blob: 6984342da13d09fd0194563f4b598cfb913ec6c1 [file] [log] [blame]
Christoffer Dall749cf76c2013-01-20 18:28:06 -05001/*
2 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
3 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
4 *
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License, version 2, as
7 * published by the Free Software Foundation.
8 *
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
13 *
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
17 */
Christoffer Dall342cd0a2013-01-20 18:28:06 -050018
19#include <linux/mman.h>
20#include <linux/kvm_host.h>
21#include <linux/io.h>
Christoffer Dallad361f02012-11-01 17:14:45 +010022#include <linux/hugetlb.h>
Christoffer Dall45e96ea2013-01-20 18:43:58 -050023#include <trace/events/kvm.h>
Christoffer Dall342cd0a2013-01-20 18:28:06 -050024#include <asm/pgalloc.h>
Christoffer Dall94f8e642013-01-20 18:28:12 -050025#include <asm/cacheflush.h>
Christoffer Dall342cd0a2013-01-20 18:28:06 -050026#include <asm/kvm_arm.h>
27#include <asm/kvm_mmu.h>
Christoffer Dall45e96ea2013-01-20 18:43:58 -050028#include <asm/kvm_mmio.h>
Christoffer Dalld5d81842013-01-20 18:28:07 -050029#include <asm/kvm_asm.h>
Christoffer Dall94f8e642013-01-20 18:28:12 -050030#include <asm/kvm_emulate.h>
Christoffer Dalld5d81842013-01-20 18:28:07 -050031
32#include "trace.h"
Christoffer Dall342cd0a2013-01-20 18:28:06 -050033
34extern char __hyp_idmap_text_start[], __hyp_idmap_text_end[];
35
Marc Zyngier5a677ce2013-04-12 19:12:06 +010036static pgd_t *boot_hyp_pgd;
Marc Zyngier2fb41052013-04-12 19:12:03 +010037static pgd_t *hyp_pgd;
Ard Biesheuvele4c5a682015-03-19 16:42:28 +000038static pgd_t *merged_hyp_pgd;
Christoffer Dall342cd0a2013-01-20 18:28:06 -050039static DEFINE_MUTEX(kvm_hyp_pgd_mutex);
40
Marc Zyngier5a677ce2013-04-12 19:12:06 +010041static unsigned long hyp_idmap_start;
42static unsigned long hyp_idmap_end;
43static phys_addr_t hyp_idmap_vector;
44
Christoffer Dall38f791a2014-10-10 12:14:28 +020045#define hyp_pgd_order get_order(PTRS_PER_PGD * sizeof(pgd_t))
Mark Salter5d4e08c2014-03-28 14:25:19 +000046
Christoffer Dall9b5fdb92013-10-02 15:32:01 -070047#define kvm_pmd_huge(_x) (pmd_huge(_x) || pmd_trans_huge(_x))
Mario Smarduchc6473552015-01-15 15:58:56 -080048#define kvm_pud_huge(_x) pud_huge(_x)
Christoffer Dallad361f02012-11-01 17:14:45 +010049
Mario Smarduch15a49a42015-01-15 15:58:58 -080050#define KVM_S2PTE_FLAG_IS_IOMAP (1UL << 0)
51#define KVM_S2_FLAG_LOGGING_ACTIVE (1UL << 1)
52
53static bool memslot_is_logging(struct kvm_memory_slot *memslot)
54{
Mario Smarduch15a49a42015-01-15 15:58:58 -080055 return memslot->dirty_bitmap && !(memslot->flags & KVM_MEM_READONLY);
Mario Smarduch72760302015-01-15 15:59:01 -080056}
57
58/**
59 * kvm_flush_remote_tlbs() - flush all VM TLB entries for v7/8
60 * @kvm: pointer to kvm structure.
61 *
62 * Interface to HYP function to flush all VM TLB entries
63 */
64void kvm_flush_remote_tlbs(struct kvm *kvm)
65{
66 kvm_call_hyp(__kvm_tlb_flush_vmid, kvm);
Mario Smarduch15a49a42015-01-15 15:58:58 -080067}
Christoffer Dall342cd0a2013-01-20 18:28:06 -050068
Marc Zyngier48762762013-01-28 15:27:00 +000069static void kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
Christoffer Dalld5d81842013-01-20 18:28:07 -050070{
Marc Zyngierd4cb9df52013-05-14 12:11:34 +010071 /*
72 * This function also gets called when dealing with HYP page
73 * tables. As HYP doesn't have an associated struct kvm (and
74 * the HYP page tables are fairly static), we don't do
75 * anything there.
76 */
77 if (kvm)
78 kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, kvm, ipa);
Christoffer Dalld5d81842013-01-20 18:28:07 -050079}
80
Marc Zyngier363ef892014-12-19 16:48:06 +000081/*
82 * D-Cache management functions. They take the page table entries by
83 * value, as they are flushing the cache using the kernel mapping (or
84 * kmap on 32bit).
85 */
86static void kvm_flush_dcache_pte(pte_t pte)
87{
88 __kvm_flush_dcache_pte(pte);
89}
90
91static void kvm_flush_dcache_pmd(pmd_t pmd)
92{
93 __kvm_flush_dcache_pmd(pmd);
94}
95
96static void kvm_flush_dcache_pud(pud_t pud)
97{
98 __kvm_flush_dcache_pud(pud);
99}
100
Mario Smarduch15a49a42015-01-15 15:58:58 -0800101/**
102 * stage2_dissolve_pmd() - clear and flush huge PMD entry
103 * @kvm: pointer to kvm structure.
104 * @addr: IPA
105 * @pmd: pmd pointer for IPA
106 *
107 * Function clears a PMD entry, flushes addr 1st and 2nd stage TLBs. Marks all
108 * pages in the range dirty.
109 */
110static void stage2_dissolve_pmd(struct kvm *kvm, phys_addr_t addr, pmd_t *pmd)
111{
112 if (!kvm_pmd_huge(*pmd))
113 return;
114
115 pmd_clear(pmd);
116 kvm_tlb_flush_vmid_ipa(kvm, addr);
117 put_page(virt_to_page(pmd));
118}
119
Christoffer Dalld5d81842013-01-20 18:28:07 -0500120static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
121 int min, int max)
122{
123 void *page;
124
125 BUG_ON(max > KVM_NR_MEM_OBJS);
126 if (cache->nobjs >= min)
127 return 0;
128 while (cache->nobjs < max) {
129 page = (void *)__get_free_page(PGALLOC_GFP);
130 if (!page)
131 return -ENOMEM;
132 cache->objects[cache->nobjs++] = page;
133 }
134 return 0;
135}
136
137static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
138{
139 while (mc->nobjs)
140 free_page((unsigned long)mc->objects[--mc->nobjs]);
141}
142
143static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)
144{
145 void *p;
146
147 BUG_ON(!mc || !mc->nobjs);
148 p = mc->objects[--mc->nobjs];
149 return p;
150}
151
Christoffer Dall4f853a72014-05-09 23:31:31 +0200152static void clear_pgd_entry(struct kvm *kvm, pgd_t *pgd, phys_addr_t addr)
Marc Zyngier979acd52013-08-06 13:05:48 +0100153{
Christoffer Dall4f853a72014-05-09 23:31:31 +0200154 pud_t *pud_table __maybe_unused = pud_offset(pgd, 0);
155 pgd_clear(pgd);
156 kvm_tlb_flush_vmid_ipa(kvm, addr);
157 pud_free(NULL, pud_table);
158 put_page(virt_to_page(pgd));
Marc Zyngier979acd52013-08-06 13:05:48 +0100159}
160
Marc Zyngierd4cb9df52013-05-14 12:11:34 +0100161static void clear_pud_entry(struct kvm *kvm, pud_t *pud, phys_addr_t addr)
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500162{
Christoffer Dall4f853a72014-05-09 23:31:31 +0200163 pmd_t *pmd_table = pmd_offset(pud, 0);
164 VM_BUG_ON(pud_huge(*pud));
165 pud_clear(pud);
166 kvm_tlb_flush_vmid_ipa(kvm, addr);
167 pmd_free(NULL, pmd_table);
Marc Zyngier4f728272013-04-12 19:12:05 +0100168 put_page(virt_to_page(pud));
169}
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500170
Marc Zyngierd4cb9df52013-05-14 12:11:34 +0100171static void clear_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr)
Marc Zyngier4f728272013-04-12 19:12:05 +0100172{
Christoffer Dall4f853a72014-05-09 23:31:31 +0200173 pte_t *pte_table = pte_offset_kernel(pmd, 0);
174 VM_BUG_ON(kvm_pmd_huge(*pmd));
175 pmd_clear(pmd);
176 kvm_tlb_flush_vmid_ipa(kvm, addr);
177 pte_free_kernel(NULL, pte_table);
Marc Zyngier4f728272013-04-12 19:12:05 +0100178 put_page(virt_to_page(pmd));
179}
180
Marc Zyngier363ef892014-12-19 16:48:06 +0000181/*
182 * Unmapping vs dcache management:
183 *
184 * If a guest maps certain memory pages as uncached, all writes will
185 * bypass the data cache and go directly to RAM. However, the CPUs
186 * can still speculate reads (not writes) and fill cache lines with
187 * data.
188 *
189 * Those cache lines will be *clean* cache lines though, so a
190 * clean+invalidate operation is equivalent to an invalidate
191 * operation, because no cache lines are marked dirty.
192 *
193 * Those clean cache lines could be filled prior to an uncached write
194 * by the guest, and the cache coherent IO subsystem would therefore
195 * end up writing old data to disk.
196 *
197 * This is why right after unmapping a page/section and invalidating
198 * the corresponding TLBs, we call kvm_flush_dcache_p*() to make sure
199 * the IO subsystem will never hit in the cache.
