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Diffstat (limited to '')
-rw-r--r-- | arch/mips/kvm/mips.c | 1732 |
1 files changed, 1732 insertions, 0 deletions
diff --git a/arch/mips/kvm/mips.c b/arch/mips/kvm/mips.c new file mode 100644 index 000000000..79485790f --- /dev/null +++ b/arch/mips/kvm/mips.c @@ -0,0 +1,1732 @@ +/* + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file "COPYING" in the main directory of this archive + * for more details. + * + * KVM/MIPS: MIPS specific KVM APIs + * + * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved. + * Authors: Sanjay Lal <sanjayl@kymasys.com> + */ + +#include <linux/bitops.h> +#include <linux/errno.h> +#include <linux/err.h> +#include <linux/kdebug.h> +#include <linux/module.h> +#include <linux/uaccess.h> +#include <linux/vmalloc.h> +#include <linux/sched/signal.h> +#include <linux/fs.h> +#include <linux/bootmem.h> + +#include <asm/fpu.h> +#include <asm/page.h> +#include <asm/cacheflush.h> +#include <asm/mmu_context.h> +#include <asm/pgalloc.h> +#include <asm/pgtable.h> + +#include <linux/kvm_host.h> + +#include "interrupt.h" +#include "commpage.h" + +#define CREATE_TRACE_POINTS +#include "trace.h" + +#ifndef VECTORSPACING +#define VECTORSPACING 0x100 /* for EI/VI mode */ +#endif + +#define VCPU_STAT(x) offsetof(struct kvm_vcpu, stat.x) +struct kvm_stats_debugfs_item debugfs_entries[] = { + { "wait", VCPU_STAT(wait_exits), KVM_STAT_VCPU }, + { "cache", VCPU_STAT(cache_exits), KVM_STAT_VCPU }, + { "signal", VCPU_STAT(signal_exits), KVM_STAT_VCPU }, + { "interrupt", VCPU_STAT(int_exits), KVM_STAT_VCPU }, + { "cop_unusable", VCPU_STAT(cop_unusable_exits), KVM_STAT_VCPU }, + { "tlbmod", VCPU_STAT(tlbmod_exits), KVM_STAT_VCPU }, + { "tlbmiss_ld", VCPU_STAT(tlbmiss_ld_exits), KVM_STAT_VCPU }, + { "tlbmiss_st", VCPU_STAT(tlbmiss_st_exits), KVM_STAT_VCPU }, + { "addrerr_st", VCPU_STAT(addrerr_st_exits), KVM_STAT_VCPU }, + { "addrerr_ld", VCPU_STAT(addrerr_ld_exits), KVM_STAT_VCPU }, + { "syscall", VCPU_STAT(syscall_exits), KVM_STAT_VCPU }, + { "resvd_inst", VCPU_STAT(resvd_inst_exits), KVM_STAT_VCPU }, + { "break_inst", VCPU_STAT(break_inst_exits), KVM_STAT_VCPU }, + { "trap_inst", VCPU_STAT(trap_inst_exits), KVM_STAT_VCPU }, + { "msa_fpe", VCPU_STAT(msa_fpe_exits), KVM_STAT_VCPU }, + { "fpe", VCPU_STAT(fpe_exits), KVM_STAT_VCPU }, + { "msa_disabled", VCPU_STAT(msa_disabled_exits), KVM_STAT_VCPU }, + { "flush_dcache", VCPU_STAT(flush_dcache_exits), KVM_STAT_VCPU }, +#ifdef CONFIG_KVM_MIPS_VZ + { "vz_gpsi", VCPU_STAT(vz_gpsi_exits), KVM_STAT_VCPU }, + { "vz_gsfc", VCPU_STAT(vz_gsfc_exits), KVM_STAT_VCPU }, + { "vz_hc", VCPU_STAT(vz_hc_exits), KVM_STAT_VCPU }, + { "vz_grr", VCPU_STAT(vz_grr_exits), KVM_STAT_VCPU }, + { "vz_gva", VCPU_STAT(vz_gva_exits), KVM_STAT_VCPU }, + { "vz_ghfc", VCPU_STAT(vz_ghfc_exits), KVM_STAT_VCPU }, + { "vz_gpa", VCPU_STAT(vz_gpa_exits), KVM_STAT_VCPU }, + { "vz_resvd", VCPU_STAT(vz_resvd_exits), KVM_STAT_VCPU }, +#endif + { "halt_successful_poll", VCPU_STAT(halt_successful_poll), KVM_STAT_VCPU }, + { "halt_attempted_poll", VCPU_STAT(halt_attempted_poll), KVM_STAT_VCPU }, + { "halt_poll_invalid", VCPU_STAT(halt_poll_invalid), KVM_STAT_VCPU }, + { "halt_wakeup", VCPU_STAT(halt_wakeup), KVM_STAT_VCPU }, + {NULL} +}; + +bool kvm_trace_guest_mode_change; + +int kvm_guest_mode_change_trace_reg(void) +{ + kvm_trace_guest_mode_change = 1; + return 0; +} + +void kvm_guest_mode_change_trace_unreg(void) +{ + kvm_trace_guest_mode_change = 0; +} + +/* + * XXXKYMA: We are simulatoring a processor that has the WII bit set in + * Config7, so we are "runnable" if interrupts are pending + */ +int kvm_arch_vcpu_runnable(struct kvm_vcpu *vcpu) +{ + return !!(vcpu->arch.pending_exceptions); +} + +bool kvm_arch_vcpu_in_kernel(struct kvm_vcpu *vcpu) +{ + return false; +} + +int kvm_arch_vcpu_should_kick(struct kvm_vcpu *vcpu) +{ + return 1; +} + +int kvm_arch_hardware_enable(void) +{ + return kvm_mips_callbacks->hardware_enable(); +} + +void kvm_arch_hardware_disable(void) +{ + kvm_mips_callbacks->hardware_disable(); +} + +int kvm_arch_hardware_setup(void) +{ + return 0; +} + +void kvm_arch_check_processor_compat(void *rtn) +{ + *(int *)rtn = 0; +} + +int kvm_arch_init_vm(struct kvm *kvm, unsigned long type) +{ + switch (type) { + case KVM_VM_MIPS_AUTO: + break; +#ifdef CONFIG_KVM_MIPS_VZ + case KVM_VM_MIPS_VZ: +#else + case KVM_VM_MIPS_TE: +#endif + break; + default: + /* Unsupported KVM type */ + return -EINVAL; + }; + + /* Allocate page table to map GPA -> RPA */ + kvm->arch.gpa_mm.pgd = kvm_pgd_alloc(); + if (!kvm->arch.gpa_mm.pgd) + return -ENOMEM; + + return 0; +} + +bool kvm_arch_has_vcpu_debugfs(void) +{ + return false; +} + +int kvm_arch_create_vcpu_debugfs(struct kvm_vcpu *vcpu) +{ + return 0; +} + +void kvm_mips_free_vcpus(struct kvm *kvm) +{ + unsigned int i; + struct kvm_vcpu *vcpu; + + kvm_for_each_vcpu(i, vcpu, kvm) { + kvm_arch_vcpu_free(vcpu); + } + + mutex_lock(&kvm->lock); + + for (i = 0; i < atomic_read(&kvm->online_vcpus); i++) + kvm->vcpus[i] = NULL; + + atomic_set(&kvm->online_vcpus, 0); + + mutex_unlock(&kvm->lock); +} + +static void kvm_mips_free_gpa_pt(struct kvm *kvm) +{ + /* It should always be safe to remove after flushing the whole range */ + WARN_ON(!kvm_mips_flush_gpa_pt(kvm, 0, ~0)); + pgd_free(NULL, kvm->arch.gpa_mm.pgd); +} + +void kvm_arch_destroy_vm(struct kvm *kvm) +{ + kvm_mips_free_vcpus(kvm); + kvm_mips_free_gpa_pt(kvm); +} + +long kvm_arch_dev_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + return -ENOIOCTLCMD; +} + +int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot, + unsigned long npages) +{ + return 0; +} + +void kvm_arch_flush_shadow_all(struct kvm *kvm) +{ + /* Flush whole GPA */ + kvm_mips_flush_gpa_pt(kvm, 0, ~0); + + /* Let implementation do the rest */ + kvm_mips_callbacks->flush_shadow_all(kvm); +} + +void kvm_arch_flush_shadow_memslot(struct kvm *kvm, + struct kvm_memory_slot *slot) +{ + /* + * The slot has been made invalid (ready for moving or deletion), so we + * need to ensure that it can no longer be accessed by any guest VCPUs. + */ + + spin_lock(&kvm->mmu_lock); + /* Flush slot from GPA */ + kvm_mips_flush_gpa_pt(kvm, slot->base_gfn, + slot->base_gfn + slot->npages - 1); + /* Let implementation do the rest */ + kvm_mips_callbacks->flush_shadow_memslot(kvm, slot); + spin_unlock(&kvm->mmu_lock); +} + +int kvm_arch_prepare_memory_region(struct kvm *kvm, + struct kvm_memory_slot *memslot, + const struct kvm_userspace_memory_region *mem, + enum kvm_mr_change change) +{ + return 0; +} + +void kvm_arch_commit_memory_region(struct kvm *kvm, + const struct kvm_userspace_memory_region *mem, + const struct kvm_memory_slot *old, + const struct kvm_memory_slot *new, + enum kvm_mr_change change) +{ + int needs_flush; + + kvm_debug("%s: kvm: %p slot: %d, GPA: %llx, size: %llx, QVA: %llx\n", + __func__, kvm, mem->slot, mem->guest_phys_addr, + mem->memory_size, mem->userspace_addr); + + /* + * If dirty page logging is enabled, write protect all pages in the slot + * ready for dirty logging. + * + * There is no need to do this in any of the following cases: + * CREATE: No dirty mappings will already exist. + * MOVE/DELETE: The old mappings will already have been cleaned up by + * kvm_arch_flush_shadow_memslot() + */ + if (change == KVM_MR_FLAGS_ONLY && + (!(old->flags & KVM_MEM_LOG_DIRTY_PAGES) && + new->flags & KVM_MEM_LOG_DIRTY_PAGES)) { + spin_lock(&kvm->mmu_lock); + /* Write protect GPA page table entries */ + needs_flush = kvm_mips_mkclean_gpa_pt(kvm, new->base_gfn, + new->base_gfn + new->npages - 1); + /* Let implementation do the rest */ + if (needs_flush) + kvm_mips_callbacks->flush_shadow_memslot(kvm, new); + spin_unlock(&kvm->mmu_lock); + } +} + +static inline void dump_handler(const char *symbol, void *start, void *end) +{ + u32 *p; + + pr_debug("LEAF(%s)\n", symbol); + + pr_debug("\t.set push\n"); + pr_debug("\t.set noreorder\n"); + + for (p = start; p < (u32 *)end; ++p) + pr_debug("\t.word\t0x%08x\t\t# %p\n", *p, p); + + pr_debug("\t.set\tpop\n"); + + pr_debug("\tEND(%s)\n", symbol); +} + +struct kvm_vcpu *kvm_arch_vcpu_create(struct kvm *kvm, unsigned int id) +{ + int err, size; + void *gebase, *p, *handler, *refill_start, *refill_end; + int i; + + struct kvm_vcpu *vcpu = kzalloc(sizeof(struct kvm_vcpu), GFP_KERNEL); + + if (!vcpu) { + err = -ENOMEM; + goto out; + } + + err = kvm_vcpu_init(vcpu, kvm, id); + + if (err) + goto out_free_cpu; + + kvm_debug("kvm @ %p: create cpu %d at %p\n", kvm, id, vcpu); + + /* + * Allocate space for host mode exception handlers that handle + * guest mode exits + */ + if (cpu_has_veic || cpu_has_vint) + size = 0x200 + VECTORSPACING * 64; + else + size = 0x4000; + + gebase = kzalloc(ALIGN(size, PAGE_SIZE), GFP_KERNEL); + + if (!gebase) { + err = -ENOMEM; + goto out_uninit_cpu; + } + kvm_debug("Allocated %d bytes for KVM Exception Handlers @ %p\n", + ALIGN(size, PAGE_SIZE), gebase); + + /* + * Check new ebase actually fits in CP0_EBase. The lack of a write gate + * limits us to the low 512MB of physical address space. If the memory + * we allocate is out of range, just give up now. + */ + if (!cpu_has_ebase_wg && virt_to_phys(gebase) >= 0x20000000) { + kvm_err("CP0_EBase.WG required for guest exception base %pK\n", + gebase); + err = -ENOMEM; + goto out_free_gebase; + } + + /* Save new ebase */ + vcpu->arch.guest_ebase = gebase; + + /* Build guest exception vectors dynamically in unmapped memory */ + handler = gebase + 0x2000; + + /* TLB refill (or XTLB refill on 64-bit VZ where KX=1) */ + refill_start = gebase; + if (IS_ENABLED(CONFIG_KVM_MIPS_VZ) && IS_ENABLED(CONFIG_64BIT)) + refill_start += 0x080; + refill_end = kvm_mips_build_tlb_refill_exception(refill_start, handler); + + /* General Exception Entry point */ + kvm_mips_build_exception(gebase + 0x180, handler); + + /* For vectored interrupts poke the exception code @ all offsets 0-7 */ + for (i = 0; i < 8; i++) { + kvm_debug("L1 Vectored handler @ %p\n", + gebase + 0x200 + (i * VECTORSPACING)); + kvm_mips_build_exception(gebase + 0x200 + i * VECTORSPACING, + handler); + } + + /* General exit handler */ + p = handler; + p = kvm_mips_build_exit(p); + + /* Guest entry routine */ + vcpu->arch.vcpu_run = p; + p = kvm_mips_build_vcpu_run(p); + + /* Dump the generated code */ + pr_debug("#include <asm/asm.h>\n"); + pr_debug("#include <asm/regdef.h>\n"); + pr_debug("\n"); + dump_handler("kvm_vcpu_run", vcpu->arch.vcpu_run, p); + dump_handler("kvm_tlb_refill", refill_start, refill_end); + dump_handler("kvm_gen_exc", gebase + 0x180, gebase + 0x200); + dump_handler("kvm_exit", gebase + 0x2000, vcpu->arch.vcpu_run); + + /* Invalidate the icache for these ranges */ + flush_icache_range((unsigned long)gebase, + (unsigned long)gebase + ALIGN(size, PAGE_SIZE)); + + /* + * Allocate comm page for guest kernel, a TLB will be reserved for + * mapping GVA @ 0xFFFF8000 to this page + */ + vcpu->arch.kseg0_commpage = kzalloc(PAGE_SIZE << 1, GFP_KERNEL); + + if (!vcpu->arch.kseg0_commpage) { + err = -ENOMEM; + goto out_free_gebase; + } + + kvm_debug("Allocated COMM page @ %p\n", vcpu->arch.kseg0_commpage); + kvm_mips_commpage_init(vcpu); + + /* Init */ + vcpu->arch.last_sched_cpu = -1; + vcpu->arch.last_exec_cpu = -1; + + return vcpu; + +out_free_gebase: + kfree(gebase); + +out_uninit_cpu: + kvm_vcpu_uninit(vcpu); + +out_free_cpu: + kfree(vcpu); + +out: + return ERR_PTR(err); +} + +void kvm_arch_vcpu_free(struct kvm_vcpu *vcpu) +{ + hrtimer_cancel(&vcpu->arch.comparecount_timer); + + kvm_vcpu_uninit(vcpu); + + kvm_mips_dump_stats(vcpu); + + kvm_mmu_free_memory_caches(vcpu); + kfree(vcpu->arch.guest_ebase); + kfree(vcpu->arch.kseg0_commpage); + kfree(vcpu); +} + +void kvm_arch_vcpu_destroy(struct kvm_vcpu *vcpu) +{ + kvm_arch_vcpu_free(vcpu); +} + +int kvm_arch_vcpu_ioctl_set_guest_debug(struct kvm_vcpu *vcpu, + struct kvm_guest_debug *dbg) +{ + return -ENOIOCTLCMD; +} + +int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run) +{ + int r = -EINTR; + + vcpu_load(vcpu); + + kvm_sigset_activate(vcpu); + + if (vcpu->mmio_needed) { + if (!vcpu->mmio_is_write) + kvm_mips_complete_mmio_load(vcpu, run); + vcpu->mmio_needed = 0; + } + + if (run->immediate_exit) + goto out; + + lose_fpu(1); + + local_irq_disable(); + guest_enter_irqoff(); + trace_kvm_enter(vcpu); + + /* + * Make sure the read of VCPU requests in vcpu_run() callback is not + * reordered ahead of the write to vcpu->mode, or we could miss a TLB + * flush request while the requester sees the VCPU as outside of guest + * mode and not needing an IPI. + */ + smp_store_mb(vcpu->mode, IN_GUEST_MODE); + + r = kvm_mips_callbacks->vcpu_run(run, vcpu); + + trace_kvm_out(vcpu); + guest_exit_irqoff(); + local_irq_enable(); + +out: + kvm_sigset_deactivate(vcpu); + + vcpu_put(vcpu); + return r; +} + +int kvm_vcpu_ioctl_interrupt(struct kvm_vcpu *vcpu, + struct kvm_mips_interrupt *irq) +{ + int intr = (int)irq->irq; + struct kvm_vcpu *dvcpu = NULL; + + if (intr == 3 || intr == -3 || intr == 4 || intr == -4) + kvm_debug("%s: CPU: %d, INTR: %d\n", __func__, irq->cpu, + (int)intr); + + if (irq->cpu == -1) + dvcpu = vcpu; + else + dvcpu = vcpu->kvm->vcpus[irq->cpu]; + + if (intr == 2 || intr == 3 || intr == 4) { + kvm_mips_callbacks->queue_io_int(dvcpu, irq); + + } else if (intr == -2 || intr == -3 || intr == -4) { + kvm_mips_callbacks->dequeue_io_int(dvcpu, irq); + } else { + kvm_err("%s: invalid interrupt ioctl (%d:%d)\n", __func__, + irq->cpu, irq->irq); + return -EINVAL; + } + + dvcpu->arch.wait = 0; + + if (swq_has_sleeper(&dvcpu->wq)) + swake_up_one(&dvcpu->wq); + + return 0; +} + +int kvm_arch_vcpu_ioctl_get_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + return -ENOIOCTLCMD; +} + +int kvm_arch_vcpu_ioctl_set_mpstate(struct kvm_vcpu *vcpu, + struct kvm_mp_state *mp_state) +{ + return -ENOIOCTLCMD; +} + +static u64 kvm_mips_get_one_regs[] = { + KVM_REG_MIPS_R0, + KVM_REG_MIPS_R1, + KVM_REG_MIPS_R2, + KVM_REG_MIPS_R3, + KVM_REG_MIPS_R4, + KVM_REG_MIPS_R5, + KVM_REG_MIPS_R6, + KVM_REG_MIPS_R7, + KVM_REG_MIPS_R8, + KVM_REG_MIPS_R9, + KVM_REG_MIPS_R10, + KVM_REG_MIPS_R11, + KVM_REG_MIPS_R12, + KVM_REG_MIPS_R13, + KVM_REG_MIPS_R14, + KVM_REG_MIPS_R15, + KVM_REG_MIPS_R16, + KVM_REG_MIPS_R17, + KVM_REG_MIPS_R18, + KVM_REG_MIPS_R19, + KVM_REG_MIPS_R20, + KVM_REG_MIPS_R21, + KVM_REG_MIPS_R22, + KVM_REG_MIPS_R23, + KVM_REG_MIPS_R24, + KVM_REG_MIPS_R25, + KVM_REG_MIPS_R26, + KVM_REG_MIPS_R27, + KVM_REG_MIPS_R28, + KVM_REG_MIPS_R29, + KVM_REG_MIPS_R30, + KVM_REG_MIPS_R31, + +#ifndef CONFIG_CPU_MIPSR6 + KVM_REG_MIPS_HI, + KVM_REG_MIPS_LO, +#endif + KVM_REG_MIPS_PC, +}; + +static u64 kvm_mips_get_one_regs_fpu[] = { + KVM_REG_MIPS_FCR_IR, + KVM_REG_MIPS_FCR_CSR, +}; + +static u64 kvm_mips_get_one_regs_msa[] = { + KVM_REG_MIPS_MSA_IR, + KVM_REG_MIPS_MSA_CSR, +}; + +static unsigned long kvm_mips_num_regs(struct kvm_vcpu *vcpu) +{ + unsigned long ret; + + ret = ARRAY_SIZE(kvm_mips_get_one_regs); + if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) { + ret += ARRAY_SIZE(kvm_mips_get_one_regs_fpu) + 48; + /* odd doubles */ + if (boot_cpu_data.fpu_id & MIPS_FPIR_F64) + ret += 16; + } + if (kvm_mips_guest_can_have_msa(&vcpu->arch)) + ret += ARRAY_SIZE(kvm_mips_get_one_regs_msa) + 32; + ret += kvm_mips_callbacks->num_regs(vcpu); + + return ret; +} + +static int kvm_mips_copy_reg_indices(struct kvm_vcpu *vcpu, u64 __user *indices) +{ + u64 index; + unsigned int i; + + if (copy_to_user(indices, kvm_mips_get_one_regs, + sizeof(kvm_mips_get_one_regs))) + return -EFAULT; + indices += ARRAY_SIZE(kvm_mips_get_one_regs); + + if (kvm_mips_guest_can_have_fpu(&vcpu->arch)) { + if (copy_to_user(indices, kvm_mips_get_one_regs_fpu, + sizeof(kvm_mips_get_one_regs_fpu))) + return -EFAULT; + indices += ARRAY_SIZE(kvm_mips_get_one_regs_fpu); + + for (i = 0; i < 32; ++i) { + index = KVM_REG_MIPS_FPR_32(i); + if (copy_to_user(indices, &index, sizeof(index))) + return -EFAULT; + ++indices; + + /* skip odd doubles if no F64 */ + if (i & 1 && !