x86/insn: Avoid namespace clash by separating instruction decoder MMIO type from MMIO trace type

Both <linux/mmiotrace.h> and <asm/insn-eval.h> define various MMIO_ enum constants,
whose namespace overlaps.

Rename the <asm/insn-eval.h> ones to have a INSN_ prefix, so that the headers can be
used from the same source file.

Signed-off-by: Jason A. Donenfeld <[e-mail]>
Signed-off-by: Ingo Molnar <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

arch/x86/coco/tdx/tdx.c

···
 {
 	unsigned long *reg, val, vaddr;
 	char buffer[MAX_INSN_SIZE];
+	enum insn_mmio_type mmio;
 	struct insn insn = {};
-	enum mmio_type mmio;
 	int size, extend_size;
 	u8 extend_val = 0;
 
···
 		return -EINVAL;
 
 	mmio = insn_decode_mmio(&insn, &size);
-	if (WARN_ON_ONCE(mmio == MMIO_DECODE_FAILED))
+	if (WARN_ON_ONCE(mmio == INSN_MMIO_DECODE_FAILED))
 		return -EINVAL;
 
-	if (mmio != MMIO_WRITE_IMM && mmio != MMIO_MOVS) {
+	if (mmio != INSN_MMIO_WRITE_IMM && mmio != INSN_MMIO_MOVS) {
 		reg = insn_get_modrm_reg_ptr(&insn, regs);
 		if (!reg)
 			return -EINVAL;
···
 
 	/* Handle writes first */
 	switch (mmio) {
-	case MMIO_WRITE:
+	case INSN_MMIO_WRITE:
 		memcpy(&val, reg, size);
 		if (!mmio_write(size, ve->gpa, val))
 			return -EIO;
 		return insn.length;
-	case MMIO_WRITE_IMM:
+	case INSN_MMIO_WRITE_IMM:
 		val = insn.immediate.value;
 		if (!mmio_write(size, ve->gpa, val))
 			return -EIO;
 		return insn.length;
-	case MMIO_READ:
-	case MMIO_READ_ZERO_EXTEND:
-	case MMIO_READ_SIGN_EXTEND:
+	case INSN_MMIO_READ:
+	case INSN_MMIO_READ_ZERO_EXTEND:
+	case INSN_MMIO_READ_SIGN_EXTEND:
 		/* Reads are handled below */
 		break;
-	case MMIO_MOVS:
-	case MMIO_DECODE_FAILED:
+	case INSN_MMIO_MOVS:
+	case INSN_MMIO_DECODE_FAILED:
 		/*
 		 * MMIO was accessed with an instruction that could not be
 		 * decoded or handled properly. It was likely not using io.h
···
 		return -EIO;
 
 	switch (mmio) {
-	case MMIO_READ:
+	case INSN_MMIO_READ:
 		/* Zero-extend for 32-bit operation */
 		extend_size = size == 4 ? sizeof(*reg) : 0;
 		break;
-	case MMIO_READ_ZERO_EXTEND:
+	case INSN_MMIO_READ_ZERO_EXTEND:
 		/* Zero extend based on operand size */
 		extend_size = insn.opnd_bytes;
 		break;
-	case MMIO_READ_SIGN_EXTEND:
+	case INSN_MMIO_READ_SIGN_EXTEND:
 		/* Sign extend based on operand size */
 		extend_size = insn.opnd_bytes;
 		if (size == 1 && val & BIT(7))

arch/x86/include/asm/insn-eval.h

···
 bool insn_decode_from_regs(struct insn *insn, struct pt_regs *regs,
 			   unsigned char buf[MAX_INSN_SIZE], int buf_size);
 
-enum mmio_type {
-	MMIO_DECODE_FAILED,
-	MMIO_WRITE,
-	MMIO_WRITE_IMM,
-	MMIO_READ,
-	MMIO_READ_ZERO_EXTEND,
-	MMIO_READ_SIGN_EXTEND,
-	MMIO_MOVS,
+enum insn_mmio_type {
+	INSN_MMIO_DECODE_FAILED,
+	INSN_MMIO_WRITE,
+	INSN_MMIO_WRITE_IMM,
+	INSN_MMIO_READ,
+	INSN_MMIO_READ_ZERO_EXTEND,
+	INSN_MMIO_READ_SIGN_EXTEND,
+	INSN_MMIO_MOVS,
 };
 
-enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes);
+enum insn_mmio_type insn_decode_mmio(struct insn *insn, int *bytes);
 
 #endif /* _ASM_X86_INSN_EVAL_H */

arch/x86/kernel/sev.c

···
 static enum es_result vc_handle_mmio(struct ghcb *ghcb, struct es_em_ctxt *ctxt)
 {
 	struct insn *insn = &ctxt->insn;
+	enum insn_mmio_type mmio;
 	unsigned int bytes = 0;
-	enum mmio_type mmio;
 	enum es_result ret;
 	u8 sign_byte;
 	long *reg_data;
 
 	mmio = insn_decode_mmio(insn, &bytes);
-	if (mmio == MMIO_DECODE_FAILED)
+	if (mmio == INSN_MMIO_DECODE_FAILED)
 		return ES_DECODE_FAILED;
 
