--- /dev/null
+/*
+ * Copyright 2013 Tilera Corporation. All Rights Reserved.
+ *
+ * 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, version 2.
+ *
+ * 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, GOOD TITLE or
+ * NON INFRINGEMENT. See the GNU General Public License for
+ * more details.
+ *
+ * A code-rewriter that handles unaligned exception.
+ */
+
+#include <linux/smp.h>
+#include <linux/ptrace.h>
+#include <linux/slab.h>
+#include <linux/thread_info.h>
+#include <linux/uaccess.h>
+#include <linux/mman.h>
+#include <linux/types.h>
+#include <linux/err.h>
+#include <linux/module.h>
+#include <linux/compat.h>
+#include <linux/prctl.h>
+#include <linux/context_tracking.h>
+#include <asm/cacheflush.h>
+#include <asm/traps.h>
+#include <asm/uaccess.h>
+#include <asm/unaligned.h>
+#include <arch/abi.h>
+#include <arch/spr_def.h>
+#include <arch/opcode.h>
+
+
+/*
+ * This file handles unaligned exception for tile-Gx. The tilepro's unaligned
+ * exception is supported out of single_step.c
+ */
+
+int unaligned_printk;
+
+static int __init setup_unaligned_printk(char *str)
+{
+ long val;
+ if (kstrtol(str, 0, &val) != 0)
+ return 0;
+ unaligned_printk = val;
+ pr_info("Printk for each unaligned data accesses is %s\n",
+ unaligned_printk ? "enabled" : "disabled");
+ return 1;
+}
+__setup("unaligned_printk=", setup_unaligned_printk);
+
+unsigned int unaligned_fixup_count;
+
+#ifdef __tilegx__
+
+/*
+ * Unalign data jit fixup code fragement. Reserved space is 128 bytes.
+ * The 1st 64-bit word saves fault PC address, 2nd word is the fault
+ * instruction bundle followed by 14 JIT bundles.
+ */
+
+struct unaligned_jit_fragment {
+ unsigned long pc;
+ tilegx_bundle_bits bundle;
+ tilegx_bundle_bits insn[14];
+};
+
+/*
+ * Check if a nop or fnop at bundle's pipeline X0.
+ */
+
+static bool is_bundle_x0_nop(tilegx_bundle_bits bundle)
+{
+ return (((get_UnaryOpcodeExtension_X0(bundle) ==
+ NOP_UNARY_OPCODE_X0) &&
+ (get_RRROpcodeExtension_X0(bundle) ==
+ UNARY_RRR_0_OPCODE_X0) &&
+ (get_Opcode_X0(bundle) ==
+ RRR_0_OPCODE_X0)) ||
+ ((get_UnaryOpcodeExtension_X0(bundle) ==
+ FNOP_UNARY_OPCODE_X0) &&
+ (get_RRROpcodeExtension_X0(bundle) ==
+ UNARY_RRR_0_OPCODE_X0) &&
+ (get_Opcode_X0(bundle) ==
+ RRR_0_OPCODE_X0)));
+}
+
+/*
+ * Check if nop or fnop at bundle's pipeline X1.
+ */
+
+static bool is_bundle_x1_nop(tilegx_bundle_bits bundle)
+{
+ return (((get_UnaryOpcodeExtension_X1(bundle) ==
+ NOP_UNARY_OPCODE_X1) &&
+ (get_RRROpcodeExtension_X1(bundle) ==
+ UNARY_RRR_0_OPCODE_X1) &&
+ (get_Opcode_X1(bundle) ==
+ RRR_0_OPCODE_X1)) ||
+ ((get_UnaryOpcodeExtension_X1(bundle) ==
+ FNOP_UNARY_OPCODE_X1) &&
+ (get_RRROpcodeExtension_X1(bundle) ==
+ UNARY_RRR_0_OPCODE_X1) &&
+ (get_Opcode_X1(bundle) ==
+ RRR_0_OPCODE_X1)));
+}
+
+/*
+ * Check if nop or fnop at bundle's Y0 pipeline.
+ */
+
+static bool is_bundle_y0_nop(tilegx_bundle_bits bundle)
+{
+ return (((get_UnaryOpcodeExtension_Y0(bundle) ==
+ NOP_UNARY_OPCODE_Y0) &&
+ (get_RRROpcodeExtension_Y0(bundle) ==
+ UNARY_RRR_1_OPCODE_Y0) &&
+ (get_Opcode_Y0(bundle) ==
+ RRR_1_OPCODE_Y0)) ||
+ ((get_UnaryOpcodeExtension_Y0(bundle) ==
+ FNOP_UNARY_OPCODE_Y0) &&
+ (get_RRROpcodeExtension_Y0(bundle) ==
+ UNARY_RRR_1_OPCODE_Y0) &&
+ (get_Opcode_Y0(bundle) ==
+ RRR_1_OPCODE_Y0)));
+}
+
+/*
+ * Check if nop or fnop at bundle's pipeline Y1.
+ */
+
+static bool is_bundle_y1_nop(tilegx_bundle_bits bundle)
+{
+ return (((get_UnaryOpcodeExtension_Y1(bundle) ==
+ NOP_UNARY_OPCODE_Y1) &&
+ (get_RRROpcodeExtension_Y1(bundle) ==
+ UNARY_RRR_1_OPCODE_Y1) &&
+ (get_Opcode_Y1(bundle) ==
+ RRR_1_OPCODE_Y1)) ||
+ ((get_UnaryOpcodeExtension_Y1(bundle) ==
+ FNOP_UNARY_OPCODE_Y1) &&
+ (get_RRROpcodeExtension_Y1(bundle) ==
+ UNARY_RRR_1_OPCODE_Y1) &&
+ (get_Opcode_Y1(bundle) ==
+ RRR_1_OPCODE_Y1)));
+}
+
+/*
+ * Test if a bundle's y0 and y1 pipelines are both nop or fnop.
+ */
+
+static bool is_y0_y1_nop(tilegx_bundle_bits bundle)
+{
+ return is_bundle_y0_nop(bundle) && is_bundle_y1_nop(bundle);
+}
+
+/*
+ * Test if a bundle's x0 and x1 pipelines are both nop or fnop.
+ */
+
+static bool is_x0_x1_nop(tilegx_bundle_bits bundle)
+{
+ return is_bundle_x0_nop(bundle) && is_bundle_x1_nop(bundle);
+}
+
+/*
+ * Find the destination, source registers of fault unalign access instruction
+ * at X1 or Y2. Also, allocate up to 3 scratch registers clob1, clob2 and
+ * clob3, which are guaranteed different from any register used in the fault
+ * bundle. r_alias is used to return if the other instructions other than the
+ * unalign load/store shares same register with ra, rb and rd.
+ */
+
+static void find_regs(tilegx_bundle_bits bundle, uint64_t *rd, uint64_t *ra,
+ uint64_t *rb, uint64_t *clob1, uint64_t *clob2,
+ uint64_t *clob3, bool *r_alias)
+{
+ int i;
+ uint64_t reg;
+ uint64_t reg_map = 0, alias_reg_map = 0, map;
+ bool alias = false;
+
+ /*
+ * Parse fault bundle, find potential used registers and mark
+ * corresponding bits in reg_map and alias_map. These 2 bit maps
+ * are used to find the scratch registers and determine if there
+ * is register alais.