200 */
Christoffer Dall4f853a72014-05-09 23:31:31 +0200201static void unmap_ptes(struct kvm *kvm, pmd_t *pmd,
202 phys_addr_t addr, phys_addr_t end)
Marc Zyngier4f728272013-04-12 19:12:05 +0100203{
Christoffer Dall4f853a72014-05-09 23:31:31 +0200204 phys_addr_t start_addr = addr;
205 pte_t *pte, *start_pte;
206
207 start_pte = pte = pte_offset_kernel(pmd, addr);
208 do {
209 if (!pte_none(*pte)) {
Marc Zyngier363ef892014-12-19 16:48:06 +0000210 pte_t old_pte = *pte;
211
Christoffer Dall4f853a72014-05-09 23:31:31 +0200212 kvm_set_pte(pte, __pte(0));
Christoffer Dall4f853a72014-05-09 23:31:31 +0200213 kvm_tlb_flush_vmid_ipa(kvm, addr);
Marc Zyngier363ef892014-12-19 16:48:06 +0000214
215 /* No need to invalidate the cache for device mappings */
216 if ((pte_val(old_pte) & PAGE_S2_DEVICE) != PAGE_S2_DEVICE)
217 kvm_flush_dcache_pte(old_pte);
218
219 put_page(virt_to_page(pte));
Christoffer Dall4f853a72014-05-09 23:31:31 +0200220 }
221 } while (pte++, addr += PAGE_SIZE, addr != end);
222
Christoffer Dall38f791a2014-10-10 12:14:28 +0200223 if (kvm_pte_table_empty(kvm, start_pte))
Christoffer Dall4f853a72014-05-09 23:31:31 +0200224 clear_pmd_entry(kvm, pmd, start_addr);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500225}
226
Christoffer Dall4f853a72014-05-09 23:31:31 +0200227static void unmap_pmds(struct kvm *kvm, pud_t *pud,
228 phys_addr_t addr, phys_addr_t end)
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500229{
Christoffer Dall4f853a72014-05-09 23:31:31 +0200230 phys_addr_t next, start_addr = addr;
231 pmd_t *pmd, *start_pmd;
Marc Zyngier000d3992013-03-05 02:43:17 +0000232
Christoffer Dall4f853a72014-05-09 23:31:31 +0200233 start_pmd = pmd = pmd_offset(pud, addr);
234 do {
235 next = kvm_pmd_addr_end(addr, end);
236 if (!pmd_none(*pmd)) {
237 if (kvm_pmd_huge(*pmd)) {
Marc Zyngier363ef892014-12-19 16:48:06 +0000238 pmd_t old_pmd = *pmd;
239
Christoffer Dall4f853a72014-05-09 23:31:31 +0200240 pmd_clear(pmd);
241 kvm_tlb_flush_vmid_ipa(kvm, addr);
Marc Zyngier363ef892014-12-19 16:48:06 +0000242
243 kvm_flush_dcache_pmd(old_pmd);
244
Christoffer Dall4f853a72014-05-09 23:31:31 +0200245 put_page(virt_to_page(pmd));
246 } else {
247 unmap_ptes(kvm, pmd, addr, next);
Marc Zyngier4f728272013-04-12 19:12:05 +0100248 }
249 }
Christoffer Dall4f853a72014-05-09 23:31:31 +0200250 } while (pmd++, addr = next, addr != end);
Marc Zyngier4f728272013-04-12 19:12:05 +0100251
Christoffer Dall38f791a2014-10-10 12:14:28 +0200252 if (kvm_pmd_table_empty(kvm, start_pmd))
Christoffer Dall4f853a72014-05-09 23:31:31 +0200253 clear_pud_entry(kvm, pud, start_addr);
254}
255
256static void unmap_puds(struct kvm *kvm, pgd_t *pgd,
257 phys_addr_t addr, phys_addr_t end)
258{
259 phys_addr_t next, start_addr = addr;
260 pud_t *pud, *start_pud;
261
262 start_pud = pud = pud_offset(pgd, addr);
263 do {
264 next = kvm_pud_addr_end(addr, end);
265 if (!pud_none(*pud)) {
266 if (pud_huge(*pud)) {
Marc Zyngier363ef892014-12-19 16:48:06 +0000267 pud_t old_pud = *pud;
268
Christoffer Dall4f853a72014-05-09 23:31:31 +0200269 pud_clear(pud);
270 kvm_tlb_flush_vmid_ipa(kvm, addr);
Marc Zyngier363ef892014-12-19 16:48:06 +0000271
272 kvm_flush_dcache_pud(old_pud);
273
Christoffer Dall4f853a72014-05-09 23:31:31 +0200274 put_page(virt_to_page(pud));
275 } else {
276 unmap_pmds(kvm, pud, addr, next);
277 }
278 }
279 } while (pud++, addr = next, addr != end);
280
Christoffer Dall38f791a2014-10-10 12:14:28 +0200281 if (kvm_pud_table_empty(kvm, start_pud))
Christoffer Dall4f853a72014-05-09 23:31:31 +0200282 clear_pgd_entry(kvm, pgd, start_addr);
283}
284
285
286static void unmap_range(struct kvm *kvm, pgd_t *pgdp,
287 phys_addr_t start, u64 size)
288{
289 pgd_t *pgd;
290 phys_addr_t addr = start, end = start + size;
291 phys_addr_t next;
292
Marc Zyngier04b8dc82015-03-10 19:07:00 +0000293 pgd = pgdp + kvm_pgd_index(addr);
Christoffer Dall4f853a72014-05-09 23:31:31 +0200294 do {
295 next = kvm_pgd_addr_end(addr, end);
Mark Rutland7cbb87d2014-10-28 19:36:45 +0000296 if (!pgd_none(*pgd))
297 unmap_puds(kvm, pgd, addr, next);
Christoffer Dall4f853a72014-05-09 23:31:31 +0200298 } while (pgd++, addr = next, addr != end);
Marc Zyngier000d3992013-03-05 02:43:17 +0000299}
300
Marc Zyngier9d218a12014-01-15 12:50:23 +0000301static void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd,
302 phys_addr_t addr, phys_addr_t end)
303{
304 pte_t *pte;
305
306 pte = pte_offset_kernel(pmd, addr);
307 do {
Marc Zyngier363ef892014-12-19 16:48:06 +0000308 if (!pte_none(*pte) &&
309 (pte_val(*pte) & PAGE_S2_DEVICE) != PAGE_S2_DEVICE)
310 kvm_flush_dcache_pte(*pte);
Marc Zyngier9d218a12014-01-15 12:50:23 +0000311 } while (pte++, addr += PAGE_SIZE, addr != end);
312}
313
314static void stage2_flush_pmds(struct kvm *kvm, pud_t *pud,
315 phys_addr_t addr, phys_addr_t end)
316{
317 pmd_t *pmd;
318 phys_addr_t next;
319
320 pmd = pmd_offset(pud, addr);
321 do {
322 next = kvm_pmd_addr_end(addr, end);
323 if (!pmd_none(*pmd)) {
Marc Zyngier363ef892014-12-19 16:48:06 +0000324 if (kvm_pmd_huge(*pmd))
325 kvm_flush_dcache_pmd(*pmd);
326 else
Marc Zyngier9d218a12014-01-15 12:50:23 +0000327 stage2_flush_ptes(kvm, pmd, addr, next);
Marc Zyngier9d218a12014-01-15 12:50:23 +0000328 }
329 } while (pmd++, addr = next, addr != end);
330}
331
332static void stage2_flush_puds(struct kvm *kvm, pgd_t *pgd,
333 phys_addr_t addr, phys_addr_t end)
334{
335 pud_t *pud;
336 phys_addr_t next;
337
338 pud = pud_offset(pgd, addr);
339 do {
340 next = kvm_pud_addr_end(addr, end);
341 if (!pud_none(*pud)) {
Marc Zyngier363ef892014-12-19 16:48:06 +0000342 if (pud_huge(*pud))
343 kvm_flush_dcache_pud(*pud);
344 else
Marc Zyngier9d218a12014-01-15 12:50:23 +0000345 stage2_flush_pmds(kvm, pud, addr, next);
Marc Zyngier9d218a12014-01-15 12:50:23 +0000346 }
347 } while (pud++, addr = next, addr != end);
348}
349
350static void stage2_flush_memslot(struct kvm *kvm,
351 struct kvm_memory_slot *memslot)
352{
353 phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT;
354 phys_addr_t end = addr + PAGE_SIZE * memslot->npages;
355 phys_addr_t next;
356 pgd_t *pgd;
357
Marc Zyngier04b8dc82015-03-10 19:07:00 +0000358 pgd = kvm->arch.pgd + kvm_pgd_index(addr);
Marc Zyngier9d218a12014-01-15 12:50:23 +0000359 do {
360 next = kvm_pgd_addr_end(addr, end);
361 stage2_flush_puds(kvm, pgd, addr, next);
362 } while (pgd++, addr = next, addr != end);
363}
364
365/**
366 * stage2_flush_vm - Invalidate cache for pages mapped in stage 2
367 * @kvm: The struct kvm pointer
368 *
369 * Go through the stage 2 page tables and invalidate any cache lines
370 * backing memory already mapped to the VM.
371 */
Marc Zyngier3c1e7162014-12-19 16:05:31 +0000372static void stage2_flush_vm(struct kvm *kvm)
Marc Zyngier9d218a12014-01-15 12:50:23 +0000373{
374 struct kvm_memslots *slots;
375 struct kvm_memory_slot *memslot;
376 int idx;
377
378 idx = srcu_read_lock(&kvm->srcu);
379 spin_lock(&kvm->mmu_lock);
380
381 slots = kvm_memslots(kvm);
382 kvm_for_each_memslot(memslot, slots)
383 stage2_flush_memslot(kvm, memslot);
384
385 spin_unlock(&kvm->mmu_lock);
386 srcu_read_unlock(&kvm->srcu, idx);
387}
388
Marc Zyngier000d3992013-03-05 02:43:17 +0000389/**
Marc Zyngierd157f4a2013-04-12 19:12:07 +0100390 * free_boot_hyp_pgd - free HYP boot page tables
391 *
392 * Free the HYP boot page tables. The bounce page is also freed.
393 */
394void free_boot_hyp_pgd(void)
395{
396 mutex_lock(&kvm_hyp_pgd_mutex);
397
398 if (boot_hyp_pgd) {
Marc Zyngierd4cb9df52013-05-14 12:11:34 +0100399 unmap_range(NULL, boot_hyp_pgd, hyp_idmap_start, PAGE_SIZE);
400 unmap_range(NULL, boot_hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE);
Christoffer Dall38f791a2014-10-10 12:14:28 +0200401 free_pages((unsigned long)boot_hyp_pgd, hyp_pgd_order);
Marc Zyngierd157f4a2013-04-12 19:12:07 +0100402 boot_hyp_pgd = NULL;
403 }
404
405 if (hyp_pgd)
Marc Zyngierd4cb9df52013-05-14 12:11:34 +0100406 unmap_range(NULL, hyp_pgd, TRAMPOLINE_VA, PAGE_SIZE);
Marc Zyngierd157f4a2013-04-12 19:12:07 +0100407
Marc Zyngierd157f4a2013-04-12 19:12:07 +0100408 mutex_unlock(&kvm_hyp_pgd_mutex);
409}
410
411/**
Marc Zyngier4f728272013-04-12 19:12:05 +0100412 * free_hyp_pgds - free Hyp-mode page tables
Marc Zyngier000d3992013-03-05 02:43:17 +0000413 *
Marc Zyngier5a677ce2013-04-12 19:12:06 +0100414 * Assumes hyp_pgd is a page table used strictly in Hyp-mode and
415 * therefore contains either mappings in the kernel memory area (above
416 * PAGE_OFFSET), or device mappings in the vmalloc range (from
417 * VMALLOC_START to VMALLOC_END).
418 *
419 * boot_hyp_pgd should only map two pages for the init code.
