arm64: KVM: split GICv2 world switch from hyp code

Move the GICv2 world switch code into its own file, and add the
necessary indirection to the arm64 switch code.

Also introduce a new type field to the vgic_params structure.

Acked-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

6 files changed, 180 insertions, 89 deletions

diff --git a/arch/arm64/include/asm/kvm_asm.h b/arch/arm64/include/asm/kvm_asm.h
index d0bfc4ba82c0..6252264341c8 100644
--- a/arch/arm64/include/asm/kvm_asm.h
+++ b/arch/arm64/include/asm/kvm_asm.h
@@ -105,6 +105,10 @@ extern void __kvm_flush_vm_context(void);
 extern void __kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa);
 
 extern int __kvm_vcpu_run(struct kvm_vcpu *vcpu);
+
+extern char __save_vgic_v2_state[];
+extern char __restore_vgic_v2_state[];
+
 #endif
 
 #endif /* __ARM_KVM_ASM_H__ */
diff --git a/arch/arm64/include/asm/kvm_host.h b/arch/arm64/include/asm/kvm_host.h
index 92242ce06309..4c182d0aae70 100644
--- a/arch/arm64/include/asm/kvm_host.h
+++ b/arch/arm64/include/asm/kvm_host.h
@@ -200,4 +200,25 @@ static inline void __cpu_init_hyp_mode(phys_addr_t boot_pgd_ptr,
                      hyp_stack_ptr, vector_ptr);
 }
 
+struct vgic_sr_vectors {
+        void    *save_vgic;
+        void    *restore_vgic;
+};
+
+static inline void vgic_arch_setup(const struct vgic_params *vgic)
+{
+        extern struct vgic_sr_vectors __vgic_sr_vectors;
+
+        switch(vgic->type)
+        {
+        case VGIC_V2:
+                __vgic_sr_vectors.save_vgic     = __save_vgic_v2_state;
+                __vgic_sr_vectors.restore_vgic  = __restore_vgic_v2_state;
+                break;
+
+        default:
+                BUG();
+        }
+}
+
 #endif /* __ARM64_KVM_HOST_H__ */
diff --git a/arch/arm64/kernel/asm-offsets.c b/arch/arm64/kernel/asm-offsets.c
index 20fd4887aab6..dafc415dd52d 100644
--- a/arch/arm64/kernel/asm-offsets.c
+++ b/arch/arm64/kernel/asm-offsets.c
@@ -129,6 +129,9 @@ int main(void)
   DEFINE(KVM_TIMER_ENABLED,     offsetof(struct kvm, arch.timer.enabled));
   DEFINE(VCPU_KVM,              offsetof(struct kvm_vcpu, kvm));
   DEFINE(VCPU_VGIC_CPU,         offsetof(struct kvm_vcpu, arch.vgic_cpu));
+  DEFINE(VGIC_SAVE_FN,          offsetof(struct vgic_sr_vectors, save_vgic));
+  DEFINE(VGIC_RESTORE_FN,       offsetof(struct vgic_sr_vectors, restore_vgic));
+  DEFINE(VGIC_SR_VECTOR_SZ,     sizeof(struct vgic_sr_vectors));
   DEFINE(VGIC_V2_CPU_HCR,       offsetof(struct vgic_cpu, vgic_v2.vgic_hcr));
   DEFINE(VGIC_V2_CPU_VMCR,      offsetof(struct vgic_cpu, vgic_v2.vgic_vmcr));
   DEFINE(VGIC_V2_CPU_MISR,      offsetof(struct vgic_cpu, vgic_v2.vgic_misr));
diff --git a/arch/arm64/kvm/Makefile b/arch/arm64/kvm/Makefile
index 7e92952d139e..daf24dc59e2c 100644
--- a/arch/arm64/kvm/Makefile
+++ b/arch/arm64/kvm/Makefile
@@ -19,5 +19,7 @@ kvm-$(CONFIG_KVM_ARM_HOST) += emulate.o inject_fault.o regmap.o
 kvm-$(CONFIG_KVM_ARM_HOST) += hyp.o hyp-init.o handle_exit.o
 kvm-$(CONFIG_KVM_ARM_HOST) += guest.o reset.o sys_regs.o sys_regs_generic_v8.o
 
