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From: "Kiryl Shutsemau (Meta)" <kas@kernel.org>
To: akpm@linux-foundation.org, rppt@kernel.org, peterx@redhat.com,
	david@kernel.org
Cc: ljs@kernel.org, surenb@google.com, vbabka@kernel.org,
	Liam.Howlett@oracle.com, ziy@nvidia.com, corbet@lwn.net,
	skhan@linuxfoundation.org, seanjc@google.com,
	pbonzini@redhat.com, jthoughton@google.com, aarcange@redhat.com,
	sj@kernel.org, usama.arif@linux.dev, linux-mm@kvack.org,
	linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org,
	linux-kselftest@vger.kernel.org, kvm@vger.kernel.org,
	kernel-team@meta.com, "Kiryl Shutsemau (Meta)" <kas@kernel.org>
Subject: [PATCH 02/14] mm: rename uffd-wp PTE bit macros to uffd
Date: Mon, 27 Apr 2026 12:45:50 +0100	[thread overview]
Message-ID: <20260427114607.4068647-3-kas@kernel.org> (raw)
In-Reply-To: <20260427114607.4068647-1-kas@kernel.org>

The uffd-wp PTE bit is about to gain a second consumer: userfaultfd
RWP will use the same bit to mark access-tracking PTEs, distinct
from mprotect(PROT_NONE) or NUMA-hinting PTEs. WP vs RWP semantics
come from the VMA flag; the bit is just "uffd has claimed this
entry." Drop the "_wp" suffix from the arch-private bit macros so
they reflect that.

  x86:   _PAGE_BIT_UFFD_WP  -> _PAGE_BIT_UFFD
         _PAGE_UFFD_WP      -> _PAGE_UFFD
         _PAGE_SWP_UFFD_WP  -> _PAGE_SWP_UFFD
  arm64: PTE_UFFD_WP        -> PTE_UFFD
         PTE_SWP_UFFD_WP    -> PTE_SWP_UFFD
  riscv: _PAGE_UFFD_WP      -> _PAGE_UFFD
         _PAGE_SWP_UFFD_WP  -> _PAGE_SWP_UFFD

Pure mechanical rename — no behavior change.

Signed-off-by: Kiryl Shutsemau <kas@kernel.org>
Assisted-by: Claude:claude-opus-4-6
---
 arch/arm64/include/asm/pgtable-prot.h |  8 ++++----
 arch/arm64/include/asm/pgtable.h      | 12 ++++++------
 arch/riscv/include/asm/pgtable-bits.h | 12 ++++++------
 arch/riscv/include/asm/pgtable.h      | 14 +++++++-------
 arch/x86/include/asm/pgtable.h        | 24 ++++++++++++------------
 arch/x86/include/asm/pgtable_types.h  | 16 ++++++++--------
 6 files changed, 43 insertions(+), 43 deletions(-)

diff --git a/arch/arm64/include/asm/pgtable-prot.h b/arch/arm64/include/asm/pgtable-prot.h
index 212ce1b02e15..09d7c00cf405 100644
--- a/arch/arm64/include/asm/pgtable-prot.h
+++ b/arch/arm64/include/asm/pgtable-prot.h
@@ -28,11 +28,11 @@
 #define PTE_PRESENT_VALID_KERNEL (PTE_VALID | PTE_MAYBE_NG)
 
 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
-#define PTE_UFFD_WP		(_AT(pteval_t, 1) << 58) /* uffd-wp tracking */
-#define PTE_SWP_UFFD_WP		(_AT(pteval_t, 1) << 3)	 /* only for swp ptes */
+#define PTE_UFFD		(_AT(pteval_t, 1) << 58) /* userfaultfd tracking */
+#define PTE_SWP_UFFD		(_AT(pteval_t, 1) << 3)	 /* only for swp ptes */
 #else
-#define PTE_UFFD_WP		(_AT(pteval_t, 0))
-#define PTE_SWP_UFFD_WP		(_AT(pteval_t, 0))
+#define PTE_UFFD		(_AT(pteval_t, 0))
+#define PTE_SWP_UFFD		(_AT(pteval_t, 0))
 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
 
