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authorGleb Natapov <gleb@redhat.com>2012-12-20 16:57:43 +0200
committerMarcelo Tosatti <mtosatti@redhat.com>2013-01-02 19:36:27 -0200
commit045a282ca41505184e8fc805335d1f5aae0c8a03 (patch)
tree33f929ef73c595a69f71b9df8bb6f8c0b7ae86f1 /arch/x86/kvm/emulate.c
parent3a78a4f46302bfc83602a53dfa4dcbe76a7a1f5f (diff)
KVM: emulator: implement fninit, fnstsw, fnstcw
Signed-off-by: Gleb Natapov <gleb@redhat.com> Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
Diffstat (limited to 'arch/x86/kvm/emulate.c')
-rw-r--r--arch/x86/kvm/emulate.c126
1 files changed, 125 insertions, 1 deletions
diff --git a/arch/x86/kvm/emulate.c b/arch/x86/kvm/emulate.c
index a3d31e3d9875..53c5ad6851d1 100644
--- a/arch/x86/kvm/emulate.c
+++ b/arch/x86/kvm/emulate.c
@@ -115,6 +115,7 @@
#define GroupDual (2<<15) /* Alternate decoding of mod == 3 */
#define Prefix (3<<15) /* Instruction varies with 66/f2/f3 prefix */
#define RMExt (4<<15) /* Opcode extension in ModRM r/m if mod == 3 */
+#define Escape (5<<15) /* Escape to coprocessor instruction */
#define Sse (1<<18) /* SSE Vector instruction */
/* Generic ModRM decode. */
#define ModRM (1<<19)
@@ -166,6 +167,7 @@ struct opcode {
const struct opcode *group;
const struct group_dual *gdual;
const struct gprefix *gprefix;
+ const struct escape *esc;
} u;
int (*check_perm)(struct x86_emulate_ctxt *ctxt);
};
@@ -182,6 +184,11 @@ struct gprefix {
struct opcode pfx_f3;
};
+struct escape {
+ struct opcode op[8];
+ struct opcode high[64];
+};
+
/* EFLAGS bit definitions. */
#define EFLG_ID (1<<21)
#define EFLG_VIP (1<<20)
@@ -991,6 +998,53 @@ static void write_mmx_reg(struct x86_emulate_ctxt *ctxt, u64 *data, int reg)
ctxt->ops->put_fpu(ctxt);
}
+static int em_fninit(struct x86_emulate_ctxt *ctxt)
+{
+ if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
+ return emulate_nm(ctxt);
+
+ ctxt->ops->get_fpu(ctxt);
+ asm volatile("fninit");
+ ctxt->ops->put_fpu(ctxt);
+ return X86EMUL_CONTINUE;
+}
+
+static int em_fnstcw(struct x86_emulate_ctxt *ctxt)
+{
+ u16 fcw;
+
+ if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
+ return emulate_nm(ctxt);
+
+ ctxt->ops->get_fpu(ctxt);
+ asm volatile("fnstcw %0": "+m"(fcw));
+ ctxt->ops->put_fpu(ctxt);
+
+ /* force 2 byte destination */
+ ctxt->dst.bytes = 2;
+ ctxt->dst.val = fcw;
+
+ return X86EMUL_CONTINUE;
+}
+
+static int em_fnstsw(struct x86_emulate_ctxt *ctxt)
+{
+ u16 fsw;
+
+ if (ctxt->ops->get_cr(ctxt, 0) & (X86_CR0_TS | X86_CR0_EM))
+ return emulate_nm(ctxt);
+
+ ctxt->ops->get_fpu(ctxt);
+ asm volatile("fnstsw %0": "+m"(fsw));
+ ctxt->ops->put_fpu(ctxt);
+
+ /* force 2 byte destination */
+ ctxt->dst.bytes = 2;
+ ctxt->dst.val = fsw;
+
+ return X86EMUL_CONTINUE;
+}
+
static void decode_register_operand(struct x86_emulate_ctxt *ctxt,
struct operand *op)
{
@@ -3590,6 +3644,7 @@ static int check_perm_out(struct x86_emulate_ctxt *ctxt)
