blob: 57319ee57c4fdd1aada66e1648adc3981edf9dc3 [file] [log] [blame]
James Hogan403015b2016-06-09 14:19:10 +01001/*
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
James Hogan28cc5bd2016-07-08 11:53:22 +010012#include <linux/highmem.h>
James Hogan403015b2016-06-09 14:19:10 +010013#include <linux/kvm_host.h>
14#include <asm/mmu_context.h>
15
16static u32 kvm_mips_get_kernel_asid(struct kvm_vcpu *vcpu)
17{
18 int cpu = smp_processor_id();
19
20 return vcpu->arch.guest_kernel_asid[cpu] &
21 cpu_asid_mask(&cpu_data[cpu]);
22}
23
24static u32 kvm_mips_get_user_asid(struct kvm_vcpu *vcpu)
25{
26 int cpu = smp_processor_id();
27
28 return vcpu->arch.guest_user_asid[cpu] &
29 cpu_asid_mask(&cpu_data[cpu]);
30}
31
32static int kvm_mips_map_page(struct kvm *kvm, gfn_t gfn)
33{
34 int srcu_idx, err = 0;
35 kvm_pfn_t pfn;
36
37 if (kvm->arch.guest_pmap[gfn] != KVM_INVALID_PAGE)
38 return 0;
39
40 srcu_idx = srcu_read_lock(&kvm->srcu);
James Hogan9befad22016-06-09 14:19:11 +010041 pfn = gfn_to_pfn(kvm, gfn);
James Hogan403015b2016-06-09 14:19:10 +010042
James Hogan9befad22016-06-09 14:19:11 +010043 if (is_error_pfn(pfn)) {
James Hogan403015b2016-06-09 14:19:10 +010044 kvm_err("Couldn't get pfn for gfn %#llx!\n", gfn);
45 err = -EFAULT;
46 goto out;
47 }
48
49 kvm->arch.guest_pmap[gfn] = pfn;
50out:
51 srcu_read_unlock(&kvm->srcu, srcu_idx);
52 return err;
53}
54
55/* Translate guest KSEG0 addresses to Host PA */
56unsigned long kvm_mips_translate_guest_kseg0_to_hpa(struct kvm_vcpu *vcpu,
57 unsigned long gva)
58{
59 gfn_t gfn;
60 unsigned long offset = gva & ~PAGE_MASK;
61 struct kvm *kvm = vcpu->kvm;
62
63 if (KVM_GUEST_KSEGX(gva) != KVM_GUEST_KSEG0) {
64 kvm_err("%s/%p: Invalid gva: %#lx\n", __func__,
65 __builtin_return_address(0), gva);
66 return KVM_INVALID_PAGE;
67 }
68
69 gfn = (KVM_GUEST_CPHYSADDR(gva) >> PAGE_SHIFT);
70
71 if (gfn >= kvm->arch.guest_pmap_npages) {
72 kvm_err("%s: Invalid gfn: %#llx, GVA: %#lx\n", __func__, gfn,
73 gva);
74 return KVM_INVALID_PAGE;
75 }
76
77 if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
78 return KVM_INVALID_ADDR;
79
80 return (kvm->arch.guest_pmap[gfn] << PAGE_SHIFT) + offset;
81}
82
83/* XXXKYMA: Must be called with interrupts disabled */
84int kvm_mips_handle_kseg0_tlb_fault(unsigned long badvaddr,
85 struct kvm_vcpu *vcpu)
86{
87 gfn_t gfn;
88 kvm_pfn_t pfn0, pfn1;
89 unsigned long vaddr = 0;
90 unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
James Hogan403015b2016-06-09 14:19:10 +010091 struct kvm *kvm = vcpu->kvm;
92 const int flush_dcache_mask = 0;
93 int ret;
94
95 if (KVM_GUEST_KSEGX(badvaddr) != KVM_GUEST_KSEG0) {
96 kvm_err("%s: Invalid BadVaddr: %#lx\n", __func__, badvaddr);
97 kvm_mips_dump_host_tlbs();
98 return -1;
99 }
100
101 gfn = (KVM_GUEST_CPHYSADDR(badvaddr) >> PAGE_SHIFT);
102 if (gfn >= kvm->arch.guest_pmap_npages) {
103 kvm_err("%s: Invalid gfn: %#llx, BadVaddr: %#lx\n", __func__,
104 gfn, badvaddr);
105 kvm_mips_dump_host_tlbs();
106 return -1;
107 }
James Hogan403015b2016-06-09 14:19:10 +0100108 vaddr = badvaddr & (PAGE_MASK << 1);
109
110 if (kvm_mips_map_page(vcpu->kvm, gfn) < 0)
