diff options
Diffstat (limited to 'arch/arm/kvm')
-rw-r--r-- | arch/arm/kvm/Makefile | 2 | ||||
-rw-r--r-- | arch/arm/kvm/arm.c | 169 | ||||
-rw-r--r-- | arch/arm/kvm/coproc.c | 360 | ||||
-rw-r--r-- | arch/arm/kvm/coproc.h | 153 | ||||
-rw-r--r-- | arch/arm/kvm/coproc_a15.c | 162 | ||||
-rw-r--r-- | arch/arm/kvm/emulate.c | 218 | ||||
-rw-r--r-- | arch/arm/kvm/trace.h | 65 |
7 files changed, 1125 insertions, 4 deletions
diff --git a/arch/arm/kvm/Makefile b/arch/arm/kvm/Makefile index dfc293f..88edce6 100644 --- a/arch/arm/kvm/Makefile +++ b/arch/arm/kvm/Makefile @@ -18,4 +18,4 @@ kvm-arm-y = $(addprefix ../../../virt/kvm/, kvm_main.o coalesced_mmio.o) obj-y += kvm-arm.o init.o interrupts.o obj-y += arm.o guest.o mmu.o emulate.o reset.o -obj-y += coproc.o +obj-y += coproc.o coproc_a15.o diff --git a/arch/arm/kvm/arm.c b/arch/arm/kvm/arm.c index 9e9fa44..be06c5d 100644 --- a/arch/arm/kvm/arm.c +++ b/arch/arm/kvm/arm.c @@ -36,11 +36,14 @@ #include <asm/mman.h> #include <asm/cputype.h> #include <asm/tlbflush.h> +#include <asm/cacheflush.h> #include <asm/virt.h> #include <asm/kvm_arm.h> #include <asm/kvm_asm.h> #include <asm/kvm_mmu.h> #include <asm/kvm_emulate.h> +#include <asm/kvm_coproc.h> +#include <asm/opcodes.h> #ifdef REQUIRES_VIRT __asm__(".arch_extension virt"); @@ -294,6 +297,15 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu) { vcpu->cpu = cpu; vcpu->arch.vfp_host = this_cpu_ptr(kvm_host_vfp_state); + + /* + * Check whether this vcpu requires the cache to be flushed on + * this physical CPU. This is a consequence of doing dcache + * operations by set/way on this vcpu. We do it here to be in + * a non-preemptible section. + */ + if (cpumask_test_and_clear_cpu(cpu, &vcpu->arch.require_dcache_flush)) + flush_cache_all(); /* We'd really want v7_flush_dcache_all() */ } void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) @@ -319,9 +331,16 @@ int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, return -EINVAL; } +/** + * kvm_arch_vcpu_runnable - determine if the vcpu can be scheduled + * @v: The VCPU pointer + * + * If the guest CPU is not waiting for interrupts or an interrupt line is + * asserted, the CPU is by definition runnable. + */ int kvm_arch_vcpu_runnable(struct kvm_vcpu *v) { - return 0; + return !!v->arch.irq_lines; } /* Just ensure a guest exit from a particular CPU */ @@ -411,6 +430,110 @@ static void update_vttbr(struct kvm *kvm) spin_unlock(&kvm_vmid_lock); } +static int handle_svc_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + /* SVC called from Hyp mode should never get here */ + kvm_debug("SVC called from Hyp mode shouldn't go here\n"); + BUG(); + return -EINVAL; /* Squash warning */ +} + +static int handle_hvc(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + trace_kvm_hvc(*vcpu_pc(vcpu), *vcpu_reg(vcpu, 0), + vcpu->arch.hsr & HSR_HVC_IMM_MASK); + + kvm_inject_undefined(vcpu); + return 1; +} + +static int handle_smc(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + /* We don't support SMC; don't do that. */ + kvm_debug("smc: at %08x", *vcpu_pc(vcpu)); + kvm_inject_undefined(vcpu); + return 1; +} + +static int handle_pabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + /* The hypervisor should never cause aborts */ + kvm_err("Prefetch Abort taken from Hyp mode at %#08x (HSR: %#08x)\n", + vcpu->arch.hxfar, vcpu->arch.hsr); + return -EFAULT; +} + +static int handle_dabt_hyp(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + /* This is either an error in the ws. code or an external abort */ + kvm_err("Data Abort taken from Hyp mode at %#08x (HSR: %#08x)\n", + vcpu->arch.hxfar, vcpu->arch.hsr); + return -EFAULT; +} + +typedef int (*exit_handle_fn)(struct kvm_vcpu *, struct kvm_run *); +static exit_handle_fn arm_exit_handlers[] = { + [HSR_EC_WFI] = kvm_handle_wfi, + [HSR_EC_CP15_32] = kvm_handle_cp15_32, + [HSR_EC_CP15_64] = kvm_handle_cp15_64, + [HSR_EC_CP14_MR] = kvm_handle_cp14_access, + [HSR_EC_CP14_LS] = kvm_handle_cp14_load_store, + [HSR_EC_CP14_64] = kvm_handle_cp14_access, + [HSR_EC_CP_0_13] = kvm_handle_cp_0_13_access, + [HSR_EC_CP10_ID] = kvm_handle_cp10_id, + [HSR_EC_SVC_HYP] = handle_svc_hyp, + [HSR_EC_HVC] = handle_hvc, + [HSR_EC_SMC] = handle_smc, + [HSR_EC_IABT] = kvm_handle_guest_abort, + [HSR_EC_IABT_HYP] = handle_pabt_hyp, + [HSR_EC_DABT] = kvm_handle_guest_abort, + [HSR_EC_DABT_HYP] = handle_dabt_hyp, +}; + +/* + * A