op & (FUTEX_OP_OPARG_SHIFT << 28))
19 oparg = 1 << oparg;
20
21 if (! access_ok (VERIFY_WRITE, uaddr, sizeof(int)))
22 return -EFAULT;
23
24 inc_preempt_count();
25
26 switch (op) {
27 case FUTEX_OP_SET:
28 case FUTEX_OP_ADD:
29 case FUTEX_OP_OR:
30 case FUTEX_OP_ANDN:
31 case FUTEX_OP_XOR:
32 default:
33 ret = -ENOSYS;
34 }
35
36 dec_preempt_count();
37
38 if (!ret) {
39 switch (cmp) {
40 case FUTEX_OP_CMP_EQ: ret = (oldval == cmparg); break;
41 case FUTEX_OP_CMP_NE: ret = (oldval != cmparg); break;
42 case FUTEX_OP_CMP_LT: ret = (oldval < cmparg); break;
43 case FUTEX_OP_CMP_GE: ret = (oldval >= cmparg); break;
44 case FUTEX_OP_CMP_LE: ret = (oldval <= cmparg); break;
45 case FUTEX_OP_CMP_GT: ret = (oldval > cmparg); break;
46 default: ret = -ENOSYS;
47 }
48 }
49 return ret;
50}
51
52#endif
53#endif
diff --git a/include/asm-generic/ioctl.h b/include/asm-generic/ioctl.h
new file mode 100644
index 000000000000..cd027298beb1
--- /dev/null
+++ b/include/asm-generic/ioctl.h
@@ -0,0 +1,80 @@
1#ifndef _ASM_GENERIC_IOCTL_H
2#define _ASM_GENERIC_IOCTL_H
3
4/* ioctl command encoding: 32 bits total, command in lower 16 bits,
5 * size of the parameter structure in the lower 14 bits of the
6 * upper 16 bits.
7 * Encoding the size of the parameter structure in the ioctl request
8 * is useful for catching programs compiled with old versions
9 * and to avoid overwriting user space outside the user buffer area.
10 * The highest 2 bits are reserved for indicating the ``access mode''.
11 * NOTE: This limits the max parameter size to 16kB -1 !
12 */
13
14/*
15 * The following is for compatibility across the various Linux
16 * platforms. The generic ioctl numbering scheme doesn't really enforce
17 * a type field. De facto, however, the top 8 bits of the lower 16
18 * bits are indeed used as a type field, so we might just as well make
19 * this explicit here. Please be sure to use the decoding macros
20 * below from now on.
21 */
22#define _IOC_NRBITS 8
23#define _IOC_TYPEBITS 8
24#define _IOC_SIZEBITS 14
25#define _IOC_DIRBITS 2
26
27#define _IOC_NRMASK ((1 << _IOC_NRBITS)-1)
28#define _IOC_TYPEMASK ((1 << _IOC_TYPEBITS)-1)
29#define _IOC_SIZEMASK ((1 << _IOC_SIZEBITS)-1)
30#define _IOC_DIRMASK ((1 << _IOC_DIRBITS)-1)
31
32#define _IOC_NRSHIFT 0
33#define _IOC_TYPESHIFT (_IOC_NRSHIFT+_IOC_NRBITS)
34#define _IOC_SIZESHIFT (_IOC_TYPESHIFT+_IOC_TYPEBITS)
35#define _IOC_DIRSHIFT (_IOC_SIZESHIFT+_IOC_SIZEBITS)
36
37/*
38 * Direction bits.
