[linux-2.6-block.git] / arch / mips / kvm / mmu.c

/*
 * 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 MMU handling in the KVM module.
 *
 * Copyright (C) 2012  MIPS Technologies, Inc.  All rights reserved.
 * Authors: Sanjay Lal <sanjayl@kymasys.com>
 */

#include <linux/kvm_host.h>
#include <asm/mmu_context.h>

static u32 kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu)
{
	int cpu = smp_processor_id();

	return vcpu->arch.guest_kernel_asid[cpu] &
			cpu_asid_mask(&cpu_data[cpu]);
}

static u32 kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
{
	int cpu = smp_processor_id();

	return vcpu->arch.guest_user_asid[cpu] &
			cpu_asid_mask(&cpu_data[cpu]);
}

static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
{
	int srcu_idx, err = 0;
	kvm_pfn_t pfn;

	if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE)
		return 0;

	srcu_idx = srcu_read_lock(&kvm->srcu);
	pfn = gfn_to_pfn(kvm, gfn);

	if (is_error_pfn(pfn)) {
		kvm_err("Couldn't get pfn for gfn %#llx!\n", gfn);
		err = -EFAULT;
		goto out;
	}

	kvm->arch.guest_pmap[gfn] = pfn;
out:
	srcu_read_unlock(&kvm->srcu, srcu_idx);
	return err;
}

/* Translate guest KSEG0 addresses to Host PA */
unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu,
						    unsigned long gva)
{
	gfn_t gfn;
	unsigned long offset = gva & ~PAGE_MASK;
	struct kvm *kvm = vcpu->kvm;

	if (KVM_GUEST_KSEGX(gva) != KVM_GUEST_KSEG0) {
		kvm_err("%s/%p: Invalid gva: %#lx\n", __func__,
			__builtin_return_address(0), gva);
		return KVM_INVALID_PAGE;
	}

	gfn = (KVM_GUEST_CPHYSADDR(gva) >> PAGE_SHIFT);

	if (gfn >= kvm->arch.guest_pmap_npages) {
		kvm_err("%s: Invalid gfn: %#llx, GVA: %#lx\n", __func__, gfn,
			gva);
		return KVM_INVALID_PAGE;
	}

	if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
		return KVM_INVALID_ADDR;

	return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset;
}

/* XXXKYMA: Must be called with interrupts disabled */
int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr,
				    struct kvm_vcpu *vcpu)
{
	gfn_t gfn;
	kvm_pfn_t pfn0, pfn1;
	unsigned long vaddr = 0;
	unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
	struct kvm *kvm = vcpu->kvm;
	const int flush_dcache_mask = 0;
	int ret;

	if (KVM_GUEST_KSEGX(badvaddr) != KVM_GUEST_KSEG0) {
		kvm_err("%s: Invalid BadVaddr: %#lx\n", __func__, badvaddr);
		kvm_mips_dump_host_tlbs();
		return -1;
	}

	gfn = (KVM_GUEST_CPHYSADDR(badvaddr) >> PAGE_SHIFT);
	if (gfn >= kvm->arch.guest_pmap_npages) {
		kvm_err("%s: Invalid gfn: %#llx, BadVaddr: %#lx\n", __func__,
			gfn, badvaddr);
		kvm_mips_dump_host_tlbs();
		return -1;
	}
	vaddr = badvaddr & (PAGE_MASK << 1);

	if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
		return -1;

	if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0)
		return -1;

	pfn0 = kvm->arch.guest_pmap[gfn & ~0x1];
	pfn1 = kvm->arch.guest_pmap[gfn | 0x1];

	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) |
		   (0x3 << ENTRYLO_C_SHIFT) | ENTRYLO_D | ENTRYLO_V;
	entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) |
		   (0x3 << ENTRYLO_C_SHIFT) | ENTRYLO_D | ENTRYLO_V;

	preempt_disable();
	entryhi = (vaddr | kvm_mips_get_kernel_asid(vcpu));
	ret = kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
				      flush_dcache_mask);
	preempt_enable();

	return ret;
}

int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu,
					 struct kvm_mips_tlb *tlb)
{
	unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
	struct kvm *kvm = vcpu->kvm;
	kvm_pfn_t pfn0, pfn1;
	int ret;

	if ((tlb->tlb_hi & VPN2_MASK) == 0) {
		pfn0 = 0;
		pfn1 = 0;
	} else {
		if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo[0])
					   >> PAGE_SHIFT) < 0)
			return -1;

		if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo[1])
					   >> PAGE_SHIFT) < 0)
			return -1;

		pfn0 = kvm->arch.guest_pmap[
			mips3_tlbpfn_to_paddr(tlb->tlb_lo[0]) >> PAGE_SHIFT];
		pfn1 = kvm->arch.guest_pmap[
			mips3_tlbpfn_to_paddr(tlb->tlb_lo[1]) >> PAGE_SHIFT];
	}