conditional instruction is allowed to trap, even though it + * wouldn't be executed. So let's re-implement the hardware, in + * software! + */ +static bool kvm_condition_valid(struct kvm_vcpu *vcpu) +{ + unsigned long cpsr, cond, insn; + + /* + * Exception Code 0 can only happen if we set HCR.TGE to 1, to + * catch undefined instructions, and then we won't get past + * the arm_exit_handlers test anyway. + */ + BUG_ON(((vcpu->arch.hsr & HSR_EC) >> HSR_EC_SHIFT) == 0); + + /* Top two bits non-zero? Unconditional. */ + if (vcpu->arch.hsr >> 30) + return true; + + cpsr = *vcpu_cpsr(vcpu); + + /* Is condition field valid? */ + if ((vcpu->arch.hsr & HSR_CV) >> HSR_CV_SHIFT) + cond = (vcpu->arch.hsr & HSR_COND) >> HSR_COND_SHIFT; + else { + /* This can happen in Thumb mode: examine IT state. */ + unsigned long it; + + it = ((cpsr >> 8) & 0xFC) | ((cpsr >> 25) & 0x3); + + /* it == 0 => unconditional. */ + if (it == 0) + return true; + + /* The cond for this insn works out as the top 4 bits. */ + cond = (it >> 4); + } + + /* Shift makes it look like an ARM-mode instruction */ + insn = cond << 28; + return arm_check_condition(insn, cpsr) != ARM_OPCODE_CONDTEST_FAIL; +} + /* * Return > 0 to return to guest, < 0 on error, 0 (and set exit_reason) on * proper exit to QEMU. @@ -418,8 +541,46 @@ static void update_vttbr(struct kvm *kvm) static int handle_exit(struct kvm_vcpu *vcpu, struct kvm_run *run, int exception_index) { - run->exit_reason = KVM_EXIT_INTERNAL_ERROR; - return 0; + unsigned long hsr_ec; + + switch (exception_index) { + case ARM_EXCEPTION_IRQ: + return 1; + case ARM_EXCEPTION_UNDEFINED: + kvm_err("Undefined exception in Hyp mode at: %#08x\n", + vcpu->arch.hyp_pc); + BUG(); + panic("KVM: Hypervisor undefined exception!\n"); + case ARM_EXCEPTION_DATA_ABORT: + case ARM_EXCEPTION_PREF_ABORT: + case ARM_EXCEPTION_HVC: + hsr_ec = (vcpu->arch.hsr & HSR_EC) >> HSR_EC_SHIFT; + + if (hsr_ec >= ARRAY_SIZE(arm_exit_handlers) + || !arm_exit_handlers[hsr_ec]) { + kvm_err("Unkown exception class: %#08lx, " + "hsr: %#08x\n", hsr_ec, + (unsigned int)vcpu->arch.hsr); + BUG(); + } + + /* + * See ARM ARM B1.14.1: "Hyp traps on instructions + * that fail their condition code check" + */ + if (!kvm_condition_valid(vcpu)) { + bool is_wide = vcpu->arch.hsr & HSR_IL; + kvm_skip_instr(vcpu, is_wide); + return 1; + } + + return arm_exit_handlers[hsr_ec](vcpu, run); + default: + kvm_pr_unimpl("Unsupported exception type: %d", + exception_index); + run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + return 0; + } } static int kvm_vcpu_first_run_init(struct kvm_vcpu *vcpu) @@ -493,6 +654,7 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) ret = kvm_call_hyp(__kvm_vcpu_run, vcpu); vcpu->mode = OUTSIDE_GUEST_MODE; + vcpu->arch.last_pcpu = smp_processor_id(); kvm_guest_exit(); trace_kvm_exit(*vcpu_pc(vcpu)); /* @@ -801,6 +963,7 @@ int kvm_arch_init(void *opaque) if (err) goto out_err; + kvm_coproc_table_init(); return 0; out_err: return err; diff --git a/arch/arm/kvm/coproc.c b/arch/arm/kvm/coproc.c index 0c43355..722efe3 100644 --- a/arch/arm/kvm/coproc.c +++ b/arch/arm/kvm/coproc.c @@ -16,8 +16,368 @@ * along with this program; if not, write to the Free Software * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ +#include <linux/mm.h> #include <linux/kvm_host.h> +#include <asm/kvm_arm.h> +#include <asm/kvm_host.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_coproc.h> +#include <asm/cacheflush.h> +#include <asm/cputype.h> +#include <trace/events/kvm.h> +#include "trace.h" +#include "coproc.h" + + +/****************************************************************************** + * Co-processor emulation + *****************************************************************************/ + +int kvm_handle_cp10_id(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + kvm_inject_undefined(vcpu); + return 1; +} + +int kvm_handle_cp_0_13_access(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + /* + * We can get here, if the host has been built without VFPv3 support, + * but the guest attempted a floating point operation. + */ + kvm_inject_undefined(vcpu); + return 1; +} + +int kvm_handle_cp14_load_store(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + kvm_inject_undefined(vcpu); + return 1; +} + +int