| Message ID | 20210729132818.4091769-13-qperret@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Track shared pages at EL2 in protected mode | expand |
Hi Quentin, On Thu, Jul 29, 2021 at 3:28 PM Quentin Perret <qperret@google.com> wrote: > > We will soon start annotating shared pages in page-tables in nVHE > protected mode. Define all the states in which a page can be (owned, > shared and owned, shared and borrowed), and provide helpers allowing to > convert this into SW bits annotations using the matching prot > attributes. > > Signed-off-by: Quentin Perret <qperret@google.com> > --- > arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 26 +++++++++++++++++++ > 1 file changed, 26 insertions(+) > > diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h > index 9c227d87c36d..ae355bfd8c01 100644 > --- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h > +++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h > @@ -12,6 +12,32 @@ > #include <asm/virt.h> > #include <nvhe/spinlock.h> > > +/* > + * SW bits 0-1 are reserved to track the memory ownership state of each page: > + * 00: The page is owned solely by the page-table owner. nit: solely -> exclusively, because "exclusive" is the more common term in context of shared resources > + * 01: The page is owned by the page-table owner, but is shared > + * with another entity. > + * 10: The page is shared with, but not owned by the page-table owner. > + * 11: Reserved for future use (lending). > + */ > +enum pkvm_page_state { > + PKVM_PAGE_OWNED = 0ULL, > + PKVM_PAGE_SHARED_OWNED = KVM_PGTABLE_PROT_SW0, > + PKVM_PAGE_SHARED_BORROWED = KVM_PGTABLE_PROT_SW1, > +}; > + > +#define PKVM_PAGE_STATE_PROT_MASK (KVM_PGTABLE_PROT_SW0 | KVM_PGTABLE_PROT_SW1) > +static inline enum kvm_pgtable_prot pkvm_mkstate(enum kvm_pgtable_prot prot, > + enum pkvm_page_state state) > +{ > + return (prot & ~PKVM_PAGE_STATE_PROT_MASK) | state; > +} > + > +static inline enum pkvm_page_state pkvm_getstate(enum kvm_pgtable_prot prot) > +{ > + return prot & PKVM_PAGE_STATE_PROT_MASK; > +} > + I think that this encoding is pretty neat and easy to follow. Reviewed-by: Fuad Tabba <tabba@google.com> Thanks, /fuad > struct host_kvm { > struct kvm_arch arch; > struct kvm_pgtable pgt; > -- > 2.32.0.432.gabb21c7263-goog >
diff --git a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h index 9c227d87c36d..ae355bfd8c01 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h +++ b/arch/arm64/kvm/hyp/include/nvhe/mem_protect.h @@ -12,6 +12,32 @@ #include <asm/virt.h> #include <nvhe/spinlock.h> +/* + * SW bits 0-1 are reserved to track the memory ownership state of each page: + * 00: The page is owned solely by the page-table owner. + * 01: The page is owned by the page-table owner, but is shared + * with another entity. + * 10: The page is shared with, but not owned by the page-table owner. + * 11: Reserved for future use (lending). + */ +enum pkvm_page_state { + PKVM_PAGE_OWNED = 0ULL, + PKVM_PAGE_SHARED_OWNED = KVM_PGTABLE_PROT_SW0, + PKVM_PAGE_SHARED_BORROWED = KVM_PGTABLE_PROT_SW1, +}; + +#define PKVM_PAGE_STATE_PROT_MASK (KVM_PGTABLE_PROT_SW0 | KVM_PGTABLE_PROT_SW1) +static inline enum kvm_pgtable_prot pkvm_mkstate(enum kvm_pgtable_prot prot, + enum pkvm_page_state state) +{ + return (prot & ~PKVM_PAGE_STATE_PROT_MASK) | state; +} + +static inline enum pkvm_page_state pkvm_getstate(enum kvm_pgtable_prot prot) +{ + return prot & PKVM_PAGE_STATE_PROT_MASK; +} + struct host_kvm { struct kvm_arch arch; struct kvm_pgtable pgt;
We will soon start annotating shared pages in page-tables in nVHE protected mode. Define all the states in which a page can be (owned, shared and owned, shared and borrowed), and provide helpers allowing to convert this into SW bits annotations using the matching prot attributes. Signed-off-by: Quentin Perret <qperret@google.com> --- arch/arm64/kvm/hyp/include/nvhe/mem_protect.h | 26 +++++++++++++++++++ 1 file changed, 26 insertions(+)