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-rw-r--r--arch/powerpc/kernel/kvm_emul.S354
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diff --git a/arch/powerpc/kernel/kvm_emul.S b/arch/powerpc/kernel/kvm_emul.S
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+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ *
+ * Copyright SUSE Linux Products GmbH 2010
+ * Copyright 2010-2011 Freescale Semiconductor, Inc.
+ *
+ * Authors: Alexander Graf <agraf@suse.de>
+ */
+
+#include <asm/ppc_asm.h>
+#include <asm/kvm_asm.h>
+#include <asm/reg.h>
+#include <asm/page.h>
+#include <asm/asm-offsets.h>
+#include <asm/asm-compat.h>
+
+#define KVM_MAGIC_PAGE (-4096)
+
+#ifdef CONFIG_64BIT
+#define LL64(reg, offs, reg2) ld reg, (offs)(reg2)
+#define STL64(reg, offs, reg2) std reg, (offs)(reg2)
+#else
+#define LL64(reg, offs, reg2) lwz reg, (offs + 4)(reg2)
+#define STL64(reg, offs, reg2) stw reg, (offs + 4)(reg2)
+#endif
+
+#define SCRATCH_SAVE \
+ /* Enable critical section. We are critical if \
+ shared->critical == r1 */ \
+ STL64(r1, KVM_MAGIC_PAGE + KVM_MAGIC_CRITICAL, 0); \
+ \
+ /* Save state */ \
+ PPC_STL r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH1)(0); \
+ PPC_STL r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH2)(0); \
+ mfcr r31; \
+ stw r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH3)(0);
+
+#define SCRATCH_RESTORE \
+ /* Restore state */ \
+ PPC_LL r31, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH1)(0); \
+ lwz r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH3)(0); \
+ mtcr r30; \
+ PPC_LL r30, (KVM_MAGIC_PAGE + KVM_MAGIC_SCRATCH2)(0); \
+ \
+ /* Disable critical section. We are critical if \
+ shared->critical == r1 and r2 is always != r1 */ \
+ STL64(r2, KVM_MAGIC_PAGE + KVM_MAGIC_CRITICAL, 0);
+
+.global kvm_template_start
+kvm_template_start:
+
+.global kvm_emulate_mtmsrd
+kvm_emulate_mtmsrd:
+
+ SCRATCH_SAVE
+
+ /* Put MSR & ~(MSR_EE|MSR_RI) in r31 */
+ LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+ lis r30, (~(MSR_EE | MSR_RI))@h
+ ori r30, r30, (~(MSR_EE | MSR_RI))@l
+ and r31, r31, r30
+
+ /* OR the register's (MSR_EE|MSR_RI) on MSR */
+kvm_emulate_mtmsrd_reg:
+ ori r30, r0, 0
+ andi. r30, r30, (MSR_EE|MSR_RI)
+ or r31, r31, r30
+
+ /* Put MSR back into magic page */
+ STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+ /* Check if we have to fetch an interrupt */
+ lwz r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0)
+ cmpwi r31, 0
+ beq+ no_check
+
+ /* Check if we may trigger an interrupt */
+ andi. r30, r30, MSR_EE
+ beq no_check
+
+ SCRATCH_RESTORE
+
+ /* Nag hypervisor */
+kvm_emulate_mtmsrd_orig_ins:
+ tlbsync
+
+ b kvm_emulate_mtmsrd_branch
+
+no_check:
+
+ SCRATCH_RESTORE
+
+ /* Go back to caller */
+kvm_emulate_mtmsrd_branch:
+ b .
