From patchwork Thu Jun 3 23:59:55 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Kasireddy, Vivek" X-Patchwork-Id: 12298447 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=-16.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham 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 5AEE3C47082 for ; Fri, 4 Jun 2021 00:14:06 +0000 (UTC) Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 055286140A for ; Fri, 4 Jun 2021 00:14:05 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 055286140A Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=dri-devel-bounces@lists.freedesktop.org Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 5EA776F545; Fri, 4 Jun 2021 00:14:05 +0000 (UTC) Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by gabe.freedesktop.org (Postfix) with ESMTPS id 8116C6F545 for ; Fri, 4 Jun 2021 00:14:03 +0000 (UTC) IronPort-SDR: t0NA/KEf1FcsT1Uh9V+Kwl+SC2NuLJB/sITYoqXE1xiVwKcF2f1m566OmOCukRaWJd8mEYi+9X vUffsrsyZnrg== X-IronPort-AV: E=McAfee;i="6200,9189,10004"; a="204168241" X-IronPort-AV: E=Sophos;i="5.83,246,1616482800"; d="scan'208";a="204168241" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Jun 2021 17:13:04 -0700 IronPort-SDR: YESAeTwZFxhuREo9C0b3gXJ7h+IlcD5EopVlvsw4TgBN8JzLIqTSGRdxCGneNjlurqmNOYjhjK xJMzoXLyMFCg== X-IronPort-AV: E=Sophos;i="5.83,246,1616482800"; d="scan'208";a="400761672" Received: from vkasired-desk2.fm.intel.com ([10.105.128.127]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 03 Jun 2021 17:13:03 -0700 From: Vivek Kasireddy To: dri-devel@lists.freedesktop.org Subject: [PATCH] udmabuf: Add support for mapping hugepages (v2) Date: Thu, 3 Jun 2021 16:59:55 -0700 Message-Id: <20210603235955.341043-1-vivek.kasireddy@intel.com> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20210603094424.p6hx7dx42nkmzoqz@sirius.home.kraxel.org> References: <20210603094424.p6hx7dx42nkmzoqz@sirius.home.kraxel.org> MIME-Version: 1.0 X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Vivek Kasireddy , Gerd Hoffmann Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" If the VMM's (Qemu) memory backend is backed up by memfd + Hugepages (hugetlbfs and not THP), we have to first find the hugepage(s) where the Guest allocations are located and then extract the regular 4k sized subpages from them. v2: Ensure that the subpage offsets are calculated correctly when the range of subpage allocations cuts across multiple hugepages. Cc: Gerd Hoffmann Signed-off-by: Vivek Kasireddy --- drivers/dma-buf/udmabuf.c | 46 ++++++++++++++++++++++++++++++++------- 1 file changed, 38 insertions(+), 8 deletions(-) diff --git a/drivers/dma-buf/udmabuf.c b/drivers/dma-buf/udmabuf.c index db732f71e59a..f053d12a1eb3 100644 --- a/drivers/dma-buf/udmabuf.c +++ b/drivers/dma-buf/udmabuf.c @@ -11,6 +11,7 @@ #include #include #include +#include static const u32 list_limit = 1024; /* udmabuf_create_list->count limit */ static const size_t size_limit_mb = 64; /* total dmabuf size, in megabytes */ @@ -162,8 +163,10 @@ static long udmabuf_create(struct miscdevice *device, struct file *memfd = NULL; struct udmabuf *ubuf; struct dma_buf *buf; - pgoff_t pgoff, pgcnt, pgidx, pgbuf = 0, pglimit; - struct page *page; + pgoff_t pgoff, pgcnt, pgidx, pgbuf = 0, pglimit, subpgoff; + uint32_t maxsubpgs; + struct page *page, *hpage = NULL; + struct hstate *hpstate; int seals, ret = -EINVAL; u32 i, flags; @@ -194,7 +197,8 @@ static long udmabuf_create(struct miscdevice *device, memfd = fget(list[i].memfd); if (!memfd) goto err; - if (!shmem_mapping(file_inode(memfd)->i_mapping)) + if (!shmem_mapping(file_inode(memfd)->i_mapping) && + !is_file_hugepages(memfd)) goto err; seals = memfd_fcntl(memfd, F_GET_SEALS, 0); if (seals == -EINVAL) @@ -205,12 +209,38 @@ static long udmabuf_create(struct miscdevice *device, goto err; pgoff = list[i].offset >> PAGE_SHIFT; pgcnt = list[i].size >> PAGE_SHIFT; + if (is_file_hugepages(memfd)) { + hpstate = hstate_file(memfd); + pgoff = list[i].offset >> huge_page_shift(hpstate); + subpgoff = (list[i].offset & + ~huge_page_mask(hpstate)) >> PAGE_SHIFT; + maxsubpgs = huge_page_size(hpstate) >> PAGE_SHIFT; + } for (pgidx = 0; pgidx < pgcnt; pgidx++) { - page = shmem_read_mapping_page( - file_inode(memfd)->i_mapping, pgoff + pgidx); - if (IS_ERR(page)) { - ret = PTR_ERR(page); - goto err; + if (is_file_hugepages(memfd)) { + hpage = find_get_page_flags( + file_inode(memfd)->i_mapping, + pgoff, FGP_ACCESSED); + if (IS_ERR(hpage)) { + ret = PTR_ERR(hpage); + goto err; + } + + page = hpage + (subpgoff % maxsubpgs); + get_page(page); + put_page(hpage); + + subpgoff++; + if (subpgoff % maxsubpgs == 0) + pgoff++; + } else { + page = shmem_read_mapping_page( + file_inode(memfd)->i_mapping, + pgoff + pgidx); + if (IS_ERR(page)) { + ret = PTR_ERR(page); + goto err; + } } ubuf->pages[pgbuf++] = page; }