111 return -1;
112
113 if (kvm_mips_map_page(vcpu->kvm, gfn ^ 0x1) < 0)
114 return -1;
115
James Hogan021df202016-06-09 14:19:12 +0100116 pfn0 = kvm->arch.guest_pmap[gfn & ~0x1];
117 pfn1 = kvm->arch.guest_pmap[gfn | 0x1];
James Hogan403015b2016-06-09 14:19:10 +0100118
James Hogane6207bb2016-06-09 14:19:19 +0100119 entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) |
James Hogan7414d2f2016-06-15 19:29:58 +0100120 ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) |
121 ENTRYLO_D | ENTRYLO_V;
James Hogane6207bb2016-06-09 14:19:19 +0100122 entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) |
James Hogan7414d2f2016-06-15 19:29:58 +0100123 ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) |
124 ENTRYLO_D | ENTRYLO_V;
James Hogan403015b2016-06-09 14:19:10 +0100125
126 preempt_disable();
127 entryhi = (vaddr | kvm_mips_get_kernel_asid(vcpu));
128 ret = kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
129 flush_dcache_mask);
130 preempt_enable();
131
132 return ret;
133}
134
135int kvm_mips_handle_mapped_seg_tlb_fault(struct kvm_vcpu *vcpu,
James Hogan26ee17f2016-06-09 14:19:13 +0100136 struct kvm_mips_tlb *tlb)
James Hogan403015b2016-06-09 14:19:10 +0100137{
138 unsigned long entryhi = 0, entrylo0 = 0, entrylo1 = 0;
139 struct kvm *kvm = vcpu->kvm;
140 kvm_pfn_t pfn0, pfn1;
141 int ret;
142
143 if ((tlb->tlb_hi & VPN2_MASK) == 0) {
144 pfn0 = 0;
145 pfn1 = 0;
146 } else {
James Hogan9fbfb062016-06-09 14:19:17 +0100147 if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo[0])
James Hogan403015b2016-06-09 14:19:10 +0100148 >> PAGE_SHIFT) < 0)
149 return -1;
150
James Hogan9fbfb062016-06-09 14:19:17 +0100151 if (kvm_mips_map_page(kvm, mips3_tlbpfn_to_paddr(tlb->tlb_lo[1])
James Hogan403015b2016-06-09 14:19:10 +0100152 >> PAGE_SHIFT) < 0)
153 return -1;
154
James Hogan9fbfb062016-06-09 14:19:17 +0100155 pfn0 = kvm->arch.guest_pmap[
156 mips3_tlbpfn_to_paddr(tlb->tlb_lo[0]) >> PAGE_SHIFT];
157 pfn1 = kvm->arch.guest_pmap[
158 mips3_tlbpfn_to_paddr(tlb->tlb_lo[1]) >> PAGE_SHIFT];
James Hogan403015b2016-06-09 14:19:10 +0100159 }
160
James Hogan403015b2016-06-09 14:19:10 +0100161 /* Get attributes from the Guest TLB */
James Hogane6207bb2016-06-09 14:19:19 +0100162 entrylo0 = mips3_paddr_to_tlbpfn(pfn0 << PAGE_SHIFT) |
James Hogan7414d2f2016-06-15 19:29:58 +0100163 ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) |
164 (tlb->tlb_lo[0] & ENTRYLO_D) |
165 (tlb->tlb_lo[0] & ENTRYLO_V);
James Hogane6207bb2016-06-09 14:19:19 +0100166 entrylo1 = mips3_paddr_to_tlbpfn(pfn1 << PAGE_SHIFT) |
James Hogan7414d2f2016-06-15 19:29:58 +0100167 ((_page_cachable_default >> _CACHE_SHIFT) << ENTRYLO_C_SHIFT) |
168 (tlb->tlb_lo[1] & ENTRYLO_D) |
169 (tlb->tlb_lo[1] & ENTRYLO_V);
James Hogan403015b2016-06-09 14:19:10 +0100170
171 kvm_debug("@ %#lx tlb_lo0: 0x%08lx tlb_lo1: 0x%08lx\n", vcpu->arch.pc,
James Hogan9fbfb062016-06-09 14:19:17 +0100172 tlb->tlb_lo[0], tlb->tlb_lo[1]);
James Hogan403015b2016-06-09 14:19:10 +0100173
174 preempt_disable();
175 entryhi = (tlb->tlb_hi & VPN2_MASK) | (KVM_GUEST_KERNEL_MODE(vcpu) ?