Marc Zyngier000d3992013-03-05 02:43:17 +0000420 */
Marc Zyngier4f728272013-04-12 19:12:05 +0100421void free_hyp_pgds(void)
Marc Zyngier000d3992013-03-05 02:43:17 +0000422{
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500423 unsigned long addr;
424
Marc Zyngierd157f4a2013-04-12 19:12:07 +0100425 free_boot_hyp_pgd();
Marc Zyngier4f728272013-04-12 19:12:05 +0100426
Marc Zyngierd157f4a2013-04-12 19:12:07 +0100427 mutex_lock(&kvm_hyp_pgd_mutex);
Marc Zyngier5a677ce2013-04-12 19:12:06 +0100428
Marc Zyngier4f728272013-04-12 19:12:05 +0100429 if (hyp_pgd) {
430 for (addr = PAGE_OFFSET; virt_addr_valid(addr); addr += PGDIR_SIZE)
Marc Zyngierd4cb9df52013-05-14 12:11:34 +0100431 unmap_range(NULL, hyp_pgd, KERN_TO_HYP(addr), PGDIR_SIZE);
Marc Zyngier4f728272013-04-12 19:12:05 +0100432 for (addr = VMALLOC_START; is_vmalloc_addr((void*)addr); addr += PGDIR_SIZE)
Marc Zyngierd4cb9df52013-05-14 12:11:34 +0100433 unmap_range(NULL, hyp_pgd, KERN_TO_HYP(addr), PGDIR_SIZE);
434
Christoffer Dall38f791a2014-10-10 12:14:28 +0200435 free_pages((unsigned long)hyp_pgd, hyp_pgd_order);
Marc Zyngierd157f4a2013-04-12 19:12:07 +0100436 hyp_pgd = NULL;
Marc Zyngier4f728272013-04-12 19:12:05 +0100437 }
Ard Biesheuvele4c5a682015-03-19 16:42:28 +0000438 if (merged_hyp_pgd) {
439 clear_page(merged_hyp_pgd);
440 free_page((unsigned long)merged_hyp_pgd);
441 merged_hyp_pgd = NULL;
442 }
Marc Zyngier4f728272013-04-12 19:12:05 +0100443
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500444 mutex_unlock(&kvm_hyp_pgd_mutex);
445}
446
447static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
Marc Zyngier6060df82013-04-12 19:12:01 +0100448 unsigned long end, unsigned long pfn,
449 pgprot_t prot)
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500450{
451 pte_t *pte;
452 unsigned long addr;
453
Marc Zyngier3562c762013-04-12 19:12:02 +0100454 addr = start;
455 do {
Marc Zyngier6060df82013-04-12 19:12:01 +0100456 pte = pte_offset_kernel(pmd, addr);
457 kvm_set_pte(pte, pfn_pte(pfn, prot));
Marc Zyngier4f728272013-04-12 19:12:05 +0100458 get_page(virt_to_page(pte));
Marc Zyngier5a677ce2013-04-12 19:12:06 +0100459 kvm_flush_dcache_to_poc(pte, sizeof(*pte));
Marc Zyngier6060df82013-04-12 19:12:01 +0100460 pfn++;
Marc Zyngier3562c762013-04-12 19:12:02 +0100461 } while (addr += PAGE_SIZE, addr != end);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500462}
463
464static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
Marc Zyngier6060df82013-04-12 19:12:01 +0100465 unsigned long end, unsigned long pfn,
466 pgprot_t prot)
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500467{
468 pmd_t *pmd;
469 pte_t *pte;
470 unsigned long addr, next;
471
Marc Zyngier3562c762013-04-12 19:12:02 +0100472 addr = start;
473 do {
Marc Zyngier6060df82013-04-12 19:12:01 +0100474 pmd = pmd_offset(pud, addr);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500475
476 BUG_ON(pmd_sect(*pmd));
477
478 if (pmd_none(*pmd)) {
Marc Zyngier6060df82013-04-12 19:12:01 +0100479 pte = pte_alloc_one_kernel(NULL, addr);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500480 if (!pte) {
481 kvm_err("Cannot allocate Hyp pte\n");
482 return -ENOMEM;
483 }
484 pmd_populate_kernel(NULL, pmd, pte);
Marc Zyngier4f728272013-04-12 19:12:05 +0100485 get_page(virt_to_page(pmd));
Marc Zyngier5a677ce2013-04-12 19:12:06 +0100486 kvm_flush_dcache_to_poc(pmd, sizeof(*pmd));
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500487 }
488
489 next = pmd_addr_end(addr, end);
490
Marc Zyngier6060df82013-04-12 19:12:01 +0100491 create_hyp_pte_mappings(pmd, addr, next, pfn, prot);
492 pfn += (next - addr) >> PAGE_SHIFT;
Marc Zyngier3562c762013-04-12 19:12:02 +0100493 } while (addr = next, addr != end);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500494
495 return 0;
496}
497
Christoffer Dall38f791a2014-10-10 12:14:28 +0200498static int create_hyp_pud_mappings(pgd_t *pgd, unsigned long start,
499 unsigned long end, unsigned long pfn,
500 pgprot_t prot)
501{
502 pud_t *pud;
503 pmd_t *pmd;
504 unsigned long addr, next;
505 int ret;
506
507 addr = start;
508 do {
509 pud = pud_offset(pgd, addr);
510
511 if (pud_none_or_clear_bad(pud)) {
512 pmd = pmd_alloc_one(NULL, addr);
513 if (!pmd) {
514 kvm_err("Cannot allocate Hyp pmd\n");
515 return -ENOMEM;
516 }
517 pud_populate(NULL, pud, pmd);
518 get_page(virt_to_page(pud));
519 kvm_flush_dcache_to_poc(pud, sizeof(*pud));
520 }
521
522 next = pud_addr_end(addr, end);
523 ret = create_hyp_pmd_mappings(pud, addr, next, pfn, prot);
524 if (ret)
525 return ret;
526 pfn += (next - addr) >> PAGE_SHIFT;
527 } while (addr = next, addr != end);
528
529 return 0;
530}
531
Marc Zyngier6060df82013-04-12 19:12:01 +0100532static int __create_hyp_mappings(pgd_t *pgdp,
533 unsigned long start, unsigned long end,
534 unsigned long pfn, pgprot_t prot)
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500535{
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500536 pgd_t *pgd;
537 pud_t *pud;
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500538 unsigned long addr, next;
539 int err = 0;
540
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500541 mutex_lock(&kvm_hyp_pgd_mutex);
Marc Zyngier3562c762013-04-12 19:12:02 +0100542 addr = start & PAGE_MASK;
543 end = PAGE_ALIGN(end);
544 do {
Marc Zyngier6060df82013-04-12 19:12:01 +0100545 pgd = pgdp + pgd_index(addr);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500546
Christoffer Dall38f791a2014-10-10 12:14:28 +0200547 if (pgd_none(*pgd)) {
548 pud = pud_alloc_one(NULL, addr);
549 if (!pud) {
550 kvm_err("Cannot allocate Hyp pud\n");
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500551 err = -ENOMEM;
552 goto out;
553 }
Christoffer Dall38f791a2014-10-10 12:14:28 +0200554 pgd_populate(NULL, pgd, pud);
555 get_page(virt_to_page(pgd));
556 kvm_flush_dcache_to_poc(pgd, sizeof(*pgd));
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500557 }
558
559 next = pgd_addr_end(addr, end);
Christoffer Dall38f791a2014-10-10 12:14:28 +0200560 err = create_hyp_pud_mappings(pgd, addr, next, pfn, prot);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500561 if (err)
562 goto out;
Marc Zyngier6060df82013-04-12 19:12:01 +0100563 pfn += (next - addr) >> PAGE_SHIFT;
Marc Zyngier3562c762013-04-12 19:12:02 +0100564 } while (addr = next, addr != end);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500565out:
566 mutex_unlock(&kvm_hyp_pgd_mutex);
567 return err;
568}
569
Christoffer Dall40c27292013-11-15 13:14:12 -0800570static phys_addr_t kvm_kaddr_to_phys(void *kaddr)
571{
572 if (!is_vmalloc_addr(kaddr)) {
573 BUG_ON(!virt_addr_valid(kaddr));
574 return __pa(kaddr);
575 } else {
576 return page_to_phys(vmalloc_to_page(kaddr)) +
577 offset_in_page(kaddr);
578 }
579}
580
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500581/**
Marc Zyngier06e8c3b2012-10-28 01:09:14 +0100582 * create_hyp_mappings - duplicate a kernel virtual address range in Hyp mode
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500583 * @from: The virtual kernel start address of the range
584 * @to: The virtual kernel end address of the range (exclusive)
585 *
Marc Zyngier06e8c3b2012-10-28 01:09:14 +0100586 * The same virtual address as the kernel virtual address is also used
587 * in Hyp-mode mapping (modulo HYP_PAGE_OFFSET) to the same underlying
588 * physical pages.
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500589 */
590int create_hyp_mappings(void *from, void *to)
591{
Christoffer Dall40c27292013-11-15 13:14:12 -0800592 phys_addr_t phys_addr;
593 unsigned long virt_addr;
Marc Zyngier6060df82013-04-12 19:12:01 +0100594 unsigned long start = KERN_TO_HYP((unsigned long)from);
595 unsigned long end = KERN_TO_HYP((unsigned long)to);
596
Christoffer Dall40c27292013-11-15 13:14:12 -0800597 start = start & PAGE_MASK;
598 end = PAGE_ALIGN(end);
Marc Zyngier6060df82013-04-12 19:12:01 +0100599
Christoffer Dall40c27292013-11-15 13:14:12 -0800600 for (virt_addr = start; virt_addr < end; virt_addr += PAGE_SIZE) {
601 int err;
602
603 phys_addr = kvm_kaddr_to_phys(from + virt_addr - start);
604 err = __create_hyp_mappings(hyp_pgd, virt_addr,
605 virt_addr + PAGE_SIZE,
606 __phys_to_pfn(phys_addr),
607 PAGE_HYP);
608 if (err)
609 return err;
610 }
611
612 return 0;
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500613}
614
615/**
Marc Zyngier06e8c3b2012-10-28 01:09:14 +0100616 * create_hyp_io_mappings - duplicate a kernel IO mapping into Hyp mode
617 * @from: The kernel start VA of the range
618 * @to: The kernel end VA of the range (exclusive)
Marc Zyngier6060df82013-04-12 19:12:01 +0100619 * @phys_addr: The physical start address which gets mapped
Marc Zyngier06e8c3b2012-10-28 01:09:14 +0100620 *
621 * The resulting HYP VA is the same as the kernel VA, modulo
622 * HYP_PAGE_OFFSET.
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500623 */
Marc Zyngier6060df82013-04-12 19:12:01 +0100624int create_hyp_io_mappings(void *from, void *to, phys_addr_t phys_addr)
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500625{
Marc Zyngier6060df82013-04-12 19:12:01 +0100626 unsigned long start = KERN_TO_HYP((unsigned long)from);
627 unsigned long end = KERN_TO_HYP((unsigned long)to);
628
629 /* Check for a valid kernel IO mapping */
630 if (!is_vmalloc_addr(from) || !is_vmalloc_addr(to - 1))
631 return -EINVAL;
632
633 return __create_hyp_mappings(hyp_pgd, start, end,
634 __phys_to_pfn(phys_addr), PAGE_HYP_DEVICE);
Christoffer Dall342cd0a2013-01-20 18:28:06 -0500635}
636
Marc Zyngiera9873702015-03-10 19:06:59 +0000637/* Free the HW pgd, one page at a time */
638static void kvm_free_hwpgd(void *hwpgd)
639{
640 free_pages_exact(hwpgd, kvm_get_hwpgd_size());
641}
642
643/* Allocate the HW PGD, making sure that each page gets its own refcount */
644static void *kvm_alloc_hwpgd(void)
645{
646 unsigned int size = kvm_get_hwpgd_size();
647
648 return alloc_pages_exact(size, GFP_KERNEL | __GFP_ZERO);
649}
650
Christoffer Dalld5d81842013-01-20 18:28:07 -0500651/**
652 * kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation.
653 * @kvm: The KVM struct pointer for the VM.
654 *
655 * Allocates the 1st level table only of size defined by S2_PGD_ORDER (can
656 * support either full 40-bit input addresses or limited to 32-bit input
657 * addresses). Clears the allocated pages.
658 *
659 * Note we don't need locking here as this is only called when the VM is
660 * created, which can only be done once.
661 */
662int kvm_alloc_stage2_pgd(struct kvm *kvm)
663{
664 pgd_t *pgd;
Marc Zyngiera9873702015-03-10 19:06:59 +0000665 void *hwpgd;
Christoffer Dalld5d81842013-01-20 18:28:07 -0500666
667 if (kvm->arch.pgd != NULL) {
668 kvm_err("kvm_arch already initialized?\n");
669 return -EINVAL;
670 }
671
Marc Zyngiera9873702015-03-10 19:06:59 +0000672 hwpgd = kvm_alloc_hwpgd();
673 if (!hwpgd)
674 return -ENOMEM;
675
676 /* When the kernel uses more levels of page tables than the
677 * guest, we allocate a fake PGD and pre-populate it to point
678 * to the next-level page table, which will be the real
679 * initial page table pointed to by the VTTBR.
680 *
681 * When KVM_PREALLOC_LEVEL==2, we allocate a single page for
682 * the PMD and the kernel will use folded pud.
683 * When KVM_PREALLOC_LEVEL==1, we allocate 2 consecutive PUD
684 * pages.
685 */
Christoffer Dall38f791a2014-10-10 12:14:28 +0200686 if (KVM_PREALLOC_LEVEL > 0) {
Marc Zyngiera9873702015-03-10 19:06:59 +0000687 int i;
688
Christoffer Dall38f791a2014-10-10 12:14:28 +0200689 /*
690 * Allocate fake pgd for the page table manipulation macros to
691 * work. This is not used by the hardware and we have no
692 * alignment requirement for this allocation.
693 */
Firo Yanga5f56ba2015-04-23 11:07:40 +0100694 pgd = kmalloc(PTRS_PER_S2_PGD * sizeof(pgd_t),
695 GFP_KERNEL | __GFP_ZERO);
Marc Zyngiera9873702015-03-10 19:06:59 +0000696
697 if (!pgd) {
698 kvm_free_hwpgd(hwpgd);
699 return -ENOMEM;
700 }
701
702 /* Plug the HW PGD into the fake one. */
703 for (i = 0; i < PTRS_PER_S2_PGD; i++) {
704 if (KVM_PREALLOC_LEVEL == 1)
705 pgd_populate(NULL, pgd + i,
706 (pud_t *)hwpgd + i * PTRS_PER_PUD);
707 else if (KVM_PREALLOC_LEVEL == 2)
708 pud_populate(NULL, pud_offset(pgd, 0) + i,
709 (pmd_t *)hwpgd + i * PTRS_PER_PMD);
710 }
Christoffer Dall38f791a2014-10-10 12:14:28 +0200711 } else {
712 /*
713 * Allocate actual first-level Stage-2 page table used by the
714 * hardware for Stage-2 page table walks.
