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 X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH, MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=unavailable autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D7C96C55ABD for ; Fri, 6 Nov 2020 17:22:12 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 75B102078B for ; Fri, 6 Nov 2020 17:22:12 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=ziepe.ca header.i=@ziepe.ca header.b="Z5hliPe4" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727219AbgKFRWL (ORCPT ); Fri, 6 Nov 2020 12:22:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43300 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726010AbgKFRWL (ORCPT ); Fri, 6 Nov 2020 12:22:11 -0500 Received: from mail-qt1-x841.google.com (mail-qt1-x841.google.com [IPv6:2607:f8b0:4864:20::841]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 0FDE7C0613D3 for ; Fri, 6 Nov 2020 09:22:09 -0800 (PST) Received: by mail-qt1-x841.google.com with SMTP id h12so1266219qtc.9 for ; Fri, 06 Nov 2020 09:22:08 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=ziepe.ca; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=Y11rYbDMlG4Jq6y1mMF8XHIQBRgQTi4LgEIfp1+Fy2I=; b=Z5hliPe42ZhsJgIpO8yM/A/BmnWabQMZyxH3x1SujgBdxmpQeo1iLC7dJllfTWrgs+ ckOwCsKncKsZUSkDwm+CRG+PtHOhk6vGyhb3vaWmExO06uZRfYDDy4x0lNtyZAxfIGSF TzNe/ATxzOTxeiv/h6NniXGC8bMAeaQsSamd0SJaMbdJqgcKE7FX8hgittLCSxWN+Hk0 aEVb3jWNuQ84GZTQ7t0z2P0KnBO9475+HL13KJpZeDMWi657ip/5nImwsscD/jRB/6+1 tzYyPHfeLOmV9kq1MtWUFMAFC/4Mt9DF6Qfy0pjFFXFFgIEb7ZfC/ufepIEP0MSbyLqW 1mng== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=Y11rYbDMlG4Jq6y1mMF8XHIQBRgQTi4LgEIfp1+Fy2I=; b=mLxx4G++XEleXNg9ArifMbq/BlTyKwWaOmQWpv83lDPVPOjPLwUbKFASMr8rz3c606 jJoHb3ZQyyIiJJx4yUyRYFu6cPghHqh59SqYR3BgAyrDbUsYia6d2WXaoe7ya1/7OFkG mIHRTxB2EwhZi+KO+Q0V7ST0mEEBlj4WbfXn75JX7ldMK0o8tkAKzKwKzGEuRGqkcqyF G0Gsy1fhrUK70/GMIJPMZPTQjHgnz0eKGJ9RrITmrMrmC8QViYOSTM0CvaTsxuoxe87p wgCwCsQB9MwCDeRNl8xpYof5w06I8A4EghLal7twBSoBDNPkNoF8w1bBdM46xrQSeDtN espw== X-Gm-Message-State: AOAM5303iobNczmVnJxqyBa1rPIkzhq1gnVJnuBpzQ2xi1YasxIwHBtA Xi9p/JHYWfuG4uY5t7nxY3kvlg== X-Google-Smtp-Source: ABdhPJyiYapImJ+Y336x/nMMBsQzuXDQ9V5MrPZLPGSARv/D7dBPhFBvVcl8QNPKfF7/i3znPagsCA== X-Received: by 2002:ac8:4d4d:: with SMTP id x13mr2465811qtv.72.1604683328177; Fri, 06 Nov 2020 09:22:08 -0800 (PST) Received: from ziepe.ca (hlfxns017vw-156-34-48-30.dhcp-dynamic.fibreop.ns.bellaliant.net. [156.34.48.30]) by smtp.gmail.com with ESMTPSA id w45sm942700qtw.96.2020.11.06.09.22.07 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 06 Nov 2020 09:22:07 -0800 (PST) Received: from jgg by mlx with local (Exim 4.94) (envelope-from ) id 1kb5R8-000z7J-TY; Fri, 06 Nov 2020 13:22:06 -0400 Date: Fri, 6 Nov 2020 13:22:06 -0400 From: Jason Gunthorpe To: Logan Gunthorpe Cc: linux-kernel@vger.kernel.org, linux-nvme@lists.infradead.org, linux-block@vger.kernel.org, linux-pci@vger.kernel.org, linux-mm@kvack.org, iommu@lists.linux-foundation.org, Stephen Bates , Christoph Hellwig , Dan Williams , Christian =?utf-8?B?S8O2bmln?= , Ira Weiny , John Hubbard , Don Dutile , Matthew Wilcox , Daniel Vetter Subject: Re: [RFC PATCH 14/15] PCI/P2PDMA: Introduce pci_mmap_p2pmem() Message-ID: <20201106172206.GS36674@ziepe.ca> References: <20201106170036.18713-1-logang@deltatee.com> <20201106170036.18713-15-logang@deltatee.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20201106170036.18713-15-logang@deltatee.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Fri, Nov 06, 2020 at 10:00:35AM -0700, Logan Gunthorpe wrote: > Introduce pci_mmap_p2pmem() which is a helper to allocate and mmap > a hunk of p2pmem into userspace. > > Signed-off-by: Logan Gunthorpe > drivers/pci/p2pdma.c | 104 +++++++++++++++++++++++++++++++++++++ > include/linux/pci-p2pdma.h | 6 +++ > 2 files changed, 110 insertions(+) > > diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c > index 9961e779f430..8eab53ac59ae 100644 > +++ b/drivers/pci/p2pdma.c > @@ -16,6 +16,7 @@ > #include > #include > #include > +#include > #include > #include > #include > @@ -1055,3 +1056,106 @@ ssize_t pci_p2pdma_enable_show(char *page, struct pci_dev *p2p_dev, > return sprintf(page, "%s\n", pci_name(p2p_dev)); > } > EXPORT_SYMBOL_GPL(pci_p2pdma_enable_show); > + > +struct pci_p2pdma_map { > + struct kref ref; > + struct pci_dev *pdev; > + void *kaddr; > + size_t len; > +}; Why have this at all? Nothing uses it and no vm_operations ops are implemented? This is very inflexable, it would be better if this is designed like io_remap_pfn where it just preps and fills the VMA, doesn't take ownership of the entire VMA Jason