	/* Get attributes from the Guest TLB */
	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) |
		   (0x3 << ENTRYLO_C_SHIFT) |
		   (tlb->tlb_lo[0] & ENTRYLO_D) |
		   (tlb->tlb_lo[0] & ENTRYLO_V);
	entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) |
		   (0x3 << ENTRYLO_C_SHIFT) |
		   (tlb->tlb_lo[1] & ENTRYLO_D) |
		   (tlb->tlb_lo[1] & ENTRYLO_V);

	kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc,
		  tlb->tlb_lo[0], tlb->tlb_lo[1]);

	preempt_disable();
	entryhi = (tlb->tlb_hi & VPN2_MASK) | (KVM_GUEST_KERNEL_MODE(vcpu) ?
					       kvm_mips_get_kernel_asid(vcpu) :
					       kvm_mips_get_user_asid(vcpu));
	ret = kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
				      tlb->tlb_mask);
	preempt_enable();

	return ret;
}

void kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu,
			     struct kvm_vcpu *vcpu)
{
	unsigned long asid = asid_cache(cpu);

	asid += cpu_asid_inc();
	if (!(asid & cpu_asid_mask(&cpu_data[cpu]))) {
		if (cpu_has_vtag_icache)
			flush_icache_all();

		kvm_local_flush_tlb_all();      /* start new asid cycle */

		if (!asid)      /* fix version if needed */
			asid = asid_first_version(cpu);
	}

	cpu_context(cpu, mm) = asid_cache(cpu) = asid;
}

/**
 * kvm_mips_migrate_count() - Migrate timer.
 * @vcpu:	Virtual CPU.
 *
 * Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it
 * if it was running prior to being cancelled.
 *
 * Must be called when the VCPU is migrated to a different CPU to ensure that
 * timer expiry during guest execution interrupts the guest and causes the
 * interrupt to be delivered in a timely manner.
 */
static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu)
{
	if (hrtimer_cancel(&vcpu->arch.comparecount_timer))
		hrtimer_restart(&vcpu->arch.comparecount_timer);
}

/* Restore ASID once we are scheduled back after preemption */
void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
{
	unsigned long asid_mask = cpu_asid_mask(&cpu_data[cpu]);
	unsigned long flags;
	int newasid = 0;

	kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu);

	/* Allocate new kernel and user ASIDs if needed */

	local_irq_save(flags);

	if ((vcpu->arch.guest_kernel_asid[cpu] ^ asid_cache(cpu)) &
						asid_version_mask(cpu)) {
		kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu);
		vcpu->arch.guest_kernel_asid[cpu] =
		    vcpu->arch.guest_kernel_mm.context.asid[cpu];
		kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu, vcpu);
		vcpu->arch.guest_user_asid[cpu] =
		    vcpu->arch.guest_user_mm.context.asid[cpu];
		newasid++;

		kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
			  cpu_context(cpu, current->mm));
		kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
			  cpu, vcpu->arch.guest_kernel_asid[cpu]);
		kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
			  vcpu->arch.guest_user_asid[cpu]);
	}

	if (vcpu->arch.last_sched_cpu != cpu) {
		kvm_debug("[%d->%d]KVM VCPU[%d] switch\n",
			  vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id);
		/*
		 * Migrate the timer interrupt to the current CPU so that it
		 * always interrupts the guest and synchronously triggers a
		 * guest timer interrupt.
		 */
		kvm_mips_migrate_count(vcpu);
	}

	if (!newasid) {
		/*
		 * If we preempted while the guest was executing, then reload
		 * the pre-empted ASID
		 */
		if (current->flags & PF_VCPU) {
			write_c0_entryhi(vcpu->arch.
					 preempt_entryhi & asid_mask);
			ehb();
		}
	} else {
		/* New ASIDs were allocated for the VM */

