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-rw-r--r--arch/x86/include/asm/insn.h231
1 files changed, 188 insertions, 43 deletions
diff --git a/arch/x86/include/asm/insn.h b/arch/x86/include/asm/insn.h
index 48eb30a86062..846d21c1a7f8 100644
--- a/arch/x86/include/asm/insn.h
+++ b/arch/x86/include/asm/insn.h
@@ -1,27 +1,17 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
#ifndef _ASM_X86_INSN_H
#define _ASM_X86_INSN_H
/*
* x86 instruction analysis
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
- *
- * You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
- *
* Copyright (C) IBM Corporation, 2009
*/
+#include <asm/byteorder.h>
/* insn_attr_t is defined in inat.h */
-#include <asm/inat.h>
+#include <asm/inat.h> /* __ignore_sync_check__ */
+
+#if defined(__BYTE_ORDER) ? __BYTE_ORDER == __LITTLE_ENDIAN : defined(__LITTLE_ENDIAN)
struct insn_field {
union {
@@ -33,13 +23,58 @@ struct insn_field {
unsigned char nbytes;
};
+static inline void insn_field_set(struct insn_field *p, insn_value_t v,
+ unsigned char n)
+{
+ p->value = v;
+ p->nbytes = n;
+}
+
+static inline void insn_set_byte(struct insn_field *p, unsigned char n,
+ insn_byte_t v)
+{
+ p->bytes[n] = v;
+}
+
+#else
+
+struct insn_field {
+ insn_value_t value;
+ union {
+ insn_value_t little;
+ insn_byte_t bytes[4];
+ };
+ /* !0 if we've run insn_get_xxx() for this field */
+ unsigned char got;
+ unsigned char nbytes;
+};
+
+static inline void insn_field_set(struct insn_field *p, insn_value_t v,
+ unsigned char n)
+{
+ p->value = v;
+ p->little = __cpu_to_le32(v);
+ p->nbytes = n;
+}
+
+static inline void insn_set_byte(struct insn_field *p, unsigned char n,
+ insn_byte_t v)
+{
+ p->bytes[n] = v;
+ p->value = __le32_to_cpu(p->little);
+}
+#endif
+
struct insn {
struct insn_field prefixes; /*
* Prefixes
* prefixes.bytes[3]: last prefix
*/
struct insn_field rex_prefix; /* REX prefix */
- struct insn_field vex_prefix; /* VEX prefix */
+ union {
+ struct insn_field vex_prefix; /* VEX prefix */
+ struct insn_field xop_prefix; /* XOP prefix */
+ };
struct insn_field opcode; /*
* opcode.bytes[0]: opcode1
* opcode.bytes[1]: opcode2
@@ -58,6 +93,7 @@ struct insn {
struct insn_field immediate2; /* for 64bit imm or seg16 */
};
+ int emulate_prefix_size;
insn_attr_t attr;
unsigned char opnd_bytes;
unsigned char addr_bytes;
@@ -65,10 +101,11 @@ struct insn {
unsigned char x86_64;
const insn_byte_t *kaddr; /* kernel address of insn to analyze */
+ const insn_byte_t *end_kaddr; /* kernel address of last insn in buffer */
const insn_byte_t *next_byte;
};
-#define MAX_INSN_SIZE 16
+#define MAX_INSN_SIZE 15
#define X86_MODRM_MOD(modrm) (((modrm) & 0xc0) >> 6)
#define X86_MODRM_REG(modrm) (((modrm) & 0x38) >> 3)
@@ -78,10 +115,15 @@ struct insn {
#define X86_SIB_INDEX(sib) (((sib) & 0x38) >> 3)
#define X86_SIB_BASE(sib) ((sib) & 0x07)
-#define X86_REX_W(rex) ((rex) & 8)
-#define X86_REX_R(rex) ((rex) & 4)
-#define X86_REX_X(rex) ((rex) & 2)
-#define X86_REX_B(rex) ((rex) & 1)
+#define X86_REX2_M(rex) ((rex) & 0x80) /* REX2 M0 */
+#define X86_REX2_R(rex) ((rex) & 0x40) /* REX2 R4 */
+#define X86_REX2_X(rex) ((rex) & 0x20) /* REX2 X4 */
+#define X86_REX2_B(rex) ((rex) & 0x10) /* REX2 B4 */
+
+#define X86_REX_W(rex) ((rex) & 8) /* REX or REX2 W */
+#define X86_REX_R(rex) ((rex) & 4) /* REX or REX2 R3 */
+#define X86_REX_X(rex) ((rex) & 2) /* REX or REX2 X3 */
+#define X86_REX_B(rex) ((rex) & 1) /* REX or REX2 B3 */
/* VEX bit flags */
