Subject: [PATCH v7 3/7] arm64: move encode_insn_immediate() from module.c to insn.c

From: [email-masked] (Jiang Liu)
Date: Sun, 22 Dec 2013 23:25:39 +0800

Function encode_insn_immediate() will be used by other instruction
manipulate related functions, so move it into insn.c and rename it
as aarch64_insn_encode_immediate().

Reviewed-by: Will Deacon <[email-masked]>
Signed-off-by: Jiang Liu <[email-masked]>
---
 arch/arm64/include/asm/insn.h |  13 ++++
 arch/arm64/kernel/insn.c      |  54 +++++++++++++++
 arch/arm64/kernel/module.c    | 157 +++++++++++++-----------------------------
 3 files changed, 114 insertions(+), 110 deletions(-)

diff --git a/arch/arm64/include/asm/insn.h b/arch/arm64/include/asm/insn.h
index bf8085f..fb44660 100644
--- a/arch/arm64/include/asm/insn.h
+++ b/arch/arm64/include/asm/insn.h
@@ -55,6 +55,17 @@ enum aarch64_insn_hint_op {
 	AARCH64_INSN_HINT_SEVL	= 0x5 << 5,
 };
 
+enum aarch64_insn_imm_type {
+	AARCH64_INSN_IMM_ADR,
+	AARCH64_INSN_IMM_26,
+	AARCH64_INSN_IMM_19,
+	AARCH64_INSN_IMM_16,
+	AARCH64_INSN_IMM_14,
+	AARCH64_INSN_IMM_12,
+	AARCH64_INSN_IMM_9,
+	AARCH64_INSN_IMM_MAX
+};
+
 #define	__AARCH64_INSN_FUNCS(abbr, mask, val)	\
 static __always_inline bool aarch64_insn_is_##abbr(u32 code) \
 { return (code & (mask)) == (val); } \
@@ -76,6 +87,8 @@ bool aarch64_insn_is_nop(u32 insn);
 int aarch64_insn_read(void *addr, u32 *insnp);
 int aarch64_insn_write(void *addr, u32 insn);
 enum aarch64_insn_encoding_class aarch64_get_insn_class(u32 insn);
+u32 aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type,
+				  u32 insn, u64 imm);
 bool aarch64_insn_hotpatch_safe(u32 old_insn, u32 new_insn);
 
 int aarch64_insn_patch_text_nosync(void *addr, u32 insn);
diff --git a/arch/arm64/kernel/insn.c b/arch/arm64/kernel/insn.c
index b9dac57..7df0807 100644
--- a/arch/arm64/kernel/insn.c
+++ b/arch/arm64/kernel/insn.c
@@ -208,3 +208,57 @@ int __kprobes aarch64_insn_patch_text(void *addrs[], u32 insns[], int cnt)
 
 	return aarch64_insn_patch_text_sync(addrs, insns, cnt);
 }
+
+u32 __kprobes aarch64_insn_encode_immediate(enum aarch64_insn_imm_type type,
+				  u32 insn, u64 imm)
+{
+	u32 immlo, immhi, lomask, himask, mask;
+	int shift;
+
+	switch (type) {
+	case AARCH64_INSN_IMM_ADR:
+		lomask = 0x3;
+		himask = 0x7ffff;
+		immlo = imm & lomask;
+		imm >>= 2;
+		immhi = imm & himask;
+		imm = (immlo << 24) | (immhi);
+		mask = (lomask << 24) | (himask);
+		shift = 5;
+		break;
+	case AARCH64_INSN_IMM_26:
+		mask = BIT(26) - 1;
+		shift = 0;
+		break;
+	case AARCH64_INSN_IMM_19:
+		mask = BIT(19) - 1;
+		shift = 5;
+		break;
+	case AARCH64_INSN_IMM_16:
+		mask = BIT(16) - 1;
+		shift = 5;
+		break;
+	case AARCH64_INSN_IMM_14:
+		mask = BIT(14) - 1;
+		shift = 5;
+		break;
+	case AARCH64_INSN_IMM_12:
+		mask = BIT(12) - 1;
+		shift = 10;
+		break;
+	case AARCH64_INSN_IMM_9:
+		mask = BIT(9) - 1;
+		shift = 12;
+		break;
+	default:
+		pr_err("aarch64_insn_encode_immediate: unknown immediate encoding %d\n",
+			type);
+		return 0;
+	}
+
+	/* Update the immediate field. */
+	insn &= ~(mask << shift);
+	insn |= (imm & mask) << shift;
+
+	return insn;
+}
diff --git a/arch/arm64/kernel/module.c b/arch/arm64/kernel/module.c
index e2ad0d8..1eb1cc9 100644
--- a/arch/arm64/kernel/module.c
+++ b/arch/arm64/kernel/module.c
@@ -25,6 +25,10 @@
 #include <linux/mm.h>
 #include <linux/moduleloader.h>
 #include <linux/vmalloc.h>
+#include <asm/insn.h>
+
+#define	AARCH64_INSN_IMM_MOVNZ		AARCH64_INSN_IMM_MAX
+#define	AARCH64_INSN_IMM_MOVK		AARCH64_INSN_IMM_16
 