#define EXT(_f, _e) { .flags = ((_f) | RMExt), .u.group = (_e) }
#define G(_f, _g) { .flags = ((_f) | Group | ModRM), .u.group = (_g) }
#define GD(_f, _g) { .flags = ((_f) | GroupDual | ModRM), .u.gdual = (_g) }
+#define E(_f, _e) { .flags = ((_f) | Escape | ModRM), .u.esc = (_e) }
#define I(_f, _e) { .flags = (_f), .u.execute = (_e) }
#define II(_f, _e, _i) \
{ .flags = (_f), .u.execute = (_e), .intercept = x86_intercept_##_i }
@@ -3725,6 +3780,69 @@ static const struct gprefix pfx_vmovntpx = {
I(0, em_mov), N, N, N,
};
+static const struct escape escape_d9 = { {
+ N, N, N, N, N, N, N, I(DstMem, em_fnstcw),
+}, {
+ /* 0xC0 - 0xC7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xC8 - 0xCF */
+ N, N, N, N, N, N, N, N,
+ /* 0xD0 - 0xC7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xD8 - 0xDF */
+ N, N, N, N, N, N, N, N,
+ /* 0xE0 - 0xE7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xE8 - 0xEF */
+ N, N, N, N, N, N, N, N,
+ /* 0xF0 - 0xF7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xF8 - 0xFF */
+ N, N, N, N, N, N, N, N,
+} };
+
+static const struct escape escape_db = { {
+ N, N, N, N, N, N, N, N,
+}, {
+ /* 0xC0 - 0xC7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xC8 - 0xCF */
+ N, N, N, N, N, N, N, N,
+ /* 0xD0 - 0xC7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xD8 - 0xDF */
+ N, N, N, N, N, N, N, N,
+ /* 0xE0 - 0xE7 */
+ N, N, N, I(ImplicitOps, em_fninit), N, N, N, N,
+ /* 0xE8 - 0xEF */
+ N, N, N, N, N, N, N, N,
+ /* 0xF0 - 0xF7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xF8 - 0xFF */
+ N, N, N, N, N, N, N, N,
+} };
+
+static const struct escape escape_dd = { {
+ N, N, N, N, N, N, N, I(DstMem, em_fnstsw),
+}, {
+ /* 0xC0 - 0xC7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xC8 - 0xCF */
+ N, N, N, N, N, N, N, N,
+ /* 0xD0 - 0xC7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xD8 - 0xDF */
+ N, N, N, N, N, N, N, N,
+ /* 0xE0 - 0xE7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xE8 - 0xEF */
+ N, N, N, N, N, N, N, N,
+ /* 0xF0 - 0xF7 */
+ N, N, N, N, N, N, N, N,
+ /* 0xF8 - 0xFF */
+ N, N, N, N, N, N, N, N,
+} };
+
static const struct opcode opcode_table[256] = {
/* 0x00 - 0x07 */
I6ALU(Lock, em_add),
@@ -3821,7 +3939,7 @@ static const struct opcode opcode_table[256] = {
D2bv(DstMem | SrcOne | ModRM), D2bv(DstMem | ModRM),
N, I(DstAcc | SrcImmByte | No64, em_aad), N, N,
/* 0xD8 - 0xDF */
- N, N, N, N, N, N, N, N,
+ N, E(0, &escape_d9), N, E(0, &escape_db), N, E(0, &escape_dd), N, N,
/* 0xE0 - 0xE7 */
X3(I(SrcImmByte, em_loop)),
I(SrcImmByte, em_jcxz),
@@ -4246,6 +4364,12 @@ done_prefixes:
case 0xf3: opcode = opcode.u.gprefix->pfx_f3; break;
}
break;
+ case Escape:
+ if (ctxt->modrm > 0xbf)
+ opcode = opcode.u.esc->high[ctxt->modrm - 0xc0];
+ else
+ opcode = opcode.u.esc->op[(ctxt->modrm >> 3) & 7];
+ break;
default:
return EMULATION_FAILED;
}

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