715 */
Marc Zyngiera9873702015-03-10 19:06:59 +0000716 pgd = (pgd_t *)hwpgd;
Christoffer Dall38f791a2014-10-10 12:14:28 +0200717 }
718
Marc Zyngierc62ee2b2012-10-15 11:27:37 +0100719 kvm_clean_pgd(pgd);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500720 kvm->arch.pgd = pgd;
Christoffer Dalld5d81842013-01-20 18:28:07 -0500721 return 0;
722}
723
Christoffer Dalld5d81842013-01-20 18:28:07 -0500724/**
725 * unmap_stage2_range -- Clear stage2 page table entries to unmap a range
726 * @kvm: The VM pointer
727 * @start: The intermediate physical base address of the range to unmap
728 * @size: The size of the area to unmap
729 *
730 * Clear a range of stage-2 mappings, lowering the various ref-counts. Must
731 * be called while holding mmu_lock (unless for freeing the stage2 pgd before
732 * destroying the VM), otherwise another faulting VCPU may come in and mess
733 * with things behind our backs.
734 */
735static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
736{
Marc Zyngierd4cb9df52013-05-14 12:11:34 +0100737 unmap_range(kvm, kvm->arch.pgd, start, size);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500738}
739
Christoffer Dall957db102014-11-27 10:35:03 +0100740static void stage2_unmap_memslot(struct kvm *kvm,
741 struct kvm_memory_slot *memslot)
742{
743 hva_t hva = memslot->userspace_addr;
744 phys_addr_t addr = memslot->base_gfn << PAGE_SHIFT;
745 phys_addr_t size = PAGE_SIZE * memslot->npages;
746 hva_t reg_end = hva + size;
747
748 /*
749 * A memory region could potentially cover multiple VMAs, and any holes
750 * between them, so iterate over all of them to find out if we should
751 * unmap any of them.
752 *
753 * +--------------------------------------------+
754 * +---------------+----------------+ +----------------+
755 * | : VMA 1 | VMA 2 | | VMA 3 : |
756 * +---------------+----------------+ +----------------+
757 * | memory region |
758 * +--------------------------------------------+
759 */
760 do {
761 struct vm_area_struct *vma = find_vma(current->mm, hva);
762 hva_t vm_start, vm_end;
763
764 if (!vma || vma->vm_start >= reg_end)
765 break;
766
767 /*
768 * Take the intersection of this VMA with the memory region
769 */
770 vm_start = max(hva, vma->vm_start);
771 vm_end = min(reg_end, vma->vm_end);
772
773 if (!(vma->vm_flags & VM_PFNMAP)) {
774 gpa_t gpa = addr + (vm_start - memslot->userspace_addr);
775 unmap_stage2_range(kvm, gpa, vm_end - vm_start);
776 }
777 hva = vm_end;
778 } while (hva < reg_end);
779}
780
781/**
782 * stage2_unmap_vm - Unmap Stage-2 RAM mappings
783 * @kvm: The struct kvm pointer
784 *
785 * Go through the memregions and unmap any reguler RAM
786 * backing memory already mapped to the VM.
787 */
788void stage2_unmap_vm(struct kvm *kvm)
789{
790 struct kvm_memslots *slots;
791 struct kvm_memory_slot *memslot;
792 int idx;
793
794 idx = srcu_read_lock(&kvm->srcu);
795 spin_lock(&kvm->mmu_lock);
796
797 slots = kvm_memslots(kvm);
798 kvm_for_each_memslot(memslot, slots)
799 stage2_unmap_memslot(kvm, memslot);
800
801 spin_unlock(&kvm->mmu_lock);
802 srcu_read_unlock(&kvm->srcu, idx);
803}
804
Christoffer Dalld5d81842013-01-20 18:28:07 -0500805/**
806 * kvm_free_stage2_pgd - free all stage-2 tables
807 * @kvm: The KVM struct pointer for the VM.
808 *
809 * Walks the level-1 page table pointed to by kvm->arch.pgd and frees all
810 * underlying level-2 and level-3 tables before freeing the actual level-1 table
811 * and setting the struct pointer to NULL.
812 *
813 * Note we don't need locking here as this is only called when the VM is
814 * destroyed, which can only be done once.
815 */
816void kvm_free_stage2_pgd(struct kvm *kvm)
817{
818 if (kvm->arch.pgd == NULL)
819 return;
820
821 unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE);
Marc Zyngiera9873702015-03-10 19:06:59 +0000822 kvm_free_hwpgd(kvm_get_hwpgd(kvm));
Christoffer Dall38f791a2014-10-10 12:14:28 +0200823 if (KVM_PREALLOC_LEVEL > 0)
824 kfree(kvm->arch.pgd);
Marc Zyngiera9873702015-03-10 19:06:59 +0000825
Christoffer Dalld5d81842013-01-20 18:28:07 -0500826 kvm->arch.pgd = NULL;
827}
828
Christoffer Dall38f791a2014-10-10 12:14:28 +0200829static pud_t *stage2_get_pud(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
830 phys_addr_t addr)
831{
832 pgd_t *pgd;
833 pud_t *pud;
834
Marc Zyngier04b8dc82015-03-10 19:07:00 +0000835 pgd = kvm->arch.pgd + kvm_pgd_index(addr);
Christoffer Dall38f791a2014-10-10 12:14:28 +0200836 if (WARN_ON(pgd_none(*pgd))) {
837 if (!cache)
838 return NULL;
839 pud = mmu_memory_cache_alloc(cache);
840 pgd_populate(NULL, pgd, pud);
841 get_page(virt_to_page(pgd));
842 }
843
844 return pud_offset(pgd, addr);
845}
846
Christoffer Dallad361f02012-11-01 17:14:45 +0100847static pmd_t *stage2_get_pmd(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
848 phys_addr_t addr)
Christoffer Dalld5d81842013-01-20 18:28:07 -0500849{
Christoffer Dalld5d81842013-01-20 18:28:07 -0500850 pud_t *pud;
851 pmd_t *pmd;
Christoffer Dalld5d81842013-01-20 18:28:07 -0500852
Christoffer Dall38f791a2014-10-10 12:14:28 +0200853 pud = stage2_get_pud(kvm, cache, addr);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500854 if (pud_none(*pud)) {
855 if (!cache)
Christoffer Dallad361f02012-11-01 17:14:45 +0100856 return NULL;
Christoffer Dalld5d81842013-01-20 18:28:07 -0500857 pmd = mmu_memory_cache_alloc(cache);
858 pud_populate(NULL, pud, pmd);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500859 get_page(virt_to_page(pud));
Marc Zyngierc62ee2b2012-10-15 11:27:37 +0100860 }
861
Christoffer Dallad361f02012-11-01 17:14:45 +0100862 return pmd_offset(pud, addr);
863}
Christoffer Dalld5d81842013-01-20 18:28:07 -0500864
Christoffer Dallad361f02012-11-01 17:14:45 +0100865static int stage2_set_pmd_huge(struct kvm *kvm, struct kvm_mmu_memory_cache
866 *cache, phys_addr_t addr, const pmd_t *new_pmd)
867{
868 pmd_t *pmd, old_pmd;
869
870 pmd = stage2_get_pmd(kvm, cache, addr);
871 VM_BUG_ON(!pmd);
872
873 /*
874 * Mapping in huge pages should only happen through a fault. If a
875 * page is merged into a transparent huge page, the individual
876 * subpages of that huge page should be unmapped through MMU
877 * notifiers before we get here.
878 *
879 * Merging of CompoundPages is not supported; they should become
880 * splitting first, unmapped, merged, and mapped back in on-demand.
881 */
882 VM_BUG_ON(pmd_present(*pmd) && pmd_pfn(*pmd) != pmd_pfn(*new_pmd));
883
884 old_pmd = *pmd;
885 kvm_set_pmd(pmd, *new_pmd);
886 if (pmd_present(old_pmd))
887 kvm_tlb_flush_vmid_ipa(kvm, addr);
888 else
889 get_page(virt_to_page(pmd));
890 return 0;
891}
892
893static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
Mario Smarduch15a49a42015-01-15 15:58:58 -0800894 phys_addr_t addr, const pte_t *new_pte,
895 unsigned long flags)
Christoffer Dallad361f02012-11-01 17:14:45 +0100896{
897 pmd_t *pmd;
898 pte_t *pte, old_pte;
Mario Smarduch15a49a42015-01-15 15:58:58 -0800899 bool iomap = flags & KVM_S2PTE_FLAG_IS_IOMAP;
900 bool logging_active = flags & KVM_S2_FLAG_LOGGING_ACTIVE;
901
902 VM_BUG_ON(logging_active && !cache);
Christoffer Dallad361f02012-11-01 17:14:45 +0100903
Christoffer Dall38f791a2014-10-10 12:14:28 +0200904 /* Create stage-2 page table mapping - Levels 0 and 1 */
Christoffer Dallad361f02012-11-01 17:14:45 +0100905 pmd = stage2_get_pmd(kvm, cache, addr);
906 if (!pmd) {
907 /*
908 * Ignore calls from kvm_set_spte_hva for unallocated
909 * address ranges.
910 */
911 return 0;
912 }
913
Mario Smarduch15a49a42015-01-15 15:58:58 -0800914 /*
915 * While dirty page logging - dissolve huge PMD, then continue on to
916 * allocate page.
917 */
918 if (logging_active)
919 stage2_dissolve_pmd(kvm, addr, pmd);
920
Christoffer Dallad361f02012-11-01 17:14:45 +0100921 /* Create stage-2 page mappings - Level 2 */
Christoffer Dalld5d81842013-01-20 18:28:07 -0500922 if (pmd_none(*pmd)) {
923 if (!cache)
924 return 0; /* ignore calls from kvm_set_spte_hva */
925 pte = mmu_memory_cache_alloc(cache);
Marc Zyngierc62ee2b2012-10-15 11:27:37 +0100926 kvm_clean_pte(pte);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500927 pmd_populate_kernel(NULL, pmd, pte);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500928 get_page(virt_to_page(pmd));
Marc Zyngierc62ee2b2012-10-15 11:27:37 +0100929 }
930
931 pte = pte_offset_kernel(pmd, addr);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500932
933 if (iomap && pte_present(*pte))
934 return -EFAULT;
935
936 /* Create 2nd stage page table mapping - Level 3 */
937 old_pte = *pte;
938 kvm_set_pte(pte, *new_pte);
939 if (pte_present(old_pte))
Marc Zyngier48762762013-01-28 15:27:00 +0000940 kvm_tlb_flush_vmid_ipa(kvm, addr);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500941 else
942 get_page(virt_to_page(pte));
943
944 return 0;
945}
946
947/**
948 * kvm_phys_addr_ioremap - map a device range to guest IPA
949 *
950 * @kvm: The KVM pointer
951 * @guest_ipa: The IPA at which to insert the mapping
952 * @pa: The physical address of the device
953 * @size: The size of the mapping
954 */
955int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
Ard Biesheuvelc40f2f82014-09-17 14:56:18 -0700956 phys_addr_t pa, unsigned long size, bool writable)
Christoffer Dalld5d81842013-01-20 18:28:07 -0500957{
958 phys_addr_t addr, end;
959 int ret = 0;
960 unsigned long pfn;
961 struct kvm_mmu_memory_cache cache = { 0, };
962
963 end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK;
964 pfn = __phys_to_pfn(pa);
965
966 for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) {
Marc Zyngierc62ee2b2012-10-15 11:27:37 +0100967 pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500968
Ard Biesheuvelc40f2f82014-09-17 14:56:18 -0700969 if (writable)
970 kvm_set_s2pte_writable(&pte);
971
Christoffer Dall38f791a2014-10-10 12:14:28 +0200972 ret = mmu_topup_memory_cache(&cache, KVM_MMU_CACHE_MIN_PAGES,
973 KVM_NR_MEM_OBJS);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500974 if (ret)
975 goto out;
976 spin_lock(&kvm->mmu_lock);
Mario Smarduch15a49a42015-01-15 15:58:58 -0800977 ret = stage2_set_pte(kvm, &cache, addr, &pte,
978 KVM_S2PTE_FLAG_IS_IOMAP);
Christoffer Dalld5d81842013-01-20 18:28:07 -0500979 spin_unlock(&kvm->mmu_lock);
980 if (ret)
981 goto out;
982
983 pfn++;
984 }
985
986out:
987 mmu_free_memory_cache(&cache);
988 return ret;
989}
990
Christoffer Dall9b5fdb92013-10-02 15:32:01 -0700991static bool transparent_hugepage_adjust(pfn_t *pfnp, phys_addr_t *ipap)
992{
993 pfn_t pfn = *pfnp;
994 gfn_t gfn = *ipap >> PAGE_SHIFT;
995
996 if (PageTransCompound(pfn_to_page(pfn))) {
997 unsigned long mask;
998 /*
999 * The address we faulted on is backed by a transparent huge
1000 * page. However, because we map the compound huge page and
1001 * not the individual tail page, we need to transfer the
1002 * refcount to the head page. We have to be careful that the
1003 * THP doesn't start to split while we are adjusting the
1004 * refcounts.