(boot_cpu_data.fpu_id & MIPS_FPIR_F64)) + continue; + + index = KVM_REG_MIPS_FPR_64(i); + if (copy_to_user(indices, &index, sizeof(index))) + return -EFAULT; + ++indices; + } + } + + if (kvm_mips_guest_can_have_msa(&vcpu->arch)) { + if (copy_to_user(indices, kvm_mips_get_one_regs_msa, + sizeof(kvm_mips_get_one_regs_msa))) + return -EFAULT; + indices += ARRAY_SIZE(kvm_mips_get_one_regs_msa); + + for (i = 0; i < 32; ++i) { + index = KVM_REG_MIPS_VEC_128(i); + if (copy_to_user(indices, &index, sizeof(index))) + return -EFAULT; + ++indices; + } + } + + return kvm_mips_callbacks->copy_reg_indices(vcpu, indices); +} + +static int kvm_mips_get_reg(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + struct mips_coproc *cop0 = vcpu->arch.cop0; + struct mips_fpu_struct *fpu = &vcpu->arch.fpu; + int ret; + s64 v; + s64 vs[2]; + unsigned int idx; + + switch (reg->id) { + /* General purpose registers */ + case KVM_REG_MIPS_R0 ... KVM_REG_MIPS_R31: + v = (long)vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0]; + break; +#ifndef CONFIG_CPU_MIPSR6 + case KVM_REG_MIPS_HI: + v = (long)vcpu->arch.hi; + break; + case KVM_REG_MIPS_LO: + v = (long)vcpu->arch.lo; + break; +#endif + case KVM_REG_MIPS_PC: + v = (long)vcpu->arch.pc; + break; + + /* Floating point registers */ + case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31): + if (!kvm_mips_guest_has_fpu(&vcpu->arch)) + return -EINVAL; + idx = reg->id - KVM_REG_MIPS_FPR_32(0); + /* Odd singles in top of even double when FR=0 */ + if (kvm_read_c0_guest_status(cop0) & ST0_FR) + v = get_fpr32(&fpu->fpr[idx], 0); + else + v = get_fpr32(&fpu->fpr[idx & ~1], idx & 1); + break; + case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31): + if (!kvm_mips_guest_has_fpu(&vcpu->arch)) + return -EINVAL; + idx = reg->id - KVM_REG_MIPS_FPR_64(0); + /* Can't access odd doubles in FR=0 mode */ + if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR)) + return -EINVAL; + v = get_fpr64(&fpu->fpr[idx], 0); + break; + case KVM_REG_MIPS_FCR_IR: + if (!kvm_mips_guest_has_fpu(&vcpu->arch)) + return -EINVAL; + v = boot_cpu_data.fpu_id; + break; + case KVM_REG_MIPS_FCR_CSR: + if (!kvm_mips_guest_has_fpu(&vcpu->arch)) + return -EINVAL; + v = fpu->fcr31; + break; + + /* MIPS SIMD Architecture (MSA) registers */ + case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31): + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + /* Can't access MSA registers in FR=0 mode */ + if (!(kvm_read_c0_guest_status(cop0) & ST0_FR)) + return -EINVAL; + idx = reg->id - KVM_REG_MIPS_VEC_128(0); +#ifdef CONFIG_CPU_LITTLE_ENDIAN + /* least significant byte first */ + vs[0] = get_fpr64(&fpu->fpr[idx], 0); + vs[1] = get_fpr64(&fpu->fpr[idx], 1); +#else + /* most significant byte first */ + vs[0] = get_fpr64(&fpu->fpr[idx], 1); + vs[1] = get_fpr64(&fpu->fpr[idx], 0); +#endif + break; + case KVM_REG_MIPS_MSA_IR: + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + v = boot_cpu_data.msa_id; + break; + case KVM_REG_MIPS_MSA_CSR: + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + v = fpu->msacsr; + break; + + /* registers to be handled specially */ + default: + ret = kvm_mips_callbacks->get_one_reg(vcpu, reg, &v); + if (ret) + return ret; + break; + } + if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) { + u64 __user *uaddr64 = (u64 __user *)(long)reg->addr; + + return put_user(v, uaddr64); + } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) { + u32 __user *uaddr32 = (u32 __user *)(long)reg->addr; + u32 v32 = (u32)v; + + return put_user(v32, uaddr32); + } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) { + void __user *uaddr = (void __user *)(long)reg->addr; + + return copy_to_user(uaddr, vs, 16) ? -EFAULT : 0; + } else { + return -EINVAL; + } +} + +static int kvm_mips_set_reg(struct kvm_vcpu *vcpu, + const struct kvm_one_reg *reg) +{ + struct mips_coproc *cop0 = vcpu->arch.cop0; + struct mips_fpu_struct *fpu = &vcpu->arch.fpu; + s64 v; + s64 vs[2]; + unsigned int idx; + + if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U64) { + u64 __user *uaddr64 = (u64 __user *)(long)reg->addr; + + if (get_user(v, uaddr64) != 0) + return -EFAULT; + } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U32) { + u32 __user *uaddr32 = (u32 __user *)(long)reg->addr; + s32 v32; + + if (get_user(v32, uaddr32) != 0) + return -EFAULT; + v = (s64)v32; + } else if ((reg->id & KVM_REG_SIZE_MASK) == KVM_REG_SIZE_U128) { + void __user *uaddr = (void __user *)(long)reg->addr; + + return copy_from_user(vs, uaddr, 16) ? -EFAULT : 0; + } else { + return -EINVAL; + } + + switch (reg->id) { + /* General purpose registers */ + case KVM_REG_MIPS_R0: + /* Silently ignore requests to set $0 */ + break; + case KVM_REG_MIPS_R1 ... KVM_REG_MIPS_R31: + vcpu->arch.gprs[reg->id - KVM_REG_MIPS_R0] = v; + break; +#ifndef CONFIG_CPU_MIPSR6 + case KVM_REG_MIPS_HI: + vcpu->arch.hi = v; + break; + case KVM_REG_MIPS_LO: + vcpu->arch.lo = v; + break; +#endif + case KVM_REG_MIPS_PC: + vcpu->arch.pc = v; + break; + + /* Floating point registers */ + case KVM_REG_MIPS_FPR_32(0) ... KVM_REG_MIPS_FPR_32(31): + if (!kvm_mips_guest_has_fpu(&vcpu->arch)) + return -EINVAL; + idx = reg->id - KVM_REG_MIPS_FPR_32(0); + /* Odd singles in top of even double when FR=0 */ + if (kvm_read_c0_guest_status(cop0) & ST0_FR) + set_fpr32(&fpu->fpr[idx], 0, v); + else + set_fpr32(&fpu->fpr[idx & ~1], idx & 1, v); + break; + case KVM_REG_MIPS_FPR_64(0) ... KVM_REG_MIPS_FPR_64(31): + if (!kvm_mips_guest_has_fpu(&vcpu->arch)) + return -EINVAL; + idx = reg->id - KVM_REG_MIPS_FPR_64(0); + /* Can't access odd doubles in FR=0 mode */ + if (idx & 1 && !