39 */
40#define _IOC_NONE 0U
41#define _IOC_WRITE 1U
42#define _IOC_READ 2U
43
44#define _IOC(dir,type,nr,size) \
45 (((dir) << _IOC_DIRSHIFT) | \
46 ((type) << _IOC_TYPESHIFT) | \
47 ((nr) << _IOC_NRSHIFT) | \
48 ((size) << _IOC_SIZESHIFT))
49
50/* provoke compile error for invalid uses of size argument */
51extern unsigned int __invalid_size_argument_for_IOC;
52#define _IOC_TYPECHECK(t) \
53 ((sizeof(t) == sizeof(t[1]) && \
54 sizeof(t) < (1 << _IOC_SIZEBITS)) ? \
55 sizeof(t) : __invalid_size_argument_for_IOC)
56
57/* used to create numbers */
58#define _IO(type,nr) _IOC(_IOC_NONE,(type),(nr),0)
59#define _IOR(type,nr,size) _IOC(_IOC_READ,(type),(nr),(_IOC_TYPECHECK(size)))
60#define _IOW(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),(_IOC_TYPECHECK(size)))
61#define _IOWR(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),(_IOC_TYPECHECK(size)))
62#define _IOR_BAD(type,nr,size) _IOC(_IOC_READ,(type),(nr),sizeof(size))
63#define _IOW_BAD(type,nr,size) _IOC(_IOC_WRITE,(type),(nr),sizeof(size))
64#define _IOWR_BAD(type,nr,size) _IOC(_IOC_READ|_IOC_WRITE,(type),(nr),sizeof(size))
65
66/* used to decode ioctl numbers.. */
67#define _IOC_DIR(nr) (((nr) >> _IOC_DIRSHIFT) & _IOC_DIRMASK)
68#define _IOC_TYPE(nr) (((nr) >> _IOC_TYPESHIFT) & _IOC_TYPEMASK)
69#define _IOC_NR(nr) (((nr) >> _IOC_NRSHIFT) & _IOC_NRMASK)
70#define _IOC_SIZE(nr) (((nr) >> _IOC_SIZESHIFT) & _IOC_SIZEMASK)
71
72/* ...and for the drivers/sound files... */
73
74#define IOC_IN (_IOC_WRITE << _IOC_DIRSHIFT)
75#define IOC_OUT (_IOC_READ << _IOC_DIRSHIFT)
76#define IOC_INOUT ((_IOC_WRITE|_IOC_READ) << _IOC_DIRSHIFT)
77#define IOCSIZE_MASK (_IOC_SIZEMASK << _IOC_SIZESHIFT)
78#define IOCSIZE_SHIFT (_IOC_SIZESHIFT)
79
80#endif /* _ASM_GENERIC_IOCTL_H */
diff --git a/include/asm-generic/mutex-dec.h b/include/asm-generic/mutex-dec.h
new file mode 100644
index 000000000000..40c6d1f86598
--- /dev/null
+++ b/include/asm-generic/mutex-dec.h
@@ -0,0 +1,110 @@
1/*
2 * asm-generic/mutex-dec.h
3 *
4 * Generic implementation of the mutex fastpath, based on atomic
5 * decrement/increment.
6 */
7#ifndef _ASM_GENERIC_MUTEX_DEC_H
8#define _ASM_GENERIC_MUTEX_DEC_H
9
10/**
11 * __mutex_fastpath_lock - try to take the lock by moving the count
12 * from 1 to a 0 value
13 * @count: pointer of type atomic_t
14 * @fail_fn: function to call if the original value was not 1
15 *
16 * Change the count from 1 to a value lower than 1, and call <fail_fn> if
17 * it wasn't 1 originally. This function MUST leave the value lower than
18 * 1 even when the "1" assertion wasn't true.
19 */
20#define __mutex_fastpath_lock(count, fail_fn) \
21do { \
22 if (unlikely(atomic_dec_return(count) < 0)) \
23 fail_fn(count); \
24 else \
25 smp_mb(); \
26} while (0)
27
28/**
29 * __mutex_fastpath_lock_retval - try to take the lock by moving the count
30 * from 1 to a 0 value
31 * @count: pointer of type atomic_t
32 * @fail_fn: function to call if the original value was not 1
33 *
34 * Change the count from 1 to a value lower than 1, and call <fail_fn> if
35 * it wasn't 1 originally. This function returns 0 if the fastpath succeeds,
36 * or anything the slow path function returns.
37 */
38static inline int
39__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
40{
41 if (unlikely(atomic_dec_return(count) < 0))
42 return fail_fn(count);
43 else {
44 smp_mb();
45 return 0;
46 }
47}
48
49/**
50 * __mutex_fastpath_unlock - try to promote the count from 0 to 1
51 * @count: pointer of type atomic_t
52 * @fail_fn: function to call if the original value was not 0
53 *
54 * Try to promote the count from 0 to 1. If it wasn't 0, call <fail_fn>.