+ */
+ if (bundle & TILEGX_BUNDLE_MODE_MASK) { /* Y Mode Bundle. */
+
+ reg = get_SrcA_Y2(bundle);
+ reg_map |= 1ULL << reg;
+ *ra = reg;
+ reg = get_SrcBDest_Y2(bundle);
+ reg_map |= 1ULL << reg;
+
+ if (rd) {
+ /* Load. */
+ *rd = reg;
+ alias_reg_map = (1ULL << *rd) | (1ULL << *ra);
+ } else {
+ /* Store. */
+ *rb = reg;
+ alias_reg_map = (1ULL << *ra) | (1ULL << *rb);
+ }
+
+ if (!is_bundle_y1_nop(bundle)) {
+ reg = get_SrcA_Y1(bundle);
+ reg_map |= (1ULL << reg);
+ map = (1ULL << reg);
+
+ reg = get_SrcB_Y1(bundle);
+ reg_map |= (1ULL << reg);
+ map |= (1ULL << reg);
+
+ reg = get_Dest_Y1(bundle);
+ reg_map |= (1ULL << reg);
+ map |= (1ULL << reg);
+
+ if (map & alias_reg_map)
+ alias = true;
+ }
+
+ if (!is_bundle_y0_nop(bundle)) {
+ reg = get_SrcA_Y0(bundle);
+ reg_map |= (1ULL << reg);
+ map = (1ULL << reg);
+
+ reg = get_SrcB_Y0(bundle);
+ reg_map |= (1ULL << reg);
+ map |= (1ULL << reg);
+
+ reg = get_Dest_Y0(bundle);
+ reg_map |= (1ULL << reg);
+ map |= (1ULL << reg);
+
+ if (map & alias_reg_map)
+ alias = true;
+ }
+ } else { /* X Mode Bundle. */
+
+ reg = get_SrcA_X1(bundle);
+ reg_map |= (1ULL << reg);
+ *ra = reg;
+ if (rd) {
+ /* Load. */
+ reg = get_Dest_X1(bundle);
+ reg_map |= (1ULL << reg);
+ *rd = reg;
+ alias_reg_map = (1ULL << *rd) | (1ULL << *ra);
+ } else {
+ /* Store. */
+ reg = get_SrcB_X1(bundle);
+ reg_map |= (1ULL << reg);
+ *rb = reg;
+ alias_reg_map = (1ULL << *ra) | (1ULL << *rb);
+ }
+
+ if (!is_bundle_x0_nop(bundle)) {
+ reg = get_SrcA_X0(bundle);
+ reg_map |= (1ULL << reg);
+ map = (1ULL << reg);
+
+ reg = get_SrcB_X0(bundle);
+ reg_map |= (1ULL << reg);
+ map |= (1ULL << reg);
+
+ reg = get_Dest_X0(bundle);
+ reg_map |= (1ULL << reg);
+ map |= (1ULL << reg);
+
+ if (map & alias_reg_map)
+ alias = true;
+ }
+ }
+
+ /*
+ * "alias" indicates if the unalign access registers have collision
+ * with others in the same bundle. We jsut simply test all register
+ * operands case (RRR), ignored the case with immidate. If a bundle
+ * has no register alias, we may do fixup in a simple or fast manner.
+ * So if an immidata field happens to hit with a register, we may end
+ * up fall back to the generic handling.
+ */
+
+ *r_alias = alias;
+
+ /* Flip bits on reg_map. */
+ reg_map ^= -1ULL;
+
+ /* Scan reg_map lower 54(TREG_SP) bits to find 3 set bits. */
+ for (i = 0; i < TREG_SP; i++) {
+ if (reg_map & (0x1ULL << i)) {
+ if (*clob1 == -1) {
+ *clob1 = i;
+ } else if (*clob2 == -1) {
+ *clob2 = i;
+ } else if (*clob3 == -1) {
+ *clob3 = i;
+ return;
+ }
+ }
+ }
+}
+
+/*
+ * Sanity check for register ra, rb, rd, clob1/2/3. Return true if any of them
+ * is unexpected.
+ */
+
+static bool check_regs(uint64_t rd, uint64_t ra, uint64_t rb,
+ uint64_t clob1, uint64_t clob2, uint64_t clob3)
+{
+ bool unexpected = false;
+ if ((ra >= 56) && (ra != TREG_ZERO))
+ unexpected = true;
+
+ if ((clob1 >= 56) || (clob2 >= 56) || (clob3 >= 56))
+ unexpected = true;
+
+ if (rd != -1) {
+ if ((rd >= 56) && (rd != TREG_ZERO))
+ unexpected = true;
+ } else {
+ if ((rb >= 56) && (rb != TREG_ZERO))
+ unexpected = true;
+ }
+ return unexpected;
+}
+
+
+#define GX_INSN_X0_MASK ((1ULL << 31) - 1)
+#define GX_INSN_X1_MASK (((1ULL << 31) - 1) << 31)
+#define GX_INSN_Y0_MASK ((0xFULL << 27) | (0xFFFFFULL))
+#define GX_INSN_Y1_MASK (GX_INSN_Y0_MASK << 31)
+#define GX_INSN_Y2_MASK ((0x7FULL << 51) | (0x7FULL << 20))
+
+#ifdef __LITTLE_ENDIAN
+#define GX_INSN_BSWAP(_bundle_) (_bundle_)
+#else
+#define GX_INSN_BSWAP(_bundle_) swab64(_bundle_)
+#endif /* __LITTLE_ENDIAN */
+
+/*
+ * __JIT_CODE(.) creates template bundles in .rodata.unalign_data section.
+ * The corresponding static function jix_x#_###(.) generates partial or
+ * whole bundle based on the template and given arguments.
