| /* SPDX-License-Identifier: GPL-2.0-only */ |
| /* |
| * Copyright (C) 2020 - Google Inc |
| * Author: Andrew Scull <ascull@google.com> |
| */ |
| |
| #include <linux/linkage.h> |
| |
| #include <asm/assembler.h> |
| #include <asm/kvm_arm.h> |
| #include <asm/kvm_asm.h> |
| #include <asm/kvm_mmu.h> |
| |
| .text |
| |
| SYM_FUNC_START(__host_exit) |
| get_host_ctxt x0, x1 |
| |
| /* Store the host regs x2 and x3 */ |
| stp x2, x3, [x0, #CPU_XREG_OFFSET(2)] |
| |
| /* Retrieve the host regs x0-x1 from the stack */ |
| ldp x2, x3, [sp], #16 // x0, x1 |
| |
| /* Store the host regs x0-x1 and x4-x17 */ |
| stp x2, x3, [x0, #CPU_XREG_OFFSET(0)] |
| stp x4, x5, [x0, #CPU_XREG_OFFSET(4)] |
| stp x6, x7, [x0, #CPU_XREG_OFFSET(6)] |
| stp x8, x9, [x0, #CPU_XREG_OFFSET(8)] |
| stp x10, x11, [x0, #CPU_XREG_OFFSET(10)] |
| stp x12, x13, [x0, #CPU_XREG_OFFSET(12)] |
| stp x14, x15, [x0, #CPU_XREG_OFFSET(14)] |
| stp x16, x17, [x0, #CPU_XREG_OFFSET(16)] |
| |
| /* Store the host regs x18-x29, lr */ |
| save_callee_saved_regs x0 |
| |
| /* Save the host context pointer in x29 across the function call */ |
| mov x29, x0 |
| bl handle_trap |
| |
| /* Restore host regs x0-x17 */ |
| __host_enter_restore_full: |
| ldp x0, x1, [x29, #CPU_XREG_OFFSET(0)] |
| ldp x2, x3, [x29, #CPU_XREG_OFFSET(2)] |
| ldp x4, x5, [x29, #CPU_XREG_OFFSET(4)] |
| ldp x6, x7, [x29, #CPU_XREG_OFFSET(6)] |
| |
| /* x0-7 are use for panic arguments */ |
| __host_enter_for_panic: |
| ldp x8, x9, [x29, #CPU_XREG_OFFSET(8)] |
| ldp x10, x11, [x29, #CPU_XREG_OFFSET(10)] |
| ldp x12, x13, [x29, #CPU_XREG_OFFSET(12)] |
| ldp x14, x15, [x29, #CPU_XREG_OFFSET(14)] |
| ldp x16, x17, [x29, #CPU_XREG_OFFSET(16)] |
| |
| /* Restore host regs x18-x29, lr */ |
| restore_callee_saved_regs x29 |
| |
| /* Do not touch any register after this! */ |
| __host_enter_without_restoring: |
| eret |
| sb |
| SYM_FUNC_END(__host_exit) |
| |
| /* |
| * void __noreturn __host_enter(struct kvm_cpu_context *host_ctxt); |
| */ |
| SYM_FUNC_START(__host_enter) |
| mov x29, x0 |
| b __host_enter_restore_full |
| SYM_FUNC_END(__host_enter) |
| |
| /* |
| * void __noreturn __hyp_do_panic(struct kvm_cpu_context *host_ctxt, u64 spsr, |
| * u64 elr, u64 par); |
| */ |
| SYM_FUNC_START(__hyp_do_panic) |
| /* Prepare and exit to the host's panic funciton. */ |
| mov lr, #(PSR_F_BIT | PSR_I_BIT | PSR_A_BIT | PSR_D_BIT |\ |
| PSR_MODE_EL1h) |
| msr spsr_el2, lr |
| ldr lr, =nvhe_hyp_panic_handler |
| hyp_kimg_va lr, x6 |
| msr elr_el2, lr |
| |
| mov x29, x0 |
| |
| #ifdef CONFIG_NVHE_EL2_DEBUG |
| /* Ensure host stage-2 is disabled */ |
| mrs x0, hcr_el2 |
| bic x0, x0, #HCR_VM |
| msr hcr_el2, x0 |
| isb |
| tlbi vmalls12e1 |
| dsb nsh |
| #endif |
| |
| /* Load the panic arguments into x0-7 */ |
| mrs x0, esr_el2 |
| mov x4, x3 |
| mov x3, x2 |
| hyp_pa x3, x6 |
| get_vcpu_ptr x5, x6 |
| mrs x6, far_el2 |
| mrs x7, hpfar_el2 |
| |
| /* Enter the host, conditionally restoring the host context. */ |
| cbz x29, __host_enter_without_restoring |
| b __host_enter_for_panic |
| SYM_FUNC_END(__hyp_do_panic) |
| |
| .macro host_el1_sync_vect |
| .align 7 |
| .L__vect_start\@: |
| stp x0, x1, [sp, #-16]! |
| mrs x0, esr_el2 |
| lsr x0, x0, #ESR_ELx_EC_SHIFT |
| cmp x0, #ESR_ELx_EC_HVC64 |
| b.ne __host_exit |
| |
| ldp x0, x1, [sp] // Don't fixup the stack yet |
| |
| /* Check for a stub HVC call */ |
| cmp x0, #HVC_STUB_HCALL_NR |
| b.hs __host_exit |
| |
| add sp, sp, #16 |
| /* |
| * Compute the idmap address of __kvm_handle_stub_hvc and |
| * jump there. Since we use kimage_voffset, do not use the |