 #define _PROT_DEFAULT		(PTE_TYPE_PAGE | PTE_AF | PTE_SHARED)
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h
index 873f4ea2e288..3eecb2c17711 100644
--- a/arch/arm64/include/asm/pgtable.h
+++ b/arch/arm64/include/asm/pgtable.h
@@ -343,17 +343,17 @@ static inline pmd_t pmd_mknoncont(pmd_t pmd)
 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
 static inline int pte_uffd_wp(pte_t pte)
 {
-	return !!(pte_val(pte) & PTE_UFFD_WP);
+	return !!(pte_val(pte) & PTE_UFFD);
 }
 
 static inline pte_t pte_mkuffd_wp(pte_t pte)
 {
-	return pte_wrprotect(set_pte_bit(pte, __pgprot(PTE_UFFD_WP)));
+	return pte_wrprotect(set_pte_bit(pte, __pgprot(PTE_UFFD)));
 }
 
 static inline pte_t pte_clear_uffd_wp(pte_t pte)
 {
-	return clear_pte_bit(pte, __pgprot(PTE_UFFD_WP));
+	return clear_pte_bit(pte, __pgprot(PTE_UFFD));
 }
 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
 
@@ -539,17 +539,17 @@ static inline pte_t pte_swp_clear_exclusive(pte_t pte)
 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
 static inline pte_t pte_swp_mkuffd_wp(pte_t pte)
 {
-	return set_pte_bit(pte, __pgprot(PTE_SWP_UFFD_WP));
+	return set_pte_bit(pte, __pgprot(PTE_SWP_UFFD));
 }
 
 static inline int pte_swp_uffd_wp(pte_t pte)
 {
-	return !!(pte_val(pte) & PTE_SWP_UFFD_WP);
+	return !!(pte_val(pte) & PTE_SWP_UFFD);
 }
 
 static inline pte_t pte_swp_clear_uffd_wp(pte_t pte)
 {
-	return clear_pte_bit(pte, __pgprot(PTE_SWP_UFFD_WP));
+	return clear_pte_bit(pte, __pgprot(PTE_SWP_UFFD));
 }
 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
 
diff --git a/arch/riscv/include/asm/pgtable-bits.h b/arch/riscv/include/asm/pgtable-bits.h
index b422d9691e60..d5a86b4df3ce 100644
--- a/arch/riscv/include/asm/pgtable-bits.h
+++ b/arch/riscv/include/asm/pgtable-bits.h
@@ -40,20 +40,20 @@
 
 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
 
-/* ext_svrsw60t59b: Bit(60) for uffd-wp tracking */
-#define _PAGE_UFFD_WP							\
+/* ext_svrsw60t59b: Bit(60) for userfaultfd tracking */
+#define _PAGE_UFFD							\
 	((riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B)) ?	\
 	 (1UL << 60) : 0)
 /*
  * Bit 4 is not involved into swap entry computation, so we
- * can borrow it for swap page uffd-wp tracking.
+ * can borrow it for swap page userfaultfd tracking.
  */
-#define _PAGE_SWP_UFFD_WP						\
+#define _PAGE_SWP_UFFD						\
 	((riscv_has_extension_unlikely(RISCV_ISA_EXT_SVRSW60T59B)) ?	\
 	 _PAGE_USER : 0)
 #else
-#define _PAGE_UFFD_WP		0
-#define _PAGE_SWP_UFFD_WP	0
+#define _PAGE_UFFD		0
+#define _PAGE_SWP_UFFD		0
 #endif
 