+ */
+
+#define __JIT_CODE(_X_) \
+ asm (".pushsection .rodata.unalign_data, \"a\"\n" \
+ _X_"\n" \
+ ".popsection\n")
+
+__JIT_CODE("__unalign_jit_x1_mtspr: {mtspr 0, r0}");
+static tilegx_bundle_bits jit_x1_mtspr(int spr, int reg)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_mtspr;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_mtspr) & GX_INSN_X1_MASK) |
+ create_MT_Imm14_X1(spr) | create_SrcA_X1(reg);
+}
+
+__JIT_CODE("__unalign_jit_x1_mfspr: {mfspr r0, 0}");
+static tilegx_bundle_bits jit_x1_mfspr(int reg, int spr)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_mfspr;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_mfspr) & GX_INSN_X1_MASK) |
+ create_MF_Imm14_X1(spr) | create_Dest_X1(reg);
+}
+
+__JIT_CODE("__unalign_jit_x0_addi: {addi r0, r0, 0; iret}");
+static tilegx_bundle_bits jit_x0_addi(int rd, int ra, int imm8)
+{
+ extern tilegx_bundle_bits __unalign_jit_x0_addi;
+ return (GX_INSN_BSWAP(__unalign_jit_x0_addi) & GX_INSN_X0_MASK) |
+ create_Dest_X0(rd) | create_SrcA_X0(ra) |
+ create_Imm8_X0(imm8);
+}
+
+__JIT_CODE("__unalign_jit_x1_ldna: {ldna r0, r0}");
+static tilegx_bundle_bits jit_x1_ldna(int rd, int ra)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_ldna;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_ldna) & GX_INSN_X1_MASK) |
+ create_Dest_X1(rd) | create_SrcA_X1(ra);
+}
+
+__JIT_CODE("__unalign_jit_x0_dblalign: {dblalign r0, r0 ,r0}");
+static tilegx_bundle_bits jit_x0_dblalign(int rd, int ra, int rb)
+{
+ extern tilegx_bundle_bits __unalign_jit_x0_dblalign;
+ return (GX_INSN_BSWAP(__unalign_jit_x0_dblalign) & GX_INSN_X0_MASK) |
+ create_Dest_X0(rd) | create_SrcA_X0(ra) |
+ create_SrcB_X0(rb);
+}
+
+__JIT_CODE("__unalign_jit_x1_iret: {iret}");
+static tilegx_bundle_bits jit_x1_iret(void)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_iret;
+ return GX_INSN_BSWAP(__unalign_jit_x1_iret) & GX_INSN_X1_MASK;
+}
+
+__JIT_CODE("__unalign_jit_x01_fnop: {fnop;fnop}");
+static tilegx_bundle_bits jit_x0_fnop(void)
+{
+ extern tilegx_bundle_bits __unalign_jit_x01_fnop;
+ return GX_INSN_BSWAP(__unalign_jit_x01_fnop) & GX_INSN_X0_MASK;
+}
+
+static tilegx_bundle_bits jit_x1_fnop(void)
+{
+ extern tilegx_bundle_bits __unalign_jit_x01_fnop;
+ return GX_INSN_BSWAP(__unalign_jit_x01_fnop) & GX_INSN_X1_MASK;
+}
+
+__JIT_CODE("__unalign_jit_y2_dummy: {fnop; fnop; ld zero, sp}");
+static tilegx_bundle_bits jit_y2_dummy(void)
+{
+ extern tilegx_bundle_bits __unalign_jit_y2_dummy;
+ return GX_INSN_BSWAP(__unalign_jit_y2_dummy) & GX_INSN_Y2_MASK;
+}
+
+static tilegx_bundle_bits jit_y1_fnop(void)
+{
+ extern tilegx_bundle_bits __unalign_jit_y2_dummy;
+ return GX_INSN_BSWAP(__unalign_jit_y2_dummy) & GX_INSN_Y1_MASK;
+}
+
+__JIT_CODE("__unalign_jit_x1_st1_add: {st1_add r1, r0, 0}");
+static tilegx_bundle_bits jit_x1_st1_add(int ra, int rb, int imm8)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_st1_add;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_st1_add) &
+ (~create_SrcA_X1(-1)) &
+ GX_INSN_X1_MASK) | create_SrcA_X1(ra) |
+ create_SrcB_X1(rb) | create_Dest_Imm8_X1(imm8);
+}
+
+__JIT_CODE("__unalign_jit_x1_st: {crc32_8 r1, r0, r0; st r0, r0}");
+static tilegx_bundle_bits jit_x1_st(int ra, int rb)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_st;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_st) & GX_INSN_X1_MASK) |
+ create_SrcA_X1(ra) | create_SrcB_X1(rb);
+}
+
+__JIT_CODE("__unalign_jit_x1_st_add: {st_add r1, r0, 0}");
+static tilegx_bundle_bits jit_x1_st_add(int ra, int rb, int imm8)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_st_add;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_st_add) &
+ (~create_SrcA_X1(-1)) &
+ GX_INSN_X1_MASK) | create_SrcA_X1(ra) |
+ create_SrcB_X1(rb) | create_Dest_Imm8_X1(imm8);
+}
+
+__JIT_CODE("__unalign_jit_x1_ld: {crc32_8 r1, r0, r0; ld r0, r0}");
+static tilegx_bundle_bits jit_x1_ld(int rd, int ra)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_ld;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_ld) & GX_INSN_X1_MASK) |
+ create_Dest_X1(rd) | create_SrcA_X1(ra);
+}
+
+__JIT_CODE("__unalign_jit_x1_ld_add: {ld_add r1, r0, 0}");
+static tilegx_bundle_bits jit_x1_ld_add(int rd, int ra, int imm8)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_ld_add;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_ld_add) &
+ (~create_Dest_X1(-1)) &
+ GX_INSN_X1_MASK) | create_Dest_X1(rd) |
+ create_SrcA_X1(ra) | create_Imm8_X1(imm8);
+}
+
+__JIT_CODE("__unalign_jit_x0_bfexts: {bfexts r0, r0, 0, 0}");
+static tilegx_bundle_bits jit_x0_bfexts(int rd, int ra, int bfs, int bfe)
+{
+ extern tilegx_bundle_bits __unalign_jit_x0_bfexts;
+ return (GX_INSN_BSWAP(__unalign_jit_x0_bfexts) &
+ GX_INSN_X0_MASK) |
+ create_Dest_X0(rd) | create_SrcA_X0(ra) |
+ create_BFStart_X0(bfs) | create_BFEnd_X0(bfe);
+}
+
+__JIT_CODE("__unalign_jit_x0_bfextu: {bfextu r0, r0, 0, 0}");
+static tilegx_bundle_bits jit_x0_bfextu(int rd, int ra, int bfs, int bfe)
+{
+ extern tilegx_bundle_bits __unalign_jit_x0_bfextu;
+ return (GX_INSN_BSWAP(__unalign_jit_x0_bfextu) &
+ GX_INSN_X0_MASK) |
+ create_Dest_X0(rd) | create_SrcA_X0(ra) |
+ create_BFStart_X0(bfs) | create_BFEnd_X0(bfe);
+}
+
+__JIT_CODE("__unalign_jit_x1_addi: {bfextu r1, r1, 0, 0; addi r0, r0, 0}");
+static tilegx_bundle_bits jit_x1_addi(int rd, int ra, int imm8)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_addi;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_addi) & GX_INSN_X1_MASK) |
+ create_Dest_X1(rd) | create_SrcA_X1(ra) |
+ create_Imm8_X1(imm8);
+}
+
+__JIT_CODE("__unalign_jit_x0_shrui: {shrui r0, r0, 0; iret}");
+static tilegx_bundle_bits jit_x0_shrui(int rd, int ra, int imm6)
+{
+ extern tilegx_bundle_bits __unalign_jit_x0_shrui;
+ return (GX_INSN_BSWAP(__unalign_jit_x0_shrui) &
+ GX_INSN_X0_MASK) |
+ create_Dest_X0(rd) | create_SrcA_X0(ra) |
+ create_ShAmt_X0(imm6);
+}
+
+__JIT_CODE("__unalign_jit_x0_rotli: {rotli r0, r0, 0; iret}");
+static tilegx_bundle_bits jit_x0_rotli(int rd, int ra, int imm6)
+{
+ extern tilegx_bundle_bits __unalign_jit_x0_rotli;
+ return (GX_INSN_BSWAP(__unalign_jit_x0_rotli) &
+ GX_INSN_X0_MASK) |
+ create_Dest_X0(rd) | create_SrcA_X0(ra) |
+ create_ShAmt_X0(imm6);
+}
+
+__JIT_CODE("__unalign_jit_x1_bnezt: {bnezt r0, __unalign_jit_x1_bnezt}");
+static tilegx_bundle_bits jit_x1_bnezt(int ra, int broff)
+{
+ extern tilegx_bundle_bits __unalign_jit_x1_bnezt;
+ return (GX_INSN_BSWAP(__unalign_jit_x1_bnezt) &
+ GX_INSN_X1_MASK) |
+ create_SrcA_X1(ra) | create_BrOff_X1(broff);
+}
+
+#undef __JIT_CODE
+
+/*
+ * This function generates unalign fixup JIT.
+ *
+ * We first find unalign load/store instruction's destination, source
+ * registers: ra, rb and rd. and 3 scratch registers by calling
+ * find_regs(...). 3 scratch clobbers should not alias with any register
+ * used in the fault bundle. Then analyze the fault bundle to determine
+ * if it's a load or store, operand width, branch or address increment etc.
