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| author | Al Viro <viro@zeniv.linux.org.uk> | 2011-11-23 19:26:23 -0500 |
|---|---|---|
| committer | Al Viro <viro@zeniv.linux.org.uk> | 2012-01-03 22:52:36 -0500 |
| commit | b2dba1af3c4157040303a76d25216b1713d333d0 (patch) | |
| tree | c846b1c8074d29b9fc02ef3eeda98631dfd6ee94 /fs/namespace.c | |
| parent | aa9c0e07bb90589186f3b5a0ca97660c2cb50806 (diff) | |
| download | linux-3.10-b2dba1af3c4157040303a76d25216b1713d333d0.tar.gz linux-3.10-b2dba1af3c4157040303a76d25216b1713d333d0.tar.bz2 linux-3.10-b2dba1af3c4157040303a76d25216b1713d333d0.zip | |
vfs: new internal helper: mnt_has_parent(mnt)
vfsmounts have ->mnt_parent pointing either to a different vfsmount
or to itself; it's never NULL and termination condition in loops
traversing the tree towards root is mnt == mnt->mnt_parent. At least
one place (see the next patch) is confused about what's going on;
let's add an explicit helper checking it right way and use it in
all places where we need it. Not that there had been too many,
but...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Diffstat (limited to 'fs/namespace.c')
| -rw-r--r-- | fs/namespace.c | 14 |
1 files changed, 7 insertions, 7 deletions
diff --git a/fs/namespace.c b/fs/namespace.c index 31d357450f7..ec8512478b0 100644 --- a/fs/namespace.c +++ b/fs/namespace.c @@ -1182,7 +1182,7 @@ void release_mounts(struct list_head *head) while (!list_empty(head)) { mnt = list_first_entry(head, struct vfsmount, mnt_hash); list_del_init(&mnt->mnt_hash); - if (mnt->mnt_parent != mnt) { + if (mnt_has_parent(mnt)) { struct dentry *dentry; struct vfsmount *m; @@ -1222,7 +1222,7 @@ void umount_tree(struct vfsmount *mnt, int propagate, struct list_head *kill) p->mnt_ns = NULL; __mnt_make_shortterm(p); list_del_init(&p->mnt_child); - if (p->mnt_parent != p) { + if (mnt_has_parent(p)) { p->mnt_parent->mnt_ghosts++; dentry_reset_mounted(p->mnt_parent, p->mnt_mountpoint); } @@ -1867,7 +1867,7 @@ static int do_move_mount(struct path *path, char *old_name) if (old_path.dentry != old_path.mnt->mnt_root) goto out1; - if (old_path.mnt == old_path.mnt->mnt_parent) + if (!mnt_has_parent(old_path.mnt)) goto out1; if (S_ISDIR(path->dentry->d_inode->i_mode) != @@ -1887,7 +1887,7 @@ static int do_move_mount(struct path *path, char *old_name) tree_contains_unbindable(old_path.mnt)) goto out1; err = -ELOOP; - for (p = path->mnt; p->mnt_parent != p; p = p->mnt_parent) + for (p = path->mnt; mnt_has_parent(p); p = p->mnt_parent) if (p == old_path.mnt) goto out1; @@ -2604,17 +2604,17 @@ SYSCALL_DEFINE2(pivot_root, const char __user *, new_root, error = -EINVAL; if (root.mnt->mnt_root != root.dentry) goto out4; /* not a mountpoint */ - if (root.mnt->mnt_parent == root.mnt) + if (!mnt_has_parent(root.mnt)) goto out4; /* not attached */ if (new.mnt->mnt_root != new.dentry) goto out4; /* not a mountpoint */ - if (new.mnt->mnt_parent == new.mnt) + if (!mnt_has_parent(new.mnt)) goto out4; /* not attached */ /* make sure we can reach put_old from new_root */ tmp = old.mnt; if (tmp != new.mnt) { for (;;) { - if (tmp->mnt_parent == tmp) + if (!mnt_has_parent(tmp)) goto out4; /* already mounted on put_old */ if (tmp->mnt_parent == new.mnt) break; |