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alistair23-linux/arch/arm64/include/asm/kvm_mmu.h

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/*
* 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 = __virt_to_phys(__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_SHIFT VA_BITS
#define HYP_PAGE_OFFSET_MASK ((UL(1) << HYP_PAGE_OFFSET_SHIFT) - 1)
/*
* Our virtual mapping for the idmap-ed MMU-enable code. Must be
* shared across all the page-tables. Conveniently, we use the last
* possible page, where no kernel mapping will ever exist.
*/
#define TRAMPOLINE_VA (HYP_PAGE_OFFSET_MASK & PAGE_MASK)
#ifdef __ASSEMBLY__
#include <asm/alternative.h>
#include <asm/cpufeature.h>
/*
* Convert a kernel VA into a HYP VA.
* reg: VA to be converted.
*/
.macro kern_hyp_va reg
alternative_if_not ARM64_HAS_VIRT_HOST_EXTN
and \reg, \reg, #HYP_PAGE_OFFSET_MASK
alternative_else
nop
alternative_endif
.endm
#else
arm64: KVM: Implement 48 VA support for KVM EL2 and Stage-2 This patch adds the necessary support for all host kernel PGSIZE and VA_SPACE configuration options for both EL2 and the Stage-2 page tables. However, for 40bit and 42bit PARange systems, the architecture mandates that VTCR_EL2.SL0 is maximum 1, resulting in fewer levels of stage-2 pagge tables than levels of host kernel page tables. At the same time, systems with a PARange > 42bit, we limit the IPA range by always setting VTCR_EL2.T0SZ to 24. To solve the situation with different levels of page tables for Stage-2 translation than the host kernel page tables, we allocate a dummy PGD with pointers to our actual inital level Stage-2 page table, in order for us to reuse the kernel pgtable manipulation primitives. Reproducing all these in KVM does not look pretty and unnecessarily complicates the 32-bit side. Systems with a PARange < 40bits are not yet supported. [ I have reworked this patch from its original form submitted by Jungseok to take the architecture constraints into consideration. There were too many changes from the original patch for me to preserve the authorship. Thanks to Catalin Marinas for his help in figuring out a good solution to this challenge. I have also fixed various bugs and missing error code handling from the original patch. - Christoffer ] Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-10 04:14:28 -06:00
#include <asm/pgalloc.h>
#include <asm/cachetype.h>
#include <asm/cacheflush.h>
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
#define KERN_TO_HYP(kva) ((unsigned long)kva & HYP_PAGE_OFFSET_MASK)
/*
* 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_boot_hyp_pgd(void);
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_mmu_get_boot_httbr(void);
phys_addr_t kvm_get_idmap_vector(void);
phys_addr_t kvm_get_idmap_start(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 void kvm_clean_pgd(pgd_t *pgd) {}
arm64: KVM: Implement 48 VA support for KVM EL2 and Stage-2 This patch adds the necessary support for all host kernel PGSIZE and VA_SPACE configuration options for both EL2 and the Stage-2 page tables. However, for 40bit and 42bit PARange systems, the architecture mandates that VTCR_EL2.SL0 is maximum 1, resulting in fewer levels of stage-2 pagge tables than levels of host kernel page tables. At the same time, systems with a PARange > 42bit, we limit the IPA range by always setting VTCR_EL2.T0SZ to 24. To solve the situation with different levels of page tables for Stage-2 translation than the host kernel page tables, we allocate a dummy PGD with pointers to our actual inital level Stage-2 page table, in order for us to reuse the kernel pgtable manipulation primitives. Reproducing all these in KVM does not look pretty and unnecessarily complicates the 32-bit side. Systems with a PARange < 40bits are not yet supported. [ I have reworked this patch from its original form submitted by Jungseok to take the architecture constraints into consideration. There were too many changes from the original patch for me to preserve the authorship. Thanks to Catalin Marinas for his help in figuring out a good solution to this challenge. I have also fixed various bugs and missing error code handling from the original patch. - Christoffer ] Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-10 04:14:28 -06:00
static inline void kvm_clean_pmd(pmd_t *pmd) {}
static inline void kvm_clean_pmd_entry(pmd_t *pmd) {}
static inline void kvm_clean_pte(pte_t *pte) {}
static inline void kvm_clean_pte_entry(pte_t *pte) {}