+ * At last generated JIT is copied into JIT code area in user space.
+ */
+
+static
+void jit_bundle_gen(struct pt_regs *regs, tilegx_bundle_bits bundle,
+ int align_ctl)
+{
+ struct thread_info *info = current_thread_info();
+ struct unaligned_jit_fragment frag;
+ struct unaligned_jit_fragment *jit_code_area;
+ tilegx_bundle_bits bundle_2 = 0;
+ /* If bundle_2_enable = false, bundle_2 is fnop/nop operation. */
+ bool bundle_2_enable = true;
+ uint64_t ra = -1, rb = -1, rd = -1, clob1 = -1, clob2 = -1, clob3 = -1;
+ /*
+ * Indicate if the unalign access
+ * instruction's registers hit with
+ * others in the same bundle.
+ */
+ bool alias = false;
+ bool load_n_store = true;
+ bool load_store_signed = false;
+ unsigned int load_store_size = 8;
+ bool y1_br = false; /* True, for a branch in same bundle at Y1.*/
+ int y1_br_reg = 0;
+ /* True for link operation. i.e. jalr or lnk at Y1 */
+ bool y1_lr = false;
+ int y1_lr_reg = 0;
+ bool x1_add = false;/* True, for load/store ADD instruction at X1*/
+ int x1_add_imm8 = 0;
+ bool unexpected = false;
+ int n = 0, k;
+
+ jit_code_area =
+ (struct unaligned_jit_fragment *)(info->unalign_jit_base);
+
+ memset((void *)&frag, 0, sizeof(frag));
+
+ /* 0: X mode, Otherwise: Y mode. */
+ if (bundle & TILEGX_BUNDLE_MODE_MASK) {
+ unsigned int mod, opcode;
+
+ if (get_Opcode_Y1(bundle) == RRR_1_OPCODE_Y1 &&
+ get_RRROpcodeExtension_Y1(bundle) ==
+ UNARY_RRR_1_OPCODE_Y1) {
+
+ opcode = get_UnaryOpcodeExtension_Y1(bundle);
+
+ /*
+ * Test "jalr", "jalrp", "jr", "jrp" instruction at Y1
+ * pipeline.
+ */
+ switch (opcode) {
+ case JALR_UNARY_OPCODE_Y1:
+ case JALRP_UNARY_OPCODE_Y1:
+ y1_lr = true;
+ y1_lr_reg = 55; /* Link register. */
+ /* FALLTHROUGH */
+ case JR_UNARY_OPCODE_Y1:
+ case JRP_UNARY_OPCODE_Y1:
+ y1_br = true;
+ y1_br_reg = get_SrcA_Y1(bundle);
+ break;
+ case LNK_UNARY_OPCODE_Y1:
+ /* "lnk" at Y1 pipeline. */
+ y1_lr = true;
+ y1_lr_reg = get_Dest_Y1(bundle);
+ break;
+ }
+ }
+
+ opcode = get_Opcode_Y2(bundle);
+ mod = get_Mode(bundle);
+
+ /*
+ * bundle_2 is bundle after making Y2 as a dummy operation
+ * - ld zero, sp
+ */
+ bundle_2 = (bundle & (~GX_INSN_Y2_MASK)) | jit_y2_dummy();
+
+ /* Make Y1 as fnop if Y1 is a branch or lnk operation. */
+ if (y1_br || y1_lr) {
+ bundle_2 &= ~(GX_INSN_Y1_MASK);
+ bundle_2 |= jit_y1_fnop();
+ }
+
+ if (is_y0_y1_nop(bundle_2))
+ bundle_2_enable = false;
+
+ if (mod == MODE_OPCODE_YC2) {
+ /* Store. */
+ load_n_store = false;
+ load_store_size = 1 << opcode;
+ load_store_signed = false;
+ find_regs(bundle, 0, &ra, &rb, &clob1, &clob2,
+ &clob3, &alias);
+ if (load_store_size > 8)
+ unexpected = true;
+ } else {
+ /* Load. */
+ load_n_store = true;
+ if (mod == MODE_OPCODE_YB2) {
+ switch (opcode) {
+ case LD_OPCODE_Y2:
+ load_store_signed = false;
+ load_store_size = 8;
+ break;
+ case LD4S_OPCODE_Y2:
+ load_store_signed = true;
+ load_store_size = 4;
+ break;
+ case LD4U_OPCODE_Y2:
+ load_store_signed = false;
+ load_store_size = 4;
+ break;
+ default:
+ unexpected = true;
+ }
+ } else if (mod == MODE_OPCODE_YA2) {
+ if (opcode == LD2S_OPCODE_Y2) {
+ load_store_signed = true;
+ load_store_size = 2;
+ } else if (opcode == LD2U_OPCODE_Y2) {
+ load_store_signed = false;
+ load_store_size = 2;
+ } else
+ unexpected = true;
+ } else
+ unexpected = true;
+ find_regs(bundle, &rd, &ra, &rb, &clob1, &clob2,
+ &clob3, &alias);
+ }
+ } else {
+ unsigned int opcode;
+
+ /* bundle_2 is bundle after making X1 as "fnop". */
+ bundle_2 = (bundle & (~GX_INSN_X1_MASK)) | jit_x1_fnop();
+
+ if (is_x0_x1_nop(bundle_2))
+ bundle_2_enable = false;
+
+ if (get_Opcode_X1(bundle) == RRR_0_OPCODE_X1) {
+ opcode = get_UnaryOpcodeExtension_X1(bundle);
+
+ if (get_RRROpcodeExtension_X1(bundle) ==
+ UNARY_RRR_0_OPCODE_X1) {
+ load_n_store = true;
+ find_regs(bundle, &rd, &ra, &rb, &clob1,
+ &clob2, &clob3, &alias);
+
+ switch (opcode) {
+ case LD_UNARY_OPCODE_X1:
+ load_store_signed = false;
+ load_store_size = 8;
+ break;
+ case LD4S_UNARY_OPCODE_X1:
+ load_store_signed = true;
+ /* FALLTHROUGH */
+ case LD4U_UNARY_OPCODE_X1:
+ load_store_size = 4;
+ break;
+
+ case LD2S_UNARY_OPCODE_X1:
+ load_store_signed = true;
+ /* FALLTHROUGH */
+ case LD2U_UNARY_OPCODE_X1:
+ load_store_size = 2;
+ break;
+ default:
+ unexpected = true;
+ }
+ } else {
+ load_n_store = false;
+ load_store_signed = false;
+ find_regs(bundle, 0, &ra, &rb,
+ &clob1, &clob2, &clob3,
+ &alias);
+
+ opcode = get_RRROpcodeExtension_X1(bundle);
+ switch (opcode) {
+ case ST_RRR_0_OPCODE_X1:
+ load_store_size = 8;
+ break;
+ case ST4_RRR_0_OPCODE_X1:
+ load_store_size = 4;
+ break;
+ case ST2_RRR_0_OPCODE_X1:
+ load_store_size = 2;
+ break;
+ default:
+ unexpected = true;
+ }
+ }
+ } else if (get_Opcode_X1(bundle) == IMM8_OPCODE_X1) {
+ load_n_store = true;
+ opcode = get_Imm8OpcodeExtension_X1(bundle);
+ switch (opcode) {
+ case LD_ADD_IMM8_OPCODE_X1:
+ load_store_size = 8;
+ break;
+
+ case LD4S_ADD_IMM8_OPCODE_X1:
+ load_store_signed = true;
+ /* FALLTHROUGH */
+ case LD4U_ADD_IMM8_OPCODE_X1:
+ load_store_size = 4;
+ break;
+
+ case LD2S_ADD_IMM8_OPCODE_X1:
+ load_store_signed = true;
+ /* FALLTHROUGH */
+ case LD2U_ADD_IMM8_OPCODE_X1:
+ load_store_size = 2;
+ break;
+
+ case ST_ADD_IMM8_OPCODE_X1:
+ load_n_store = false;
+ load_store_size = 8;
+ break;
+ case ST4_ADD_IMM8_OPCODE_X1:
+ load_n_store = false;
+ load_store_size = 4;
+ break;
+ case ST2_ADD_IMM8_OPCODE_X1:
+ load_n_store = false;
+ load_store_size = 2;
+ break;
+ default:
+ unexpected = true;
+ }
+
+ if (!unexpected) {
+ x1_add = true;
+ if (load_n_store)
+ x1_add_imm8 = get_Imm8_X1(bundle);
+ else
+ x1_add_imm8 = get_Dest_Imm8_X1(bundle);
+ }
+
+ find_regs(bundle, load_n_store ? (&rd) : NULL,
+ &ra, &rb, &clob1, &clob2, &clob3, &alias);
+ } else
+ unexpected = true;
+ }
+
+ /*
+ * Some sanity check for register numbers extracted from fault bundle.
