From bbe9abbdaca366510db1f2df25f4c7b48cba38eb Mon Sep 17 00:00:00 2001 From: Nitin A Kamble Date: Sat, 15 Sep 2007 10:23:07 +0300 Subject: [PATCH] KVM: x86 emulator: imlpement jump conditional relative Implement emulation of instruction: jump conditional rel opcodes: 0x0f 0x80 - 0x0f 0x8f Signed-off-by: Nitin A Kamble Signed-off-by: Avi Kivity --- drivers/kvm/x86_emulate.c | 61 ++++++++++++++++++++++++++++++++++++++- 1 file changed, 60 insertions(+), 1 deletion(-) diff --git a/drivers/kvm/x86_emulate.c b/drivers/kvm/x86_emulate.c index e4ce34c52ba1..ba53e59f558a 100644 --- a/drivers/kvm/x86_emulate.c +++ b/drivers/kvm/x86_emulate.c @@ -188,7 +188,10 @@ static u16 twobyte_table[256] = { /* 0x70 - 0x7F */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x80 - 0x8F */ - 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, + ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps, + ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps, + ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps, + ImplicitOps, ImplicitOps, ImplicitOps, ImplicitOps, /* 0x90 - 0x9F */ 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0xA0 - 0xA7 */ @@ -479,6 +482,41 @@ static int read_descriptor(struct x86_emulate_ctxt *ctxt, return rc; } +static int test_cc(unsigned int condition, unsigned int flags) +{ + int rc = 0; + + switch ((condition & 15) >> 1) { + case 0: /* o */ + rc |= (flags & EFLG_OF); + break; + case 1: /* b/c/nae */ + rc |= (flags & EFLG_CF); + break; + case 2: /* z/e */ + rc |= (flags & EFLG_ZF); + break; + case 3: /* be/na */ + rc |= (flags & (EFLG_CF|EFLG_ZF)); + break; + case 4: /* s */ + rc |= (flags & EFLG_SF); + break; + case 5: /* p/pe */ + rc |= (flags & EFLG_PF); + break; + case 7: /* le/ng */ + rc |= (flags & EFLG_ZF); + /* fall through */ + case 6: /* l/nge */ + rc |= (!(flags & EFLG_SF) != !(flags & EFLG_OF)); + break; + } + + /* Odd condition identifiers (lsb == 1) have inverted sense. */ + return (!!rc ^ (condition & 1)); +} + int x86_emulate_memop(struct x86_emulate_ctxt *ctxt, struct x86_emulate_ops *ops) { @@ -1486,6 +1524,27 @@ twobyte_special_insn: } rc = X86EMUL_CONTINUE; break; + case 0x80 ... 0x8f: /* jnz rel, etc*/ { + long int rel; + + switch (op_bytes) { + case 2: + rel = insn_fetch(s16, 2, _eip); + break; + case 4: + rel = insn_fetch(s32, 4, _eip); + break; + case 8: + rel = insn_fetch(s64, 8, _eip); + break; + default: + DPRINTF("jnz: Invalid op_bytes\n"); + goto cannot_emulate; + } + if (test_cc(b, _eflags)) + JMP_REL(rel); + break; + } case 0xc7: /* Grp9 (cmpxchg8b) */ { u64 old, new; -- 2.39.5