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 1E6E3C7EE30 for ; Mon, 27 Feb 2023 13:36:13 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id AC7526B0072; Mon, 27 Feb 2023 08:36:12 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id A772F6B0073; Mon, 27 Feb 2023 08:36:12 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 93F2A6B0074; Mon, 27 Feb 2023 08:36:12 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0014.hostedemail.com [216.40.44.14]) by kanga.kvack.org (Postfix) with ESMTP id 86AE86B0072 for ; Mon, 27 Feb 2023 08:36:12 -0500 (EST) Received: from smtpin11.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay10.hostedemail.com (Postfix) with ESMTP id 4D9F2C09FB for ; Mon, 27 Feb 2023 13:36:12 +0000 (UTC) X-FDA: 80513170584.11.7A6D590 Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) by imf07.hostedemail.com (Postfix) with ESMTP id 10B0E40003 for ; Mon, 27 Feb 2023 13:36:08 +0000 (UTC) Authentication-Results: imf07.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b="U2/4vAGp"; spf=none (imf07.hostedemail.com: domain of BATV+2f91113c06227fb51968+7127+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+2f91113c06227fb51968+7127+infradead.org+hch@bombadil.srs.infradead.org; dmarc=none ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1677504969; 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=ePxJvQ0KvUvm6Gs3BEG2jGn/1JJyaeylcAdC0Se4Ji0=; b=j1SZ/pDk9DdIJ6oxOXpsHGAUna8JRb1qsnxankcUgc/el89itQTmZieXHOVDE4lXpwj2Uh oGqfk0uZ3SeItKc7lUKpsh5L59yYQZDng9x/WZbkAxlK0IeS/gbbULpbP2Ecr6QtcTjNys WeIbpNQTiJhKuETUBBzgsjzG5a0jjIg= ARC-Authentication-Results: i=1; imf07.hostedemail.com; dkim=pass header.d=infradead.org header.s=bombadil.20210309 header.b="U2/4vAGp"; spf=none (imf07.hostedemail.com: domain of BATV+2f91113c06227fb51968+7127+infradead.org+hch@bombadil.srs.infradead.org has no SPF policy when checking 198.137.202.133) smtp.mailfrom=BATV+2f91113c06227fb51968+7127+infradead.org+hch@bombadil.srs.infradead.org; dmarc=none ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1677504969; a=rsa-sha256; cv=none; b=HmmDbEyQmUKwHUGrmQq4zIvI1JD192YURHJumIkZE9mNEmZJpSyP896KeA2RA4sQEoC4Jf r8o1tp9YbTrlIG4vMNosTFkUV91WOKtBsgqqDvMUYNv0NWCXPkApcr50v3V3jpsSKYAgXP 2H3AkOTj8HjxIFUnIz1u1b3XWxivptM= DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=infradead.org; s=bombadil.20210309; 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=ePxJvQ0KvUvm6Gs3BEG2jGn/1JJyaeylcAdC0Se4Ji0=; b=U2/4vAGppTQb5yg/PqcAw3t8X7 ftdPHbVBPAiuG4E/LOiPNZoOvf6l0815AuKYdGC3QmWjWGctvptLtAsv2S9RxouqY7uFQoPX2ipY7 iXseEHajV+FeRSf+3M8mejeyW8eZFiMzhVwoILXXaf8WskHNWkx2fNnP3LHxEA2sjJK1j2jtbzoai ro1gFu0qDUTlNe1u2bnUc4fEaQgq+F4GkN/LzmKRUUdGC3doMBcKNKbSu/SA/GMvtr4qB/tlTIxKt vbOevMLT8VxCtN5I3i/ID3HNnbUAE5OdL8EwS65BgOqIcfqg2vEOGIWzH/AVz6GJzDBLzIObNY0eV l6AexNzA==; Received: from hch by bombadil.infradead.org with local (Exim 4.94.2 #2 (Red Hat Linux)) id 1pWdfg-009mhW-Ep; Mon, 27 Feb 2023 13:36:04 +0000 Date: Mon, 27 Feb 2023 05:36:04 -0800 From: Christoph Hellwig To: Jan Kara Cc: Christoph Hellwig , Dave Chinner , linux-fsdevel@vger.kernel.org, linux-block@vger.kernel.org, linux-mm@kvack.org, John Hubbard , David Howells , David Hildenbrand Subject: Re: [PATCH 4/5] block: Add support for bouncing pinned pages Message-ID: References: <20230209121046.25360-1-jack@suse.cz> <20230209123206.3548-4-jack@suse.cz> <20230214135604.s5bygnthq7an5eoo@quack3> <20230215045952.GF2825702@dread.disaster.area> <20230216123316.vkmtucazg33vidzg@quack3> <20230227113926.jr7wuhmiul7346as@quack3> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20230227113926.jr7wuhmiul7346as@quack3> X-SRS-Rewrite: SMTP reverse-path rewritten from by bombadil.infradead.org. See http://www.infradead.org/rpr.html X-Stat-Signature: pt8iir35aj7fo6nnchgpgwjjcdoi4us3 X-Rspam-User: X-Rspamd-Queue-Id: 10B0E40003 X-Rspamd-Server: rspam06 X-HE-Tag: 1677504968-321452 X-HE-Meta: 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 nVJPxIL8 vlt2rgMT9rtBVU3/ewf0sW6k+6Nw6ToT3P36FXRLixtFx3akNiHjb5Yv93TW3jl2QKvRQUeD8kjgkVg7VV89S3L+/bd3jlZc1upfUvvJuovOVqrFwpkZbGdNB6a8altE7xlvSyQ531dVEOVxpbOQ23oFd++lI4r/ZB4Bdzcf+ym3YsE+wiTYN4vSuP7tE2gB7dgCrf3DBgOby9hHkSIXbwXpkQP4046cmtLS1vK/fqdCXIvX88pD8g6OmXpAQCDQbh5Iykuah8AZuDibjVW5TNhvug6Ojcs3HXmDUpHVhI4nWoJQtqyXU4XBCjyJcz2aEmbjz4XQfmiwM1EXnrpY8Q++1RyPevU6hGCl7uo0msQ4GnHlPnyTQ1sMbB4ICFmSSUVzPy0vmJi8Xlg0mq+WLRMdamw== 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 Mon, Feb 27, 2023 at 12:39:26PM +0100, Jan Kara wrote: > Do you mean to copy these pages on fsync(2) to newly allocated buffer and > then submit it via direct IO? That looks sensible to me. We could then make > writeback path just completely ignore these long term pinned pages and just > add this copying logic into filemap_fdatawrite() or something like that. I don't think we'd even have to copy them on fsync. Just do an in-kernel ITER_BVEC direct I/O on them. The only hard part would be to come up with a way to skip the pagecache invalidation and writeout for these I/Os.