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

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arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
/*
* 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>
arm64: KVM: Add support for 16-bit VMID The ARMv8.1 architecture extension allows to choose between 8-bit and 16-bit of VMID, so use this capability for KVM. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-11-16 04:28:18 -07:00
#include <asm/cpufeature.h>
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
/*
arm64: KVM: VHE: Patch out kern_hyp_va The kern_hyp_va macro is pretty meaninless with VHE, as there is only one mapping - the kernel one. In order to keep the code readable and efficient, use runtime patching to replace the 'and' instruction used to compute the VA with a 'nop'. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 06:50:34 -07:00
* As ARMv8.0 only has the TTBR0_EL2 register, we cannot express
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
* "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
arm64: KVM: Merged page tables documentation Since dealing with VA ranges tends to hurt my brain badly, let's start with a bit of documentation that will hopefully help understanding what comes next... Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-30 11:40:34 -06:00
* kernel address). We need to find out how many bits to mask.
arm64: KVM: VHE: Patch out kern_hyp_va The kern_hyp_va macro is pretty meaninless with VHE, as there is only one mapping - the kernel one. In order to keep the code readable and efficient, use runtime patching to replace the 'and' instruction used to compute the VA with a 'nop'. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 06:50:34 -07:00
*
arm64: KVM: Merged page tables documentation Since dealing with VA ranges tends to hurt my brain badly, let's start with a bit of documentation that will hopefully help understanding what comes next... Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-30 11:40:34 -06:00
* 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:
*
arm64: Use __pa_symbol for kernel symbols __pa_symbol is technically the marcro that should be used for kernel symbols. Switch to this as a pre-requisite for DEBUG_VIRTUAL which will do bounds checking. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-10 14:35:49 -07:00
* T = __pa_symbol(__hyp_idmap_text_start)
arm64: KVM: Merged page tables documentation Since dealing with VA ranges tends to hurt my brain badly, let's start with a bit of documentation that will hopefully help understanding what comes next... Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-30 11:40:34 -06:00
* 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.
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
*/
arm64: KVM: Define HYP offset masks Define the two possible HYP VA regions in terms of VA_BITS, and keep HYP_PAGE_OFFSET_MASK as a temporary compatibility definition. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-30 11:40:39 -06:00
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
#ifdef __ASSEMBLY__
arm64: KVM: VHE: Patch out kern_hyp_va The kern_hyp_va macro is pretty meaninless with VHE, as there is only one mapping - the kernel one. In order to keep the code readable and efficient, use runtime patching to replace the 'and' instruction used to compute the VA with a 'nop'. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-01-29 06:50:34 -07:00
#include <asm/alternative.h>
#include <asm/cpufeature.h>
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
/*
* Convert a kernel VA into a HYP VA.
* reg: VA to be converted.
arm64: KVM: Refactor kern_hyp_va to deal with multiple offsets As we move towards a selectable HYP VA range, it is obvious that we don't want to test a variable to find out if we need to use the bottom VA range, the top VA range, or use the address as is (for VHE). Instead, we can expand our current helper to generate the right mask or nop with code patching. We default to using the top VA space, with alternatives to switch to the bottom one or to nop out the instructions. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-30 11:40:40 -06:00
*
arm64: KVM: Dynamically patch the kernel/hyp VA mask So far, we're using a complicated sequence of alternatives to patch the kernel/hyp VA mask on non-VHE, and NOP out the masking altogether when on VHE. The newly introduced dynamic patching gives us the opportunity to simplify that code by patching a single instruction with the correct mask (instead of the mind bending cumulative masking we have at the moment) or even a single NOP on VHE. This also adds some initial code that will allow the patching callback to switch to a more complex patching. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-12-03 10:36:55 -07:00
* The actual code generation takes place in kvm_update_va_mask, and
* the instructions below are only there to reserve the space and
* perform the register allocation (kvm_update_va_mask uses the
* specific registers encoded in the instructions).
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
*/
.macro kern_hyp_va reg
arm64: KVM: Dynamically patch the kernel/hyp VA mask So far, we're using a complicated sequence of alternatives to patch the kernel/hyp VA mask on non-VHE, and NOP out the masking altogether when on VHE. The newly introduced dynamic patching gives us the opportunity to simplify that code by patching a single instruction with the correct mask (instead of the mind bending cumulative masking we have at the moment) or even a single NOP on VHE. This also adds some initial code that will allow the patching callback to switch to a more complex patching. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-12-03 10:36:55 -07:00
alternative_cb kvm_update_va_mask
and \reg, \reg, #1
alternative_cb_end
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
.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>
arm64: cache: Merge cachetype.h into cache.h cachetype.h and cache.h are small and both obviously related to caches. Merge them together to reduce clutter. Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-10 13:32:23 -07:00
#include <asm/cache.h>
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
#include <asm/cacheflush.h>
arm64: KVM: use ID map with increased VA range if required This patch modifies the HYP init code so it can deal with system RAM residing at an offset which exceeds the reach of VA_BITS. Like for EL1, this involves configuring an additional level of translation for the ID map. However, in case of EL2, this implies that all translations use the extra level, as we cannot seamlessly switch between translation tables with different numbers of translation levels. So add an extra translation table at the root level. Since the ID map and the runtime HYP map are guaranteed not to overlap, they can share this root level, and we can essentially merge these two tables into one. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-19 10:42:28 -06:00
#include <asm/mmu_context.h>
#include <asm/pgtable.h>
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
