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=-18.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER, INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,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 E2FF8C433ED for ; Thu, 22 Apr 2021 15:10:23 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id B478A6143B for ; Thu, 22 Apr 2021 15:10:23 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S237679AbhDVPK4 (ORCPT ); Thu, 22 Apr 2021 11:10:56 -0400 Received: from mx2.suse.de ([195.135.220.15]:52052 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S236586AbhDVPKr (ORCPT ); Thu, 22 Apr 2021 11:10:47 -0400 X-Virus-Scanned: by amavisd-new at test-mx.suse.de DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.com; s=susede1; t=1619104211; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=gTxz0RbWnUOZh4apGxwrsu84odP0er4fykNXzBAMpag=; b=OX0bucQn5aKzgc3RTioNoOR5BErPdayoju9pA5S5pCYLyODdOwrADpSziKmUf+9lpeLHq/ 9Mf3LUt3Pz6e3HoQaDoc3vmW9oI3MwNlLswg5N8qCQBao4KAVZC3OEBWO7GVTKg5IwH9Ia GF/vmkAWug36+NLP+GZgc6yX11cDe8o= Received: from relay2.suse.de (unknown [195.135.221.27]) by mx2.suse.de (Postfix) with ESMTP id 63C6EB174; Thu, 22 Apr 2021 15:10:11 +0000 (UTC) From: Juergen Gross To: xen-devel@lists.xenproject.org, linux-kernel@vger.kernel.org Cc: Juergen Gross , Boris Ostrovsky , Stefano Stabellini , Peter Zijlstra Subject: [PATCH 3/3] xen: assume XENFEAT_gnttab_map_avail_bits being set for pv guests Date: Thu, 22 Apr 2021 17:10:07 +0200 Message-Id: <20210422151007.2205-4-jgross@suse.com> X-Mailer: git-send-email 2.26.2 In-Reply-To: <20210422151007.2205-1-jgross@suse.com> References: <20210422151007.2205-1-jgross@suse.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org XENFEAT_gnttab_map_avail_bits is always set in Xen 4.0 and newer. Remove coding assuming it might be zero. Signed-off-by: Juergen Gross --- drivers/xen/gntdev.c | 36 ++---------------------------------- 1 file changed, 2 insertions(+), 34 deletions(-) diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index f01d58c7a042..93818816e137 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -266,20 +266,13 @@ static int find_grant_ptes(pte_t *pte, unsigned long addr, void *data) { struct gntdev_grant_map *map = data; unsigned int pgnr = (addr - map->vma->vm_start) >> PAGE_SHIFT; - int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte; + int flags = map->flags | GNTMAP_application_map | GNTMAP_contains_pte | + (1 << _GNTMAP_guest_avail0); u64 pte_maddr; BUG_ON(pgnr >= map->count); pte_maddr = arbitrary_virt_to_machine(pte).maddr; - /* - * Set the PTE as special to force get_user_pages_fast() fall - * back to the slow path. If this is not supported as part of - * the grant map, it will be done afterwards. - */ - if (xen_feature(XENFEAT_gnttab_map_avail_bits)) - flags |= (1 << _GNTMAP_guest_avail0); - gnttab_set_map_op(&map->map_ops[pgnr], pte_maddr, flags, map->grants[pgnr].ref, map->grants[pgnr].domid); @@ -288,14 +281,6 @@ static int find_grant_ptes(pte_t *pte, unsigned long addr, void *data) return 0; } -#ifdef CONFIG_X86 -static int set_grant_ptes_as_special(pte_t *pte, unsigned long addr, void *data) -{ - set_pte_at(current->mm, addr, pte, pte_mkspecial(*pte)); - return 0; -} -#endif - int gntdev_map_grant_pages(struct gntdev_grant_map *map) { int i, err = 0; @@ -1053,23 +1038,6 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) err = vm_map_pages_zero(vma, map->pages, map->count); if (err) goto out_put_map; - } else { -#ifdef CONFIG_X86 - /* - * If the PTEs were not made special by the grant map - * hypercall, do so here. - * - * This is racy since the mapping is already visible - * to userspace but userspace should be well-behaved - * enough to not touch it until the mmap() call - * returns. - */ - if (!xen_feature(XENFEAT_gnttab_map_avail_bits)) { - apply_to_page_range(vma->vm_mm, vma->vm_start, - vma->vm_end - vma->vm_start, - set_grant_ptes_as_special, NULL); - } -#endif } return 0; -- 2.26.2