linux-kernel - [PATCH] fs/sysv: Don't round down address for kunmap_flush_on

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Date:   Mon,  6 Mar 2023 13:51:50 +0100
From:   "Fabio M. De Francesco" <fmdefrancesco@...il.com>
To:     Christian Brauner <brauner@...nel.org>,
        Dave Chinner <dchinner@...hat.com>,
        Al Viro <viro@...iv.linux.org.uk>,
        "Matthew Wilcox (Oracle)" <willy@...radead.org>,
        "Fabio M. De Francesco" <fmdefrancesco@...il.com>,
        linux-kernel@...r.kernel.org
Cc:     Ira Weiny <ira.weiny@...el.com>
Subject: [PATCH] fs/sysv: Don't round down address for kunmap_flush_on_unmap()

The kernel virtual address passed to kunmap_flush_on_unmap() has no more
any need to be rounded down.

Therefore, delete the rounding down of "page_addr" when passed to
kunmap_local() in dir_put_page().

Don't backport without commit 88d7b12068b9 ("highmem: round down the
address passed to kunmap_flush_on_unmap()").

Cc: Ira Weiny <ira.weiny@...el.com>
Suggested-by: Al Viro <viro@...iv.linux.org.uk>
Signed-off-by: Fabio M. De Francesco <fmdefrancesco@...il.com>
---
 fs/sysv/dir.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/fs/sysv/dir.c b/fs/sysv/dir.c
index 999bceb99974..e2d26eb78af7 100644
--- a/fs/sysv/dir.c
+++ b/fs/sysv/dir.c
@@ -30,7 +30,7 @@ const struct file_operations sysv_dir_operations = {
 
 inline void dir_put_page(struct page *page, void *page_addr)
 {
-	kunmap_local((void *)((unsigned long)page_addr & PAGE_MASK));
+	kunmap_local(page_addr);
 	put_page(page);
 }
 
-- 
2.39.2