diff options
Diffstat (limited to 'kernel/arch/mips/kvm/tlb.c')
-rw-r--r-- | kernel/arch/mips/kvm/tlb.c | 816 |
1 files changed, 816 insertions, 0 deletions
diff --git a/kernel/arch/mips/kvm/tlb.c b/kernel/arch/mips/kvm/tlb.c new file mode 100644 index 000000000..aed0ac2a4 --- /dev/null +++ b/kernel/arch/mips/kvm/tlb.c @@ -0,0 +1,816 @@ +/* + * 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 TLB handling, this file is part of the Linux host kernel so that + * TLB handlers run from KSEG0 + * + * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved. + * Authors: Sanjay Lal <sanjayl@kymasys.com> + */ + +#include <linux/sched.h> +#include <linux/smp.h> +#include <linux/mm.h> +#include <linux/delay.h> +#include <linux/module.h> +#include <linux/kvm_host.h> +#include <linux/srcu.h> + +#include <asm/cpu.h> +#include <asm/bootinfo.h> +#include <asm/mmu_context.h> +#include <asm/pgtable.h> +#include <asm/cacheflush.h> +#include <asm/tlb.h> + +#undef CONFIG_MIPS_MT +#include <asm/r4kcache.h> +#define CONFIG_MIPS_MT + +#define KVM_GUEST_PC_TLB 0 +#define KVM_GUEST_SP_TLB 1 + +#define PRIx64 "llx" + +atomic_t kvm_mips_instance; +EXPORT_SYMBOL(kvm_mips_instance); + +/* These function pointers are initialized once the KVM module is loaded */ +pfn_t (*kvm_mips_gfn_to_pfn)(struct kvm *kvm, gfn_t gfn); +EXPORT_SYMBOL(kvm_mips_gfn_to_pfn); + +void (*kvm_mips_release_pfn_clean)(pfn_t pfn); +EXPORT_SYMBOL(kvm_mips_release_pfn_clean); + +bool (*kvm_mips_is_error_pfn)(pfn_t pfn); +EXPORT_SYMBOL(kvm_mips_is_error_pfn); + +uint32_t kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.guest_kernel_asid[smp_processor_id()] & ASID_MASK; +} + +uint32_t kvm_mips_get_user_asid(struct kvm_vcpu *vcpu) +{ + return vcpu->arch.guest_user_asid[smp_processor_id()] & ASID_MASK; +} + +inline uint32_t kvm_mips_get_commpage_asid(struct kvm_vcpu *vcpu) +{ + return vcpu->kvm->arch.commpage_tlb; +} + +/* Structure defining an tlb entry data set. */ + +void kvm_mips_dump_host_tlbs(void) +{ + unsigned long old_entryhi; + unsigned long old_pagemask; + struct kvm_mips_tlb tlb; + unsigned long flags; + int i; + + local_irq_save(flags); + + old_entryhi = read_c0_entryhi(); + old_pagemask = read_c0_pagemask(); + + kvm_info("HOST TLBs:\n"); + kvm_info("ASID: %#lx\n", read_c0_entryhi() & ASID_MASK); + + for (i = 0; i < current_cpu_data.tlbsize; i++) { + write_c0_index(i); + mtc0_tlbw_hazard(); + + tlb_read(); + tlbw_use_hazard(); + + tlb.tlb_hi = read_c0_entryhi(); + tlb.tlb_lo0 = read_c0_entrylo0(); + tlb.tlb_lo1 = read_c0_entrylo1(); + tlb.tlb_mask = read_c0_pagemask(); + + kvm_info("TLB%c%3d Hi 0x%08lx ", + (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*', + i, tlb.tlb_hi); + kvm_info("Lo0=0x%09" PRIx64 " %c%c attr %lx ", + (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo0), + (tlb.tlb_lo0 & MIPS3_PG_D) ? 'D' : ' ', + (tlb.tlb_lo0 & MIPS3_PG_G) ? 'G' : ' ', + (tlb.tlb_lo0 >> 3) & 7); + kvm_info("Lo1=0x%09" PRIx64 " %c%c attr %lx sz=%lx\n", + (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo1), + (tlb.tlb_lo1 & MIPS3_PG_D) ? 'D' : ' ', + (tlb.tlb_lo1 & MIPS3_PG_G) ? 