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 C5CECC46CD2 for ; Sat, 27 Jan 2024 17:57:54 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id E393A6B0071; Sat, 27 Jan 2024 12:57:53 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id DC21C6B0072; Sat, 27 Jan 2024 12:57:53 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id C63416B0074; Sat, 27 Jan 2024 12:57:53 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from relay.hostedemail.com (smtprelay0013.hostedemail.com [216.40.44.13]) by kanga.kvack.org (Postfix) with ESMTP id B017D6B0071 for ; Sat, 27 Jan 2024 12:57:53 -0500 (EST) Received: from smtpin18.hostedemail.com (a10.router.float.18 [10.200.18.1]) by unirelay01.hostedemail.com (Postfix) with ESMTP id 5E8DF1C0EA2 for ; Sat, 27 Jan 2024 17:57:53 +0000 (UTC) X-FDA: 81725849226.18.2D529F1 Received: from out-182.mta1.migadu.com (out-182.mta1.migadu.com [95.215.58.182]) by imf05.hostedemail.com (Postfix) with ESMTP id 6233C100014 for ; Sat, 27 Jan 2024 17:57:51 +0000 (UTC) Authentication-Results: imf05.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=BPHwnowD; spf=pass (imf05.hostedemail.com: domain of kent.overstreet@linux.dev designates 95.215.58.182 as permitted sender) smtp.mailfrom=kent.overstreet@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=hostedemail.com; s=arc-20220608; t=1706378271; 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=8FnooJCWSxpBQ7kJMIzkrQtNeGdttnkRA9KqDLumr+o=; b=dHzaRcCS57mmN6lvUu8D0/PF2YyCwkbS/Kq6vnxeftiH5uqqjD5daE8Q/dY12hWTqDXePn xtGf7Fjeguki41dFmNvfq3uv13NKRmwJ+RuXv8Yzn3qm+mshuhO1PwSmaulNZtc0oRojbv /DkzVlCRdApYrwaD0xWIqA/FX8gxE64= ARC-Authentication-Results: i=1; imf05.hostedemail.com; dkim=pass header.d=linux.dev header.s=key1 header.b=BPHwnowD; spf=pass (imf05.hostedemail.com: domain of kent.overstreet@linux.dev designates 95.215.58.182 as permitted sender) smtp.mailfrom=kent.overstreet@linux.dev; dmarc=pass (policy=none) header.from=linux.dev ARC-Seal: i=1; s=arc-20220608; d=hostedemail.com; t=1706378271; a=rsa-sha256; cv=none; b=pYCIBQ3sudz4OWLU/u0v93i3nkqnH+LCCWdyK3PP2Ts0/E77mZL67Dtw+Z/Tq1wiVKi1T3 5Hf7HWu8axao9f6fRUIqj6Jrop6ZvuiLFCHs83mxRSLc9ZlrM/IayxFwLIWAiudPxrwZTm vRsx6cX3WnDuUorHGWUpvH6fWafQmTg= Date: Sat, 27 Jan 2024 12:57:45 -0500 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1706378269; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=8FnooJCWSxpBQ7kJMIzkrQtNeGdttnkRA9KqDLumr+o=; b=BPHwnowDbG/6r6CMDf/n/61SkvEjYVDhLgXNOaJA00LRzmXdeRPz07+gcZ+jOsDy6VWYQE AYvU1rYFNEjCL6IwxbYd7ffEaJ3JTrWQbcpNjsYzZBHI8QqIdQPkgU10XZ1H+ldxBB0NRt bk7XNBThQEMD8l6RHs2aDybHQfjhkys= X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. From: Kent Overstreet To: Matthew Wilcox Cc: lsf-pc@lists.linux-foundation.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-block@vger.kernel.org, linux-ide@vger.kernel.org, linux-scsi@vger.kernel.org, linux-nvme@lists.infradead.org, bpf@vger.kernel.org Subject: Re: [LSF/MM/BPF TOPIC] State Of The Page Message-ID: References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Migadu-Flow: FLOW_OUT X-Rspamd-Queue-Id: 6233C100014 X-Rspam-User: X-Stat-Signature: haumuoa4fwr74cn3xugjitykshkk9zig X-Rspamd-Server: rspam01 X-HE-Tag: 1706378271-66448 X-HE-Meta: U2FsdGVkX18ZAtwYK4egSWikHgPG4AFjywxqTB1GTgas9ZEHrrXdxfuWTGanrSdgbc39z9ciKOwHEKRY7qTZhtGxC3YF3yq59CvcbwD9yZGbiDyFut3Gc33pXRIABLQXJapDcQGORLz64Bhp1OGawQC0tbgOcD7rudTdWaqmgbbiyIez5Ky+p7KxZh4hPQZQL7MqqeSx11Syq2mcsMn33SLCuqMeXvMwloxu1l5bknEC1B5P9Ss676jaWQwNQyBA20zJ8sq+zVuEv8Rp39jLl0ltWMFoynVzgqdGGVd2Z4LiYaqoJBM7wITcRHldwu3jLH5XNwYFkWDWM3dz91ykZdRnUgslk+bNHHQ1VIcIB2UslovU2Ik1NXAP7BwNhEVJ04DRhvlp6WxvqYlgF/JiC46ThGsdpZj7KP8aWGXUmD2sNamWZtLIpzM4r4+NR8XfzspQz1jBf/tY4l2WUR9sujrcj+NM4q60NK3EwfpN8DDiy86Eqtnz0wJI+HxC/F1uxT4eGBUJLQDgxnH7+YT6zd/mnClfcpQ5K7/YJmI9TPEPl7mp7vfVGmMcVk2hrO3KLqWbXOtcLsMoGqxPeCTlvHomMFfwwt42qrwdWtdewar6tW20/GlJ1irSxXVkO1SmVt9ZmpjTLTrzAgurDLImxpSuOfFalZ5WIMH3sMgaej8UeuMUb2asaGc1i0livZL+ArxN5Na+3TADXvRCTxaao7vsLK/R48Ckw+Cgz0D7Kprr57EGwqkSPbF0DQk+kbAH/zIy3tk+Ue5Os19clbRev0E38t28P/6FO6onaEp6dc6Mn//fhMtkmMXeNwtdqN1DGHcGqclB/pegB3hv+vPg/RQhv23aT//YsEBrv7ROhCjPuUvPbXR2LdqLFA2rMG6XunTs2LTlvFieychW0auMcpuYz/NU/2SMD65aEFfGMYv1vEbxpJJK8dsZknnwV/p4Acxt4uiHOiu1+JSBvjv bFBKNOUA iQcV5/ns+7ZAK/nKcCySzZf7jvbqYU0V0AWAixOWISQFg5Qtq10XDQKvxRdIQp7P501jI0PvQHccXJ83GlBzjBhbHysNZGNv1BMGAdrNQjEKPQLE= X-Bogosity: Ham, tests=bogofilter, spamicity=0.008091, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On Fri, Jan 19, 2024 at 04:24:29PM +0000, Matthew Wilcox wrote: > - What are we going to do about bio_vecs? For bios and biovecs, I think it's important to keep in mind the distinction between the code that owns and submits the bio, and the consumer underneath. The code underneath could just as easily work with pfns, and the code above got those pages from somewhere else, so it doesn't _need_ the bio for access to those pages/folios (it would be a lot of refactoring though). But I've been thinking about going in a different direction - what if we unified iov_iter and bio? We've got ~3 different scatter-gather types that an IO passes through down the stack, and it would be lovely if we could get it down to just one; e.g. for DIO, pinning pages right at the copy_from_user boundary.