diff options
Diffstat (limited to 'arch/powerpc/include/asm/kvm_book3s_64.h')
| -rw-r--r-- | arch/powerpc/include/asm/kvm_book3s_64.h | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/arch/powerpc/include/asm/kvm_book3s_64.h b/arch/powerpc/include/asm/kvm_book3s_64.h index fa3dc79af70..300ec04a838 100644 --- a/arch/powerpc/include/asm/kvm_book3s_64.h +++ b/arch/powerpc/include/asm/kvm_book3s_64.h @@ -43,6 +43,31 @@ static inline void svcpu_put(struct kvmppc_book3s_shadow_vcpu *svcpu) #define HPT_HASH_MASK (HPT_NPTEG - 1) #endif +/* + * We use a lock bit in HPTE dword 0 to synchronize updates and + * accesses to each HPTE, and another bit to indicate non-present + * HPTEs. + */ +#define HPTE_V_HVLOCK 0x40UL + +static inline long try_lock_hpte(unsigned long *hpte, unsigned long bits) +{ + unsigned long tmp, old; + + asm volatile(" ldarx %0,0,%2\n" + " and. %1,%0,%3\n" + " bne 2f\n" + " ori %0,%0,%4\n" + " stdcx. %0,0,%2\n" + " beq+ 2f\n" + " li %1,%3\n" + "2: isync" + : "=&r" (tmp), "=&r" (old) + : "r" (hpte), "r" (bits), "i" (HPTE_V_HVLOCK) + : "cc", "memory"); + return old == 0; +} + static inline unsigned long compute_tlbie_rb(unsigned long v, unsigned long r, unsigned long pte_index) { |