+ */
+ if (check_regs(rd, ra, rb, clob1, clob2, clob3) == true)
+ unexpected = true;
+
+ /* Give warning if register ra has an aligned address. */
+ if (!unexpected)
+ WARN_ON(!((load_store_size - 1) & (regs->regs[ra])));
+
+
+ /*
+ * Fault came from kernel space, here we only need take care of
+ * unaligned "get_user/put_user" macros defined in "uaccess.h".
+ * Basically, we will handle bundle like this:
+ * {ld/2u/4s rd, ra; movei rx, 0} or {st/2/4 ra, rb; movei rx, 0}
+ * (Refer to file "arch/tile/include/asm/uaccess.h" for details).
+ * For either load or store, byte-wise operation is performed by calling
+ * get_user() or put_user(). If the macro returns non-zero value,
+ * set the value to rx, otherwise set zero to rx. Finally make pc point
+ * to next bundle and return.
+ */
+
+ if (EX1_PL(regs->ex1) != USER_PL) {
+
+ unsigned long rx = 0;
+ unsigned long x = 0, ret = 0;
+
+ if (y1_br || y1_lr || x1_add ||
+ (load_store_signed !=
+ (load_n_store && load_store_size == 4))) {
+ /* No branch, link, wrong sign-ext or load/store add. */
+ unexpected = true;
+ } else if (!unexpected) {
+ if (bundle & TILEGX_BUNDLE_MODE_MASK) {
+ /*
+ * Fault bundle is Y mode.
+ * Check if the Y1 and Y0 is the form of
+ * { movei rx, 0; nop/fnop }, if yes,
+ * find the rx.
+ */
+
+ if ((get_Opcode_Y1(bundle) == ADDI_OPCODE_Y1)
+ && (get_SrcA_Y1(bundle) == TREG_ZERO) &&
+ (get_Imm8_Y1(bundle) == 0) &&
+ is_bundle_y0_nop(bundle)) {
+ rx = get_Dest_Y1(bundle);
+ } else if ((get_Opcode_Y0(bundle) ==
+ ADDI_OPCODE_Y0) &&
+ (get_SrcA_Y0(bundle) == TREG_ZERO) &&
+ (get_Imm8_Y0(bundle) == 0) &&
+ is_bundle_y1_nop(bundle)) {
+ rx = get_Dest_Y0(bundle);
+ } else {
+ unexpected = true;
+ }
+ } else {
+ /*
+ * Fault bundle is X mode.
+ * Check if the X0 is 'movei rx, 0',
+ * if yes, find the rx.
+ */
+
+ if ((get_Opcode_X0(bundle) == IMM8_OPCODE_X0)
+ && (get_Imm8OpcodeExtension_X0(bundle) ==
+ ADDI_IMM8_OPCODE_X0) &&
+ (get_SrcA_X0(bundle) == TREG_ZERO) &&
+ (get_Imm8_X0(bundle) == 0)) {
+ rx = get_Dest_X0(bundle);
+ } else {
+ unexpected = true;
+ }
+ }
+
+ /* rx should be less than 56. */
+ if (!unexpected && (rx >= 56))
+ unexpected = true;
+ }
+
+ if (!search_exception_tables(regs->pc)) {
+ /* No fixup in the exception tables for the pc. */
+ unexpected = true;
+ }
+
+ if (unexpected) {
+ /* Unexpected unalign kernel fault. */
+ struct task_struct *tsk = validate_current();
+
+ bust_spinlocks(1);
+
+ show_regs(regs);
+
+ if (unlikely(tsk->pid < 2)) {
+ panic("Kernel unalign fault running %s!",
+ tsk->pid ? "init" : "the idle task");
+ }
+#ifdef SUPPORT_DIE
+ die("Oops", regs);
+#endif
+ bust_spinlocks(1);
+
+ do_group_exit(SIGKILL);
+
+ } else {
+ unsigned long i, b = 0;
+ unsigned char *ptr =
+ (unsigned char *)regs->regs[ra];
+ if (load_n_store) {
+ /* handle get_user(x, ptr) */
+ for (i = 0; i < load_store_size; i++) {
+ ret = get_user(b, ptr++);
+ if (!ret) {
+ /* Success! update x. */
+#ifdef __LITTLE_ENDIAN
+ x |= (b << (8 * i));
+#else
+ x <<= 8;
+ x |= b;
+#endif /* __LITTLE_ENDIAN */
+ } else {
+ x = 0;
+ break;
+ }
+ }
+
+ /* Sign-extend 4-byte loads. */
+ if (load_store_size == 4)
+ x = (long)(int)x;
+
+ /* Set register rd. */
+ regs->regs[rd] = x;
+
+ /* Set register rx. */
+ regs->regs[rx] = ret;
+
+ /* Bump pc. */
+ regs->pc += 8;
+
+ } else {
+ /* Handle put_user(x, ptr) */
+ x = regs->regs[rb];
+#ifdef __LITTLE_ENDIAN
+ b = x;
+#else
+ /*
+ * Swap x in order to store x from low
+ * to high memory same as the
+ * little-endian case.
