linux-kernel - [PATCH v1 16/36] fs: hugetlbfs: cleanup folio in adjust_range

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Message-ID: <20250827220141.262669-17-david@redhat.com>
Date: Thu, 28 Aug 2025 00:01:20 +0200
From: David Hildenbrand <david@...hat.com>
To: linux-kernel@...r.kernel.org
Cc: David Hildenbrand <david@...hat.com>,
	Alexander Potapenko <glider@...gle.com>,
	Andrew Morton <akpm@...ux-foundation.org>,
	Brendan Jackman <jackmanb@...gle.com>,
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	Zi Yan <ziy@...dia.com>
Subject: [PATCH v1 16/36] fs: hugetlbfs: cleanup folio in adjust_range_hwpoison()

Let's cleanup and simplify the function a bit.

Signed-off-by: David Hildenbrand <david@...hat.com>
---
 fs/hugetlbfs/inode.c | 33 +++++++++++----------------------
 1 file changed, 11 insertions(+), 22 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index c5a46d10afaa0..6ca1f6b45c1e5 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -198,31 +198,20 @@ hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
 static size_t adjust_range_hwpoison(struct folio *folio, size_t offset,
 		size_t bytes)
 {
-	struct page *page;
-	size_t n = 0;
-	size_t res = 0;
-
-	/* First page to start the loop. */
-	page = folio_page(folio, offset / PAGE_SIZE);
-	offset %= PAGE_SIZE;
-	while (1) {
-		if (is_raw_hwpoison_page_in_hugepage(page))
-			break;
+	struct page *page = folio_page(folio, offset / PAGE_SIZE);
+	size_t safe_bytes;
+
+	if (is_raw_hwpoison_page_in_hugepage(page))
+		return 0;
+	/* Safe to read the remaining bytes in this page. */
+	safe_bytes = PAGE_SIZE - (offset % PAGE_SIZE);
+	page++;
 
-		/* Safe to read n bytes without touching HWPOISON subpage. */
-		n = min(bytes, (size_t)PAGE_SIZE - offset);
-		res += n;
-		bytes -= n;
-		if (!bytes || !n)
+	for (; safe_bytes < bytes; safe_bytes += PAGE_SIZE, page++)
+		if (is_raw_hwpoison_page_in_hugepage(page))
 			break;
-		offset += n;
-		if (offset == PAGE_SIZE) {
-			page++;
-			offset = 0;
-		}
-	}
 
-	return res;
+	return min(safe_bytes, bytes);
 }
 
 /*
-- 
2.50.1