linux-kernel - [PATCH RFC 34/35] block: update comment of "struct bio_vec" regarding nth

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Message-ID: <20250821200701.1329277-35-david@redhat.com>
Date: Thu, 21 Aug 2025 22:07:00 +0200
From: David Hildenbrand <david@...hat.com>
To: linux-kernel@...r.kernel.org
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Subject: [PATCH RFC 34/35] block: update comment of "struct bio_vec" regarding nth_page()

Ever since commit 858c708d9efb ("block: move the bi_size update out of
__bio_try_merge_page"), page_is_mergeable() no longer exists, and the
logic in bvec_try_merge_page() is now a simple page pointer
comparison.

Signed-off-by: David Hildenbrand <david@...hat.com>
---
 include/linux/bvec.h | 7 ++-----
 1 file changed, 2 insertions(+), 5 deletions(-)

diff --git a/include/linux/bvec.h b/include/linux/bvec.h
index 0a80e1f9aa201..3fc0efa0825b1 100644
--- a/include/linux/bvec.h
+++ b/include/linux/bvec.h
@@ -22,11 +22,8 @@ struct page;
  * @bv_len:    Number of bytes in the address range.
  * @bv_offset: Start of the address range relative to the start of @bv_page.
  *
- * The following holds for a bvec if n * PAGE_SIZE < bv_offset + bv_len:
- *
- *   nth_page(@bv_page, n) == @bv_page + n
- *
- * This holds because page_is_mergeable() checks the above property.
+ * All pages within a bio_vec starting from @bv_page are contiguous and
+ * can simply be iterated (see bvec_advance()).
  */
 struct bio_vec {
 	struct page	*bv_page;
-- 
2.50.1