+ x86-tdx-refactor-try_accept_one.patch added to mm-unstable branch

+ x86-tdx-refactor-try_accept_one.patch added to mm-unstable branch

[Andrew Morton]

The patch titled
     Subject: x86/tdx: refactor try_accept_one()
has been added to the -mm mm-unstable branch.  Its filename is
     x86-tdx-refactor-try_accept_one.patch

This patch will shortly appear at
     https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/x86-tdx-refactor-try_accept_one.patch

This patch will later appear in the mm-unstable branch at
    git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm

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------------------------------------------------------
From: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Subject: x86/tdx: refactor try_accept_one()
Date: Thu, 1 Jun 2023 21:25:42 +0300

Rework try_accept_one() to return accepted size instead of modifying
'start' inside the helper.  It makes 'start' in-only argument and
streamlines code on the caller side.

Link: https://lkml.kernel.org/r/20230601182543.19036-9-kirill.shutemov@linux.intel.com
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Suggested-by: Borislav Petkov <bp@alien8.de>
Reviewed-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Borislav Petkov <bp@suse.de>
Cc: Dario Faggioli <dfaggioli@suse.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Joerg Roedel <jroedel@suse.de>
Cc: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@linux.intel.com>
Cc: Liam Merwick <liam.merwick@oracle.com>
Cc: Marcelo Henrique Cerri <marcelo.cerri@canonical.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Rapoport <rppt@linux.ibm.com>
Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sean Christopherson <seanjc@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Tim Gardner <tim.gardner@canonical.com>
Cc: Tom Lendacky <thomas.lendacky@amd.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 arch/x86/coco/tdx/tdx.c |   38 +++++++++++++++++++-------------------
 1 file changed, 19 insertions(+), 19 deletions(-)

--- a/arch/x86/coco/tdx/tdx.c~x86-tdx-refactor-try_accept_one
+++ a/arch/x86/coco/tdx/tdx.c
@@ -713,18 +713,18 @@ static bool tdx_cache_flush_required(voi
 	return true;
 }
 
-static bool try_accept_one(phys_addr_t *start, unsigned long len,
-			  enum pg_level pg_level)
+static unsigned long try_accept_one(phys_addr_t start, unsigned long len,
+				    enum pg_level pg_level)
 {
 	unsigned long accept_size = page_level_size(pg_level);
 	u64 tdcall_rcx;
 	u8 page_size;
 
-	if (!IS_ALIGNED(*start, accept_size))
-		return false;
+	if (!IS_ALIGNED(start, accept_size))
+		return 0;
 
 	if (len < accept_size)
-		return false;
+		return 0;
 
 	/*
 	 * Pass the page physical address to the TDX module to accept the
@@ -743,15 +743,14 @@ static bool try_accept_one(phys_addr_t *
 		page_size = 2;
 		break;
 	default:
-		return false;
+		return 0;
 	}
 
-	tdcall_rcx = *start | page_size;
+	tdcall_rcx = start | page_size;
 	if (__tdx_module_call(TDX_ACCEPT_PAGE, tdcall_rcx, 0, 0, 0, NULL))
-		return false;
+		return 0;
 
-	*start += accept_size;
-	return true;
+	return accept_size;
 }
 
 /*
@@ -788,21 +787,22 @@ static bool tdx_enc_status_changed(unsig
 	 */
 	while (start < end) {
 		unsigned long len = end - start;
+		unsigned long accept_size;
 
 		/*
 		 * Try larger accepts first. It gives chance to VMM to keep
-		 * 1G/2M SEPT entries where possible and speeds up process by
-		 * cutting number of hypercalls (if successful).
+		 * 1G/2M Secure EPT entries where possible and speeds up
+		 * process by cutting number of hypercalls (if successful).
 		 */
 
-		if (try_accept_one(&start, len, PG_LEVEL_1G))
-			continue;
-
-		if (try_accept_one(&start, len, PG_LEVEL_2M))
-			continue;
-
-		if (!try_accept_one(&start, len, PG_LEVEL_4K))
+		accept_size = try_accept_one(start, len, PG_LEVEL_1G);
+		if (!accept_size)
+			accept_size = try_accept_one(start, len, PG_LEVEL_2M);
+		if (!accept_size)
+			accept_size = try_accept_one(start, len, PG_LEVEL_4K);
+		if (!accept_size)
 			return false;
+		start += accept_size;
 	}
 
 	return true;
_

Patches currently in -mm which might be from kirill.shutemov@linux.intel.com are

mm-add-support-for-unaccepted-memory.patch
efi-x86-get-full-memory-map-in-allocate_e820.patch
efi-libstub-implement-support-for-unaccepted-memory.patch
x86-boot-compressed-handle-unaccepted-memory.patch
efi-add-unaccepted-memory-support.patch
efi-unaccepted-avoid-load_unaligned_zeropad-stepping-into-unaccepted-memory.patch
x86-tdx-make-_tdx_hypercall-and-__tdx_module_call-available-in-boot-stub.patch
x86-tdx-refactor-try_accept_one.patch
x86-tdx-add-unaccepted-memory-support.patch