mm: update core kernel code to use vm_flags_t consistently

The core kernel code is currently very inconsistent in its use of
vm_flags_t vs.  unsigned long.  This prevents us from changing the type of
vm_flags_t in the future and is simply not correct, so correct this.

While this results in rather a lot of churn, it is a critical
pre-requisite for a future planned change to VMA flag type.

Additionally, update VMA userland tests to account for the changes.

To make review easier and to break things into smaller parts, driver and
architecture-specific changes is left for a subsequent commit.

The code has been adjusted to cascade the changes across all calling code
as far as is needed.

We will adjust architecture-specific and driver code in a subsequent patch.

Overall, this patch does not introduce any functional change.

Link: https://lkml.kernel.org/r/d1588e7bb96d1ea3fe7b9df2c699d5b4592d901d.1750274467.git.lorenzo.stoakes@oracle.com
Signed-off-by: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Acked-by: Kees Cook <kees@kernel.org>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Acked-by: Jan Kara <jack@suse.cz>
Acked-by: Christian Brauner <brauner@kernel.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Pedro Falcato <pfalcato@suse.de>
Acked-by: Zi Yan <ziy@nvidia.com>
Acked-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Jann Horn <jannh@google.com>
Cc: Liam R. Howlett <Liam.Howlett@oracle.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Jarkko Sakkinen <jarkko@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

1 files changed, 7 insertions, 7 deletions

diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 9ff970980496..95dd8dea6ee4 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -1901,11 +1901,11 @@ out:
 }
 
 static void userfaultfd_set_vm_flags(struct vm_area_struct *vma,
-				     vm_flags_t flags)
+				     vm_flags_t vm_flags)
 {
-	const bool uffd_wp_changed = (vma->vm_flags ^ flags) & VM_UFFD_WP;
+	const bool uffd_wp_changed = (vma->vm_flags ^ vm_flags) & VM_UFFD_WP;
 
-	vm_flags_reset(vma, flags);
+	vm_flags_reset(vma, vm_flags);
 	/*
 	 * For shared mappings, we want to enable writenotify while
 	 * userfaultfd-wp is enabled (see vma_wants_writenotify()). We'll simply
@@ -1917,12 +1917,12 @@ static void userfaultfd_set_vm_flags(struct vm_area_struct *vma,
 
 static void userfaultfd_set_ctx(struct vm_area_struct *vma,
 				struct userfaultfd_ctx *ctx,
-				unsigned long flags)
+				vm_flags_t vm_flags)
 {
 	vma_start_write(vma);
 	vma->vm_userfaultfd_ctx = (struct vm_userfaultfd_ctx){ctx};
 	userfaultfd_set_vm_flags(vma,
-				 (vma->vm_flags & ~__VM_UFFD_FLAGS) | flags);
+				 (vma->vm_flags & ~__VM_UFFD_FLAGS) | vm_flags);
 }
 
 void userfaultfd_reset_ctx(struct vm_area_struct *vma)
@@ -1968,14 +1968,14 @@ struct vm_area_struct *userfaultfd_clear_vma(struct vma_iterator *vmi,
 /* Assumes mmap write lock taken, and mm_struct pinned. */
 int userfaultfd_register_range(struct userfaultfd_ctx *ctx,
 			       struct vm_area_struct *vma,
-			       unsigned long vm_flags,
+			       vm_flags_t vm_flags,
 			       unsigned long start, unsigned long end,
 			       bool wp_async)
 {
 	VMA_ITERATOR(vmi, ctx->mm, start);
 	struct vm_area_struct *prev = vma_prev(&vmi);
 	unsigned long vma_end;
-	unsigned long new_flags;
+	vm_flags_t new_flags;
 
 	if (vma->vm_start < start)
 		prev = vma;