mmu.c 19.6 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17
/*
 * Copyright (C) 2012 - Virtual Open Systems and Columbia University
 * Author: Christoffer Dall <c.dall@virtualopensystems.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License, version 2, as
 * published by the Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 */
18 19 20 21

#include <linux/mman.h>
#include <linux/kvm_host.h>
#include <linux/io.h>
C
Christoffer Dall 已提交
22
#include <trace/events/kvm.h>
23 24
#include <asm/idmap.h>
#include <asm/pgalloc.h>
25
#include <asm/cacheflush.h>
26 27
#include <asm/kvm_arm.h>
#include <asm/kvm_mmu.h>
C
Christoffer Dall 已提交
28
#include <asm/kvm_mmio.h>
29
#include <asm/kvm_asm.h>
30
#include <asm/kvm_emulate.h>
31
#include <asm/mach/map.h>
32 33 34
#include <trace/events/kvm.h>

#include "trace.h"
35 36 37 38 39

extern char  __hyp_idmap_text_start[], __hyp_idmap_text_end[];

static DEFINE_MUTEX(kvm_hyp_pgd_mutex);

40 41 42 43 44
static void kvm_tlb_flush_vmid(struct kvm *kvm)
{
	kvm_call_hyp(__kvm_tlb_flush_vmid, kvm);
}

45 46 47 48 49 50 51 52 53 54
static void kvm_set_pte(pte_t *pte, pte_t new_pte)
{
	pte_val(*pte) = new_pte;
	/*
	 * flush_pmd_entry just takes a void pointer and cleans the necessary
	 * cache entries, so we can reuse the function for ptes.
	 */
	flush_pmd_entry(pte);
}

55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86
static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
				  int min, int max)
{
	void *page;

	BUG_ON(max > KVM_NR_MEM_OBJS);
	if (cache->nobjs >= min)
		return 0;
	while (cache->nobjs < max) {
		page = (void *)__get_free_page(PGALLOC_GFP);
		if (!page)
			return -ENOMEM;
		cache->objects[cache->nobjs++] = page;
	}
	return 0;
}

static void mmu_free_memory_cache(struct kvm_mmu_memory_cache *mc)
{
	while (mc->nobjs)
		free_page((unsigned long)mc->objects[--mc->nobjs]);
}

static void *mmu_memory_cache_alloc(struct kvm_mmu_memory_cache *mc)
{
	void *p;

	BUG_ON(!mc || !mc->nobjs);
	p = mc->objects[--mc->nobjs];
	return p;
}

87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264
static void free_ptes(pmd_t *pmd, unsigned long addr)
{
	pte_t *pte;
	unsigned int i;

	for (i = 0; i < PTRS_PER_PMD; i++, addr += PMD_SIZE) {
		if (!pmd_none(*pmd) && pmd_table(*pmd)) {
			pte = pte_offset_kernel(pmd, addr);
			pte_free_kernel(NULL, pte);
		}
		pmd++;
	}
}

/**
 * free_hyp_pmds - free a Hyp-mode level-2 tables and child level-3 tables
 *
 * Assumes this is a page table used strictly in Hyp-mode and therefore contains
 * only mappings in the kernel memory area, which is above PAGE_OFFSET.
 */
void free_hyp_pmds(void)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	unsigned long addr;

	mutex_lock(&kvm_hyp_pgd_mutex);
	for (addr = PAGE_OFFSET; addr != 0; addr += PGDIR_SIZE) {
		pgd = hyp_pgd + pgd_index(addr);
		pud = pud_offset(pgd, addr);

		if (pud_none(*pud))
			continue;
		BUG_ON(pud_bad(*pud));

		pmd = pmd_offset(pud, addr);
		free_ptes(pmd, addr);
		pmd_free(NULL, pmd);
		pud_clear(pud);
	}
	mutex_unlock(&kvm_hyp_pgd_mutex);
}

static void create_hyp_pte_mappings(pmd_t *pmd, unsigned long start,
				    unsigned long end)
{
	pte_t *pte;
	unsigned long addr;
	struct page *page;

