Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1947081AbbEBTeu (ORCPT ); Sat, 2 May 2015 15:34:50 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:45830 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1946209AbbEBTeq (ORCPT ); Sat, 2 May 2015 15:34:46 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, "Eric W. Biederman" Subject: [PATCH 3.19 093/177] mnt: Improve the umount_tree flags Date: Sat, 2 May 2015 21:01:55 +0200 Message-Id: <20150502190123.653551148@linuxfoundation.org> X-Mailer: git-send-email 2.3.7 In-Reply-To: <20150502190119.666291882@linuxfoundation.org> References: <20150502190119.666291882@linuxfoundation.org> User-Agent: quilt/0.64 MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-15 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5028 Lines: 162 3.19-stable review patch. If anyone has any objections, please let me know. ------------------ From: "Eric W. Biederman" commit e819f152104c9f7c9fe50e1aecce6f5d4bf06d65 upstream. - Remove the unneeded declaration from pnode.h - Mark umount_tree static as it has no callers outside of namespace.c - Define an enumeration of umount_tree's flags. - Pass umount_tree's flags in by name This removes the magic numbers 0, 1 and 2 making the code a little clearer and makes it possible for there to be lazy unmounts that don't propagate. Which is what __detach_mounts actually wants for example. Signed-off-by: "Eric W. Biederman" Signed-off-by: Greg Kroah-Hartman --- fs/namespace.c | 31 ++++++++++++++++--------------- fs/pnode.h | 1 - 2 files changed, 16 insertions(+), 16 deletions(-) --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1323,14 +1323,15 @@ static inline void namespace_lock(void) down_write(&namespace_sem); } +enum umount_tree_flags { + UMOUNT_SYNC = 1, + UMOUNT_PROPAGATE = 2, +}; /* * mount_lock must be held * namespace_sem must be held for write - * how = 0 => just this tree, don't propagate - * how = 1 => propagate; we know that nobody else has reference to any victims - * how = 2 => lazy umount */ -void umount_tree(struct mount *mnt, int how) +static void umount_tree(struct mount *mnt, enum umount_tree_flags how) { HLIST_HEAD(tmp_list); struct mount *p; @@ -1344,7 +1345,7 @@ void umount_tree(struct mount *mnt, int hlist_for_each_entry(p, &tmp_list, mnt_hash) list_del_init(&p->mnt_child); - if (how) + if (how & UMOUNT_PROPAGATE) propagate_umount(&tmp_list); hlist_for_each_entry(p, &tmp_list, mnt_hash) { @@ -1352,7 +1353,7 @@ void umount_tree(struct mount *mnt, int list_del_init(&p->mnt_list); __touch_mnt_namespace(p->mnt_ns); p->mnt_ns = NULL; - if (how < 2) + if (how & UMOUNT_SYNC) p->mnt.mnt_flags |= MNT_SYNC_UMOUNT; if (mnt_has_parent(p)) { hlist_del_init(&p->mnt_mp_list); @@ -1457,14 +1458,14 @@ static int do_umount(struct mount *mnt, if (flags & MNT_DETACH) { if (!list_empty(&mnt->mnt_list)) - umount_tree(mnt, 2); + umount_tree(mnt, UMOUNT_PROPAGATE); retval = 0; } else { shrink_submounts(mnt); retval = -EBUSY; if (!propagate_mount_busy(mnt, 2)) { if (!list_empty(&mnt->mnt_list)) - umount_tree(mnt, 1); + umount_tree(mnt, UMOUNT_PROPAGATE|UMOUNT_SYNC); retval = 0; } } @@ -1496,7 +1497,7 @@ void __detach_mounts(struct dentry *dent lock_mount_hash(); while (!hlist_empty(&mp->m_list)) { mnt = hlist_entry(mp->m_list.first, struct mount, mnt_mp_list); - umount_tree(mnt, 2); + umount_tree(mnt, UMOUNT_PROPAGATE); } unlock_mount_hash(); put_mountpoint(mp); @@ -1658,7 +1659,7 @@ struct mount *copy_tree(struct mount *mn out: if (res) { lock_mount_hash(); - umount_tree(res, 0); + umount_tree(res, UMOUNT_SYNC); unlock_mount_hash(); } return q; @@ -1682,7 +1683,7 @@ void drop_collected_mounts(struct vfsmou { namespace_lock(); lock_mount_hash(); - umount_tree(real_mount(mnt), 0); + umount_tree(real_mount(mnt), UMOUNT_SYNC); unlock_mount_hash(); namespace_unlock(); } @@ -1865,7 +1866,7 @@ static int attach_recursive_mnt(struct m out_cleanup_ids: while (!hlist_empty(&tree_list)) { child = hlist_entry(tree_list.first, struct mount, mnt_hash); - umount_tree(child, 0); + umount_tree(child, UMOUNT_SYNC); } unlock_mount_hash(); cleanup_group_ids(source_mnt, NULL); @@ -2045,7 +2046,7 @@ static int do_loopback(struct path *path err = graft_tree(mnt, parent, mp); if (err) { lock_mount_hash(); - umount_tree(mnt, 0); + umount_tree(mnt, UMOUNT_SYNC); unlock_mount_hash(); } out2: @@ -2416,7 +2417,7 @@ void mark_mounts_for_expiry(struct list_ while (!list_empty(&graveyard)) { mnt = list_first_entry(&graveyard, struct mount, mnt_expire); touch_mnt_namespace(mnt->mnt_ns); - umount_tree(mnt, 1); + umount_tree(mnt, UMOUNT_PROPAGATE|UMOUNT_SYNC); } unlock_mount_hash(); namespace_unlock(); @@ -2487,7 +2488,7 @@ static void shrink_submounts(struct moun m = list_first_entry(&graveyard, struct mount, mnt_expire); touch_mnt_namespace(m->mnt_ns); - umount_tree(m, 1); + umount_tree(m, UMOUNT_PROPAGATE|UMOUNT_SYNC); } } } --- a/fs/pnode.h +++ b/fs/pnode.h @@ -47,7 +47,6 @@ int get_dominating_id(struct mount *mnt, unsigned int mnt_get_count(struct mount *mnt); void mnt_set_mountpoint(struct mount *, struct mountpoint *, struct mount *); -void umount_tree(struct mount *, int); struct mount *copy_tree(struct mount *, struct dentry *, int); bool is_path_reachable(struct mount *, struct dentry *, const struct path *root); -- 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/