| * HYP VA for __kvm_handle_stub_hvc, but the kernel VA instead |
| * (by loading it from the constant pool). |
| * |
| * Preserve x0-x4, which may contain stub parameters. |
| */ |
| ldr x5, =__kvm_handle_stub_hvc |
| hyp_pa x5, x6 |
| br x5 |
| .L__vect_end\@: |
| .if ((.L__vect_end\@ - .L__vect_start\@) > 0x80) |
| .error "host_el1_sync_vect larger than vector entry" |
| .endif |
| .endm |
| |
| .macro invalid_host_el2_vect |
| .align 7 |
| /* If a guest is loaded, panic out of it. */ |
| stp x0, x1, [sp, #-16]! |
| get_loaded_vcpu x0, x1 |
| cbnz x0, __guest_exit_panic |
| add sp, sp, #16 |
| |
| /* |
| * The panic may not be clean if the exception is taken before the host |
| * context has been saved by __host_exit or after the hyp context has |
| * been partially clobbered by __host_enter. |
| */ |
| b hyp_panic |
| .endm |
| |
| .macro invalid_host_el1_vect |
| .align 7 |
| mov x0, xzr /* restore_host = false */ |
| mrs x1, spsr_el2 |
| mrs x2, elr_el2 |
| mrs x3, par_el1 |
| b __hyp_do_panic |
| .endm |
| |
| /* |
| * The host vector does not use an ESB instruction in order to avoid consuming |
| * SErrors that should only be consumed by the host. Guest entry is deferred by |
| * __guest_enter if there are any pending asynchronous exceptions so hyp will |
| * always return to the host without having consumerd host SErrors. |
| * |
| * CONFIG_KVM_INDIRECT_VECTORS is not applied to the host vectors because the |
| * host knows about the EL2 vectors already, and there is no point in hiding |
| * them. |
| */ |
| .align 11 |
| SYM_CODE_START(__kvm_hyp_host_vector) |
| invalid_host_el2_vect // Synchronous EL2t |
| invalid_host_el2_vect // IRQ EL2t |
| invalid_host_el2_vect // FIQ EL2t |
| invalid_host_el2_vect // Error EL2t |
| |
| invalid_host_el2_vect // Synchronous EL2h |
| invalid_host_el2_vect // IRQ EL2h |
| invalid_host_el2_vect // FIQ EL2h |
| invalid_host_el2_vect // Error EL2h |
| |
| host_el1_sync_vect // Synchronous 64-bit EL1 |
| invalid_host_el1_vect // IRQ 64-bit EL1 |
| invalid_host_el1_vect // FIQ 64-bit EL1 |
| invalid_host_el1_vect // Error 64-bit EL1 |
| |
| invalid_host_el1_vect // Synchronous 32-bit EL1 |
| invalid_host_el1_vect // IRQ 32-bit EL1 |
| invalid_host_el1_vect // FIQ 32-bit EL1 |
| invalid_host_el1_vect // Error 32-bit EL1 |
| SYM_CODE_END(__kvm_hyp_host_vector) |
| |
| /* |
| * Forward SMC with arguments in struct kvm_cpu_context, and |
| * store the result into the same struct. Assumes SMCCC 1.2 or older. |
| * |
| * x0: struct kvm_cpu_context* |
| */ |
| SYM_CODE_START(__kvm_hyp_host_forward_smc) |
| /* |
| * Use x18 to keep the pointer to the host context because |
| * x18 is callee-saved in SMCCC but not in AAPCS64. |
| */ |
| mov x18, x0 |
| |
| ldp x0, x1, [x18, #CPU_XREG_OFFSET(0)] |
| ldp x2, x3, [x18, #CPU_XREG_OFFSET(2)] |
| ldp x4, x5, [x18, #CPU_XREG_OFFSET(4)] |
| ldp x6, x7, [x18, #CPU_XREG_OFFSET(6)] |
| ldp x8, x9, [x18, #CPU_XREG_OFFSET(8)] |
| ldp x10, x11, [x18, #CPU_XREG_OFFSET(10)] |
| ldp x12, x13, [x18, #CPU_XREG_OFFSET(12)] |
| ldp x14, x15, [x18, #CPU_XREG_OFFSET(14)] |
| ldp x16, x17, [x18, #CPU_XREG_OFFSET(16)] |
| |
| smc #0 |
| |
| stp x0, x1, [x18, #CPU_XREG_OFFSET(0)] |
| stp x2, x3, [x18, #CPU_XREG_OFFSET(2)] |
| stp x4, x5, [x18, #CPU_XREG_OFFSET(4)] |
| stp x6, x7, [x18, #CPU_XREG_OFFSET(6)] |
| stp x8, x9, [x18, #CPU_XREG_OFFSET(8)] |
| stp x10, x11, [x18, #CPU_XREG_OFFSET(10)] |
| stp x12, x13, [x18, #CPU_XREG_OFFSET(12)] |
| stp x14, x15, [x18, #CPU_XREG_OFFSET(14)] |
| stp x16, x17, [x18, #CPU_XREG_OFFSET(16)] |
| |
| ret |
| SYM_CODE_END(__kvm_hyp_host_forward_smc) |
