arm64: Move the content of bpi.S to hyp-entry.S

bpi.S was introduced as we were starting to build the Spectre v2
mitigation framework, and it was rather unclear that it would
become strictly KVM specific.

Now that the picture is a lot clearer, let's move the content
of that file to hyp-entry.S, where it actually belong.

Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>

arch/arm64/kernel/Makefile

@@ -55,8 +55,6 @@ arm64-reloc-test-y := reloc_test_core.o reloc_test_syms.o
 arm64-obj-$(CONFIG_CRASH_DUMP)		+= crash_dump.o
 arm64-obj-$(CONFIG_ARM_SDE_INTERFACE)	+= sdei.o
 
-arm64-obj-$(CONFIG_KVM_INDIRECT_VECTORS)+= bpi.o
-
 obj-y					+= $(arm64-obj-y) vdso/ probes/
 obj-m					+= $(arm64-obj-m)
 head-y					:= head.o

arch/arm64/kernel/bpi.S

@@ -1,86 +0,0 @@
-/*
- * Contains CPU specific branch predictor invalidation sequences
- *
- * Copyright (C) 2018 ARM Ltd.
- *
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License version 2 as
- * published by the Free Software Foundation.
- *
- * 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, see <http://www.gnu.org/licenses/>.
- */
-
-#include <linux/linkage.h>
-#include <linux/arm-smccc.h>
-
-#include <asm/alternative.h>
-#include <asm/mmu.h>
-
-.macro hyp_ventry
-	.align 7
-1:	.rept 27
-	nop
-	.endr
-/*
- * The default sequence is to directly branch to the KVM vectors,
- * using the computed offset. This applies for VHE as well as
- * !ARM64_HARDEN_EL2_VECTORS.
- *
- * For ARM64_HARDEN_EL2_VECTORS configurations, this gets replaced
- * with:
- *
- * stp	x0, x1, [sp, #-16]!
- * movz	x0, #(addr & 0xffff)
- * movk	x0, #((addr >> 16) & 0xffff), lsl #16
- * movk	x0, #((addr >> 32) & 0xffff), lsl #32
- * br	x0
- *
- * Where addr = kern_hyp_va(__kvm_hyp_vector) + vector-offset + 4.
- * See kvm_patch_vector_branch for details.
- */
-alternative_cb	kvm_patch_vector_branch
-	b	__kvm_hyp_vector + (1b - 0b)
-	nop
-	nop
-	nop
-	nop
-alternative_cb_end
-.endm
-
-.macro generate_vectors
-0:
-	.rept 16
-	hyp_ventry
-	.endr
-	.org 0b + SZ_2K		// Safety measure
-.endm
-
-
-	.text
-	.pushsection	.hyp.text, "ax"
-
-	.align	11
-ENTRY(__bp_harden_hyp_vecs_start)
-	.rept BP_HARDEN_EL2_SLOTS
-	generate_vectors
-	.endr
-ENTRY(__bp_harden_hyp_vecs_end)
-
-	.popsection
-
-ENTRY(__smccc_workaround_1_smc_start)
-	sub	sp, sp, #(8 * 4)
-	stp	x2, x3, [sp, #(8 * 0)]
-	stp	x0, x1, [sp, #(8 * 2)]
-	mov	w0, #ARM_SMCCC_ARCH_WORKAROUND_1
-	smc	#0
-	ldp	x2, x3, [sp, #(8 * 0)]
-	ldp	x0, x1, [sp, #(8 * 2)]
-	add	sp, sp, #(8 * 4)
-ENTRY(__smccc_workaround_1_smc_end)

arch/arm64/kernel/cpu_errata.c

@@ -86,7 +86,7 @@ atomic_t arm64_el2_vector_last_slot = ATOMIC_INIT(-1);
 
 DEFINE_PER_CPU_READ_MOSTLY(struct bp_hardening_data, bp_hardening_data);
 
-#ifdef CONFIG_KVM
+#ifdef CONFIG_KVM_INDIRECT_VECTORS
 extern char __smccc_workaround_1_smc_start[];
 extern char __smccc_workaround_1_smc_end[];
 
@@ -137,7 +137,7 @@ static void __install_bp_hardening_cb(bp_hardening_cb_t fn,
 {
 	__this_cpu_write(bp_hardening_data.fn, fn);
 }
-#endif	/* CONFIG_KVM */
+#endif	/* CONFIG_KVM_INDIRECT_VECTORS */
 
 static void  install_bp_hardening_cb(const struct arm64_cpu_capabilities *entry,
 				     bp_hardening_cb_t fn,

arch/arm64/kvm/hyp/hyp-entry.S

@@ -1,5 +1,5 @@
 /*
- * Copyright (C) 2015 - ARM Ltd
+ * Copyright (C) 2015-2018 - ARM Ltd
  * Author: Marc Zyngier <marc.zyngier@arm.com>
  *
  * This program is free software; you can redistribute it and/or modify
@@ -24,6 +24,7 @@
 #include <asm/kvm_arm.h>
 #include <asm/kvm_asm.h>
 #include <asm/kvm_mmu.h>
+#include <asm/mmu.h>
 
 	.text
 	.pushsection	.hyp.text, "ax"
@@ -237,3 +238,64 @@ ENTRY(__kvm_hyp_vector)
 	invalid_vect	el1_fiq_invalid		// FIQ 32-bit EL1
 	valid_vect	el1_error		// Error 32-bit EL1
 ENDPROC(__kvm_hyp_vector)
+
+#ifdef CONFIG_KVM_INDIRECT_VECTORS
+.macro hyp_ventry
+	.align 7
+1:	.rept 27
+	nop
+	.endr
+/*
+ * The default sequence is to directly branch to the KVM vectors,
+ * using the computed offset. This applies for VHE as well as
+ * !ARM64_HARDEN_EL2_VECTORS.
+ *
+ * For ARM64_HARDEN_EL2_VECTORS configurations, this gets replaced
+ * with:
+ *
+ * stp	x0, x1, [sp, #-16]!
+ * movz	x0, #(addr & 0xffff)
+ * movk	x0, #((addr >> 16) & 0xffff), lsl #16
+ * movk	x0, #((addr >> 32) & 0xffff), lsl #32
+ * br	x0
+ *
+ * Where addr = kern_hyp_va(__kvm_hyp_vector) + vector-offset + 4.
+ * See kvm_patch_vector_branch for details.
+ */
+alternative_cb	kvm_patch_vector_branch
+	b	__kvm_hyp_vector + (1b - 0b)
+	nop
+	nop
+	nop
+	nop
+alternative_cb_end
+.endm
+
+.macro generate_vectors
+0:
+	.rept 16
+	hyp_ventry
+	.endr
+	.org 0b + SZ_2K		// Safety measure
+.endm
+
+	.align	11
+ENTRY(__bp_harden_hyp_vecs_start)
+	.rept BP_HARDEN_EL2_SLOTS
+	generate_vectors
+	.endr
+ENTRY(__bp_harden_hyp_vecs_end)
+
+	.popsection
+
+ENTRY(__smccc_workaround_1_smc_start)
+	sub	sp, sp, #(8 * 4)
+	stp	x2, x3, [sp, #(8 * 0)]
+	stp	x0, x1, [sp, #(8 * 2)]
+	mov	w0, #ARM_SMCCC_ARCH_WORKAROUND_1
+	smc	#0
+	ldp	x2, x3, [sp, #(8 * 0)]
+	ldp	x0, x1, [sp, #(8 * 2)]
+	add	sp, sp, #(8 * 4)
+ENTRY(__smccc_workaround_1_smc_end)
+#endif