		/*
		 * Were we in guest context? If so then the pre-empted ASID is
		 * no longer valid, we need to set it to what it should be based
		 * on the mode of the Guest (Kernel/User)
		 */
		if (current->flags & PF_VCPU) {
			if (KVM_GUEST_KERNEL_MODE(vcpu))
				write_c0_entryhi(vcpu->arch.
						 guest_kernel_asid[cpu] &
						 asid_mask);
			else
				write_c0_entryhi(vcpu->arch.
						 guest_user_asid[cpu] &
						 asid_mask);
			ehb();
		}
	}

	/* restore guest state to registers */
	kvm_mips_callbacks->vcpu_set_regs(vcpu);

	local_irq_restore(flags);

}

/* ASID can change if another task is scheduled during preemption */
void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
{
	unsigned long flags;
	int cpu;

	local_irq_save(flags);

	cpu = smp_processor_id();

	vcpu->arch.preempt_entryhi = read_c0_entryhi();
	vcpu->arch.last_sched_cpu = cpu;

	/* save guest state in registers */
	kvm_mips_callbacks->vcpu_get_regs(vcpu);

	if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) &
	     asid_version_mask(cpu))) {
		kvm_debug("%s: Dropping MMU Context:  %#lx\n", __func__,
			  cpu_context(cpu, current->mm));
		drop_mmu_context(current->mm, cpu);
	}
	write_c0_entryhi(cpu_asid(cpu, current->mm));
	ehb();

	local_irq_restore(flags);
}

u32 kvm_get_inst(u32 *opc, struct kvm_vcpu *vcpu)
{
	struct mips_coproc *cop0 = vcpu->arch.cop0;
	unsigned long paddr, flags, vpn2, asid;
	unsigned long va = (unsigned long)opc;
	u32 inst;
	int index;

	if (KVM_GUEST_KSEGX(va) < KVM_GUEST_KSEG0 ||
	    KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG23) {
		local_irq_save(flags);
		index = kvm_mips_host_tlb_lookup(vcpu, va);
		if (index >= 0) {
			inst = *(opc);
		} else {
			vpn2 = va & VPN2_MASK;
			asid = kvm_read_c0_guest_entryhi(cop0) &
						KVM_ENTRYHI_ASID;
			index = kvm_mips_guest_tlb_lookup(vcpu, vpn2 | asid);
			if (index < 0) {
				kvm_err("%s: get_user_failed for %p, vcpu: %p, ASID: %#lx\n",
					__func__, opc, vcpu, read_c0_entryhi());
				kvm_mips_dump_host_tlbs();
				local_irq_restore(flags);
				return KVM_INVALID_INST;
			}
			kvm_mips_handle_mapped_seg_tlb_fault(vcpu,
							     &vcpu->arch.
							     guest_tlb[index]);
			inst = *(opc);
		}
		local_irq_restore(flags);
	} else if (KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG0) {
		paddr = kvm_mips_translate_guest_kseg0_to_hpa(vcpu, va);
		inst = *(u32 *) CKSEG0ADDR(paddr);
	} else {
		kvm_err("%s: illegal address: %p\n", __func__, opc);
		return KVM_INVALID_INST;
	}