	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
		pte = pte_offset_kernel(pmd, addr);
		BUG_ON(!virt_addr_valid(addr));
		page = virt_to_page(addr);
		kvm_set_pte(pte, mk_pte(page, PAGE_HYP));
	}
}

static void create_hyp_io_pte_mappings(pmd_t *pmd, unsigned long start,
				       unsigned long end,
				       unsigned long *pfn_base)
{
	pte_t *pte;
	unsigned long addr;

	for (addr = start & PAGE_MASK; addr < end; addr += PAGE_SIZE) {
		pte = pte_offset_kernel(pmd, addr);
		BUG_ON(pfn_valid(*pfn_base));
		kvm_set_pte(pte, pfn_pte(*pfn_base, PAGE_HYP_DEVICE));
		(*pfn_base)++;
	}
}

static int create_hyp_pmd_mappings(pud_t *pud, unsigned long start,
				   unsigned long end, unsigned long *pfn_base)
{
	pmd_t *pmd;
	pte_t *pte;
	unsigned long addr, next;

	for (addr = start; addr < end; addr = next) {
		pmd = pmd_offset(pud, addr);

		BUG_ON(pmd_sect(*pmd));

		if (pmd_none(*pmd)) {
			pte = pte_alloc_one_kernel(NULL, addr);
			if (!pte) {
				kvm_err("Cannot allocate Hyp pte\n");
				return -ENOMEM;
			}
			pmd_populate_kernel(NULL, pmd, pte);
		}

		next = pmd_addr_end(addr, end);

		/*
		 * If pfn_base is NULL, we map kernel pages into HYP with the
		 * virtual address. Otherwise, this is considered an I/O
		 * mapping and we map the physical region starting at
		 * *pfn_base to [start, end[.
		 */
		if (!pfn_base)
			create_hyp_pte_mappings(pmd, addr, next);
		else
			create_hyp_io_pte_mappings(pmd, addr, next, pfn_base);
	}

	return 0;
}

static int __create_hyp_mappings(void *from, void *to, unsigned long *pfn_base)
{
	unsigned long start = (unsigned long)from;
	unsigned long end = (unsigned long)to;
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	unsigned long addr, next;
	int err = 0;

	BUG_ON(start > end);
	if (start < PAGE_OFFSET)
		return -EINVAL;

	mutex_lock(&kvm_hyp_pgd_mutex);
	for (addr = start; addr < end; addr = next) {
		pgd = hyp_pgd + pgd_index(addr);
		pud = pud_offset(pgd, addr);

		if (pud_none_or_clear_bad(pud)) {
			pmd = pmd_alloc_one(NULL, addr);
			if (!pmd) {
				kvm_err("Cannot allocate Hyp pmd\n");
				err = -ENOMEM;
				goto out;
			}
			pud_populate(NULL, pud, pmd);
		}

		next = pgd_addr_end(addr, end);
		err = create_hyp_pmd_mappings(pud, addr, next, pfn_base);
		if (err)
			goto out;
	}
out:
	mutex_unlock(&kvm_hyp_pgd_mutex);
	return err;
}

/**
 * create_hyp_mappings - map a kernel virtual address range in Hyp mode
 * @from:	The virtual kernel start address of the range
 * @to:		The virtual kernel end address of the range (exclusive)
 *
 * The same virtual address as the kernel virtual address is also used in
 * Hyp-mode mapping to the same underlying physical pages.
 *
 * Note: Wrapping around zero in the "to" address is not supported.
 */
int create_hyp_mappings(void *from, void *to)
{
	return __create_hyp_mappings(from, to, NULL);
}

