314 lines
9.0 KiB
C
314 lines
9.0 KiB
C
/*
|
|
* Copyright (C) 2012,2013 - ARM Ltd
|
|
* Author: Marc Zyngier <marc.zyngier@arm.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, see <http://www.gnu.org/licenses/>.
|
|
*/
|
|
|
|
#ifndef __ARM64_KVM_MMU_H__
|
|
#define __ARM64_KVM_MMU_H__
|
|
|
|
#include <asm/page.h>
|
|
#include <asm/memory.h>
|
|
#include <asm/cpufeature.h>
|
|
|
|
/*
|
|
* As ARMv8.0 only has the TTBR0_EL2 register, we cannot express
|
|
* "negative" addresses. This makes it impossible to directly share
|
|
* mappings with the kernel.
|
|
*
|
|
* Instead, give the HYP mode its own VA region at a fixed offset from
|
|
* the kernel by just masking the top bits (which are all ones for a
|
|
* kernel address). We need to find out how many bits to mask.
|
|
*
|
|
* We want to build a set of page tables that cover both parts of the
|
|
* idmap (the trampoline page used to initialize EL2), and our normal
|
|
* runtime VA space, at the same time.
|
|
*
|
|
* Given that the kernel uses VA_BITS for its entire address space,
|
|
* and that half of that space (VA_BITS - 1) is used for the linear
|
|
* mapping, we can also limit the EL2 space to (VA_BITS - 1).
|
|
*
|
|
* The main question is "Within the VA_BITS space, does EL2 use the
|
|
* top or the bottom half of that space to shadow the kernel's linear
|
|
* mapping?". As we need to idmap the trampoline page, this is
|
|
* determined by the range in which this page lives.
|
|
*
|
|
* If the page is in the bottom half, we have to use the top half. If
|
|
* the page is in the top half, we have to use the bottom half:
|
|
*
|
|
* T = __pa_symbol(__hyp_idmap_text_start)
|
|
* if (T & BIT(VA_BITS - 1))
|
|
* HYP_VA_MIN = 0 //idmap in upper half
|
|
* else
|
|
* HYP_VA_MIN = 1 << (VA_BITS - 1)
|
|
* HYP_VA_MAX = HYP_VA_MIN + (1 << (VA_BITS - 1)) - 1
|
|
*
|
|
* This of course assumes that the trampoline page exists within the
|
|
* VA_BITS range. If it doesn't, then it means we're in the odd case
|
|
* where the kernel idmap (as well as HYP) uses more levels than the
|
|
* kernel runtime page tables (as seen when the kernel is configured
|
|
* for 4k pages, 39bits VA, and yet memory lives just above that
|
|
* limit, forcing the idmap to use 4 levels of page tables while the
|
|
* kernel itself only uses 3). In this particular case, it doesn't
|
|
* matter which side of VA_BITS we use, as we're guaranteed not to
|
|
* conflict with anything.
|
|
*
|
|
* When using VHE, there are no separate hyp mappings and all KVM
|
|
* functionality is already mapped as part of the main kernel
|
|
* mappings, and none of this applies in that case.
|
|
*/
|
|
|
|
#define HYP_PAGE_OFFSET_HIGH_MASK ((UL(1) << VA_BITS) - 1)
|
|
#define HYP_PAGE_OFFSET_LOW_MASK ((UL(1) << (VA_BITS - 1)) - 1)
|
|
|
|
#ifdef __ASSEMBLY__
|
|
|
|
#include <asm/alternative.h>
|
|
#include <asm/cpufeature.h>
|
|
|
|
/*
|
|
* Convert a kernel VA into a HYP VA.
|
|
* reg: VA to be converted.
|
|
*
|
|
* This generates the following sequences:
|
|
* - High mask:
|
|
* and x0, x0, #HYP_PAGE_OFFSET_HIGH_MASK
|
|
* nop
|
|
* - Low mask:
|
|
* and x0, x0, #HYP_PAGE_OFFSET_HIGH_MASK
|
|
* and x0, x0, #HYP_PAGE_OFFSET_LOW_MASK
|
|
* - VHE:
|
|
* nop
|
|
* nop
|
|
*
|
|
* The "low mask" version works because the mask is a strict subset of
|
|
* the "high mask", hence performing the first mask for nothing.
|
|
* Should be completely invisible on any viable CPU.
