Re: [PATCH 10/13] x86/virt/tdx: Add SEAMCALL wrappers to remove a TD private page

Yan Zhao
2025-01-07T06:44:13Z

New diffs and changelog:
SEAMCALL RFC:
- For tdh_mem_page_remove()
a) Use struct tdx_td instead of raw TDR u64
b) Change "u64 level" to "int tdx_level".
c) Change "u64 gpa" to "gfn_t gfn". (Reinette)
d) Use union tdx_sept_gpa_mapping_info to initialize args.rcx. (Reinette)
e) Use extended_err1/2 instead of rcx/rdx for output.
- For tdh_phymem_page_wbinvd_hkid()
a) Use "struct page *" instead of raw hpa.
b) Change "u64 hkid" to "u16 hkid" (Reinette)

diff --git a/arch/x86/include/asm/tdx.h b/arch/x86/include/asm/tdx.h
index 980daa142e92..be0fc55186a8 100644
--- a/arch/x86/include/asm/tdx.h
+++ b/arch/x86/include/asm/tdx.h
@@ -168,8 +168,11 @@ u64 tdh_vp_wr(struct tdx_vp *vp, u64 field, u64 data, u64 mask);
u64 tdh_vp_init_apicid(struct tdx_vp *vp, u64 initial_rcx, u32 x2apicid);
u64 tdh_phymem_page_reclaim(struct page *page, u64 *tdx_pt, u64 *tdx_owner, u64 *tdx_size);
u64 tdh_mem_track(struct tdx_td *td);
+u64 tdh_mem_page_remove(struct tdx_td *td, gfn_t gfn, int tdx_level,
+ u64 *extended_err1, u64 *extended_err2);
u64 tdh_phymem_cache_wb(bool resume);
u64 tdh_phymem_page_wbinvd_tdr(struct tdx_td *td);
+u64 tdh_phymem_page_wbinvd_hkid(struct page *page, u16 hkid);
#else
static inline void tdx_init(void) { }
static inline int tdx_cpu_enable(void) { return -ENODEV; }
diff --git a/arch/x86/virt/vmx/tdx/tdx.c b/arch/x86/virt/vmx/tdx/tdx.c
index 120a415c1d7a..b4e4cfce3475 100644
--- a/arch/x86/virt/vmx/tdx/tdx.c
+++ b/arch/x86/virt/vmx/tdx/tdx.c
@@ -1862,6 +1862,25 @@ u64 tdh_mem_track(struct tdx_td *td)
}
EXPORT_SYMBOL_GPL(tdh_mem_track);

+u64 tdh_mem_page_remove(struct tdx_td *td, gfn_t gfn, int tdx_level,
+ u64 *extended_err1, u64 *extended_err2)
+{
+ union tdx_sept_gpa_mapping_info gpa_info = { .level = tdx_level, .gfn = gfn, };
+ struct tdx_module_args args = {
+ .rcx = gpa_info.full,
+ .rdx = tdx_tdr_pa(td),
+ };
+ u64 ret;
+
+ ret = seamcall_ret(TDH_MEM_PAGE_REMOVE, &args);
+
+ *extended_err1 = args.rcx;
+ *extended_err2 = args.rdx;
+
+ return ret;
+}
+EXPORT_SYMBOL_GPL(tdh_mem_page_remove);
+
u64 tdh_phymem_cache_wb(bool resume)
{
struct tdx_module_args args = {
@@ -1882,3 +1901,12 @@ u64 tdh_phymem_page_wbinvd_tdr(struct tdx_td *td)
}
EXPORT_SYMBOL_GPL(tdh_phymem_page_wbinvd_tdr);

+u64 tdh_phymem_page_wbinvd_hkid(struct page *page, u16 hkid)
+{
+ struct tdx_module_args args = {};
+
+ args.rcx = page_to_phys(page) | ((hpa_t)hkid << boot_cpu_data.x86_phys_bits);
+
+ return seamcall(TDH_PHYMEM_PAGE_WBINVD, &args);
+}
+EXPORT_SYMBOL_GPL(tdh_phymem_page_wbinvd_hkid);
diff --git a/arch/x86/virt/vmx/tdx/tdx.h b/arch/x86/virt/vmx/tdx/tdx.h
index 24e32c838926..4de17d9c2e8c 100644
--- a/arch/x86/virt/vmx/tdx/tdx.h
+++ b/arch/x86/virt/vmx/tdx/tdx.h
@@ -35,6 +35,7 @@
#define TDH_PHYMEM_PAGE_RDMD 24
#define TDH_VP_RD 26
#define TDH_PHYMEM_PAGE_RECLAIM 28
+#define TDH_MEM_PAGE_REMOVE 29
#define TDH_SYS_KEY_CONFIG 31
#define TDH_SYS_INIT 33
#define TDH_SYS_RD 34