	return inst;
}
Commit	Line	Data
403015b3 JH	1	/*
	2	* This file is subject to the terms and conditions of the GNU General Public
	3	* License. See the file "COPYING" in the main directory of this archive
	4	* for more details.
	5	*
	6	* KVM/MIPS MMU handling in the KVM module.
	7	*
	8	* Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved.
	9	* Authors: Sanjay Lal <sanjayl@kymasys.com>
	10	*/
	11
	12	#include <linux/kvm_host.h>
	13	#include <asm/mmu_context.h>
	14
	15	static u32 kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu)
	16	{
	17	int cpu = smp_processor_id();
	18
	19	return vcpu->arch.guest_kernel_asid[cpu] &
	20	cpu_asid_mask(&cpu_data[cpu]);
	21	}
	22
	23	static u32 kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
	24	{
	25	int cpu = smp_processor_id();
	26
	27	return vcpu->arch.guest_user_asid[cpu] &
	28	cpu_asid_mask(&cpu_data[cpu]);
	29	}
	30
	31	static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
	32	{
	33	int srcu_idx, err = 0;
	34	kvm_pfn_t pfn;
	35
	36	if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE)
	37	return 0;
	38
	39	srcu_idx = srcu_read_lock(&kvm->srcu);
9befad23	40	pfn = gfn_to_pfn(kvm, gfn);
403015b3	41
9befad23	42	if (is_error_pfn(pfn)) {
403015b3 JH	43	kvm_err("Couldn't get pfn for gfn %#llx!\n", gfn);
	44	err = -EFAULT;
	45	goto out;
	46	}
	47
	48	kvm->arch.guest_pmap[gfn] = pfn;
	49	out:
	50	srcu_read_unlock(&kvm->srcu, srcu_idx);
	51	return err;
	52	}
	53
	54	/* Translate guest KSEG0 addresses to Host PA */
	55	unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu,
	56	unsigned long gva)
	57	{
	58	gfn_t gfn;
	59	unsigned long offset = gva & ~PAGE_MASK;
	60	struct kvm *kvm = vcpu->kvm;
	61
	62	if (KVM_GUEST_KSEGX(gva) != KVM_GUEST_KSEG0) {
	63	kvm_err("%s/%p: Invalid gva: %#lx\n", __func__,
	64	__builtin_return_address(0), gva);
	65	return KVM_INVALID_PAGE;
	66	}
	67
	68	gfn = (KVM_GUEST_CPHYSADDR(gva) >> PAGE_SHIFT);
	69
	70	if (gfn >= kvm->arch.guest_pmap_npages) {
	71	kvm_err("%s: Invalid gfn: %#llx, GVA: %#lx\n", __func__, gfn,
	72	gva);
	73	return KVM_INVALID_PAGE;
	74	}
	75
	76	if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
	77	return KVM_INVALID_ADDR;
	78
	79	return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset;
	80	}
	81
	82	/* XXXKYMA: Must be called with interrupts disabled */
	83	int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr,
	84	struct kvm_vcpu *vcpu)
	85	{
	86	gfn_t gfn;
	87	kvm_pfn_t pfn0, pfn1;
	88	unsigned long vaddr = 0;
	89	unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
403015b3 JH	90	struct kvm *kvm = vcpu->kvm;
	91	const int flush_dcache_mask = 0;
	92	int ret;
	93
	94	if (KVM_GUEST_KSEGX(badvaddr) != KVM_GUEST_KSEG0) {
	95	kvm_err("%s: Invalid BadVaddr: %#lx\n", __func__, badvaddr);
	96	kvm_mips_dump_host_tlbs();
	97	return -1;
	98	}
	99
	100	gfn = (KVM_GUEST_CPHYSADDR(badvaddr) >> PAGE_SHIFT);
	101	if (gfn >= kvm->arch.guest_pmap_npages) {
	102	kvm_err("%s: Invalid gfn: %#llx, BadVaddr: %#lx\n", __func__,
	103	gfn, badvaddr);
	104	kvm_mips_dump_host_tlbs();
	105	return -1;
	106	}
403015b3 JH	107	vaddr = badvaddr & (PAGE_MASK << 1);
	108
	109	if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
	110	return -1;
	111
	112	if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0)
	113	return -1;
	114
021df206 JH	115	pfn0 = kvm->arch.guest_pmap[gfn & ~0x1];
021df206 JH	116	pfn1 = kvm->arch.guest_pmap[gfn \| 0x1];
403015b3	117
e6207bbe JH	118	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) \|
	119	(0x3 << ENTRYLO_C_SHIFT) \| ENTRYLO_D \| ENTRYLO_V;
	120	entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) \|
	121	(0x3 << ENTRYLO_C_SHIFT) \| ENTRYLO_D \| ENTRYLO_V;
403015b3 JH	122
	123	preempt_disable();
	124	entryhi = (vaddr \| kvm_mips_get_kernel_asid(vcpu));
	125	ret = kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