kvm: arm64: Enable hardware updates of the Access Flag for Stage 2 page tables The ARMv8.1 architecture extensions introduce support for hardware updates of the access and dirty information in page table entries. With VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the PTE_AF bit cleared in the stage 2 page table, instead of raising an Access Flag fault to EL2 the CPU sets the actual page table entry bit (10). To ensure that kernel modifications to the page table do not inadvertently revert a bit set by hardware updates, certain Stage 2 software pte/pmd operations must be performed atomically. The main user of the AF bit is the kvm_age_hva() mechanism. The kvm_age_hva_handler() function performs a "test and clear young" action on the pte/pmd. This needs to be atomic in respect of automatic hardware updates of the AF bit. Since the AF bit is in the same position for both Stage 1 and Stage 2, the patch reuses the existing ptep_test_and_clear_young() functionality if __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the existing pte_young/pte_mkold mechanism is preserved. The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have to perform atomic modifications in order to avoid a race with updates of the AF bit. The arm64 implementation has been re-written using exclusives. Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer argument and modify the pte/pmd in place. However, these functions are only used on local variables rather than actual page table entries, so it makes more sense to follow the pte_mkwrite() approach for stage 1 attributes. The change to kvm_s2pte_mkwrite() makes it clear that these functions do not modify the actual page table entries. The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit explicitly) do not need to be modified since hardware updates of the dirty status are not supported by KVM, so there is no possibility of losing such information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-13 10:57:37 -06:00
static inline pte_t kvm_s2pte_mkwrite(pte_t pte)
{
kvm: arm64: Enable hardware updates of the Access Flag for Stage 2 page tables The ARMv8.1 architecture extensions introduce support for hardware updates of the access and dirty information in page table entries. With VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the PTE_AF bit cleared in the stage 2 page table, instead of raising an Access Flag fault to EL2 the CPU sets the actual page table entry bit (10). To ensure that kernel modifications to the page table do not inadvertently revert a bit set by hardware updates, certain Stage 2 software pte/pmd operations must be performed atomically. The main user of the AF bit is the kvm_age_hva() mechanism. The kvm_age_hva_handler() function performs a "test and clear young" action on the pte/pmd. This needs to be atomic in respect of automatic hardware updates of the AF bit. Since the AF bit is in the same position for both Stage 1 and Stage 2, the patch reuses the existing ptep_test_and_clear_young() functionality if __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the existing pte_young/pte_mkold mechanism is preserved. The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have to perform atomic modifications in order to avoid a race with updates of the AF bit. The arm64 implementation has been re-written using exclusives. Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer argument and modify the pte/pmd in place. However, these functions are only used on local variables rather than actual page table entries, so it makes more sense to follow the pte_mkwrite() approach for stage 1 attributes. The change to kvm_s2pte_mkwrite() makes it clear that these functions do not modify the actual page table entries. The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit explicitly) do not need to be modified since hardware updates of the dirty status are not supported by KVM, so there is no possibility of losing such information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-13 10:57:37 -06:00
pte_val(pte) |= PTE_S2_RDWR;
return pte;
}
