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Second round of fixes for KVM/ARM for 3.19. 

Fixes memory corruption issues on APM platforms and swapping issues on
 DMA-coherent systems.
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Merge tag 'kvm-arm-fixes-3.19-2' of git://git.kernel.org/pub/scm/linux/kernel/git/kvmarm/kvmarm into kvm-master

Second round of fixes for KVM/ARM for 3.19.

Fixes memory corruption issues on APM platforms and swapping issues on
DMA-coherent systems.
This commit is contained in:
Paolo Bonzini 2015-01-30 09:41:38 +01:00
parent 26bc420b59 0d3e4d4fad
commit 02512b2bd6
14 changed files with 327 additions and 178 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
arch/arm/include/asm/kvm_emulate.h
View File

@ -38,6 +38,16 @@ static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
vcpu->arch.hcr = HCR_GUEST_MASK;
}
static inline unsigned long vcpu_get_hcr(struct kvm_vcpu *vcpu)
{
return vcpu->arch.hcr;
}
static inline void vcpu_set_hcr(struct kvm_vcpu *vcpu, unsigned long hcr)
{
vcpu->arch.hcr = hcr;
}
static inline bool vcpu_mode_is_32bit(struct kvm_vcpu *vcpu)
{
return 1;

3
arch/arm/include/asm/kvm_host.h
View File

@ -125,9 +125,6 @@ struct kvm_vcpu_arch {
* Anything that is not used directly from assembly code goes
* here.
*/
/* dcache set/way operation pending */
int last_pcpu;
cpumask_t require_dcache_flush;
/* Don't run the guest on this vcpu */
bool pause;

77
arch/arm/include/asm/kvm_mmu.h
View File

@ -44,6 +44,7 @@
#ifndef __ASSEMBLY__
#include <linux/highmem.h>
#include <asm/cacheflush.h>
#include <asm/pgalloc.h>
@ -161,13 +162,10 @@ static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu)
return (vcpu->arch.cp15[c1_SCTLR] & 0b101) == 0b101;
}
static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva,
unsigned long size,
bool ipa_uncached)
static inline void __coherent_cache_guest_page(struct kvm_vcpu *vcpu, pfn_t pfn,
unsigned long size,
bool ipa_uncached)
{
if (!vcpu_has_cache_enabled(vcpu) || ipa_uncached)
kvm_flush_dcache_to_poc((void *)hva, size);
/*
* 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
@ -179,18 +177,77 @@ static inline void coherent_cache_guest_page(struct kvm_vcpu *vcpu, hva_t hva,
*
* 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).
*
* We need to do this through a kernel mapping (using the
* user-space mapping has proved to be the wrong
* solution). For that, we need to kmap one page at a time,
* and iterate over the range.
*/
if (icache_is_pipt()) {
__cpuc_coherent_user_range(hva, hva + size);
} else if (!icache_is_vivt_asid_tagged()) {
bool need_flush = !vcpu_has_cache_enabled(vcpu) || ipa_uncached;
VM_BUG_ON(size & PAGE_MASK);
if (!need_flush && !icache_is_pipt())
goto vipt_cache;
while (size) {
void *va = kmap_atomic_pfn(pfn);
if (need_flush)
kvm_flush_dcache_to_poc(va, PAGE_SIZE);
if (icache_is_pipt())
__cpuc_coherent_user_range((unsigned long)va,
(unsigned long)va + PAGE_SIZE);
size -= PAGE_SIZE;
pfn++;
kunmap_atomic(va);
}
vipt_cache:
if (!icache_is_pipt() && !icache_is_vivt_asid_tagged()) {
/* any kind of VIPT cache */
__flush_icache_all();
}
}
static inline void __kvm_flush_dcache_pte(pte_t pte)
{
void *va = kmap_atomic(pte_page(pte));
kvm_flush_dcache_to_poc(va, PAGE_SIZE);
kunmap_atomic(va);
}
static inline void __kvm_flush_dcache_pmd(pmd_t pmd)
{
unsigned long size = PMD_SIZE;
pfn_t pfn = pmd_pfn(pmd);
while (size) {
void *va = kmap_atomic_pfn(pfn);
kvm_flush_dcache_to_poc(va, PAGE_SIZE);
pfn++;
size -= PAGE_SIZE;
kunmap_atomic(va);
}
}
static inline void __kvm_flush_dcache_pud(pud_t pud)
{
}
#define kvm_virt_to_phys(x) virt_to_idmap((unsigned long)(x))
void stage2_flush_vm(struct kvm *kvm);
void kvm_set_way_flush(struct kvm_vcpu *vcpu);
void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled);
#endif /* !__ASSEMBLY__ */