'G' : ' ', + (tlb.tlb_lo1 >> 3) & 7, tlb.tlb_mask); + } + write_c0_entryhi(old_entryhi); + write_c0_pagemask(old_pagemask); + mtc0_tlbw_hazard(); + local_irq_restore(flags); +} +EXPORT_SYMBOL(kvm_mips_dump_host_tlbs); + +void kvm_mips_dump_guest_tlbs(struct kvm_vcpu *vcpu) +{ + struct mips_coproc *cop0 = vcpu->arch.cop0; + struct kvm_mips_tlb tlb; + int i; + + kvm_info("Guest TLBs:\n"); + kvm_info("Guest EntryHi: %#lx\n", kvm_read_c0_guest_entryhi(cop0)); + + for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) { + tlb = vcpu->arch.guest_tlb[i]; + kvm_info("TLB%c%3d Hi 0x%08lx ", + (tlb.tlb_lo0 | tlb.tlb_lo1) & MIPS3_PG_V ? ' ' : '*', + i, tlb.tlb_hi); + kvm_info("Lo0=0x%09" PRIx64 " %c%c attr %lx ", + (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo0), + (tlb.tlb_lo0 & MIPS3_PG_D) ? 'D' : ' ', + (tlb.tlb_lo0 & MIPS3_PG_G) ? 'G' : ' ', + (tlb.tlb_lo0 >> 3) & 7); + kvm_info("Lo1=0x%09" PRIx64 " %c%c attr %lx sz=%lx\n", + (uint64_t) mips3_tlbpfn_to_paddr(tlb.tlb_lo1), + (tlb.tlb_lo1 & MIPS3_PG_D) ? 'D' : ' ', + (tlb.tlb_lo1 & MIPS3_PG_G) ? 'G' : ' ', + (tlb.tlb_lo1 >> 3) & 7, tlb.tlb_mask); + } +} +EXPORT_SYMBOL(kvm_mips_dump_guest_tlbs); + +static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn) +{ + int srcu_idx, err = 0; + pfn_t pfn; + + if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE) + return 0; + + srcu_idx = srcu_read_lock(&kvm->srcu); + pfn = kvm_mips_gfn_to_pfn(kvm, gfn); + + if (kvm_mips_is_error_pfn(pfn)) { + kvm_err("Couldn't get pfn for gfn %#" PRIx64 "!\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; + uint32_t 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; +} +EXPORT_SYMBOL(kvm_mips_translate_guest_kseg0_to_hpa); + +/* XXXKYMA: Must be called with interrupts disabled */ +/* set flush_dcache_mask == 0 if no dcache flush required */ +int kvm_mips_host_tlb_write(struct kvm_vcpu *vcpu, unsigned long entryhi, + unsigned long entrylo0, unsigned long entrylo1, + int flush_dcache_mask) +{ + unsigned long flags; + unsigned long old_entryhi; + int idx; + + local_irq_save(flags); + + old_entryhi = read_c0_entryhi(); + write_c0_entryhi(entryhi); + mtc0_tlbw_hazard(); + + tlb_probe(); + tlb_probe_hazard(); + idx = read_c0_index(); + + if (idx > current_cpu_data.tlbsize) { + kvm_err("%s: Invalid Index: %d\n", __func__, idx); + kvm_mips_dump_host_tlbs(); + local_irq_restore(flags); + return -1; + } + + write_c0_entrylo0(entrylo0); + write_c0_entrylo1(entrylo1); + mtc0_tlbw_hazard(); + + if (idx < 0) + tlb_write_random(); + else + tlb_write_indexed(); + tlbw_use_hazard(); + + kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0(R): 0x%08lx, entrylo1(R): 0x%08lx\n", + vcpu->arch.pc, idx, read_c0_entryhi(), + read_c0_entrylo0(), read_c0_entrylo1()); + + /* Flush D-cache */ + if (flush_dcache_mask) { + if (entrylo0 & MIPS3_PG_V) { + ++vcpu->stat.flush_dcache_exits; + flush_data_cache_page((entryhi & VPN2_MASK) & + ~flush_dcache_mask); + } + if (entrylo1 & MIPS3_PG_V) { + ++vcpu->stat.flush_dcache_exits; + flush_data_cache_page(((entryhi & VPN2_MASK) & + ~flush_dcache_mask) | + (0x1 << PAGE_SHIFT)); + } + } + + /* Restore old ASID */ + write_c0_entryhi(old_entryhi); + mtc0_tlbw_hazard(); + tlbw_use_hazard(); + local_irq_restore(flags); + return 0; +} + +/* XXXKYMA: Must be called with interrupts disabled */ +int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr, + struct kvm_vcpu *vcpu) +{ + gfn_t gfn; + pfn_t pfn0, pfn1; + unsigned long vaddr = 0; + unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0; + int even; + struct kvm *kvm = vcpu->kvm; + const int flush_dcache_mask = 0; + + 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; + } + even = !