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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 4B831C64EC4 for ; Fri, 3 Mar 2023 16:53:05 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id C3B496B0071; Fri, 3 Mar 2023 11:53:04 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id BEAED6B0075; Fri, 3 Mar 2023 11:53:04 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id AB3A76B0078; Fri, 3 Mar 2023 11:53:04 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0017.hostedemail.com [216.40.44.17]) by kanga.kvack.org (Postfix) with ESMTP id 9BE346B0071 for ; Fri, 3 Mar 2023 11:53:04 -0500 (EST) Received: from smtpin25.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay02.hostedemail.com (Postfix) with ESMTP id 6299412034F for ; Fri, 3 Mar 2023 16:53:04 +0000 (UTC) X-FDA: 80528181888.25.2F7792F Received: from dfw.source.kernel.org (dfw.source.kernel.org [139.178.84.217]) by imf11.hostedemail.com (Postfix) with ESMTP id 9E43C40019 for ; Fri, 3 Mar 2023 16:53:02 +0000 (UTC) Authentication-Results: imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=Fy8mUh8E; spf=pass (imf11.hostedemail.com: domain of djwong@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=djwong@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1677862382; h=from:from:sender:reply-to:subject:subject:date:date: message-id:message-id:to:to:cc:cc:mime-version:mime-version: content-type:content-type:content-transfer-encoding: in-reply-to:in-reply-to:references:references:dkim-signature; bh=eoI/LEdWEv7NG4rj8150+lmtowxwr/+sEZvxrqibv00=; b=JwJysBDpjy58n9sE/o5DR7eh4c9GjdbYjANvZK/n78g8OMLjhoaFpKvDHG6W2mhA7lYpdm 6+nrEeD5JBgBXFjVrgddNOJrKKzzGjAOYrl6uO8U+MT7UQ4Zetnh3yallWHfMcovtFha5I UlNKWqEaXqcSzXlBtPRRaFNEEX3CnGQ= ARC-Authentication-Results: i=1; imf11.hostedemail.com; dkim=pass header.d=kernel.org header.s=k20201202 header.b=Fy8mUh8E; spf=pass (imf11.hostedemail.com: domain of djwong@kernel.org designates 139.178.84.217 as permitted sender) smtp.mailfrom=djwong@kernel.org; dmarc=pass (policy=none) header.from=kernel.org ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1677862382; a=rsa-sha256; cv=none; b=1tCxRWKjX8ynEr4ONd1bsQ3tFOpvF/cgCWz0SehaGHr9X6aQxpyaEIC8nfWwhyHxUapCKt n2RTHs1oOkN4miipeP2ivkgfFUk5aMvCsSAFn2NZkx48VSdJm5BUG5qGLiDHiFngQKEf0o nnxikfDQ6zhPQMwU1Vp4mXI7k3Ok3Pk= Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by dfw.source.kernel.org (Postfix) with ESMTPS id 92E3761840; Fri, 3 Mar 2023 16:53:01 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id EAF03C433EF; Fri, 3 Mar 2023 16:53:00 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1677862381; bh=2/MxGsA+UeJoeA0qwShKf6lp6y22SPH559LMbaOGOUc=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=Fy8mUh8ElUxKUrQu+GRfoNvC6ZR30x5Qv1MpnJHepd3jPizO5xu0Av5rz58V1z2c1 wSGjGASRIwKn7tYhJUGFdludgRmW7l4z7zUljb+qMLenmvY/HLlhjciprzRwsw0Xx6 KT05LR8AGH5lNYPhT6xuVBXLBVbi/vAMWIFb91Wi+TfsASsGP+3aTQKA2e+P8ped8N KULknt2iIyjBpzgHFg/ReRS34jeBtxky9u4iTD3M/T2XoZNNRFBCveAqlK4pB5GbFf E0RBumj48mLkl4U2UhehD1j75tWcTryyJOHJJ11UL30aj4gn/ObA/d+jErlQxW5eJs nALyEce2ffbbA== Date: Fri, 3 Mar 2023 08:53:00 -0800 From: "Darrick J. Wong" To: Matthew Wilcox Cc: Stefan Roesch , io-uring@vger.kernel.org, kernel-team@fb.com, linux-mm@kvack.org, linux-xfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, david@fromorbit.com, jack@suse.cz, hch@infradead.org, axboe@kernel.dk, Christoph Hellwig Subject: Re: [RESEND PATCH v9 04/14] iomap: Add flags parameter to iomap_page_create() Message-ID: References: <20220623175157.1715274-1-shr@fb.com> <20220623175157.1715274-5-shr@fb.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Stat-Signature: 9o6icwy7i3438rcqb1f1xqb7je8u4asy X-Rspam-User: X-Rspamd-Queue-Id: 9E43C40019 X-Rspamd-Server: rspam06 X-HE-Tag: 1677862382-692264 X-HE-Meta: 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 jYYvbRsi m4WaEtIH57WY2xA+FhKDXBZ1nNAG6zb0fh0tdXPpCYt3NiljKtei5pyfQwhubnJcXfXLcHQbBSA8XT4iCMR/OCzougYfb6jWko1dfzBzb9VFCu2/n3g6wlmjz0iaP1uKo4DYqSn7p1g63D68/CT8cWnKDtEKPyvd8dkV/2uLNMKfD7ltxXHYAiZ+Tx5L+5celdwayd1BGX2RKLR68TIwts32XCXxCWgY4P9b6bXY/FT2sjOB6Cw+Xx3y1IwI0qx23+Dk7xvCqC5Fm5QBANnrN2QS+zxoopIJ7YdyZOq09HLAXlPFLF/F0m5tOaI9pjx7fjG+ByYWvmdY4Mzt059e2nd5aZygwD3noW/grkOf0s8lR0GzshS2c0nAP0vvjp9E5uZh4fWTrltKTaYc= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Fri, Mar 03, 2023 at 04:51:10AM +0000, Matthew Wilcox wrote: > On Thu, Jun 23, 2022 at 10:51:47AM -0700, Stefan Roesch wrote: > > Add the kiocb flags parameter to the function iomap_page_create(). > > Depending on the value of the flags parameter it enables different gfp > > flags. > > > > No intended functional changes in this patch. > > [...] > > > @@ -226,7 +234,7 @@ static int iomap_read_inline_data(const struct iomap_iter *iter, > > if (WARN_ON_ONCE(size > iomap->length)) > > return -EIO; > > if (offset > 0) > > - iop = iomap_page_create(iter->inode, folio); > > + iop = iomap_page_create(iter->inode, folio, iter->flags); > > else > > iop = to_iomap_page(folio); > > I really don't like what this change has done to this file. I'm > modifying this function, and I start thinking "Well, hang on, if > flags has IOMAP_NOWAIT set, then GFP_NOWAIT can fail, and iop > will be NULL, so we'll end up marking the entire folio uptodate > when really we should only be marking some blocks uptodate, so > we should really be failing the entire read if the allocation > failed, but maybe it's OK because IOMAP_NOWAIT is never set in > this path". > > I don't know how we fix this. Maybe return ERR_PTR(-ENOMEM) or > -EAGAIN if the memory allocation fails (leaving the NULL return > for "we don't need an iop"). Thoughts? I don't see any problem with that, aside from being pre-coffee and on vacation for the rest of today. ;) --D