Return-Path: linux-nfs-owner@vger.kernel.org Received: from fieldses.org ([174.143.236.118]:43965 "EHLO fieldses.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753937Ab2IEU7V (ORCPT ); Wed, 5 Sep 2012 16:59:21 -0400 Date: Wed, 5 Sep 2012 16:59:20 -0400 To: "J. Bruce Fields" Cc: Al Viro , linux-nfs@vger.kernel.org, linux-fsdevel@vger.kernel.org, Jan Kara , Steven Whitehouse Subject: Re: [RFC PATCH 01/13] gfs2: Get rid of I_MUTEX_QUOTA usage Message-ID: <20120905205920.GA10724@fieldses.org> References: <1346878524-10585-1-git-send-email-bfields@redhat.com> <1346878524-10585-2-git-send-email-bfields@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <1346878524-10585-2-git-send-email-bfields@redhat.com> From: "J. Bruce Fields" Sender: linux-nfs-owner@vger.kernel.org List-ID: On Wed, Sep 05, 2012 at 04:55:11PM -0400, J. Bruce Fields wrote: > From: Jan Kara > > GFS2 uses i_mutex on its system quota inode to synchronize writes to > quota file. Since this is an internal inode to GFS2 (not part of directory > hiearchy or visible by user) we are safe to define locking rules for it. So > let's just get it its own locking class to make it clear. By the way, Steve, is there any reason you haven't taken this through the gfs2 tree? --b. > > CC: Steven Whitehouse > Signed-off-by: Jan Kara > Signed-off-by: J. Bruce Fields > --- > fs/gfs2/ops_fstype.c | 8 ++++++++ > fs/gfs2/quota.c | 2 +- > 2 files changed, 9 insertions(+), 1 deletion(-) > > diff --git a/fs/gfs2/ops_fstype.c b/fs/gfs2/ops_fstype.c > index e5af9dc..e443966 100644 > --- a/fs/gfs2/ops_fstype.c > +++ b/fs/gfs2/ops_fstype.c > @@ -19,6 +19,7 @@ > #include > #include > #include > +#include > > #include "gfs2.h" > #include "incore.h" > @@ -766,6 +767,7 @@ fail: > return error; > } > > +static struct lock_class_key gfs2_quota_imutex_key; > > static int init_inodes(struct gfs2_sbd *sdp, int undo) > { > @@ -803,6 +805,12 @@ static int init_inodes(struct gfs2_sbd *sdp, int undo) > fs_err(sdp, "can't get quota file inode: %d\n", error); > goto fail_rindex; > } > + /* > + * i_mutex on quota files is special. Since this inode is hidden system > + * file, we are safe to define locking ourselves. > + */ > + lockdep_set_class(&sdp->sd_quota_inode->i_mutex, > + &gfs2_quota_imutex_key); > > error = gfs2_rindex_update(sdp); > if (error) > diff --git a/fs/gfs2/quota.c b/fs/gfs2/quota.c > index a3bde91..3d9c989 100644 > --- a/fs/gfs2/quota.c > +++ b/fs/gfs2/quota.c > @@ -781,7 +781,7 @@ static int do_sync(unsigned int num_qd, struct gfs2_quota_data **qda) > return -ENOMEM; > > sort(qda, num_qd, sizeof(struct gfs2_quota_data *), sort_qd, NULL); > - mutex_lock_nested(&ip->i_inode.i_mutex, I_MUTEX_QUOTA); > + mutex_lock(&ip->i_inode.i_mutex); > for (qx = 0; qx < num_qd; qx++) { > error = gfs2_glock_nq_init(qda[qx]->qd_gl, LM_ST_EXCLUSIVE, > GL_NOCACHE, &ghs[qx]); > -- > 1.7.9.5 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-nfs" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html