 void *module_alloc(unsigned long size)
 {
@@ -94,28 +98,18 @@ static int reloc_data(enum aarch64_reloc_op op, void *place, u64 val, int len)
 	return 0;
 }
 
-enum aarch64_imm_type {
-	INSN_IMM_MOVNZ,
-	INSN_IMM_MOVK,
-	INSN_IMM_ADR,
-	INSN_IMM_26,
-	INSN_IMM_19,
-	INSN_IMM_16,
-	INSN_IMM_14,
-	INSN_IMM_12,
-	INSN_IMM_9,
-};
-
-static u32 encode_insn_immediate(enum aarch64_imm_type type, u32 insn, u64 imm)
+static int reloc_insn_movw(enum aarch64_reloc_op op, void *place, u64 val,
+			   int lsb, enum aarch64_insn_imm_type imm_type)
 {
-	u32 immlo, immhi, lomask, himask, mask;
-	int shift;
+	u64 imm, limit = 0;
+	s64 sval;
+	u32 insn = le32_to_cpu(*(u32 *)place);
 
-	/* The instruction stream is always little endian. */
-	insn = le32_to_cpu(insn);
+	sval = do_reloc(op, place, val);
+	sval >>= lsb;
+	imm = sval & 0xffff;
 
-	switch (type) {
-	case INSN_IMM_MOVNZ:
+	if (imm_type == AARCH64_INSN_IMM_MOVNZ) {
 		/*
 		 * For signed MOVW relocations, we have to manipulate the
 		 * instruction encoding depending on whether or not the
@@ -134,70 +128,12 @@ static u32 encode_insn_immediate(enum aarch64_imm_type type, u32 insn, u64 imm)
 			 */
 			imm = ~imm;
 		}
-	case INSN_IMM_MOVK:
-		mask = BIT(16) - 1;
-		shift = 5;
-		break;
-	case INSN_IMM_ADR:
-		lomask = 0x3;
-		himask = 0x7ffff;
-		immlo = imm & lomask;
-		imm >>= 2;
-		immhi = imm & himask;
-		imm = (immlo << 24) | (immhi);
-		mask = (lomask << 24) | (himask);
-		shift = 5;
-		break;
-	case INSN_IMM_26:
-		mask = BIT(26) - 1;
-		shift = 0;
-		break;
-	case INSN_IMM_19:
-		mask = BIT(19) - 1;
-		shift = 5;
-		break;
-	case INSN_IMM_16:
-		mask = BIT(16) - 1;
-		shift = 5;
-		break;
-	case INSN_IMM_14:
-		mask = BIT(14) - 1;
-		shift = 5;
-		break;
-	case INSN_IMM_12:
-		mask = BIT(12) - 1;
-		shift = 10;
-		break;
-	case INSN_IMM_9:
-		mask = BIT(9) - 1;
-		shift = 12;
-		break;
-	default:
-		pr_err("encode_insn_immediate: unknown immediate encoding %d\n",
-			type);
-		return 0;
+		imm_type = AARCH64_INSN_IMM_MOVK;
 	}
 
-	/* Update the immediate field. */
-	insn &= ~(mask << shift);
-	insn |= (imm & mask) << shift;
-
-	return cpu_to_le32(insn);
-}
-
-static int reloc_insn_movw(enum aarch64_reloc_op op, void *place, u64 val,
-			   int lsb, enum aarch64_imm_type imm_type)
-{
-	u64 imm, limit = 0;
-	s64 sval;
-	u32 insn = *(u32 *)place;
-
-	sval = do_reloc(op, place, val);
-	sval >>= lsb;
-	imm = sval & 0xffff;
-
 	/* Update the instruction with the new encoding. */
-	*(u32 *)place = encode_insn_immediate(imm_type, insn, imm);
+	insn = aarch64_insn_encode_immediate(imm_type, insn, imm);
+	*(u32 *)place = cpu_to_le32(insn);
 