(gfn & 0x1); + 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; + + if (even) { + pfn0 = kvm->arch.guest_pmap[gfn]; + pfn1 = kvm->arch.guest_pmap[gfn ^ 0x1]; + } else { + pfn0 = kvm->arch.guest_pmap[gfn ^ 0x1]; + pfn1 = kvm->arch.guest_pmap[gfn]; + } + + entryhi = (vaddr | kvm_mips_get_kernel_asid(vcpu)); + entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) | + (1 << 2) | (0x1 << 1); + entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) | (0x3 << 3) | + (1 << 2) | (0x1 << 1); + + return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1, + flush_dcache_mask); +} +EXPORT_SYMBOL(kvm_mips_handle_kseg0_tlb_fault); + +int kvm_mips_handle_commpage_tlb_fault(unsigned long badvaddr, + struct kvm_vcpu *vcpu) +{ + pfn_t pfn0, pfn1; + unsigned long flags, old_entryhi = 0, vaddr = 0; + unsigned long entrylo0 = 0, entrylo1 = 0; + + pfn0 = CPHYSADDR(vcpu->arch.kseg0_commpage) >> PAGE_SHIFT; + pfn1 = 0; + entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) | + (1 << 2) | (0x1 << 1); + entrylo1 = 0; + + local_irq_save(flags); + + old_entryhi = read_c0_entryhi(); + vaddr = badvaddr & (PAGE_MASK << 1); + write_c0_entryhi(vaddr | kvm_mips_get_kernel_asid(vcpu)); + mtc0_tlbw_hazard(); + write_c0_entrylo0(entrylo0); + mtc0_tlbw_hazard(); + write_c0_entrylo1(entrylo1); + mtc0_tlbw_hazard(); + write_c0_index(kvm_mips_get_commpage_asid(vcpu)); + mtc0_tlbw_hazard(); + tlb_write_indexed(); + mtc0_tlbw_hazard(); + tlbw_use_hazard(); + + kvm_debug("@ %#lx idx: %2d [entryhi(R): %#lx] entrylo0 (R): 0x%08lx, entrylo1(R): 0x%08lx\n", + vcpu->arch.pc, read_c0_index(), read_c0_entryhi(), + read_c0_entrylo0(), read_c0_entrylo1()); + + /* Restore old ASID */ + write_c0_entryhi(old_entryhi); + mtc0_tlbw_hazard(); + tlbw_use_hazard(); + local_irq_restore(flags); + + return 0; +} +EXPORT_SYMBOL(kvm_mips_handle_commpage_tlb_fault); + +int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu, + struct kvm_mips_tlb *tlb, + unsigned long *hpa0, + unsigned long *hpa1) +{ + unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0; + struct kvm *kvm = vcpu->kvm; + pfn_t pfn0, pfn1; + + if ((tlb->tlb_hi & VPN2_MASK) == 0) { + pfn0 = 0; + pfn1 = 0; + } else { + if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo0) + >> PAGE_SHIFT) < 0) + return -1; + + if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo1) + >> PAGE_SHIFT) < 0) + return -1; + + pfn0 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo0) + >> PAGE_SHIFT]; + pfn1 = kvm->arch.guest_pmap[mips3_tlbpfn_to_paddr(tlb->tlb_lo1) + >> PAGE_SHIFT]; + } + + if (hpa0) + *hpa0 = pfn0 << PAGE_SHIFT; + + if (hpa1) + *hpa1 = pfn1 << PAGE_SHIFT; + + /* Get attributes from the Guest TLB */ + entryhi = (tlb->tlb_hi & VPN2_MASK) | (KVM_GUEST_KERNEL_MODE(vcpu) ? + kvm_mips_get_kernel_asid(vcpu) : + kvm_mips_get_user_asid(vcpu)); + entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) | (0x3 << 3) | + (tlb->tlb_lo0 & MIPS3_PG_D) | (tlb->tlb_lo0 & MIPS3_PG_V); + entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) | (0x3 << 3) | + (tlb->tlb_lo1 & MIPS3_PG_D) | (tlb->tlb_lo1 & MIPS3_PG_V); + + kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc, + tlb->tlb_lo0, tlb->tlb_lo1); + + return kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1, + tlb->tlb_mask); +} +EXPORT_SYMBOL(kvm_mips_handle_mapped_seg_tlb_fault); + +int