#define X86_VEX_W(vex) ((vex) & 0x80) /* VEX3 Byte2 */
@@ -90,20 +132,44 @@ struct insn {
#define X86_VEX_B(vex) ((vex) & 0x20) /* VEX3 Byte1 */
#define X86_VEX_L(vex) ((vex) & 0x04) /* VEX3 Byte2, VEX2 Byte1 */
/* VEX bit fields */
+#define X86_EVEX_M(vex) ((vex) & 0x07) /* EVEX Byte1 */
#define X86_VEX3_M(vex) ((vex) & 0x1f) /* VEX3 Byte1 */
#define X86_VEX2_M 1 /* VEX2.M always 1 */
#define X86_VEX_V(vex) (((vex) & 0x78) >> 3) /* VEX3 Byte2, VEX2 Byte1 */
#define X86_VEX_P(vex) ((vex) & 0x03) /* VEX3 Byte2, VEX2 Byte1 */
#define X86_VEX_M_MAX 0x1f /* VEX3.M Maximum value */
+/* XOP bit fields */
+#define X86_XOP_R(xop) ((xop) & 0x80) /* XOP Byte2 */
+#define X86_XOP_X(xop) ((xop) & 0x40) /* XOP Byte2 */
+#define X86_XOP_B(xop) ((xop) & 0x20) /* XOP Byte2 */
+#define X86_XOP_M(xop) ((xop) & 0x1f) /* XOP Byte2 */
+#define X86_XOP_W(xop) ((xop) & 0x80) /* XOP Byte3 */
+#define X86_XOP_V(xop) ((xop) & 0x78) /* XOP Byte3 */
+#define X86_XOP_L(xop) ((xop) & 0x04) /* XOP Byte3 */
+#define X86_XOP_P(xop) ((xop) & 0x03) /* XOP Byte3 */
+#define X86_XOP_M_MIN 0x08 /* Min of XOP.M */
+#define X86_XOP_M_MAX 0x1f /* Max of XOP.M */
-extern void insn_init(struct insn *insn, const void *kaddr, int x86_64);
-extern void insn_get_prefixes(struct insn *insn);
-extern void insn_get_opcode(struct insn *insn);
-extern void insn_get_modrm(struct insn *insn);
-extern void insn_get_sib(struct insn *insn);
-extern void insn_get_displacement(struct insn *insn);
-extern void insn_get_immediate(struct insn *insn);
-extern void insn_get_length(struct insn *insn);
+extern void insn_init(struct insn *insn, const void *kaddr, int buf_len, int x86_64);
+extern int insn_get_prefixes(struct insn *insn);
+extern int insn_get_opcode(struct insn *insn);
+extern int insn_get_modrm(struct insn *insn);
+extern int insn_get_sib(struct insn *insn);
+extern int insn_get_displacement(struct insn *insn);
+extern int insn_get_immediate(struct insn *insn);
+extern int insn_get_length(struct insn *insn);
+
+enum insn_mode {
+ INSN_MODE_32,
+ INSN_MODE_64,
+ /* Mode is determined by the current kernel build. */
+ INSN_MODE_KERN,
+ INSN_NUM_MODES,
+};
+
+extern int insn_decode(struct insn *insn, const void *kaddr, int buf_len, enum insn_mode m);
+
+#define insn_decode_kernel(_insn, _ptr) insn_decode((_insn), (_ptr), MAX_INSN_SIZE, INSN_MODE_KERN)
/* Attribute will be determined after getting ModRM (for opcode groups) */
static inline void insn_get_attribute(struct insn *insn)
@@ -114,36 +180,61 @@ static inline void insn_get_attribute(struct insn *insn)
/* Instruction uses RIP-relative addressing */
extern int insn_rip_relative(struct insn *insn);
-/* Init insn for kernel text */
-static inline void kernel_insn_init(struct insn *insn, const void *kaddr)
+static inline int insn_is_rex2(struct insn *insn)
{
-#ifdef CONFIG_X86_64
- insn_init(insn, kaddr, 1);
-#else /* CONFIG_X86_32 */
- insn_init(insn, kaddr, 0);
-#endif
+ if (!insn->prefixes.got)
+ insn_get_prefixes(insn);
+ return insn->rex_prefix.nbytes == 2;
}
-static inline int insn_is_avx(struct insn *insn)
+static inline insn_byte_t insn_rex2_m_bit(struct insn *insn)
+{
+ return X86_REX2_M(insn->rex_prefix.bytes[1]);
+}
+
+static inline int insn_is_avx_or_xop(struct insn *insn)
{
if (!insn->prefixes.got)
insn_get_prefixes(insn);
return (insn->vex_prefix.value != 0);
}
-/* Ensure this instruction is decoded completely */
-static inline int insn_complete(struct insn *insn)
+static inline int insn_is_evex(struct insn *insn)
+{