+ */
+ switch (load_store_size) {
+ case 8:
+ b = swab64(x);
+ break;
+ case 4:
+ b = swab32(x);
+ break;
+ case 2:
+ b = swab16(x);
+ break;
+ }
+#endif /* __LITTLE_ENDIAN */
+ for (i = 0; i < load_store_size; i++) {
+ ret = put_user(b, ptr++);
+ if (ret)
+ break;
+ /* Success! shift 1 byte. */
+ b >>= 8;
+ }
+ /* Set register rx. */
+ regs->regs[rx] = ret;
+
+ /* Bump pc. */
+ regs->pc += 8;
+ }
+ }
+
+ unaligned_fixup_count++;
+
+ if (unaligned_printk) {
+ pr_info("%s/%d - Unalign fixup for kernel access to userspace %lx\n",
+ current->comm, current->pid, regs->regs[ra]);
+ }
+
+ /* Done! Return to the exception handler. */
+ return;
+ }
+
+ if ((align_ctl == 0) || unexpected) {
+ siginfo_t info = {
+ .si_signo = SIGBUS,
+ .si_code = BUS_ADRALN,
+ .si_addr = (unsigned char __user *)0
+ };
+ if (unaligned_printk)
+ pr_info("Unalign bundle: unexp @%llx, %llx\n",
+ (unsigned long long)regs->pc,
+ (unsigned long long)bundle);
+
+ if (ra < 56) {
+ unsigned long uaa = (unsigned long)regs->regs[ra];
+ /* Set bus Address. */
+ info.si_addr = (unsigned char __user *)uaa;
+ }
+
+ unaligned_fixup_count++;
+
+ trace_unhandled_signal("unaligned fixup trap", regs,
+ (unsigned long)info.si_addr, SIGBUS);
+ force_sig_info(info.si_signo, &info, current);
+ return;
+ }
+
+#ifdef __LITTLE_ENDIAN
+#define UA_FIXUP_ADDR_DELTA 1
+#define UA_FIXUP_BFEXT_START(_B_) 0
+#define UA_FIXUP_BFEXT_END(_B_) (8 * (_B_) - 1)
+#else /* __BIG_ENDIAN */
+#define UA_FIXUP_ADDR_DELTA -1
+#define UA_FIXUP_BFEXT_START(_B_) (64 - 8 * (_B_))
+#define UA_FIXUP_BFEXT_END(_B_) 63
+#endif /* __LITTLE_ENDIAN */
+
+
+
+ if ((ra != rb) && (rd != TREG_SP) && !alias &&
+ !y1_br && !y1_lr && !x1_add) {
+ /*
+ * Simple case: ra != rb and no register alias found,
+ * and no branch or link. This will be the majority.
+ * We can do a little better for simplae case than the
+ * generic scheme below.
+ */
+ if (!load_n_store) {
+ /*
+ * Simple store: ra != rb, no need for scratch register.
+ * Just store and rotate to right bytewise.
+ */
+#ifdef __BIG_ENDIAN
+ frag.insn[n++] =
+ jit_x0_addi(ra, ra, load_store_size - 1) |
+ jit_x1_fnop();
+#endif /* __BIG_ENDIAN */
+ for (k = 0; k < load_store_size; k++) {
+ /* Store a byte. */
+ frag.insn[n++] =
+ jit_x0_rotli(rb, rb, 56) |
+ jit_x1_st1_add(ra, rb,
+ UA_FIXUP_ADDR_DELTA);
+ }
+#ifdef __BIG_ENDIAN
+ frag.insn[n] = jit_x1_addi(ra, ra, 1);
+#else
+ frag.insn[n] = jit_x1_addi(ra, ra,
+ -1 * load_store_size);
+#endif /* __LITTLE_ENDIAN */
+
+ if (load_store_size == 8) {
+ frag.insn[n] |= jit_x0_fnop();
+ } else if (load_store_size == 4) {
+ frag.insn[n] |= jit_x0_rotli(rb, rb, 32);
+ } else { /* = 2 */
+ frag.insn[n] |= jit_x0_rotli(rb, rb, 16);
+ }
+ n++;
+ if (bundle_2_enable)
+ frag.insn[n++] = bundle_2;
+ frag.insn[n++] = jit_x0_fnop() | jit_x1_iret();
+ } else {
+ if (rd == ra) {
+ /* Use two clobber registers: clob1/2. */
+ frag.insn[n++] =
+ jit_x0_addi(TREG_SP, TREG_SP, -16) |
+ jit_x1_fnop();
+ frag.insn[n++] =
+ jit_x0_addi(clob1, ra, 7) |
+ jit_x1_st_add(TREG_SP, clob1, -8);
+ frag.insn[n++] =
+ jit_x0_addi(clob2, ra, 0) |
+ jit_x1_st(TREG_SP, clob2);
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ldna(rd, ra);
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ldna(clob1, clob1);
+ /*
+ * Note: we must make sure that rd must not
+ * be sp. Recover clob1/2 from stack.
+ */
+ frag.insn[n++] =
+ jit_x0_dblalign(rd, clob1, clob2) |
+ jit_x1_ld_add(clob2, TREG_SP, 8);
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ld_add(clob1, TREG_SP, 16);
+ } else {
+ /* Use one clobber register: clob1 only. */
+ frag.insn[n++] =
+ jit_x0_addi(TREG_SP, TREG_SP, -16) |
+ jit_x1_fnop();
+ frag.insn[n++] =
+ jit_x0_addi(clob1, ra, 7) |
+ jit_x1_st(TREG_SP, clob1);
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ldna(rd, ra);
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ldna(clob1, clob1);
+ /*
+ * Note: we must make sure that rd must not
+ * be sp. Recover clob1 from stack.
+ */
+ frag.insn[n++] =
+ jit_x0_dblalign(rd, clob1, ra) |
+ jit_x1_ld_add(clob1, TREG_SP, 16);
+ }
+
+ if (bundle_2_enable)
+ frag.insn[n++] = bundle_2;
+ /*
+ * For non 8-byte load, extract corresponding bytes and
+ * signed extension.
+ */
+ if (load_store_size == 4) {
+ if (load_store_signed)
+ frag.insn[n++] =
+ jit_x0_bfexts(
+ rd, rd,
+ UA_FIXUP_BFEXT_START(4),
+ UA_FIXUP_BFEXT_END(4)) |
+ jit_x1_fnop();
+ else
+ frag.insn[n++] =
+ jit_x0_bfextu(
+ rd, rd,
+ UA_FIXUP_BFEXT_START(4),
+ UA_FIXUP_BFEXT_END(4)) |
+ jit_x1_fnop();
+ } else if (load_store_size == 2) {
+ if (load_store_signed)
+ frag.insn[n++] =
+ jit_x0_bfexts(
+ rd, rd,
+ UA_FIXUP_BFEXT_START(2),
+ UA_FIXUP_BFEXT_END(2)) |
+ jit_x1_fnop();
+ else
+ frag.insn[n++] =
+ jit_x0_bfextu(
+ rd, rd,
+ UA_FIXUP_BFEXT_START(2),
+ UA_FIXUP_BFEXT_END(2)) |
+ jit_x1_fnop();
+ }
+
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_iret();
+ }
+ } else if (!load_n_store) {
+
+ /*
+ * Generic memory store cases: use 3 clobber registers.
+ *
+ * Alloc space for saveing clob2,1,3 on user's stack.
+ * register clob3 points to where clob2 saved, followed by
+ * clob1 and 3 from high to low memory.
+ */
+ frag.insn[n++] =
+ jit_x0_addi(TREG_SP, TREG_SP, -32) |
+ jit_x1_fnop();
+ frag.insn[n++] =
+ jit_x0_addi(clob3, TREG_SP, 16) |
+ jit_x1_st_add(TREG_SP, clob3, 8);
+#ifdef __LITTLE_ENDIAN
+ frag.insn[n++] =
+ jit_x0_addi(clob1, ra, 0) |
+ jit_x1_st_add(TREG_SP, clob1, 8);
+#else
+ frag.insn[n++] =
+ jit_x0_addi(clob1, ra, load_store_size - 1) |
+ jit_x1_st_add(TREG_SP, clob1, 8);
+#endif
+ if (load_store_size == 8) {
+ /*
+ * We save one byte a time, not for fast, but compact
+ * code. After each store, data source register shift
+ * right one byte. unchanged after 8 stores.