10
arch/arm/kvm/arm.c
View File

@ -281,15 +281,6 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
vcpu->cpu = cpu;
vcpu->arch.host_cpu_context = this_cpu_ptr(kvm_host_cpu_state);
/*
* Check whether this vcpu requires the cache to be flushed on
* this physical CPU. This is a consequence of doing dcache
* operations by set/way on this vcpu. We do it here to be in
* a non-preemptible section.
*/
if (cpumask_test_and_clear_cpu(cpu, &vcpu->arch.require_dcache_flush))
flush_cache_all(); /* We'd really want v7_flush_dcache_all() */
kvm_arm_set_running_vcpu(vcpu);
}
@ -541,7 +532,6 @@ int kvm_arch_vcpu_ioctl_run(struct kvm_vcpu *vcpu, struct kvm_run *run)
ret = kvm_call_hyp(__kvm_vcpu_run, vcpu);
vcpu->mode = OUTSIDE_GUEST_MODE;
vcpu->arch.last_pcpu = smp_processor_id();
kvm_guest_exit();
trace_kvm_exit(*vcpu_pc(vcpu));
/*

70
arch/arm/kvm/coproc.c
View File

@ -189,82 +189,40 @@ static bool access_l2ectlr(struct kvm_vcpu *vcpu,
return true;
}
/* See note at ARM ARM B1.14.4 */
/*
* See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
*/
static bool access_dcsw(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
{
unsigned long val;
int cpu;
if (!p->is_write)
return read_from_write_only(vcpu, p);
cpu = get_cpu();
cpumask_setall(&vcpu->arch.require_dcache_flush);
cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush);
/* If we were already preempted, take the long way around */
if (cpu != vcpu->arch.last_pcpu) {
flush_cache_all();
goto done;
}
val = *vcpu_reg(vcpu, p->Rt1);
switch (p->CRm) {
case 6: /* Upgrade DCISW to DCCISW, as per HCR.SWIO */
case 14: /* DCCISW */
asm volatile("mcr p15, 0, %0, c7, c14, 2" : : "r" (val));
break;
case 10: /* DCCSW */
asm volatile("mcr p15, 0, %0, c7, c10, 2" : : "r" (val));
break;
}
done:
put_cpu();
kvm_set_way_flush(vcpu);
return true;
}
/*
* Generic accessor for VM registers. Only called as long as HCR_TVM
* is set.
* is set. If the guest enables the MMU, we stop trapping the VM
* sys_regs and leave it in complete control of the caches.
*
* Used by the cpu-specific code.
*/
static bool access_vm_reg(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
bool access_vm_reg(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
{
bool was_enabled = vcpu_has_cache_enabled(vcpu);
BUG_ON(!p->is_write);
vcpu->arch.cp15[r->reg] = *vcpu_reg(vcpu, p->Rt1);
if (p->is_64bit)
vcpu->arch.cp15[r->reg + 1] = *vcpu_reg(vcpu, p->Rt2);
return true;
}
/*
* SCTLR accessor. Only called as long as HCR_TVM is set. If the
* guest enables the MMU, we stop trapping the VM sys_regs and leave
* it in complete control of the caches.
*
* Used by the cpu-specific code.
*/
bool access_sctlr(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r)
{
access_vm_reg(vcpu, p, r);
if (vcpu_has_cache_enabled(vcpu)) { /* MMU+Caches enabled? */
vcpu->arch.hcr &= ~HCR_TVM;
stage2_flush_vm(vcpu->kvm);
}
kvm_toggle_cache(vcpu, was_enabled);
return true;
}