kvm_handle_cp14_access(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + kvm_inject_undefined(vcpu); + return 1; +} + +/* See note at ARM ARM B1.14.4 */ +static bool access_dcsw(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + u32 val; + int cpu; + + cpu = get_cpu(); + + if (!p->is_write) + return read_from_write_only(vcpu, p); + + cpumask_setall(&vcpu->arch.require_dcache_flush); + cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush); + + /* If we were already preempted, take the long way around */ + if (cpu != vcpu->arch.last_pcpu) { + flush_cache_all(); + goto done; + } + + val = *vcpu_reg(vcpu, p->Rt1); + + switch (p->CRm) { + case 6: /* Upgrade DCISW to DCCISW, as per HCR.SWIO */ + case 14: /* DCCISW */ + asm volatile("mcr p15, 0, %0, c7, c14, 2" : : "r" (val)); + break; + + case 10: /* DCCSW */ + asm volatile("mcr p15, 0, %0, c7, c10, 2" : : "r" (val)); + break; + } + +done: + put_cpu(); + + return true; +} + +/* + * We could trap ID_DFR0 and tell the guest we don't support performance + * monitoring. Unfortunately the patch to make the kernel check ID_DFR0 was + * NAKed, so it will read the PMCR anyway. + * + * Therefore we tell the guest we have 0 counters. Unfortunately, we + * must always support PMCCNTR (the cycle counter): we just RAZ/WI for + * all PM registers, which doesn't crash the guest kernel at least. + */ +static bool pm_fake(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + if (p->is_write) + return ignore_write(vcpu, p); + else + return read_zero(vcpu, p); +} + +#define access_pmcr pm_fake +#define access_pmcntenset pm_fake +#define access_pmcntenclr pm_fake +#define access_pmovsr pm_fake +#define access_pmselr pm_fake +#define access_pmceid0 pm_fake +#define access_pmceid1 pm_fake +#define access_pmccntr pm_fake +#define access_pmxevtyper pm_fake +#define access_pmxevcntr pm_fake +#define access_pmuserenr pm_fake +#define access_pmintenset pm_fake +#define access_pmintenclr pm_fake + +/* Architected CP15 registers. + * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 + */ +static const struct coproc_reg cp15_regs[] = { + /* CSSELR: swapped by interrupt.S. */ + { CRn( 0), CRm( 0), Op1( 2), Op2( 0), is32, + NULL, reset_unknown, c0_CSSELR }, + + /* TTBR0/TTBR1: swapped by interrupt.S. */ + { CRm( 2), Op1( 0), is64, NULL, reset_unknown64, c2_TTBR0 }, + { CRm( 2), Op1( 1), is64, NULL, reset_unknown64, c2_TTBR1 }, + + /* TTBCR: swapped by interrupt.S. */ + { CRn( 2), CRm( 0), Op1( 0), Op2( 2), is32, + NULL, reset_val, c2_TTBCR, 0x00000000 }, + + /* DACR: swapped by interrupt.S. */ + { CRn( 3), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c3_DACR }, + + /* DFSR/IFSR/ADFSR/AIFSR: swapped by interrupt.S. */ + { CRn( 5), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c5_DFSR }, + { CRn( 5), CRm( 0), Op1( 0), Op2( 1), is32, + NULL, reset_unknown, c5_IFSR }, + { CRn( 5), CRm( 1), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c5_ADFSR }, + { CRn( 5), CRm( 1), Op1( 0), Op2( 1), is32, + NULL, reset_unknown, c5_AIFSR }, + + /* DFAR/IFAR: swapped by interrupt.S. */ + { CRn( 6), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c6_DFAR }, + { CRn( 6), CRm( 0), Op1( 0), Op2( 2), is32, + NULL, reset_unknown, c6_IFAR }, + /* + * DC{C,I,CI}SW operations: + */ + { CRn( 7), CRm( 6), Op1( 0), Op2( 2), is32, access_dcsw}, + { CRn( 7), CRm(10), Op1( 0), Op2( 2), is32, access_dcsw}, + { CRn( 7), CRm(14), Op1( 0), Op2( 2), is32, access_dcsw}, + /* + * Dummy performance monitor implementation. + */ + { CRn( 9), CRm(12), Op1( 0), Op2( 0), is32, access_pmcr}, + { CRn( 9), CRm(12), Op1( 0), Op2( 1), is32, access_pmcntenset}, + { CRn( 9), CRm(12), Op1( 0), Op2( 2), is32, access_pmcntenclr}, + { CRn( 9), CRm(12), Op1( 0), Op2( 3), is32, access_pmovsr}, + { CRn( 9), CRm(12), Op1( 0), Op2( 5), is32, access_pmselr}, + { CRn( 9), CRm(12), Op1( 0), Op2( 6), is32, access_pmceid0}, + { CRn( 9), CRm(12), Op1( 0), Op2( 7), is32, access_pmceid1}, + { CRn( 9), CRm(13), Op1( 0), Op2( 0), is32, access_pmccntr}, + { CRn( 9), CRm(13), Op1( 0), Op2( 1), is32, access_pmxevtyper}, + { CRn( 9), CRm(13), Op1( 0), Op2( 2), is32, access_pmxevcntr}, + { CRn( 9), CRm(14), Op1( 0), Op2( 0), is32, access_pmuserenr}, + { CRn( 9), CRm(14), Op1( 0), Op2( 1), is32, access_pmintenset}, + { CRn( 9), CRm(14), Op1( 0), Op2( 