x86/tdx: Rename __tdx_module_call() to __tdcall()

__tdx_module_call() is only used by the TDX guest to issue TDCALL to the
TDX module.  Rename it to __tdcall() to match its behaviour, e.g., it
cannot be used to make host-side SEAMCALL.

Also rename tdx_module_call() which is a wrapper of __tdx_module_call()
to tdcall().

No functional change intended.

Signed-off-by: Kai Huang <kai.huang@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/all/785d20d99fbcd0db8262c94da6423375422d8c75.1692096753.git.kai.huang%40intel.com

Author: kaihuang

arch/x86/coco/tdx/tdcall.S

@@ -40,8 +40,8 @@
 .section .noinstr.text, "ax"
 
 /*
- * __tdx_module_call()  - Used by TDX guests to request services from
- * the TDX module (does not include VMM services) using TDCALL instruction.
+ * __tdcall()  - Used by TDX guests to request services from the TDX
+ * module (does not include VMM services) using TDCALL instruction.
  *
  * Transforms function call register arguments into the TDCALL register ABI.
  * After TDCALL operation, TDX module output is saved in @out (if it is
@@ -62,7 +62,7 @@
  *
  *-------------------------------------------------------------------------
  *
- * __tdx_module_call() function ABI:
+ * __tdcall() function ABI:
  *
  * @fn  (RDI)          - TDCALL Leaf ID,    moved to RAX
  * @rcx (RSI)          - Input parameter 1, moved to RCX
@@ -77,9 +77,9 @@
  *
  * Return status of TDCALL via RAX.
  */
-SYM_FUNC_START(__tdx_module_call)
+SYM_FUNC_START(__tdcall)
 	TDX_MODULE_CALL host=0
-SYM_FUNC_END(__tdx_module_call)
+SYM_FUNC_END(__tdcall)
 
 /*
  * TDX_HYPERCALL - Make hypercalls to a TDX VMM using TDVMCALL leaf of TDCALL

arch/x86/coco/tdx/tdx-shared.c

@@ -35,7 +35,7 @@ static unsigned long try_accept_one(phys_addr_t start, unsigned long len,
 	}
 
 	tdcall_rcx = start | page_size;
-	if (__tdx_module_call(TDG_MEM_PAGE_ACCEPT, tdcall_rcx, 0, 0, 0, NULL))
+	if (__tdcall(TDG_MEM_PAGE_ACCEPT, tdcall_rcx, 0, 0, 0, NULL))
 		return 0;
 
 	return accept_size;

arch/x86/coco/tdx/tdx.c

@@ -66,10 +66,10 @@ EXPORT_SYMBOL_GPL(tdx_kvm_hypercall);
  * should only be used for calls that have no legitimate reason to fail
  * or where the kernel can not survive the call failing.
  */
-static inline void tdx_module_call(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9,
-				   struct tdx_module_output *out)
+static inline void tdcall(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9,
+			  struct tdx_module_output *out)
 {
-	if (__tdx_module_call(fn, rcx, rdx, r8, r9, out))
+	if (__tdcall(fn, rcx, rdx, r8, r9, out))
 		panic("TDCALL %lld failed (Buggy TDX module!)\n", fn);
 }
 
@@ -91,9 +91,9 @@ int tdx_mcall_get_report0(u8 *reportdata, u8 *tdreport)
 {
 	u64 ret;
 
-	ret = __tdx_module_call(TDG_MR_REPORT, virt_to_phys(tdreport),
-				virt_to_phys(reportdata), TDREPORT_SUBTYPE_0,
-				0, NULL);
+	ret = __tdcall(TDG_MR_REPORT, virt_to_phys(tdreport),
+			virt_to_phys(reportdata), TDREPORT_SUBTYPE_0,
+			0, NULL);
 	if (ret) {
 		if (TDCALL_RETURN_CODE(ret) == TDCALL_INVALID_OPERAND)
 			return -EINVAL;
@@ -152,7 +152,7 @@ static void tdx_parse_tdinfo(u64 *cc_mask)
 	 * Guest-Host-Communication Interface (GHCI), section 2.4.2 TDCALL
 	 * [TDG.VP.INFO].
 	 */
-	tdx_module_call(TDG_VP_INFO, 0, 0, 0, 0, &out);
+	tdcall(TDG_VP_INFO, 0, 0, 0, 0, &out);
 
 	/*
 	 * The highest bit of a guest physical address is the "sharing" bit.
@@ -594,7 +594,7 @@ void tdx_get_ve_info(struct ve_info *ve)
 	 * Note, the TDX module treats virtual NMIs as inhibited if the #VE
 	 * valid flag is set. It means that NMI=>#VE will not result in a #DF.
 	 */
-	tdx_module_call(TDG_VP_VEINFO_GET, 0, 0, 0, 0, &out);
+	tdcall(TDG_VP_VEINFO_GET, 0, 0, 0, 0, &out);
 
 	/* Transfer the output parameters */
 	ve->exit_reason = out.rcx;
@@ -814,7 +814,7 @@ void __init tdx_early_init(void)
 	cc_set_mask(cc_mask);
 
 	/* Kernel does not use NOTIFY_ENABLES and does not need random #VEs */
-	tdx_module_call(TDG_VM_WR, 0, TDCS_NOTIFY_ENABLES, 0, -1ULL, NULL);
+	tdcall(TDG_VM_WR, 0, TDCS_NOTIFY_ENABLES, 0, -1ULL, NULL);
 
 	/*
 	 * All bits above GPA width are reserved and kernel treats shared bit

arch/x86/include/asm/shared/tdx.h

@@ -90,8 +90,8 @@ struct tdx_module_output {
 };
 
 /* Used to communicate with the TDX module */
-u64 __tdx_module_call(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9,
-		      struct tdx_module_output *out);
+u64 __tdcall(u64 fn, u64 rcx, u64 rdx, u64 r8, u64 r9,
+	     struct tdx_module_output *out);
 
 bool tdx_accept_memory(phys_addr_t start, phys_addr_t end);