Re: [PATCH V3 07/30] x86/sgx: Rename sgx_encl_ewb_cpumask() as sgx_encl_cpumask()

Jarkko Sakkinen
2022-04-05T06:56:10Z

On Mon, Apr 04, 2022 at 09:49:15AM -0700, Reinette Chatre wrote:
> sgx_encl_ewb_cpumask() is no longer unique to the reclaimer where it
> is used during the EWB ENCLS leaf function when EPC pages are written
> out to main memory and sgx_encl_ewb_cpumask() is used to learn which
> CPUs might have executed the enclave to ensure that TLBs are cleared.
>
> Upcoming SGX2 enabling will use sgx_encl_ewb_cpumask() during the
> EMODPR and EMODT ENCLS leaf functions that make changes to enclave
> pages. The function is needed for the same reason it is used now: to
> learn which CPUs might have executed the enclave to ensure that TLBs
> no longer point to the changed pages.
>
> Rename sgx_encl_ewb_cpumask() to sgx_encl_cpumask() to reflect the
> broader usage.
>
> Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
> ---
> No changes since V2
>
> Changes since V1:
> - New patch split from original "x86/sgx: Use more generic name for
> enclave cpumask function" (Jarkko).
>
> arch/x86/kernel/cpu/sgx/encl.c | 6 +++---
> arch/x86/kernel/cpu/sgx/encl.h | 2 +-
> arch/x86/kernel/cpu/sgx/main.c | 2 +-
> 3 files changed, 5 insertions(+), 5 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/sgx/encl.c b/arch/x86/kernel/cpu/sgx/encl.c
> index c6525eba74e8..8de9bebc4d81 100644
> --- a/arch/x86/kernel/cpu/sgx/encl.c
> +++ b/arch/x86/kernel/cpu/sgx/encl.c
> @@ -614,7 +614,7 @@ int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm)
> }
>
> /**
> - * sgx_encl_ewb_cpumask() - Query which CPUs might be accessing the enclave
> + * sgx_encl_cpumask() - Query which CPUs might be accessing the enclave
> * @encl: the enclave
> *
> * Some SGX functions require that no cached linear-to-physical address
> @@ -639,7 +639,7 @@ int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm)
> * The following flow is used to support SGX functions that require that
> * no cached linear-to-physical address mappings are present:
> * 1) Execute ENCLS[ETRACK] to initiate hardware tracking.
> - * 2) Use this function (sgx_encl_ewb_cpumask()) to query which CPUs might be
> + * 2) Use this function (sgx_encl_cpumask()) to query which CPUs might be
> * accessing the enclave.
> * 3) Send IPI to identified CPUs, kicking them out of the enclave and
> * thus flushing all locally cached linear-to-physical address mappings.
> @@ -656,7 +656,7 @@ int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm)
> *
> * Return: cpumask of CPUs that might be accessing @encl
> */
> -const cpumask_t *sgx_encl_ewb_cpumask(struct sgx_encl *encl)
> +const cpumask_t *sgx_encl_cpumask(struct sgx_encl *encl)
> {
> cpumask_t *cpumask = &encl->cpumask;
> struct sgx_encl_mm *encl_mm;
> diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h
> index d2acb4debde5..e59c2cbf71e2 100644
> --- a/arch/x86/kernel/cpu/sgx/encl.h
> +++ b/arch/x86/kernel/cpu/sgx/encl.h
> @@ -105,7 +105,7 @@ int sgx_encl_may_map(struct sgx_encl *encl, unsigned long start,
>
> void sgx_encl_release(struct kref *ref);
> int sgx_encl_mm_add(struct sgx_encl *encl, struct mm_struct *mm);
> -const cpumask_t *sgx_encl_ewb_cpumask(struct sgx_encl *encl);
> +const cpumask_t *sgx_encl_cpumask(struct sgx_encl *encl);
> int sgx_encl_get_backing(struct sgx_encl *encl, unsigned long page_index,
> struct sgx_backing *backing);
> void sgx_encl_put_backing(struct sgx_backing *backing, bool do_write);
> diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c
> index 2de85f459492..fa33922879bf 100644
> --- a/arch/x86/kernel/cpu/sgx/main.c
> +++ b/arch/x86/kernel/cpu/sgx/main.c
> @@ -249,7 +249,7 @@ static void sgx_encl_ewb(struct sgx_epc_page *epc_page,
> * miss cpus that entered the enclave between
> * generating the mask and incrementing epoch.
> */
> - on_each_cpu_mask(sgx_encl_ewb_cpumask(encl),
> + on_each_cpu_mask(sgx_encl_cpumask(encl),
> sgx_ipi_cb, NULL, 1);
> ret = __sgx_encl_ewb(epc_page, va_slot, backing);
> }
> --
> 2.25.1
>

Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>

BR, Jarkko