-	if (mmio != MMIO_WRITE_IMM && mmio != MMIO_MOVS) {
+	if (mmio != INSN_MMIO_WRITE_IMM && mmio != INSN_MMIO_MOVS) {
 		reg_data = insn_get_modrm_reg_ptr(insn, ctxt->regs);
 		if (!reg_data)
 			return ES_DECODE_FAILED;
 	}
 
 	switch (mmio) {
-	case MMIO_WRITE:
+	case INSN_MMIO_WRITE:
 		memcpy(ghcb->shared_buffer, reg_data, bytes);
 		ret = vc_do_mmio(ghcb, ctxt, bytes, false);
 		break;
-	case MMIO_WRITE_IMM:
+	case INSN_MMIO_WRITE_IMM:
 		memcpy(ghcb->shared_buffer, insn->immediate1.bytes, bytes);
 		ret = vc_do_mmio(ghcb, ctxt, bytes, false);
 		break;
-	case MMIO_READ:
+	case INSN_MMIO_READ:
 		ret = vc_do_mmio(ghcb, ctxt, bytes, true);
 		if (ret)
 			break;
···
 
 		memcpy(reg_data, ghcb->shared_buffer, bytes);
 		break;
-	case MMIO_READ_ZERO_EXTEND:
+	case INSN_MMIO_READ_ZERO_EXTEND:
 		ret = vc_do_mmio(ghcb, ctxt, bytes, true);
 		if (ret)
 			break;
···
 		memset(reg_data, 0, insn->opnd_bytes);
 		memcpy(reg_data, ghcb->shared_buffer, bytes);
 		break;
-	case MMIO_READ_SIGN_EXTEND:
+	case INSN_MMIO_READ_SIGN_EXTEND:
 		ret = vc_do_mmio(ghcb, ctxt, bytes, true);
 		if (ret)
 			break;
···
 		memset(reg_data, sign_byte, insn->opnd_bytes);
 		memcpy(reg_data, ghcb->shared_buffer, bytes);
 		break;
-	case MMIO_MOVS:
+	case INSN_MMIO_MOVS:
 		ret = vc_handle_mmio_movs(ctxt, bytes);
 		break;
 	default:

arch/x86/lib/insn-eval.c

···
  * Returns:
  *
  * Type of the instruction. Size of the memory operand is stored in
- * @bytes. If decode failed, MMIO_DECODE_FAILED returned.
+ * @bytes. If decode failed, INSN_MMIO_DECODE_FAILED returned.
  */
-enum mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
+enum insn_mmio_type insn_decode_mmio(struct insn *insn, int *bytes)
 {
-	enum mmio_type type = MMIO_DECODE_FAILED;
+	enum insn_mmio_type type = INSN_MMIO_DECODE_FAILED;
 
 	*bytes = 0;
 
 	if (insn_get_opcode(insn))
-		return MMIO_DECODE_FAILED;
+		return INSN_MMIO_DECODE_FAILED;
 
 	switch (insn->opcode.bytes[0]) {
 	case 0x88: /* MOV m8,r8 */
···
 	case 0x89: /* MOV m16/m32/m64, r16/m32/m64 */
 		if (!*bytes)
 			*bytes = insn->opnd_bytes;
-		type = MMIO_WRITE;
+		type = INSN_MMIO_WRITE;
 		break;
 
 	case 0xc6: /* MOV m8, imm8 */
···
 	case 0xc7: /* MOV m16/m32/m64, imm16/imm32/imm64 */
 		if (!*bytes)
 			*bytes = insn->opnd_bytes;
-		type = MMIO_WRITE_IMM;
+		type = INSN_MMIO_WRITE_IMM;
 		break;
 
 	case 0x8a: /* MOV r8, m8 */
···
 	case 0x8b: /* MOV r16/r32/r64, m16/m32/m64 */
 		if (!*bytes)
 			*bytes = insn->opnd_bytes;
-		type = MMIO_READ;
+		type = INSN_MMIO_READ;
 		break;
 
 	case 0xa4: /* MOVS m8, m8 */
···
 	case 0xa5: /* MOVS m16/m32/m64, m16/m32/m64 */
 		if (!*bytes)
 			*bytes = insn->opnd_bytes;
-		type = MMIO_MOVS;
+		type = INSN_MMIO_MOVS;
 		break;
 
 	case 0x0f: /* Two-byte instruction */
···
 		case 0xb7: /* MOVZX r32/r64, m16 */
 			if (!*bytes)
 				*bytes = 2;
-			type = MMIO_READ_ZERO_EXTEND;
+			type = INSN_MMIO_READ_ZERO_EXTEND;
 			break;
 
 		case 0xbe: /* MOVSX r16/r32/r64, m8 */
···
 		case 0xbf: /* MOVSX r32/r64, m16 */
 			if (!*bytes)
 				*bytes = 2;
-			type = MMIO_READ_SIGN_EXTEND;
+			type = INSN_MMIO_READ_SIGN_EXTEND;
 			break;
 		}
 		break;