[PATCH v2 2/6] mm: replace VM_LOCKED_CLEAR_MASK with VM_LOCKED_MASK

Suren Baghdasaryan surenb at google.com
Wed Jan 25 00:38:47 PST 2023


To simplify the usage of VM_LOCKED_CLEAR_MASK in clear_vm_flags(),
replace it with VM_LOCKED_MASK bitmask and convert all users.

Signed-off-by: Suren Baghdasaryan <surenb at google.com>
---
 include/linux/mm.h | 4 ++--
 kernel/fork.c      | 2 +-
 mm/hugetlb.c       | 4 ++--
 mm/mlock.c         | 6 +++---
 mm/mmap.c          | 6 +++---
 mm/mremap.c        | 2 +-
 6 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/include/linux/mm.h b/include/linux/mm.h
index b71f2809caac..da62bdd627bf 100644
--- a/include/linux/mm.h
+++ b/include/linux/mm.h
@@ -421,8 +421,8 @@ extern unsigned int kobjsize(const void *objp);
 /* This mask defines which mm->def_flags a process can inherit its parent */
 #define VM_INIT_DEF_MASK	VM_NOHUGEPAGE
 
-/* This mask is used to clear all the VMA flags used by mlock */
-#define VM_LOCKED_CLEAR_MASK	(~(VM_LOCKED | VM_LOCKONFAULT))
+/* This mask represents all the VMA flag bits used by mlock */
+#define VM_LOCKED_MASK	(VM_LOCKED | VM_LOCKONFAULT)
 
 /* Arch-specific flags to clear when updating VM flags on protection change */
 #ifndef VM_ARCH_CLEAR
diff --git a/kernel/fork.c b/kernel/fork.c
index 6683c1b0f460..03d472051236 100644
--- a/kernel/fork.c
+++ b/kernel/fork.c
@@ -669,7 +669,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm,
 			tmp->anon_vma = NULL;
 		} else if (anon_vma_fork(tmp, mpnt))
 			goto fail_nomem_anon_vma_fork;
-		tmp->vm_flags &= ~(VM_LOCKED | VM_LOCKONFAULT);
+		clear_vm_flags(tmp, VM_LOCKED_MASK);
 		file = tmp->vm_file;
 		if (file) {
 			struct address_space *mapping = file->f_mapping;
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index d20c8b09890e..4ecdbad9a451 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -6973,8 +6973,8 @@ static unsigned long page_table_shareable(struct vm_area_struct *svma,
 	unsigned long s_end = sbase + PUD_SIZE;
 
 	/* Allow segments to share if only one is marked locked */
-	unsigned long vm_flags = vma->vm_flags & VM_LOCKED_CLEAR_MASK;
-	unsigned long svm_flags = svma->vm_flags & VM_LOCKED_CLEAR_MASK;
+	unsigned long vm_flags = vma->vm_flags & ~VM_LOCKED_MASK;
+	unsigned long svm_flags = svma->vm_flags & ~VM_LOCKED_MASK;
 
 	/*
 	 * match the virtual addresses, permission and the alignment of the
diff --git a/mm/mlock.c b/mm/mlock.c
index 0336f52e03d7..5c4fff93cd6b 100644
--- a/mm/mlock.c
+++ b/mm/mlock.c
@@ -497,7 +497,7 @@ static int apply_vma_lock_flags(unsigned long start, size_t len,
 		if (vma->vm_start != tmp)
 			return -ENOMEM;
 
-		newflags = vma->vm_flags & VM_LOCKED_CLEAR_MASK;
+		newflags = vma->vm_flags & ~VM_LOCKED_MASK;
 		newflags |= flags;
 		/* Here we know that  vma->vm_start <= nstart < vma->vm_end. */
 		tmp = vma->vm_end;
@@ -661,7 +661,7 @@ static int apply_mlockall_flags(int flags)
 	struct vm_area_struct *vma, *prev = NULL;
 	vm_flags_t to_add = 0;
 
-	current->mm->def_flags &= VM_LOCKED_CLEAR_MASK;
+	current->mm->def_flags &= ~VM_LOCKED_MASK;
 	if (flags & MCL_FUTURE) {
 		current->mm->def_flags |= VM_LOCKED;
 
@@ -681,7 +681,7 @@ static int apply_mlockall_flags(int flags)
 	for_each_vma(vmi, vma) {
 		vm_flags_t newflags;
 
-		newflags = vma->vm_flags & VM_LOCKED_CLEAR_MASK;
+		newflags = vma->vm_flags & ~VM_LOCKED_MASK;
 		newflags |= to_add;
 
 		/* Ignore errors */
diff --git a/mm/mmap.c b/mm/mmap.c
index d4abc6feced1..323bd253b25a 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -2671,7 +2671,7 @@ unsigned long mmap_region(struct file *file, unsigned long addr,
 		if ((vm_flags & VM_SPECIAL) || vma_is_dax(vma) ||
 					is_vm_hugetlb_page(vma) ||
 					vma == get_gate_vma(current->mm))
-			vma->vm_flags &= VM_LOCKED_CLEAR_MASK;
+			clear_vm_flags(vma, VM_LOCKED_MASK);
 		else
 			mm->locked_vm += (len >> PAGE_SHIFT);
 	}
@@ -3340,8 +3340,8 @@ static struct vm_area_struct *__install_special_mapping(
 	vma->vm_start = addr;
 	vma->vm_end = addr + len;
 
-	vma->vm_flags = vm_flags | mm->def_flags | VM_DONTEXPAND | VM_SOFTDIRTY;
-	vma->vm_flags &= VM_LOCKED_CLEAR_MASK;
+	init_vm_flags(vma, (vm_flags | mm->def_flags |
+		      VM_DONTEXPAND | VM_SOFTDIRTY) & ~VM_LOCKED_MASK);
 	vma->vm_page_prot = vm_get_page_prot(vma->vm_flags);
 
 	vma->vm_ops = ops;
diff --git a/mm/mremap.c b/mm/mremap.c
index 1b3ee02bead7..35db9752cb6a 100644
--- a/mm/mremap.c
+++ b/mm/mremap.c
@@ -687,7 +687,7 @@ static unsigned long move_vma(struct vm_area_struct *vma,
 
 	if (unlikely(!err && (flags & MREMAP_DONTUNMAP))) {
 		/* We always clear VM_LOCKED[ONFAULT] on the old vma */
-		vma->vm_flags &= VM_LOCKED_CLEAR_MASK;
+		clear_vm_flags(vma, VM_LOCKED_MASK);
 
 		/*
 		 * anon_vma links of the old vma is no longer needed after its page
-- 
2.39.1




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