 #define _PAGE_TABLE     _PAGE_PRESENT
diff --git a/arch/riscv/include/asm/pgtable.h b/arch/riscv/include/asm/pgtable.h
index 48a127323b21..ca69948b3ed8 100644
--- a/arch/riscv/include/asm/pgtable.h
+++ b/arch/riscv/include/asm/pgtable.h
@@ -405,32 +405,32 @@ static inline pte_t pte_wrprotect(pte_t pte)
 
 static inline bool pte_uffd_wp(pte_t pte)
 {
-	return !!(pte_val(pte) & _PAGE_UFFD_WP);
+	return !!(pte_val(pte) & _PAGE_UFFD);
 }
 
 static inline pte_t pte_mkuffd_wp(pte_t pte)
 {
-	return pte_wrprotect(__pte(pte_val(pte) | _PAGE_UFFD_WP));
+	return pte_wrprotect(__pte(pte_val(pte) | _PAGE_UFFD));
 }
 
 static inline pte_t pte_clear_uffd_wp(pte_t pte)
 {
-	return __pte(pte_val(pte) & ~(_PAGE_UFFD_WP));
+	return __pte(pte_val(pte) & ~(_PAGE_UFFD));
 }
 
 static inline bool pte_swp_uffd_wp(pte_t pte)
 {
-	return !!(pte_val(pte) & _PAGE_SWP_UFFD_WP);
+	return !!(pte_val(pte) & _PAGE_SWP_UFFD);
 }
 
 static inline pte_t pte_swp_mkuffd_wp(pte_t pte)
 {
-	return __pte(pte_val(pte) | _PAGE_SWP_UFFD_WP);
+	return __pte(pte_val(pte) | _PAGE_SWP_UFFD);
 }
 
 static inline pte_t pte_swp_clear_uffd_wp(pte_t pte)
 {
-	return __pte(pte_val(pte) & ~(_PAGE_SWP_UFFD_WP));
+	return __pte(pte_val(pte) & ~(_PAGE_SWP_UFFD));
 }
 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
 
@@ -1157,7 +1157,7 @@ static inline pud_t pud_modify(pud_t pud, pgprot_t newprot)
  *	bit            0:	_PAGE_PRESENT (zero)
  *	bit       1 to 2:	(zero)
  *	bit            3:	_PAGE_SWP_SOFT_DIRTY
- *	bit            4:	_PAGE_SWP_UFFD_WP
+ *	bit            4:	_PAGE_SWP_UFFD
  *	bit            5:	_PAGE_PROT_NONE (zero)
  *	bit            6:	exclusive marker
  *	bits      7 to 11:	swap type
diff --git a/arch/x86/include/asm/pgtable.h b/arch/x86/include/asm/pgtable.h
index c7f014cbf0a9..038c806b50a2 100644
--- a/arch/x86/include/asm/pgtable.h
+++ b/arch/x86/include/asm/pgtable.h
@@ -413,17 +413,17 @@ static inline pte_t pte_wrprotect(pte_t pte)
 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
 static inline int pte_uffd_wp(pte_t pte)
 {
-	return pte_flags(pte) & _PAGE_UFFD_WP;
+	return pte_flags(pte) & _PAGE_UFFD;
 }
 
 static inline pte_t pte_mkuffd_wp(pte_t pte)
 {
-	return pte_wrprotect(pte_set_flags(pte, _PAGE_UFFD_WP));
+	return pte_wrprotect(pte_set_flags(pte, _PAGE_UFFD));
 }
 
 static inline pte_t pte_clear_uffd_wp(pte_t pte)
 {
-	return pte_clear_flags(pte, _PAGE_UFFD_WP);
+	return pte_clear_flags(pte, _PAGE_UFFD);
 }
 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
 
@@ -528,17 +528,17 @@ static inline pmd_t pmd_wrprotect(pmd_t pmd)
 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
 static inline int pmd_uffd_wp(pmd_t pmd)
 {
-	return pmd_flags(pmd) & _PAGE_UFFD_WP;
+	return pmd_flags(pmd) & _PAGE_UFFD;
 }
 
 static inline pmd_t pmd_mkuffd_wp(pmd_t pmd)
 {
-	return pmd_wrprotect(pmd_set_flags(pmd, _PAGE_UFFD_WP));
+	return pmd_wrprotect(pmd_set_flags(pmd, _PAGE_UFFD));
 }
 
 static inline pmd_t pmd_clear_uffd_wp(pmd_t pmd)
 {
-	return pmd_clear_flags(pmd, _PAGE_UFFD_WP);
+	return pmd_clear_flags(pmd, _PAGE_UFFD);
 }
 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
 