+ */
+ frag.insn[n++] =
+ jit_x0_addi(clob2, TREG_ZERO, 7) |
+ jit_x1_st_add(TREG_SP, clob2, 16);
+ frag.insn[n++] =
+ jit_x0_rotli(rb, rb, 56) |
+ jit_x1_st1_add(clob1, rb, UA_FIXUP_ADDR_DELTA);
+ frag.insn[n++] =
+ jit_x0_addi(clob2, clob2, -1) |
+ jit_x1_bnezt(clob2, -1);
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_addi(clob2, y1_br_reg, 0);
+ } else if (load_store_size == 4) {
+ frag.insn[n++] =
+ jit_x0_addi(clob2, TREG_ZERO, 3) |
+ jit_x1_st_add(TREG_SP, clob2, 16);
+ frag.insn[n++] =
+ jit_x0_rotli(rb, rb, 56) |
+ jit_x1_st1_add(clob1, rb, UA_FIXUP_ADDR_DELTA);
+ frag.insn[n++] =
+ jit_x0_addi(clob2, clob2, -1) |
+ jit_x1_bnezt(clob2, -1);
+ /*
+ * same as 8-byte case, but need shift another 4
+ * byte to recover rb for 4-byte store.
+ */
+ frag.insn[n++] = jit_x0_rotli(rb, rb, 32) |
+ jit_x1_addi(clob2, y1_br_reg, 0);
+ } else { /* =2 */
+ frag.insn[n++] =
+ jit_x0_addi(clob2, rb, 0) |
+ jit_x1_st_add(TREG_SP, clob2, 16);
+ for (k = 0; k < 2; k++) {
+ frag.insn[n++] =
+ jit_x0_shrui(rb, rb, 8) |
+ jit_x1_st1_add(clob1, rb,
+ UA_FIXUP_ADDR_DELTA);
+ }
+ frag.insn[n++] =
+ jit_x0_addi(rb, clob2, 0) |
+ jit_x1_addi(clob2, y1_br_reg, 0);
+ }
+
+ if (bundle_2_enable)
+ frag.insn[n++] = bundle_2;
+
+ if (y1_lr) {
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_mfspr(y1_lr_reg,
+ SPR_EX_CONTEXT_0_0);
+ }
+ if (y1_br) {
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_mtspr(SPR_EX_CONTEXT_0_0,
+ clob2);
+ }
+ if (x1_add) {
+ frag.insn[n++] =
+ jit_x0_addi(ra, ra, x1_add_imm8) |
+ jit_x1_ld_add(clob2, clob3, -8);
+ } else {
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ld_add(clob2, clob3, -8);
+ }
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ld_add(clob1, clob3, -8);
+ frag.insn[n++] = jit_x0_fnop() | jit_x1_ld(clob3, clob3);
+ frag.insn[n++] = jit_x0_fnop() | jit_x1_iret();
+
+ } else {
+ /*
+ * Generic memory load cases.
+ *
+ * Alloc space for saveing clob1,2,3 on user's stack.
+ * register clob3 points to where clob1 saved, followed
+ * by clob2 and 3 from high to low memory.
+ */
+
+ frag.insn[n++] =
+ jit_x0_addi(TREG_SP, TREG_SP, -32) |
+ jit_x1_fnop();
+ frag.insn[n++] =
+ jit_x0_addi(clob3, TREG_SP, 16) |
+ jit_x1_st_add(TREG_SP, clob3, 8);
+ frag.insn[n++] =
+ jit_x0_addi(clob2, ra, 0) |
+ jit_x1_st_add(TREG_SP, clob2, 8);
+
+ if (y1_br) {
+ frag.insn[n++] =
+ jit_x0_addi(clob1, y1_br_reg, 0) |
+ jit_x1_st_add(TREG_SP, clob1, 16);
+ } else {
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_st_add(TREG_SP, clob1, 16);
+ }
+
+ if (bundle_2_enable)
+ frag.insn[n++] = bundle_2;
+
+ if (y1_lr) {
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_mfspr(y1_lr_reg,
+ SPR_EX_CONTEXT_0_0);
+ }
+
+ if (y1_br) {
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_mtspr(SPR_EX_CONTEXT_0_0,
+ clob1);
+ }
+
+ frag.insn[n++] =
+ jit_x0_addi(clob1, clob2, 7) |
+ jit_x1_ldna(rd, clob2);
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ldna(clob1, clob1);
+ frag.insn[n++] =
+ jit_x0_dblalign(rd, clob1, clob2) |
+ jit_x1_ld_add(clob1, clob3, -8);
+ if (x1_add) {
+ frag.insn[n++] =
+ jit_x0_addi(ra, ra, x1_add_imm8) |
+ jit_x1_ld_add(clob2, clob3, -8);
+ } else {
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ld_add(clob2, clob3, -8);
+ }
+
+ frag.insn[n++] =
+ jit_x0_fnop() |
+ jit_x1_ld(clob3, clob3);
+
+ if (load_store_size == 4) {
+ if (load_store_signed)
+ frag.insn[n++] =
+ jit_x0_bfexts(
+ rd, rd,
+ UA_FIXUP_BFEXT_START(4),
+ UA_FIXUP_BFEXT_END(4)) |
+ jit_x1_fnop();
+ else
+ frag.insn[n++] =
+ jit_x0_bfextu(
+ rd, rd,
+ UA_FIXUP_BFEXT_START(4),
+ UA_FIXUP_BFEXT_END(4)) |
+ jit_x1_fnop();
+ } else if (load_store_size == 2) {
+ if (load_store_signed)
+ frag.insn[n++] =
+ jit_x0_bfexts(
+ rd, rd,
+ UA_FIXUP_BFEXT_START(2),
+ UA_FIXUP_BFEXT_END(2)) |
+ jit_x1_fnop();
+ else
+ frag.insn[n++] =
+ jit_x0_bfextu(
+ rd, rd,
+ UA_FIXUP_BFEXT_START(2),
+ UA_FIXUP_BFEXT_END(2)) |
+ jit_x1_fnop();
+ }
+
+ frag.insn[n++] = jit_x0_fnop() | jit_x1_iret();
+ }
+
+ /* Max JIT bundle count is 14. */
+ WARN_ON(n > 14);
+
+ if (!unexpected) {
+ int status = 0;
+ int idx = (regs->pc >> 3) &
+ ((1ULL << (PAGE_SHIFT - UNALIGN_JIT_SHIFT)) - 1);
+
+ frag.pc = regs->pc;
+ frag.bundle = bundle;
+
+ if (unaligned_printk) {
+ pr_info("%s/%d, Unalign fixup: pc=%lx bundle=%lx %d %d %d %d %d %d %d %d\n",
+ current->comm, current->pid,
+ (unsigned long)frag.pc,
+ (unsigned long)frag.bundle,
+ (int)alias, (int)rd, (int)ra,
+ (int)rb, (int)bundle_2_enable,
+ (int)y1_lr, (int)y1_br, (int)x1_add);
+
+ for (k = 0; k < n; k += 2)
+ pr_info("[%d] %016llx %016llx\n",
+ k, (unsigned long long)frag.insn[k],
+ (unsigned long long)frag.insn[k+1]);
+ }
+
+ /* Swap bundle byte order for big endian sys. */
+#ifdef __BIG_ENDIAN
+ frag.bundle = GX_INSN_BSWAP(frag.bundle);
+ for (k = 0; k < n; k++)
+ frag.insn[k] = GX_INSN_BSWAP(frag.insn[k]);
+#endif /* __BIG_ENDIAN */
+
+ status = copy_to_user((void __user *)&jit_code_area[idx],
+ &frag, sizeof(frag));
+ if (status) {
+ /* Fail to copy JIT into user land. send SIGSEGV. */
+ siginfo_t info = {
+ .si_signo = SIGSEGV,
+ .si_code = SEGV_MAPERR,
+ .si_addr = (void __user *)&jit_code_area[idx]
+ };
+
+ pr_warn("Unalign fixup: pid=%d %s jit_code_area=%llx\n",
+ current->pid, current->comm,
+ (unsigned long long)&jit_code_area[idx]);
+
+ trace_unhandled_signal("segfault in unalign fixup",
+ regs,
+ (unsigned long)info.si_addr,
+ SIGSEGV);
+ force_sig_info(info.si_signo, &info, current);
+ return;
+ }
+
+
+ /* Do a cheaper increment, not accurate. */
+ unaligned_fixup_count++;
+ __flush_icache_range((unsigned long)&jit_code_area[idx],
+ (unsigned long)&jit_code_area[idx] +
+ sizeof(frag));
+
+ /* Setup SPR_EX_CONTEXT_0_0/1 for returning to user program.*/
+ __insn_mtspr(SPR_EX_CONTEXT_0_0, regs->pc + 8);
+ __insn_mtspr(SPR_EX_CONTEXT_0_1, PL_ICS_EX1(USER_PL, 0));
+
+ /* Modify pc at the start of new JIT. */
+ regs->pc = (unsigned long)&jit_code_area[idx].insn[0];
+ /* Set ICS in SPR_EX_CONTEXT_K_1. */
+ regs->ex1 = PL_ICS_EX1(USER_PL, 1);
+ }
+}
+
+
+/*
+ * C function to generate unalign data JIT. Called from unalign data
+ * interrupt handler.