176 kvm_mips_get_kernel_asid(vcpu) :
177 kvm_mips_get_user_asid(vcpu));
178 ret = kvm_mips_host_tlb_write(vcpu, entryhi, entrylo0, entrylo1,
179 tlb->tlb_mask);
180 preempt_enable();
181
182 return ret;
183}
184
185void kvm_get_new_mmu_context(struct mm_struct *mm, unsigned long cpu,
186 struct kvm_vcpu *vcpu)
187{
188 unsigned long asid = asid_cache(cpu);
189
190 asid += cpu_asid_inc();
191 if (!(asid & cpu_asid_mask(&cpu_data[cpu]))) {
192 if (cpu_has_vtag_icache)
193 flush_icache_all();
194
195 kvm_local_flush_tlb_all(); /* start new asid cycle */
196
197 if (!asid) /* fix version if needed */
198 asid = asid_first_version(cpu);
199 }
200
201 cpu_context(cpu, mm) = asid_cache(cpu) = asid;
202}
203
204/**
205 * kvm_mips_migrate_count() - Migrate timer.
206 * @vcpu: Virtual CPU.
207 *
208 * Migrate CP0_Count hrtimer to the current CPU by cancelling and restarting it
209 * if it was running prior to being cancelled.
210 *
211 * Must be called when the VCPU is migrated to a different CPU to ensure that
212 * timer expiry during guest execution interrupts the guest and causes the
213 * interrupt to be delivered in a timely manner.
214 */
215static void kvm_mips_migrate_count(struct kvm_vcpu *vcpu)
216{
217 if (hrtimer_cancel(&vcpu->arch.comparecount_timer))
218 hrtimer_restart(&vcpu->arch.comparecount_timer);
219}
220
221/* Restore ASID once we are scheduled back after preemption */
222void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
223{
224 unsigned long asid_mask = cpu_asid_mask(&cpu_data[cpu]);
225 unsigned long flags;
226 int newasid = 0;
227
228 kvm_debug("%s: vcpu %p, cpu: %d\n", __func__, vcpu, cpu);
229
230 /* Allocate new kernel and user ASIDs if needed */
231
232 local_irq_save(flags);
233
234 if ((vcpu->arch.guest_kernel_asid[cpu] ^ asid_cache(cpu)) &
235 asid_version_mask(cpu)) {
236 kvm_get_new_mmu_context(&vcpu->arch.guest_kernel_mm, cpu, vcpu);
237 vcpu->arch.guest_kernel_asid[cpu] =
238 vcpu->arch.guest_kernel_mm.context.asid[cpu];
239 kvm_get_new_mmu_context(&vcpu->arch.guest_user_mm, cpu, vcpu);
240 vcpu->arch.guest_user_asid[cpu] =
241 vcpu->arch.guest_user_mm.context.asid[cpu];
242 newasid++;
243
244 kvm_debug("[%d]: cpu_context: %#lx\n", cpu,
245 cpu_context(cpu, current->mm));
246 kvm_debug("[%d]: Allocated new ASID for Guest Kernel: %#x\n",
247 cpu, vcpu->arch.guest_kernel_asid[cpu]);
248 kvm_debug("[%d]: Allocated new ASID for Guest User: %#x\n", cpu,
249 vcpu->arch.guest_user_asid[cpu]);
250 }
251
252 if (vcpu->arch.last_sched_cpu != cpu) {
253 kvm_debug("[%d->%d]KVM VCPU[%d] switch\n",
254 vcpu->arch.last_sched_cpu, cpu, vcpu->vcpu_id);
255 /*
256 * Migrate the timer interrupt to the current CPU so that it
257 * always interrupts the guest and synchronously triggers a
258 * guest timer interrupt.
259 */
260 kvm_mips_migrate_count(vcpu);
261 }
262
263 if (!newasid) {
264 /*
265 * If we preempted while the guest was executing, then reload
266 * the pre-empted ASID
267 */
268 if (current->flags & PF_VCPU) {
269 write_c0_entryhi(vcpu->arch.
270 preempt_entryhi & asid_mask);
271 ehb();
272 }
273 } else {
274 /* New ASIDs were allocated for the VM */
275
276 /*
277 * Were we in guest context? If so then the pre-empted ASID is
278 * no longer valid, we need to set it to what it should be based
279 * on the mode of the Guest (Kernel/User)
280 */
281 if (current->flags & PF_VCPU) {
282 if (KVM_GUEST_KERNEL_MODE(vcpu))
283 write_c0_entryhi(vcpu->arch.