arm64: KVM: Dynamically patch the kernel/hyp VA mask So far, we're using a complicated sequence of alternatives to patch the kernel/hyp VA mask on non-VHE, and NOP out the masking altogether when on VHE. The newly introduced dynamic patching gives us the opportunity to simplify that code by patching a single instruction with the correct mask (instead of the mind bending cumulative masking we have at the moment) or even a single NOP on VHE. This also adds some initial code that will allow the patching callback to switch to a more complex patching. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-12-03 10:36:55 -07:00
void kvm_update_va_mask(struct alt_instr *alt,
__le32 *origptr, __le32 *updptr, int nr_inst);
arm64: KVM: Refactor kern_hyp_va to deal with multiple offsets As we move towards a selectable HYP VA range, it is obvious that we don't want to test a variable to find out if we need to use the bottom VA range, the top VA range, or use the address as is (for VHE). Instead, we can expand our current helper to generate the right mask or nop with code patching. We default to using the top VA space, with alternatives to switch to the bottom one or to nop out the instructions. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-30 11:40:40 -06:00
static inline unsigned long __kern_hyp_va(unsigned long v)
{
arm64: KVM: Dynamically patch the kernel/hyp VA mask So far, we're using a complicated sequence of alternatives to patch the kernel/hyp VA mask on non-VHE, and NOP out the masking altogether when on VHE. The newly introduced dynamic patching gives us the opportunity to simplify that code by patching a single instruction with the correct mask (instead of the mind bending cumulative masking we have at the moment) or even a single NOP on VHE. This also adds some initial code that will allow the patching callback to switch to a more complex patching. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-12-03 10:36:55 -07:00
asm volatile(ALTERNATIVE_CB("and %0, %0, #1\n",
kvm_update_va_mask)
: "+r" (v));
arm64: KVM: Refactor kern_hyp_va to deal with multiple offsets As we move towards a selectable HYP VA range, it is obvious that we don't want to test a variable to find out if we need to use the bottom VA range, the top VA range, or use the address as is (for VHE). Instead, we can expand our current helper to generate the right mask or nop with code patching. We default to using the top VA space, with alternatives to switch to the bottom one or to nop out the instructions. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-30 11:40:40 -06:00
return v;
}
arm/arm64: KVM: Perform local TLB invalidation when multiplexing vcpus on a single CPU Architecturally, TLBs are private to the (physical) CPU they're associated with. But when multiple vcpus from the same VM are being multiplexed on the same CPU, the TLBs are not private to the vcpus (and are actually shared across the VMID). Let's consider the following scenario: - vcpu-0 maps PA to VA - vcpu-1 maps PA' to VA If run on the same physical CPU, vcpu-1 can hit TLB entries generated by vcpu-0 accesses, and access the wrong physical page. The solution to this is to keep a per-VM map of which vcpu ran last on each given physical CPU, and invalidate local TLBs when switching to a different vcpu from the same VM. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-10-18 11:37:49 -06:00
#define kern_hyp_va(v) ((typeof(v))(__kern_hyp_va((unsigned long)(v))))
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
KVM: arm/arm64: Do not use kern_hyp_va() with kvm_vgic_global_state kvm_vgic_global_state is part of the read-only section, and is usually accessed using a PC-relative address generation (adrp + add). It is thus useless to use kern_hyp_va() on it, and actively problematic if kern_hyp_va() becomes non-idempotent. On the other hand, there is no way that the compiler is going to guarantee that such access is always PC relative. So let's bite the bullet and provide our own accessor. Acked-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: James Morse <james.morse@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-12-03 12:28:56 -07:00
/*
* Obtain the PC-relative address of a kernel symbol
* s: symbol
*
* The goal of this macro is to return a symbol's address based on a
* PC-relative computation, as opposed to a loading the VA from a
* constant pool or something similar. This works well for HYP, as an
* absolute VA is guaranteed to be wrong. Only use this if trying to
* obtain the address of a symbol (i.e. not something you obtained by
* following a pointer).
*/
#define hyp_symbol_addr(s) \
({ \
typeof(s) *addr; \
asm("adrp %0, %1\n" \
"add %0, %0, :lo12:%1\n" \
: "=r" (addr) : "S" (&s)); \
addr; \
})
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
/*
arm/arm64: KVM: Fix VTTBR_BADDR_MASK and pgd alloc The current aarch64 calculation for VTTBR_BADDR_MASK masks only 39 bits and not all the bits in the PA range. This is clearly a bug that manifests itself on systems that allocate memory in the higher address space range. [ Modified from Joel's original patch to be based on PHYS_MASK_SHIFT instead of a hard-coded value and to move the alignment check of the allocation to mmu.c. Also added a comment explaining why we hardcode the IPA range and changed the stage-2 pgd allocation to be based on the 40 bit IPA range instead of the maximum possible 48 bit PA range. - Christoffer ] Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Joel Schopp <joel.schopp@amd.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-07-09 10:17:04 -06:00
* We currently only support a 40bit IPA.
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
*/
arm/arm64: KVM: Fix VTTBR_BADDR_MASK and pgd alloc The current aarch64 calculation for VTTBR_BADDR_MASK masks only 39 bits and not all the bits in the PA range. This is clearly a bug that manifests itself on systems that allocate memory in the higher address space range. [ Modified from Joel's original patch to be based on PHYS_MASK_SHIFT instead of a hard-coded value and to move the alignment check of the allocation to mmu.c. Also added a comment explaining why we hardcode the IPA range and changed the stage-2 pgd allocation to be based on the 40 bit IPA range instead of the maximum possible 48 bit PA range. - Christoffer ] Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Joel Schopp <joel.schopp@amd.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-07-09 10:17:04 -06:00
#define KVM_PHYS_SHIFT (40)
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
#define KVM_PHYS_SIZE (1UL << KVM_PHYS_SHIFT)
#define KVM_PHYS_MASK (KVM_PHYS_SIZE - 1UL)
kvm-arm: arm64: Introduce stage2 page table helpers Introduce stage2 page table helpers for arm64. With the fake page table level still in place, the stage2 table has the same number of levels as that of the host (and hyp), so they all fallback to the host version. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
2016-03-22 08:16:52 -06:00
#include <asm/stage2_pgtable.h>
arm/arm64: KVM: Add a protection parameter to create_hyp_mappings Currently, create_hyp_mappings applies a "one size fits all" page protection (PAGE_HYP). As we're heading towards separate protections for different sections, let's make this protection a parameter, and let the callers pass their prefered protection (PAGE_HYP for everyone for the time being). Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2016-06-13 08:00:45 -06:00