1005 *
1006 * We are sure this doesn't happen, because mmu_notifier_retry
1007 * was successful and we are holding the mmu_lock, so if this
1008 * THP is trying to split, it will be blocked in the mmu
1009 * notifier before touching any of the pages, specifically
1010 * before being able to call __split_huge_page_refcount().
1011 *
1012 * We can therefore safely transfer the refcount from PG_tail
1013 * to PG_head and switch the pfn from a tail page to the head
1014 * page accordingly.
1015 */
1016 mask = PTRS_PER_PMD - 1;
1017 VM_BUG_ON((gfn & mask) != (pfn & mask));
1018 if (pfn & mask) {
1019 *ipap &= PMD_MASK;
1020 kvm_release_pfn_clean(pfn);
1021 pfn &= ~mask;
1022 kvm_get_pfn(pfn);
1023 *pfnp = pfn;
1024 }
1025
1026 return true;
1027 }
1028
1029 return false;
1030}
1031
Ard Biesheuvela7d079c2014-09-09 11:27:09 +01001032static bool kvm_is_write_fault(struct kvm_vcpu *vcpu)
1033{
1034 if (kvm_vcpu_trap_is_iabt(vcpu))
1035 return false;
1036
1037 return kvm_vcpu_dabt_iswrite(vcpu);
1038}
1039
Ard Biesheuvelbb55e9b2014-11-10 09:33:55 +01001040static bool kvm_is_device_pfn(unsigned long pfn)
1041{
1042 return !pfn_valid(pfn);
1043}
1044
Mario Smarduchc6473552015-01-15 15:58:56 -08001045/**
1046 * stage2_wp_ptes - write protect PMD range
1047 * @pmd: pointer to pmd entry
1048 * @addr: range start address
1049 * @end: range end address
1050 */
1051static void stage2_wp_ptes(pmd_t *pmd, phys_addr_t addr, phys_addr_t end)
1052{
1053 pte_t *pte;
1054
1055 pte = pte_offset_kernel(pmd, addr);
1056 do {
1057 if (!pte_none(*pte)) {
1058 if (!kvm_s2pte_readonly(pte))
1059 kvm_set_s2pte_readonly(pte);
1060 }
1061 } while (pte++, addr += PAGE_SIZE, addr != end);
1062}
1063
1064/**
1065 * stage2_wp_pmds - write protect PUD range
1066 * @pud: pointer to pud entry
1067 * @addr: range start address
1068 * @end: range end address
1069 */
1070static void stage2_wp_pmds(pud_t *pud, phys_addr_t addr, phys_addr_t end)
1071{
1072 pmd_t *pmd;
1073 phys_addr_t next;
1074
1075 pmd = pmd_offset(pud, addr);
1076
1077 do {
1078 next = kvm_pmd_addr_end(addr, end);
1079 if (!pmd_none(*pmd)) {
1080 if (kvm_pmd_huge(*pmd)) {
1081 if (!kvm_s2pmd_readonly(pmd))
1082 kvm_set_s2pmd_readonly(pmd);
1083 } else {
1084 stage2_wp_ptes(pmd, addr, next);
1085 }
1086 }
1087 } while (pmd++, addr = next, addr != end);
1088}
1089
1090/**
1091 * stage2_wp_puds - write protect PGD range
1092 * @pgd: pointer to pgd entry
1093 * @addr: range start address
1094 * @end: range end address
1095 *
1096 * Process PUD entries, for a huge PUD we cause a panic.
1097 */
1098static void stage2_wp_puds(pgd_t *pgd, phys_addr_t addr, phys_addr_t end)
1099{
1100 pud_t *pud;
1101 phys_addr_t next;
1102
1103 pud = pud_offset(pgd, addr);
1104 do {
1105 next = kvm_pud_addr_end(addr, end);
1106 if (!pud_none(*pud)) {
1107 /* TODO:PUD not supported, revisit later if supported */
1108 BUG_ON(kvm_pud_huge(*pud));
1109 stage2_wp_pmds(pud, addr, next);
1110 }
1111 } while (pud++, addr = next, addr != end);
1112}
1113
1114/**
1115 * stage2_wp_range() - write protect stage2 memory region range
1116 * @kvm: The KVM pointer
1117 * @addr: Start address of range
1118 * @end: End address of range
1119 */
1120static void stage2_wp_range(struct kvm *kvm, phys_addr_t addr, phys_addr_t end)
1121{
1122 pgd_t *pgd;
1123 phys_addr_t next;
1124
Marc Zyngier04b8dc82015-03-10 19:07:00 +00001125 pgd = kvm->arch.pgd + kvm_pgd_index(addr);
Mario Smarduchc6473552015-01-15 15:58:56 -08001126 do {
1127 /*
1128 * Release kvm_mmu_lock periodically if the memory region is
1129 * large. Otherwise, we may see kernel panics with
Christoffer Dall227ea812015-01-23 10:49:31 +01001130 * CONFIG_DETECT_HUNG_TASK, CONFIG_LOCKUP_DETECTOR,
1131 * CONFIG_LOCKDEP. Additionally, holding the lock too long
Mario Smarduchc6473552015-01-15 15:58:56 -08001132 * will also starve other vCPUs.
1133 */
1134 if (need_resched() || spin_needbreak(&kvm->mmu_lock))
1135 cond_resched_lock(&kvm->mmu_lock);
1136
1137 next = kvm_pgd_addr_end(addr, end);
1138 if (pgd_present(*pgd))
1139 stage2_wp_puds(pgd, addr, next);
1140 } while (pgd++, addr = next, addr != end);
1141}
1142
1143/**
1144 * kvm_mmu_wp_memory_region() - write protect stage 2 entries for memory slot
1145 * @kvm: The KVM pointer
1146 * @slot: The memory slot to write protect
1147 *
1148 * Called to start logging dirty pages after memory region
1149 * KVM_MEM_LOG_DIRTY_PAGES operation is called. After this function returns
1150 * all present PMD and PTEs are write protected in the memory region.
1151 * Afterwards read of dirty page log can be called.
1152 *
1153 * Acquires kvm_mmu_lock. Called with kvm->slots_lock mutex acquired,
1154 * serializing operations for VM memory regions.
1155 */
1156void kvm_mmu_wp_memory_region(struct kvm *kvm, int slot)
1157{
Paolo Bonzini9f6b8022015-05-17 16:20:07 +02001158 struct kvm_memslots *slots = kvm_memslots(kvm);
1159 struct kvm_memory_slot *memslot = id_to_memslot(slots, slot);
Mario Smarduchc6473552015-01-15 15:58:56 -08001160 phys_addr_t start = memslot->base_gfn << PAGE_SHIFT;
1161 phys_addr_t end = (memslot->base_gfn + memslot->npages) << PAGE_SHIFT;
1162
1163 spin_lock(&kvm->mmu_lock);
1164 stage2_wp_range(kvm, start, end);
1165 spin_unlock(&kvm->mmu_lock);
1166 kvm_flush_remote_tlbs(kvm);
1167}
Mario Smarduch53c810c2015-01-15 15:58:57 -08001168
1169/**
Kai Huang3b0f1d02015-01-28 10:54:23 +08001170 * kvm_mmu_write_protect_pt_masked() - write protect dirty pages
Mario Smarduch53c810c2015-01-15 15:58:57 -08001171 * @kvm: The KVM pointer
1172 * @slot: The memory slot associated with mask
1173 * @gfn_offset: The gfn offset in memory slot
1174 * @mask: The mask of dirty pages at offset 'gfn_offset' in this memory
1175 * slot to be write protected
1176 *
1177 * Walks bits set in mask write protects the associated pte's. Caller must
1178 * acquire kvm_mmu_lock.
1179 */
Kai Huang3b0f1d02015-01-28 10:54:23 +08001180static void kvm_mmu_write_protect_pt_masked(struct kvm *kvm,
Mario Smarduch53c810c2015-01-15 15:58:57 -08001181 struct kvm_memory_slot *slot,
1182 gfn_t gfn_offset, unsigned long mask)
1183{
1184 phys_addr_t base_gfn = slot->base_gfn + gfn_offset;
1185 phys_addr_t start = (base_gfn + __ffs(mask)) << PAGE_SHIFT;
1186 phys_addr_t end = (base_gfn + __fls(mask) + 1) << PAGE_SHIFT;
1187
1188 stage2_wp_range(kvm, start, end);
1189}
Mario Smarduchc6473552015-01-15 15:58:56 -08001190
Kai Huang3b0f1d02015-01-28 10:54:23 +08001191/*
1192 * kvm_arch_mmu_enable_log_dirty_pt_masked - enable dirty logging for selected
1193 * dirty pages.
1194 *
1195 * It calls kvm_mmu_write_protect_pt_masked to write protect selected pages to
1196 * enable dirty logging for them.
1197 */
1198void kvm_arch_mmu_enable_log_dirty_pt_masked(struct kvm *kvm,
1199 struct kvm_memory_slot *slot,
1200 gfn_t gfn_offset, unsigned long mask)
1201{
1202 kvm_mmu_write_protect_pt_masked(kvm, slot, gfn_offset, mask);
1203}
1204
Marc Zyngier0d3e4d42015-01-05 21:13:24 +00001205static void coherent_cache_guest_page(struct kvm_vcpu *vcpu, pfn_t pfn,
1206 unsigned long size, bool uncached)
1207{
1208 __coherent_cache_guest_page(vcpu, pfn, size, uncached);
1209}
1210
Christoffer Dall94f8e642013-01-20 18:28:12 -05001211static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
Christoffer Dall98047882014-08-19 12:18:04 +02001212 struct kvm_memory_slot *memslot, unsigned long hva,
Christoffer Dall94f8e642013-01-20 18:28:12 -05001213 unsigned long fault_status)
1214{
Christoffer Dall94f8e642013-01-20 18:28:12 -05001215 int ret;
Christoffer Dall9b5fdb92013-10-02 15:32:01 -07001216 bool write_fault, writable, hugetlb = false, force_pte = false;
Christoffer Dall94f8e642013-01-20 18:28:12 -05001217 unsigned long mmu_seq;
Christoffer Dallad361f02012-11-01 17:14:45 +01001218 gfn_t gfn = fault_ipa >> PAGE_SHIFT;
Christoffer Dallad361f02012-11-01 17:14:45 +01001219 struct kvm *kvm = vcpu->kvm;
Christoffer Dall94f8e642013-01-20 18:28:12 -05001220 struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache;
Christoffer Dallad361f02012-11-01 17:14:45 +01001221 struct vm_area_struct *vma;
1222 pfn_t pfn;
Kim Phillipsb8865762014-06-26 01:45:51 +01001223 pgprot_t mem_type = PAGE_S2;
Laszlo Ersek840f4bf2014-11-17 14:58:52 +00001224 bool fault_ipa_uncached;
Mario Smarduch15a49a42015-01-15 15:58:58 -08001225 bool logging_active = memslot_is_logging(memslot);
1226 unsigned long flags = 0;
Christoffer Dall94f8e642013-01-20 18:28:12 -05001227
Ard Biesheuvela7d079c2014-09-09 11:27:09 +01001228 write_fault = kvm_is_write_fault(vcpu);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001229 if (fault_status == FSC_PERM && !write_fault) {
1230 kvm_err("Unexpected L2 read permission error\n");
1231 return -EFAULT;
1232 }
1233
Christoffer Dallad361f02012-11-01 17:14:45 +01001234 /* Let's check if we will get back a huge page backed by hugetlbfs */
1235 down_read(&current->mm->mmap_sem);
1236 vma = find_vma_intersection(current->mm, hva, hva + 1);
Ard Biesheuvel37b54402014-09-17 14:56:17 -07001237 if (unlikely(!vma)) {
1238 kvm_err("Failed to find VMA for hva 0x%lx\n", hva);
1239 up_read(&current->mm->mmap_sem);
1240 return -EFAULT;
1241 }
1242
Mario Smarduch15a49a42015-01-15 15:58:58 -08001243 if (is_vm_hugetlb_page(vma) && !logging_active) {
Christoffer Dallad361f02012-11-01 17:14:45 +01001244 hugetlb = true;
1245 gfn = (fault_ipa & PMD_MASK) >> PAGE_SHIFT;
Christoffer Dall9b5fdb92013-10-02 15:32:01 -07001246 } else {
1247 /*
Marc Zyngier136d7372013-12-13 16:56:06 +00001248 * Pages belonging to memslots that don't have the same
1249 * alignment for userspace and IPA cannot be mapped using
1250 * block descriptors even if the pages belong to a THP for
1251 * the process, because the stage-2 block descriptor will
1252 * cover more than a single THP and we loose atomicity for
1253 * unmapping, updates, and splits of the THP or other pages
1254 * in the stage-2 block range.