284 guest_kernel_asid[cpu] &
285 asid_mask);
286 else
287 write_c0_entryhi(vcpu->arch.
288 guest_user_asid[cpu] &
289 asid_mask);
290 ehb();
291 }
292 }
293
294 /* restore guest state to registers */
295 kvm_mips_callbacks->vcpu_set_regs(vcpu);
296
297 local_irq_restore(flags);
298
299}
300
301/* ASID can change if another task is scheduled during preemption */
302void kvm_arch_vcpu_put(struct kvm_vcpu *vcpu)
303{
304 unsigned long flags;
305 int cpu;
306
307 local_irq_save(flags);
308
309 cpu = smp_processor_id();
310
311 vcpu->arch.preempt_entryhi = read_c0_entryhi();
312 vcpu->arch.last_sched_cpu = cpu;
313
314 /* save guest state in registers */
315 kvm_mips_callbacks->vcpu_get_regs(vcpu);
316
317 if (((cpu_context(cpu, current->mm) ^ asid_cache(cpu)) &
318 asid_version_mask(cpu))) {
319 kvm_debug("%s: Dropping MMU Context: %#lx\n", __func__,
320 cpu_context(cpu, current->mm));
321 drop_mmu_context(current->mm, cpu);
322 }
323 write_c0_entryhi(cpu_asid(cpu, current->mm));
324 ehb();
325
326 local_irq_restore(flags);
327}
328
329u32 kvm_get_inst(u32 *opc, struct kvm_vcpu *vcpu)
330{
331 struct mips_coproc *cop0 = vcpu->arch.cop0;
332 unsigned long paddr, flags, vpn2, asid;
James Hogan35fec262016-06-09 14:19:21 +0100333 unsigned long va = (unsigned long)opc;
James Hogan28cc5bd2016-07-08 11:53:22 +0100334 void *vaddr;
James Hogan403015b2016-06-09 14:19:10 +0100335 u32 inst;
336 int index;
337
James Hogan35fec262016-06-09 14:19:21 +0100338 if (KVM_GUEST_KSEGX(va) < KVM_GUEST_KSEG0 ||
339 KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG23) {
James Hogan403015b2016-06-09 14:19:10 +0100340 local_irq_save(flags);
James Hogan35fec262016-06-09 14:19:21 +0100341 index = kvm_mips_host_tlb_lookup(vcpu, va);
James Hogan403015b2016-06-09 14:19:10 +0100342 if (index >= 0) {
343 inst = *(opc);
344 } else {
James Hogan35fec262016-06-09 14:19:21 +0100345 vpn2 = va & VPN2_MASK;
James Hogan403015b2016-06-09 14:19:10 +0100346 asid = kvm_read_c0_guest_entryhi(cop0) &
347 KVM_ENTRYHI_ASID;
348 index = kvm_mips_guest_tlb_lookup(vcpu, vpn2 | asid);
349 if (index < 0) {
350 kvm_err("%s: get_user_failed for %p, vcpu: %p, ASID: %#lx\n",
351 __func__, opc, vcpu, read_c0_entryhi());
352 kvm_mips_dump_host_tlbs();
James Hoganeafc4ed2016-06-14 09:40:16 +0100353 kvm_mips_dump_guest_tlbs(vcpu);
James Hogan403015b2016-06-09 14:19:10 +0100354 local_irq_restore(flags);
355 return KVM_INVALID_INST;
356 }
357 kvm_mips_handle_mapped_seg_tlb_fault(vcpu,
358 &vcpu->arch.
James Hogan26ee17f2016-06-09 14:19:13 +0100359 guest_tlb[index]);
James Hogan403015b2016-06-09 14:19:10 +0100360 inst = *(opc);
361 }
362 local_irq_restore(flags);
James Hogan35fec262016-06-09 14:19:21 +0100363 } else if (KVM_GUEST_KSEGX(va) == KVM_GUEST_KSEG0) {
364 paddr = kvm_mips_translate_guest_kseg0_to_hpa(vcpu, va);
James Hogan28cc5bd2016-07-08 11:53:22 +0100365 vaddr = kmap_atomic(pfn_to_page(PHYS_PFN(paddr)));
366 vaddr += paddr & ~PAGE_MASK;
367 inst = *(u32 *)vaddr;
368 kunmap_atomic(vaddr);
James Hogan403015b2016-06-09 14:19:10 +0100369 } else {
370 kvm_err("%s: illegal address: %p\n", __func__, opc);
371 return KVM_INVALID_INST;
372 }
373
374 return inst;
375}