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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-11 08:27:49 +0000
commitace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch)
treeb2d64bc10158fdd5497876388cd68142ca374ed3 /arch/ia64/include/uapi/asm/cmpxchg.h
parentInitial commit. (diff)
downloadlinux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz
linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'arch/ia64/include/uapi/asm/cmpxchg.h')
-rw-r--r--arch/ia64/include/uapi/asm/cmpxchg.h138
1 files changed, 138 insertions, 0 deletions
diff --git a/arch/ia64/include/uapi/asm/cmpxchg.h b/arch/ia64/include/uapi/asm/cmpxchg.h
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+++ b/arch/ia64/include/uapi/asm/cmpxchg.h
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+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+#ifndef _UAPI_ASM_IA64_CMPXCHG_H
+#define _UAPI_ASM_IA64_CMPXCHG_H
+
+/*
+ * Compare/Exchange, forked from asm/intrinsics.h
+ * which was:
+ *
+ * Copyright (C) 2002-2003 Hewlett-Packard Co
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ */
+
+#ifndef __ASSEMBLY__
+
+#include <linux/types.h>
+/* include compiler specific intrinsics */
+#include <asm/ia64regs.h>
+#include <asm/gcc_intrin.h>
+
+/*
+ * This function doesn't exist, so you'll get a linker error if
+ * something tries to do an invalid xchg().
+ */
+extern void ia64_xchg_called_with_bad_pointer(void);
+
+#define __arch_xchg(x, ptr, size) \
+({ \
+ unsigned long __xchg_result; \
+ \
+ switch (size) { \
+ case 1: \
+ __xchg_result = ia64_xchg1((__u8 __force *)ptr, x); \
+ break; \
+ \
+ case 2: \
+ __xchg_result = ia64_xchg2((__u16 __force *)ptr, x); \
+ break; \
+ \
+ case 4: \
+ __xchg_result = ia64_xchg4((__u32 __force *)ptr, x); \
+ break; \
+ \
+ case 8: \
+ __xchg_result = ia64_xchg8((__u64 __force *)ptr, x); \
+ break; \
+ default: \
+ ia64_xchg_called_with_bad_pointer(); \
+ } \
+ (__typeof__ (*(ptr)) __force) __xchg_result; \
+})
+
+#ifndef __KERNEL__
+#define xchg(ptr, x) \
+({(__typeof__(*(ptr))) __arch_xchg((unsigned long) (x), (ptr), sizeof(*(ptr)));})
+#endif
+
+/*
+ * Atomic compare and exchange. Compare OLD with MEM, if identical,
+ * store NEW in MEM. Return the initial value in MEM. Success is
+ * indicated by comparing RETURN with OLD.
+ */
+
+/*
+ * This function doesn't exist, so you'll get a linker error
+ * if something tries to do an invalid cmpxchg().
+ */
+extern long ia64_cmpxchg_called_with_bad_pointer(void);
+
+#define ia64_cmpxchg(sem, ptr, old, new, size) \
+({ \
+ __u64 _o_, _r_; \
+ \
+ switch (size) { \
+ case 1: \
+ _o_ = (__u8) (long __force) (old); \
+ break; \
+ case 2: \
+ _o_ = (__u16) (long __force) (old); \
+ break; \
+ case 4: \
+ _o_ = (__u32) (long __force) (old); \
+ break; \
+ case 8: \
+ _o_ = (__u64) (long __force) (old); \
+ break; \
+ default: \
+ break; \
+ } \
+ switch (size) { \
+ case 1: \
+ _r_ = ia64_cmpxchg1_##sem((__u8 __force *) ptr, new, _o_); \
+ break; \
+ \
+ case 2: \
+ _r_ = ia64_cmpxchg2_##sem((__u16 __force *) ptr, new, _o_); \
+ break; \
+ \
+ case 4: \
+ _r_ = ia64_cmpxchg4_##sem((__u32 __force *) ptr, new, _o_); \
+ break; \
+ \
+ case 8: \
+ _r_ = ia64_cmpxchg8_##sem((__u64 __force *) ptr, new, _o_); \
+ break; \
+ \
+ default: \
+ _r_ = ia64_cmpxchg_called_with_bad_pointer(); \
+ break; \
+ } \
+ (__typeof__(old) __force) _r_; \
+})
+
+#define cmpxchg_acq(ptr, o, n) \
+ ia64_cmpxchg(acq, (ptr), (o), (n), sizeof(*(ptr)))
+#define cmpxchg_rel(ptr, o, n) \
+ ia64_cmpxchg(rel, (ptr), (o), (n), sizeof(*(ptr)))
+
+/*
+ * Worse still - early processor implementations actually just ignored
+ * the acquire/release and did a full fence all the time. Unfortunately
+ * this meant a lot of badly written code that used .acq when they really
+ * wanted .rel became legacy out in the wild - so when we made a cpu
+ * that strictly did the .acq or .rel ... all that code started breaking - so
+ * we had to back-pedal and keep the "legacy" behavior of a full fence :-(
+ */
+
+#ifndef __KERNEL__
+/* for compatibility with other platforms: */
+#define cmpxchg(ptr, o, n) cmpxchg_acq((ptr), (o), (n))
+#define cmpxchg64(ptr, o, n) cmpxchg_acq((ptr), (o), (n))
+
+#define cmpxchg_local cmpxchg
+#define cmpxchg64_local cmpxchg64
+#endif
+
+#endif /* !__ASSEMBLY__ */
+
+#endif /* _UAPI_ASM_IA64_CMPXCHG_H */