2), is32, access_pmintenclr}, + + /* PRRR/NMRR (aka MAIR0/MAIR1): swapped by interrupt.S. */ + { CRn(10), CRm( 2), Op1( 0), Op2( 0), is32, + NULL, reset_unknown, c10_PRRR}, + { CRn(10), CRm( 2), Op1( 0), Op2( 1), is32, + NULL, reset_unknown, c10_NMRR}, + + /* VBAR: swapped by interrupt.S. */ + { CRn(12), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_val, c12_VBAR, 0x00000000 }, + + /* CONTEXTIDR/TPIDRURW/TPIDRURO/TPIDRPRW: swapped by interrupt.S. */ + { CRn(13), CRm( 0), Op1( 0), Op2( 1), is32, + NULL, reset_val, c13_CID, 0x00000000 }, + { CRn(13), CRm( 0), Op1( 0), Op2( 2), is32, + NULL, reset_unknown, c13_TID_URW }, + { CRn(13), CRm( 0), Op1( 0), Op2( 3), is32, + NULL, reset_unknown, c13_TID_URO }, + { CRn(13), CRm( 0), Op1( 0), Op2( 4), is32, + NULL, reset_unknown, c13_TID_PRIV }, +}; + +/* Target specific emulation tables */ +static struct kvm_coproc_target_table *target_tables[KVM_ARM_NUM_TARGETS]; + +void kvm_register_target_coproc_table(struct kvm_coproc_target_table *table) +{ + target_tables[table->target] = table; +} + +/* Get specific register table for this target. */ +static const struct coproc_reg *get_target_table(unsigned target, size_t *num) +{ + struct kvm_coproc_target_table *table; + + table = target_tables[target]; + *num = table->num; + return table->table; +} + +static const struct coproc_reg *find_reg(const struct coproc_params *params, + const struct coproc_reg table[], + unsigned int num) +{ + unsigned int i; + + for (i = 0; i < num; i++) { + const struct coproc_reg *r = &table[i]; + + if (params->is_64bit != r->is_64) + continue; + if (params->CRn != r->CRn) + continue; + if (params->CRm != r->CRm) + continue; + if (params->Op1 != r->Op1) + continue; + if (params->Op2 != r->Op2) + continue; + + return r; + } + return NULL; +} + +static int emulate_cp15(struct kvm_vcpu *vcpu, + const struct coproc_params *params) +{ + size_t num; + const struct coproc_reg *table, *r; + + trace_kvm_emulate_cp15_imp(params->Op1, params->Rt1, params->CRn, + params->CRm, params->Op2, params->is_write); + + table = get_target_table(vcpu->arch.target, &num); + + /* Search target-specific then generic table. */ + r = find_reg(params, table, num); + if (!r) + r = find_reg(params, cp15_regs, ARRAY_SIZE(cp15_regs)); + + if (likely(r)) { + /* If we don't have an accessor, we should never get here! */ + BUG_ON(!r->access); + + if (likely(r->access(vcpu, params, r))) { + /* Skip instruction, since it was emulated */ + kvm_skip_instr(vcpu, (vcpu->arch.hsr >> 25) & 1); + return 1; + } + /* If access function fails, it should complain. */ + } else { + kvm_err("Unsupported guest CP15 access at: %08x\n", + *vcpu_pc(vcpu)); + print_cp_instr(params); + } + kvm_inject_undefined(vcpu); + return 1; +} + +/** + * kvm_handle_cp15_64 -- handles a mrrc/mcrr trap on a guest CP15 access + * @vcpu: The VCPU pointer + * @run: The kvm_run struct + */ +int kvm_handle_cp15_64(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + struct coproc_params params; + + params.CRm = (vcpu->arch.hsr >> 1) & 0xf; + params.Rt1 = (vcpu->arch.hsr >> 5) & 0xf; + params.is_write = ((vcpu->arch.hsr & 1) == 0); + params.is_64bit = true; + + params.Op1 = (vcpu->arch.hsr >> 16) & 0xf; + params.Op2 = 0; + params.Rt2 = (vcpu->arch.hsr >> 10) & 0xf; + params.CRn = 0; + + return emulate_cp15(vcpu, ¶ms); +} + +static void reset_coproc_regs(struct kvm_vcpu *vcpu, + const struct coproc_reg *table, size_t num) +{ + unsigned long i; + + for (i = 0; i < num; i++) + if (table[i].reset) + table[i].reset(vcpu, &table[i]); +} + +/** + * kvm_handle_cp15_32 -- handles a mrc/mcr trap on a guest CP15 access + * @vcpu: The VCPU pointer + * @run: The kvm_run struct + */ +int kvm_handle_cp15_32(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + struct coproc_params params; + + params.CRm = (vcpu->arch.hsr >> 1) & 0xf; + params.Rt1 = (vcpu->arch.hsr >> 5) & 0xf; + params.is_write = ((vcpu->arch.hsr & 1) == 0); + params.is_64bit = false; + + params.CRn = (vcpu->arch.hsr >> 10) & 0xf; + params.Op1 = (vcpu->arch.hsr >> 14) & 0x7; + params.Op2 = (vcpu->arch.hsr >> 17) & 0x7; + params.Rt2 = 0; + + return emulate_cp15(vcpu, ¶ms); +} + +void kvm_coproc_table_init(void) +{ + unsigned int i; + + /* Make sure tables are unique and in order. */ + for (i = 1; i < ARRAY_SIZE(cp15_regs); i++) + BUG_ON(cmp_reg(&cp15_regs[i-1], &cp15_regs[i]) >= 