|
|
*/
|
|
.macro kern_hyp_va reg
|
|
alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
|
|
and \reg, \reg, #HYP_PAGE_OFFSET_HIGH_MASK
|
|
alternative_else_nop_endif
|
|
alternative_if ARM64_HYP_OFFSET_LOW
|
|
and \reg, \reg, #HYP_PAGE_OFFSET_LOW_MASK
|
|
alternative_else_nop_endif
|
|
.endm
|
|
|
|
#else
|
|
|
|
#include <asm/pgalloc.h>
|
|
#include <asm/cache.h>
|
|
#include <asm/cacheflush.h>
|
|
#include <asm/mmu_context.h>
|
|
#include <asm/pgtable.h>
|
|
|
|
static inline unsigned long __kern_hyp_va(unsigned long v)
|
|
{
|
|
asm volatile(ALTERNATIVE("and %0, %0, %1",
|
|
"nop",
|
|
ARM64_HAS_VIRT_HOST_EXTN)
|
|
: "+r" (v)
|
|
: "i" (HYP_PAGE_OFFSET_HIGH_MASK));
|
|
asm volatile(ALTERNATIVE("nop",
|
|
"and %0, %0, %1",
|
|
ARM64_HYP_OFFSET_LOW)
|
|
: "+r" (v)
|
|
: "i" (HYP_PAGE_OFFSET_LOW_MASK));
|
|
return v;
|
|
}
|
|
|
|
#define kern_hyp_va(v) ((typeof(v))(__kern_hyp_va((unsigned long)(v))))
|
|
|
|
/*
|
|
* We currently only support a 40bit IPA.
|
|
*/
|
|
#define KVM_PHYS_SHIFT (40)
|
|
#define KVM_PHYS_SIZE (1UL << KVM_PHYS_SHIFT)
|
|
#define KVM_PHYS_MASK (KVM_PHYS_SIZE - 1UL)
|
|
|
|
#include <asm/stage2_pgtable.h>
|
|
|
|
int create_hyp_mappings(void *from, void *to, pgprot_t prot);
|
|
int create_hyp_io_mappings(void *from, void *to, phys_addr_t);
|
|
void free_hyp_pgds(void);
|
|
|
|
void stage2_unmap_vm(struct kvm *kvm);
|
|
int kvm_alloc_stage2_pgd(struct kvm *kvm);
|
|
void kvm_free_stage2_pgd(struct kvm *kvm);
|
|
int kvm_phys_addr_ioremap(struct kvm *kvm, phys_addr_t guest_ipa,
|
|
phys_addr_t pa, unsigned long size, bool writable);
|
|
|
|
int kvm_handle_guest_abort(struct kvm_vcpu *vcpu, struct kvm_run *run);
|
|
|
|
void kvm_mmu_free_memory_caches(struct kvm_vcpu *vcpu);
|
|
|
|
phys_addr_t kvm_mmu_get_httbr(void);
|
|
phys_addr_t kvm_get_idmap_vector(void);
|
|
int kvm_mmu_init(void);
|
|
void kvm_clear_hyp_idmap(void);
|
|
|
|
#define kvm_set_pte(ptep, pte) set_pte(ptep, pte)
|
|
#define kvm_set_pmd(pmdp, pmd) set_pmd(pmdp, pmd)
|
|
|
|
static inline pte_t kvm_s2pte_mkwrite(pte_t pte)
|
|
{
|
|
pte_val(pte) |= PTE_S2_RDWR;
|
|
return pte;
|
|
}
|
|
|
|
static inline pmd_t kvm_s2pmd_mkwrite(pmd_t pmd)
|
|
{
|
|
pmd_val(pmd) |= PMD_S2_RDWR;
|
|
return pmd;
|
|
}
|
|
|
|
static inline void kvm_set_s2pte_readonly(pte_t *pte)
|
|
{
|
|
pteval_t old_pteval, pteval;
|
|
|
|
pteval = READ_ONCE(pte_val(*pte));
|
|
do {
|
|
old_pteval = pteval;
|
|
pteval &= ~PTE_S2_RDWR;
|
|
pteval |= PTE_S2_RDONLY;
|
|
pteval = cmpxchg_relaxed(&pte_val(*pte), old_pteval, pteval);
|
|
} while (pteval != old_pteval);
|
|
}
|
|
|
|
static inline bool kvm_s2pte_readonly(pte_t *pte)
|
|
{
|
|
return (pte_val(*pte) & PTE_S2_RDWR) == PTE_S2_RDONLY;
|
|
}
|
|
|
|
static inline void kvm_set_s2pmd_readonly(pmd_t *pmd)
|
|
{
|
|
kvm_set_s2pte_readonly((pte_t *)pmd);
|
|
}
|
|
|
|
static inline bool kvm_s2pmd_readonly(pmd_t *pmd)
|
|
{
|
|
return kvm_s2pte_readonly((pte_t *)pmd);
|
|
}
|
|
|
|
static inline bool kvm_page_empty(void *ptr)
|
|
{
|
|
struct page *ptr_page = virt_to_page(ptr);
|
|
return page_count(ptr_page) == 1;
|
|
}
|
|
|
|
#define hyp_pte_table_empty(ptep) kvm_page_empty(ptep)