Christoffer Dall9b5fdb92013-10-02 15:32:01 -07001255 */
Marc Zyngier136d7372013-12-13 16:56:06 +00001256 if ((memslot->userspace_addr & ~PMD_MASK) !=
1257 ((memslot->base_gfn << PAGE_SHIFT) & ~PMD_MASK))
Christoffer Dall9b5fdb92013-10-02 15:32:01 -07001258 force_pte = true;
Christoffer Dallad361f02012-11-01 17:14:45 +01001259 }
1260 up_read(&current->mm->mmap_sem);
1261
Christoffer Dall94f8e642013-01-20 18:28:12 -05001262 /* We need minimum second+third level pages */
Christoffer Dall38f791a2014-10-10 12:14:28 +02001263 ret = mmu_topup_memory_cache(memcache, KVM_MMU_CACHE_MIN_PAGES,
1264 KVM_NR_MEM_OBJS);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001265 if (ret)
1266 return ret;
1267
1268 mmu_seq = vcpu->kvm->mmu_notifier_seq;
1269 /*
1270 * Ensure the read of mmu_notifier_seq happens before we call
1271 * gfn_to_pfn_prot (which calls get_user_pages), so that we don't risk
1272 * the page we just got a reference to gets unmapped before we have a
1273 * chance to grab the mmu_lock, which ensure that if the page gets
1274 * unmapped afterwards, the call to kvm_unmap_hva will take it away
1275 * from us again properly. This smp_rmb() interacts with the smp_wmb()
1276 * in kvm_mmu_notifier_invalidate_<page|range_end>.
1277 */
1278 smp_rmb();
1279
Christoffer Dallad361f02012-11-01 17:14:45 +01001280 pfn = gfn_to_pfn_prot(kvm, gfn, write_fault, &writable);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001281 if (is_error_pfn(pfn))
1282 return -EFAULT;
1283
Mario Smarduch15a49a42015-01-15 15:58:58 -08001284 if (kvm_is_device_pfn(pfn)) {
Kim Phillipsb8865762014-06-26 01:45:51 +01001285 mem_type = PAGE_S2_DEVICE;
Mario Smarduch15a49a42015-01-15 15:58:58 -08001286 flags |= KVM_S2PTE_FLAG_IS_IOMAP;
1287 } else if (logging_active) {
1288 /*
1289 * Faults on pages in a memslot with logging enabled
1290 * should not be mapped with huge pages (it introduces churn
1291 * and performance degradation), so force a pte mapping.
1292 */
1293 force_pte = true;
1294 flags |= KVM_S2_FLAG_LOGGING_ACTIVE;
1295
1296 /*
1297 * Only actually map the page as writable if this was a write
1298 * fault.
1299 */
1300 if (!write_fault)
1301 writable = false;
1302 }
Kim Phillipsb8865762014-06-26 01:45:51 +01001303
Christoffer Dallad361f02012-11-01 17:14:45 +01001304 spin_lock(&kvm->mmu_lock);
1305 if (mmu_notifier_retry(kvm, mmu_seq))
Christoffer Dall94f8e642013-01-20 18:28:12 -05001306 goto out_unlock;
Mario Smarduch15a49a42015-01-15 15:58:58 -08001307
Christoffer Dall9b5fdb92013-10-02 15:32:01 -07001308 if (!hugetlb && !force_pte)
1309 hugetlb = transparent_hugepage_adjust(&pfn, &fault_ipa);
Christoffer Dallad361f02012-11-01 17:14:45 +01001310
Ard Biesheuvel849260c2014-11-17 14:58:53 +00001311 fault_ipa_uncached = memslot->flags & KVM_MEMSLOT_INCOHERENT;
Laszlo Ersek840f4bf2014-11-17 14:58:52 +00001312
Christoffer Dallad361f02012-11-01 17:14:45 +01001313 if (hugetlb) {
Kim Phillipsb8865762014-06-26 01:45:51 +01001314 pmd_t new_pmd = pfn_pmd(pfn, mem_type);
Christoffer Dallad361f02012-11-01 17:14:45 +01001315 new_pmd = pmd_mkhuge(new_pmd);
1316 if (writable) {
1317 kvm_set_s2pmd_writable(&new_pmd);
1318 kvm_set_pfn_dirty(pfn);
1319 }
Marc Zyngier0d3e4d42015-01-05 21:13:24 +00001320 coherent_cache_guest_page(vcpu, pfn, PMD_SIZE, fault_ipa_uncached);
Christoffer Dallad361f02012-11-01 17:14:45 +01001321 ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd);
1322 } else {
Kim Phillipsb8865762014-06-26 01:45:51 +01001323 pte_t new_pte = pfn_pte(pfn, mem_type);
Mario Smarduch15a49a42015-01-15 15:58:58 -08001324
Christoffer Dallad361f02012-11-01 17:14:45 +01001325 if (writable) {
1326 kvm_set_s2pte_writable(&new_pte);
1327 kvm_set_pfn_dirty(pfn);
Mario Smarduch15a49a42015-01-15 15:58:58 -08001328 mark_page_dirty(kvm, gfn);
Christoffer Dallad361f02012-11-01 17:14:45 +01001329 }
Marc Zyngier0d3e4d42015-01-05 21:13:24 +00001330 coherent_cache_guest_page(vcpu, pfn, PAGE_SIZE, fault_ipa_uncached);
Mario Smarduch15a49a42015-01-15 15:58:58 -08001331 ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte, flags);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001332 }
Christoffer Dallad361f02012-11-01 17:14:45 +01001333
Christoffer Dall94f8e642013-01-20 18:28:12 -05001334out_unlock:
Christoffer Dallad361f02012-11-01 17:14:45 +01001335 spin_unlock(&kvm->mmu_lock);
Marc Zyngier35307b92015-03-12 18:16:51 +00001336 kvm_set_pfn_accessed(pfn);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001337 kvm_release_pfn_clean(pfn);
Christoffer Dallad361f02012-11-01 17:14:45 +01001338 return ret;
Christoffer Dall94f8e642013-01-20 18:28:12 -05001339}
1340
Marc Zyngieraeda9132015-03-12 18:16:52 +00001341/*
1342 * Resolve the access fault by making the page young again.
1343 * Note that because the faulting entry is guaranteed not to be
1344 * cached in the TLB, we don't need to invalidate anything.
1345 */
1346static void handle_access_fault(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa)
1347{
1348 pmd_t *pmd;
1349 pte_t *pte;
1350 pfn_t pfn;
1351 bool pfn_valid = false;
1352
1353 trace_kvm_access_fault(fault_ipa);
1354
1355 spin_lock(&vcpu->kvm->mmu_lock);
1356
1357 pmd = stage2_get_pmd(vcpu->kvm, NULL, fault_ipa);
1358 if (!pmd || pmd_none(*pmd)) /* Nothing there */
1359 goto out;
1360
1361 if (kvm_pmd_huge(*pmd)) { /* THP, HugeTLB */
1362 *pmd = pmd_mkyoung(*pmd);
1363 pfn = pmd_pfn(*pmd);
1364 pfn_valid = true;
1365 goto out;
1366 }
1367
1368 pte = pte_offset_kernel(pmd, fault_ipa);
1369 if (pte_none(*pte)) /* Nothing there either */
1370 goto out;
1371
1372 *pte = pte_mkyoung(*pte); /* Just a page... */
1373 pfn = pte_pfn(*pte);
1374 pfn_valid = true;
1375out:
1376 spin_unlock(&vcpu->kvm->mmu_lock);
1377 if (pfn_valid)
1378 kvm_set_pfn_accessed(pfn);
1379}
1380
Christoffer Dall94f8e642013-01-20 18:28:12 -05001381/**
1382 * kvm_handle_guest_abort - handles all 2nd stage aborts
1383 * @vcpu: the VCPU pointer
1384 * @run: the kvm_run structure
1385 *
1386 * Any abort that gets to the host is almost guaranteed to be caused by a
1387 * missing second stage translation table entry, which can mean that either the
1388 * guest simply needs more memory and we must allocate an appropriate page or it
1389 * can mean that the guest tried to access I/O memory, which is emulated by user
1390 * space. The distinction is based on the IPA causing the fault and whether this
1391 * memory region has been registered as standard RAM by user space.
1392 */
Christoffer Dall342cd0a2013-01-20 18:28:06 -05001393int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
1394{
Christoffer Dall94f8e642013-01-20 18:28:12 -05001395 unsigned long fault_status;
1396 phys_addr_t fault_ipa;
1397 struct kvm_memory_slot *memslot;
Christoffer Dall98047882014-08-19 12:18:04 +02001398 unsigned long hva;
1399 bool is_iabt, write_fault, writable;
Christoffer Dall94f8e642013-01-20 18:28:12 -05001400 gfn_t gfn;
1401 int ret, idx;
1402
Marc Zyngier52d1dba2012-10-15 10:33:38 +01001403 is_iabt = kvm_vcpu_trap_is_iabt(vcpu);
Marc Zyngier7393b592012-09-17 19:27:09 +01001404 fault_ipa = kvm_vcpu_get_fault_ipa(vcpu);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001405
Marc Zyngier7393b592012-09-17 19:27:09 +01001406 trace_kvm_guest_fault(*vcpu_pc(vcpu), kvm_vcpu_get_hsr(vcpu),
1407 kvm_vcpu_get_hfar(vcpu), fault_ipa);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001408
1409 /* Check the stage-2 fault is trans. fault or write fault */
Christoffer Dall0496daa52014-09-26 12:29:34 +02001410 fault_status = kvm_vcpu_trap_get_fault_type(vcpu);
Marc Zyngier35307b92015-03-12 18:16:51 +00001411 if (fault_status != FSC_FAULT && fault_status != FSC_PERM &&
1412 fault_status != FSC_ACCESS) {
Christoffer Dall0496daa52014-09-26 12:29:34 +02001413 kvm_err("Unsupported FSC: EC=%#x xFSC=%#lx ESR_EL2=%#lx\n",
1414 kvm_vcpu_trap_get_class(vcpu),
1415 (unsigned long)kvm_vcpu_trap_get_fault(vcpu),
1416 (unsigned long)kvm_vcpu_get_hsr(vcpu));
Christoffer Dall94f8e642013-01-20 18:28:12 -05001417 return -EFAULT;
1418 }
1419
1420 idx = srcu_read_lock(&vcpu->kvm->srcu);
1421
1422 gfn = fault_ipa >> PAGE_SHIFT;
Christoffer Dall98047882014-08-19 12:18:04 +02001423 memslot = gfn_to_memslot(vcpu->kvm, gfn);
1424 hva = gfn_to_hva_memslot_prot(memslot, gfn, &writable);
Ard Biesheuvela7d079c2014-09-09 11:27:09 +01001425 write_fault = kvm_is_write_fault(vcpu);
Christoffer Dall98047882014-08-19 12:18:04 +02001426 if (kvm_is_error_hva(hva) || (write_fault && !writable)) {
Christoffer Dall94f8e642013-01-20 18:28:12 -05001427 if (is_iabt) {
1428 /* Prefetch Abort on I/O address */
Marc Zyngier7393b592012-09-17 19:27:09 +01001429 kvm_inject_pabt(vcpu, kvm_vcpu_get_hfar(vcpu));
Christoffer Dall94f8e642013-01-20 18:28:12 -05001430 ret = 1;
1431 goto out_unlock;
1432 }
1433
Marc Zyngiercfe39502012-12-12 14:42:09 +00001434 /*
1435 * The IPA is reported as [MAX:12], so we need to
1436 * complement it with the bottom 12 bits from the
1437 * faulting VA. This is always 12 bits, irrespective
1438 * of the page size.