6
arch/arm/kvm/coproc.h
View File

@ -153,8 +153,8 @@ static inline int cmp_reg(const struct coproc_reg *i1,
#define is64 .is_64 = true
#define is32 .is_64 = false
bool access_sctlr(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r);
bool access_vm_reg(struct kvm_vcpu *vcpu,
const struct coproc_params *p,
const struct coproc_reg *r);
#endif /* __ARM_KVM_COPROC_LOCAL_H__ */

2
arch/arm/kvm/coproc_a15.c
View File

@ -34,7 +34,7 @@
static const struct coproc_reg a15_regs[] = {
/* SCTLR: swapped by interrupt.S. */
{ CRn( 1), CRm( 0), Op1( 0), Op2( 0), is32,
access_sctlr, reset_val, c1_SCTLR, 0x00C50078 },
access_vm_reg, reset_val, c1_SCTLR, 0x00C50078 },
};
static struct kvm_coproc_target_table a15_target_table = {

2
arch/arm/kvm/coproc_a7.c
View File

@ -37,7 +37,7 @@
static const struct coproc_reg a7_regs[] = {
/* SCTLR: swapped by interrupt.S. */
{ CRn( 1), CRm( 0), Op1( 0), Op2( 0), is32,
access_sctlr, reset_val, c1_SCTLR, 0x00C50878 },
access_vm_reg, reset_val, c1_SCTLR, 0x00C50878 },
};
static struct kvm_coproc_target_table a7_target_table = {