-kvm-$(CONFIG_KVM_ARM_VGIC) += $(KVM)/arm/vgic.o $(KVM)/arm/vgic-v2.o
+kvm-$(CONFIG_KVM_ARM_VGIC) += $(KVM)/arm/vgic.o
+kvm-$(CONFIG_KVM_ARM_VGIC) += $(KVM)/arm/vgic-v2.o
+kvm-$(CONFIG_KVM_ARM_VGIC) += vgic-v2-switch.o
 kvm-$(CONFIG_KVM_ARM_TIMER) += $(KVM)/arm/arch_timer.o
diff --git a/arch/arm64/kvm/hyp.S b/arch/arm64/kvm/hyp.S
index 9c5d0acb3654..56df9a352a81 100644
--- a/arch/arm64/kvm/hyp.S
+++ b/arch/arm64/kvm/hyp.S
@@ -16,7 +16,6 @@
  */
 
 #include <linux/linkage.h>
-#include <linux/irqchip/arm-gic.h>
 
 #include <asm/assembler.h>
 #include <asm/memory.h>
@@ -376,100 +375,23 @@
 .endm
 
 /*
- * Save the VGIC CPU state into memory
- * x0: Register pointing to VCPU struct
- * Do not corrupt x1!!!
+ * Call into the vgic backend for state saving
  */
 .macro save_vgic_state
-        /* Get VGIC VCTRL base into x2 */
-        ldr     x2, [x0, #VCPU_KVM]
-        kern_hyp_va     x2
-        ldr     x2, [x2, #KVM_VGIC_VCTRL]
-        kern_hyp_va     x2
-        cbz     x2, 2f          // disabled
-
-        /* Compute the address of struct vgic_cpu */
-        add     x3, x0, #VCPU_VGIC_CPU
-
-        /* Save all interesting registers */
-        ldr     w4, [x2, #GICH_HCR]
-        ldr     w5, [x2, #GICH_VMCR]
-        ldr     w6, [x2, #GICH_MISR]
-        ldr     w7, [x2, #GICH_EISR0]
-        ldr     w8, [x2, #GICH_EISR1]
-        ldr     w9, [x2, #GICH_ELRSR0]
-        ldr     w10, [x2, #GICH_ELRSR1]
-        ldr     w11, [x2, #GICH_APR]
-CPU_BE( rev     w4,  w4  )
-CPU_BE( rev     w5,  w5  )
-CPU_BE( rev     w6,  w6  )
-CPU_BE( rev     w7,  w7  )
-CPU_BE( rev     w8,  w8  )
-CPU_BE( rev     w9,  w9  )
-CPU_BE( rev     w10, w10 )
-CPU_BE( rev     w11, w11 )
-
-        str     w4, [x3, #VGIC_V2_CPU_HCR]
-        str     w5, [x3, #VGIC_V2_CPU_VMCR]
-        str     w6, [x3, #VGIC_V2_CPU_MISR]
-        str     w7, [x3, #VGIC_V2_CPU_EISR]
-        str     w8, [x3, #(VGIC_V2_CPU_EISR + 4)]
-        str     w9, [x3, #VGIC_V2_CPU_ELRSR]
-        str     w10, [x3, #(VGIC_V2_CPU_ELRSR + 4)]
-        str     w11, [x3, #VGIC_V2_CPU_APR]
-
-        /* Clear GICH_HCR */
-        str     wzr, [x2, #GICH_HCR]
-
-        /* Save list registers */
-        add     x2, x2, #GICH_LR0
-        ldr     w4, [x3, #VGIC_CPU_NR_LR]
-        add     x3, x3, #VGIC_V2_CPU_LR
-1:      ldr     w5, [x2], #4
-CPU_BE( rev     w5, w5 )
-        str     w5, [x3], #4
-        sub     w4, w4, #1
-        cbnz    w4, 1b
-2:
+        adr     x24, __vgic_sr_vectors
+        ldr     x24, [x24, VGIC_SAVE_FN]
+        kern_hyp_va     x24
+        blr     x24
 .endm
 