kvm: arm64: Enable hardware updates of the Access Flag for Stage 2 page tables The ARMv8.1 architecture extensions introduce support for hardware updates of the access and dirty information in page table entries. With VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the PTE_AF bit cleared in the stage 2 page table, instead of raising an Access Flag fault to EL2 the CPU sets the actual page table entry bit (10). To ensure that kernel modifications to the page table do not inadvertently revert a bit set by hardware updates, certain Stage 2 software pte/pmd operations must be performed atomically. The main user of the AF bit is the kvm_age_hva() mechanism. The kvm_age_hva_handler() function performs a "test and clear young" action on the pte/pmd. This needs to be atomic in respect of automatic hardware updates of the AF bit. Since the AF bit is in the same position for both Stage 1 and Stage 2, the patch reuses the existing ptep_test_and_clear_young() functionality if __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the existing pte_young/pte_mkold mechanism is preserved. The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have to perform atomic modifications in order to avoid a race with updates of the AF bit. The arm64 implementation has been re-written using exclusives. Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer argument and modify the pte/pmd in place. However, these functions are only used on local variables rather than actual page table entries, so it makes more sense to follow the pte_mkwrite() approach for stage 1 attributes. The change to kvm_s2pte_mkwrite() makes it clear that these functions do not modify the actual page table entries. The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit explicitly) do not need to be modified since hardware updates of the dirty status are not supported by KVM, so there is no possibility of losing such information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-13 10:57:37 -06:00
static inline pmd_t kvm_s2pmd_mkwrite(pmd_t pmd)
{
kvm: arm64: Enable hardware updates of the Access Flag for Stage 2 page tables The ARMv8.1 architecture extensions introduce support for hardware updates of the access and dirty information in page table entries. With VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the PTE_AF bit cleared in the stage 2 page table, instead of raising an Access Flag fault to EL2 the CPU sets the actual page table entry bit (10). To ensure that kernel modifications to the page table do not inadvertently revert a bit set by hardware updates, certain Stage 2 software pte/pmd operations must be performed atomically. The main user of the AF bit is the kvm_age_hva() mechanism. The kvm_age_hva_handler() function performs a "test and clear young" action on the pte/pmd. This needs to be atomic in respect of automatic hardware updates of the AF bit. Since the AF bit is in the same position for both Stage 1 and Stage 2, the patch reuses the existing ptep_test_and_clear_young() functionality if __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the existing pte_young/pte_mkold mechanism is preserved. The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have to perform atomic modifications in order to avoid a race with updates of the AF bit. The arm64 implementation has been re-written using exclusives. Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer argument and modify the pte/pmd in place. However, these functions are only used on local variables rather than actual page table entries, so it makes more sense to follow the pte_mkwrite() approach for stage 1 attributes. The change to kvm_s2pte_mkwrite() makes it clear that these functions do not modify the actual page table entries. The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit explicitly) do not need to be modified since hardware updates of the dirty status are not supported by KVM, so there is no possibility of losing such information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-13 10:57:37 -06:00
pmd_val(pmd) |= PMD_S2_RDWR;
return pmd;
}
static inline void kvm_set_s2pte_readonly(pte_t *pte)
{
kvm: arm64: Enable hardware updates of the Access Flag for Stage 2 page tables The ARMv8.1 architecture extensions introduce support for hardware updates of the access and dirty information in page table entries. With VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the PTE_AF bit cleared in the stage 2 page table, instead of raising an Access Flag fault to EL2 the CPU sets the actual page table entry bit (10). To ensure that kernel modifications to the page table do not inadvertently revert a bit set by hardware updates, certain Stage 2 software pte/pmd operations must be performed atomically. The main user of the AF bit is the kvm_age_hva() mechanism. The kvm_age_hva_handler() function performs a "test and clear young" action on the pte/pmd. This needs to be atomic in respect of automatic hardware updates of the AF bit. Since the AF bit is in the same position for both Stage 1 and Stage 2, the patch reuses the existing ptep_test_and_clear_young() functionality if __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the existing pte_young/pte_mkold mechanism is preserved. The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have to perform atomic modifications in order to avoid a race with updates of the AF bit. The arm64 implementation has been re-written using exclusives. Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer argument and modify the pte/pmd in place. However, these functions are only used on local variables rather than actual page table entries, so it makes more sense to follow the pte_mkwrite() approach for stage 1 attributes. The change to kvm_s2pte_mkwrite() makes it clear that these functions do not modify the actual page table entries. The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit explicitly) do not need to be modified since hardware updates of the dirty status are not supported by KVM, so there is no possibility of losing such information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-13 10:57:37 -06:00
pteval_t pteval;
unsigned long tmp;
asm volatile("// kvm_set_s2pte_readonly\n"
" prfm pstl1strm, %2\n"
"1: ldxr %0, %2\n"
" and %0, %0, %3 // clear PTE_S2_RDWR\n"
" orr %0, %0, %4 // set PTE_S2_RDONLY\n"
" stxr %w1, %0, %2\n"
" cbnz %w1, 1b\n"
: "=&r" (pteval), "=&r" (tmp), "+Q" (pte_val(*pte))
: "L" (~PTE_S2_RDWR), "L" (PTE_S2_RDONLY));
}
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: arm64: Enable hardware updates of the Access Flag for Stage 2 page tables The ARMv8.1 architecture extensions introduce support for hardware updates of the access and dirty information in page table entries. With VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the PTE_AF bit cleared in the stage 2 page table, instead of raising an Access Flag fault to EL2 the CPU sets the actual page table entry bit (10). To ensure that kernel modifications to the page table do not inadvertently revert a bit set by hardware updates, certain Stage 2 software pte/pmd operations must be performed atomically. The main user of the AF bit is the kvm_age_hva() mechanism. The kvm_age_hva_handler() function performs a "test and clear young" action on the pte/pmd. This needs to be atomic in respect of automatic hardware updates of the AF bit. Since the AF bit is in the same position for both Stage 1 and Stage 2, the patch reuses the existing ptep_test_and_clear_young() functionality if __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the existing pte_young/pte_mkold mechanism is preserved. The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have to perform atomic modifications in order to avoid a race with updates of the AF bit. The arm64 implementation has been re-written using exclusives. Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer argument and modify the pte/pmd in place. However, these functions are only used on local variables rather than actual page table entries, so it makes more sense to follow the pte_mkwrite() approach for stage 1 attributes. The change to kvm_s2pte_mkwrite() makes it clear that these functions do not modify the actual page table entries. The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit explicitly) do not need to be modified since hardware updates of the dirty status are not supported by KVM, so there is no possibility of losing such information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-13 10:57:37 -06:00
kvm_set_s2pte_readonly((pte_t *)pmd);
}
static inline bool kvm_s2pmd_readonly(pmd_t *pmd)
{
kvm: arm64: Enable hardware updates of the Access Flag for Stage 2 page tables The ARMv8.1 architecture extensions introduce support for hardware updates of the access and dirty information in page table entries. With VTCR_EL2.HA enabled (bit 21), when the CPU accesses an IPA with the PTE_AF bit cleared in the stage 2 page table, instead of raising an Access Flag fault to EL2 the CPU sets the actual page table entry bit (10). To ensure that kernel modifications to the page table do not inadvertently revert a bit set by hardware updates, certain Stage 2 software pte/pmd operations must be performed atomically. The main user of the AF bit is the kvm_age_hva() mechanism. The kvm_age_hva_handler() function performs a "test and clear young" action on the pte/pmd. This needs to be atomic in respect of automatic hardware updates of the AF bit. Since the AF bit is in the same position for both Stage 1 and Stage 2, the patch reuses the existing ptep_test_and_clear_young() functionality if __HAVE_ARCH_PTEP_TEST_AND_CLEAR_YOUNG is defined. Otherwise, the existing pte_young/pte_mkold mechanism is preserved. The kvm_set_s2pte_readonly() (and the corresponding pmd equivalent) have to perform atomic modifications in order to avoid a race with updates of the AF bit. The arm64 implementation