/**
 * create_hyp_io_mappings - map a physical IO range in Hyp mode
 * @from:	The virtual HYP start address of the range
 * @to:		The virtual HYP end address of the range (exclusive)
 * @addr:	The physical start address which gets mapped
 */
int create_hyp_io_mappings(void *from, void *to, phys_addr_t addr)
{
	unsigned long pfn = __phys_to_pfn(addr);
	return __create_hyp_mappings(from, to, &pfn);
}

265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494
/**
 * kvm_alloc_stage2_pgd - allocate level-1 table for stage-2 translation.
 * @kvm:	The KVM struct pointer for the VM.
 *
 * Allocates the 1st level table only of size defined by S2_PGD_ORDER (can
 * support either full 40-bit input addresses or limited to 32-bit input
 * addresses). Clears the allocated pages.
 *
 * Note we don't need locking here as this is only called when the VM is
 * created, which can only be done once.
 */
int kvm_alloc_stage2_pgd(struct kvm *kvm)
{
	pgd_t *pgd;

	if (kvm->arch.pgd != NULL) {
		kvm_err("kvm_arch already initialized?\n");
		return -EINVAL;
	}

	pgd = (pgd_t *)__get_free_pages(GFP_KERNEL, S2_PGD_ORDER);
	if (!pgd)
		return -ENOMEM;

	/* stage-2 pgd must be aligned to its size */
	VM_BUG_ON((unsigned long)pgd & (S2_PGD_SIZE - 1));

	memset(pgd, 0, PTRS_PER_S2_PGD * sizeof(pgd_t));
	clean_dcache_area(pgd, PTRS_PER_S2_PGD * sizeof(pgd_t));
	kvm->arch.pgd = pgd;

	return 0;
}

static void clear_pud_entry(pud_t *pud)
{
	pmd_t *pmd_table = pmd_offset(pud, 0);
	pud_clear(pud);
	pmd_free(NULL, pmd_table);
	put_page(virt_to_page(pud));
}

static void clear_pmd_entry(pmd_t *pmd)
{
	pte_t *pte_table = pte_offset_kernel(pmd, 0);
	pmd_clear(pmd);
	pte_free_kernel(NULL, pte_table);
	put_page(virt_to_page(pmd));
}

static bool pmd_empty(pmd_t *pmd)
{
	struct page *pmd_page = virt_to_page(pmd);
	return page_count(pmd_page) == 1;
}

static void clear_pte_entry(pte_t *pte)
{
	if (pte_present(*pte)) {
		kvm_set_pte(pte, __pte(0));
		put_page(virt_to_page(pte));
	}
}

static bool pte_empty(pte_t *pte)
{
	struct page *pte_page = virt_to_page(pte);
	return page_count(pte_page) == 1;
}

/**
 * unmap_stage2_range -- Clear stage2 page table entries to unmap a range
 * @kvm:   The VM pointer
 * @start: The intermediate physical base address of the range to unmap
 * @size:  The size of the area to unmap
 *
 * Clear a range of stage-2 mappings, lowering the various ref-counts.  Must
 * be called while holding mmu_lock (unless for freeing the stage2 pgd before
 * destroying the VM), otherwise another faulting VCPU may come in and mess
 * with things behind our backs.
 */
static void unmap_stage2_range(struct kvm *kvm, phys_addr_t start, u64 size)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte;
	phys_addr_t addr = start, end = start + size;
	u64 range;

	while (addr < end) {
		pgd = kvm->arch.pgd + pgd_index(addr);
		pud = pud_offset(pgd, addr);
		if (pud_none(*pud)) {
			addr += PUD_SIZE;
			continue;
		}

		pmd = pmd_offset(pud, addr);
		if (pmd_none(*pmd)) {
			addr += PMD_SIZE;
			continue;
		}

		pte = pte_offset_kernel(pmd, addr);
		clear_pte_entry(pte);
		range = PAGE_SIZE;

