From 3e2f65d57a0c1897fcc3287eeb41f117f4d021e5 Mon Sep 17 00:00:00 2001 From: Gleb Natapov Date: Wed, 25 Aug 2010 12:47:42 +0300 Subject: [PATCH] KVM: x86 emulator: move string instruction completion check into separate function Signed-off-by: Gleb Natapov Signed-off-by: Marcelo Tosatti --- arch/x86/kvm/emulate.c | 37 ++++++++++++++++++++++++------------- 1 file changed, 24 insertions(+), 13 deletions(-) diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c index 42d42ca2c37b..3dcbc1d0a59d 100644 --- a/arch/x86/kvm/emulate.c +++ b/arch/x86/kvm/emulate.c @@ -2933,6 +2933,28 @@ done: return (rc == X86EMUL_UNHANDLEABLE) ? -1 : 0; } +static bool string_insn_completed(struct x86_emulate_ctxt *ctxt) +{ + struct decode_cache *c = &ctxt->decode; + + /* The second termination condition only applies for REPE + * and REPNE. Test if the repeat string operation prefix is + * REPE/REPZ or REPNE/REPNZ and if it's the case it tests the + * corresponding termination condition according to: + * - if REPE/REPZ and ZF = 0 then done + * - if REPNE/REPNZ and ZF = 1 then done + */ + if (((c->b == 0xa6) || (c->b == 0xa7) || + (c->b == 0xae) || (c->b == 0xaf)) + && (((c->rep_prefix == REPE_PREFIX) && + ((ctxt->eflags & EFLG_ZF) == 0)) + || ((c->rep_prefix == REPNE_PREFIX) && + ((ctxt->eflags & EFLG_ZF) == EFLG_ZF)))) + return true; + + return false; +} + int x86_emulate_insn(struct x86_emulate_ctxt *ctxt) { @@ -3423,19 +3445,8 @@ writeback: if (c->rep_prefix && (c->d & String)) { struct read_cache *r = &ctxt->decode.io_read; register_address_increment(c, &c->regs[VCPU_REGS_RCX], -1); - /* The second termination condition only applies for REPE - * and REPNE. Test if the repeat string operation prefix is - * REPE/REPZ or REPNE/REPNZ and if it's the case it tests the - * corresponding termination condition according to: - * - if REPE/REPZ and ZF = 0 then done - * - if REPNE/REPNZ and ZF = 1 then done - */ - if (((c->b == 0xa6) || (c->b == 0xa7) || - (c->b == 0xae) || (c->b == 0xaf)) - && (((c->rep_prefix == REPE_PREFIX) && - ((ctxt->eflags & EFLG_ZF) == 0)) - || ((c->rep_prefix == REPNE_PREFIX) && - ((ctxt->eflags & EFLG_ZF) == EFLG_ZF)))) + + if (string_insn_completed(ctxt)) ctxt->restart = false; /* * Re-enter guest when pio read ahead buffer is empty or, -- 2.20.1