diff options
| author | Quentin Perret <qperret@google.com> | 2021-08-09 18:24:38 +0300 |
|---|---|---|
| committer | Marc Zyngier <maz@kernel.org> | 2021-08-11 13:39:50 +0300 |
| commit | 4505e9b624cefafa4b75d8a28e72f32076c33375 (patch) | |
| tree | ec067052718c4822c0029404a814a468380f943a /arch/arm64/include/asm/kvm_pgtable.h | |
| parent | 5651311941105ca077d3ab74dd4a92e646ecf7fb (diff) | |
| download | linux-4505e9b624cefafa4b75d8a28e72f32076c33375.tar.xz | |
KVM: arm64: Allow populating software bits
Introduce infrastructure allowing to manipulate software bits in stage-1
and stage-2 page-tables using additional entries in the kvm_pgtable_prot
enum.
This is heavily inspired by Marc's implementation of a similar feature
in the NV patch series, but adapted to allow stage-1 changes as well:
https://lore.kernel.org/kvmarm/20210510165920.1913477-56-maz@kernel.org/
Suggested-by: Marc Zyngier <maz@kernel.org>
Signed-off-by: Quentin Perret <qperret@google.com>
Reviewed-by: Fuad Tabba <tabba@google.com>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20210809152448.1810400-12-qperret@google.com
Diffstat (limited to 'arch/arm64/include/asm/kvm_pgtable.h')
| -rw-r--r-- | arch/arm64/include/asm/kvm_pgtable.h | 12 |
1 files changed, 11 insertions, 1 deletions
diff --git a/arch/arm64/include/asm/kvm_pgtable.h b/arch/arm64/include/asm/kvm_pgtable.h index ca0c039547b5..bfea573703d7 100644 --- a/arch/arm64/include/asm/kvm_pgtable.h +++ b/arch/arm64/include/asm/kvm_pgtable.h @@ -121,6 +121,10 @@ enum kvm_pgtable_stage2_flags { * @KVM_PGTABLE_PROT_W: Write permission. * @KVM_PGTABLE_PROT_R: Read permission. * @KVM_PGTABLE_PROT_DEVICE: Device attributes. + * @KVM_PGTABLE_PROT_SW0: Software bit 0. + * @KVM_PGTABLE_PROT_SW1: Software bit 1. + * @KVM_PGTABLE_PROT_SW2: Software bit 2. + * @KVM_PGTABLE_PROT_SW3: Software bit 3. */ enum kvm_pgtable_prot { KVM_PGTABLE_PROT_X = BIT(0), @@ -128,6 +132,11 @@ enum kvm_pgtable_prot { KVM_PGTABLE_PROT_R = BIT(2), KVM_PGTABLE_PROT_DEVICE = BIT(3), + + KVM_PGTABLE_PROT_SW0 = BIT(55), + KVM_PGTABLE_PROT_SW1 = BIT(56), + KVM_PGTABLE_PROT_SW2 = BIT(57), + KVM_PGTABLE_PROT_SW3 = BIT(58), }; #define KVM_PGTABLE_PROT_RW (KVM_PGTABLE_PROT_R | KVM_PGTABLE_PROT_W) @@ -420,7 +429,8 @@ kvm_pte_t kvm_pgtable_stage2_mkold(struct kvm_pgtable *pgt, u64 addr); * If there is a valid, leaf page-table entry used to translate @addr, then * relax the permissions in that entry according to the read, write and * execute permissions specified by @prot. No permissions are removed, and - * TLB invalidation is performed after updating the entry. + * TLB invalidation is performed after updating the entry. Software bits cannot + * be set or cleared using kvm_pgtable_stage2_relax_perms(). * * Return: 0 on success, negative error code on failure. */ |