164
arch/arm/kvm/mmu.c
View File

@ -58,6 +58,26 @@ static void kvm_tlb_flush_vmid_ipa(struct kvm *kvm, phys_addr_t ipa)
kvm_call_hyp(__kvm_tlb_flush_vmid_ipa, kvm, ipa);
}
/*
* D-Cache management functions. They take the page table entries by
* value, as they are flushing the cache using the kernel mapping (or
* kmap on 32bit).
*/
static void kvm_flush_dcache_pte(pte_t pte)
{
__kvm_flush_dcache_pte(pte);
}
static void kvm_flush_dcache_pmd(pmd_t pmd)
{
__kvm_flush_dcache_pmd(pmd);
}
static void kvm_flush_dcache_pud(pud_t pud)
{
__kvm_flush_dcache_pud(pud);
}
static int mmu_topup_memory_cache(struct kvm_mmu_memory_cache *cache,
int min, int max)
{
@ -119,6 +139,26 @@ static void clear_pmd_entry(struct kvm *kvm, pmd_t *pmd, phys_addr_t addr)
put_page(virt_to_page(pmd));
}
/*
* Unmapping vs dcache management:
*
* If a guest maps certain memory pages as uncached, all writes will
* bypass the data cache and go directly to RAM. However, the CPUs
* can still speculate reads (not writes) and fill cache lines with
* data.
*
* Those cache lines will be *clean* cache lines though, so a
* clean+invalidate operation is equivalent to an invalidate
* operation, because no cache lines are marked dirty.
*
* Those clean cache lines could be filled prior to an uncached write
* by the guest, and the cache coherent IO subsystem would therefore
* end up writing old data to disk.
*
* This is why right after unmapping a page/section and invalidating
* the corresponding TLBs, we call kvm_flush_dcache_p*() to make sure
* the IO subsystem will never hit in the cache.
*/
static void unmap_ptes(struct kvm *kvm, pmd_t *pmd,
phys_addr_t addr, phys_addr_t end)
{
@ -128,9 +168,16 @@ static void unmap_ptes(struct kvm *kvm, pmd_t *pmd,
start_pte = pte = pte_offset_kernel(pmd, addr);
do {
if (!pte_none(*pte)) {
pte_t old_pte = *pte;
kvm_set_pte(pte, __pte(0));
put_page(virt_to_page(pte));
kvm_tlb_flush_vmid_ipa(kvm, addr);
/* No need to invalidate the cache for device mappings */
if ((pte_val(old_pte) & PAGE_S2_DEVICE) != PAGE_S2_DEVICE)
kvm_flush_dcache_pte(old_pte);
put_page(virt_to_page(pte));
}
} while (pte++, addr += PAGE_SIZE, addr != end);
@ -149,8 +196,13 @@ static void unmap_pmds(struct kvm *kvm, pud_t *pud,
next = kvm_pmd_addr_end(addr, end);
if (!pmd_none(*pmd)) {
if (kvm_pmd_huge(*pmd)) {
pmd_t old_pmd = *pmd;
pmd_clear(pmd);
kvm_tlb_flush_vmid_ipa(kvm, addr);
kvm_flush_dcache_pmd(old_pmd);
put_page(virt_to_page(pmd));
} else {
unmap_ptes(kvm, pmd, addr, next);
@ -173,8 +225,13 @@ static void unmap_puds(struct kvm *kvm, pgd_t *pgd,
next = kvm_pud_addr_end(addr, end);
if (!pud_none(*pud)) {
if (pud_huge(*pud)) {
pud_t old_pud = *pud;
pud_clear(pud);
kvm_tlb_flush_vmid_ipa(kvm, addr);
kvm_flush_dcache_pud(old_pud);
put_page(virt_to_page(pud));
} else {
unmap_pmds(kvm, pud, addr, next);
@ -209,10 +266,9 @@ static void stage2_flush_ptes(struct kvm *kvm, pmd_t *pmd,
pte = pte_offset_kernel(pmd, addr);
do {
if (!pte_none(*pte)) {
hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT);
kvm_flush_dcache_to_poc((void*)hva, PAGE_SIZE);
}
if (!pte_none(*pte) &&
(pte_val(*pte) & PAGE_S2_DEVICE) != PAGE_S2_DEVICE)
kvm_flush_dcache_pte(*pte);
} while (pte++, addr += PAGE_SIZE, addr != end);
}
@ -226,12 +282,10 @@ static void stage2_flush_pmds(struct kvm *kvm, pud_t *pud,
do {
next = kvm_pmd_addr_end(addr, end);
if (!pmd_none(*pmd)) {
if (kvm_pmd_huge(*pmd)) {
hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT);
kvm_flush_dcache_to_poc((void*)hva, PMD_SIZE);
} else {
if (kvm_pmd_huge(*pmd))
kvm_flush_dcache_pmd(*pmd);
else
stage2_flush_ptes(kvm, pmd, addr, next);
}
}
} while (pmd++, addr = next, addr != end);
}
@ -246,12 +300,10 @@ static void stage2_flush_puds(struct kvm *kvm, pgd_t *pgd,
do {
next = kvm_pud_addr_end(addr, end);
if (!pud_none(*pud)) {
if (pud_huge(*pud)) {
hva_t hva = gfn_to_hva(kvm, addr >> PAGE_SHIFT);
kvm_flush_dcache_to_poc((void*)hva, PUD_SIZE);
} else {