has been re-written using exclusives. Currently, kvm_set_s2pte_writable() (and pmd equivalent) take a pointer argument and modify the pte/pmd in place. However, these functions are only used on local variables rather than actual page table entries, so it makes more sense to follow the pte_mkwrite() approach for stage 1 attributes. The change to kvm_s2pte_mkwrite() makes it clear that these functions do not modify the actual page table entries. The (pte|pmd)_mkyoung() uses on Stage 2 entries (setting the AF bit explicitly) do not need to be modified since hardware updates of the dirty status are not supported by KVM, so there is no possibility of losing such information. Signed-off-by: Catalin Marinas <catalin.marinas@arm.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-04-13 10:57:37 -06:00
return kvm_s2pte_readonly((pte_t *)pmd);
arm64: KVM: Implement 48 VA support for KVM EL2 and Stage-2 This patch adds the necessary support for all host kernel PGSIZE and VA_SPACE configuration options for both EL2 and the Stage-2 page tables. However, for 40bit and 42bit PARange systems, the architecture mandates that VTCR_EL2.SL0 is maximum 1, resulting in fewer levels of stage-2 pagge tables than levels of host kernel page tables. At the same time, systems with a PARange > 42bit, we limit the IPA range by always setting VTCR_EL2.T0SZ to 24. To solve the situation with different levels of page tables for Stage-2 translation than the host kernel page tables, we allocate a dummy PGD with pointers to our actual inital level Stage-2 page table, in order for us to reuse the kernel pgtable manipulation primitives. Reproducing all these in KVM does not look pretty and unnecessarily complicates the 32-bit side. Systems with a PARange < 40bits are not yet supported. [ I have reworked this patch from its original form submitted by Jungseok to take the architecture constraints into consideration. There were too many changes from the original patch for me to preserve the authorship. Thanks to Catalin Marinas for his help in figuring out a good solution to this challenge. I have also fixed various bugs and missing error code handling from the original patch. - Christoffer ] Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-10 04:14:28 -06:00
}
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)
arm64: KVM: Implement 48 VA support for KVM EL2 and Stage-2 This patch adds the necessary support for all host kernel PGSIZE and VA_SPACE configuration options for both EL2 and the Stage-2 page tables. However, for 40bit and 42bit PARange systems, the architecture mandates that VTCR_EL2.SL0 is maximum 1, resulting in fewer levels of stage-2 pagge tables than levels of host kernel page tables. At the same time, systems with a PARange > 42bit, we limit the IPA range by always setting VTCR_EL2.T0SZ to 24. To solve the situation with different levels of page tables for Stage-2 translation than the host kernel page tables, we allocate a dummy PGD with pointers to our actual inital level Stage-2 page table, in order for us to reuse the kernel pgtable manipulation primitives. Reproducing all these in KVM does not look pretty and unnecessarily complicates the 32-bit side. Systems with a PARange < 40bits are not yet supported. [ I have reworked this patch from its original form submitted by Jungseok to take the architecture constraints into consideration. There were too many changes from the original patch for me to preserve the authorship. Thanks to Catalin Marinas for his help in figuring out a good solution to this challenge. I have also fixed various bugs and missing error code handling from the original patch. - Christoffer ] Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-10 04:14:28 -06:00
#ifdef __PAGETABLE_PMD_FOLDED
#define hyp_pmd_table_empty(pmdp) (0)
arm64: KVM: Implement 48 VA support for KVM EL2 and Stage-2 This patch adds the necessary support for all host kernel PGSIZE and VA_SPACE configuration options for both EL2 and the Stage-2 page tables. However, for 40bit and 42bit PARange systems, the architecture mandates that VTCR_EL2.SL0 is maximum 1, resulting in fewer levels of stage-2 pagge tables than levels of host kernel page tables. At the same time, systems with a PARange > 42bit, we limit the IPA range by always setting VTCR_EL2.T0SZ to 24. To solve the situation with different levels of page tables for Stage-2 translation than the host kernel page tables, we allocate a dummy PGD with pointers to our actual inital level Stage-2 page table, in order for us to reuse the kernel pgtable manipulation primitives. Reproducing all these in KVM does not look pretty and unnecessarily complicates the 32-bit side. Systems with a PARange < 40bits are not yet supported. [ I have reworked this patch from its original form submitted by Jungseok to take the architecture constraints into consideration. There were too many changes from the original patch for me to preserve the authorship. Thanks to Catalin Marinas for his help in figuring out a good solution to this challenge. I have also fixed various bugs and missing error code handling from the original patch. - Christoffer ] Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-10 04:14:28 -06:00
