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=-8.3 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI, SIGNED_OFF_BY,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_SANE_1 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 C7E61CA9ED0 for ; Fri, 1 Nov 2019 16:07:26 +0000 (UTC) Received: from bombadil.infradead.org (bombadil.infradead.org [198.137.202.133]) (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 99933222CB for ; Fri, 1 Nov 2019 16:07:26 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=lists.infradead.org header.i=@lists.infradead.org header.b="T9Q4qbo7" DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 99933222CB Authentication-Results: mail.kernel.org; dmarc=none (p=none dis=none) header.from=suse.cz Authentication-Results: mail.kernel.org; spf=none smtp.mailfrom=linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org DKIM-Signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=lists.infradead.org; s=bombadil.20170209; h=Sender: Content-Transfer-Encoding:Content-Type:Cc:List-Subscribe:List-Help:List-Post: List-Archive:List-Unsubscribe:List-Id:In-Reply-To:MIME-Version:References: Message-ID:Subject:To:From:Date:Reply-To:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: List-Owner; bh=oCMqrmWX1+CigECGWMRMPVl7SzsylHDSedu/SmqlJ4o=; b=T9Q4qbo76p/FeA AD82ZyCMAO+65oYh5FALLBrSR6GbgSbs7akTYwAiMgip5wgsjhw6Y2b/VN2kYuoKQWH4acPHN9P25 WjdhXaBwNWgImZUeB0rxLGzeY+pDgUAt0WJhsBnmCilD3jQGe5QSVHSKcj4WRE/+zP2BgQftpDpWf 8kF4EhcnjA1uYOP9RptO/8k583O07roWMSSkxVDlpU+nbQ6li6aNJBWD8KY47dutGfTv/OvHBe+6q owOsMI9+14+BiyKUa5fNTadtuI3IFDLPV1SsoICZfXaC8m+awnUGCSnmWGNFAMV5GWYCEmg1kW13m UiFvxrWr666M/98NGDWQ==; Received: from localhost ([127.0.0.1] helo=bombadil.infradead.org) by bombadil.infradead.org with esmtp (Exim 4.92.3 #3 (Red Hat Linux)) id 1iQZSP-0007QM-1Q; Fri, 01 Nov 2019 16:07:25 +0000 Received: from mx2.suse.de ([195.135.220.15] helo=mx1.suse.de) by bombadil.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1iQZSA-0006yL-UE for linux-mtd@lists.infradead.org; Fri, 01 Nov 2019 16:07:13 +0000 X-Virus-Scanned: by amavisd-new at test-mx.suse.de Received: from relay2.suse.de (unknown [195.135.220.254]) by mx1.suse.de (Postfix) with ESMTP id 5D4BDB4B9; Fri, 1 Nov 2019 16:07:07 +0000 (UTC) Received: by quack2.suse.cz (Postfix, from userid 1000) id F0F0D1E482F; Fri, 1 Nov 2019 17:07:06 +0100 (CET) Date: Fri, 1 Nov 2019 17:07:06 +0100 From: Jan Kara To: Sascha Hauer Subject: Re: [PATCH 04/10] quota: Allow to pass mount path to quotactl Message-ID: <20191101160706.GA23441@quack2.suse.cz> References: <20191030152702.14269-1-s.hauer@pengutronix.de> <20191030152702.14269-5-s.hauer@pengutronix.de> MIME-Version: 1.0 Content-Disposition: inline In-Reply-To: <20191030152702.14269-5-s.hauer@pengutronix.de> User-Agent: Mutt/1.10.1 (2018-07-13) X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20191101_090711_278177_68ECE082 X-CRM114-Status: GOOD ( 22.56 ) X-BeenThere: linux-mtd@lists.infradead.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: linux-fsdevel@vger.kernel.org, Richard Weinberger , linux-mtd@lists.infradead.org, kernel@pengutronix.de, Jan Kara Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "linux-mtd" Errors-To: linux-mtd-bounces+linux-mtd=archiver.kernel.org@lists.infradead.org On Wed 30-10-19 16:26:56, Sascha Hauer wrote: > This patch introduces the Q_PATH flag to the quotactl cmd argument. > When given, the path given in the special argument to quotactl will > be the mount path where the filesystem is mounted, instead of a path > to the block device. > This is necessary for filesystems which do not have a block device as > backing store. Particularly this is done for upcoming UBIFS support. > > Signed-off-by: Sascha Hauer Thanks for the patch! Some smaller comments below... > --- > fs/quota/quota.c | 37 ++++++++++++++++++++++++++++--------- > include/uapi/linux/quota.h | 1 + > 2 files changed, 29 insertions(+), 9 deletions(-) > > diff --git a/fs/quota/quota.c b/fs/quota/quota.c > index cb13fb76dbee..035cdd1b022b 100644 > --- a/fs/quota/quota.c > +++ b/fs/quota/quota.c > @@ -19,6 +19,7 @@ > #include > #include > #include > +#include > > static int check_quotactl_permission(struct super_block *sb, int type, int cmd, > qid_t id) > @@ -825,12 +826,16 @@ int kernel_quotactl(unsigned int cmd, const char __user *special, > { > uint cmds, type; > struct super_block *sb = NULL; > - struct path path, *pathp = NULL; > + struct path path, *pathp = NULL, qpath; Maybe call these two 'file_path', 'file_pathp', and 'sb_path' to make it clearer which path is which? > int ret; > + bool q_path; > > cmds = cmd >> SUBCMDSHIFT; > type = cmd & SUBCMDMASK; > > + q_path = cmds & Q_PATH; > + cmds &= ~Q_PATH; > + > /* > * As a special case Q_SYNC can be called without a specific device. > * It will iterate all superblocks that have quota enabled and call > @@ -855,19 +860,33 @@ int kernel_quotactl(unsigned int cmd, const char __user *special, > pathp = &path; > } > > - sb = quotactl_block(special, cmds); > - if (IS_ERR(sb)) { > - ret = PTR_ERR(sb); > - goto out; > + if (q_path) { > + ret = user_path_at(AT_FDCWD, special, LOOKUP_FOLLOW|LOOKUP_AUTOMOUNT, > + &qpath); > + if (ret) > + goto out1; > + > + sb = qpath.mnt->mnt_sb; > + } else { > + sb = quotactl_block(special, cmds); > + if (IS_ERR(sb)) { > + ret = PTR_ERR(sb); > + goto out; > + } > } > > ret = do_quotactl(sb, type, cmds, id, addr, pathp); > > - if (!quotactl_cmd_onoff(cmds)) > - drop_super(sb); > - else > - drop_super_exclusive(sb); > + if (!q_path) { > + if (!quotactl_cmd_onoff(cmds)) > + drop_super(sb); > + else > + drop_super_exclusive(sb); > + } > out: > + if (q_path) > + path_put(&qpath); > +out1: Why do you need out1? If you leave 'out' as is, things should just work. And you can also combine the above if like: if (q_path) { path_put(&qpath); } else { if (!quotactl_cmd_onoff(cmds)) drop_super(sb); else drop_super_exclusive(sb); } which would then make it more obvious, what's actually going on... Otherwise the patch looks good to me. Honza -- Jan Kara SUSE Labs, CR ______________________________________________________ Linux MTD discussion mailing list http://lists.infradead.org/mailman/listinfo/linux-mtd/