+kvm_emulate_mtmsrd_end:
+
+.global kvm_emulate_mtmsrd_branch_offs
+kvm_emulate_mtmsrd_branch_offs:
+ .long (kvm_emulate_mtmsrd_branch - kvm_emulate_mtmsrd) / 4
+
+.global kvm_emulate_mtmsrd_reg_offs
+kvm_emulate_mtmsrd_reg_offs:
+ .long (kvm_emulate_mtmsrd_reg - kvm_emulate_mtmsrd) / 4
+
+.global kvm_emulate_mtmsrd_orig_ins_offs
+kvm_emulate_mtmsrd_orig_ins_offs:
+ .long (kvm_emulate_mtmsrd_orig_ins - kvm_emulate_mtmsrd) / 4
+
+.global kvm_emulate_mtmsrd_len
+kvm_emulate_mtmsrd_len:
+ .long (kvm_emulate_mtmsrd_end - kvm_emulate_mtmsrd) / 4
+
+
+#define MSR_SAFE_BITS (MSR_EE | MSR_RI)
+#define MSR_CRITICAL_BITS ~MSR_SAFE_BITS
+
+.global kvm_emulate_mtmsr
+kvm_emulate_mtmsr:
+
+ SCRATCH_SAVE
+
+ /* Fetch old MSR in r31 */
+ LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+ /* Find the changed bits between old and new MSR */
+kvm_emulate_mtmsr_reg1:
+ ori r30, r0, 0
+ xor r31, r30, r31
+
+ /* Check if we need to really do mtmsr */
+ LOAD_REG_IMMEDIATE(r30, MSR_CRITICAL_BITS)
+ and. r31, r31, r30
+
+ /* No critical bits changed? Maybe we can stay in the guest. */
+ beq maybe_stay_in_guest
+
+do_mtmsr:
+
+ SCRATCH_RESTORE
+
+ /* Just fire off the mtmsr if it's critical */
+kvm_emulate_mtmsr_orig_ins:
+ mtmsr r0
+
+ b kvm_emulate_mtmsr_branch
+
+maybe_stay_in_guest:
+
+ /* Get the target register in r30 */
+kvm_emulate_mtmsr_reg2:
+ ori r30, r0, 0
+
+ /* Put MSR into magic page because we don't call mtmsr */
+ STL64(r30, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+ /* Check if we have to fetch an interrupt */
+ lwz r31, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0)
+ cmpwi r31, 0
+ beq+ no_mtmsr
+
+ /* Check if we may trigger an interrupt */
+ andi. r31, r30, MSR_EE
+ bne do_mtmsr
+
+no_mtmsr:
+
+ SCRATCH_RESTORE
+
+ /* Go back to caller */
+kvm_emulate_mtmsr_branch:
+ b .
+kvm_emulate_mtmsr_end:
+
+.global kvm_emulate_mtmsr_branch_offs
+kvm_emulate_mtmsr_branch_offs:
+ .long (kvm_emulate_mtmsr_branch - kvm_emulate_mtmsr) / 4
+
+.global kvm_emulate_mtmsr_reg1_offs
+kvm_emulate_mtmsr_reg1_offs:
+ .long (kvm_emulate_mtmsr_reg1 - kvm_emulate_mtmsr) / 4
+
+.global kvm_emulate_mtmsr_reg2_offs
+kvm_emulate_mtmsr_reg2_offs:
+ .long (kvm_emulate_mtmsr_reg2 - kvm_emulate_mtmsr) / 4
+
+.global kvm_emulate_mtmsr_orig_ins_offs
+kvm_emulate_mtmsr_orig_ins_offs:
+ .long (kvm_emulate_mtmsr_orig_ins - kvm_emulate_mtmsr) / 4
+
+.global kvm_emulate_mtmsr_len
+kvm_emulate_mtmsr_len:
+ .long (kvm_emulate_mtmsr_end - kvm_emulate_mtmsr) / 4
+
+#ifdef CONFIG_BOOKE
+
+/* also used for wrteei 1 */
+.global kvm_emulate_wrtee
+kvm_emulate_wrtee:
+
+ SCRATCH_SAVE
+
+ /* Fetch old MSR in r31 */
+ LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+ /* Insert new MSR[EE] */
+kvm_emulate_wrtee_reg:
+ ori r30, r0, 0
+ rlwimi r31, r30, 0, MSR_EE
+
+ /*
+ * If MSR[EE] is now set, check for a pending interrupt.
+ * We could skip this if MSR[EE] was already on, but that
+ * should be rare, so don't bother.
+ */
+ andi. r30, r30, MSR_EE
+
+ /* Put MSR into magic page because we don't call wrtee */
+ STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+ beq no_wrtee
+
+ /* Check if we have to fetch an interrupt */
+ lwz r30, (KVM_MAGIC_PAGE + KVM_MAGIC_INT)(0)
+ cmpwi r30, 0
+ bne do_wrtee
+
+no_wrtee:
+ SCRATCH_RESTORE
+
+ /* Go back to caller */
+kvm_emulate_wrtee_branch:
+ b .