#else
#define hyp_pmd_table_empty(pmdp) kvm_page_empty(pmdp)
arm64: KVM: Implement 48 VA support for KVM EL2 and Stage-2 This patch adds the necessary support for all host kernel PGSIZE and VA_SPACE configuration options for both EL2 and the Stage-2 page tables. However, for 40bit and 42bit PARange systems, the architecture mandates that VTCR_EL2.SL0 is maximum 1, resulting in fewer levels of stage-2 pagge tables than levels of host kernel page tables. At the same time, systems with a PARange > 42bit, we limit the IPA range by always setting VTCR_EL2.T0SZ to 24. To solve the situation with different levels of page tables for Stage-2 translation than the host kernel page tables, we allocate a dummy PGD with pointers to our actual inital level Stage-2 page table, in order for us to reuse the kernel pgtable manipulation primitives. Reproducing all these in KVM does not look pretty and unnecessarily complicates the 32-bit side. Systems with a PARange < 40bits are not yet supported. [ I have reworked this patch from its original form submitted by Jungseok to take the architecture constraints into consideration. There were too many changes from the original patch for me to preserve the authorship. Thanks to Catalin Marinas for his help in figuring out a good solution to this challenge. I have also fixed various bugs and missing error code handling from the original patch. - Christoffer ] Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Jungseok Lee <jungseoklee85@gmail.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-10-10 04:14:28 -06:00
#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;
}
kvm: rename pfn_t to kvm_pfn_t To date, we have implemented two I/O usage models for persistent memory, PMEM (a persistent "ram disk") and DAX (mmap persistent memory into userspace). This series adds a third, DAX-GUP, that allows DAX mappings to be the target of direct-i/o. It allows userspace to coordinate DMA/RDMA from/to persistent memory. The implementation leverages the ZONE_DEVICE mm-zone that went into 4.3-rc1 (also discussed at kernel summit) to flag pages that are owned and dynamically mapped by a device driver. The pmem driver, after mapping a persistent memory range into the system memmap via devm_memremap_pages(), arranges for DAX to distinguish pfn-only versus page-backed pmem-pfns via flags in the new pfn_t type. The DAX code, upon seeing a PFN_DEV+PFN_MAP flagged pfn, flags the resulting pte(s) inserted into the process page tables with a new _PAGE_DEVMAP flag. Later, when get_user_pages() is walking ptes it keys off _PAGE_DEVMAP to pin the device hosting the page range active. Finally, get_page() and put_page() are modified to take references against the device driver established page mapping. Finally, this need for "struct page" for persistent memory requires memory capacity to store the memmap array. Given the memmap array for a large pool of persistent may exhaust available DRAM introduce a mechanism to allocate the memmap from persistent memory. The new "struct vmem_altmap *" parameter to devm_memremap_pages() enables arch_add_memory() to use reserved pmem capacity rather than the page allocator. This patch (of 18): The core has developed a need for a "pfn_t" type [1]. Move the existing pfn_t in KVM to kvm_pfn_t [2]. [1]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002199.html [2]: https://lists.01.org/pipermail/linux-nvdimm/2015-September/002218.html Signed-off-by: Dan Williams <dan.j.williams@intel.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Cc: Paolo Bonzini <pbonzini@redhat.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-01-15 17:56:11 -07:00
static inline void __coherent_cache_guest_page(struct kvm_vcpu *vcpu,
kvm_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(va, size);
if (!icache_is_aliasing()) { /* PIPT */
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 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_system_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__ */