	126	flush_dcache_mask);
	127	preempt_enable();
	128
	129	return ret;
	130	}
	131
	132	int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu,
26ee17ff	133	struct kvm_mips_tlb *tlb)
403015b3 JH	134	{
	135	unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
	136	struct kvm *kvm = vcpu->kvm;
	137	kvm_pfn_t pfn0, pfn1;
	138	int ret;
	139
	140	if ((tlb->tlb_hi & VPN2_MASK) == 0) {
	141	pfn0 = 0;
	142	pfn1 = 0;
	143	} else {
9fbfb06a	144	if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo[0])
403015b3 JH	145	>> PAGE_SHIFT) < 0)
	146	return -1;
	147
9fbfb06a	148	if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo[1])
403015b3 JH	149	>> PAGE_SHIFT) < 0)
	150	return -1;
	151
9fbfb06a JH	152	pfn0 = kvm->arch.guest_pmap[
	153	mips3_tlbpfn_to_paddr(tlb->tlb_lo[0]) >> PAGE_SHIFT];
	154	pfn1 = kvm->arch.guest_pmap[
	155	mips3_tlbpfn_to_paddr(tlb->tlb_lo[1]) >> PAGE_SHIFT];
403015b3 JH	156	}
403015b3 JH	157
403015b3	158	/* Get attributes from the Guest TLB */
e6207bbe JH	159	entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) \|
	160	(0x3 << ENTRYLO_C_SHIFT) \|
	161	(tlb->tlb_lo[0] & ENTRYLO_D) \|
	162	(tlb->tlb_lo[0] & ENTRYLO_V);
	163	entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) \|
	164	(0x3 << ENTRYLO_C_SHIFT) \|
	165	(tlb->tlb_lo[1] & ENTRYLO_D) \|
	166	(tlb->tlb_lo[1] & ENTRYLO_V);
403015b3 JH	167
403015b3 JH	168	kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc,
9fbfb06a	169	tlb->tlb_lo[0], tlb->tlb_lo[1]);
403015b3 JH	170
	171	preempt_disable();
	172	entryhi = (tlb->tlb_hi & VPN2_MASK) \| (KVM_GUEST_KERNEL_MODE(vcpu) ?
	173	kvm_mips_get_kernel_asid(vcpu) :
	174	kvm_mips_get_user_asid(vcpu));
	175	ret = kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
	176	tlb->tlb_mask);
	177	preempt_enable();
	178
	179	return ret;
	180	}
	181
	182	void kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu,
	183	struct kvm_vcpu *vcpu)
	184	{
	185	unsigned long asid = asid_cache(cpu);
	186
	187	asid += cpu_asid_inc();
	188	if (!(asid & cpu_asid_mask(&cpu_data[cpu]))) {
	189	if (cpu_has_vtag_icache)
	190	flush_icache_all();
	191
	192	kvm_local_flush_tlb_all(); /* start new asid cycle */
	193
	194	if (!asid) /* fix version if needed */
	195	asid = asid_first_version(cpu);
	196	}
	197
	198	cpu_context(cpu, mm) = asid_cache(cpu) = asid;
	199	}
	200
	201	/**
	202	* kvm_mips_migrate_count() - Migrate timer.
	203	* @vcpu: Virtual CPU.
	204	*
	205	* Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it
	206	* if it was running prior to being cancelled.
	207	*
	208	* Must be called when the VCPU is migrated to a different CPU to ensure that
	209	* timer expiry during guest execution interrupts the guest and causes the
	210	* interrupt to be delivered in a timely manner.
	211	*/
	212	static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu)
	213	{
	214	if (hrtimer_cancel(&vcpu->arch.comparecount_timer))
	215	hrtimer_restart(&vcpu->arch.comparecount_timer);
	216	}
	217
	218	/* Restore ASID once we are scheduled back after preemption */
	219	void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
	220	{
	221	unsigned long asid_mask = cpu_asid_mask(&cpu_data[cpu]);
	222	unsigned long flags;
	223	int newasid = 0;
	224
	225	kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu);
	226
	227	/* Allocate new kernel and user ASIDs if needed */
	228
	229	local_irq_save(flags);
	230
	231	if ((vcpu->arch.guest_kernel_asid[cpu] ^ asid_cache(cpu)) &
	232	asid_version_mask(cpu)) {
	233	kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu);
234	vcpu->arch.guest_kernel_asid[cpu] =
235	vcpu->arch.guest_kernel_mm.context.asid[cpu];
236	kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu, vcpu);
237	vcpu->arch.guest_user_asid[cpu] =
238	vcpu->arch.guest_user_mm.context.asid[cpu];
239	newasid++;
240