+ if (!insn->prefixes.got)
+ insn_get_prefixes(insn);
+ return (insn->vex_prefix.nbytes == 4);
+}
+
+/* If we already know this is AVX/XOP encoded */
+static inline int avx_insn_is_xop(struct insn *insn)
{
- return insn->opcode.got && insn->modrm.got && insn->sib.got &&
- insn->displacement.got && insn->immediate.got;
+ insn_attr_t attr = inat_get_opcode_attribute(insn->vex_prefix.bytes[0]);
+
+ return inat_is_xop_prefix(attr);
+}
+
+static inline int insn_is_xop(struct insn *insn)
+{
+ if (!insn_is_avx_or_xop(insn))
+ return 0;
+
+ return avx_insn_is_xop(insn);
+}
+
+static inline int insn_has_emulate_prefix(struct insn *insn)
+{
+ return !!insn->emulate_prefix_size;
}
static inline insn_byte_t insn_vex_m_bits(struct insn *insn)
{
if (insn->vex_prefix.nbytes == 2) /* 2 bytes VEX */
return X86_VEX2_M;
- else
+ else if (insn->vex_prefix.nbytes == 3) /* 3 bytes VEX */
return X86_VEX3_M(insn->vex_prefix.bytes[1]);
+ else /* EVEX */
+ return X86_EVEX_M(insn->vex_prefix.bytes[1]);
}
static inline insn_byte_t insn_vex_p_bits(struct insn *insn)
@@ -154,11 +245,33 @@ static inline insn_byte_t insn_vex_p_bits(struct insn *insn)
return X86_VEX_P(insn->vex_prefix.bytes[2]);
}
+static inline insn_byte_t insn_vex_w_bit(struct insn *insn)
+{
+ if (insn->vex_prefix.nbytes < 3)
+ return 0;
+ return X86_VEX_W(insn->vex_prefix.bytes[2]);
+}
+
+static inline insn_byte_t insn_xop_map_bits(struct insn *insn)
+{
+ if (insn->xop_prefix.nbytes < 3) /* XOP is 3 bytes */
+ return 0;
+ return X86_XOP_M(insn->xop_prefix.bytes[1]);
+}
+
+static inline insn_byte_t insn_xop_p_bits(struct insn *insn)
+{
+ return X86_XOP_P(insn->vex_prefix.bytes[2]);
+}
+
/* Get the last prefix id from last prefix or VEX prefix */
static inline int insn_last_prefix_id(struct insn *insn)
{
- if (insn_is_avx(insn))
+ if (insn_is_avx_or_xop(insn)) {
+ if (avx_insn_is_xop(insn))
+ return insn_xop_p_bits(insn);
return insn_vex_p_bits(insn); /* VEX_p is a SIMD prefix id */
+ }
if (insn->prefixes.bytes[3])
return inat_get_last_prefix_id(insn->prefixes.bytes[3]);
@@ -196,4 +309,36 @@ static inline int insn_offset_immediate(struct insn *insn)
return insn_offset_displacement(insn) + insn->displacement.nbytes;
}
+/**
+ * for_each_insn_prefix() -- Iterate prefixes in the instruction
+ * @insn: Pointer to struct insn.
+ * @prefix: Prefix byte.
+ *
+ * Iterate prefix bytes of given @insn. Each prefix byte is stored in @prefix
+ * and the index is stored in @idx (note that this @idx is just for a cursor,
+ * do not change it.)
+ * Since prefixes.nbytes can be bigger than 4 if some prefixes
+ * are repeated, it cannot be used for looping over the prefixes.
+ */
+#define for_each_insn_prefix(insn, prefix) \
+ for (int idx = 0; idx < ARRAY_SIZE(insn->prefixes.bytes) && (prefix = insn->prefixes.bytes[idx]) != 0; idx++)
+
+#define POP_SS_OPCODE 0x1f
+#define MOV_SREG_OPCODE 0x8e
+
+/*
+ * Intel SDM Vol.3A 6.8.3 states;
+ * "Any single-step trap that would be delivered following the MOV to SS
+ * instruction or POP to SS instruction (because EFLAGS.TF is 1) is
+ * suppressed."
+ * This function returns true if @insn is MOV SS or POP SS. On these
+ * instructions, single stepping is suppressed.
+ */
+static inline int insn_masking_exception(struct insn *insn)
+{
+ return insn->opcode.bytes[0] == POP_SS_OPCODE ||
+ (insn->opcode.bytes[0] == MOV_SREG_OPCODE &&
+ X86_MODRM_REG(insn->modrm.bytes[0]) == 2);
+}
+
#endif /* _ASM_X86_INSN_H */
generated by cgit (git 2.34.1) at 2025-12-25 08:02:03 +0000