1439 */
1440 fault_ipa |= kvm_vcpu_get_hfar(vcpu) & ((1 << 12) - 1);
Christoffer Dall45e96ea2013-01-20 18:43:58 -05001441 ret = io_mem_abort(vcpu, run, fault_ipa);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001442 goto out_unlock;
1443 }
1444
Christoffer Dallc3058d52014-10-10 12:14:29 +02001445 /* Userspace should not be able to register out-of-bounds IPAs */
1446 VM_BUG_ON(fault_ipa >= KVM_PHYS_SIZE);
1447
Marc Zyngieraeda9132015-03-12 18:16:52 +00001448 if (fault_status == FSC_ACCESS) {
1449 handle_access_fault(vcpu, fault_ipa);
1450 ret = 1;
1451 goto out_unlock;
1452 }
1453
Christoffer Dall98047882014-08-19 12:18:04 +02001454 ret = user_mem_abort(vcpu, fault_ipa, memslot, hva, fault_status);
Christoffer Dall94f8e642013-01-20 18:28:12 -05001455 if (ret == 0)
1456 ret = 1;
1457out_unlock:
1458 srcu_read_unlock(&vcpu->kvm->srcu, idx);
1459 return ret;
Christoffer Dall342cd0a2013-01-20 18:28:06 -05001460}
1461
Marc Zyngier1d2ebac2015-03-12 18:16:50 +00001462static int handle_hva_to_gpa(struct kvm *kvm,
1463 unsigned long start,
1464 unsigned long end,
1465 int (*handler)(struct kvm *kvm,
1466 gpa_t gpa, void *data),
1467 void *data)
Christoffer Dalld5d81842013-01-20 18:28:07 -05001468{
1469 struct kvm_memslots *slots;
1470 struct kvm_memory_slot *memslot;
Marc Zyngier1d2ebac2015-03-12 18:16:50 +00001471 int ret = 0;
Christoffer Dalld5d81842013-01-20 18:28:07 -05001472
1473 slots = kvm_memslots(kvm);
1474
1475 /* we only care about the pages that the guest sees */
1476 kvm_for_each_memslot(memslot, slots) {
1477 unsigned long hva_start, hva_end;
1478 gfn_t gfn, gfn_end;
1479
1480 hva_start = max(start, memslot->userspace_addr);
1481 hva_end = min(end, memslot->userspace_addr +
1482 (memslot->npages << PAGE_SHIFT));
1483 if (hva_start >= hva_end)
1484 continue;
1485
1486 /*
1487 * {gfn(page) | page intersects with [hva_start, hva_end)} =
1488 * {gfn_start, gfn_start+1, ..., gfn_end-1}.
1489 */
1490 gfn = hva_to_gfn_memslot(hva_start, memslot);
1491 gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);
1492
1493 for (; gfn < gfn_end; ++gfn) {
1494 gpa_t gpa = gfn << PAGE_SHIFT;
Marc Zyngier1d2ebac2015-03-12 18:16:50 +00001495 ret |= handler(kvm, gpa, data);
Christoffer Dalld5d81842013-01-20 18:28:07 -05001496 }
1497 }
Marc Zyngier1d2ebac2015-03-12 18:16:50 +00001498
1499 return ret;
Christoffer Dalld5d81842013-01-20 18:28:07 -05001500}
1501
Marc Zyngier1d2ebac2015-03-12 18:16:50 +00001502static int kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
Christoffer Dalld5d81842013-01-20 18:28:07 -05001503{
1504 unmap_stage2_range(kvm, gpa, PAGE_SIZE);
Marc Zyngier1d2ebac2015-03-12 18:16:50 +00001505 return 0;
Christoffer Dalld5d81842013-01-20 18:28:07 -05001506}
1507
1508int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
1509{
1510 unsigned long end = hva + PAGE_SIZE;
1511
1512 if (!kvm->arch.pgd)
1513 return 0;
1514
1515 trace_kvm_unmap_hva(hva);
1516 handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler, NULL);
1517 return 0;
1518}
1519
1520int kvm_unmap_hva_range(struct kvm *kvm,
1521 unsigned long start, unsigned long end)
1522{
1523 if (!kvm->arch.pgd)
1524 return 0;
1525
1526 trace_kvm_unmap_hva_range(start, end);
1527 handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);
1528 return 0;
1529}
1530
Marc Zyngier1d2ebac2015-03-12 18:16:50 +00001531static int kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, void *data)
Christoffer Dalld5d81842013-01-20 18:28:07 -05001532{
1533 pte_t *pte = (pte_t *)data;
1534
Mario Smarduch15a49a42015-01-15 15:58:58 -08001535 /*
1536 * We can always call stage2_set_pte with KVM_S2PTE_FLAG_LOGGING_ACTIVE
1537 * flag clear because MMU notifiers will have unmapped a huge PMD before
1538 * calling ->change_pte() (which in turn calls kvm_set_spte_hva()) and
1539 * therefore stage2_set_pte() never needs to clear out a huge PMD
1540 * through this calling path.
1541 */
1542 stage2_set_pte(kvm, NULL, gpa, pte, 0);
Marc Zyngier1d2ebac2015-03-12 18:16:50 +00001543 return 0;
Christoffer Dalld5d81842013-01-20 18:28:07 -05001544}
1545
1546
1547void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
1548{
1549 unsigned long end = hva + PAGE_SIZE;
1550 pte_t stage2_pte;
1551
1552 if (!kvm->arch.pgd)
1553 return;
1554
1555 trace_kvm_set_spte_hva(hva);
1556 stage2_pte = pfn_pte(pte_pfn(pte), PAGE_S2);
1557 handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte);
1558}
1559
Marc Zyngier35307b92015-03-12 18:16:51 +00001560static int kvm_age_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
1561{
1562 pmd_t *pmd;
1563 pte_t *pte;
1564
1565 pmd = stage2_get_pmd(kvm, NULL, gpa);
1566 if (!pmd || pmd_none(*pmd)) /* Nothing there */
1567 return 0;
1568
1569 if (kvm_pmd_huge(*pmd)) { /* THP, HugeTLB */
1570 if (pmd_young(*pmd)) {
1571 *pmd = pmd_mkold(*pmd);
1572 return 1;
1573 }
1574
1575 return 0;
1576 }
1577
1578 pte = pte_offset_kernel(pmd, gpa);
1579 if (pte_none(*pte))
1580 return 0;
1581
1582 if (pte_young(*pte)) {
1583 *pte = pte_mkold(*pte); /* Just a page... */
1584 return 1;
1585 }
1586
1587 return 0;
1588}
1589
1590static int kvm_test_age_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
1591{
1592 pmd_t *pmd;
1593 pte_t *pte;
1594
1595 pmd = stage2_get_pmd(kvm, NULL, gpa);
1596 if (!pmd || pmd_none(*pmd)) /* Nothing there */
1597 return 0;
1598
1599 if (kvm_pmd_huge(*pmd)) /* THP, HugeTLB */
1600 return pmd_young(*pmd);
1601
1602 pte = pte_offset_kernel(pmd, gpa);
1603 if (!pte_none(*pte)) /* Just a page... */
1604 return pte_young(*pte);
1605
1606 return 0;
1607}
1608
1609int kvm_age_hva(struct kvm *kvm, unsigned long start, unsigned long end)
1610{
1611 trace_kvm_age_hva(start, end);
1612 return handle_hva_to_gpa(kvm, start, end, kvm_age_hva_handler, NULL);
1613}
1614
1615int kvm_test_age_hva(struct kvm *kvm, unsigned long hva)
1616{
1617 trace_kvm_test_age_hva(hva);
1618 return handle_hva_to_gpa(kvm, hva, hva, kvm_test_age_hva_handler, NULL);
1619}
1620
Christoffer Dalld5d81842013-01-20 18:28:07 -05001621void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu)
1622{
1623 mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
1624}
1625
Christoffer Dall342cd0a2013-01-20 18:28:06 -05001626phys_addr_t kvm_mmu_get_httbr(void)
1627{
Ard Biesheuvele4c5a682015-03-19 16:42:28 +00001628 if (__kvm_cpu_uses_extended_idmap())
1629 return virt_to_phys(merged_hyp_pgd);
1630 else
1631 return virt_to_phys(hyp_pgd);
Christoffer Dall342cd0a2013-01-20 18:28:06 -05001632}
1633
Marc Zyngier5a677ce2013-04-12 19:12:06 +01001634phys_addr_t kvm_mmu_get_boot_httbr(void)
1635{
Ard Biesheuvele4c5a682015-03-19 16:42:28 +00001636 if (__kvm_cpu_uses_extended_idmap())
1637 return virt_to_phys(merged_hyp_pgd);
1638 else
1639 return virt_to_phys(boot_hyp_pgd);
Marc Zyngier5a677ce2013-04-12 19:12:06 +01001640}
1641
1642phys_addr_t kvm_get_idmap_vector(void)
1643{
1644 return hyp_idmap_vector;
1645}
1646
Christoffer Dall342cd0a2013-01-20 18:28:06 -05001647int kvm_mmu_init(void)
1648{
Marc Zyngier2fb41052013-04-12 19:12:03 +01001649 int err;
1650
Santosh Shilimkar4fda3422013-11-19 14:59:12 -05001651 hyp_idmap_start = kvm_virt_to_phys(__hyp_idmap_text_start);
1652 hyp_idmap_end = kvm_virt_to_phys(__hyp_idmap_text_end);
1653 hyp_idmap_vector = kvm_virt_to_phys(__kvm_hyp_init);
Marc Zyngier5a677ce2013-04-12 19:12:06 +01001654
Ard Biesheuvel06f75a12015-03-19 16:42:26 +00001655 /*
1656 * We rely on the linker script to ensure at build time that the HYP
1657 * init code does not cross a page boundary.