55 * In the failure case, this function is allowed to either set the value to
56 * 1, or to set it to a value lower than 1.
57 *
58 * If the implementation sets it to a value of lower than 1, then the
59 * __mutex_slowpath_needs_to_unlock() macro needs to return 1, it needs
60 * to return 0 otherwise.
61 */
62#define __mutex_fastpath_unlock(count, fail_fn) \
63do { \
64 smp_mb(); \
65 if (unlikely(atomic_inc_return(count) <= 0)) \
66 fail_fn(count); \
67} while (0)
68
69#define __mutex_slowpath_needs_to_unlock() 1
70
71/**
72 * __mutex_fastpath_trylock - try to acquire the mutex, without waiting
73 *
74 * @count: pointer of type atomic_t
75 * @fail_fn: fallback function
76 *
77 * Change the count from 1 to a value lower than 1, and return 0 (failure)
78 * if it wasn't 1 originally, or return 1 (success) otherwise. This function
79 * MUST leave the value lower than 1 even when the "1" assertion wasn't true.
80 * Additionally, if the value was < 0 originally, this function must not leave
81 * it to 0 on failure.
82 *
83 * If the architecture has no effective trylock variant, it should call the
84 * <fail_fn> spinlock-based trylock variant unconditionally.
85 */
86static inline int
87__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
88{
89 /*
90 * We have two variants here. The cmpxchg based one is the best one
91 * because it never induce a false contention state. It is included
92 * here because architectures using the inc/dec algorithms over the
93 * xchg ones are much more likely to support cmpxchg natively.
94 *
95 * If not we fall back to the spinlock based variant - that is
96 * just as efficient (and simpler) as a 'destructive' probing of
97 * the mutex state would be.
98 */
99#ifdef __HAVE_ARCH_CMPXCHG
100 if (likely(atomic_cmpxchg(count, 1, 0) == 1)) {
101 smp_mb();
102 return 1;
103 }
104 return 0;
105#else
106 return fail_fn(count);
107#endif
108}
109
110#endif
diff --git a/include/asm-generic/mutex-null.h b/include/asm-generic/mutex-null.h
new file mode 100644
index 000000000000..5cf8b7ce0c45
--- /dev/null
+++ b/include/asm-generic/mutex-null.h
@@ -0,0 +1,24 @@
1/*
2 * asm-generic/mutex-null.h
3 *
4 * Generic implementation of the mutex fastpath, based on NOP :-)
5 *
6 * This is used by the mutex-debugging infrastructure, but it can also
7 * be used by architectures that (for whatever reason) want to use the
8 * spinlock based slowpath.
9 */
10#ifndef _ASM_GENERIC_MUTEX_NULL_H
11#define _ASM_GENERIC_MUTEX_NULL_H
12
13/* extra parameter only needed for mutex debugging: */
14#ifndef __IP__
15# define __IP__
16#endif
17
18#define __mutex_fastpath_lock(count, fail_fn) fail_fn(count __RET_IP__)
19#define __mutex_fastpath_lock_retval(count, fail_fn) fail_fn(count __RET_IP__)
20#define __mutex_fastpath_unlock(count, fail_fn) fail_fn(count __RET_IP__)
21#define __mutex_fastpath_trylock(count, fail_fn) fail_fn(count)
22#define __mutex_slowpath_needs_to_unlock() 1
23
24#endif
diff --git a/include/asm-generic/mutex-xchg.h b/include/asm-generic/mutex-xchg.h
new file mode 100644
index 000000000000..1d24f47e6c48
--- /dev/null
+++ b/include/asm-generic/mutex-xchg.h
@@ -0,0 +1,117 @@
1/*
2 * asm-generic/mutex-xchg.h
3 *
4 * Generic implementation of the mutex fastpath, based on xchg().
5 *
6 * NOTE: An xchg based implementation is less optimal than an atomic
7 * decrement/increment based implementation. If your architecture
8 * has a reasonable atomic dec/inc then you should probably use
9 * asm-generic/mutex-dec.h instead, or you could open-code an
10 * optimized version in asm/mutex.h.