		/* If we emptied the pte, walk back up the ladder */
		if (pte_empty(pte)) {
			clear_pmd_entry(pmd);
			range = PMD_SIZE;
			if (pmd_empty(pmd)) {
				clear_pud_entry(pud);
				range = PUD_SIZE;
			}
		}

		addr += range;
	}
}

/**
 * kvm_free_stage2_pgd - free all stage-2 tables
 * @kvm:	The KVM struct pointer for the VM.
 *
 * Walks the level-1 page table pointed to by kvm->arch.pgd and frees all
 * underlying level-2 and level-3 tables before freeing the actual level-1 table
 * and setting the struct pointer to NULL.
 *
 * Note we don't need locking here as this is only called when the VM is
 * destroyed, which can only be done once.
 */
void kvm_free_stage2_pgd(struct kvm *kvm)
{
	if (kvm->arch.pgd == NULL)
		return;

	unmap_stage2_range(kvm, 0, KVM_PHYS_SIZE);
	free_pages((unsigned long)kvm->arch.pgd, S2_PGD_ORDER);
	kvm->arch.pgd = NULL;
}


static int stage2_set_pte(struct kvm *kvm, struct kvm_mmu_memory_cache *cache,
			  phys_addr_t addr, const pte_t *new_pte, bool iomap)
{
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte, old_pte;

	/* Create 2nd stage page table mapping - Level 1 */
	pgd = kvm->arch.pgd + pgd_index(addr);
	pud = pud_offset(pgd, addr);
	if (pud_none(*pud)) {
		if (!cache)
			return 0; /* ignore calls from kvm_set_spte_hva */
		pmd = mmu_memory_cache_alloc(cache);
		pud_populate(NULL, pud, pmd);
		pmd += pmd_index(addr);
		get_page(virt_to_page(pud));
	} else
		pmd = pmd_offset(pud, addr);

	/* Create 2nd stage page table mapping - Level 2 */
	if (pmd_none(*pmd)) {
		if (!cache)
			return 0; /* ignore calls from kvm_set_spte_hva */
		pte = mmu_memory_cache_alloc(cache);
		clean_pte_table(pte);
		pmd_populate_kernel(NULL, pmd, pte);
		pte += pte_index(addr);
		get_page(virt_to_page(pmd));
	} else
		pte = pte_offset_kernel(pmd, addr);

	if (iomap && pte_present(*pte))
		return -EFAULT;

	/* Create 2nd stage page table mapping - Level 3 */
	old_pte = *pte;
	kvm_set_pte(pte, *new_pte);
	if (pte_present(old_pte))
		kvm_tlb_flush_vmid(kvm);
	else
		get_page(virt_to_page(pte));

	return 0;
}

/**
 * kvm_phys_addr_ioremap - map a device range to guest IPA
 *
 * @kvm:	The KVM pointer
 * @guest_ipa:	The IPA at which to insert the mapping
 * @pa:		The physical address of the device
 * @size:	The size of the mapping
 */
int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
			  phys_addr_t pa, unsigned long size)
{
	phys_addr_t addr, end;
	int ret = 0;
	unsigned long pfn;
	struct kvm_mmu_memory_cache cache = { 0, };

	end = (guest_ipa + size + PAGE_SIZE - 1) & PAGE_MASK;
	pfn = __phys_to_pfn(pa);

	for (addr = guest_ipa; addr < end; addr += PAGE_SIZE) {
		pte_t pte = pfn_pte(pfn, PAGE_S2_DEVICE | L_PTE_S2_RDWR);

		ret = mmu_topup_memory_cache(&cache, 2, 2);
		if (ret)
			goto out;
		spin_lock(&kvm->mmu_lock);
		ret = stage2_set_pte(kvm, &cache, addr, &pte, true);
		spin_unlock(&kvm->mmu_lock);
		if (ret)
			goto out;

