From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Cyrus-Session-Id: sloti22d1t05-1722532-1521560346-2-358291713821875593 X-Sieve: CMU Sieve 3.0 X-Spam-known-sender: no X-Spam-score: 0.0 X-Spam-hits: BAYES_00 -1.9, HEADER_FROM_DIFFERENT_DOMAINS 0.25, ME_NOAUTH 0.01, RCVD_IN_DNSWL_HI -5, T_RP_MATCHES_RCVD -0.01, LANGUAGES en, BAYES_USED global, SA_VERSION 3.4.0 X-Spam-source: IP='209.132.180.67', Host='vger.kernel.org', Country='CN', FromHeader='de', MailFrom='org' X-Spam-charsets: plain='us-ascii' X-Resolved-to: greg@kroah.com X-Delivered-to: greg@kroah.com X-Mail-from: linux-api-owner@vger.kernel.org ARC-Seal: i=1; a=rsa-sha256; cv=none; d=messagingengine.com; s=arctest; t=1521560345; b=XcjtCqM/4O/NzAyvB590PfFLoF55aAUZl7hqFA8FMqOxF7c kHsaZtwHNz8yBrD8/bhg7gI0W2/yz/Xh2ycyRTte9OrgmBjjhnTlXPo63tFd9pT8 LcNvBb9z7m5MqlOKH2UUEeT1Ai6P3fxQGOHcht/FmdPnwJJbiFNt/LBXW82xv/he YCzpzwMmRmZplPNXuGTp3mGmqGBbl5H3S4x4OISqlXVczNGRsv8QZf5ff+qx23Tr LsY5kd87A/zfNITKsKgLsUjUTb2IjBhBC9a3wP/mJtrVdEJ6Z6o0ct+gDgPaOfGk 9KcZbo0egsIPTcKyvCqmHI1fEHxhOLZqT7bCz1A== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d= messagingengine.com; h=date:from:to:cc:subject:message-id :references:mime-version:content-type:in-reply-to:sender :list-id; s=arctest; t=1521560345; bh=+rk5jYJ+akbSxItmNX3FCrRxV8 oZFU96yMCmmPX68Mc=; b=PZWtNDKSy0cMdiMJZSnlfPtScFdjkzze5njvaTSX4U Cp2+StHM8zuUusKxdLbHuerJ7zlxwOTNowJv1bq5EMWUCju67WnWDOo+ubolYTe/ NUD9UTnnHr887gacQlHZXXXaIVaw5e0AVGxOYO0PtsjLVRm1ViN3z15W476WnPYv OYF8KglJL2ONkIJIrk6YxRTJrUDsb8NOkw4WUv19SxavAPh9G4SfUkMpXMMa5AKe ujabzMHZkesdR2vdp4XSUhULjUtE//83hgstbDkk9HRAh/YyqZ1nN0VegWO+2c+Y mzxoge0WgKYdPl4hLchA0LkgO9TajqPxGp4yiKSwZM1Q== ARC-Authentication-Results: i=1; mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=lst.de; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=lst.de header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 Authentication-Results: mx3.messagingengine.com; arc=none (no signatures found); dkim=none (no signatures found); dmarc=none (p=none,has-list-id=yes,d=none) header.from=lst.de; iprev=pass policy.iprev=209.132.180.67 (vger.kernel.org); spf=none smtp.mailfrom=linux-api-owner@vger.kernel.org smtp.helo=vger.kernel.org; x-aligned-from=fail; x-ptr=pass x-ptr-helo=vger.kernel.org x-ptr-lookup=vger.kernel.org; x-return-mx=pass smtp.domain=vger.kernel.org smtp.result=pass smtp_org.domain=kernel.org smtp_org.result=pass smtp_is_org_domain=no header.domain=lst.de header.result=pass header_is_org_domain=yes; x-vs=clean score=-100 state=0 X-ME-VSCategory: clean Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751186AbeCTPjD (ORCPT ); Tue, 20 Mar 2018 11:39:03 -0400 Received: from verein.lst.de ([213.95.11.211]:37798 "EHLO newverein.lst.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751628AbeCTPjC (ORCPT ); Tue, 20 Mar 2018 11:39:02 -0400 Date: Tue, 20 Mar 2018 16:39:00 +0100 From: Christoph Hellwig To: "Darrick J. Wong" Cc: Christoph Hellwig , viro@zeniv.linux.org.uk, Avi Kivity , linux-aio@kvack.org, linux-fsdevel@vger.kernel.org, netdev@vger.kernel.org, linux-api@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 13/36] fs: introduce new ->get_poll_head and ->poll_mask methods Message-ID: <20180320153900.GA24355@lst.de> References: <20180305212743.16664-1-hch@lst.de> <20180305212743.16664-14-hch@lst.de> <20180320032938.GK7282@magnolia> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20180320032938.GK7282@magnolia> User-Agent: Mutt/1.5.17 (2007-11-01) Sender: linux-api-owner@vger.kernel.org X-Mailing-List: linux-api@vger.kernel.org X-getmail-retrieved-from-mailbox: INBOX X-Mailing-List: linux-kernel@vger.kernel.org List-ID: On Mon, Mar 19, 2018 at 08:29:38PM -0700, Darrick J. Wong wrote: > On Mon, Mar 05, 2018 at 01:27:20PM -0800, Christoph Hellwig wrote: > > ->get_poll_head returns the waitqueue that the poll operation is going > > to sleep on. Note that this means we can only use a single waitqueue > > for the poll, unlike some current drivers that use two waitqueues for > > different events. But now that we have keyed wakeups and heavily use > > those for poll there aren't that many good reason left to keep the > > multiple waitqueues, and if there are any ->poll is still around, the > > driver just won't support aio poll. > > > > Signed-off-by: Christoph Hellwig > > I've been wondering, how does a regular filesystem connect with this? In general, it doesn't. In Unix regular files aren't pollable. > Also, does anything implement get_poll_head? It looks to me like an aio > poll provider has to provide both... Yes. Everyone who implements ->poll_mask also needs to implement get_poll_head. For sockets we just happen to be able to use a generic implementation in net/socket.c for most of them.