Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753111AbZLAEMM (ORCPT ); Mon, 30 Nov 2009 23:12:12 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752274AbZLAEMK (ORCPT ); Mon, 30 Nov 2009 23:12:10 -0500 Received: from filer.fsl.cs.sunysb.edu ([130.245.126.2]:50742 "EHLO filer.fsl.cs.sunysb.edu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750828AbZLAEMJ (ORCPT ); Mon, 30 Nov 2009 23:12:09 -0500 Date: Mon, 30 Nov 2009 23:11:43 -0500 Message-Id: <200912010411.nB14Bhvw030326@agora.fsl.cs.sunysb.edu> From: Erez Zadok To: Valerie Aurora Cc: Jan Blunck , Alexander Viro , Christoph Hellwig , Andy Whitcroft , Scott James Remnant , Sandu Popa Marius , Jan Rekorajski , "J. R. Okajima" , Arnd Bergmann , Vladimir Dronnikov , Felix Fietkau , linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 26/41] union-mount: stop lookup when finding a whiteout In-reply-to: Your message of "Wed, 21 Oct 2009 12:19:24 PDT." <1256152779-10054-27-git-send-email-vaurora@redhat.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 4528 Lines: 142 In message <1256152779-10054-27-git-send-email-vaurora@redhat.com>, Valerie Aurora writes: > From: Jan Blunck > > Stop the lookup if we find a whiteout during union path lookup. Was it intentional to have a separate patch which adds opaque directories support, or should it be part of the larger patch #24? > Signed-off-by: Jan Blunck > Signed-off-by: Valerie Aurora > --- > fs/namei.c | 30 ++++++++++++++++++++++-------- > 1 files changed, 22 insertions(+), 8 deletions(-) > > diff --git a/fs/namei.c b/fs/namei.c > index 8ebbf4f..fb463ac 100644 > --- a/fs/namei.c > +++ b/fs/namei.c > @@ -442,10 +442,10 @@ static int __cache_lookup_topmost(struct nameidata *nd, struct qstr *name, > path->dentry = dentry; > path->mnt = dentry ? nd->path.mnt : NULL; > > - if (!dentry || dentry->d_inode) > + if (!dentry || (dentry->d_inode || d_is_whiteout(dentry))) > return !dentry; Unnecessary set of () around second and third || clauses above. > > - /* look for the first non-negative dentry */ > + /* look for the first non-negative or whiteout dentry */ > > while (follow_union_down(&nd->path.mnt, &nd->path.dentry)) { > dentry = d_hash_and_lookup(nd->path.dentry, name); > @@ -467,7 +467,7 @@ static int __cache_lookup_topmost(struct nameidata *nd, struct qstr *name, > goto out_dput; > } > > - if (dentry->d_inode) > + if (dentry->d_inode || d_is_whiteout(dentry)) > goto out_dput; > > dput(dentry); > @@ -505,6 +505,11 @@ static int __cache_lookup_build_union(struct nameidata *nd, struct qstr *name, > return 1; > } > > + if (d_is_whiteout(dentry)) { > + dput(dentry); > + break; > + } > + > if (!dentry->d_inode) { > dput(dentry); > continue; > @@ -716,7 +721,6 @@ out_unlock: > * type mismatch and whiteouts. > * > * FIXME: > - * - handle DT_WHT Ah, ok: so this patch adds DT_WHT support. Still, I don't see why it can't just be folded into the already pretty large patch #24; and maybe patch 24 could be split a different way to facilitated easier reviewing? > * - handle union stacks in use > * - handle union stacks mounted upon union stacks > * - avoid unnecessary allocations of union locks > @@ -731,7 +735,7 @@ static int __real_lookup_topmost(struct nameidata *nd, struct qstr *name, > if (err) > return err; > > - if (path->dentry->d_inode) > + if (path->dentry->d_inode || d_is_whiteout(path->dentry)) > return 0; > > while (follow_union_down(&nd->path.mnt, &nd->path.dentry)) { > @@ -747,7 +751,7 @@ static int __real_lookup_topmost(struct nameidata *nd, struct qstr *name, > if (err) > goto out; > > - if (next.dentry->d_inode) { > + if (next.dentry->d_inode || d_is_whiteout(next.dentry)) { > dput(path->dentry); > mntget(next.mnt); > *path = next; > @@ -790,6 +794,11 @@ static int __real_lookup_build_union(struct nameidata *nd, struct qstr *name, > if (err) > goto out; > > + if (d_is_whiteout(next.dentry)) { > + dput(next.dentry); > + break; > + } > + > if (!next.dentry->d_inode) { > dput(next.dentry); > continue; > @@ -1610,7 +1619,7 @@ static int __hash_lookup_topmost(struct nameidata *nd, struct qstr *name, > if (err) > return err; > > - if (path->dentry->d_inode) > + if (path->dentry->d_inode || d_is_whiteout(path->dentry)) > return 0; > > while (follow_union_down(&nd->path.mnt, &nd->path.dentry)) { > @@ -1628,7 +1637,7 @@ static int __hash_lookup_topmost(struct nameidata *nd, struct qstr *name, > if (err) > goto out; > > - if (next.dentry->d_inode) { > + if (next.dentry->d_inode || d_is_whiteout(next.dentry)) { > dput(path->dentry); > mntget(next.mnt); > *path = next; > @@ -1666,6 +1675,11 @@ static int __hash_lookup_build_union(struct nameidata *nd, struct qstr *name, > if (err) > goto out; > > + if (d_is_whiteout(next.dentry)) { > + dput(next.dentry); > + break; > + } > + > if (!next.dentry->d_inode) { > dput(next.dentry); > continue; > -- > 1.6.3.3 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Erez. -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/