		pfn++;
	}

out:
	mmu_free_memory_cache(&cache);
	return ret;
}

495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 542 543 544 545 546 547 548 549 550 551 552 553 554 555 556 557 558 559 560 561 562 563 564 565 566 567 568 569 570 571 572 573 574 575 576 577 578 579 580 581 582 583 584 585
static void coherent_icache_guest_page(struct kvm *kvm, gfn_t gfn)
{
	/*
	 * If we are going to insert an instruction page and the icache is
	 * either VIPT or PIPT, there is a potential problem where the host
	 * (or another VM) may have used the same page as this guest, and we
	 * read incorrect data from the icache.  If we're using a PIPT cache,
	 * we can invalidate just that page, but if we are using a VIPT cache
	 * we need to invalidate the entire icache - damn shame - as written
	 * in the ARM ARM (DDI 0406C.b - Page B3-1393).
	 *
	 * VIVT caches are tagged using both the ASID and the VMID and doesn't
	 * need any kind of flushing (DDI 0406C.b - Page B3-1392).
	 */
	if (icache_is_pipt()) {
		unsigned long hva = gfn_to_hva(kvm, gfn);
		__cpuc_coherent_user_range(hva, hva + PAGE_SIZE);
	} else if (!icache_is_vivt_asid_tagged()) {
		/* any kind of VIPT cache */
		__flush_icache_all();
	}
}

static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
			  gfn_t gfn, struct kvm_memory_slot *memslot,
			  unsigned long fault_status)
{
	pte_t new_pte;
	pfn_t pfn;
	int ret;
	bool write_fault, writable;
	unsigned long mmu_seq;
	struct kvm_mmu_memory_cache *memcache = &vcpu->arch.mmu_page_cache;

	write_fault = kvm_is_write_fault(vcpu->arch.hsr);
	if (fault_status == FSC_PERM && !write_fault) {
		kvm_err("Unexpected L2 read permission error\n");
		return -EFAULT;
	}

	/* We need minimum second+third level pages */
	ret = mmu_topup_memory_cache(memcache, 2, KVM_NR_MEM_OBJS);
	if (ret)
		return ret;

	mmu_seq = vcpu->kvm->mmu_notifier_seq;
	/*
	 * Ensure the read of mmu_notifier_seq happens before we call
	 * gfn_to_pfn_prot (which calls get_user_pages), so that we don't risk
	 * the page we just got a reference to gets unmapped before we have a
	 * chance to grab the mmu_lock, which ensure that if the page gets
	 * unmapped afterwards, the call to kvm_unmap_hva will take it away
	 * from us again properly. This smp_rmb() interacts with the smp_wmb()
	 * in kvm_mmu_notifier_invalidate_<page|range_end>.
	 */
	smp_rmb();

	pfn = gfn_to_pfn_prot(vcpu->kvm, gfn, write_fault, &writable);
	if (is_error_pfn(pfn))
		return -EFAULT;

	new_pte = pfn_pte(pfn, PAGE_S2);
	coherent_icache_guest_page(vcpu->kvm, gfn);

	spin_lock(&vcpu->kvm->mmu_lock);
	if (mmu_notifier_retry(vcpu->kvm, mmu_seq))
		goto out_unlock;
	if (writable) {
		pte_val(new_pte) |= L_PTE_S2_RDWR;
		kvm_set_pfn_dirty(pfn);
	}
	stage2_set_pte(vcpu->kvm, memcache, fault_ipa, &new_pte, false);

out_unlock:
	spin_unlock(&vcpu->kvm->mmu_lock);
	kvm_release_pfn_clean(pfn);
	return 0;
}

