/*
* Check if the given path is a mountpoint.
*
* If we are supplied with the file descriptor of an autofs
* mount we're looking for a specific mount. In this case
* the path is considered a mountpoint if it is itself a
* mountpoint or contains a mount, such as a multi-mount
* without a root mount. In this case we return 1 if the
* path is a mount point and the super magic of the covering
* mount if there is one or 0 if it isn't a mountpoint.
*
* If we aren't supplied with a file descriptor then we
* lookup the nameidata of the path and check if it is the
* root of a mount. If a type is given we are looking for
* a particular autofs mount and if we don't find a match
* we return fail. If the located nameidata path is the
* root of a mount we return 1 along with the super magic
* of the mount or 0 otherwise.
*
* In both cases the the device number (as returned by
* new_encode_dev()) is also returned.
*/
static int autofs_dev_ioctl_ismountpoint(struct file *fp,
struct autofs_sb_info *sbi,
struct autofs_dev_ioctl *param)
{
struct path path;
const char *name;
unsigned int type;
unsigned int devid, magic;
int err = -ENOENT;
if (param->size <= sizeof(*param)) {
err = -EINVAL;
goto out;
}
name = param->path;
type = param->ismountpoint.in.type;
param->ismountpoint.out.devid = devid = 0;
param->ismountpoint.out.magic = magic = 0;
if (!fp || param->ioctlfd == -1) {
if (autofs_type_any(type))
err = kern_path(name, LOOKUP_FOLLOW, &path);
else
err = find_autofs_mount(name, &path, test_by_type, &type);
if (err)
goto out;
devid = new_encode_dev(path.mnt->mnt_sb->s_dev);
err = 0;
if (path.dentry->d_inode &&
path.mnt->mnt_root == path.dentry) {
err = 1;
magic = path.dentry->d_inode->i_sb->s_magic;
}
} else {
dev_t dev = sbi->sb->s_dev;
err = find_autofs_mount(name, &path, test_by_dev, &dev);
if (err)
goto out;
devid = new_encode_dev(dev);
err = have_submounts(path.dentry);
if (path.mnt->mnt_mountpoint != path.mnt->mnt_root) {
if (follow_down(&path))
magic = path.mnt->mnt_sb->s_magic;
}
}
param->ismountpoint.out.devid = devid;
param->ismountpoint.out.magic = magic;
path_put(&path);
out:
return err;
}
/*
* Check if the given path is a mountpoint.
*
* If we are supplied with the file descriptor of an autofs
* mount we're looking for a specific mount. In this case
* the path is considered a mountpoint if it is itself a
* mountpoint or contains a mount, such as a multi-mount
* without a root mount. In this case we return 1 if the
* path is a mount point and the super magic of the covering
* mount if there is one or 0 if it isn't a mountpoint.
*
* If we aren't supplied with a file descriptor then we
* lookup the path and check if it is the root of a mount.
* If a type is given we are looking for a particular autofs
* mount and if we don't find a match we return fail. If the
* located path is the root of a mount we return 1 along with
* the super magic of the mount or 0 otherwise.
*
* In both cases the the device number (as returned by
* new_encode_dev()) is also returned.
*/
static int autofs_dev_ioctl_ismountpoint(struct file *fp,
struct autofs_sb_info *sbi,
struct autofs_dev_ioctl *param)
{
struct path path;
const char *name;
unsigned int type;
unsigned int devid, magic;
int err = -ENOENT;
/* param->path has been checked in validate_dev_ioctl() */
name = param->path;
type = param->ismountpoint.in.type;
param->ismountpoint.out.devid = devid = 0;
param->ismountpoint.out.magic = magic = 0;
if (!fp || param->ioctlfd == -1) {
if (autofs_type_any(type))
err = kern_path_mountpoint(AT_FDCWD,
name, &path, LOOKUP_FOLLOW);
else
err = find_autofs_mount(name, &path,
test_by_type, &type);
if (err)
goto out;
devid = new_encode_dev(path.dentry->d_sb->s_dev);
err = 0;
if (path.mnt->mnt_root == path.dentry) {
err = 1;
magic = path.dentry->d_sb->s_magic;
}
} else {
dev_t dev = sbi->sb->s_dev;
err = find_autofs_mount(name, &path, test_by_dev, &dev);
if (err)
goto out;
devid = new_encode_dev(dev);
err = path_has_submounts(&path);
if (follow_down_one(&path))
magic = path.dentry->d_sb->s_magic;
}
param->ismountpoint.out.devid = devid;
param->ismountpoint.out.magic = magic;
path_put(&path);
out:
return err;
}
/*
* Check if the given path is a mountpoint.
*
* If we are supplied with the file descriptor of an autofs
* mount we're looking for a specific mount. In this case
* the path is considered a mountpoint if it is itself a
* mountpoint or contains a mount, such as a multi-mount
* without a root mount. In this case we return 1 if the
* path is a mount point and the super magic of the covering
* mount if there is one or 0 if it isn't a mountpoint.
*
* If we aren't supplied with a file descriptor then we
* lookup the nameidata of the path and check if it is the
* root of a mount. If a type is given we are looking for
* a particular autofs mount and if we don't find a match
* we return fail. If the located nameidata path is the
* root of a mount we return 1 along with the super magic
* of the mount or 0 otherwise.
*
* In both cases the the device number (as returned by
* new_encode_dev()) is also returned.
*/
static int autofs_dev_ioctl_ismountpoint(struct file *fp,
struct autofs_sb_info *sbi,
struct autofs_dev_ioctl *param)
{
struct nameidata nd;
const char *path;
unsigned int type;
unsigned int devid, magic;
int err = -ENOENT;
if (param->size <= sizeof(*param)) {
err = -EINVAL;
goto out;
}
path = param->path;
type = param->ismountpoint.in.type;
param->ismountpoint.out.devid = devid = 0;
param->ismountpoint.out.magic = magic = 0;
if (!fp || param->ioctlfd == -1) {
if (autofs_type_any(type)) {
struct super_block *sb;
err = path_lookup(path, LOOKUP_FOLLOW, &nd);
if (err)
goto out;
sb = nd.path.dentry->d_sb;
devid = new_encode_dev(sb->s_dev);
} else {
struct autofs_info *ino;
err = path_lookup(path, LOOKUP_PARENT, &nd);
if (err)
goto out;
err = autofs_dev_ioctl_find_sbi_type(&nd, type);
if (err)
goto out_release;
ino = autofs4_dentry_ino(nd.path.dentry);
devid = autofs4_get_dev(ino->sbi);
}
err = 0;
if (nd.path.dentry->d_inode &&
nd.path.mnt->mnt_root == nd.path.dentry) {
err = 1;
magic = nd.path.dentry->d_inode->i_sb->s_magic;
}
} else {
dev_t dev = autofs4_get_dev(sbi);
err = path_lookup(path, LOOKUP_PARENT, &nd);
if (err)
goto out;
err = autofs_dev_ioctl_find_super(&nd, dev);
if (err)
goto out_release;
devid = dev;
err = have_submounts(nd.path.dentry);
if (nd.path.mnt->mnt_mountpoint != nd.path.mnt->mnt_root) {
if (follow_down(&nd.path.mnt, &nd.path.dentry)) {
struct inode *inode = nd.path.dentry->d_inode;
magic = inode->i_sb->s_magic;
}
}
}
param->ismountpoint.out.devid = devid;
param->ismountpoint.out.magic = magic;
out_release:
path_put(&nd.path);
out:
return err;
}