@@ -1550,32 +1550,32 @@ static inline pmd_t pmd_swp_clear_soft_dirty(pmd_t pmd)
 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
 static inline pte_t pte_swp_mkuffd_wp(pte_t pte)
 {
-	return pte_set_flags(pte, _PAGE_SWP_UFFD_WP);
+	return pte_set_flags(pte, _PAGE_SWP_UFFD);
 }
 
 static inline int pte_swp_uffd_wp(pte_t pte)
 {
-	return pte_flags(pte) & _PAGE_SWP_UFFD_WP;
+	return pte_flags(pte) & _PAGE_SWP_UFFD;
 }
 
 static inline pte_t pte_swp_clear_uffd_wp(pte_t pte)
 {
-	return pte_clear_flags(pte, _PAGE_SWP_UFFD_WP);
+	return pte_clear_flags(pte, _PAGE_SWP_UFFD);
 }
 
 static inline pmd_t pmd_swp_mkuffd_wp(pmd_t pmd)
 {
-	return pmd_set_flags(pmd, _PAGE_SWP_UFFD_WP);
+	return pmd_set_flags(pmd, _PAGE_SWP_UFFD);
 }
 
 static inline int pmd_swp_uffd_wp(pmd_t pmd)
 {
-	return pmd_flags(pmd) & _PAGE_SWP_UFFD_WP;
+	return pmd_flags(pmd) & _PAGE_SWP_UFFD;
 }
 
 static inline pmd_t pmd_swp_clear_uffd_wp(pmd_t pmd)
 {
-	return pmd_clear_flags(pmd, _PAGE_SWP_UFFD_WP);
+	return pmd_clear_flags(pmd, _PAGE_SWP_UFFD);
 }
 #endif /* CONFIG_HAVE_ARCH_USERFAULTFD_WP */
 
diff --git a/arch/x86/include/asm/pgtable_types.h b/arch/x86/include/asm/pgtable_types.h
index 2ec250ba467e..af08d98be930 100644
--- a/arch/x86/include/asm/pgtable_types.h
+++ b/arch/x86/include/asm/pgtable_types.h
@@ -31,7 +31,7 @@
 
 #define _PAGE_BIT_SPECIAL	_PAGE_BIT_SOFTW1
 #define _PAGE_BIT_CPA_TEST	_PAGE_BIT_SOFTW1
-#define _PAGE_BIT_UFFD_WP	_PAGE_BIT_SOFTW2 /* userfaultfd wrprotected */
+#define _PAGE_BIT_UFFD		_PAGE_BIT_SOFTW2 /* userfaultfd tracking */
 #define _PAGE_BIT_SOFT_DIRTY	_PAGE_BIT_SOFTW3 /* software dirty tracking */
 #define _PAGE_BIT_KERNEL_4K	_PAGE_BIT_SOFTW3 /* page must not be converted to large */
 
@@ -39,7 +39,7 @@
 #define _PAGE_BIT_SAVED_DIRTY	_PAGE_BIT_SOFTW5 /* Saved Dirty bit (leaf) */
 #define _PAGE_BIT_NOPTISHADOW	_PAGE_BIT_SOFTW5 /* No PTI shadow (root PGD) */
 #else
-/* Shared with _PAGE_BIT_UFFD_WP which is not supported on 32 bit */
+/* Shared with _PAGE_BIT_UFFD which is not supported on 32 bit */
 #define _PAGE_BIT_SAVED_DIRTY	_PAGE_BIT_SOFTW2 /* Saved Dirty bit (leaf) */
 #define _PAGE_BIT_NOPTISHADOW	_PAGE_BIT_SOFTW2 /* No PTI shadow (root PGD) */
 #endif
@@ -111,11 +111,11 @@
 #endif
 