 /*
- * Restore the VGIC CPU state from memory
- * x0: Register pointing to VCPU struct
+ * Call into the vgic backend for state restoring
  */
 .macro restore_vgic_state
-        /* Get VGIC VCTRL base into x2 */
-        ldr     x2, [x0, #VCPU_KVM]
-        kern_hyp_va     x2
-        ldr     x2, [x2, #KVM_VGIC_VCTRL]
-        kern_hyp_va     x2
-        cbz     x2, 2f          // disabled
-
-        /* Compute the address of struct vgic_cpu */
-        add     x3, x0, #VCPU_VGIC_CPU
-
-        /* We only restore a minimal set of registers */
-        ldr     w4, [x3, #VGIC_V2_CPU_HCR]
-        ldr     w5, [x3, #VGIC_V2_CPU_VMCR]
-        ldr     w6, [x3, #VGIC_V2_CPU_APR]
-CPU_BE( rev     w4, w4 )
-CPU_BE( rev     w5, w5 )
-CPU_BE( rev     w6, w6 )
-
-        str     w4, [x2, #GICH_HCR]
-        str     w5, [x2, #GICH_VMCR]
-        str     w6, [x2, #GICH_APR]
-
-        /* Restore list registers */
-        add     x2, x2, #GICH_LR0
-        ldr     w4, [x3, #VGIC_CPU_NR_LR]
-        add     x3, x3, #VGIC_V2_CPU_LR
-1:      ldr     w5, [x3], #4
-CPU_BE( rev     w5, w5 )
-        str     w5, [x2], #4
-        sub     w4, w4, #1
-        cbnz    w4, 1b
-2:
+        adr     x24, __vgic_sr_vectors
+        ldr     x24, [x24, #VGIC_RESTORE_FN]
+        kern_hyp_va     x24
+        blr     x24
 .endm
 
 .macro save_timer_state
@@ -650,6 +572,12 @@ ENTRY(__kvm_flush_vm_context)
         ret
 ENDPROC(__kvm_flush_vm_context)
 
