From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: [RFC][PATCH 1/3] vfs: Keep a list of mounts on a mount point Date: Fri, 04 Oct 2013 15:42:37 -0700 Message-ID: <87fvsg1wv6.fsf_-_@xmission.com> References: <87a9kkax0j.fsf@xmission.com> <8761v7h2pt.fsf@tw-ebiederman.twitter.com> <87li281wx6.fsf_-_@xmission.com> Mime-Version: 1.0 Content-Type: text/plain Cc: "Serge E. Hallyn" , Al Viro , Linux-Fsdevel , Kernel Mailing List , Andy Lutomirski , Rob Landley , Linus Torvalds To: Miklos Szeredi Return-path: In-Reply-To: <87li281wx6.fsf_-_@xmission.com> (Eric W. Biederman's message of "Fri, 04 Oct 2013 15:41:25 -0700") Sender: linux-kernel-owner@vger.kernel.org List-Id: linux-fsdevel.vger.kernel.org Signed-off-by: Eric W. Biederman --- fs/mount.h | 2 ++ fs/namespace.c | 5 +++++ 2 files changed, 7 insertions(+), 0 deletions(-) diff --git a/fs/mount.h b/fs/mount.h index 64a858143ff9..e4342b8dfab1 100644 --- a/fs/mount.h +++ b/fs/mount.h @@ -21,6 +21,7 @@ struct mnt_pcp { struct mountpoint { struct list_head m_hash; struct dentry *m_dentry; + struct list_head m_list; int m_count; }; @@ -47,6 +48,7 @@ struct mount { struct mount *mnt_master; /* slave is on master->mnt_slave_list */ struct mnt_namespace *mnt_ns; /* containing namespace */ struct mountpoint *mnt_mp; /* where is it mounted */ + struct list_head mnt_mp_list; /* list mounts with the same mountpoint */ #ifdef CONFIG_FSNOTIFY struct hlist_head mnt_fsnotify_marks; __u32 mnt_fsnotify_mask; diff --git a/fs/namespace.c b/fs/namespace.c index da5c49483430..d092964fe7f9 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -197,6 +197,7 @@ static struct mount *alloc_vfsmnt(const char *name) INIT_LIST_HEAD(&mnt->mnt_share); INIT_LIST_HEAD(&mnt->mnt_slave_list); INIT_LIST_HEAD(&mnt->mnt_slave); + INIT_LIST_HEAD(&mnt->mnt_mp_list); #ifdef CONFIG_FSNOTIFY INIT_HLIST_HEAD(&mnt->mnt_fsnotify_marks); #endif @@ -636,6 +637,7 @@ static struct mountpoint *new_mountpoint(struct dentry *dentry) mp->m_dentry = dentry; mp->m_count = 1; list_add(&mp->m_hash, chain); + INIT_LIST_HEAD(&mp->m_list); return mp; } @@ -691,6 +693,7 @@ static void detach_mnt(struct mount *mnt, struct path *old_path) list_del_init(&mnt->mnt_hash); put_mountpoint(mnt->mnt_mp); mnt->mnt_mp = NULL; + list_del_init(&mnt->mnt_mp_list); } /* @@ -705,6 +708,7 @@ void mnt_set_mountpoint(struct mount *mnt, child_mnt->mnt_mountpoint = dget(mp->m_dentry); child_mnt->mnt_parent = mnt; child_mnt->mnt_mp = mp; + list_add_tail(&child_mnt->mnt_mp_list, &mp->m_list); } /* @@ -1193,6 +1197,7 @@ void umount_tree(struct mount *mnt, int propagate) p->mnt_parent->mnt_ghosts++; put_mountpoint(p->mnt_mp); p->mnt_mp = NULL; + list_del_init(&mnt->mnt_mp_list); } change_mnt_propagation(p, MS_PRIVATE); } -- 1.7.5.4