1658 */
1659 BUG_ON((hyp_idmap_start ^ (hyp_idmap_end - 1)) & PAGE_MASK);
Marc Zyngier5a677ce2013-04-12 19:12:06 +01001660
Christoffer Dall38f791a2014-10-10 12:14:28 +02001661 hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order);
1662 boot_hyp_pgd = (pgd_t *)__get_free_pages(GFP_KERNEL | __GFP_ZERO, hyp_pgd_order);
Mark Salter5d4e08c2014-03-28 14:25:19 +00001663
Marc Zyngier5a677ce2013-04-12 19:12:06 +01001664 if (!hyp_pgd || !boot_hyp_pgd) {
Christoffer Dalld5d81842013-01-20 18:28:07 -05001665 kvm_err("Hyp mode PGD not allocated\n");
Marc Zyngier2fb41052013-04-12 19:12:03 +01001666 err = -ENOMEM;
1667 goto out;
1668 }
1669
1670 /* Create the idmap in the boot page tables */
1671 err = __create_hyp_mappings(boot_hyp_pgd,
1672 hyp_idmap_start, hyp_idmap_end,
1673 __phys_to_pfn(hyp_idmap_start),
1674 PAGE_HYP);
1675
1676 if (err) {
1677 kvm_err("Failed to idmap %lx-%lx\n",
1678 hyp_idmap_start, hyp_idmap_end);
1679 goto out;
Christoffer Dalld5d81842013-01-20 18:28:07 -05001680 }
1681
Ard Biesheuvele4c5a682015-03-19 16:42:28 +00001682 if (__kvm_cpu_uses_extended_idmap()) {
1683 merged_hyp_pgd = (pgd_t *)__get_free_page(GFP_KERNEL | __GFP_ZERO);
1684 if (!merged_hyp_pgd) {
1685 kvm_err("Failed to allocate extra HYP pgd\n");
1686 goto out;
1687 }
1688 __kvm_extend_hypmap(boot_hyp_pgd, hyp_pgd, merged_hyp_pgd,
1689 hyp_idmap_start);
1690 return 0;
1691 }
1692
Marc Zyngier5a677ce2013-04-12 19:12:06 +01001693 /* Map the very same page at the trampoline VA */
1694 err = __create_hyp_mappings(boot_hyp_pgd,
1695 TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE,
1696 __phys_to_pfn(hyp_idmap_start),
1697 PAGE_HYP);
1698 if (err) {
1699 kvm_err("Failed to map trampoline @%lx into boot HYP pgd\n",
1700 TRAMPOLINE_VA);
1701 goto out;
1702 }
1703
1704 /* Map the same page again into the runtime page tables */
1705 err = __create_hyp_mappings(hyp_pgd,
1706 TRAMPOLINE_VA, TRAMPOLINE_VA + PAGE_SIZE,
1707 __phys_to_pfn(hyp_idmap_start),
1708 PAGE_HYP);
1709 if (err) {
1710 kvm_err("Failed to map trampoline @%lx into runtime HYP pgd\n",
1711 TRAMPOLINE_VA);
1712 goto out;
1713 }
1714
Christoffer Dalld5d81842013-01-20 18:28:07 -05001715 return 0;
Marc Zyngier2fb41052013-04-12 19:12:03 +01001716out:
Marc Zyngier4f728272013-04-12 19:12:05 +01001717 free_hyp_pgds();
Marc Zyngier2fb41052013-04-12 19:12:03 +01001718 return err;
Christoffer Dall342cd0a2013-01-20 18:28:06 -05001719}
Eric Augerdf6ce242014-06-06 11:10:23 +02001720
1721void kvm_arch_commit_memory_region(struct kvm *kvm,
Paolo Bonzini09170a42015-05-18 13:59:39 +02001722 const struct kvm_userspace_memory_region *mem,
Eric Augerdf6ce242014-06-06 11:10:23 +02001723 const struct kvm_memory_slot *old,
Paolo Bonzinif36f3f22015-05-18 13:20:23 +02001724 const struct kvm_memory_slot *new,
Eric Augerdf6ce242014-06-06 11:10:23 +02001725 enum kvm_mr_change change)
1726{
Mario Smarduchc6473552015-01-15 15:58:56 -08001727 /*
1728 * At this point memslot has been committed and there is an
1729 * allocated dirty_bitmap[], dirty pages will be be tracked while the
1730 * memory slot is write protected.
1731 */
1732 if (change != KVM_MR_DELETE && mem->flags & KVM_MEM_LOG_DIRTY_PAGES)
1733 kvm_mmu_wp_memory_region(kvm, mem->slot);
Eric Augerdf6ce242014-06-06 11:10:23 +02001734}
1735
1736int kvm_arch_prepare_memory_region(struct kvm *kvm,
1737 struct kvm_memory_slot *memslot,
Paolo Bonzini09170a42015-05-18 13:59:39 +02001738 const struct kvm_userspace_memory_region *mem,
Eric Augerdf6ce242014-06-06 11:10:23 +02001739 enum kvm_mr_change change)
1740{
Ard Biesheuvel8eef9122014-10-10 17:00:32 +02001741 hva_t hva = mem->userspace_addr;
1742 hva_t reg_end = hva + mem->memory_size;
1743 bool writable = !(mem->flags & KVM_MEM_READONLY);
1744 int ret = 0;
1745
Mario Smarduch15a49a42015-01-15 15:58:58 -08001746 if (change != KVM_MR_CREATE && change != KVM_MR_MOVE &&
1747 change != KVM_MR_FLAGS_ONLY)
Ard Biesheuvel8eef9122014-10-10 17:00:32 +02001748 return 0;
1749
1750 /*
Christoffer Dallc3058d52014-10-10 12:14:29 +02001751 * Prevent userspace from creating a memory region outside of the IPA
1752 * space addressable by the KVM guest IPA space.
1753 */
1754 if (memslot->base_gfn + memslot->npages >=
1755 (KVM_PHYS_SIZE >> PAGE_SHIFT))
1756 return -EFAULT;
1757
1758 /*
Ard Biesheuvel8eef9122014-10-10 17:00:32 +02001759 * A memory region could potentially cover multiple VMAs, and any holes
1760 * between them, so iterate over all of them to find out if we can map
1761 * any of them right now.
1762 *
1763 * +--------------------------------------------+
1764 * +---------------+----------------+ +----------------+
1765 * | : VMA 1 | VMA 2 | | VMA 3 : |
1766 * +---------------+----------------+ +----------------+
1767 * | memory region |
1768 * +--------------------------------------------+
1769 */
1770 do {
1771 struct vm_area_struct *vma = find_vma(current->mm, hva);
1772 hva_t vm_start, vm_end;
1773
1774 if (!vma || vma->vm_start >= reg_end)
1775 break;
1776
1777 /*
1778 * Mapping a read-only VMA is only allowed if the
1779 * memory region is configured as read-only.
1780 */
1781 if (writable && !(vma->vm_flags & VM_WRITE)) {
1782 ret = -EPERM;
1783 break;
1784 }
1785
1786 /*
1787 * Take the intersection of this VMA with the memory region
1788 */
1789 vm_start = max(hva, vma->vm_start);
1790 vm_end = min(reg_end, vma->vm_end);
1791
1792 if (vma->vm_flags & VM_PFNMAP) {
1793 gpa_t gpa = mem->guest_phys_addr +
1794 (vm_start - mem->userspace_addr);
Marek Majtykaca09f022015-09-16 12:04:55 +02001795 phys_addr_t pa;
1796
1797 pa = (phys_addr_t)vma->vm_pgoff << PAGE_SHIFT;
1798 pa += vm_start - vma->vm_start;
Ard Biesheuvel8eef9122014-10-10 17:00:32 +02001799
Mario Smarduch15a49a42015-01-15 15:58:58 -08001800 /* IO region dirty page logging not allowed */
1801 if (memslot->flags & KVM_MEM_LOG_DIRTY_PAGES)
1802 return -EINVAL;
1803
Ard Biesheuvel8eef9122014-10-10 17:00:32 +02001804 ret = kvm_phys_addr_ioremap(kvm, gpa, pa,
1805 vm_end - vm_start,
1806 writable);
1807 if (ret)
1808 break;
1809 }
1810 hva = vm_end;
1811 } while (hva < reg_end);
1812
Mario Smarduch15a49a42015-01-15 15:58:58 -08001813 if (change == KVM_MR_FLAGS_ONLY)
1814 return ret;
1815
Ard Biesheuvel849260c2014-11-17 14:58:53 +00001816 spin_lock(&kvm->mmu_lock);
1817 if (ret)
Ard Biesheuvel8eef9122014-10-10 17:00:32 +02001818 unmap_stage2_range(kvm, mem->guest_phys_addr, mem->memory_size);
Ard Biesheuvel849260c2014-11-17 14:58:53 +00001819 else
1820 stage2_flush_memslot(kvm, memslot);
1821 spin_unlock(&kvm->mmu_lock);
Ard Biesheuvel8eef9122014-10-10 17:00:32 +02001822 return ret;
Eric Augerdf6ce242014-06-06 11:10:23 +02001823}
1824
1825void kvm_arch_free_memslot(struct kvm *kvm, struct kvm_memory_slot *free,
1826 struct kvm_memory_slot *dont)
1827{
1828}
1829
1830int kvm_arch_create_memslot(struct kvm *kvm, struct kvm_memory_slot *slot,
1831 unsigned long npages)
1832{
Ard Biesheuvel849260c2014-11-17 14:58:53 +00001833 /*
1834 * Readonly memslots are not incoherent with the caches by definition,
1835 * but in practice, they are used mostly to emulate ROMs or NOR flashes
1836 * that the guest may consider devices and hence map as uncached.
1837 * To prevent incoherency issues in these cases, tag all readonly
1838 * regions as incoherent.
1839 */
1840 if (slot->flags & KVM_MEM_READONLY)
1841 slot->flags |= KVM_MEMSLOT_INCOHERENT;
Eric Augerdf6ce242014-06-06 11:10:23 +02001842 return 0;
1843}
1844
Paolo Bonzini15f46012015-05-17 21:26:08 +02001845void kvm_arch_memslots_updated(struct kvm *kvm, struct kvm_memslots *slots)
Eric Augerdf6ce242014-06-06 11:10:23 +02001846{
1847}
1848
1849void kvm_arch_flush_shadow_all(struct kvm *kvm)
1850{
1851}
1852
1853void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
1854 struct kvm_memory_slot *slot)
1855{
Ard Biesheuvel8eef9122014-10-10 17:00:32 +02001856 gpa_t gpa = slot->base_gfn << PAGE_SHIFT;
1857 phys_addr_t size = slot->npages << PAGE_SHIFT;
1858
1859 spin_lock(&kvm->mmu_lock);
1860 unmap_stage2_range(kvm, gpa, size);
1861 spin_unlock(&kvm->mmu_lock);
Eric Augerdf6ce242014-06-06 11:10:23 +02001862}
Marc Zyngier3c1e7162014-12-19 16:05:31 +00001863
1864/*
1865 * See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
1866 *
1867 * Main problems:
1868 * - S/W ops are local to a CPU (not broadcast)
1869 * - We have line migration behind our back (speculation)
1870 * - System caches don't support S/W at all (damn!)
1871 *
1872 * In the face of the above, the best we can do is to try and convert
1873 * S/W ops to VA ops. Because the guest is not allowed to infer the
1874 * S/W to PA mapping, it can only use S/W to nuke the whole cache,
1875 * which is a rather good thing for us.
1876 *
1877 * Also, it is only used when turning caches on/off ("The expected
1878 * usage of the cache maintenance instructions that operate by set/way
1879 * is associated with the cache maintenance instructions associated
1880 * with the powerdown and powerup of caches, if this is required by
1881 * the implementation.").
1882 *
1883 * We use the following policy:
1884 *
1885 * - If we trap a S/W operation, we enable VM trapping to detect
1886 * caches being turned on/off, and do a full clean.
1887 *
1888 * - We flush the caches on both caches being turned on and off.
1889 *
1890 * - Once the caches are enabled, we stop trapping VM ops.
1891 */
1892void kvm_set_way_flush(struct kvm_vcpu *vcpu)
1893{
1894 unsigned long hcr = vcpu_get_hcr(vcpu);
1895
1896 /*
1897 * If this is the first time we do a S/W operation
1898 * (i.e. HCR_TVM not set) flush the whole memory, and set the
1899 * VM trapping.
1900 *
1901 * Otherwise, rely on the VM trapping to wait for the MMU +
1902 * Caches to be turned off. At that point, we'll be able to
1903 * clean the caches again.
1904 */
1905 if (!(hcr & HCR_TVM)) {
1906 trace_kvm_set_way_flush(*vcpu_pc(vcpu),
1907 vcpu_has_cache_enabled(vcpu));
1908 stage2_flush_vm(vcpu->kvm);
1909 vcpu_set_hcr(vcpu, hcr | HCR_TVM);
1910 }
1911}
1912
1913void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled)
1914{
1915 bool now_enabled = vcpu_has_cache_enabled(vcpu);
1916
1917 /*
1918 * If switching the MMU+caches on, need to invalidate the caches.
1919 * If switching it off, need to clean the caches.
1920 * Clean + invalidate does the trick always.
1921 */
1922 if (now_enabled != was_enabled)
1923 stage2_flush_vm(vcpu->kvm);
1924
1925 /* Caches are now on, stop trapping VM ops (until a S/W op) */
1926 if (now_enabled)
1927 vcpu_set_hcr(vcpu, vcpu_get_hcr(vcpu) & ~HCR_TVM);
1928
1929 trace_kvm_toggle_cache(*vcpu_pc(vcpu), was_enabled, now_enabled);
1930}