241	kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
242	cpu_context(cpu, current->mm));
243	kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
244	cpu, vcpu->arch.guest_kernel_asid[cpu]);
245	kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
246	vcpu->arch.guest_user_asid[cpu]);
247	}
248
249	if (vcpu->arch.last_sched_cpu != cpu) {
250	kvm_debug("[%d->%d]KVM VCPU[%d] switch\n",
251	vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id);
252	/*
253	* Migrate the timer interrupt to the current CPU so that it
254	* always interrupts the guest and synchronously triggers a
255	* guest timer interrupt.
256	*/
257	kvm_mips_migrate_count(vcpu);
258	}
259
260	if (!newasid) {
261	/*
262	* If we preempted while the guest was executing, then reload
263	* the pre-empted ASID
264	*/
265	if (current->flags & PF_VCPU) {
266	write_c0_entryhi(vcpu->arch.
267	preempt_entryhi & asid_mask);
268	ehb();
269	}
270	} else {
271	/* New ASIDs were allocated for the VM */
272
273	/*
274	* Were we in guest context? If so then the pre-empted ASID is
275	* no longer valid, we need to set it to what it should be based
276	* on the mode of the Guest (Kernel/User)
277	*/
278	if (current->flags & PF_VCPU) {
279	if (KVM_GUEST_KERNEL_MODE(vcpu))
280	write_c0_entryhi(vcpu->arch.
281	guest_kernel_asid[cpu] &
282	asid_mask);
283	else
284	write_c0_entryhi(vcpu->arch.
285	guest_user_asid[cpu] &
286	asid_mask);
287	ehb();
288	}
289	}
290
291	/* restore guest state to registers */
292	kvm_mips_callbacks->vcpu_set_regs(vcpu);
293
294	local_irq_restore(flags);
295
296	}
297
298	/* ASID can change if another task is scheduled during preemption */
299	void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
300	{
301	unsigned long flags;
302	int cpu;
303
304	local_irq_save(flags);
305
306	cpu = smp_processor_id();
307
308	vcpu->arch.preempt_entryhi = read_c0_entryhi();
309	vcpu->arch.last_sched_cpu = cpu;
310
311	/* save guest state in registers */
312	kvm_mips_callbacks->vcpu_get_regs(vcpu);
313
314	if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) &
315	asid_version_mask(cpu))) {
316	kvm_debug("%s: Dropping MMU Context: %#lx\n", __func__,
317	cpu_context(cpu, current->mm));
318	drop_mmu_context(current->mm, cpu);
319	}
320	write_c0_entryhi(cpu_asid(cpu, current->mm));
321	ehb();
322
323	local_irq_restore(flags);
324	}
325
326	u32 kvm_get_inst(u32 opc, struct kvm_vcpu vcpu)
327	{
328	struct mips_coproc *cop0 = vcpu->arch.cop0;
329	unsigned long paddr, flags, vpn2, asid;
35fec262	330	unsigned long va = (unsigned long)opc;
403015b3 JH	331	u32 inst;
	332	int index;
	333
35fec262 JH	334	if (KVM_GUEST_KSEGX(va) < KVM_GUEST_KSEG0 \|\|
35fec262 JH	335	KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG23) {
403015b3	336	local_irq_save(flags);
35fec262	337	index = kvm_mips_host_tlb_lookup(vcpu, va);
403015b3 JH	338	if (index >= 0) {
	339	inst = *(opc);
	340	} else {
35fec262	341	vpn2 = va & VPN2_MASK;
403015b3 JH	342	asid = kvm_read_c0_guest_entryhi(cop0) &
	343	KVM_ENTRYHI_ASID;
	344	index = kvm_mips_guest_tlb_lookup(vcpu, vpn2 \| asid);
	345	if (index < 0) {
	346	kvm_err("%s: get_user_failed for %p, vcpu: %p, ASID: %#lx\n",
	347	__func__, opc, vcpu, read_c0_entryhi());
	348	kvm_mips_dump_host_tlbs();
	349	local_irq_restore(flags);
	350	return KVM_INVALID_INST;
	351	}
	352	kvm_mips_handle_mapped_seg_tlb_fault(vcpu,
	353	&vcpu->arch.
26ee17ff	354	guest_tlb[index]);
403015b3 JH	355	inst = *(opc);
	356	}
	357	local_irq_restore(flags);
35fec262 JH	358	} else if (KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG0) {
35fec262 JH	359	paddr = kvm_mips_translate_guest_kseg0_to_hpa(vcpu, va);
403015b3 JH	360	inst = (u32 ) CKSEG0ADDR(paddr);
	361	} else {
	362	kvm_err("%s: illegal address: %p\n", __func__, opc);
	363	return KVM_INVALID_INST;
	364	}
	365
	366	return inst;
	367	}