(kvm_read_c0_guest_status(cop0) & ST0_FR)) + return -EINVAL; + set_fpr64(&fpu->fpr[idx], 0, v); + break; + case KVM_REG_MIPS_FCR_IR: + if (!kvm_mips_guest_has_fpu(&vcpu->arch)) + return -EINVAL; + /* Read-only */ + break; + case KVM_REG_MIPS_FCR_CSR: + if (!kvm_mips_guest_has_fpu(&vcpu->arch)) + return -EINVAL; + fpu->fcr31 = v; + break; + + /* MIPS SIMD Architecture (MSA) registers */ + case KVM_REG_MIPS_VEC_128(0) ... KVM_REG_MIPS_VEC_128(31): + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + idx = reg->id - KVM_REG_MIPS_VEC_128(0); +#ifdef CONFIG_CPU_LITTLE_ENDIAN + /* least significant byte first */ + set_fpr64(&fpu->fpr[idx], 0, vs[0]); + set_fpr64(&fpu->fpr[idx], 1, vs[1]); +#else + /* most significant byte first */ + set_fpr64(&fpu->fpr[idx], 1, vs[0]); + set_fpr64(&fpu->fpr[idx], 0, vs[1]); +#endif + break; + case KVM_REG_MIPS_MSA_IR: + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + /* Read-only */ + break; + case KVM_REG_MIPS_MSA_CSR: + if (!kvm_mips_guest_has_msa(&vcpu->arch)) + return -EINVAL; + fpu->msacsr = v; + break; + + /* registers to be handled specially */ + default: + return kvm_mips_callbacks->set_one_reg(vcpu, reg, v); + } + return 0; +} + +static int kvm_vcpu_ioctl_enable_cap(struct kvm_vcpu *vcpu, + struct kvm_enable_cap *cap) +{ + int r = 0; + + if (!kvm_vm_ioctl_check_extension(vcpu->kvm, cap->cap)) + return -EINVAL; + if (cap->flags) + return -EINVAL; + if (cap->args[0]) + return -EINVAL; + + switch (cap->cap) { + case KVM_CAP_MIPS_FPU: + vcpu->arch.fpu_enabled = true; + break; + case KVM_CAP_MIPS_MSA: + vcpu->arch.msa_enabled = true; + break; + default: + r = -EINVAL; + break; + } + + return r; +} + +long kvm_arch_vcpu_async_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + struct kvm_vcpu *vcpu = filp->private_data; + void __user *argp = (void __user *)arg; + + if (ioctl == KVM_INTERRUPT) { + struct kvm_mips_interrupt irq; + + if (copy_from_user(&irq, argp, sizeof(irq))) + return -EFAULT; + kvm_debug("[%d] %s: irq: %d\n", vcpu->vcpu_id, __func__, + irq.irq); + + return kvm_vcpu_ioctl_interrupt(vcpu, &irq); + } + + return -ENOIOCTLCMD; +} + +long kvm_arch_vcpu_ioctl(struct file *filp, unsigned int ioctl, + unsigned long arg) +{ + struct kvm_vcpu *vcpu = filp->private_data; + void __user *argp = (void __user *)arg; + long r; + + vcpu_load(vcpu); + + switch (ioctl) { + case KVM_SET_ONE_REG: + case KVM_GET_ONE_REG: { + struct kvm_one_reg reg; + + r = -EFAULT; + if (copy_from_user(®, argp, sizeof(reg))) + break; + if (ioctl == KVM_SET_ONE_REG) + r = kvm_mips_set_reg(vcpu, ®); + else + r = kvm_mips_get_reg(vcpu, ®); + break; + } + case KVM_GET_REG_LIST: { + struct kvm_reg_list __user *user_list = argp; + struct kvm_reg_list reg_list; + unsigned n; + + r = -EFAULT; + if (copy_from_user(®_list, user_list, sizeof(reg_list))) + break; + n = reg_list.n; + reg_list.n = kvm_mips_num_regs(vcpu); + if (copy_to_user(user_list, ®_list, sizeof(reg_list))) + break; + r = -E2BIG; + if (n < reg_list.n) + break; + r = kvm_mips_copy_reg_indices(vcpu, user_list->reg); + break; + } + case KVM_ENABLE_CAP: { + struct kvm_enable_cap cap; + + r = -EFAULT; + if (copy_from_user(&cap, argp, sizeof(cap))) + break; + r = kvm_vcpu_ioctl_enable_cap(vcpu, &cap); + break; + } + default: + r = -ENOIOCTLCMD; + } + + vcpu_put(vcpu); + return r; +} + +/** + * kvm_vm_ioctl_get_dirty_log - get and clear the log of dirty pages in a slot + * @kvm: kvm instance + * @log: slot id and address to which we copy the log + * + * Steps 1-4 below provide general overview of dirty page logging. See + * kvm_get_dirty_log_protect() function description for additional details. + * + * We call kvm_get_dirty_log_protect() to handle steps 1-3, upon return we + * always flush the TLB (step 4) even if previous step failed and the dirty + * bitmap may be corrupt. Regardless of previous outcome the KVM logging API + * does not preclude user space subsequent dirty log read. Flushing TLB ensures + * writes will be marked dirty for next log read. + * + * 1. Take a snapshot of the bit and clear it if needed. + * 2. Write protect the corresponding page. + * 3. Copy the snapshot to the userspace. + * 4. Flush TLB's if needed. + */ +int kvm_vm_ioctl_get_dirty_log(struct kvm *kvm, struct kvm_dirty_log *log) +{ + struct kvm_memslots *slots; + struct kvm_memory_slot *memslot; + bool is_dirty = false; + int r; + + mutex_lock(&kvm->slots_lock); + + r = kvm_get_dirty_log_protect(kvm, log, &is_dirty); + + if (is_dirty) { + slots = kvm_memslots(kvm); + memslot = id_to_memslot(slots, log->slot); + + /* Let implementation handle TLB/GVA invalidation */ + kvm_mips_callbacks->flush_shadow_memslot(kvm, memslot); + } + + mutex_unlock(&kvm->slots_lock); + return r; +} + +long kvm_arch_vm_ioctl(struct file *filp, unsigned int ioctl, unsigned long arg) +{ + long r; + + switch (ioctl) { + default: + r = -ENOIOCTLCMD; + } + + return r; +} + +int kvm_arch_init(void *opaque) +{ + if (kvm_mips_callbacks) { + kvm_err("kvm: module already exists\n"); + return -EEXIST; + } + + return kvm_mips_emulation_init(&kvm_mips_callbacks); +} + +void kvm_arch_exit(void) +{ + kvm_mips_callbacks = NULL; +} + +int kvm_arch_vcpu_ioctl_get_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs) +{ + return -ENOIOCTLCMD; +} + +int kvm_arch_vcpu_ioctl_set_sregs(struct kvm_vcpu *vcpu, + struct kvm_sregs *sregs) +{ + return -ENOIOCTLCMD; +} + +void kvm_arch_vcpu_postcreate(struct kvm_vcpu *vcpu) +{ +} + +int kvm_arch_vcpu_ioctl_get_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) +{ + return -ENOIOCTLCMD; +} + +int kvm_arch_vcpu_ioctl_set_fpu(struct kvm_vcpu *vcpu, struct kvm_fpu *fpu) +{ + return -ENOIOCTLCMD; +} + +vm_fault_t kvm_arch_vcpu_fault(struct kvm_vcpu *vcpu, struct vm_fault *vmf) +{ + return VM_FAULT_SIGBUS; +} + +int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) +{ + int r; + + switch (ext) { + case KVM_CAP_ONE_REG: + case KVM_CAP_ENABLE_CAP: + case KVM_CAP_READONLY_MEM: + case KVM_CAP_SYNC_MMU: + case KVM_CAP_IMMEDIATE_EXIT: + r = 1; + break; + case KVM_CAP_NR_VCPUS: + r = num_online_cpus(); + break; + case KVM_CAP_MAX_VCPUS: + r = KVM_MAX_VCPUS; + break; + case KVM_CAP_MAX_VCPU_ID: + r = KVM_MAX_VCPU_ID; + break; + case KVM_CAP_MIPS_FPU: + /* We don't handle systems with inconsistent cpu_has_fpu */ + r = !!raw_cpu_has_fpu; + break; + case KVM_CAP_MIPS_MSA: + /* + * We don't support MSA vector partitioning yet: + * 1) It would require explicit support which can't be tested + * yet due to lack of support in current hardware. + * 2) It extends the state that would need to be saved/restored + * by e.g. QEMU for migration. + * + * When vector partitioning hardware becomes available, support + * could be added by requiring a flag when enabling + * KVM_CAP_MIPS_MSA capability to indicate that userland knows + * to save/restore the appropriate extra state. + */ + r = cpu_has_msa && !