/**
 * kvm_handle_guest_abort - handles all 2nd stage aborts
 * @vcpu:	the VCPU pointer
 * @run:	the kvm_run structure
 *
 * Any abort that gets to the host is almost guaranteed to be caused by a
 * missing second stage translation table entry, which can mean that either the
 * guest simply needs more memory and we must allocate an appropriate page or it
 * can mean that the guest tried to access I/O memory, which is emulated by user
 * space. The distinction is based on the IPA causing the fault and whether this
 * memory region has been registered as standard RAM by user space.
 */
586 587
int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run)
{
588 589 590 591 592 593 594 595 596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 613 614 615 616 617 618 619 620 621 622 623 624 625 626 627 628
	unsigned long hsr_ec;
	unsigned long fault_status;
	phys_addr_t fault_ipa;
	struct kvm_memory_slot *memslot;
	bool is_iabt;
	gfn_t gfn;
	int ret, idx;

	hsr_ec = vcpu->arch.hsr >> HSR_EC_SHIFT;
	is_iabt = (hsr_ec == HSR_EC_IABT);
	fault_ipa = ((phys_addr_t)vcpu->arch.hpfar & HPFAR_MASK) << 8;

	trace_kvm_guest_fault(*vcpu_pc(vcpu), vcpu->arch.hsr,
			      vcpu->arch.hxfar, fault_ipa);

	/* Check the stage-2 fault is trans. fault or write fault */
	fault_status = (vcpu->arch.hsr & HSR_FSC_TYPE);
	if (fault_status != FSC_FAULT && fault_status != FSC_PERM) {
		kvm_err("Unsupported fault status: EC=%#lx DFCS=%#lx\n",
			hsr_ec, fault_status);
		return -EFAULT;
	}

	idx = srcu_read_lock(&vcpu->kvm->srcu);

	gfn = fault_ipa >> PAGE_SHIFT;
	if (!kvm_is_visible_gfn(vcpu->kvm, gfn)) {
		if (is_iabt) {
			/* Prefetch Abort on I/O address */
			kvm_inject_pabt(vcpu, vcpu->arch.hxfar);
			ret = 1;
			goto out_unlock;
		}

		if (fault_status != FSC_FAULT) {
			kvm_err("Unsupported fault status on io memory: %#lx\n",
				fault_status);
			ret = -EFAULT;
			goto out_unlock;
		}

C
Christoffer Dall 已提交
629 630 631
		/* Adjust page offset */
		fault_ipa |= vcpu->arch.hxfar & ~PAGE_MASK;
		ret = io_mem_abort(vcpu, run, fault_ipa);
632 633 634 635 636 637 638 639 640 641 642
		goto out_unlock;
	}

	memslot = gfn_to_memslot(vcpu->kvm, gfn);

	ret = user_mem_abort(vcpu, fault_ipa, gfn, memslot, fault_status);
	if (ret == 0)
		ret = 1;
out_unlock:
	srcu_read_unlock(&vcpu->kvm->srcu, idx);
	return ret;
643 644
}

645 646 647 648 649 650 651 652 653 654 655 656 657 658 659 660 661 662 663 664 665 666 667 668 669 670 671 672 673 674 675 676 677 678 679 680 681 682 683 684 685 686 687 688 689 690 691 692 693 694 695 696 697 698 699 700 701 702 703 704 705 706 707 708 709 710 711 712 713 714 715 716 717 718 719 720 721 722 723 724 725 726 727 728 729 730 731 732 733 734 735 736
static void handle_hva_to_gpa(struct kvm *kvm,
			      unsigned long start,
			      unsigned long end,
			      void (*handler)(struct kvm *kvm,
					      gpa_t gpa, void *data),
			      void *data)
{
	struct kvm_memslots *slots;
	struct kvm_memory_slot *memslot;

	slots = kvm_memslots(kvm);

	/* we only care about the pages that the guest sees */
	kvm_for_each_memslot(memslot, slots) {
		unsigned long hva_start, hva_end;
		gfn_t gfn, gfn_end;

		hva_start = max(start, memslot->userspace_addr);
		hva_end = min(end, memslot->userspace_addr +
					(memslot->npages << PAGE_SHIFT));
		if (hva_start >= hva_end)
			continue;