0); +} + +/** + * kvm_reset_coprocs - sets cp15 registers to reset value + * @vcpu: The VCPU pointer + * + * This function finds the right table above and sets the registers on the + * virtual CPU struct to their architecturally defined reset values. + */ void kvm_reset_coprocs(struct kvm_vcpu *vcpu) { + size_t num; + const struct coproc_reg *table; + + /* Catch someone adding a register without putting in reset entry. */ + memset(vcpu->arch.cp15, 0x42, sizeof(vcpu->arch.cp15)); + + /* Generic chip reset first (so target could override). */ + reset_coproc_regs(vcpu, cp15_regs, ARRAY_SIZE(cp15_regs)); + + table = get_target_table(vcpu->arch.target, &num); + reset_coproc_regs(vcpu, table, num); + + for (num = 1; num < NR_CP15_REGS; num++) + if (vcpu->arch.cp15[num] == 0x42424242) + panic("Didn't reset vcpu->arch.cp15[%zi]", num); } diff --git a/arch/arm/kvm/coproc.h b/arch/arm/kvm/coproc.h new file mode 100644 index 0000000..992adfa --- /dev/null +++ b/arch/arm/kvm/coproc.h @@ -0,0 +1,153 @@ +/* + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Authors: Christoffer Dall <c.dall@virtualopensystems.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, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ + +#ifndef __ARM_KVM_COPROC_LOCAL_H__ +#define __ARM_KVM_COPROC_LOCAL_H__ + +struct coproc_params { + unsigned long CRn; + unsigned long CRm; + unsigned long Op1; + unsigned long Op2; + unsigned long Rt1; + unsigned long Rt2; + bool is_64bit; + bool is_write; +}; + +struct coproc_reg { + /* MRC/MCR/MRRC/MCRR instruction which accesses it. */ + unsigned long CRn; + unsigned long CRm; + unsigned long Op1; + unsigned long Op2; + + bool is_64; + + /* Trapped access from guest, if non-NULL. */ + bool (*access)(struct kvm_vcpu *, + const struct coproc_params *, + const struct coproc_reg *); + + /* Initialization for vcpu. */ + void (*reset)(struct kvm_vcpu *, const struct coproc_reg *); + + /* Index into vcpu->arch.cp15[], or 0 if we don't need to save it. */ + unsigned long reg; + + /* Value (usually reset value) */ + u64 val; +}; + +static inline void print_cp_instr(const struct coproc_params *p) +{ + /* Look, we even formatted it for you to paste into the table! */ + if (p->is_64bit) { + kvm_pr_unimpl(" { CRm(%2lu), Op1(%2lu), is64, func_%s },\n", + p->CRm, p->Op1, p->is_write ? "write" : "read"); + } else { + kvm_pr_unimpl(" { CRn(%2lu), CRm(%2lu), Op1(%2lu), Op2(%2lu), is32," + " func_%s },\n", + p->CRn, p->CRm, p->Op1, p->Op2, + p->is_write ? "write" : "read"); + } +} + +static inline bool ignore_write(struct kvm_vcpu *vcpu, + const struct coproc_params *p) +{ + return true; +} + +static inline bool read_zero(struct kvm_vcpu *vcpu, + const struct coproc_params *p) +{ + *vcpu_reg(vcpu, p->Rt1) = 0; + return true; +} + +static inline bool write_to_read_only(struct kvm_vcpu *vcpu, + const struct coproc_params *params) +{ + kvm_debug("CP15 write to read-only register at: %08x\n", + *vcpu_pc(vcpu)); + print_cp_instr(params); + return false; +} + +static inline bool read_from_write_only(struct kvm_vcpu *vcpu, + const struct coproc_params *params) +{ + kvm_debug("CP15 read to write-only register at: %08x\n", + *vcpu_pc(vcpu)); + print_cp_instr(params); + return false; +} + +/* Reset functions */ +static inline void reset_unknown(struct kvm_vcpu *vcpu, + const struct coproc_reg *r) +{ + BUG_ON(!r->reg); + BUG_ON(r->reg >= ARRAY_SIZE(vcpu->arch.cp15)); + vcpu->arch.cp15[r->reg] = 0xdecafbad; +} + +static inline void reset_val(struct kvm_vcpu *vcpu, const struct coproc_reg *r) +{ + BUG_ON(!r->reg); + BUG_ON(r->reg >= ARRAY_SIZE(vcpu->arch.cp15)); + vcpu->arch.cp15[r->reg] = r->val; +} + +static inline void reset_unknown64(struct kvm_vcpu *vcpu, + const struct coproc_reg *r) +{ + BUG_ON(!r->reg); + BUG_ON(r->reg + 1 >= ARRAY_SIZE(vcpu->arch.cp15)); + + vcpu->arch.cp15[r->reg] = 0xdecafbad; + vcpu->arch.cp15[r->reg+1] = 0xd0c0ffee; +} + +static inline int cmp_reg(const struct coproc_reg *i1, + const struct coproc_reg *i2) +{ + BUG_ON(i1 == i2); + if (!i1) + return 1; + else if (!i2) + return -1; + if (i1->CRn != i2->CRn) + return i1->CRn - i2->CRn; + if (i1->CRm != i2->CRm) + return i1->CRm - i2->CRm; + if (i1->Op1 != i2->Op1) + return i1->Op1 - i2->Op1; + return i1->Op2 - i2->Op2; +} + + +#define CRn(_x) .CRn = _x +#define CRm(_x) .CRm = _x +#define Op1(_x) .Op1 = _x +#define Op2(_x) .Op2 = _x +#define is64 .is_64 = true +#define is32 .is_64 = false + +#endif /* __ARM_KVM_COPROC_LOCAL_H__ */ diff --git a/arch/arm/kvm/coproc_a15.c b/arch/arm/kvm/coproc_a15.c new file mode 100644 index 0000000..685063a --- /dev/null +++ b/arch/arm/kvm/coproc_a15.c @@ -0,0 +1,162 @@ +/* + * Copyright (C) 2012 - Virtual Open Systems and Columbia University + * Authors: Rusty Russell <rusty@rustcorp.au> + * Christoffer Dall <c.dall@virtualopensystems.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, write to the Free Software + * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. + */ +#include <linux/kvm_host.h> +#include <asm/cputype.h> +#include <asm/kvm_arm.h> +#include <asm/kvm_host.h> +#include <asm/kvm_emulate.h> +#include <asm/kvm_coproc.h> +#include <linux/init.h> + +static void reset_mpidr(struct kvm_vcpu *vcpu, const struct coproc_reg *r) +{ + /* + * Compute guest MPIDR: + * (Even if we present only one VCPU to the guest on an SMP + * host we don't set the U bit in the MPIDR, or vice versa, as + * revealing the underlying hardware properties is likely to + * be the best choice). + */ + vcpu->arch.cp15[c0_MPIDR] = (read_cpuid_mpidr() & ~MPIDR_LEVEL_MASK) + | (vcpu->vcpu_id & MPIDR_LEVEL_MASK); +} + +#include "coproc.h" + +/* A15 TRM 4.3.28: RO WI */ +static bool access_actlr(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + if (p->is_write) + return ignore_write(vcpu, p); + + *vcpu_reg(vcpu, p->Rt1) = vcpu->arch.cp15[c1_ACTLR]; + return true; +} + +/* A15 TRM 4.3.60: R/O. */ +static bool access_cbar(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + if (p->is_write) + return write_to_read_only(vcpu, p); + return read_zero(vcpu, p); +} + +/* A15 TRM 4.3.48: R/O WI. */ +static bool access_l2ctlr(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + if (p->is_write) + return ignore_write(vcpu, p); + + *vcpu_reg(vcpu, p->Rt1) = vcpu->arch.cp15[c9_L2CTLR]; + return true; +} + +static void reset_l2ctlr(struct kvm_vcpu *vcpu, const struct coproc_reg *r) +{ + u32 l2ctlr, ncores; + + asm volatile("mrc p15, 1, %0, c9, c0, 2\n" : "=r" (l2ctlr)); + l2ctlr &= ~(3 << 24); + ncores = atomic_read(&vcpu->kvm->online_vcpus) - 1; + l2ctlr |= (ncores & 3) << 24; + + vcpu->arch.cp15[c9_L2CTLR] = l2ctlr; +} + +static void reset_actlr(struct kvm_vcpu *vcpu, const struct coproc_reg *r) +{ + u32 actlr; + + /* ACTLR contains SMP bit: make sure you create all cpus first! */ + asm volatile("mrc p15, 0, %0, c1, c0, 1\n" : "=r" (actlr)); + /* Make the SMP bit consistent with the guest configuration */ + if (atomic_read(&vcpu->kvm->online_vcpus) > 1) + actlr |= 1U << 6; + else + actlr &= ~(1U << 6); + + vcpu->arch.cp15[c1_ACTLR] = actlr; +} + +/* A15 TRM 4.3.49: R/O WI (even if NSACR.NS_L2ERR, a write of 1 is ignored). */ +static bool access_l2ectlr(struct kvm_vcpu *vcpu, + const struct coproc_params *p, + const struct coproc_reg *r) +{ + if (p->is_write) + return ignore_write(vcpu, p); + + *vcpu_reg(vcpu, p->Rt1) = 0; + return true; +} + +/* + * A15-specific CP15 registers. + * Important: Must be sorted ascending by CRn, CRM, Op1, Op2 + */ +static const struct coproc_reg a15_regs[] = { + /* MPIDR: we use VMPIDR for guest access. */ + { CRn( 0), CRm( 0), Op1( 0), Op2( 5), is32, + NULL, reset_mpidr, c0_MPIDR }, + + /* SCTLR: swapped by interrupt.S. */ + { CRn( 1), CRm( 0), Op1( 0), Op2( 0), is32, + NULL, reset_val, c1_SCTLR, 0x00C50078 }, + /* ACTLR: trapped by HCR.TAC bit. */ + { CRn( 1), CRm( 0), Op1( 0), Op2( 1), is32, + access_actlr, reset_actlr, c1_ACTLR }, + /* CPACR: swapped by interrupt.S. */ + { CRn( 1), CRm( 0), Op1( 0), Op2( 2), is32, + NULL, reset_val, c1_CPACR, 0x00000000 }, + + /* + * L2CTLR access (guest wants to know #CPUs). + */ + { CRn( 9), CRm( 0), Op1( 1), Op2( 2), is32, + access_l2ctlr, reset_l2ctlr, c9_L2CTLR }, + { CRn( 9), CRm( 0), Op1( 1), Op2( 3), is32, access_l2ectlr}, + + /* The Configuration Base Address Register. */ + { CRn(15), CRm( 0), Op1( 4), Op2( 0), is32, access_cbar}, +}; + +static struct kvm_coproc_target_table a15_target_table = { + .target = KVM_ARM_TARGET_CORTEX_A15, + .table = a15_regs, + .num = ARRAY_SIZE(a15_regs), +}; + +static int __init coproc_a15_init(void) +{ + unsigned int i; + + for (i = 1; i < ARRAY_SIZE(a15_regs); i++) + BUG_ON(cmp_reg(&a15_regs[i-1], + &a15_regs[i]) >= 0); + + kvm_register_target_coproc_table(&a15_target_table); + return 0; +} +late_initcall(coproc_a15_init); diff --git a/arch/arm/kvm/emulate.c b/arch/arm/kvm/emulate.c index 3eadc25..d61450a 100644 --- a/arch/arm/kvm/emulate.c +++ b/arch/arm/kvm/emulate.c @@ -16,7 +16,13 @@ * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ +#include <linux/mm.h> +#include <linux/kvm_host.h> +#include <asm/kvm_arm.h> #include <asm/kvm_emulate.h> +#include <trace/events/kvm.h> + +#include "trace.h" #define VCPU_NR_MODES 6 #define VCPU_REG_OFFSET_USR 0 @@ -153,3 +159,215 @@ u32 *vcpu_spsr(struct kvm_vcpu *vcpu) BUG(); } } + +/** + * kvm_handle_wfi - handle a wait-for-interrupts instruction executed by a guest + * @vcpu: the vcpu pointer + * @run: the kvm_run structure pointer + * + * Simply sets the wait_for_interrupts flag on the vcpu structure, which will + * halt execution of world-switches and schedule other host processes until + * there is an incoming IRQ or FIQ to the VM. + */ +int kvm_handle_wfi(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + trace_kvm_wfi(*vcpu_pc(vcpu)); + kvm_vcpu_block(vcpu); + return 1; +} + +/** + * adjust_itstate - adjust ITSTATE when emulating instructions in IT-block + * @vcpu: The VCPU pointer + * + * When exceptions occur while instructions are executed in Thumb IF-THEN + * blocks, the ITSTATE field of the CPSR is not advanved (updated), so we have + * to do this little bit of work manually. The fields map like this: + * + * IT[7:0] -> CPSR[26:25],CPSR[15:10] + */ +static void kvm_adjust_itstate(struct kvm_vcpu *vcpu) +{ + unsigned long itbits, cond; + unsigned long cpsr = *vcpu_cpsr(vcpu); + bool is_arm = !(cpsr & PSR_T_BIT); + + BUG_ON(is_arm && (cpsr & PSR_IT_MASK)); + + if (!(cpsr & PSR_IT_MASK)) + return; + + cond = (cpsr & 0xe000) >> 13; + itbits = (cpsr & 0x1c00) >> (10 - 2); + itbits |= (cpsr & (0x3 << 25)) >> 25; + + /* Perform ITAdvance (see page A-52 in ARM DDI 0406C) */ + if ((itbits & 0x7) == 0) + itbits = cond = 0; + else + itbits = (itbits << 1) & 0x1f; + + cpsr &= ~PSR_IT_MASK; + cpsr |= cond << 13; + cpsr |= (itbits & 0x1c) << (10 - 2); + cpsr |= (itbits & 0x3) << 25; + *vcpu_cpsr(vcpu) = cpsr; +} + +/** + * kvm_skip_instr - skip a trapped instruction and proceed to the next + * @vcpu: The vcpu pointer + */ +void kvm_skip_instr(struct kvm_vcpu *vcpu, bool is_wide_instr) +{ + bool is_thumb; + + is_thumb = !!(*vcpu_cpsr(vcpu) & PSR_T_BIT); + if (is_thumb && !is_wide_instr) + *vcpu_pc(vcpu) += 2; + else + *vcpu_pc(vcpu) += 4; + kvm_adjust_itstate(vcpu); +} + + +/****************************************************************************** + * Inject exceptions into the guest + */ + +static u32 exc_vector_base(struct kvm_vcpu *vcpu) +{ + u32 sctlr = vcpu->arch.cp15[c1_SCTLR]; + u32 vbar = vcpu->arch.cp15[c12_VBAR]; + + if (sctlr & SCTLR_V) + return 0xffff0000; + else /* always have security exceptions */ + return vbar; +} + +/** + * kvm_inject_undefined - inject an undefined exception into the guest + * @vcpu: The VCPU to receive the undefined exception + * + * It is assumed that this code is called from the VCPU thread and that the + * VCPU therefore is not currently executing guest code. + * + * Modelled after TakeUndefInstrException() pseudocode. + */ +void kvm_inject_undefined(struct kvm_vcpu *vcpu) +{ + u32 new_lr_value; + u32 new_spsr_value; + u32 cpsr = *vcpu_cpsr(vcpu); + u32 sctlr = vcpu->arch.cp15[c1_SCTLR]; + bool is_thumb = (cpsr & PSR_T_BIT); + u32 vect_offset = 4; + u32 return_offset = (is_thumb) ? 2 : 4; + + new_spsr_value = cpsr; + new_lr_value = *vcpu_pc(vcpu) - return_offset; + + *vcpu_cpsr(vcpu) = (cpsr & ~MODE_MASK) | UND_MODE; + *vcpu_cpsr(vcpu) |= PSR_I_BIT; + *vcpu_cpsr(vcpu) &= ~(PSR_IT_MASK | PSR_J_BIT | PSR_E_BIT | PSR_T_BIT); + + if (sctlr & SCTLR_TE) + *vcpu_cpsr(vcpu) |= PSR_T_BIT; + if (sctlr & SCTLR_EE) + *vcpu_cpsr(vcpu) |= PSR_E_BIT; + + /* Note: These now point to UND banked copies */ + *vcpu_spsr(vcpu) = cpsr; + *vcpu_reg(vcpu, 14) = new_lr_value; + + /* Branch to exception vector */ + *vcpu_pc(vcpu) = exc_vector_base(vcpu) + vect_offset; +} + +/* + * Modelled after TakeDataAbortException() and TakePrefetchAbortException + * pseudocode. + */ +static void inject_abt(struct kvm_vcpu *vcpu, bool is_pabt, unsigned long addr) +{ + u32 new_lr_value; + u32 new_spsr_value; + u32 cpsr = *vcpu_cpsr(vcpu); + u32 sctlr = vcpu->arch.cp15[c1_SCTLR]; + bool is_thumb = (cpsr & PSR_T_BIT); + u32 vect_offset; + u32 return_offset = (is_thumb) ? 4 : 0; + bool is_lpae; + + new_spsr_value = cpsr; + new_lr_value = *vcpu_pc(vcpu) + return_offset; + + *vcpu_cpsr(vcpu) = (cpsr & ~MODE_MASK) | ABT_MODE; + *vcpu_cpsr(vcpu) |= PSR_I_BIT | PSR_A_BIT; + *vcpu_cpsr(vcpu) &= ~(PSR_IT_MASK | PSR_J_BIT | PSR_E_BIT | PSR_T_BIT); + + if (sctlr & SCTLR_TE) + *vcpu_cpsr(vcpu) |= PSR_T_BIT; + if (sctlr & SCTLR_EE) + *vcpu_cpsr(vcpu) |= PSR_E_BIT; + + /* Note: These now point to ABT banked copies */ + *vcpu_spsr(vcpu) = cpsr; + *vcpu_reg(vcpu, 14) = new_lr_value; + + if (is_pabt) + vect_offset = 12; + else + vect_offset = 16; + + /* Branch to exception vector */ + *vcpu_pc(vcpu) = exc_vector_base(vcpu) + vect_offset; + + if (is_pabt) { + /* Set DFAR and DFSR */ + vcpu->arch.cp15[c6_IFAR] = addr; + is_lpae = (vcpu->arch.cp15[c2_TTBCR] >> 31); + /* Always give debug fault for now - should give guest a clue */ + if (is_lpae) + vcpu->arch.cp15[c5_IFSR] = 1 << 9 | 0x22; + else + vcpu->arch.cp15[c5_IFSR] = 2; + } else { /* !iabt */ + /* Set DFAR and DFSR */ + vcpu->arch.cp15[c6_DFAR] = addr; + is_lpae = (vcpu->arch.cp15[c2_TTBCR] >> 31); + /* Always give debug fault for now - should give guest a clue */ + if (is_lpae) + vcpu->arch.cp15[c5_DFSR] = 1 << 9 | 0x22; + else + vcpu->arch.cp15[c5_DFSR] = 2; + } + +} + +/** + * kvm_inject_dabt - inject a data abort into the guest + * @vcpu: The VCPU to receive the undefined exception + * @addr: The address to report in the DFAR + * + * It is assumed that this code is called from the VCPU thread and that the + * VCPU therefore is not currently executing guest code. + */ +void kvm_inject_dabt(struct kvm_vcpu *vcpu, unsigned long addr) +{ + inject_abt(vcpu, false, addr); +} + +/** + * kvm_inject_pabt - inject a prefetch abort into the guest + * @vcpu: The VCPU to receive the undefined exception + * @addr: The address to report in the DFAR + * + * It is assumed that this code is called from the VCPU thread and that the + * VCPU therefore is not currently executing guest code. + */ +void kvm_inject_pabt(struct kvm_vcpu *vcpu, unsigned long addr) +{ + inject_abt(vcpu, true, addr); +} diff --git a/arch/arm/kvm/trace.h b/arch/arm/kvm/trace.h index 105d1f7..022305b 100644 --- a/arch/arm/kvm/trace.h +++ b/arch/arm/kvm/trace.h @@ -64,6 +64,51 @@ TRACE_EVENT(kvm_irq_line, __entry->type, __entry->vcpu_idx, __entry->irq_num, __entry->level) ); +/* Architecturally implementation defined CP15 register access */ +TRACE_EVENT(kvm_emulate_cp15_imp, + TP_PROTO(unsigned long Op1, unsigned long Rt1, unsigned long CRn, + unsigned long CRm, unsigned long Op2, bool is_write), + TP_ARGS(Op1, Rt1, CRn, CRm, Op2, is_write), + + TP_STRUCT__entry( + __field( unsigned int, Op1 ) + __field( unsigned int, Rt1 ) + __field( unsigned int, CRn ) + __field( unsigned int, CRm ) + __field( unsigned int, Op2 ) + __field( bool, is_write ) + ), + + TP_fast_assign( + __entry->is_write = is_write; + __entry->Op1 = Op1; + __entry->Rt1 = Rt1; + __entry->CRn = CRn; + __entry->CRm = CRm; + __entry->Op2 = Op2; + ), + + TP_printk("Implementation defined CP15: %s\tp15, %u, r%u, c%u, c%u, %u", + (__entry->is_write) ? "mcr" : "mrc", + __entry->Op1, __entry->Rt1, __entry->CRn, + __entry->CRm, __entry->Op2) +); + +TRACE_EVENT(kvm_wfi, + TP_PROTO(unsigned long vcpu_pc), + TP_ARGS(vcpu_pc), + + TP_STRUCT__entry( + __field( unsigned long, vcpu_pc ) + ), + + TP_fast_assign( + __entry->vcpu_pc = vcpu_pc; + ), + + TP_printk("guest executed wfi at: 0x%08lx", __entry->vcpu_pc) +); + TRACE_EVENT(kvm_unmap_hva, TP_PROTO(unsigned long hva), TP_ARGS(hva), @@ -112,6 +157,26 @@ TRACE_EVENT(kvm_set_spte_hva, TP_printk("mmu notifier set pte hva: %#08lx", __entry->hva) ); +TRACE_EVENT(kvm_hvc, + TP_PROTO(unsigned long vcpu_pc, unsigned long r0, unsigned long imm), + TP_ARGS(vcpu_pc, r0, imm), + + TP_STRUCT__entry( + __field( unsigned long, vcpu_pc ) + __field( unsigned long, r0 ) + __field( unsigned long, imm ) + ), + + TP_fast_assign( + __entry->vcpu_pc = vcpu_pc; + __entry->r0 = r0; + __entry->imm = imm; + ), + + TP_printk("HVC at 0x%08lx (r0: 0x%08lx, imm: 0x%lx", + __entry->vcpu_pc, __entry->r0, __entry->imm) +); + #endif /* _TRACE_KVM_H */ #undef TRACE_INCLUDE_PATH |