11 */
12#ifndef _ASM_GENERIC_MUTEX_XCHG_H
13#define _ASM_GENERIC_MUTEX_XCHG_H
14
15/**
16 * __mutex_fastpath_lock - try to take the lock by moving the count
17 * from 1 to a 0 value
18 * @count: pointer of type atomic_t
19 * @fail_fn: function to call if the original value was not 1
20 *
21 * Change the count from 1 to a value lower than 1, and call <fail_fn> if it
22 * wasn't 1 originally. This function MUST leave the value lower than 1
23 * even when the "1" assertion wasn't true.
24 */
25#define __mutex_fastpath_lock(count, fail_fn) \
26do { \
27 if (unlikely(atomic_xchg(count, 0) != 1)) \
28 fail_fn(count); \
29 else \
30 smp_mb(); \
31} while (0)
32
33
34/**
35 * __mutex_fastpath_lock_retval - try to take the lock by moving the count
36 * from 1 to a 0 value
37 * @count: pointer of type atomic_t
38 * @fail_fn: function to call if the original value was not 1
39 *
40 * Change the count from 1 to a value lower than 1, and call <fail_fn> if it
41 * wasn't 1 originally. This function returns 0 if the fastpath succeeds,
42 * or anything the slow path function returns
43 */
44static inline int
45__mutex_fastpath_lock_retval(atomic_t *count, int (*fail_fn)(atomic_t *))
46{
47 if (unlikely(atomic_xchg(count, 0) != 1))
48 return fail_fn(count);
49 else {
50 smp_mb();
51 return 0;
52 }
53}
54
55/**
56 * __mutex_fastpath_unlock - try to promote the mutex from 0 to 1
57 * @count: pointer of type atomic_t
58 * @fail_fn: function to call if the original value was not 0
59 *
60 * try to promote the mutex from 0 to 1. if it wasn't 0, call <function>
61 * In the failure case, this function is allowed to either set the value to
62 * 1, or to set it to a value lower than one.
63 * If the implementation sets it to a value of lower than one, the
64 * __mutex_slowpath_needs_to_unlock() macro needs to return 1, it needs
65 * to return 0 otherwise.
66 */
67#define __mutex_fastpath_unlock(count, fail_fn) \
68do { \
69 smp_mb(); \
70 if (unlikely(atomic_xchg(count, 1) != 0)) \
71 fail_fn(count); \
72} while (0)
73
74#define __mutex_slowpath_needs_to_unlock() 0
75
76/**
77 * __mutex_fastpath_trylock - try to acquire the mutex, without waiting
78 *
79 * @count: pointer of type atomic_t
80 * @fail_fn: spinlock based trylock implementation
81 *
82 * Change the count from 1 to a value lower than 1, and return 0 (failure)
83 * if it wasn't 1 originally, or return 1 (success) otherwise. This function
84 * MUST leave the value lower than 1 even when the "1" assertion wasn't true.
85 * Additionally, if the value was < 0 originally, this function must not leave
86 * it to 0 on failure.
87 *
88 * If the architecture has no effective trylock variant, it should call the
89 * <fail_fn> spinlock-based trylock variant unconditionally.
90 */
91static inline int
92__mutex_fastpath_trylock(atomic_t *count, int (*fail_fn)(atomic_t *))
93{
94 int prev = atomic_xchg(count, 0);
95
96 if (unlikely(prev < 0)) {
97 /*
98 * The lock was marked contended so we must restore that
99 * state. If while doing so we get back a prev value of 1
100 * then we just own it.
101 *
102 * [ In the rare case of the mutex going to 1, to 0, to -1
103 * and then back to 0 in this few-instructions window,
104 * this has the potential to trigger the slowpath for the
105 * owner's unlock path needlessly, but that's not a problem
106 * in practice. ]
107 */
108 prev = atomic_xchg(count, prev);
109 if (prev < 0)
110 prev = 0;
111 }
112 smp_mb();
113
114 return prev;
115}
116
117#endif
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