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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 0C019EB64DA for ; Tue, 18 Jul 2023 09:54:48 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S232032AbjGRJyp (ORCPT ); Tue, 18 Jul 2023 05:54:45 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48864 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231696AbjGRJyJ (ORCPT ); Tue, 18 Jul 2023 05:54:09 -0400 Received: from kylie.crudebyte.com (kylie.crudebyte.com [5.189.157.229]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 41AB21FC6 for ; Tue, 18 Jul 2023 02:53:11 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=crudebyte.com; s=kylie; h=Content-Type:Content-Transfer-Encoding: MIME-Version:References:In-Reply-To:Message-ID:Date:Subject:Cc:To:From: Content-ID:Content-Description; bh=bLG3Hj/avYD20zcuWTTF4BBDPz5pcBq1H1Srh8DnyRo=; b=mEBUDxLV+mRH37IuwGieU9tBF4 0iY8NsX3ZO46Y5PkkAyXDmb+cqHOBqKst3QCtnqQWQ80nL1mY/xDsoMXyUvw5NxZ0nXCcABuN+snO 7lVhAo/3/n7+6Xy3wlRg4yfgtWYb0zD2Oo5mEJwiJO69QrPbpIfU303kk6KdfhNfAMmhHRiRccd/r d81vULpFHnJE15VXRpYDZfCKAVhjlm8QdZaqbHO32gQujQwG+ycl4SL9SkKcsVkOTP9H+HcUIWce0 wCIZGjRG+FQe63p6wJnUizVhTgMRyfBZbMr5AZLb/2LagIlPocmVBhNrF8TNn44pN0Lx8n6T0twfh NirXob45bTD8keIjQcphffHHfjGTZSr1ZN09IXQvo+13dNkKHDSUP1IHLSJVHWDzK1iNOW78tTurM I10aLNSHD5MQSGDbosTwh6cH3Ez/oNWbV7e7XOQN3VoD5kkCL9Es8YrQtwjo4vIJnP874Y1LSIxij /rDWD+ZGgx1pt3XaZbSiTg623k21l9wNsi5KG5KZ3p5RfMaqox+zEdEqF12TPOU5Anqx6vPQaea+x UnyJbY/sov7gSCJgPXdoxRPBKOLuOFsT0Me86w+rD335H2GkNCD1NqiDzBzyz9R/KsOWkk/8bmVok Uu15YGzJWLMXu/kK9iuxtTO3kTfKi6XoK6VRKssa4=; From: Christian Schoenebeck To: Eric Van Hensbergen , Dominique Martinet Cc: Latchesar Ionkov , v9fs@lists.linux.dev, linux-kernel@vger.kernel.org, kernel@pengutronix.de, Robert Schwebel Subject: Re: [PATCH 1/3] fs/9p: remove unecessary and overrestrictive check Date: Tue, 18 Jul 2023 11:17:16 +0200 Message-ID: <9085752.7RgNvelpzP@silver> In-Reply-To: References: <20230716-fixes-overly-restrictive-mmap-v1-0-0683b283b932@kernel.org> <20230716-fixes-overly-restrictive-mmap-v1-1-0683b283b932@kernel.org> MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tuesday, July 18, 2023 4:45:25 AM CEST Dominique Martinet wrote: > Eric Van Hensbergen wrote on Mon, Jul 17, 2023 at 04:29:00PM +0000: > > This eliminates a check for shared that was overrestrictive and > > duplicated a check in generic_file_readonly_mmap. > > generic_file_readonly_mmap checks for VM_SHARED + VM_MAYWRITE, > so it isn't exactly "duplicating" the check.. But I agree we don't need > it; we used to have the mmap op be generic_file_readonly_mmap directly > previously. It should be removed from the commit log then though. > I'd argue we don't need to invalidate inode pages either if there is no > writeback cache, there shouldn't be anything in it? but that can be done > separately, and extra invalidation won't bring harm anyway. Unnecessary performance penalty? So I would drop that in a separate patch. > Reviewed-by: Dominique Martinet Feel free to add my RB as well: Reviewed-by: Christian Schoenebeck > > > > Signed-off-by: Eric Van Hensbergen > > --- > > fs/9p/vfs_file.c | 2 -- > > 1 file changed, 2 deletions(-) > > > > diff --git a/fs/9p/vfs_file.c b/fs/9p/vfs_file.c > > index 2996fb00387fa..bda3abd6646b8 100644 > > --- a/fs/9p/vfs_file.c > > +++ b/fs/9p/vfs_file.c > > @@ -506,8 +506,6 @@ v9fs_file_mmap(struct file *filp, struct vm_area_struct *vma) > > > > if (!(v9ses->cache & CACHE_WRITEBACK)) { > > p9_debug(P9_DEBUG_CACHE, "(no mmap mode)"); > > - if (vma->vm_flags & VM_MAYSHARE) > > - return -ENODEV; > > invalidate_inode_pages2(filp->f_mapping); > > return generic_file_readonly_mmap(filp, vma); > > } > > > >