+        // struct vgic_sr_vectors __vgi_sr_vectors;
+        .align 3
+ENTRY(__vgic_sr_vectors)
+        .skip   VGIC_SR_VECTOR_SZ
+ENDPROC(__vgic_sr_vectors)
+
 __kvm_hyp_panic:
         // Guess the context by looking at VTTBR:
         // If zero, then we're already a host.
diff --git a/arch/arm64/kvm/vgic-v2-switch.S b/arch/arm64/kvm/vgic-v2-switch.S
new file mode 100644
index 000000000000..ae211772f991
--- /dev/null
+++ b/arch/arm64/kvm/vgic-v2-switch.S
@@ -0,0 +1,133 @@
+/*
+ * Copyright (C) 2012,2013 - ARM Ltd
+ * Author: Marc Zyngier <marc.zyngier@arm.com>
+ *
+ * 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/irqchip/arm-gic.h>
+
+#include <asm/assembler.h>
+#include <asm/memory.h>
+#include <asm/asm-offsets.h>
+#include <asm/kvm.h>
+#include <asm/kvm_asm.h>
+#include <asm/kvm_arm.h>
+#include <asm/kvm_mmu.h>
+
+        .text
+        .pushsection    .hyp.text, "ax"
+
+/*
+ * Save the VGIC CPU state into memory
+ * x0: Register pointing to VCPU struct
+ * Do not corrupt x1!!!
+ */
+ENTRY(__save_vgic_v2_state)
+__save_vgic_v2_state:
+        /* Get VGIC VCTRL base into x2 */
+        ldr     x2, [x0, #VCPU_KVM]
+        kern_hyp_va     x2
+        ldr     x2, [x2, #KVM_VGIC_VCTRL]
+        kern_hyp_va     x2
+        cbz     x2, 2f          // disabled
+
+        /* Compute the address of struct vgic_cpu */
+        add     x3, x0, #VCPU_VGIC_CPU
+
+        /* Save all interesting registers */
+        ldr     w4, [x2, #GICH_HCR]
+        ldr     w5, [x2, #GICH_VMCR]
+        ldr     w6, [x2, #GICH_MISR]
+        ldr     w7, [x2, #GICH_EISR0]
+        ldr     w8, [x2, #GICH_EISR1]
+        ldr     w9, [x2, #GICH_ELRSR0]
+        ldr     w10, [x2, #GICH_ELRSR1]
+        ldr     w11, [x2, #GICH_APR]
+CPU_BE( rev     w4,  w4  )
+CPU_BE( rev     w5,  w5  )
+CPU_BE( rev     w6,  w6  )
+CPU_BE( rev     w7,  w7  )
+CPU_BE( rev     w8,  w8  )
+CPU_BE( rev     w9,  w9  )
+CPU_BE( rev     w10, w10 )
+CPU_BE( rev     w11, w11 )
+
+        str     w4, [x3, #VGIC_V2_CPU_HCR]
+        str     w5, [x3, #VGIC_V2_CPU_VMCR]
+        str     w6, [x3, #VGIC_V2_CPU_MISR]
+        str     w7, [x3, #VGIC_V2_CPU_EISR]
+        str     w8, [x3, #(VGIC_V2_CPU_EISR + 4)]
+        str     w9, [x3, #VGIC_V2_CPU_ELRSR]
+        str     w10, [x3, #(VGIC_V2_CPU_ELRSR + 4)]
+        str     w11, [x3, #VGIC_V2_CPU_APR]
+
+        /* Clear GICH_HCR */
+        str     wzr, [x2, #GICH_HCR]
+
+        /* Save list registers */
+        add     x2, x2, #GICH_LR0
+        ldr     w4, [x3, #VGIC_CPU_NR_LR]
+        add     x3, x3, #VGIC_V2_CPU_LR
+1:      ldr     w5, [x2], #4
+CPU_BE( rev     w5, w5 )
+        str     w5, [x3], #4
+        sub     w4, w4, #1
+        cbnz    w4, 1b
+2:
+        ret
+ENDPROC(__save_vgic_v2_state)
+
+/*
+ * Restore the VGIC CPU state from memory
+ * x0: Register pointing to VCPU struct
+ */
+ENTRY(__restore_vgic_v2_state)
+__restore_vgic_v2_state:
+        /* Get VGIC VCTRL base into x2 */
+        ldr     x2, [x0, #VCPU_KVM]
+        kern_hyp_va     x2
+        ldr     x2, [x2, #KVM_VGIC_VCTRL]
+        kern_hyp_va     x2
+        cbz     x2, 2f          // disabled
+
+        /* Compute the address of struct vgic_cpu */
+        add     x3, x0, #VCPU_VGIC_CPU
+
+        /* We only restore a minimal set of registers */
+        ldr     w4, [x3, #VGIC_V2_CPU_HCR]
+        ldr     w5, [x3, #VGIC_V2_CPU_VMCR]
+        ldr     w6, [x3, #VGIC_V2_CPU_APR]
+CPU_BE( rev     w4, w4 )
+CPU_BE( rev     w5, w5 )
+CPU_BE( rev     w6, w6 )
+
+        str     w4, [x2, #GICH_HCR]
+        str     w5, [x2, #GICH_VMCR]
+        str     w6, [x2, #GICH_APR]
+
+        /* Restore list registers */
+        add     x2, x2, #GICH_LR0
+        ldr     w4, [x3, #VGIC_CPU_NR_LR]
+        add     x3, x3, #VGIC_V2_CPU_LR
+1:      ldr     w5, [x3], #4
+CPU_BE( rev     w5, w5 )
+        str     w5, [x2], #4
+        sub     w4, w4, #1
+        cbnz    w4, 1b
+2:
+        ret
+ENDPROC(__restore_vgic_v2_state)
+
+        .popsection