#ifndef __ARCH_M68K_CMPXCHG__ #define __ARCH_M68K_CMPXCHG__ #include <linux/irqflags.h> struct __xchg_dummy { unsigned long a[100]; }; #define __xg(x) ((volatile struct __xchg_dummy *)(x)) extern unsigned long __invalid_xchg_size(unsigned long, volatile void *, int); #ifndef CONFIG_RMW_INSNS static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { unsigned long flags, tmp; local_irq_save(flags); switch (size) { case 1: tmp = *(u8 *)ptr; *(u8 *)ptr = x; x = tmp; break; case 2: tmp = *(u16 *)ptr; *(u16 *)ptr = x; x = tmp; break; case 4: tmp = *(u32 *)ptr; *(u32 *)ptr = x; x = tmp; break; default: tmp = __invalid_xchg_size(x, ptr, size); break; } local_irq_restore(flags); return x; } #else static inline unsigned long __xchg(unsigned long x, volatile void * ptr, int size) { switch (size) { case 1: __asm__ __volatile__ ("moveb %2,%0\n\t" "1:\n\t" "casb %0,%1,%2\n\t" "jne 1b" : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; case 2: __asm__ __volatile__ ("movew %2,%0\n\t" "1:\n\t" "casw %0,%1,%2\n\t" "jne 1b" : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; case 4: __asm__ __volatile__ ("movel %2,%0\n\t" "1:\n\t" "casl %0,%1,%2\n\t" "jne 1b" : "=&d" (x) : "d" (x), "m" (*__xg(ptr)) : "memory"); break; default: x = __invalid_xchg_size(x, ptr, size); break; } return x; } #endif #define xchg(ptr,x) ((__typeof__(*(ptr)))__xchg((unsigned long)(x),(ptr),sizeof(*(ptr)))) #include <asm-generic/cmpxchg-local.h> #define cmpxchg64_local(ptr, o, n) __cmpxchg64_local_generic((ptr), (o), (n)) extern unsigned long __invalid_cmpxchg_size(volatile void *, unsigned long, unsigned long, int); /* * 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. */ #ifdef CONFIG_RMW_INSNS #define __HAVE_ARCH_CMPXCHG 1 static inline unsigned long __cmpxchg(volatile void *p, unsigned long old, unsigned long new, int size) { switch (size) { case 1: __asm__ __volatile__ ("casb %0,%2,%1" : "=d" (old), "=m" (*(char *)p) : "d" (new), "0" (old), "m" (*(char *)p)); break; case 2: __asm__ __volatile__ ("casw %0,%2,%1" : "=d" (old), "=m" (*(short *)p) : "d" (new), "0" (old), "m" (*(short *)p)); break; case 4: __asm__ __volatile__ ("casl %0,%2,%1" : "=d" (old), "=m" (*(int *)p) : "d" (new), "0" (old), "m" (*(int *)p)); break; default: old = __invalid_cmpxchg_size(p, old, new, size); break; } return old; } #define cmpxchg(ptr, o, n) \ ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \ (unsigned long)(n), sizeof(*(ptr)))) #define cmpxchg_local(ptr, o, n) \ ((__typeof__(*(ptr)))__cmpxchg((ptr), (unsigned long)(o), \ (unsigned long)(n), sizeof(*(ptr)))) #define cmpxchg64(ptr, o, n) cmpxchg64_local((ptr), (o), (n)) #else /* * cmpxchg_local and cmpxchg64_local are atomic wrt current CPU. Always make * them available. */ #define cmpxchg_local(ptr, o, n) \ ((__typeof__(*(ptr)))__cmpxchg_local_generic((ptr), (unsigned long)(o),\ (unsigned long)(n), sizeof(*(ptr)))) #include <asm-generic/cmpxchg.h> #endif #endif /* __ARCH_M68K_CMPXCHG__ */