linux-kernel - [PATCH RFC 15/35] fs: hugetlbfs: remove nth_page() usage within folio in adjust_range

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Message-ID: <20250821200701.1329277-16-david@redhat.com>
Date: Thu, 21 Aug 2025 22:06:41 +0200
From: David Hildenbrand <david@...hat.com>
To: linux-kernel@...r.kernel.org
Cc: David Hildenbrand <david@...hat.com>,
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Subject: [PATCH RFC 15/35] fs: hugetlbfs: remove nth_page() usage within folio in adjust_range_hwpoison()

The nth_page() is not really required anymore, so let's remove it.
While at it, cleanup and simplify the code a bit.

Signed-off-by: David Hildenbrand <david@...hat.com>
---
 fs/hugetlbfs/inode.c | 25 ++++++++-----------------
 1 file changed, 8 insertions(+), 17 deletions(-)

diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c
index 34d496a2b7de6..dc981509a7717 100644
--- a/fs/hugetlbfs/inode.c
+++ b/fs/hugetlbfs/inode.c
@@ -198,31 +198,22 @@ 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;
+	struct page *page = folio_page(folio, offset / PAGE_SIZE);
+	size_t n, safe_bytes;
 
-	/* First page to start the loop. */
-	page = folio_page(folio, offset / PAGE_SIZE);
 	offset %= PAGE_SIZE;
-	while (1) {
+	for (safe_bytes = 0; safe_bytes < bytes; safe_bytes += n) {
+
 		if (is_raw_hwpoison_page_in_hugepage(page))
 			break;
 
 		/* Safe to read n bytes without touching HWPOISON subpage. */
-		n = min(bytes, (size_t)PAGE_SIZE - offset);
-		res += n;
-		bytes -= n;
-		if (!bytes || !n)
-			break;
-		offset += n;
-		if (offset == PAGE_SIZE) {
-			page = nth_page(page, 1);
-			offset = 0;
-		}
+		n = min(bytes - safe_bytes, (size_t)PAGE_SIZE - offset);
+		offset = 0;
+		page++;
 	}
 
-	return res;
+	return safe_bytes;
 }
 
 /*
-- 
2.50.1