From: David Woodhouse <dwmw@amazon.co.uk>
Date: Wed, 23 Apr 2025 13:33:41 +0000 (+0100)
Subject: mm, x86: use for_each_valid_pfn() from __ioremap_check_ram()
X-Git-Tag: v6.16-rc1~92^2~88
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=49d8d78f8c6f5ef58e8dccde0d447132b7b4594a;p=thirdparty%2Flinux.git

mm, x86: use for_each_valid_pfn() from __ioremap_check_ram()

Instead of calling pfn_valid() separately for every single PFN in the
range, use for_each_valid_pfn() and only look at the ones which are.

Link: https://lkml.kernel.org/r/20250423133821.789413-6-dwmw2@infradead.org
Signed-off-by: David Woodhouse <dwmw@amazon.co.uk>
Acked-by: Mike Rapoport (Microsoft) <rppt@kernel.org>
Cc: Anshuman Khandual <anshuman.khandual@arm.com>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Marc Rutland <mark.rutland@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Ruihan Li <lrh2000@pku.edu.cn>
Cc: Will Deacon <will@kernel.org>
Cc: Lorenzo Stoakes <lorenzo.stoakes@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff --git a/arch/x86/mm/ioremap.c b/arch/x86/mm/ioremap.c
index 331e101bf801d..12c8180ca1ba7 100644
--- a/arch/x86/mm/ioremap.c
+++ b/arch/x86/mm/ioremap.c
@@ -71,7 +71,7 @@ int ioremap_change_attr(unsigned long vaddr, unsigned long size,
 static unsigned int __ioremap_check_ram(struct resource *res)
 {
 	unsigned long start_pfn, stop_pfn;
-	unsigned long i;
+	unsigned long pfn;
 
 	if ((res->flags & IORESOURCE_SYSTEM_RAM) != IORESOURCE_SYSTEM_RAM)
 		return 0;
@@ -79,9 +79,8 @@ static unsigned int __ioremap_check_ram(struct resource *res)
 	start_pfn = (res->start + PAGE_SIZE - 1) >> PAGE_SHIFT;
 	stop_pfn = (res->end + 1) >> PAGE_SHIFT;
 	if (stop_pfn > start_pfn) {
-		for (i = 0; i < (stop_pfn - start_pfn); ++i)
-			if (pfn_valid(start_pfn + i) &&
-			    !PageReserved(pfn_to_page(start_pfn + i)))
+		for_each_valid_pfn(pfn, start_pfn, stop_pfn)
+			if (!PageReserved(pfn_to_page(pfn)))
 				return IORES_MAP_SYSTEM_RAM;
 	}