Re: [PATCH 4/7] maccess: Use a scoped guard for page faults

Kernel nofault copy and string paths open-code page-fault disable and
enable around label-based loops, duplicating cleanup on success and
failure.

Use a page-fault scope guard instead. Leaving the scope now re-enables
page faults on both paths without separate cleanup at the fault label.

No functional change.

Signed-off-by: Muhammad Usama Anjum <redacted>
---
 mm/maccess.c | 53 +++++++++++++++++++++++++---------------------------
 1 file changed, 25 insertions(+), 28 deletions(-)

diff --git a/mm/maccess.c b/mm/maccess.c
index c59a0e092d24a..f695ceefe6fcc 100644
--- a/mm/maccess.c
+++ b/mm/maccess.c

@@ -38,18 +38,17 @@ long copy_from_kernel_nofault(void *dst, const void *src, size_t size)
 	if (!size)
 		return 0;
 
-	pagefault_disable();
-	if (!(align & 7))
-		copy_from_kernel_nofault_loop(dst, src, size, u64, Efault);
-	if (!(align & 3))
-		copy_from_kernel_nofault_loop(dst, src, size, u32, Efault);
-	if (!(align & 1))
-		copy_from_kernel_nofault_loop(dst, src, size, u16, Efault);
-	copy_from_kernel_nofault_loop(dst, src, size, u8, Efault);
-	pagefault_enable();
+	scoped_guard(pagefault) {
+		if (!(align & 7))
+			copy_from_kernel_nofault_loop(dst, src, size, u64, Efault);
+		if (!(align & 3))
+			copy_from_kernel_nofault_loop(dst, src, size, u32, Efault);
+		if (!(align & 1))
+			copy_from_kernel_nofault_loop(dst, src, size, u16, Efault);
+		copy_from_kernel_nofault_loop(dst, src, size, u8, Efault);
+	}