| Message ID | 20230201125328.2186498-10-jean-philippe@linaro.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | KVM: Arm SMMUv3 driver for pKVM | expand |
Hi Jean, On Wed, Feb 01, 2023 at 12:52:53PM +0000, Jean-Philippe Brucker wrote: > Add a function to map a MMIO region in the hypervisor and remove it from > the host. Hypervisor device drivers use this to reserve their regions > during setup. > > Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> > --- > arch/arm64/kvm/hyp/include/nvhe/mm.h | 1 + > arch/arm64/kvm/hyp/nvhe/setup.c | 17 +++++++++++++++++ > 2 files changed, 18 insertions(+) > > diff --git a/arch/arm64/kvm/hyp/include/nvhe/mm.h b/arch/arm64/kvm/hyp/include/nvhe/mm.h > index d5ec972b5c1e..84db840f2057 100644 > --- a/arch/arm64/kvm/hyp/include/nvhe/mm.h > +++ b/arch/arm64/kvm/hyp/include/nvhe/mm.h > @@ -27,5 +27,6 @@ int __pkvm_create_private_mapping(phys_addr_t phys, size_t size, > enum kvm_pgtable_prot prot, > unsigned long *haddr); > int pkvm_alloc_private_va_range(size_t size, unsigned long *haddr); > +int pkvm_create_hyp_device_mapping(u64 base, u64 size, void __iomem *haddr); > > #endif /* __KVM_HYP_MM_H */ > diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c > index 629e74c46b35..de7d60c3c20b 100644 > --- a/arch/arm64/kvm/hyp/nvhe/setup.c > +++ b/arch/arm64/kvm/hyp/nvhe/setup.c > @@ -259,6 +259,23 @@ static int fix_host_ownership(void) > return 0; > } > > +/* Map the MMIO region into the hypervisor and remove it from host */ > +int pkvm_create_hyp_device_mapping(u64 base, u64 size, void __iomem *haddr) > +{ > + int ret; > + > + ret = __pkvm_create_private_mapping(base, size, PAGE_HYP_DEVICE, haddr); > + if (ret) > + return ret; > + > + /* lock not needed during setup */ > + ret = host_stage2_set_owner_locked(base, size, PKVM_ID_HYP); > + if (ret) > + return ret; > + Do we need to unmap in case of errors from host_stage2_set_owner_locked? > + return ret; > +} > + > static int fix_hyp_pgtable_refcnt(void) > { > struct kvm_pgtable_walker walker = { > -- > 2.39.0 >
On Tue, Feb 07, 2023 at 12:22:13PM +0000, Mostafa Saleh wrote: > > +/* Map the MMIO region into the hypervisor and remove it from host */ > > +int pkvm_create_hyp_device_mapping(u64 base, u64 size, void __iomem *haddr) > > +{ > > + int ret; > > + > > + ret = __pkvm_create_private_mapping(base, size, PAGE_HYP_DEVICE, haddr); > > + if (ret) > > + return ret; > > + > > + /* lock not needed during setup */ > > + ret = host_stage2_set_owner_locked(base, size, PKVM_ID_HYP); > > + if (ret) > > + return ret; > > + > > Do we need to unmap in case of errors from host_stage2_set_owner_locked? I don't think so because this function is meant for hyp setup only, so any error causes a complete teardown of both hyp and host page tables I wondered about adding a BUG_ON() here if the function is not used during setup, but maybe improving the comment would be good enough. Thanks, Jean
diff --git a/arch/arm64/kvm/hyp/include/nvhe/mm.h b/arch/arm64/kvm/hyp/include/nvhe/mm.h index d5ec972b5c1e..84db840f2057 100644 --- a/arch/arm64/kvm/hyp/include/nvhe/mm.h +++ b/arch/arm64/kvm/hyp/include/nvhe/mm.h @@ -27,5 +27,6 @@ int __pkvm_create_private_mapping(phys_addr_t phys, size_t size, enum kvm_pgtable_prot prot, unsigned long *haddr); int pkvm_alloc_private_va_range(size_t size, unsigned long *haddr); +int pkvm_create_hyp_device_mapping(u64 base, u64 size, void __iomem *haddr); #endif /* __KVM_HYP_MM_H */ diff --git a/arch/arm64/kvm/hyp/nvhe/setup.c b/arch/arm64/kvm/hyp/nvhe/setup.c index 629e74c46b35..de7d60c3c20b 100644 --- a/arch/arm64/kvm/hyp/nvhe/setup.c +++ b/arch/arm64/kvm/hyp/nvhe/setup.c @@ -259,6 +259,23 @@ static int fix_host_ownership(void) return 0; } +/* Map the MMIO region into the hypervisor and remove it from host */ +int pkvm_create_hyp_device_mapping(u64 base, u64 size, void __iomem *haddr) +{ + int ret; + + ret = __pkvm_create_private_mapping(base, size, PAGE_HYP_DEVICE, haddr); + if (ret) + return ret; + + /* lock not needed during setup */ + ret = host_stage2_set_owner_locked(base, size, PKVM_ID_HYP); + if (ret) + return ret; + + return ret; +} + static int fix_hyp_pgtable_refcnt(void) { struct kvm_pgtable_walker walker = {
Add a function to map a MMIO region in the hypervisor and remove it from the host. Hypervisor device drivers use this to reserve their regions during setup. Signed-off-by: Jean-Philippe Brucker <jean-philippe@linaro.org> --- arch/arm64/kvm/hyp/include/nvhe/mm.h | 1 + arch/arm64/kvm/hyp/nvhe/setup.c | 17 +++++++++++++++++ 2 files changed, 18 insertions(+)