+
+do_wrtee:
+ SCRATCH_RESTORE
+
+ /* Just fire off the wrtee if it's critical */
+kvm_emulate_wrtee_orig_ins:
+ wrtee r0
+
+ b kvm_emulate_wrtee_branch
+
+kvm_emulate_wrtee_end:
+
+.global kvm_emulate_wrtee_branch_offs
+kvm_emulate_wrtee_branch_offs:
+ .long (kvm_emulate_wrtee_branch - kvm_emulate_wrtee) / 4
+
+.global kvm_emulate_wrtee_reg_offs
+kvm_emulate_wrtee_reg_offs:
+ .long (kvm_emulate_wrtee_reg - kvm_emulate_wrtee) / 4
+
+.global kvm_emulate_wrtee_orig_ins_offs
+kvm_emulate_wrtee_orig_ins_offs:
+ .long (kvm_emulate_wrtee_orig_ins - kvm_emulate_wrtee) / 4
+
+.global kvm_emulate_wrtee_len
+kvm_emulate_wrtee_len:
+ .long (kvm_emulate_wrtee_end - kvm_emulate_wrtee) / 4
+
+.global kvm_emulate_wrteei_0
+kvm_emulate_wrteei_0:
+ SCRATCH_SAVE
+
+ /* Fetch old MSR in r31 */
+ LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+ /* Remove MSR_EE from old MSR */
+ rlwinm r31, r31, 0, ~MSR_EE
+
+ /* Write new MSR value back */
+ STL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+
+ SCRATCH_RESTORE
+
+ /* Go back to caller */
+kvm_emulate_wrteei_0_branch:
+ b .
+kvm_emulate_wrteei_0_end:
+
+.global kvm_emulate_wrteei_0_branch_offs
+kvm_emulate_wrteei_0_branch_offs:
+ .long (kvm_emulate_wrteei_0_branch - kvm_emulate_wrteei_0) / 4
+
+.global kvm_emulate_wrteei_0_len
+kvm_emulate_wrteei_0_len:
+ .long (kvm_emulate_wrteei_0_end - kvm_emulate_wrteei_0) / 4
+
+#endif /* CONFIG_BOOKE */
+
+#ifdef CONFIG_PPC_BOOK3S_32
+
+.global kvm_emulate_mtsrin
+kvm_emulate_mtsrin:
+
+ SCRATCH_SAVE
+
+ LL64(r31, KVM_MAGIC_PAGE + KVM_MAGIC_MSR, 0)
+ andi. r31, r31, MSR_DR | MSR_IR
+ beq kvm_emulate_mtsrin_reg1
+
+ SCRATCH_RESTORE
+
+kvm_emulate_mtsrin_orig_ins:
+ nop
+ b kvm_emulate_mtsrin_branch
+
+kvm_emulate_mtsrin_reg1:
+ /* rX >> 26 */
+ rlwinm r30,r0,6,26,29
+
+kvm_emulate_mtsrin_reg2:
+ stw r0, (KVM_MAGIC_PAGE + KVM_MAGIC_SR)(r30)
+
+ SCRATCH_RESTORE
+
+ /* Go back to caller */
+kvm_emulate_mtsrin_branch:
+ b .
+kvm_emulate_mtsrin_end:
+
+.global kvm_emulate_mtsrin_branch_offs
+kvm_emulate_mtsrin_branch_offs:
+ .long (kvm_emulate_mtsrin_branch - kvm_emulate_mtsrin) / 4
+
+.global kvm_emulate_mtsrin_reg1_offs
+kvm_emulate_mtsrin_reg1_offs:
+ .long (kvm_emulate_mtsrin_reg1 - kvm_emulate_mtsrin) / 4
+
+.global kvm_emulate_mtsrin_reg2_offs
+kvm_emulate_mtsrin_reg2_offs:
+ .long (kvm_emulate_mtsrin_reg2 - kvm_emulate_mtsrin) / 4
+
+.global kvm_emulate_mtsrin_orig_ins_offs
+kvm_emulate_mtsrin_orig_ins_offs:
+ .long (kvm_emulate_mtsrin_orig_ins - kvm_emulate_mtsrin) / 4
+
+.global kvm_emulate_mtsrin_len
+kvm_emulate_mtsrin_len:
+ .long (kvm_emulate_mtsrin_end - kvm_emulate_mtsrin) / 4
+
+#endif /* CONFIG_PPC_BOOK3S_32 */
+
+ .balign 4
+ .global kvm_tmp
+kvm_tmp:
+ .space (64 * 1024)
+
+.global kvm_tmp_end
+kvm_tmp_end:
+
+.global kvm_template_end
+kvm_template_end: