diff options
Diffstat (limited to 'target-arm/kvm.c')
| -rw-r--r-- | target-arm/kvm.c | 267 |
1 files changed, 196 insertions, 71 deletions
diff --git a/target-arm/kvm.c b/target-arm/kvm.c index 4aea7c3390..b9c9127d9c 100644 --- a/target-arm/kvm.c +++ b/target-arm/kvm.c @@ -50,12 +50,35 @@ unsigned long kvm_arch_vcpu_id(CPUState *cpu) return cpu->cpu_index; } +static bool reg_syncs_via_tuple_list(uint64_t regidx) +{ + /* Return true if the regidx is a register we should synchronize + * via the cpreg_tuples array (ie is not a core reg we sync by + * hand in kvm_arch_get/put_registers()) + */ + switch (regidx & KVM_REG_ARM_COPROC_MASK) { + case KVM_REG_ARM_CORE: + case KVM_REG_ARM_VFP: + return false; + default: + return true; + } +} + +static int compare_u64(const void *a, const void *b) +{ + return *(uint64_t *)a - *(uint64_t *)b; +} + int kvm_arch_init_vcpu(CPUState *cs) { struct kvm_vcpu_init init; - int ret; + int i, ret, arraylen; uint64_t v; struct kvm_one_reg r; + struct kvm_reg_list rl; + struct kvm_reg_list *rlp; + ARMCPU *cpu = ARM_CPU(cs); init.target = KVM_ARM_TARGET_CORTEX_A15; memset(init.features, 0, sizeof(init.features)); @@ -74,6 +97,73 @@ int kvm_arch_init_vcpu(CPUState *cs) if (ret == -ENOENT) { return -EINVAL; } + + /* Populate the cpreg list based on the kernel's idea + * of what registers exist (and throw away the TCG-created list). + */ + rl.n = 0; + ret = kvm_vcpu_ioctl(cs, KVM_GET_REG_LIST, &rl); + if (ret != -E2BIG) { + return ret; + } + rlp = g_malloc(sizeof(struct kvm_reg_list) + rl.n * sizeof(uint64_t)); + rlp->n = rl.n; + ret = kvm_vcpu_ioctl(cs, KVM_GET_REG_LIST, rlp); + if (ret) { + goto out; + } + /* Sort the list we get back from the kernel, since cpreg_tuples + * must be in strictly ascending order. + */ + qsort(&rlp->reg, rlp->n, sizeof(rlp->reg[0]), compare_u64); + + for (i = 0, arraylen = 0; i < rlp->n; i++) { + if (!reg_syncs_via_tuple_list(rlp->reg[i])) { + continue; + } + switch (rlp->reg[i] & KVM_REG_SIZE_MASK) { + case KVM_REG_SIZE_U32: + case KVM_REG_SIZE_U64: + break; + default: + fprintf(stderr, "Can't handle size of register in kernel list\n"); + ret = -EINVAL; + goto out; + } + + arraylen++; + } + + cpu->cpreg_indexes = g_renew(uint64_t, cpu->cpreg_indexes, arraylen); + cpu->cpreg_values = g_renew(uint64_t, cpu->cpreg_values, arraylen); + cpu->cpreg_vmstate_indexes = g_renew(uint64_t, cpu->cpreg_vmstate_indexes, + arraylen); + cpu->cpreg_vmstate_values = g_renew(uint64_t, cpu->cpreg_vmstate_values, + arraylen); + cpu->cpreg_array_len = arraylen; + cpu->cpreg_vmstate_array_len = arraylen; + + for (i = 0, arraylen = 0; i < rlp->n; i++) { + uint64_t regidx = rlp->reg[i]; + if (!reg_syncs_via_tuple_list(regidx)) { + continue; + } + cpu->cpreg_indexes[arraylen] = regidx; + arraylen++; + } + assert(cpu->cpreg_array_len == arraylen); + + if (!write_kvmstate_to_list(cpu)) { + /* Shouldn't happen unless kernel is inconsistent about + * what registers exist. + */ + fprintf(stderr, "Initial read of kernel register state failed\n"); + ret = -EINVAL; + goto out; + } + +out: + g_free(rlp); return ret; } @@ -163,6 +253,78 @@ void kvm_arm_register_device(MemoryRegion *mr, uint64_t devid) QSLIST_INSERT_HEAD(&kvm_devices_head, kd, entries); } +bool write_kvmstate_to_list(ARMCPU *cpu) +{ + CPUState *cs = CPU(cpu); + int i; + bool ok = true; + + for (i = 0; i < cpu->cpreg_array_len; i++) { + struct kvm_one_reg r; + uint64_t regidx = cpu->cpreg_indexes[i]; + uint32_t v32; + int ret; + + r.id = regidx; + + switch (regidx & KVM_REG_SIZE_MASK) { + case KVM_REG_SIZE_U32: + r.addr = (uintptr_t)&v32; + ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r); + if (!ret) { + cpu->cpreg_values[i] = v32; + } + break; + case KVM_REG_SIZE_U64: + r.addr = (uintptr_t)(cpu->cpreg_values + i); + ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r); + break; + default: + abort(); + } + if (ret) { + ok = false; + } + } + return ok; +} + +bool write_list_to_kvmstate(ARMCPU *cpu) +{ + CPUState *cs = CPU(cpu); + int i; + bool ok = true; + + for (i = 0; i < cpu->cpreg_array_len; i++) { + struct kvm_one_reg r; + uint64_t regidx = cpu->cpreg_indexes[i]; + uint32_t v32; + int ret; + + r.id = regidx; + switch (regidx & KVM_REG_SIZE_MASK) { + case KVM_REG_SIZE_U32: + v32 = cpu->cpreg_values[i]; + r.addr = (uintptr_t)&v32; + break; + case KVM_REG_SIZE_U64: + r.addr = (uintptr_t)(cpu->cpreg_values + i); + break; + default: + abort(); + } + ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r); + if (ret) { + /* We might fail for "unknown register" and also for + * "you tried to set a register which is constant with + * a different value from what it actually contains". + */ + ok = false; + } + } + return ok; +} + typedef struct Reg { uint64_t id; int offset; @@ -175,17 +337,6 @@ typedef struct Reg { offsetof(CPUARMState, QEMUFIELD) \ } -#define CP15REG(CRN, CRM, OPC1, OPC2, QEMUFIELD) \ - { \ - KVM_REG_ARM | KVM_REG_SIZE_U32 | \ - (15 << KVM_REG_ARM_COPROC_SHIFT) | \ - ((CRN) << KVM_REG_ARM_32_CRN_SHIFT) | \ - ((CRM) << KVM_REG_ARM_CRM_SHIFT) | \ - ((OPC1) << KVM_REG_ARM_OPC1_SHIFT) | \ - ((OPC2) << KVM_REG_ARM_32_OPC2_SHIFT), \ - offsetof(CPUARMState, QEMUFIELD) \ - } - #define VFPSYSREG(R) \ { \ KVM_REG_ARM | KVM_REG_SIZE_U32 | KVM_REG_ARM_VFP | \ @@ -234,12 +385,6 @@ static const Reg regs[] = { COREREG(fiq_regs[7], banked_spsr[5]), /* R15 */ COREREG(usr_regs.uregs[15], regs[15]), - /* A non-comprehensive set of cp15 registers. - * TODO: drive this from the cp_regs hashtable instead. - */ - CP15REG(1, 0, 0, 0, cp15.c1_sys), /* SCTLR */ - CP15REG(2, 0, 0, 2, cp15.c2_control), /* TTBCR */ - CP15REG(3, 0, 0, 0, cp15.c3), /* DACR */ /* VFP system registers */ VFPSYSREG(FPSID), VFPSYSREG(MVFR1), @@ -257,7 +402,6 @@ int kvm_arch_put_registers(CPUState *cs, int level) int mode, bn; int ret, i; uint32_t cpsr, fpscr; - uint64_t ttbr; /* Make sure the banked regs are properly set */ mode = env->uncached_cpsr & CPSR_M; @@ -291,26 +435,6 @@ int kvm_arch_put_registers(CPUState *cs, int level) return ret; } - /* TTBR0: cp15 crm=2 opc1=0 */ - ttbr = ((uint64_t)env->cp15.c2_base0_hi << 32) | env->cp15.c2_base0; - r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | (15 << KVM_REG_ARM_COPROC_SHIFT) | - (2 << KVM_REG_ARM_CRM_SHIFT) | (0 << KVM_REG_ARM_OPC1_SHIFT); - r.addr = (uintptr_t)(&ttbr); - ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r); - if (ret) { - return ret; - } - - /* TTBR1: cp15 crm=2 opc1=1 */ - ttbr = ((uint64_t)env->cp15.c2_base1_hi << 32) | env->cp15.c2_base1; - r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | (15 << KVM_REG_ARM_COPROC_SHIFT) | - (2 << KVM_REG_ARM_CRM_SHIFT) | (1 << KVM_REG_ARM_OPC1_SHIFT); - r.addr = (uintptr_t)(&ttbr); - ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r); - if (ret) { - return ret; - } - /* VFP registers */ r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP; for (i = 0; i < 