if (pud_huge(*pud))
kvm_flush_dcache_pud(*pud);
else
stage2_flush_pmds(kvm, pud, addr, next);
}
}
} while (pud++, addr = next, addr != end);
}
@ -278,7 +330,7 @@ static void stage2_flush_memslot(struct kvm *kvm,
* Go through the stage 2 page tables and invalidate any cache lines
* backing memory already mapped to the VM.
*/
void stage2_flush_vm(struct kvm *kvm)
static void stage2_flush_vm(struct kvm *kvm)
{
struct kvm_memslots *slots;
struct kvm_memory_slot *memslot;
@ -905,6 +957,12 @@ static bool kvm_is_device_pfn(unsigned long pfn)
return !pfn_valid(pfn);
}
static void coherent_cache_guest_page(struct kvm_vcpu *vcpu, pfn_t pfn,
unsigned long size, bool uncached)
{
__coherent_cache_guest_page(vcpu, pfn, size, uncached);
}
static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
struct kvm_memory_slot *memslot, unsigned long hva,
unsigned long fault_status)
@ -994,8 +1052,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
kvm_set_s2pmd_writable(&new_pmd);
kvm_set_pfn_dirty(pfn);
}
coherent_cache_guest_page(vcpu, hva & PMD_MASK, PMD_SIZE,
fault_ipa_uncached);
coherent_cache_guest_page(vcpu, pfn, PMD_SIZE, fault_ipa_uncached);
ret = stage2_set_pmd_huge(kvm, memcache, fault_ipa, &new_pmd);
} else {
pte_t new_pte = pfn_pte(pfn, mem_type);
@ -1003,8 +1060,7 @@ static int user_mem_abort(struct kvm_vcpu *vcpu, phys_addr_t fault_ipa,
kvm_set_s2pte_writable(&new_pte);
kvm_set_pfn_dirty(pfn);
}
coherent_cache_guest_page(vcpu, hva, PAGE_SIZE,
fault_ipa_uncached);
coherent_cache_guest_page(vcpu, pfn, PAGE_SIZE, fault_ipa_uncached);
ret = stage2_set_pte(kvm, memcache, fault_ipa, &new_pte,
pgprot_val(mem_type) == pgprot_val(PAGE_S2_DEVICE));
}
@ -1411,3 +1467,71 @@ void kvm_arch_flush_shadow_memslot(struct kvm *kvm,
unmap_stage2_range(kvm, gpa, size);
spin_unlock(&kvm->mmu_lock);
}
/*
* See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
*
* Main problems:
* - S/W ops are local to a CPU (not broadcast)
* - We have line migration behind our back (speculation)
* - System caches don't support S/W at all (damn!)
*
* In the face of the above, the best we can do is to try and convert
* S/W ops to VA ops. Because the guest is not allowed to infer the
* S/W to PA mapping, it can only use S/W to nuke the whole cache,
* which is a rather good thing for us.
*
* Also, it is only used when turning caches on/off ("The expected
* usage of the cache maintenance instructions that operate by set/way
* is associated with the cache maintenance instructions associated
* with the powerdown and powerup of caches, if this is required by
* the implementation.").
*
* We use the following policy:
*
* - If we trap a S/W operation, we enable VM trapping to detect
* caches being turned on/off, and do a full clean.
*
* - We flush the caches on both caches being turned on and off.
*
* - Once the caches are enabled, we stop trapping VM ops.
*/
void kvm_set_way_flush(struct kvm_vcpu *vcpu)
{
unsigned long hcr = vcpu_get_hcr(vcpu);
/*
* If this is the first time we do a S/W operation
* (i.e. HCR_TVM not set) flush the whole memory, and set the
* VM trapping.
*
* Otherwise, rely on the VM trapping to wait for the MMU +
* Caches to be turned off. At that point, we'll be able to
* clean the caches again.
*/
if (!(hcr & HCR_TVM)) {
trace_kvm_set_way_flush(*vcpu_pc(vcpu),
vcpu_has_cache_enabled(vcpu));
stage2_flush_vm(vcpu->kvm);
vcpu_set_hcr(vcpu, hcr | HCR_TVM);
}
}
void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled)
{
bool now_enabled = vcpu_has_cache_enabled(vcpu);
/*
* If switching the MMU+caches on, need to invalidate the caches.
* If switching it off, need to clean the caches.
* Clean + invalidate does the trick always.
*/
if (now_enabled != was_enabled)
stage2_flush_vm(vcpu->kvm);
/* Caches are now on, stop trapping VM ops (until a S/W op) */
if (now_enabled)
vcpu_set_hcr(vcpu, vcpu_get_hcr(vcpu) & ~HCR_TVM);
trace_kvm_toggle_cache(*vcpu_pc(vcpu), was_enabled, now_enabled);
}

39
arch/arm/kvm/trace.h
View File

@ -223,6 +223,45 @@ TRACE_EVENT(kvm_hvc,
__entry->vcpu_pc, __entry->r0, __entry->imm)
);
TRACE_EVENT(kvm_set_way_flush,
TP_PROTO(unsigned long vcpu_pc, bool cache),
TP_ARGS(vcpu_pc, cache),
TP_STRUCT__entry(
__field( unsigned long, vcpu_pc )
__field( bool, cache )
),
TP_fast_assign(
__entry->vcpu_pc = vcpu_pc;
__entry->cache = cache;
),
TP_printk("S/W flush at 0x%016lx (cache %s)",
__entry->vcpu_pc, __entry->cache ? "on" : "off")
);
TRACE_EVENT(kvm_toggle_cache,
TP_PROTO(unsigned long vcpu_pc, bool was, bool now),
TP_ARGS(vcpu_pc, was, now),
TP_STRUCT__entry(
__field( unsigned long, vcpu_pc )
__field( bool, was )
__field( bool, now )
),
TP_fast_assign(
__entry->vcpu_pc = vcpu_pc;
__entry->was = was;
__entry->now = now;
),
TP_printk("VM op at 0x%016lx (cache was %s, now %s)",
__entry->vcpu_pc, __entry->was ? "on" : "off",
__entry->now ? "on" : "off")
);
#endif /* _TRACE_KVM_H */
#undef TRACE_INCLUDE_PATH

10
arch/arm64/include/asm/kvm_emulate.h
View File

@ -45,6 +45,16 @@ static inline void vcpu_reset_hcr(struct kvm_vcpu *vcpu)
vcpu->arch.hcr_el2 &= ~HCR_RW;
}
static inline unsigned long vcpu_get_hcr(struct kvm_vcpu *vcpu)
{
return vcpu->arch.hcr_el2;
}
static inline void vcpu_set_hcr(struct kvm_vcpu *vcpu, unsigned long hcr)
{
vcpu->arch.hcr_el2 = hcr;
}
static inline unsigned long *vcpu_pc(const struct kvm_vcpu *vcpu)
{
return (unsigned long *)&vcpu_gp_regs(vcpu)->regs.pc;

3
arch/arm64/include/asm/kvm_host.h
View File

@ -116,9 +116,6 @@ struct kvm_vcpu_arch {
* Anything that is not used directly from assembly code goes
* here.
*/
/* dcache set/way operation pending */
int last_pcpu;
cpumask_t require_dcache_flush;
/* Don't run the guest */
bool pause;

34
arch/arm64/include/asm/kvm_mmu.h
View File

@ -243,24 +243,46 @@ 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, hva_t hva,
unsigned long size,
bool ipa_uncached)
static inline void __coherent_cache_guest_page(struct kvm_vcpu *vcpu, pfn_t pfn,
unsigned long size,
bool ipa_uncached)
{
void *va = page_address(pfn_to_page(pfn));
if (!vcpu_has_cache_enabled(vcpu) || ipa_uncached)
kvm_flush_dcache_to_poc((void *)hva, size);
kvm_flush_dcache_to_poc(va, size);
if (!icache_is_aliasing()) { /* PIPT */
flush_icache_range(hva, hva + size);
flush_icache_range((unsigned long)va,
(unsigned long)va + size);
} else if (!icache_is_aivivt()) { /* non ASID-tagged VIVT */
/* any kind of VIPT cache */
__flush_icache_all();
}
}
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) __virt_to_phys((unsigned long)(x))
void stage2_flush_vm(struct kvm *kvm);
void kvm_set_way_flush(struct kvm_vcpu *vcpu);
void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled);
#endif /* __ASSEMBLY__ */
#endif /* __ARM64_KVM_MMU_H__ */