 #ifdef CONFIG_HAVE_ARCH_USERFAULTFD_WP
-#define _PAGE_UFFD_WP		(_AT(pteval_t, 1) << _PAGE_BIT_UFFD_WP)
-#define _PAGE_SWP_UFFD_WP	_PAGE_USER
+#define _PAGE_UFFD		(_AT(pteval_t, 1) << _PAGE_BIT_UFFD)
+#define _PAGE_SWP_UFFD		_PAGE_USER
 #else
-#define _PAGE_UFFD_WP		(_AT(pteval_t, 0))
-#define _PAGE_SWP_UFFD_WP	(_AT(pteval_t, 0))
+#define _PAGE_UFFD		(_AT(pteval_t, 0))
+#define _PAGE_SWP_UFFD		(_AT(pteval_t, 0))
 #endif
 
 #if defined(CONFIG_X86_64) || defined(CONFIG_X86_PAE)
@@ -129,7 +129,7 @@
 /*
  * The hardware requires shadow stack to be Write=0,Dirty=1. However,
  * there are valid cases where the kernel might create read-only PTEs that
- * are dirty (e.g., fork(), mprotect(), uffd-wp(), soft-dirty tracking). In
+ * are dirty (e.g., fork(), mprotect(), userfaultfd, soft-dirty tracking). In
  * this case, the _PAGE_SAVED_DIRTY bit is used instead of the HW-dirty bit,
  * to avoid creating a wrong "shadow stack" PTEs. Such PTEs have
  * (Write=0,SavedDirty=1,Dirty=0) set.
@@ -151,7 +151,7 @@
 #define _COMMON_PAGE_CHG_MASK	(PTE_PFN_MASK | _PAGE_PCD | _PAGE_PWT |	\
 				 _PAGE_SPECIAL | _PAGE_ACCESSED |	\
 				 _PAGE_DIRTY_BITS | _PAGE_SOFT_DIRTY |	\
-				 _PAGE_CC | _PAGE_UFFD_WP)
+				 _PAGE_CC | _PAGE_UFFD)
 #define _PAGE_CHG_MASK	(_COMMON_PAGE_CHG_MASK | _PAGE_PAT)
 #define _HPAGE_CHG_MASK (_COMMON_PAGE_CHG_MASK | _PAGE_PSE | _PAGE_PAT_LARGE)
 
-- 
2.51.2


  parent reply	other threads:[~2026-04-27 11:46 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2026-04-27 11:45 [PATCH 00/14] userfaultfd: working set tracking for VM guest memory Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 01/14] mm: decouple protnone helpers from CONFIG_NUMA_BALANCING Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` Kiryl Shutsemau (Meta) [this message]
2026-04-27 11:45 ` [PATCH 03/14] mm: rename uffd-wp PTE accessors to uffd Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 04/14] mm: add VM_UFFD_RWP VMA flag Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 05/14] mm: add MM_CP_UFFD_RWP change_protection() flag Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 06/14] mm: preserve RWP marker across PTE rewrites Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 07/14] mm: handle VM_UFFD_RWP in khugepaged, rmap, and GUP Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 08/14] userfaultfd: add UFFDIO_REGISTER_MODE_RWP and UFFDIO_RWPROTECT plumbing Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 09/14] mm/userfaultfd: add RWP fault delivery and expose UFFDIO_REGISTER_MODE_RWP Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 10/14] mm/pagemap: add PAGE_IS_ACCESSED for RWP tracking Kiryl Shutsemau (Meta)
2026-04-27 11:45 ` [PATCH 11/14] userfaultfd: add UFFD_FEATURE_RWP_ASYNC for async fault resolution Kiryl Shutsemau (Meta)
2026-04-27 11:46 ` [PATCH 12/14] userfaultfd: add UFFDIO_SET_MODE for runtime sync/async toggle Kiryl Shutsemau (Meta)
2026-04-27 11:46 ` [PATCH 13/14] selftests/mm: add userfaultfd RWP tests Kiryl Shutsemau (Meta)
2026-04-27 11:46 ` [PATCH 14/14] Documentation/userfaultfd: document RWP working set tracking Kiryl Shutsemau (Meta)

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