		/*
		 * {gfn(page) | page intersects with [hva_start, hva_end)} =
		 * {gfn_start, gfn_start+1, ..., gfn_end-1}.
		 */
		gfn = hva_to_gfn_memslot(hva_start, memslot);
		gfn_end = hva_to_gfn_memslot(hva_end + PAGE_SIZE - 1, memslot);

		for (; gfn < gfn_end; ++gfn) {
			gpa_t gpa = gfn << PAGE_SHIFT;
			handler(kvm, gpa, data);
		}
	}
}

static void kvm_unmap_hva_handler(struct kvm *kvm, gpa_t gpa, void *data)
{
	unmap_stage2_range(kvm, gpa, PAGE_SIZE);
	kvm_tlb_flush_vmid(kvm);
}

int kvm_unmap_hva(struct kvm *kvm, unsigned long hva)
{
	unsigned long end = hva + PAGE_SIZE;

	if (!kvm->arch.pgd)
		return 0;

	trace_kvm_unmap_hva(hva);
	handle_hva_to_gpa(kvm, hva, end, &kvm_unmap_hva_handler, NULL);
	return 0;
}

int kvm_unmap_hva_range(struct kvm *kvm,
			unsigned long start, unsigned long end)
{
	if (!kvm->arch.pgd)
		return 0;

	trace_kvm_unmap_hva_range(start, end);
	handle_hva_to_gpa(kvm, start, end, &kvm_unmap_hva_handler, NULL);
	return 0;
}

static void kvm_set_spte_handler(struct kvm *kvm, gpa_t gpa, void *data)
{
	pte_t *pte = (pte_t *)data;

	stage2_set_pte(kvm, NULL, gpa, pte, false);
}


void kvm_set_spte_hva(struct kvm *kvm, unsigned long hva, pte_t pte)
{
	unsigned long end = hva + PAGE_SIZE;
	pte_t stage2_pte;

	if (!kvm->arch.pgd)
		return;

	trace_kvm_set_spte_hva(hva);
	stage2_pte = pfn_pte(pte_pfn(pte), PAGE_S2);
	handle_hva_to_gpa(kvm, hva, end, &kvm_set_spte_handler, &stage2_pte);
}

void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu)
{
	mmu_free_memory_cache(&vcpu->arch.mmu_page_cache);
}

737 738 739 740 741 742 743 744
phys_addr_t kvm_mmu_get_httbr(void)
{
	VM_BUG_ON(!virt_addr_valid(hyp_pgd));
	return virt_to_phys(hyp_pgd);
}

int kvm_mmu_init(void)
{
745 746 747 748 749 750
	if (!hyp_pgd) {
		kvm_err("Hyp mode PGD not allocated\n");
		return -ENOMEM;
	}

	return 0;
751 752 753 754 755 756 757 758 759 760 761 762 763 764 765 766 767 768 769 770 771 772 773 774 775 776 777 778 779 780 781 782
}

/**
 * kvm_clear_idmap - remove all idmaps from the hyp pgd
 *
 * Free the underlying pmds for all pgds in range and clear the pgds (but
 * don't free them) afterwards.
 */
void kvm_clear_hyp_idmap(void)
{
	unsigned long addr, end;
	unsigned long next;
	pgd_t *pgd = hyp_pgd;
	pud_t *pud;
	pmd_t *pmd;

	addr = virt_to_phys(__hyp_idmap_text_start);
	end = virt_to_phys(__hyp_idmap_text_end);

	pgd += pgd_index(addr);
	do {
		next = pgd_addr_end(addr, end);
		if (pgd_none_or_clear_bad(pgd))
			continue;
		pud = pud_offset(pgd, addr);
		pmd = pmd_offset(pud, addr);

		pud_clear(pud);
		clean_pmd_entry(pmd);
		pmd_free(NULL, (pmd_t *)((unsigned long)pmd & PAGE_MASK));
	} while (pgd++, addr = next, addr < end);
}