+ *
+ * First check if unalign fix is disabled or exception did not not come from
+ * user space or sp register points to unalign address, if true, generate a
+ * SIGBUS. Then map a page into user space as JIT area if it is not mapped
+ * yet. Genenerate JIT code by calling jit_bundle_gen(). After that return
+ * back to exception handler.
+ *
+ * The exception handler will "iret" to new generated JIT code after
+ * restoring caller saved registers. In theory, the JIT code will perform
+ * another "iret" to resume user's program.
+ */
+
+void do_unaligned(struct pt_regs *regs, int vecnum)
+{
+ enum ctx_state prev_state = exception_enter();
+ tilegx_bundle_bits __user *pc;
+ tilegx_bundle_bits bundle;
+ struct thread_info *info = current_thread_info();
+ int align_ctl;
+
+ /* Checks the per-process unaligned JIT flags */
+ align_ctl = unaligned_fixup;
+ switch (task_thread_info(current)->align_ctl) {
+ case PR_UNALIGN_NOPRINT:
+ align_ctl = 1;
+ break;
+ case PR_UNALIGN_SIGBUS:
+ align_ctl = 0;
+ break;
+ }
+
+ /* Enable iterrupt in order to access user land. */
+ local_irq_enable();
+
+ /*
+ * The fault came from kernel space. Two choices:
+ * (a) unaligned_fixup < 1, we will first call get/put_user fixup
+ * to return -EFAULT. If no fixup, simply panic the kernel.
+ * (b) unaligned_fixup >=1, we will try to fix the unaligned access
+ * if it was triggered by get_user/put_user() macros. Panic the
+ * kernel if it is not fixable.
+ */
+
+ if (EX1_PL(regs->ex1) != USER_PL) {
+
+ if (align_ctl < 1) {
+ unaligned_fixup_count++;
+ /* If exception came from kernel, try fix it up. */
+ if (fixup_exception(regs)) {
+ if (unaligned_printk)
+ pr_info("Unalign fixup: %d %llx @%llx\n",
+ (int)unaligned_fixup,
+ (unsigned long long)regs->ex1,
+ (unsigned long long)regs->pc);
+ } else {
+ /* Not fixable. Go panic. */
+ panic("Unalign exception in Kernel. pc=%lx",
+ regs->pc);
+ }
+ } else {
+ /*
+ * Try to fix the exception. If we can't, panic the
+ * kernel.
+ */
+ bundle = GX_INSN_BSWAP(
+ *((tilegx_bundle_bits *)(regs->pc)));
+ jit_bundle_gen(regs, bundle, align_ctl);
+ }
+ goto done;
+ }
+
+ /*
+ * Fault came from user with ICS or stack is not aligned.
+ * If so, we will trigger SIGBUS.
+ */
+ if ((regs->sp & 0x7) || (regs->ex1) || (align_ctl < 0)) {
+ siginfo_t info = {
+ .si_signo = SIGBUS,
+ .si_code = BUS_ADRALN,
+ .si_addr = (unsigned char __user *)0
+ };
+
+ if (unaligned_printk)
+ pr_info("Unalign fixup: %d %llx @%llx\n",
+ (int)unaligned_fixup,
+ (unsigned long long)regs->ex1,
+ (unsigned long long)regs->pc);
+
+ unaligned_fixup_count++;
+
+ trace_unhandled_signal("unaligned fixup trap", regs, 0, SIGBUS);
+ force_sig_info(info.si_signo, &info, current);
+ goto done;
+ }
+
+
+ /* Read the bundle casued the exception! */
+ pc = (tilegx_bundle_bits __user *)(regs->pc);
+ if (get_user(bundle, pc) != 0) {
+ /* Probably never be here since pc is valid user address.*/
+ siginfo_t info = {
+ .si_signo = SIGSEGV,
+ .si_code = SEGV_MAPERR,
+ .si_addr = (void __user *)pc
+ };
+ pr_err("Couldn't read instruction at %p trying to step\n", pc);
+ trace_unhandled_signal("segfault in unalign fixup", regs,
+ (unsigned long)info.si_addr, SIGSEGV);
+ force_sig_info(info.si_signo, &info, current);
+ goto done;
+ }
+
+ if (!info->unalign_jit_base) {
+ void __user *user_page;
+
+ /*
+ * Allocate a page in userland.
+ * For 64-bit processes we try to place the mapping far
+ * from anything else that might be going on (specifically
+ * 64 GB below the top of the user address space). If it
+ * happens not to be possible to put it there, it's OK;
+ * the kernel will choose another location and we'll
+ * remember it for later.
+ */
+ if (is_compat_task())
+ user_page = NULL;
+ else
+ user_page = (void __user *)(TASK_SIZE - (1UL << 36)) +
+ (current->pid << PAGE_SHIFT);
+
+ user_page = (void __user *) vm_mmap(NULL,
+ (unsigned long)user_page,
+ PAGE_SIZE,
+ PROT_EXEC | PROT_READ |
+ PROT_WRITE,
+#ifdef CONFIG_HOMECACHE
+ MAP_CACHE_HOME_TASK |
+#endif
+ MAP_PRIVATE |
+ MAP_ANONYMOUS,
+ 0);
+
+ if (IS_ERR((void __force *)user_page)) {
+ pr_err("Out of kernel pages trying do_mmap\n");
+ goto done;
+ }
+
+ /* Save the address in the thread_info struct */
+ info->unalign_jit_base = user_page;
+ if (unaligned_printk)
+ pr_info("Unalign bundle: %d:%d, allocate page @%llx\n",
+ raw_smp_processor_id(), current->pid,
+ (unsigned long long)user_page);
+ }
+
+ /* Generate unalign JIT */
+ jit_bundle_gen(regs, GX_INSN_BSWAP(bundle), align_ctl);
+
+done:
+ exception_exit(prev_state);
+}
+
+#endif /* __tilegx__ */
Code Review / kvmfornfv.git / blobdiff