32; i++) { @@ -327,6 +451,31 @@ int kvm_arch_put_registers(CPUState *cs, int level) fpscr = vfp_get_fpscr(env); r.addr = (uintptr_t)&fpscr; ret = kvm_vcpu_ioctl(cs, KVM_SET_ONE_REG, &r); + if (ret) { + return ret; + } + + /* Note that we do not call write_cpustate_to_list() + * here, so we are only writing the tuple list back to + * KVM. This is safe because nothing can change the + * CPUARMState cp15 fields (in particular gdb accesses cannot) + * and so there are no changes to sync. In fact syncing would + * be wrong at this point: for a constant register where TCG and + * KVM disagree about its value, the preceding write_list_to_cpustate() + * would not have had any effect on the CPUARMState value (since the + * register is read-only), and a write_cpustate_to_list() here would + * then try to write the TCG value back into KVM -- this would either + * fail or incorrectly change the value the guest sees. + * + * If we ever want to allow the user to modify cp15 registers via + * the gdb stub, we would need to be more clever here (for instance + * tracking the set of registers kvm_arch_get_registers() successfully + * managed to update the CPUARMState with, and only allowing those + * to be written back up into the kernel). + */ + if (!write_list_to_kvmstate(cpu)) { + return EINVAL; + } return ret; } @@ -339,7 +488,6 @@ int kvm_arch_get_registers(CPUState *cs) int mode, bn; int ret, i; uint32_t cpsr, fpscr; - uint64_t ttbr; for (i = 0; i < ARRAY_SIZE(regs); i++) { r.id = regs[i].id; @@ -360,28 +508,6 @@ int kvm_arch_get_registers(CPUState *cs) } cpsr_write(env, cpsr, 0xffffffff); - /* TTBR0: cp15 crm=2 opc1=0 */ - r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | (15 << KVM_REG_ARM_COPROC_SHIFT) | - (2 << KVM_REG_ARM_CRM_SHIFT) | (0 << KVM_REG_ARM_OPC1_SHIFT); - r.addr = (uintptr_t)(&ttbr); - ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r); - if (ret) { - return ret; - } - env->cp15.c2_base0_hi = ttbr >> 32; - env->cp15.c2_base0 = ttbr; - - /* TTBR1: cp15 crm=2 opc1=1 */ - r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | (15 << KVM_REG_ARM_COPROC_SHIFT) | - (2 << KVM_REG_ARM_CRM_SHIFT) | (1 << KVM_REG_ARM_OPC1_SHIFT); - r.addr = (uintptr_t)(&ttbr); - ret = kvm_vcpu_ioctl(cs, KVM_GET_ONE_REG, &r); - if (ret) { - return ret; - } - env->cp15.c2_base1_hi = ttbr >> 32; - env->cp15.c2_base1 = ttbr; - /* Make sure the current mode regs are properly set */ mode = env->uncached_cpsr & CPSR_M; bn = bank_number(mode); @@ -394,15 +520,6 @@ int kvm_arch_get_registers(CPUState *cs) env->regs[14] = env->banked_r14[bn]; env->spsr = env->banked_spsr[bn]; - /* The main GET_ONE_REG loop above set c2_control, but we need to - * update some extra cached precomputed values too. - * When this is driven from the cp_regs hashtable then this ugliness - * can disappear because we'll use the access function which sets - * these values automatically. - */ - env->cp15.c2_mask = ~(0xffffffffu >> env->cp15.c2_control); - env->cp15.c2_base_mask = ~(0x3fffu >> env->cp15.c2_control); - /* VFP registers */ r.id = KVM_REG_ARM | KVM_REG_SIZE_U64 | KVM_REG_ARM_VFP; for (i = 0; i < 32; i++) { @@ -423,6 +540,14 @@ int kvm_arch_get_registers(CPUState *cs) } vfp_set_fpscr(env, fpscr); + if (!write_kvmstate_to_list(cpu)) { + return EINVAL; + } + /* Note that it's OK to have registers which aren't in CPUState, + * so we can ignore a failure return here. + */ + write_list_to_cpustate(cpu); + return 0; } |