From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 636484534B0; Tue, 31 Mar 2026 21:28:47 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774992527; cv=none; b=cLxOINGqx1i/BVr9seM/zhN0ZWPFxkI/fpLkU/JT/j709g4JDR0N/6Ni55EONeVKSQLOGLY0MnRc5mPECJ297Rb93bwjoM6GJ2Y0+jtkD1VwkkUfcvE06UEEg37uuHZXmt2/RJMv8ovzPB4H/Nm/nEBMcwr9WdlempseYcw0gYk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774992527; c=relaxed/simple; bh=WJ1MvN8V+hC/HPZfDG3Jxx2eF+NqyWJKvekF+n3PMXc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=XTbzNMYKyc/xMWTZ/rfxlC1T7B/rDFJBcqqQq+yuI4Cw3M3kgoGr+SXm7RQ2cfz6O8ljcHh7RBSMmoOgBtJT1q9y8sdVcHVtsmXHcPfTPYV/9GYyBwfWfbYOQw/ZwXmwHASkTCdBL5EkT8IsiT8f7qsbi2h0Yx575QBglok++TM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=noL2GwiU; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="noL2GwiU" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9A51BC19423; Tue, 31 Mar 2026 21:28:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1774992527; bh=WJ1MvN8V+hC/HPZfDG3Jxx2eF+NqyWJKvekF+n3PMXc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=noL2GwiUMmJXMFUKQbYRlFByI6TziVZXDiNtIbtGUXzQXIgWdD3oxEKF4EgcZDzKk ec4xchchqX2Y3+AiukKKCdijWdRfJII/XIwM/4wC5nWBVlr6YqyNryBMoYUHYMPWUc cC3+d6QVY1WsWbCT9KhvMTZWQiJ3TDEOmYCfg1nRi3qSJ+fBYPh4Cqs2avpTj1nlAA mSbdSFnZ5mOd2/aD36zr2laNrb4JNG/9mnM3aqTK7rGy+CEjk5u2bQlMQrL6QbCP6A SnEdkVnYgC7V6Mb5sXDAge6eq13KyGltfxEutcVUswGEie/ndFWkV30w4q8K6jdZyt y0ev+ASs885+g== From: Andrey Albershteyn To: linux-xfs@vger.kernel.org, fsverity@lists.linux.dev, linux-fsdevel@vger.kernel.org, ebiggers@kernel.org Cc: Andrey Albershteyn , hch@lst.de, linux-ext4@vger.kernel.org, linux-f2fs-devel@lists.sourceforge.net, linux-btrfs@vger.kernel.org, djwong@kernel.org Subject: [PATCH v6 04/22] fsverity: pass digest size and hash of the empty block to ->write Date: Tue, 31 Mar 2026 23:28:05 +0200 Message-ID: <20260331212827.2631020-5-aalbersh@kernel.org> X-Mailer: git-send-email 2.51.2 In-Reply-To: <20260331212827.2631020-1-aalbersh@kernel.org> References: <20260331212827.2631020-1-aalbersh@kernel.org> Precedence: bulk X-Mailing-List: linux-btrfs@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Let filesystem iterate over hashes in the block and check if these are hashes of zeroed data blocks. XFS will use this to decide if it want to store tree block full of these hashes. Signed-off-by: Andrey Albershteyn Reviewed-by: "Darrick J. Wong" --- fs/btrfs/verity.c | 6 +++++- fs/ext4/verity.c | 4 +++- fs/f2fs/verity.c | 4 +++- fs/verity/enable.c | 4 +++- include/linux/fsverity.h | 6 +++++- 5 files changed, 19 insertions(+), 5 deletions(-) diff --git a/fs/btrfs/verity.c b/fs/btrfs/verity.c index 0062b3a55781..6d8d3808d75d 100644 --- a/fs/btrfs/verity.c +++ b/fs/btrfs/verity.c @@ -773,11 +773,15 @@ static struct page *btrfs_read_merkle_tree_page(struct inode *inode, * @buf: Merkle tree block to write * @pos: the position of the block in the Merkle tree (in bytes) * @size: the Merkle tree block size (in bytes) + * @zero_digest: the hash of a merkle block-sized buffer of zeroes + * @digest_size: size of zero_digest, in bytes * * Returns 0 on success or negative error code on failure */ static int btrfs_write_merkle_tree_block(struct file *file, const void *buf, - u64 pos, unsigned int size) + u64 pos, unsigned int size, + const u8 *zero_digest, + unsigned int digest_size) { struct inode *inode = file_inode(file); loff_t merkle_pos = merkle_file_pos(inode); diff --git a/fs/ext4/verity.c b/fs/ext4/verity.c index ca61da53f313..347945ac23a4 100644 --- a/fs/ext4/verity.c +++ b/fs/ext4/verity.c @@ -374,7 +374,9 @@ static void ext4_readahead_merkle_tree(struct inode *inode, pgoff_t index, } static int ext4_write_merkle_tree_block(struct file *file, const void *buf, - u64 pos, unsigned int size) + u64 pos, unsigned int size, + const u8 *zero_digest, + unsigned int digest_size) { pos += ext4_verity_metadata_pos(file_inode(file)); diff --git a/fs/f2fs/verity.c b/fs/f2fs/verity.c index 92ebcc19cab0..b3b3e71604ac 100644 --- a/fs/f2fs/verity.c +++ b/fs/f2fs/verity.c @@ -270,7 +270,9 @@ static void f2fs_readahead_merkle_tree(struct inode *inode, pgoff_t index, } static int f2fs_write_merkle_tree_block(struct file *file, const void *buf, - u64 pos, unsigned int size) + u64 pos, unsigned int size, + const u8 *zero_digest, + unsigned int digest_size) { pos += f2fs_verity_metadata_pos(file_inode(file)); diff --git a/fs/verity/enable.c b/fs/verity/enable.c index 42dfed1ce0ce..ad4ff71d7dd9 100644 --- a/fs/verity/enable.c +++ b/fs/verity/enable.c @@ -50,7 +50,9 @@ static int write_merkle_tree_block(struct file *file, const u8 *buf, int err; err = inode->i_sb->s_vop->write_merkle_tree_block(file, buf, pos, - params->block_size); + params->block_size, + params->zero_digest, + params->digest_size); if (err) fsverity_err(inode, "Error %d writing Merkle tree block %lu", err, index); diff --git a/include/linux/fsverity.h b/include/linux/fsverity.h index 03f703e5bb40..881db75f1cba 100644 --- a/include/linux/fsverity.h +++ b/include/linux/fsverity.h @@ -124,6 +124,8 @@ struct fsverity_operations { * @buf: the Merkle tree block to write * @pos: the position of the block in the Merkle tree (in bytes) * @size: the Merkle tree block size (in bytes) + * @zero_digest: the hash of a merkle block-sized buffer of zeroes + * @digest_size: size of zero_digest, in bytes * * This is only called between ->begin_enable_verity() and * ->end_enable_verity(). @@ -131,7 +133,9 @@ struct fsverity_operations { * Return: 0 on success, -errno on failure */ int (*write_merkle_tree_block)(struct file *file, const void *buf, - u64 pos, unsigned int size); + u64 pos, unsigned int size, + const u8 *zero_digest, + unsigned int digest_size); }; #ifdef CONFIG_FS_VERITY -- 2.51.2