lkml.org 
[lkml]   [2020]   [Nov]   [11]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v1 16/24] kvm: arm64: Add offset for hyp VA <-> PA conversion
On 2020-11-09 11:32, David Brazdil wrote:
> Add a host-initialized constant to KVM nVHE hyp code for converting
> between EL2 linear map virtual addresses and physical addresses.
> Also add `__hyp_pa` macro that performs the conversion.
>
> Signed-off-by: David Brazdil <dbrazdil@google.com>
> ---
> arch/arm64/kvm/arm.c | 15 +++++++++++++++
> arch/arm64/kvm/hyp/nvhe/psci.c | 3 +++
> 2 files changed, 18 insertions(+)
>
> diff --git a/arch/arm64/kvm/arm.c b/arch/arm64/kvm/arm.c
> index 28e3bc056225..dc7d43d7785a 100644
> --- a/arch/arm64/kvm/arm.c
> +++ b/arch/arm64/kvm/arm.c
> @@ -1484,6 +1484,20 @@ static inline void hyp_cpu_pm_exit(void)
> }
> #endif
>
> +static void init_hyp_physvirt_offset(void)
> +{
> + extern s64 kvm_nvhe_sym(hyp_physvirt_offset);
> + unsigned long kern_vaddr, hyp_vaddr, paddr;
> +
> + /* Check that kvm_arm_hyp_percpu_base has been set. */
> + BUG_ON(kvm_arm_hyp_percpu_base[0] == 0);

Why is this dependent on the percpu base? Or is that just a convenient
symbol?

> +
> + kern_vaddr = kvm_arm_hyp_percpu_base[0];
> + hyp_vaddr = kern_hyp_va(kern_vaddr);
> + paddr = __pa(kern_vaddr);
> + CHOOSE_NVHE_SYM(hyp_physvirt_offset) = (s64)paddr - (s64)hyp_vaddr;
> +}

It feels like this offset could be set at the point where we compute
the hyp_va offset in va_layout.c, couldn't it? It would have the
advantage of keeping all the ugly VA hacks together.

> +
> static void init_cpu_logical_map(void)
> {
> extern u64 kvm_nvhe_sym(__cpu_logical_map)[NR_CPUS];
> @@ -1688,6 +1702,7 @@ static int init_hyp_mode(void)
> }
> }
>
> + init_hyp_physvirt_offset();
> init_cpu_logical_map();
> init_psci();
>
> diff --git a/arch/arm64/kvm/hyp/nvhe/psci.c
> b/arch/arm64/kvm/hyp/nvhe/psci.c
> index 82d3b2c89658..b0b5df590ba5 100644
> --- a/arch/arm64/kvm/hyp/nvhe/psci.c
> +++ b/arch/arm64/kvm/hyp/nvhe/psci.c
> @@ -16,6 +16,9 @@
> /* Config options set by the host. */
> u32 kvm_host_psci_version = PSCI_VERSION(0, 0);
> u32 kvm_host_psci_function_id[PSCI_FN_MAX];
> +s64 hyp_physvirt_offset;
> +
> +#define __hyp_pa(x) ((phys_addr_t)((x)) + hyp_physvirt_offset)
>
> static u64 get_psci_func_id(struct kvm_cpu_context *host_ctxt)
> {

Thanks,

M.
--
Jazz is not dead. It just smells funny...

\
 
 \ /
  Last update: 2020-11-11 14:49    [W:0.315 / U:1.300 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site