int create_hyp_mappings(void *from, void *to, pgprot_t prot);
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
int create_hyp_io_mappings(void *from, void *to, phys_addr_t);
void free_hyp_pgds(void);
arm/arm64: KVM: Introduce stage2_unmap_vm Introduce a new function to unmap user RAM regions in the stage2 page tables. This is needed on reboot (or when the guest turns off the MMU) to ensure we fault in pages again and make the dcache, RAM, and icache coherent. Using unmap_stage2_range for the whole guest physical range does not work, because that unmaps IO regions (such as the GIC) which will not be recreated or in the best case faulted in on a page-by-page basis. Call this function on secondary and subsequent calls to the KVM_ARM_VCPU_INIT ioctl so that a reset VCPU will detect the guest Stage-1 MMU is off when faulting in pages and make the caches coherent. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-11-27 02:35:03 -07:00
void stage2_unmap_vm(struct kvm *kvm);
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
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,
arm/arm64: KVM: add 'writable' parameter to kvm_phys_addr_ioremap Add support for read-only MMIO passthrough mappings by adding a 'writable' parameter to kvm_phys_addr_ioremap. For the moment, mappings will be read-write even if 'writable' is false, but once the definition of PAGE_S2_DEVICE gets changed, those mappings will be created read-only. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-09-17 15:56:18 -06:00
phys_addr_t pa, unsigned long size, bool writable);
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
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)
KVM: ARM: Support hugetlbfs backed huge pages Support huge pages in KVM/ARM and KVM/ARM64. The pud_huge checking on the unmap path may feel a bit silly as the pud_huge check is always defined to false, but the compiler should be smart about this. Note: This deals only with VMAs marked as huge which are allocated by users through hugetlbfs only. Transparent huge pages can only be detected by looking at the underlying pages (or the page tables themselves) and this patch so far simply maps these on a page-by-page level in the Stage-2 page tables. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2012-11-01 10:14:45 -06:00
#define kvm_set_pmd(pmdp, pmd) set_pmd(pmdp, pmd)
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
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)
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
{
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;
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
}
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: ARM: Support hugetlbfs backed huge pages Support huge pages in KVM/ARM and KVM/ARM64. The pud_huge checking on the unmap path may feel a bit silly as the pud_huge check is always defined to false, but the compiler should be smart about this. Note: This deals only with VMAs marked as huge which are allocated by users through hugetlbfs only. Transparent huge pages can only be detected by looking at the underlying pages (or the page tables themselves) and this patch so far simply maps these on a page-by-page level in the Stage-2 page tables. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2012-11-01 10:14:45 -06:00
{
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;
KVM: ARM: Support hugetlbfs backed huge pages Support huge pages in KVM/ARM and KVM/ARM64. The pud_huge checking on the unmap path may feel a bit silly as the pud_huge check is always defined to false, but the compiler should be smart about this. Note: This deals only with VMAs marked as huge which are allocated by users through hugetlbfs only. Transparent huge pages can only be detected by looking at the underlying pages (or the page tables themselves) and this patch so far simply maps these on a page-by-page level in the Stage-2 page tables. Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Russell King <rmk+kernel@arm.linux.org.uk> Acked-by: Catalin Marinas <catalin.marinas@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2012-11-01 10:14:45 -06:00
}
KVM: arm/arm64: Limit icache invalidation to prefetch aborts We've so far eagerly invalidated the icache, no matter how the page was faulted in (data or prefetch abort). But we can easily track execution by setting the XN bits in the S2 page tables, get the prefetch abort at HYP and perform the icache invalidation at that time only. As for most VMs, the instruction working set is pretty small compared to the data set, this is likely to save some traffic (specially as the invalidation is broadcast). Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:19 -06:00
static inline pte_t kvm_s2pte_mkexec(pte_t pte)
{
pte_val(pte) &= ~PTE_S2_XN;
return pte;
}
static inline pmd_t kvm_s2pmd_mkexec(pmd_t pmd)
{
pmd_val(pmd) &= ~PMD_S2_XN;
return pmd;
}
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
static inline void kvm_set_s2pte_readonly(pte_t *ptep)
KVM: arm64: ARMv8 header changes for page logging This patch adds arm64 helpers to write protect pmds/ptes and retrieve permissions while logging dirty pages. Also adds prototype to write protect a memory slot and adds a pmd define to check for read-only pmds. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
2015-01-15 16:58:59 -07:00
{
kvm: arm64: Convert kvm_set_s2pte_readonly() from inline asm to cmpxchg() To take advantage of the LSE atomic instructions and also make the code cleaner, convert the kvm_set_s2pte_readonly() function to use the more generic cmpxchg(). Cc: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-07-06 04:46:39 -06:00
pteval_t old_pteval, pteval;
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
pteval = READ_ONCE(pte_val(*ptep));
kvm: arm64: Convert kvm_set_s2pte_readonly() from inline asm to cmpxchg() To take advantage of the LSE atomic instructions and also make the code cleaner, convert the kvm_set_s2pte_readonly() function to use the more generic cmpxchg(). Cc: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-07-06 04:46:39 -06:00
do {
old_pteval = pteval;
pteval &= ~PTE_S2_RDWR;
pteval |= PTE_S2_RDONLY;
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
pteval = cmpxchg_relaxed(&pte_val(*ptep), old_pteval, pteval);
kvm: arm64: Convert kvm_set_s2pte_readonly() from inline asm to cmpxchg() To take advantage of the LSE atomic instructions and also make the code cleaner, convert the kvm_set_s2pte_readonly() function to use the more generic cmpxchg(). Cc: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Will Deacon <will.deacon@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Acked-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-07-06 04:46:39 -06:00
} while (pteval != old_pteval);
KVM: arm64: ARMv8 header changes for page logging This patch adds arm64 helpers to write protect pmds/ptes and retrieve permissions while logging dirty pages. Also adds prototype to write protect a memory slot and adds a pmd define to check for read-only pmds. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
2015-01-15 16:58:59 -07:00
}
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
static inline bool kvm_s2pte_readonly(pte_t *ptep)