75
arch/arm64/kvm/sys_regs.c
View File

@ -69,68 +69,31 @@ static u32 get_ccsidr(u32 csselr)
return ccsidr;
}
static void do_dc_cisw(u32 val)
{
asm volatile("dc cisw, %x0" : : "r" (val));
dsb(ish);
}
static void do_dc_csw(u32 val)
{
asm volatile("dc csw, %x0" : : "r" (val));
dsb(ish);
}
/* See note at ARM ARM B1.14.4 */
/*
* See note at ARMv7 ARM B1.14.4 (TL;DR: S/W ops are not easily virtualized).
*/
static bool access_dcsw(struct kvm_vcpu *vcpu,
const struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
unsigned long val;
int cpu;
if (!p->is_write)
return read_from_write_only(vcpu, p);
cpu = get_cpu();
cpumask_setall(&vcpu->arch.require_dcache_flush);
cpumask_clear_cpu(cpu, &vcpu->arch.require_dcache_flush);
/* If we were already preempted, take the long way around */
if (cpu != vcpu->arch.last_pcpu) {
flush_cache_all();
goto done;
}
val = *vcpu_reg(vcpu, p->Rt);
switch (p->CRm) {
case 6: /* Upgrade DCISW to DCCISW, as per HCR.SWIO */
case 14: /* DCCISW */
do_dc_cisw(val);
break;
case 10: /* DCCSW */
do_dc_csw(val);
break;
}
done:
put_cpu();
kvm_set_way_flush(vcpu);
return true;
}
/*
* Generic accessor for VM registers. Only called as long as HCR_TVM
* is set.
* is set. If the guest enables the MMU, we stop trapping the VM
* sys_regs and leave it in complete control of the caches.
*/
static bool access_vm_reg(struct kvm_vcpu *vcpu,
const struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
unsigned long val;
bool was_enabled = vcpu_has_cache_enabled(vcpu);
BUG_ON(!p->is_write);
@ -143,25 +106,7 @@ static bool access_vm_reg(struct kvm_vcpu *vcpu,
vcpu_cp15_64_low(vcpu, r->reg) = val & 0xffffffffUL;
}
return true;
}
/*
* SCTLR_EL1 accessor. Only called as long as HCR_TVM is set. If the
* guest enables the MMU, we stop trapping the VM sys_regs and leave
* it in complete control of the caches.
*/
static bool access_sctlr(struct kvm_vcpu *vcpu,
const struct sys_reg_params *p,
const struct sys_reg_desc *r)
{
access_vm_reg(vcpu, p, r);
if (vcpu_has_cache_enabled(vcpu)) { /* MMU+Caches enabled? */
vcpu->arch.hcr_el2 &= ~HCR_TVM;
stage2_flush_vm(vcpu->kvm);
}
kvm_toggle_cache(vcpu, was_enabled);
return true;
}
@ -377,7 +322,7 @@ static const struct sys_reg_desc sys_reg_descs[] = {
NULL, reset_mpidr, MPIDR_EL1 },
/* SCTLR_EL1 */
{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b000),
access_sctlr, reset_val, SCTLR_EL1, 0x00C50078 },
access_vm_reg, reset_val, SCTLR_EL1, 0x00C50078 },
/* CPACR_EL1 */
{ Op0(0b11), Op1(0b000), CRn(0b0001), CRm(0b0000), Op2(0b010),
NULL, reset_val, CPACR_EL1, 0 },
@ -657,7 +602,7 @@ static const struct sys_reg_desc cp14_64_regs[] = {
* register).
*/
static const struct sys_reg_desc cp15_regs[] = {
{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), access_sctlr, NULL, c1_SCTLR },
{ Op1( 0), CRn( 1), CRm( 0), Op2( 0), access_vm_reg, NULL, c1_SCTLR },
{ Op1( 0), CRn( 2), CRm( 0), Op2( 0), access_vm_reg, NULL, c2_TTBR0 },
{ Op1( 0), CRn( 2), CRm( 0), Op2( 1), access_vm_reg, NULL, c2_TTBR1 },
{ Op1( 0), CRn( 2), CRm( 0), Op2( 2), access_vm_reg, NULL, c2_TTBCR },