kvm_mips_guest_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long entryhi) +{ + int i; + int index = -1; + struct kvm_mips_tlb *tlb = vcpu->arch.guest_tlb; + + for (i = 0; i < KVM_MIPS_GUEST_TLB_SIZE; i++) { + if (TLB_HI_VPN2_HIT(tlb[i], entryhi) && + TLB_HI_ASID_HIT(tlb[i], entryhi)) { + index = i; + break; + } + } + + kvm_debug("%s: entryhi: %#lx, index: %d lo0: %#lx, lo1: %#lx\n", + __func__, entryhi, index, tlb[i].tlb_lo0, tlb[i].tlb_lo1); + + return index; +} +EXPORT_SYMBOL(kvm_mips_guest_tlb_lookup); + +int kvm_mips_host_tlb_lookup(struct kvm_vcpu *vcpu, unsigned long vaddr) +{ + unsigned long old_entryhi, flags; + int idx; + + local_irq_save(flags); + + old_entryhi = read_c0_entryhi(); + + if (KVM_GUEST_KERNEL_MODE(vcpu)) + write_c0_entryhi((vaddr & VPN2_MASK) | + kvm_mips_get_kernel_asid(vcpu)); + else { + write_c0_entryhi((vaddr & VPN2_MASK) | + kvm_mips_get_user_asid(vcpu)); + } + + mtc0_tlbw_hazard(); + + tlb_probe(); + tlb_probe_hazard(); + idx = read_c0_index(); + + /* Restore old ASID */ + write_c0_entryhi(old_entryhi); + mtc0_tlbw_hazard(); + tlbw_use_hazard(); + + local_irq_restore(flags); + + kvm_debug("Host TLB lookup, %#lx, idx: %2d\n", vaddr, idx); + + return idx; +} +EXPORT_SYMBOL(kvm_mips_host_tlb_lookup); + +int kvm_mips_host_tlb_inv(struct kvm_vcpu *vcpu, unsigned long va) +{ + int idx; + unsigned long flags, old_entryhi; + + local_irq_save(flags); + + old_entryhi = read_c0_entryhi(); + + write_c0_entryhi((va & VPN2_MASK) | kvm_mips_get_user_asid(vcpu)); + mtc0_tlbw_hazard(); + + tlb_probe(); + tlb_probe_hazard(); + idx = read_c0_index(); + + if (idx >= current_cpu_data.tlbsize) + BUG(); + + if (idx > 0) { + write_c0_entryhi(UNIQUE_ENTRYHI(idx)); + mtc0_tlbw_hazard(); + + write_c0_entrylo0(0); + mtc0_tlbw_hazard(); + + write_c0_entrylo1(0); + mtc0_tlbw_hazard(); + + tlb_write_indexed(); + mtc0_tlbw_hazard(); + } + + write_c0_entryhi(old_entryhi); + mtc0_tlbw_hazard(); + tlbw_use_hazard(); + + local_irq_restore(flags); + + if (idx > 0) + kvm_debug("%s: Invalidated entryhi %#lx @ idx %d\n", __func__, + (va & VPN2_MASK) | kvm_mips_get_user_asid(vcpu), idx); + + return 0; +} +EXPORT_SYMBOL(kvm_mips_host_tlb_inv); + +/* XXXKYMA: Fix Guest USER/KERNEL no longer share the same ASID */ +int kvm_mips_host_tlb_inv_index(struct kvm_vcpu *vcpu, int index) +{ + unsigned long flags, old_entryhi; + + if (index >= current_cpu_data.tlbsize) + BUG(); + + local_irq_save(flags); + + old_entryhi = read_c0_entryhi(); + + write_c0_entryhi(UNIQUE_ENTRYHI(index)); + mtc0_tlbw_hazard(); + + write_c0_index(index); + mtc0_tlbw_hazard(); + + write_c0_entrylo0(0); + mtc0_tlbw_hazard(); + + write_c0_entrylo1(0); + mtc0_tlbw_hazard(); + + tlb_write_indexed(); + mtc0_tlbw_hazard(); + tlbw_use_hazard(); + + write_c0_entryhi(old_entryhi); + mtc0_tlbw_hazard(); + tlbw_use_hazard(); + + local_irq_restore(flags); + + return 0; +} + +void kvm_mips_flush_host_tlb(int skip_kseg0) +{ + unsigned long flags; + unsigned long old_entryhi, entryhi; + unsigned long old_pagemask; + int entry = 0; + int maxentry = current_cpu_data.tlbsize; + + local_irq_save(flags); + + old_entryhi = read_c0_entryhi(); + old_pagemask = read_c0_pagemask(); + + /* Blast 'em all away. */ + for (entry = 0; entry < maxentry; entry++) { + write_c0_index(entry); + mtc0_tlbw_hazard(); + + if (skip_kseg0) { + tlb_read(); + tlbw_use_hazard(); + + entryhi = read_c0_entryhi(); + + /* Don't blow away guest kernel entries */ + if (KVM_GUEST_KSEGX(entryhi) == KVM_GUEST_KSEG0) + continue; + } + + /* Make sure all entries differ. */ + write_c0_entryhi(UNIQUE_ENTRYHI(entry)); + mtc0_tlbw_hazard(); + write_c0_entrylo0(0); + mtc0_tlbw_hazard(); + write_c0_entrylo1(0); + mtc0_tlbw_hazard(); + + tlb_write_indexed(); + mtc0_tlbw_hazard(); + } + + tlbw_use_hazard(); + + write_c0_entryhi(old_entryhi); + write_c0_pagemask(old_pagemask); + mtc0_tlbw_hazard(); + tlbw_use_hazard(); + + local_irq_restore(flags); +} +EXPORT_SYMBOL(kvm_mips_flush_host_tlb); + +void kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu, + struct kvm_vcpu *vcpu) +{ + unsigned long asid = asid_cache(cpu); + + asid += ASID_INC; + if (!(asid & ASID_MASK)) { + 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_context(cpu, mm) = asid_cache(cpu) = asid; +} + +void kvm_local_flush_tlb_all(void) +{ + unsigned long flags; + unsigned long old_ctx; + int entry = 0; + + local_irq_save(flags); + /* Save old context and create impossible VPN2 value */ + old_ctx = read_c0_entryhi(); + write_c0_entrylo0(0); + write_c0_entrylo1(0); + + /* Blast 'em all away. */ + while (entry < current_cpu_data.tlbsize) { + /* Make sure all entries differ. */ + write_c0_entryhi(UNIQUE_ENTRYHI(entry)); + write_c0_index(entry); + mtc0_tlbw_hazard(); + tlb_write_indexed(); + entry++; + } + tlbw_use_hazard(); + write_c0_entryhi(old_ctx); + mtc0_tlbw_hazard(); + + local_irq_restore(flags); +} +EXPORT_SYMBOL(kvm_local_flush_tlb_all); + +/** + * 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 flags; + int newasid = 0; + + kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu); + + /* Alocate new kernel and user ASIDs if needed */ + + local_irq_save(flags); + + if (((vcpu->arch. + guest_kernel_asid[cpu] ^ asid_cache(cpu)) & ASID_VERSION_MASK)) { + 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); + +} +EXPORT_SYMBOL(kvm_arch_vcpu_load); + +/* ASID can change if another task is scheduled during preemption */ +void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu) +{ + unsigned long flags; + uint32_t 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)) { + 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); +} +EXPORT_SYMBOL(kvm_arch_vcpu_put); + +uint32_t kvm_get_inst(uint32_t *opc, struct kvm_vcpu *vcpu) +{ + struct mips_coproc *cop0 = vcpu->arch.cop0; + unsigned long paddr, flags, vpn2, asid; + uint32_t inst; + int index; + + if (KVM_GUEST_KSEGX((unsigned long) opc) < KVM_GUEST_KSEG0 || + KVM_GUEST_KSEGX((unsigned long) opc) == KVM_GUEST_KSEG23) { + local_irq_save(flags); + index = kvm_mips_host_tlb_lookup(vcpu, (unsigned long) opc); + if (index >= 0) { + inst = *(opc); + } else { + vpn2 = (unsigned long) opc & VPN2_MASK; + asid = kvm_read_c0_guest_entryhi(cop0) & ASID_MASK; + 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], + NULL, NULL); + inst = *(opc); + } + local_irq_restore(flags); + } else if (KVM_GUEST_KSEGX(opc) == KVM_GUEST_KSEG0) { + paddr = + kvm_mips_translate_guest_kseg0_to_hpa(vcpu, + (unsigned long) opc); + inst = *(uint32_t *) CKSEG0ADDR(paddr); + } else { + kvm_err("%s: illegal address: %p\n", __func__, opc); + return KVM_INVALID_INST; + } + + return inst; +} +EXPORT_SYMBOL(kvm_get_inst); |