KVM: arm64: ARMv8 header changes for page logging This patch adds arm64 helpers to write protect pmds/ptes and retrieve permissions while logging dirty pages. Also adds prototype to write protect a memory slot and adds a pmd define to check for read-only pmds. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
2015-01-15 16:58:59 -07:00
{
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
return (READ_ONCE(pte_val(*ptep)) & PTE_S2_RDWR) == PTE_S2_RDONLY;
KVM: arm64: ARMv8 header changes for page logging This patch adds arm64 helpers to write protect pmds/ptes and retrieve permissions while logging dirty pages. Also adds prototype to write protect a memory slot and adds a pmd define to check for read-only pmds. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
2015-01-15 16:58:59 -07:00
}
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
static inline bool kvm_s2pte_exec(pte_t *ptep)
KVM: arm/arm64: Preserve Exec permission across R/W permission faults So far, we loose the Exec property whenever we take permission faults, as we always reconstruct the PTE/PMD from scratch. This can be counter productive as we can end-up with the following fault sequence: X -> RO -> ROX -> RW -> RWX Instead, we can lookup the existing PTE/PMD and clear the XN bit in the new entry if it was already cleared in the old one, leadig to a much nicer fault sequence: X -> ROX -> RWX Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:21 -06:00
{
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
return !(READ_ONCE(pte_val(*ptep)) & PTE_S2_XN);
KVM: arm/arm64: Preserve Exec permission across R/W permission faults So far, we loose the Exec property whenever we take permission faults, as we always reconstruct the PTE/PMD from scratch. This can be counter productive as we can end-up with the following fault sequence: X -> RO -> ROX -> RW -> RWX Instead, we can lookup the existing PTE/PMD and clear the XN bit in the new entry if it was already cleared in the old one, leadig to a much nicer fault sequence: X -> ROX -> RWX Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:21 -06:00
}
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
static inline void kvm_set_s2pmd_readonly(pmd_t *pmdp)
KVM: arm64: ARMv8 header changes for page logging This patch adds arm64 helpers to write protect pmds/ptes and retrieve permissions while logging dirty pages. Also adds prototype to write protect a memory slot and adds a pmd define to check for read-only pmds. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
2015-01-15 16:58:59 -07:00
{
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
kvm_set_s2pte_readonly((pte_t *)pmdp);
KVM: arm64: ARMv8 header changes for page logging This patch adds arm64 helpers to write protect pmds/ptes and retrieve permissions while logging dirty pages. Also adds prototype to write protect a memory slot and adds a pmd define to check for read-only pmds. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
2015-01-15 16:58:59 -07:00
}
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
static inline bool kvm_s2pmd_readonly(pmd_t *pmdp)
KVM: arm64: ARMv8 header changes for page logging This patch adds arm64 helpers to write protect pmds/ptes and retrieve permissions while logging dirty pages. Also adds prototype to write protect a memory slot and adds a pmd define to check for read-only pmds. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Mario Smarduch <m.smarduch@samsung.com>
2015-01-15 16:58:59 -07:00
{
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
return kvm_s2pte_readonly((pte_t *)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
}
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
static inline bool kvm_s2pmd_exec(pmd_t *pmdp)
KVM: arm/arm64: Preserve Exec permission across R/W permission faults So far, we loose the Exec property whenever we take permission faults, as we always reconstruct the PTE/PMD from scratch. This can be counter productive as we can end-up with the following fault sequence: X -> RO -> ROX -> RW -> RWX Instead, we can lookup the existing PTE/PMD and clear the XN bit in the new entry if it was already cleared in the old one, leadig to a much nicer fault sequence: X -> ROX -> RWX Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:21 -06:00
{
arm64: mm: Use READ_ONCE/WRITE_ONCE when accessing page tables In many cases, page tables can be accessed concurrently by either another CPU (due to things like fast gup) or by the hardware page table walker itself, which may set access/dirty bits. In such cases, it is important to use READ_ONCE/WRITE_ONCE when accessing page table entries so that entries cannot be torn, merged or subject to apparent loss of coherence due to compiler transformations. Whilst there are some scenarios where this cannot happen (e.g. pinned kernel mappings for the linear region), the overhead of using READ_ONCE /WRITE_ONCE everywhere is minimal and makes the code an awful lot easier to reason about. This patch consistently uses these macros in the arch code, as well as explicitly namespacing pointers to page table entries from the entries themselves by using adopting a 'p' suffix for the former (as is sometimes used elsewhere in the kernel source). Tested-by: Yury Norov <ynorov@caviumnetworks.com> Tested-by: Richard Ruigrok <rruigrok@codeaurora.org> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-02-15 04:14:56 -07:00
return !(READ_ONCE(pmd_val(*pmdp)) & PMD_S2_XN);
KVM: arm/arm64: Preserve Exec permission across R/W permission faults So far, we loose the Exec property whenever we take permission faults, as we always reconstruct the PTE/PMD from scratch. This can be counter productive as we can end-up with the following fault sequence: X -> RO -> ROX -> RW -> RWX Instead, we can lookup the existing PTE/PMD and clear the XN bit in the new entry if it was already cleared in the old one, leadig to a much nicer fault sequence: X -> ROX -> RWX Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:21 -06:00
}
arm/arm64: KVM: Fix and refactor unmap_range unmap_range() was utterly broken, to quote Marc, and broke in all sorts of situations. It was also quite complicated to follow and didn't follow the usual scheme of having a separate iterating function for each level of page tables. Address this by refactoring the code and introduce a pgd_clear() function. Reviewed-by: Jungseok Lee <jays.lee@samsung.com> Reviewed-by: Mario Smarduch <m.smarduch@samsung.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-05-09 15:31:31 -06:00
static inline bool kvm_page_empty(void *ptr)
{
struct page *ptr_page = virt_to_page(ptr);
return page_count(ptr_page) == 1;
}
kvm-arm: arm64: Introduce hyp page table empty checks Introduce hyp_pxx_table_empty helpers for checking whether a given table entry is empty. This will be used explicitly once we switch to explicit routines for hyp page table walk. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
2016-03-22 11:20:28 -06:00
#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
kvm-arm: arm64: Introduce hyp page table empty checks Introduce hyp_pxx_table_empty helpers for checking whether a given table entry is empty. This will be used explicitly once we switch to explicit routines for hyp page table walk. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