(boot_cpu_data.msa_id & MSA_IR_WRPF); + break; + default: + r = kvm_mips_callbacks->check_extension(kvm, ext); + break; + } + return r; +} + +int kvm_cpu_has_pending_timer(struct kvm_vcpu *vcpu) +{ + return kvm_mips_pending_timer(vcpu) || + kvm_read_c0_guest_cause(vcpu->arch.cop0) & C_TI; +} + +int kvm_arch_vcpu_dump_regs(struct kvm_vcpu *vcpu) +{ + int i; + struct mips_coproc *cop0; + + if (!vcpu) + return -1; + + kvm_debug("VCPU Register Dump:\n"); + kvm_debug("\tpc = 0x%08lx\n", vcpu->arch.pc); + kvm_debug("\texceptions: %08lx\n", vcpu->arch.pending_exceptions); + + for (i = 0; i < 32; i += 4) { + kvm_debug("\tgpr%02d: %08lx %08lx %08lx %08lx\n", i, + vcpu->arch.gprs[i], + vcpu->arch.gprs[i + 1], + vcpu->arch.gprs[i + 2], vcpu->arch.gprs[i + 3]); + } + kvm_debug("\thi: 0x%08lx\n", vcpu->arch.hi); + kvm_debug("\tlo: 0x%08lx\n", vcpu->arch.lo); + + cop0 = vcpu->arch.cop0; + kvm_debug("\tStatus: 0x%08x, Cause: 0x%08x\n", + kvm_read_c0_guest_status(cop0), + kvm_read_c0_guest_cause(cop0)); + + kvm_debug("\tEPC: 0x%08lx\n", kvm_read_c0_guest_epc(cop0)); + + return 0; +} + +int kvm_arch_vcpu_ioctl_set_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) +{ + int i; + + vcpu_load(vcpu); + + for (i = 1; i < ARRAY_SIZE(vcpu->arch.gprs); i++) + vcpu->arch.gprs[i] = regs->gpr[i]; + vcpu->arch.gprs[0] = 0; /* zero is special, and cannot be set. */ + vcpu->arch.hi = regs->hi; + vcpu->arch.lo = regs->lo; + vcpu->arch.pc = regs->pc; + + vcpu_put(vcpu); + return 0; +} + +int kvm_arch_vcpu_ioctl_get_regs(struct kvm_vcpu *vcpu, struct kvm_regs *regs) +{ + int i; + + vcpu_load(vcpu); + + for (i = 0; i < ARRAY_SIZE(vcpu->arch.gprs); i++) + regs->gpr[i] = vcpu->arch.gprs[i]; + + regs->hi = vcpu->arch.hi; + regs->lo = vcpu->arch.lo; + regs->pc = vcpu->arch.pc; + + vcpu_put(vcpu); + return 0; +} + +static void kvm_mips_comparecount_func(unsigned long data) +{ + struct kvm_vcpu *vcpu = (struct kvm_vcpu *)data; + + kvm_mips_callbacks->queue_timer_int(vcpu); + + vcpu->arch.wait = 0; + if (swq_has_sleeper(&vcpu->wq)) + swake_up_one(&vcpu->wq); +} + +/* low level hrtimer wake routine */ +static enum hrtimer_restart kvm_mips_comparecount_wakeup(struct hrtimer *timer) +{ + struct kvm_vcpu *vcpu; + + vcpu = container_of(timer, struct kvm_vcpu, arch.comparecount_timer); + kvm_mips_comparecount_func((unsigned long) vcpu); + return kvm_mips_count_timeout(vcpu); +} + +int kvm_arch_vcpu_init(struct kvm_vcpu *vcpu) +{ + int err; + + err = kvm_mips_callbacks->vcpu_init(vcpu); + if (err) + return err; + + hrtimer_init(&vcpu->arch.comparecount_timer, CLOCK_MONOTONIC, + HRTIMER_MODE_REL); + vcpu->arch.comparecount_timer.function = kvm_mips_comparecount_wakeup; + return 0; +} + +void kvm_arch_vcpu_uninit(struct kvm_vcpu *vcpu) +{ + kvm_mips_callbacks->vcpu_uninit(vcpu); +} + +int kvm_arch_vcpu_ioctl_translate(struct kvm_vcpu *vcpu, + struct kvm_translation *tr) +{ + return 0; +} + +/* Initial guest state */ +int kvm_arch_vcpu_setup(struct kvm_vcpu *vcpu) +{ + return kvm_mips_callbacks->vcpu_setup(vcpu); +} + +static void kvm_mips_set_c0_status(void) +{ + u32 status = read_c0_status(); + + if (cpu_has_dsp) + status |= (ST0_MX); + + write_c0_status(status); + ehb(); +} + +/* + * Return value is in the form (errcode<<2 | RESUME_FLAG_HOST | RESUME_FLAG_NV) + */ +int kvm_mips_handle_exit(struct kvm_run *run, struct kvm_vcpu *vcpu) +{ + u32 cause = vcpu->arch.host_cp0_cause; + u32 exccode = (cause >> CAUSEB_EXCCODE) & 0x1f; + u32 __user *opc = (u32 __user *) vcpu->arch.pc; + unsigned long badvaddr = vcpu->arch.host_cp0_badvaddr; + enum emulation_result er = EMULATE_DONE; + u32 inst; + int ret = RESUME_GUEST; + + vcpu->mode = OUTSIDE_GUEST_MODE; + + /* re-enable HTW before enabling interrupts */ + if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) + htw_start(); + + /* Set a default exit reason */ + run->exit_reason = KVM_EXIT_UNKNOWN; + run->ready_for_interrupt_injection = 1; + + /* + * Set the appropriate status bits based on host CPU features, + * before we hit the scheduler + */ + kvm_mips_set_c0_status(); + + local_irq_enable(); + + kvm_debug("kvm_mips_handle_exit: cause: %#x, PC: %p, kvm_run: %p, kvm_vcpu: %p\n", + cause, opc, run, vcpu); + trace_kvm_exit(vcpu, exccode); + + if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) { + /* + * Do a privilege check, if in UM most of these exit conditions + * end up causing an exception to be delivered to the Guest + * Kernel + */ + er = kvm_mips_check_privilege(cause, opc, run, vcpu); + if (er == EMULATE_PRIV_FAIL) { + goto skip_emul; + } else if (er == EMULATE_FAIL) { + run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + ret = RESUME_HOST; + goto skip_emul; + } + } + + switch (exccode) { + case EXCCODE_INT: + kvm_debug("[%d]EXCCODE_INT @ %p\n", vcpu->vcpu_id, opc); + + ++vcpu->stat.int_exits; + + if (need_resched()) + cond_resched(); + + ret = RESUME_GUEST; + break; + + case