lists.openwall.net   lists  /  announce  owl-users  owl-dev  john-users  john-dev  passwdqc-users  yescrypt  popa3d-users  /  oss-security  kernel-hardening  musl  sabotage  tlsify  passwords  /  crypt-dev  xvendor  /  Bugtraq  Full-Disclosure  linux-kernel  linux-netdev  linux-ext4  linux-hardening  linux-cve-announce  PHC 
Open Source and information security mailing list archives
 
Hash Suite: Windows password security audit tool. GUI, reports in PDF.
[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]
Date:   Tue, 24 Oct 2023 11:52:15 +0800
From:   Gou Hao <gouhao@...ontech.com>
To:     gouhao@...ontech.com
Cc:     adilger.kernel@...ger.ca, gouhaojake@....com, jack@...e.cz,
        linux-ext4@...r.kernel.org, linux-kernel@...r.kernel.org,
        tytso@....edu
Subject: [PATCH V2] ext4: delete redundant calculations in ext4_mb_get_buddy_page_lock()

'blocks_per_page' is always 1 after 'if (blocks_per_page >= 2)',
'pnum' and 'block' are equal in this case.

Signed-off-by: Gou Hao <gouhao@...ontech.com>
Reviewed-by: Jan Kara <jack@...e.cz>
---
 fs/ext4/mballoc.c | 5 ++---
 1 file changed, 2 insertions(+), 3 deletions(-)

diff --git a/fs/ext4/mballoc.c b/fs/ext4/mballoc.c
index 454d5612641e..c340d4d7287a 100644
--- a/fs/ext4/mballoc.c
+++ b/fs/ext4/mballoc.c
@@ -1456,9 +1456,8 @@ static int ext4_mb_get_buddy_page_lock(struct super_block *sb,
 		return 0;
 	}
 
-	block++;
-	pnum = block / blocks_per_page;
-	page = find_or_create_page(inode->i_mapping, pnum, gfp);
+	/* blocks_per_page == 1, hence we need another page for the buddy */
+	page = find_or_create_page(inode->i_mapping, block + 1, gfp);
 	if (!page)
 		return -ENOMEM;
 	BUG_ON(page->mapping != inode->i_mapping);
-- 
2.20.1

Powered by blists - more mailing lists