Enhance the SEAMCALL wrapper tdh_mem_page_aug() to support huge pages. The SEAMCALL TDH_MEM_PAGE_AUG currently supports adding physical memory to the S-EPT up to 2MB in size. While keeping the "level" parameter in the tdh_mem_page_aug() wrapper to allow callers to specify the physical memory size, introduce the parameters "folio" and "start_idx" to specify the physical memory starting from the page at "start_idx" within the "folio". The specified physical memory must be fully contained within a single folio. Invoke tdx_clflush_page() for each 4KB segment of the physical memory being added. tdx_clflush_page() performs CLFLUSH operations on certain TDX-capable platforms, or conservatively on all TDX-capable platforms, to prevent dirty cache lines from writing back later and corrupting TD memory. Signed-off-by: Xiaoyao Li Signed-off-by: Isaku Yamahata Signed-off-by: Yan Zhao --- RFC v2: - Refine patch log. (Rick) - Removed the level checking. (Kirill, Chao Gao) - Use "folio", and "start_idx" rather than "page". - Return TDX_OPERAND_INVALID if the specified physical memory is not contained within a single folio. - Use PTE_SHIFT to replace the 9 in "1 << (level * 9)" (Kirill) - Use C99-style definition of variables inside a loop. (Nikolay Borisov) RFC v1: - Rebased to new tdh_mem_page_aug() with "struct page *" as param. - Check folio, folio_page_idx. --- arch/x86/include/asm/tdx.h | 3 ++- arch/x86/kvm/vmx/tdx.c | 4 +++- arch/x86/virt/vmx/tdx/tdx.c | 14 +++++++++++--- 3 files changed, 16 insertions(+), 5 deletions(-) diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h index 48d579092590..f968b736871a 100644 --- a/arch/x86/include/asm/tdx.h +++ b/arch/x86/include/asm/tdx.h @@ -171,7 +171,8 @@ u64 tdh_mng_addcx(struct tdx_td *td, struct page *tdcs_page); u64 tdh_mem_page_add(struct tdx_td *td, u64 gpa, struct page *page, struct page *source, u64 *ext_err1, u64 *ext_err2); u64 tdh_mem_sept_add(struct tdx_td *td, u64 gpa, int level, struct page *page, u64 *ext_err1, u64 *ext_err2); u64 tdh_vp_addcx(struct tdx_vp *vp, struct page *tdcx_page); -u64 tdh_mem_page_aug(struct tdx_td *td, u64 gpa, int level, struct page *page, u64 *ext_err1, u64 *ext_err2); +u64 tdh_mem_page_aug(struct tdx_td *td, u64 gpa, int level, struct folio *folio, + unsigned long start_idx, u64 *ext_err1, u64 *ext_err2); u64 tdh_mem_range_block(struct tdx_td *td, u64 gpa, int level, u64 *ext_err1, u64 *ext_err2); u64 tdh_mng_key_config(struct tdx_td *td); u64 tdh_mng_create(struct tdx_td *td, u16 hkid); diff --git a/arch/x86/kvm/vmx/tdx.c b/arch/x86/kvm/vmx/tdx.c index ed67f842b6ec..0a2b183899d8 100644 --- a/arch/x86/kvm/vmx/tdx.c +++ b/arch/x86/kvm/vmx/tdx.c @@ -1593,11 +1593,13 @@ static int tdx_mem_page_aug(struct kvm *kvm, gfn_t gfn, { int tdx_level = pg_level_to_tdx_sept_level(level); struct kvm_tdx *kvm_tdx = to_kvm_tdx(kvm); + struct folio *folio = page_folio(page); gpa_t gpa = gfn_to_gpa(gfn); u64 entry, level_state; u64 err; - err = tdh_mem_page_aug(&kvm_tdx->td, gpa, tdx_level, page, &entry, &level_state); + err = tdh_mem_page_aug(&kvm_tdx->td, gpa, tdx_level, folio, + folio_page_idx(folio, page), &entry, &level_state); if (unlikely(tdx_operand_busy(err))) { tdx_unpin(kvm, page); return -EBUSY; diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c index e411cf878547..580f14f64822 100644 --- a/arch/x86/virt/vmx/tdx/tdx.c +++ b/arch/x86/virt/vmx/tdx/tdx.c @@ -1730,16 +1730,24 @@ u64 tdh_vp_addcx(struct tdx_vp *vp, struct page *tdcx_page) } EXPORT_SYMBOL_GPL(tdh_vp_addcx); -u64 tdh_mem_page_aug(struct tdx_td *td, u64 gpa, int level, struct page *page, u64 *ext_err1, u64 *ext_err2) +u64 tdh_mem_page_aug(struct tdx_td *td, u64 gpa, int level, struct folio *folio, + unsigned long start_idx, u64 *ext_err1, u64 *ext_err2) { + struct page *start = folio_page(folio, start_idx); + unsigned long npages = 1 << (level * PTE_SHIFT); struct tdx_module_args args = { .rcx = gpa | level, .rdx = tdx_tdr_pa(td), - .r8 = page_to_phys(page), + .r8 = page_to_phys(start), }; u64 ret; - tdx_clflush_page(page); + if (start_idx + npages > folio_nr_pages(folio)) + return TDX_OPERAND_INVALID; + + for (int i = 0; i < npages; i++) + tdx_clflush_page(nth_page(start, i)); + ret = seamcall_ret(TDH_MEM_PAGE_AUG, &args); *ext_err1 = args.rcx; -- 2.43.2