From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id BD935C77B78 for ; Fri, 21 Apr 2023 22:50:00 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233758AbjDUWt7 (ORCPT ); Fri, 21 Apr 2023 18:49:59 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:49228 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233754AbjDUWt6 (ORCPT ); Fri, 21 Apr 2023 18:49:58 -0400 Received: from casper.infradead.org (casper.infradead.org [IPv6:2001:8b0:10b:1236::1]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 71F42E60; Fri, 21 Apr 2023 15:49:57 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=casper.20170209; h=In-Reply-To:Content-Type:MIME-Version: References:Message-ID:Subject:Cc:To:From:Date:Sender:Reply-To: Content-Transfer-Encoding:Content-ID:Content-Description; bh=Rk/OYWhW/XAI/I4YNvgkI3t2ZA+2S6o9dTT4l5mLGUU=; b=EDk6d+sAzT9ozbYKqvEeLRubE3 G/qot7oj55X3AiaR2lLLm8yBh8BW3+E56dNXdljzVphWA+lV6sKfQ/0It6JkKoIFogYP5TAtrtu6q i/jd4HkFuKTz2kKi+bKR2g2GByNuISpDskvAbg4Wu/XE4Xgah+lEdR6pdxWq/7QHS0S2peABzdybd qBl9BTxmUjHUI81U7fNU2PXG7Lx4Ef2yGHI7lJZuKxQ/uAYWGjxRoBo/GVDRjTt5mwSwWov9aQBKO RBhTRZHrRSxSccSeyYa41TlJt/1dnR9ZVebBspme9XrLyJMAmQxfE5qxmCe2/UjkutydDYtGSOzYH WS6elVnQ==; Received: from willy by casper.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1ppzZX-00FiQg-N7; Fri, 21 Apr 2023 22:49:43 +0000 Date: Fri, 21 Apr 2023 23:49:43 +0100 From: Matthew Wilcox To: Luis Chamberlain Cc: hughd@google.com, akpm@linux-foundation.org, brauner@kernel.org, djwong@kernel.org, p.raghav@samsung.com, da.gomez@samsung.com, a.manzanares@samsung.com, dave@stgolabs.net, yosryahmed@google.com, keescook@chromium.org, hare@suse.de, kbusch@kernel.org, patches@lists.linux.dev, linux-block@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org Subject: Re: [RFC 4/8] shmem: add helpers to get block size Message-ID: References: <20230421214400.2836131-1-mcgrof@kernel.org> <20230421214400.2836131-5-mcgrof@kernel.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230421214400.2836131-5-mcgrof@kernel.org> Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org On Fri, Apr 21, 2023 at 02:43:56PM -0700, Luis Chamberlain wrote: > struct shmem_sb_info { > +#ifdef CONFIG_TMPFS > + u64 blocksize; > +#endif u64? You're planning on supporting a blocksize larger than 2GB? I would store block_order (in an unsigned char) and then you can avoid the call to ffs(), at the expense of doing 1UL << sbi->block_order;