|
|
|
|
#ifdef __PAGETABLE_PMD_FOLDED
|
|
#define hyp_pmd_table_empty(pmdp) (0)
|
|
#else
|
|
#define hyp_pmd_table_empty(pmdp) kvm_page_empty(pmdp)
|
|
#endif
|
|
|
|
#ifdef __PAGETABLE_PUD_FOLDED
|
|
#define hyp_pud_table_empty(pudp) (0)
|
|
#else
|
|
#define hyp_pud_table_empty(pudp) kvm_page_empty(pudp)
|
|
#endif
|
|
|
|
struct kvm;
|
|
|
|
#define kvm_flush_dcache_to_poc(a,l) __flush_dcache_area((a), (l))
|
|
|
|
static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu)
|
|
{
|
|
return (vcpu_sys_reg(vcpu, SCTLR_EL1) & 0b101) == 0b101;
|
|
}
|
|
|
|
static inline void __coherent_cache_guest_page(struct kvm_vcpu *vcpu,
|
|
kvm_pfn_t pfn,
|
|
unsigned long size)
|
|
{
|
|
void *va = page_address(pfn_to_page(pfn));
|
|
|
|
kvm_flush_dcache_to_poc(va, size);
|
|
|
|
if (icache_is_aliasing()) {
|
|
/* any kind of VIPT cache */
|
|
__flush_icache_all();
|
|
} else if (is_kernel_in_hyp_mode() || !icache_is_vpipt()) {
|
|
/* PIPT or VPIPT at EL2 (see comment in __kvm_tlb_flush_vmid_ipa) */
|
|
flush_icache_range((unsigned long)va,
|
|
(unsigned long)va + size);
|
|
}
|
|
}
|
|
|
|
static inline void __kvm_flush_dcache_pte(pte_t pte)
|
|
{
|
|
struct page *page = pte_page(pte);
|
|
kvm_flush_dcache_to_poc(page_address(page), PAGE_SIZE);
|
|
}
|
|
|
|
static inline void __kvm_flush_dcache_pmd(pmd_t pmd)
|
|
{
|
|
struct page *page = pmd_page(pmd);
|
|
kvm_flush_dcache_to_poc(page_address(page), PMD_SIZE);
|
|
}
|
|
|
|
static inline void __kvm_flush_dcache_pud(pud_t pud)
|
|
{
|
|
struct page *page = pud_page(pud);
|
|
kvm_flush_dcache_to_poc(page_address(page), PUD_SIZE);
|
|
}
|
|
|
|
#define kvm_virt_to_phys(x) __pa_symbol(x)
|
|
|
|
void kvm_set_way_flush(struct kvm_vcpu *vcpu);
|
|
void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled);
|
|
|
|
static inline bool __kvm_cpu_uses_extended_idmap(void)
|
|
{
|
|
return __cpu_uses_extended_idmap();
|
|
}
|
|
|
|
static inline void __kvm_extend_hypmap(pgd_t *boot_hyp_pgd,
|
|
pgd_t *hyp_pgd,
|
|
pgd_t *merged_hyp_pgd,
|
|
unsigned long hyp_idmap_start)
|
|
{
|
|
int idmap_idx;
|
|
|
|
/*
|
|
* Use the first entry to access the HYP mappings. It is
|
|
* guaranteed to be free, otherwise we wouldn't use an
|
|
* extended idmap.
|
|
*/
|
|
VM_BUG_ON(pgd_val(merged_hyp_pgd[0]));
|
|
merged_hyp_pgd[0] = __pgd(__pa(hyp_pgd) | PMD_TYPE_TABLE);
|
|
|
|
/*
|
|
* Create another extended level entry that points to the boot HYP map,
|
|
* which contains an ID mapping of the HYP init code. We essentially
|
|
* merge the boot and runtime HYP maps by doing so, but they don't
|
|
* overlap anyway, so this is fine.
|
|
*/
|
|
idmap_idx = hyp_idmap_start >> VA_BITS;
|
|
VM_BUG_ON(pgd_val(merged_hyp_pgd[idmap_idx]));
|
|
merged_hyp_pgd[idmap_idx] = __pgd(__pa(boot_hyp_pgd) | PMD_TYPE_TABLE);
|
|
}
|
|
|
|
static inline unsigned int kvm_get_vmid_bits(void)
|
|
{
|
|
int reg = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
|
|
|
|
return (cpuid_feature_extract_unsigned_field(reg, ID_AA64MMFR1_VMIDBITS_SHIFT) == 2) ? 16 : 8;
|
|
}
|
|
|
|
#endif /* __ASSEMBLY__ */
|
|
#endif /* __ARM64_KVM_MMU_H__ */
|