 	/* Shift out the immediate field. */
 	sval >>= 16;
@@ -206,9 +142,9 @@ static int reloc_insn_movw(enum aarch64_reloc_op op, void *place, u64 val,
 	 * For unsigned immediates, the overflow check is straightforward.
 	 * For signed immediates, the sign bit is actually the bit past the
 	 * most significant bit of the field.
-	 * The INSN_IMM_16 immediate type is unsigned.
+	 * The AARCH64_INSN_IMM_16 immediate type is unsigned.
 	 */
-	if (imm_type != INSN_IMM_16) {
+	if (imm_type != AARCH64_INSN_IMM_16) {
 		sval++;
 		limit++;
 	}
@@ -221,11 +157,11 @@ static int reloc_insn_movw(enum aarch64_reloc_op op, void *place, u64 val,
 }
 
 static int reloc_insn_imm(enum aarch64_reloc_op op, void *place, u64 val,
-			  int lsb, int len, enum aarch64_imm_type imm_type)
+			  int lsb, int len, enum aarch64_insn_imm_type imm_type)
 {
 	u64 imm, imm_mask;
 	s64 sval;
-	u32 insn = *(u32 *)place;
+	u32 insn = le32_to_cpu(*(u32 *)place);
 
 	/* Calculate the relocation value. */
 	sval = do_reloc(op, place, val);
@@ -236,7 +172,8 @@ static int reloc_insn_imm(enum aarch64_reloc_op op, void *place, u64 val,
 	imm = sval & imm_mask;
 
 	/* Update the instruction's immediate field. */
-	*(u32 *)place = encode_insn_immediate(imm_type, insn, imm);
+	insn = aarch64_insn_encode_immediate(imm_type, insn, imm);
+	*(u32 *)place = cpu_to_le32(insn);
 
 	/*
 	 * Extract the upper value bits (including the sign bit) and
@@ -318,125 +255,125 @@ int apply_relocate_add(Elf64_Shdr *sechdrs,
 			overflow_check = false;
 		case R_AARCH64_MOVW_UABS_G0:
 			ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 0,
-					      INSN_IMM_16);
+					      AARCH64_INSN_IMM_16);
 			break;
 		case R_AARCH64_MOVW_UABS_G1_NC:
 			overflow_check = false;
 		case R_AARCH64_MOVW_UABS_G1:
 			ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 16,
-					      INSN_IMM_16);
+					      AARCH64_INSN_IMM_16);
 			break;
 		case R_AARCH64_MOVW_UABS_G2_NC:
 			overflow_check = false;
 		case R_AARCH64_MOVW_UABS_G2:
 			ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 32,
-					      INSN_IMM_16);
+					      AARCH64_INSN_IMM_16);
 			break;
 		case R_AARCH64_MOVW_UABS_G3:
 			/* We're using the top bits so we can't overflow. */
 			overflow_check = false;
 			ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 48,
-					      INSN_IMM_16);
+					      AARCH64_INSN_IMM_16);
 			break;
 		case R_AARCH64_MOVW_SABS_G0:
 			ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 0,
-					      INSN_IMM_MOVNZ);
+					      AARCH64_INSN_IMM_MOVNZ);
 			break;
 		case R_AARCH64_MOVW_SABS_G1:
 			ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 16,
-					      INSN_IMM_MOVNZ);
+					      AARCH64_INSN_IMM_MOVNZ);
 			break;
 		case R_AARCH64_MOVW_SABS_G2:
 			ovf = reloc_insn_movw(RELOC_OP_ABS, loc, val, 32,
-					      INSN_IMM_MOVNZ);
+					      AARCH64_INSN_IMM_MOVNZ);
 			break;
 		case R_AARCH64_MOVW_PREL_G0_NC:
 			overflow_check = false;
 			ovf = reloc_insn_movw(RELOC_OP_PREL, loc, val, 0,
-					      INSN_IMM_MOVK);
+					      AARCH64_INSN_IMM_MOVK);
 			break;
 		case R_AARCH64_MOVW_PREL_G0:
 			ovf = reloc_insn_movw(RELOC_OP_PREL, loc, val, 0,
-					      INSN_IMM_MOVNZ);
+					      AARCH64_INSN_IMM_MOVNZ);
 			break;
 		case R_AARCH64_MOVW_PREL_G1_NC:
 			overflow_check = false;
 			ovf = reloc_insn_movw(RELOC_OP_PREL, loc, val, 16,
-					      INSN_IMM_MOVK);
+					      AARCH64_INSN_IMM_MOVK);
 			break;
 		case R_AARCH64_MOVW_PREL_G1:
 			ovf = reloc_insn_movw(RELOC_OP_PREL, loc, val, 16,
-					      INSN_IMM_MOVNZ);
+					      AARCH64_INSN_IMM_MOVNZ);
 			break;
 		case R_AARCH64_MOVW_PREL_G2_NC:
 			overflow_check = false;
 			ovf = reloc_insn_movw(RELOC_OP_PREL, loc, val, 32,
-					      INSN_IMM_MOVK);
+					      AARCH64_INSN_IMM_MOVK);
 			break;
 		case R_AARCH64_MOVW_PREL_G2:
 			ovf = reloc_insn_movw(RELOC_OP_PREL, loc, val, 32,
-					      INSN_IMM_MOVNZ);
+					      AARCH64_INSN_IMM_MOVNZ);
 			break;
 		case R_AARCH64_MOVW_PREL_G3:
 			/* We're using the top bits so we can't overflow. */
 			overflow_check = false;
 			ovf = reloc_insn_movw(RELOC_OP_PREL, loc, val, 48,
-					      INSN_IMM_MOVNZ);
+					      AARCH64_INSN_IMM_MOVNZ);
 			break;
 
