From: "Serge E. Hallyn" Subject: Re: [PATCH 5/5] NFS: Correct the NFS mount path when following a referral Date: Tue, 23 Jun 2009 15:42:02 -0500 Message-ID: <20090623204202.GA25969@us.ibm.com> References: <20090622190913.27923.31665.stgit@heimdal.trondhjem.org> <20090622190914.27923.84173.stgit@heimdal.trondhjem.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: Linus Torvalds , Al Viro , Christoph Hellwig , linux-fsdevel@vger.kernel.org, linux-nfs@vger.kernel.org, linux-kernel@vger.kernel.org To: Trond Myklebust Return-path: Received: from e31.co.us.ibm.com ([32.97.110.149]:57043 "EHLO e31.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752228AbZFWUl5 (ORCPT ); Tue, 23 Jun 2009 16:41:57 -0400 In-Reply-To: <20090622190914.27923.84173.stgit-rJ7iovZKK19ZJLDQqaL3InhyD016LWXt@public.gmane.org> Sender: linux-nfs-owner@vger.kernel.org List-ID: Quoting Trond Myklebust (Trond.Myklebust@netapp.com): > Signed-off-by: Trond Myklebust > --- > > fs/nfs/super.c | 24 ++++++++++++++++++++++++ > 1 files changed, 24 insertions(+), 0 deletions(-) > > > diff --git a/fs/nfs/super.c b/fs/nfs/super.c > index 8da7e59..daecbad 100644 > --- a/fs/nfs/super.c > +++ b/fs/nfs/super.c > @@ -2548,6 +2548,27 @@ static struct vfsmount *nfs_do_root_mount(struct file_system_type *fs_type, > return root_mnt; > } > > +static void nfs_fix_devname(const struct path *path, struct vfsmount *mnt) > +{ > + char *page = (char *) __get_free_page(GFP_KERNEL); > + char *devname, *tmp; > + > + if (page == NULL) > + return; > + devname = nfs_path(path->mnt->mnt_devname, > + path->mnt->mnt_root, path->dentry, > + page, PAGE_SIZE); > + if (devname == NULL) > + goto out_freepage; > + tmp = kstrdup(devname, GFP_KERNEL); > + if (tmp == NULL) > + goto out_freepage; > + kfree(mnt->mnt_devname); > + mnt->mnt_devname = tmp; (looking through patch 3 a bit) is this expected to be safe because all callers will send in a mnt which was privately mounted as nfs root_mnt through vfs_kern_mount? So that at this point noone else can have a ref to mnt? If that isn't the intent, then this seems problematic... (If it is, it seems worth commenting both so that every reader doesn't feel compelled to verify, and so that no new callers will naively violate that expectation) thanks, -serge > +out_freepage: > + free_page((unsigned long)page); > +} > + > static int nfs_follow_remote_path(struct vfsmount *root_mnt, > const char *export_path, struct vfsmount *mnt_target) > { > @@ -2574,6 +2595,9 @@ static int nfs_follow_remote_path(struct vfsmount *root_mnt, > mnt_target->mnt_sb = s; > mnt_target->mnt_root = dget(nd.path.dentry); > > + /* Correct the device pathname */ > + nfs_fix_devname(&nd.path, mnt_target); > + > path_put(&nd.path); > down_write(&s->s_umount); > return 0; > > -- > 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