[PATCH v2 12/13] mm/mprotect: convert mprotect code to use vma_flags_t

Lorenzo Stoakes <[email protected]> Sat, 11 Jul 2026 19:45:09 +0100
Newsgroups gmane.comp.freedesktop.xorg.drivers.freedreno,gmane.linux.kernel.mm,gmane.linux.kernel,gmane.linux.ports.mips,gmane.linux.kernel.aio.general,gmane.linux.file-systems,gmane.linux.ports.ppc64.devel,gmane.comp.video.dri.devel,gmane.linux.ports.arm.kernel,gmane.linux.kernel.samsung-soc,gmane.comp.freedesktop.xorg.drivers.intel,gmane.linux.ports.arm.msm,gmane.comp.freedesktop.xorg.nouveau,gmane.linux.ports.arm.rockchip,gmane.linux.ports.tegra,gmane.comp.emulators.xen.devel,gmane.linux.sound
Message-ID <[email protected]> 
Replace use of the legacy vm_flags_t flags with vma_flags_t values
throughout the mprotect logic.

Note that we retain the legacy vm_flags_t bit shifting code in
do_mprotect_pkey(), deferring a vma_flags_t approach to this for the time
being.

Additionally update comments to reflect the changes to be consistent.

No functional change intended.

Signed-off-by: Lorenzo Stoakes <[email protected]>
---
 mm/mprotect.c | 16 ++++++++--------
 1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/mm/mprotect.c b/mm/mprotect.c
index dc27bbc1712f..2888ee638d87 100644
--- a/mm/mprotect.c
+++ b/mm/mprotect.c
@@ -40,7 +40,7 @@
 
 static bool maybe_change_pte_writable(struct vm_area_struct *vma, pte_t pte)
 {
-	if (WARN_ON_ONCE(!(vma->vm_flags & VM_WRITE)))
+	if (WARN_ON_ONCE(!vma_test(vma, VMA_WRITE_BIT)))
 		return false;
 
 	/* Don't touch entries that are not even readable. */
@@ -97,7 +97,7 @@ static bool can_change_shared_pte_writable(struct vm_area_struct *vma,
 bool can_change_pte_writable(struct vm_area_struct *vma, unsigned long addr,
 			     pte_t pte)
 {
-	if (!(vma->vm_flags & VM_SHARED))
+	if (!vma_test(vma, VMA_SHARED_BIT))
 		return can_change_private_pte_writable(vma, addr, pte);
 
 	return can_change_shared_pte_writable(vma, pte);
@@ -194,7 +194,7 @@ static __always_inline void set_write_prot_commit_flush_ptes(struct vm_area_stru
 {
 	bool set_write;
 
-	if (vma->vm_flags & VM_SHARED) {
+	if (vma_test(vma, VMA_SHARED_BIT)) {
 		set_write = can_change_shared_pte_writable(vma, ptent);
 		prot_commit_flush_ptes(vma, addr, ptep, oldpte, ptent, nr_ptes,
 				       /* idx = */ 0, set_write, tlb);
@@ -846,8 +846,8 @@ mprotect_fixup(struct vma_iterator *vmi, struct mmu_gather *tlb,
 		vm_unacct_memory(nrpages);
 
 	/*
-	 * Private VM_LOCKED VMA becoming writable: trigger COW to avoid major
-	 * fault on access.
+	 * Private VMA_LOCKED_BIT VMA becoming writable: trigger COW to avoid
+	 * major fault on access.
 	 */
 	if (vma_flags_test(&new_vma_flags, VMA_WRITE_BIT) &&
 	    vma_flags_test(&old_vma_flags, VMA_LOCKED_BIT) &&
@@ -921,7 +921,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
 			goto out;
 		start = vma->vm_start;
 		error = -EINVAL;
-		if (!(vma->vm_flags & VM_GROWSDOWN))
+		if (!vma_test(vma, VMA_GROWSDOWN_BIT))
 			goto out;
 	} else {
 		if (vma->vm_start > start)
@@ -929,7 +929,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
 		if (unlikely(grows & PROT_GROWSUP)) {
 			end = vma->vm_end;
 			error = -EINVAL;
-			if (!(vma->vm_flags & VM_GROWSUP))
+			if (!vma_test_single_mask(vma, VMA_GROWSUP))
 				goto out;
 		}
 	}
@@ -953,7 +953,7 @@ static int do_mprotect_pkey(unsigned long start, size_t len,
 		}
 
 		/* Does the application expect PROT_READ to imply PROT_EXEC */
-		if (rier && (vma->vm_flags & VM_MAYEXEC))
+		if (rier && vma_test(vma, VMA_MAYEXEC_BIT))
 			prot |= PROT_EXEC;
 
 		/*

-- 
2.55.0