EXCCODE_CPU: + kvm_debug("EXCCODE_CPU: @ PC: %p\n", opc); + + ++vcpu->stat.cop_unusable_exits; + ret = kvm_mips_callbacks->handle_cop_unusable(vcpu); + /* XXXKYMA: Might need to return to user space */ + if (run->exit_reason == KVM_EXIT_IRQ_WINDOW_OPEN) + ret = RESUME_HOST; + break; + + case EXCCODE_MOD: + ++vcpu->stat.tlbmod_exits; + ret = kvm_mips_callbacks->handle_tlb_mod(vcpu); + break; + + case EXCCODE_TLBS: + kvm_debug("TLB ST fault: cause %#x, status %#x, PC: %p, BadVaddr: %#lx\n", + cause, kvm_read_c0_guest_status(vcpu->arch.cop0), opc, + badvaddr); + + ++vcpu->stat.tlbmiss_st_exits; + ret = kvm_mips_callbacks->handle_tlb_st_miss(vcpu); + break; + + case EXCCODE_TLBL: + kvm_debug("TLB LD fault: cause %#x, PC: %p, BadVaddr: %#lx\n", + cause, opc, badvaddr); + + ++vcpu->stat.tlbmiss_ld_exits; + ret = kvm_mips_callbacks->handle_tlb_ld_miss(vcpu); + break; + + case EXCCODE_ADES: + ++vcpu->stat.addrerr_st_exits; + ret = kvm_mips_callbacks->handle_addr_err_st(vcpu); + break; + + case EXCCODE_ADEL: + ++vcpu->stat.addrerr_ld_exits; + ret = kvm_mips_callbacks->handle_addr_err_ld(vcpu); + break; + + case EXCCODE_SYS: + ++vcpu->stat.syscall_exits; + ret = kvm_mips_callbacks->handle_syscall(vcpu); + break; + + case EXCCODE_RI: + ++vcpu->stat.resvd_inst_exits; + ret = kvm_mips_callbacks->handle_res_inst(vcpu); + break; + + case EXCCODE_BP: + ++vcpu->stat.break_inst_exits; + ret = kvm_mips_callbacks->handle_break(vcpu); + break; + + case EXCCODE_TR: + ++vcpu->stat.trap_inst_exits; + ret = kvm_mips_callbacks->handle_trap(vcpu); + break; + + case EXCCODE_MSAFPE: + ++vcpu->stat.msa_fpe_exits; + ret = kvm_mips_callbacks->handle_msa_fpe(vcpu); + break; + + case EXCCODE_FPE: + ++vcpu->stat.fpe_exits; + ret = kvm_mips_callbacks->handle_fpe(vcpu); + break; + + case EXCCODE_MSADIS: + ++vcpu->stat.msa_disabled_exits; + ret = kvm_mips_callbacks->handle_msa_disabled(vcpu); + break; + + case EXCCODE_GE: + /* defer exit accounting to handler */ + ret = kvm_mips_callbacks->handle_guest_exit(vcpu); + break; + + default: + if (cause & CAUSEF_BD) + opc += 1; + inst = 0; + kvm_get_badinstr(opc, vcpu, &inst); + kvm_err("Exception Code: %d, not yet handled, @ PC: %p, inst: 0x%08x BadVaddr: %#lx Status: %#x\n", + exccode, opc, inst, badvaddr, + kvm_read_c0_guest_status(vcpu->arch.cop0)); + kvm_arch_vcpu_dump_regs(vcpu); + run->exit_reason = KVM_EXIT_INTERNAL_ERROR; + ret = RESUME_HOST; + break; + + } + +skip_emul: + local_irq_disable(); + + if (ret == RESUME_GUEST) + kvm_vz_acquire_htimer(vcpu); + + if (er == EMULATE_DONE && !(ret & RESUME_HOST)) + kvm_mips_deliver_interrupts(vcpu, cause); + + if (!(ret & RESUME_HOST)) { + /* Only check for signals if not already exiting to userspace */ + if (signal_pending(current)) { + run->exit_reason = KVM_EXIT_INTR; + ret = (-EINTR << 2) | RESUME_HOST; + ++vcpu->stat.signal_exits; + trace_kvm_exit(vcpu, KVM_TRACE_EXIT_SIGNAL); + } + } + + if (ret == RESUME_GUEST) { + trace_kvm_reenter(vcpu); + + /* + * Make sure the read of VCPU requests in vcpu_reenter() + * callback is not reordered ahead of the write to vcpu->mode, + * or we could miss a TLB flush request while the requester sees + * the VCPU as outside of guest mode and not needing an IPI. + */ + smp_store_mb(vcpu->mode, IN_GUEST_MODE); + + kvm_mips_callbacks->vcpu_reenter(run, vcpu); + + /* + * If FPU / MSA are enabled (i.e. the guest's FPU / MSA context + * is live), restore FCR31 / MSACSR. + * + * This should be before returning to the guest exception + * vector, as it may well cause an [MSA] FP exception if there + * are pending exception bits unmasked. (see + * kvm_mips_csr_die_notifier() for how that is handled). + */ + if (kvm_mips_guest_has_fpu(&vcpu->arch) && + read_c0_status() & ST0_CU1) + __kvm_restore_fcsr(&vcpu->arch); + + if (kvm_mips_guest_has_msa(&vcpu->arch) && + read_c0_config5() & MIPS_CONF5_MSAEN) + __kvm_restore_msacsr(&vcpu->arch); + } + + /* Disable HTW before returning to guest or host */ + if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) + htw_stop(); + + return ret; +} + +/* Enable FPU for guest and restore context */ +void kvm_own_fpu(struct kvm_vcpu *vcpu) +{ + struct mips_coproc *cop0 = vcpu->arch.cop0; + unsigned int sr, cfg5; + + preempt_disable(); + + sr = kvm_read_c0_guest_status(cop0); + + /* + * If MSA state is already live, it is undefined how it interacts with + * FR=0 FPU state, and we don't want to hit reserved instruction + * exceptions trying to save the MSA state later when CU=1 && FR=1, so + * play it safe and save it first. + * + * In theory we shouldn't ever hit this case since kvm_lose_fpu() should + * get called when guest CU1 is set, however we can't trust the guest + * not to clobber the status register directly via the commpage. + */ + if (cpu_has_msa && sr & ST0_CU1 && !(sr & ST0_FR) && + vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) + kvm_lose_fpu(vcpu); + + /* + * Enable FPU for guest + * We set FR and FRE according to guest context + */ + change_c0_status(ST0_CU1 | ST0_FR, sr); + if (cpu_has_fre) { + cfg5 = kvm_read_c0_guest_config5(cop0); + change_c0_config5(MIPS_CONF5_FRE, cfg5); + } + enable_fpu_hazard(); + + /* If guest FPU state not active, restore it now */ + if (!(vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU)) { + __kvm_restore_fpu(&vcpu->arch); + vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU; + trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_FPU); + } else { + trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_FPU); + } + + preempt_enable(); +} + +#ifdef CONFIG_CPU_HAS_MSA +/* Enable MSA for guest and restore context */ +void kvm_own_msa(struct kvm_vcpu *vcpu) +{ + struct mips_coproc *cop0 = vcpu->arch.cop0; + unsigned int sr, cfg5; + + preempt_disable(); + + /* + * Enable FPU if enabled in guest, since we're restoring FPU context + * anyway. We set FR and FRE according to guest context. + */ + if (kvm_mips_guest_has_fpu(&vcpu->arch)) { + sr = kvm_read_c0_guest_status(cop0); + + /* + * If FR=0 FPU state is already live, it is undefined how it + * interacts with MSA state, so play it safe and save it first. + */ + if (!(sr & ST0_FR) && + (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | + KVM_MIPS_AUX_MSA)) == KVM_MIPS_AUX_FPU) + kvm_lose_fpu(vcpu); + + change_c0_status(ST0_CU1 | ST0_FR, sr); + if (sr & ST0_CU1 && cpu_has_fre) { + cfg5 = kvm_read_c0_guest_config5(cop0); + change_c0_config5(MIPS_CONF5_FRE, cfg5); + } + } + + /* Enable MSA for guest */ + set_c0_config5(MIPS_CONF5_MSAEN); + enable_fpu_hazard(); + + switch (vcpu->arch.aux_inuse & (KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA)) { + case KVM_MIPS_AUX_FPU: + /* + * Guest FPU state already loaded, only restore upper MSA state + */ + __kvm_restore_msa_upper(&vcpu->arch); + vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA; + trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, KVM_TRACE_AUX_MSA); + break; + case 0: + /* Neither FPU or MSA already active, restore full MSA state */ + __kvm_restore_msa(&vcpu->arch); + vcpu->arch.aux_inuse |= KVM_MIPS_AUX_MSA; + if (kvm_mips_guest_has_fpu(&vcpu->arch)) + vcpu->arch.aux_inuse |= KVM_MIPS_AUX_FPU; + trace_kvm_aux(vcpu, KVM_TRACE_AUX_RESTORE, + KVM_TRACE_AUX_FPU_MSA); + break; + default: + trace_kvm_aux(vcpu, KVM_TRACE_AUX_ENABLE, KVM_TRACE_AUX_MSA); + break; + } + + preempt_enable(); +} +#endif + +/* Drop FPU & MSA without saving it */ +void kvm_drop_fpu(struct kvm_vcpu *vcpu) +{ + preempt_disable(); + if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) { + disable_msa(); + trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_MSA); + vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_MSA; + } + if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) { + clear_c0_status(ST0_CU1 | ST0_FR); + trace_kvm_aux(vcpu, KVM_TRACE_AUX_DISCARD, KVM_TRACE_AUX_FPU); + vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU; + } + preempt_enable(); +} + +/* Save and disable FPU & MSA */ +void kvm_lose_fpu(struct kvm_vcpu *vcpu) +{ + /* + * With T&E, FPU & MSA get disabled in root context (hardware) when it + * is disabled in guest context (software), but the register state in + * the hardware may still be in use. + * This is why we explicitly re-enable the hardware before saving. + */ + + preempt_disable(); + if (cpu_has_msa && vcpu->arch.aux_inuse & KVM_MIPS_AUX_MSA) { + if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) { + set_c0_config5(MIPS_CONF5_MSAEN); + enable_fpu_hazard(); + } + + __kvm_save_msa(&vcpu->arch); + trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU_MSA); + + /* Disable MSA & FPU */ + disable_msa(); + if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) { + clear_c0_status(ST0_CU1 | ST0_FR); + disable_fpu_hazard(); + } + vcpu->arch.aux_inuse &= ~(KVM_MIPS_AUX_FPU | KVM_MIPS_AUX_MSA); + } else if (vcpu->arch.aux_inuse & KVM_MIPS_AUX_FPU) { + if (!IS_ENABLED(CONFIG_KVM_MIPS_VZ)) { + set_c0_status(ST0_CU1); + enable_fpu_hazard(); + } + + __kvm_save_fpu(&vcpu->arch); + vcpu->arch.aux_inuse &= ~KVM_MIPS_AUX_FPU; + trace_kvm_aux(vcpu, KVM_TRACE_AUX_SAVE, KVM_TRACE_AUX_FPU); + + /* Disable FPU */ + clear_c0_status(ST0_CU1 | ST0_FR); + disable_fpu_hazard(); + } + preempt_enable(); +} + +/* + * Step over a specific ctc1 to FCSR and a specific ctcmsa to MSACSR which are + * used to restore guest FCSR/MSACSR state and may trigger a "harmless" FP/MSAFP + * exception if cause bits are set in the value being written. + */ +static int kvm_mips_csr_die_notify(struct notifier_block *self, + unsigned long cmd, void *ptr) +{ + struct die_args *args = (struct die_args *)ptr; + struct pt_regs *regs = args->regs; + unsigned long pc; + + /* Only interested in FPE and MSAFPE */ + if (cmd != DIE_FP && cmd != DIE_MSAFP) + return NOTIFY_DONE; + + /* Return immediately if guest context isn't active */ + if (!(current->flags & PF_VCPU)) + return NOTIFY_DONE; + + /* Should never get here from user mode */ + BUG_ON(user_mode(regs)); + + pc = instruction_pointer(regs); + switch (cmd) { + case DIE_FP: + /* match 2nd instruction in __kvm_restore_fcsr */ + if (pc != (unsigned long)&__kvm_restore_fcsr + 4) + return NOTIFY_DONE; + break; + case DIE_MSAFP: + /* match 2nd/3rd instruction in __kvm_restore_msacsr */ + if (!cpu_has_msa || + pc < (unsigned long)&__kvm_restore_msacsr + 4 || + pc > (unsigned long)&__kvm_restore_msacsr + 8) + return NOTIFY_DONE; + break; + } + + /* Move PC forward a little and continue executing */ + instruction_pointer(regs) += 4; + + return NOTIFY_STOP; +} + +static struct notifier_block kvm_mips_csr_die_notifier = { + .notifier_call = kvm_mips_csr_die_notify, +}; + +static int __init kvm_mips_init(void) +{ + int ret; + + ret = kvm_mips_entry_setup(); + if (ret) + return ret; + + ret = kvm_init(NULL, sizeof(struct kvm_vcpu), 0, THIS_MODULE); + + if (ret) + return ret; + + register_die_notifier(&kvm_mips_csr_die_notifier); + + return 0; +} + +static void __exit kvm_mips_exit(void) +{ + kvm_exit(); + + unregister_die_notifier(&kvm_mips_csr_die_notifier); +} + +module_init(kvm_mips_init); +module_exit(kvm_mips_exit); + +EXPORT_TRACEPOINT_SYMBOL(kvm_exit); |