 		/* Immediate instruction relocations. */
 		case R_AARCH64_LD_PREL_LO19:
 			ovf = reloc_insn_imm(RELOC_OP_PREL, loc, val, 2, 19,
-					     INSN_IMM_19);
+					     AARCH64_INSN_IMM_19);
 			break;
 		case R_AARCH64_ADR_PREL_LO21:
 			ovf = reloc_insn_imm(RELOC_OP_PREL, loc, val, 0, 21,
-					     INSN_IMM_ADR);
+					     AARCH64_INSN_IMM_ADR);
 			break;
 		case R_AARCH64_ADR_PREL_PG_HI21_NC:
 			overflow_check = false;
 		case R_AARCH64_ADR_PREL_PG_HI21:
 			ovf = reloc_insn_imm(RELOC_OP_PAGE, loc, val, 12, 21,
-					     INSN_IMM_ADR);
+					     AARCH64_INSN_IMM_ADR);
 			break;
 		case R_AARCH64_ADD_ABS_LO12_NC:
 		case R_AARCH64_LDST8_ABS_LO12_NC:
 			overflow_check = false;
 			ovf = reloc_insn_imm(RELOC_OP_ABS, loc, val, 0, 12,
-					     INSN_IMM_12);
+					     AARCH64_INSN_IMM_12);
 			break;
 		case R_AARCH64_LDST16_ABS_LO12_NC:
 			overflow_check = false;
 			ovf = reloc_insn_imm(RELOC_OP_ABS, loc, val, 1, 11,
-					     INSN_IMM_12);
+					     AARCH64_INSN_IMM_12);
 			break;
 		case R_AARCH64_LDST32_ABS_LO12_NC:
 			overflow_check = false;
 			ovf = reloc_insn_imm(RELOC_OP_ABS, loc, val, 2, 10,
-					     INSN_IMM_12);
+					     AARCH64_INSN_IMM_12);
 			break;
 		case R_AARCH64_LDST64_ABS_LO12_NC:
 			overflow_check = false;
 			ovf = reloc_insn_imm(RELOC_OP_ABS, loc, val, 3, 9,
-					     INSN_IMM_12);
+					     AARCH64_INSN_IMM_12);
 			break;
 		case R_AARCH64_LDST128_ABS_LO12_NC:
 			overflow_check = false;
 			ovf = reloc_insn_imm(RELOC_OP_ABS, loc, val, 4, 8,
-					     INSN_IMM_12);
+					     AARCH64_INSN_IMM_12);
 			break;
 		case R_AARCH64_TSTBR14:
 			ovf = reloc_insn_imm(RELOC_OP_PREL, loc, val, 2, 14,
-					     INSN_IMM_14);
+					     AARCH64_INSN_IMM_14);
 			break;
 		case R_AARCH64_CONDBR19:
 			ovf = reloc_insn_imm(RELOC_OP_PREL, loc, val, 2, 19,
-					     INSN_IMM_19);
+					     AARCH64_INSN_IMM_19);
 			break;
 		case R_AARCH64_JUMP26:
 		case R_AARCH64_CALL26:
 			ovf = reloc_insn_imm(RELOC_OP_PREL, loc, val, 2, 26,
-					     INSN_IMM_26);
+					     AARCH64_INSN_IMM_26);
 			break;
 
 		default:
-- 
1.8.1.2