2016-03-22 11:20:28 -06:00
#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
kvm-arm: arm64: Introduce hyp page table empty checks Introduce hyp_pxx_table_empty helpers for checking whether a given table entry is empty. This will be used explicitly once we switch to explicit routines for hyp page table walk. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
2016-03-22 11:20:28 -06:00
#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
kvm-arm: arm64: Introduce hyp page table empty checks Introduce hyp_pxx_table_empty helpers for checking whether a given table entry is empty. This will be used explicitly once we switch to explicit routines for hyp page table walk. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
2016-03-22 11:20:28 -06:00
#define hyp_pud_table_empty(pudp) (0)
arm/arm64: KVM: Fix and refactor unmap_range unmap_range() was utterly broken, to quote Marc, and broke in all sorts of situations. It was also quite complicated to follow and didn't follow the usual scheme of having a separate iterating function for each level of page tables. Address this by refactoring the code and introduce a pgd_clear() function. Reviewed-by: Jungseok Lee <jays.lee@samsung.com> Reviewed-by: Mario Smarduch <m.smarduch@samsung.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-05-09 15:31:31 -06:00
#else
kvm-arm: arm64: Introduce hyp page table empty checks Introduce hyp_pxx_table_empty helpers for checking whether a given table entry is empty. This will be used explicitly once we switch to explicit routines for hyp page table walk. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
2016-03-22 11:20:28 -06:00
#define hyp_pud_table_empty(pudp) kvm_page_empty(pudp)
arm/arm64: KVM: Fix and refactor unmap_range unmap_range() was utterly broken, to quote Marc, and broke in all sorts of situations. It was also quite complicated to follow and didn't follow the usual scheme of having a separate iterating function for each level of page tables. Address this by refactoring the code and introduce a pgd_clear() function. Reviewed-by: Jungseok Lee <jays.lee@samsung.com> Reviewed-by: Mario Smarduch <m.smarduch@samsung.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-05-09 15:31:31 -06:00
#endif
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
struct kvm;
arm64: KVM: force cache clean on page fault when caches are off In order for the guest with caches off to observe data written contained in a given page, we need to make sure that page is committed to memory, and not just hanging in the cache (as guest accesses are completely bypassing the cache until it decides to enable it). For this purpose, hook into the coherent_icache_guest_page function and flush the region if the guest SCTLR_EL1 register doesn't show the MMU and caches as being enabled. The function also get renamed to coherent_cache_guest_page. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-01-14 12:13:10 -07:00
#define kvm_flush_dcache_to_poc(a,l) __flush_dcache_area((a), (l))
static inline bool vcpu_has_cache_enabled(struct kvm_vcpu *vcpu)
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
{
KVM: arm64: Rewrite system register accessors to read/write functions Currently we access the system registers array via the vcpu_sys_reg() macro. However, we are about to change the behavior to some times modify the register file directly, so let's change this to two primitives: * Accessor macros vcpu_write_sys_reg() and vcpu_read_sys_reg() * Direct array access macro __vcpu_sys_reg() The accessor macros should be used in places where the code needs to access the currently loaded VCPU's state as observed by the guest. For example, when trapping on cache related registers, a write to a system register should go directly to the VCPU version of the register. The direct array access macro can be used in places where the VCPU is known to never be running (for example userspace access) or for registers which are never context switched (for example all the PMU system registers). This rewrites all users of vcpu_sys_regs to one of the macros described above. No functional change. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Andrew Jones <drjones@redhat.com> Signed-off-by: Christoffer Dall <cdall@cs.columbia.edu> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2016-03-16 08:38:53 -06:00
return (vcpu_read_sys_reg(vcpu, SCTLR_EL1) & 0b101) == 0b101;
arm64: KVM: force cache clean on page fault when caches are off In order for the guest with caches off to observe data written contained in a given page, we need to make sure that page is committed to memory, and not just hanging in the cache (as guest accesses are completely bypassing the cache until it decides to enable it). For this purpose, hook into the coherent_icache_guest_page function and flush the region if the guest SCTLR_EL1 register doesn't show the MMU and caches as being enabled. The function also get renamed to coherent_cache_guest_page. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-01-14 12:13:10 -07:00
}
KVM: arm/arm64: Drop vcpu parameter from guest cache maintenance operartions The vcpu parameter isn't used for anything, and gets in the way of further cleanups. Let's get rid of it. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:22 -06:00
static inline void __clean_dcache_guest_page(kvm_pfn_t pfn, unsigned long size)
arm64: KVM: force cache clean on page fault when caches are off In order for the guest with caches off to observe data written contained in a given page, we need to make sure that page is committed to memory, and not just hanging in the cache (as guest accesses are completely bypassing the cache until it decides to enable it). For this purpose, hook into the coherent_icache_guest_page function and flush the region if the guest SCTLR_EL1 register doesn't show the MMU and caches as being enabled. The function also get renamed to coherent_cache_guest_page. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-01-14 12:13:10 -07:00
{
arm/arm64: KVM: Use kernel mapping to perform invalidation on page fault When handling a fault in stage-2, we need to resync I$ and D$, just to be sure we don't leave any old cache line behind. That's very good, except that we do so using the *user* address. Under heavy load (swapping like crazy), we may end up in a situation where the page gets mapped in stage-2 while being unmapped from userspace by another CPU. At that point, the DC/IC instructions can generate a fault, which we handle with kvm->mmu_lock held. The box quickly deadlocks, user is unhappy. Instead, perform this invalidation through the kernel mapping, which is guaranteed to be present. The box is much happier, and so am I. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2015-01-05 14:13:24 -07:00
void *va = page_address(pfn_to_page(pfn));
arm/arm64: KVM: Enforce unconditional flush to PoC when mapping to stage-2 When we fault in a page, we flush it to the PoC (Point of Coherency) if the faulting vcpu has its own caches off, so that it can observe the page we just brought it. But if the vcpu has its caches on, we skip that step. Bad things happen when *another* vcpu tries to access that page with its own caches disabled. At that point, there is no garantee that the data has made it to the PoC, and we access stale data. The obvious fix is to always flush to PoC when a page is faulted in, no matter what the state of the vcpu is. Cc: stable@vger.kernel.org Fixes: 2d58b733c876 ("arm64: KVM: force cache clean on page fault when caches are off") Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2017-01-25 05:29:59 -07:00
