From patchwork Sat Dec 14 03:10:40 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Chamberlain X-Patchwork-Id: 13908296 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 75B811401C; Sat, 14 Dec 2024 03:10:58 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=198.137.202.133 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734145862; cv=none; b=NLphXPXRJO1cP2GadUHCVXzngjv7O04FbheJtgLAxj4rsV/5sOYsI7/LQTxqMkokKxC0ce5SbkSkD7lm5a4VxAwFrFG67MLQmKDYQ7Mnyf2OWZC+ubK9YveBKZiqh2axCajJyK0Szqh+XdpcXdz/B6C8Aw0kkZApiKEHoSaRYfY= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1734145862; c=relaxed/simple; bh=vEzp21Qt7bdEDcirqhV48PHN9Uws+42ZUaIYtjNb4MQ=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=oifTes4WWaSRADvou6hC1epjZHeqcKpYYhxxp21Lu0/k65iGMcARlk2C0xOl8sS0nVRnZB4dn/1GEn6Guy4sz043Qxj/Z8iX5tBsQA8VzMpFsOWOEb98qMMflYcycOhUDr0IOkln9kTIVBbBy4b+KgYG43JQJNeq/kzIbrGxAPc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=kernel.org; spf=none smtp.mailfrom=infradead.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b=y+Vot3PJ; arc=none smtp.client-ip=198.137.202.133 Authentication-Results: smtp.subspace.kernel.org; dmarc=fail (p=quarantine dis=none) header.from=kernel.org Authentication-Results: smtp.subspace.kernel.org; spf=none smtp.mailfrom=infradead.org Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=infradead.org header.i=@infradead.org header.b="y+Vot3PJ" DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; h=Sender:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Reply-To:Content-Type:Content-ID:Content-Description; bh=ly9Z0m8eTHU3wfdp35JFAoonrPj9YJ5xpu33d2EAXi4=; b=y+Vot3PJozFxtHqZ7Fp9JDbo4c jsrflL/YvKop7QmnivqVS3/9cSOrtdNg1NZt87O4y3Fo0P3YmFEh9/6/z11Ef8JQPkW11UbAml0SX dB33hD26ixC0mXy6W9q36zaEDrc+EuP2Gay4kESD2wcM+A4tuvYvCRryQz1gZrGPfX6i8p2pffDWZ DouswSptmAW/mI1zWobDfnT0kYB+yzVgSHn87hRfSub8MYVWaJdRL+WpipyflNXZIoh8fl/YQ4MMU hxiYm95uqF/bNOR2mx96TdbdT1NVHq4GImAWGKf8IHWbdAstSa0ejAnvTpz9mLIlOtxuybuU1h404 JfGexPMg==; Received: from mcgrof by bombadil.infradead.org with local (Exim 4.98 #2 (Red Hat Linux)) id 1tMIYN-00000005c3Z-3ONS; Sat, 14 Dec 2024 03:10:51 +0000 From: Luis Chamberlain To: willy@infradead.org, hch@lst.de, hare@suse.de, dave@stgolabs.net, david@fromorbit.com, djwong@kernel.org Cc: john.g.garry@oracle.com, ritesh.list@gmail.com, kbusch@kernel.org, linux-fsdevel@vger.kernel.org, linux-xfs@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org, gost.dev@samsung.com, p.raghav@samsung.com, da.gomez@samsung.com, kernel@pankajraghav.com, mcgrof@kernel.org Subject: [RFC v2 02/11] fs/buffer: add a for_each_bh() for block_read_full_folio() Date: Fri, 13 Dec 2024 19:10:40 -0800 Message-ID: <20241214031050.1337920-3-mcgrof@kernel.org> X-Mailer: git-send-email 2.47.1 In-Reply-To: <20241214031050.1337920-1-mcgrof@kernel.org> References: <20241214031050.1337920-1-mcgrof@kernel.org> Precedence: bulk X-Mailing-List: linux-block@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Sender: Luis Chamberlain We want to be able to work through all buffer heads on a folio for an async read, but in the future we want to support the option to stop before we've processed all linked buffer heads. To make code easier to read and follow adopt a for_each_bh(tmp, head) loop instead of using a do { ... } while () to make the code easier to read and later be expanded in subsequent patches. This introduces no functional changes. Signed-off-by: Luis Chamberlain Reviewed-by: Hannes Reinecke --- fs/buffer.c | 18 +++++++++++++++--- 1 file changed, 15 insertions(+), 3 deletions(-) diff --git a/fs/buffer.c b/fs/buffer.c index 580451337efa..108e1c36fc1a 100644 --- a/fs/buffer.c +++ b/fs/buffer.c @@ -2392,6 +2392,17 @@ static void bh_read_batch_async(struct folio *folio, } } +#define bh_is_last(__bh, __head) ((__bh)->b_this_page == (__head)) + +#define bh_next(__bh, __head) \ + (bh_is_last(__bh, __head) ? NULL : (__bh)->b_this_page) + +/* Starts from the provided head */ +#define for_each_bh(__tmp, __head) \ + for ((__tmp) = (__head); \ + (__tmp); \ + (__tmp) = bh_next(__tmp, __head)) + /* * Generic "read_folio" function for block devices that have the normal * get_block functionality. This is most of the block device filesystems. @@ -2421,11 +2432,10 @@ int block_read_full_folio(struct folio *folio, get_block_t *get_block) iblock = div_u64(folio_pos(folio), blocksize); lblock = div_u64(limit + blocksize - 1, blocksize); - bh = head; nr = 0; i = 0; - do { + for_each_bh(bh, head) { if (buffer_uptodate(bh)) continue; @@ -2454,7 +2464,9 @@ int block_read_full_folio(struct folio *folio, get_block_t *get_block) continue; } arr[nr++] = bh; - } while (i++, iblock++, (bh = bh->b_this_page) != head); + i++; + iblock++; + } bh_read_batch_async(folio, nr, arr, fully_mapped, nr == 0, page_error);