kvm_flush_dcache_to_poc(va, size);
KVM: arm/arm64: Split dcache/icache flushing As we're about to introduce opportunistic invalidation of the icache, let's split dcache and icache flushing. Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:15 -06:00
}
arm64: KVM: force cache clean on page fault when caches are off In order for the guest with caches off to observe data written contained in a given page, we need to make sure that page is committed to memory, and not just hanging in the cache (as guest accesses are completely bypassing the cache until it decides to enable it). For this purpose, hook into the coherent_icache_guest_page function and flush the region if the guest SCTLR_EL1 register doesn't show the MMU and caches as being enabled. The function also get renamed to coherent_cache_guest_page. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-01-14 12:13:10 -07:00
KVM: arm/arm64: Drop vcpu parameter from guest cache maintenance operartions The vcpu parameter isn't used for anything, and gets in the way of further cleanups. Let's get rid of it. Acked-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:22 -06:00
static inline void __invalidate_icache_guest_page(kvm_pfn_t pfn,
KVM: arm/arm64: Split dcache/icache flushing As we're about to introduce opportunistic invalidation of the icache, let's split dcache and icache flushing. Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:15 -06:00
unsigned long size)
{
arm64: KVM: Add support for VPIPT I-caches A VPIPT I-cache has two main properties: 1. Lines allocated into the cache are tagged by VMID and a lookup can only hit lines that were allocated with the current VMID. 2. I-cache invalidation from EL1/0 only invalidates lines that match the current VMID of the CPU doing the invalidation. This can cause issues with non-VHE configurations, where the host runs at EL1 and wants to invalidate I-cache entries for a guest running with a different VMID. VHE is not affected, because the host runs at EL2 and I-cache invalidation applies as expected. This patch solves the problem by invalidating the I-cache when unmapping a page at stage 2 on a system with a VPIPT I-cache but not running with VHE enabled. Hopefully this is an obscure enough configuration that the overhead isn't anything to worry about, although it does mean that the by-range I-cache invalidation currently performed when mapping at stage 2 can be elided on such systems, because the I-cache will be clean for the guest VMID following a rollover event. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-10 13:32:25 -07:00
if (icache_is_aliasing()) {
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
/* any kind of VIPT cache */
__flush_icache_all();
arm64: KVM: Add support for VPIPT I-caches A VPIPT I-cache has two main properties: 1. Lines allocated into the cache are tagged by VMID and a lookup can only hit lines that were allocated with the current VMID. 2. I-cache invalidation from EL1/0 only invalidates lines that match the current VMID of the CPU doing the invalidation. This can cause issues with non-VHE configurations, where the host runs at EL1 and wants to invalidate I-cache entries for a guest running with a different VMID. VHE is not affected, because the host runs at EL2 and I-cache invalidation applies as expected. This patch solves the problem by invalidating the I-cache when unmapping a page at stage 2 on a system with a VPIPT I-cache but not running with VHE enabled. Hopefully this is an obscure enough configuration that the overhead isn't anything to worry about, although it does mean that the by-range I-cache invalidation currently performed when mapping at stage 2 can be elided on such systems, because the I-cache will be clean for the guest VMID following a rollover event. Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-10 13:32:25 -07:00
} else if (is_kernel_in_hyp_mode() || !icache_is_vpipt()) {
/* PIPT or VPIPT at EL2 (see comment in __kvm_tlb_flush_vmid_ipa) */
KVM: arm/arm64: Split dcache/icache flushing As we're about to introduce opportunistic invalidation of the icache, let's split dcache and icache flushing. Acked-by: Christoffer Dall <cdall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:15 -06:00
void *va = page_address(pfn_to_page(pfn));
arm64: KVM: Add invalidate_icache_range helper We currently tightly couple dcache clean with icache invalidation, but KVM could do without the initial flush to PoU, as we've already flushed things to PoC. Let's introduce invalidate_icache_range which is limited to invalidating the icache from the linear mapping (and thus has none of the userspace fault handling complexity), and wire it in KVM instead of flush_icache_range. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2017-10-23 10:11:16 -06:00
invalidate_icache_range((unsigned long)va,
(unsigned long)va + size);
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
}
}
arm/arm64: KVM: Invalidate data cache on unmap Let's assume a guest has created an uncached mapping, and written to that page. Let's also assume that the host uses a cache-coherent IO subsystem. Let's finally assume that the host is under memory pressure and starts to swap things out. Before this "uncached" page is evicted, we need to make sure we invalidate potential speculated, clean cache lines that are sitting there, or the IO subsystem is going to swap out the cached view, loosing the data that has been written directly into memory. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-19 09:48:06 -07:00
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);
}
arm64: Use __pa_symbol for kernel symbols __pa_symbol is technically the marcro that should be used for kernel symbols. Switch to this as a pre-requisite for DEBUG_VIRTUAL which will do bounds checking. Reviewed-by: Mark Rutland <mark.rutland@arm.com> Tested-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Laura Abbott <labbott@redhat.com> Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-01-10 14:35:49 -07:00
#define kvm_virt_to_phys(x) __pa_symbol(x)
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
arm/arm64: KVM: Use set/way op trapping to track the state of the caches Trying to emulate the behaviour of set/way cache ops is fairly pointless, as there are too many ways we can end-up missing stuff. Also, there is some system caches out there that simply ignore set/way operations. So instead of trying to implement them, let's convert it to VA ops, and use them as a way to re-enable the trapping of VM ops. That way, we can detect the point when the MMU/caches are turned off, and do a full VM flush (which is what the guest was trying to do anyway). This allows a 32bit zImage to boot on the APM thingy, and will probably help bootloaders in general. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-12-19 09:05:31 -07:00
void kvm_set_way_flush(struct kvm_vcpu *vcpu);
void kvm_toggle_cache(struct kvm_vcpu *vcpu, bool was_enabled);
arm64: KVM: flush VM pages before letting the guest enable caches When the guest runs with caches disabled (like in an early boot sequence, for example), all the writes are diectly going to RAM, bypassing the caches altogether. Once the MMU and caches are enabled, whatever sits in the cache becomes suddenly visible, which isn't what the guest expects. A way to avoid this potential disaster is to invalidate the cache when the MMU is being turned on. For this, we hook into the SCTLR_EL1 trapping code, and scan the stage-2 page tables, invalidating the pages/sections that have already been mapped in. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
2014-01-15 05:50:23 -07:00
arm64: KVM: use ID map with increased VA range if required This patch modifies the HYP init code so it can deal with system RAM residing at an offset which exceeds the reach of VA_BITS. Like for EL1, this involves configuring an additional level of translation for the ID map. However, in case of EL2, this implies that all translations use the extra level, as we cannot seamlessly switch between translation tables with different numbers of translation levels. So add an extra translation table at the root level. Since the ID map and the runtime HYP map are guaranteed not to overlap, they can share this root level, and we can essentially merge these two tables into one. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-19 10:42:28 -06:00
static inline bool __kvm_cpu_uses_extended_idmap(void)
{
arm64: allow ID map to be extended to 52 bits Currently, when using VA_BITS < 48, if the ID map text happens to be placed in physical memory above VA_BITS, we increase the VA size (up to 48) and create a new table level, in order to map in the ID map text. This is okay because the system always supports 48 bits of VA. This patch extends the code such that if the system supports 52 bits of VA, and the ID map text is placed that high up, then we increase the VA size accordingly, up to 52. One difference from the current implementation is that so far the condition of VA_BITS < 48 has meant that the top level table is always "full", with the maximum number of entries, and an extra table level is always needed. Now, when VA_BITS = 48 (and using 64k pages), the top level table is not full, and we simply need to increase the number of entries in it, instead of creating a new table level. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: reduce arguments to __create_hyp_mappings()] [catalin.marinas@arm.com: reworked/renamed __cpu_uses_extended_idmap_level()] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-13 10:07:24 -07:00
return __cpu_uses_extended_idmap_level();
}
static inline unsigned long __kvm_idmap_ptrs_per_pgd(void)
{
return idmap_ptrs_per_pgd;
arm64: KVM: use ID map with increased VA range if required This patch modifies the HYP init code so it can deal with system RAM residing at an offset which exceeds the reach of VA_BITS. Like for EL1, this involves configuring an additional level of translation for the ID map. However, in case of EL2, this implies that all translations use the extra level, as we cannot seamlessly switch between translation tables with different numbers of translation levels. So add an extra translation table at the root level. Since the ID map and the runtime HYP map are guaranteed not to overlap, they can share this root level, and we can essentially merge these two tables into one. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-19 10:42:28 -06:00
}
arm64: don't open code page table entry creation Instead of open coding the generation of page table entries, use the macros/functions that exist for this - pfn_p*d and p*d_populate. Most code in the kernel already uses these macros, this patch tries to fix up the few places that don't. This is useful for the next patch in this series, which needs to change the page table entry logic, and it's better to have that logic in one place. The KVM extended ID map is special, since we're creating a level above CONFIG_PGTABLE_LEVELS and the required function isn't available. Leave it as is and add a comment to explain it. (The normal kernel ID map code doesn't need this change because its page tables are created in assembly (__create_page_tables)). Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-13 10:07:20 -07:00
/*
* Can't use pgd_populate here, because the extended idmap adds an extra level
* above CONFIG_PGTABLE_LEVELS (which is 2 or 3 if we're using the extended
* idmap), and pgd_populate is only available if CONFIG_PGTABLE_LEVELS = 4.
*/
arm64: KVM: use ID map with increased VA range if required This patch modifies the HYP init code so it can deal with system RAM residing at an offset which exceeds the reach of VA_BITS. Like for EL1, this involves configuring an additional level of translation for the ID map. However, in case of EL2, this implies that all translations use the extra level, as we cannot seamlessly switch between translation tables with different numbers of translation levels. So add an extra translation table at the root level. Since the ID map and the runtime HYP map are guaranteed not to overlap, they can share this root level, and we can essentially merge these two tables into one. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-19 10:42:28 -06:00
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;
arm64: handle 52-bit physical addresses in page table entries The top 4 bits of a 52-bit physical address are positioned at bits 12..15 of a page table entry. Introduce macros to convert between a physical address and its placement in a table entry, and change all macros/functions that access PTEs to use them. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: some long lines wrapped] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-13 10:07:21 -07:00
u64 pgd_addr;
arm64: KVM: use ID map with increased VA range if required This patch modifies the HYP init code so it can deal with system RAM residing at an offset which exceeds the reach of VA_BITS. Like for EL1, this involves configuring an additional level of translation for the ID map. However, in case of EL2, this implies that all translations use the extra level, as we cannot seamlessly switch between translation tables with different numbers of translation levels. So add an extra translation table at the root level. Since the ID map and the runtime HYP map are guaranteed not to overlap, they can share this root level, and we can essentially merge these two tables into one. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-19 10:42:28 -06:00
/*
* 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]));
arm64: handle 52-bit physical addresses in page table entries The top 4 bits of a 52-bit physical address are positioned at bits 12..15 of a page table entry. Introduce macros to convert between a physical address and its placement in a table entry, and change all macros/functions that access PTEs to use them. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: some long lines wrapped] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-13 10:07:21 -07:00
pgd_addr = __phys_to_pgd_val(__pa(hyp_pgd));
merged_hyp_pgd[0] = __pgd(pgd_addr | PMD_TYPE_TABLE);
arm64: KVM: use ID map with increased VA range if required This patch modifies the HYP init code so it can deal with system RAM residing at an offset which exceeds the reach of VA_BITS. Like for EL1, this involves configuring an additional level of translation for the ID map. However, in case of EL2, this implies that all translations use the extra level, as we cannot seamlessly switch between translation tables with different numbers of translation levels. So add an extra translation table at the root level. Since the ID map and the runtime HYP map are guaranteed not to overlap, they can share this root level, and we can essentially merge these two tables into one. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-19 10:42:28 -06:00
/*
* 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]));
arm64: handle 52-bit physical addresses in page table entries The top 4 bits of a 52-bit physical address are positioned at bits 12..15 of a page table entry. Introduce macros to convert between a physical address and its placement in a table entry, and change all macros/functions that access PTEs to use them. Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: some long lines wrapped] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-13 10:07:21 -07:00
pgd_addr = __phys_to_pgd_val(__pa(boot_hyp_pgd));
merged_hyp_pgd[idmap_idx] = __pgd(pgd_addr | PMD_TYPE_TABLE);
arm64: KVM: use ID map with increased VA range if required This patch modifies the HYP init code so it can deal with system RAM residing at an offset which exceeds the reach of VA_BITS. Like for EL1, this involves configuring an additional level of translation for the ID map. However, in case of EL2, this implies that all translations use the extra level, as we cannot seamlessly switch between translation tables with different numbers of translation levels. So add an extra translation table at the root level. Since the ID map and the runtime HYP map are guaranteed not to overlap, they can share this root level, and we can essentially merge these two tables into one. Tested-by: Marc Zyngier <marc.zyngier@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Ard Biesheuvel <ard.biesheuvel@linaro.org> Signed-off-by: Will Deacon <will.deacon@arm.com>
2015-03-19 10:42:28 -06:00
}
arm64: KVM: Add support for 16-bit VMID The ARMv8.1 architecture extension allows to choose between 8-bit and 16-bit of VMID, so use this capability for KVM. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-11-16 04:28:18 -07:00
static inline unsigned int kvm_get_vmid_bits(void)
{
arm64: cpufeature: Make ID reg accessor naming less counterintuitive read_system_reg() can readily be confused with read_sysreg(), whereas these are really quite different in their meaning. This patches attempts to reduce the ambiguity be reserving "sysreg" for the actual system register accessors. read_system_reg() is instead renamed to read_sanitised_ftr_reg(), to make it more obvious that the Linux-defined sanitised feature register cache is being accessed here, not the underlying architectural system registers. cpufeature.c's internal __raw_read_system_reg() function is renamed in line with its actual purpose: a form of read_sysreg() that indexes on (non-compiletime-constant) encoding rather than symbolic register name. Acked-by: Mark Rutland <mark.rutland@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Signed-off-by: Dave Martin <Dave.Martin@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-03-23 09:14:39 -06:00
int reg = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);
arm64: KVM: Add support for 16-bit VMID The ARMv8.1 architecture extension allows to choose between 8-bit and 16-bit of VMID, so use this capability for KVM. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-11-16 04:28:18 -07:00
arm64: Rename cpuid_feature field extract routines Now that we have a clear understanding of the sign of a feature, rename the routines to reflect the sign, so that it is not misused. The cpuid_feature_extract_field() now accepts a 'sign' parameter. Signed-off-by: Suzuki K. Poulose <suzuki.poulose@arm.com> Acked-by: Will Deacon <will.deacon@arm.com> Acked-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2016-01-26 03:58:16 -07:00
return (cpuid_feature_extract_unsigned_field(reg, ID_AA64MMFR1_VMIDBITS_SHIFT) == 2) ? 16 : 8;
arm64: KVM: Add support for 16-bit VMID The ARMv8.1 architecture extension allows to choose between 8-bit and 16-bit of VMID, so use this capability for KVM. Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org> Signed-off-by: Vladimir Murzin <vladimir.murzin@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2015-11-16 04:28:18 -07:00
}
arm64: KVM: Use per-CPU vector when BP hardening is enabled Now that we have per-CPU vectors, let's plug then in the KVM/arm64 code. Signed-off-by: Marc Zyngier <marc.zyngier@arm.com> Signed-off-by: Will Deacon <will.deacon@arm.com> Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2018-01-03 09:38:35 -07:00
#ifdef CONFIG_HARDEN_BRANCH_PREDICTOR
#include <asm/mmu.h>
static inline void *kvm_get_hyp_vector(void)
{
struct bp_hardening_data *data = arm64_get_bp_hardening_data();
void *vect = kvm_ksym_ref(__kvm_hyp_vector);
if (data->fn) {
vect = __bp_harden_hyp_vecs_start +
data->hyp_vectors_slot * SZ_2K;
if (!has_vhe())
vect = lm_alias(vect);
}
return vect;
}
static inline int kvm_map_vectors(void)
{
return create_hyp_mappings(kvm_ksym_ref(__bp_harden_hyp_vecs_start),
kvm_ksym_ref(__bp_harden_hyp_vecs_end),
PAGE_HYP_EXEC);
}
#else
static inline void *kvm_get_hyp_vector(void)
{
return kvm_ksym_ref(__kvm_hyp_vector);
}
static inline int kvm_map_vectors(void)
{
return 0;
}
#endif
arm64: handle 52-bit addresses in TTBR The top 4 bits of a 52-bit physical address are positioned at bits 2..5 in the TTBR registers. Introduce a couple of macros to move the bits there, and change all TTBR writers to use them. Leave TTBR0 PAN code unchanged, to avoid complicating it. A system with 52-bit PA will have PAN anyway (because it's ARMv8.1 or later), and a system without 52-bit PA can only use up to 48-bit PAs. A later patch in this series will add a kconfig dependency to ensure PAN is configured. In addition, when using 52-bit PA there is a special alignment requirement on the top-level table. We don't currently have any VA_BITS configuration that would violate the requirement, but one could be added in the future, so add a compile-time BUG_ON to check for it. Tested-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Marc Zyngier <marc.zyngier@arm.com> Tested-by: Bob Picco <bob.picco@oracle.com> Reviewed-by: Bob Picco <bob.picco@oracle.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> [catalin.marinas@arm.com: added TTBR_BADD_MASK_52 comment] Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2017-12-13 10:07:18 -07:00
#define kvm_phys_to_vttbr(addr) phys_to_ttbr(addr)
arm64: KVM: architecture specific MMU backend Define the arm64 specific MMU backend: - HYP/kernel VA offset - S2 4/64kB definitions - S2 page table populating and flushing - icache cleaning Reviewed-by: Christopher Covington <cov@codeaurora.org> Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
2012-12-10 08:35:24 -07:00
#endif /* __ASSEMBLY__ */
#endif /* __ARM64_KVM_MMU_H__ */