static int automount_dispatch_io(sd_event_source *s, int fd, uint32_t events, void *userdata) {
union autofs_v5_packet_union packet;
Automount *a = AUTOMOUNT(userdata);
ssize_t l;
int r;
assert(a);
assert(fd == a->pipe_fd);
if (events != EPOLLIN) {
log_error_unit(UNIT(a)->id, "Got invalid poll event on pipe.");
goto fail;
}
l = loop_read(a->pipe_fd, &packet, sizeof(packet), true);
if (l != sizeof(packet)) {
log_error_unit(UNIT(a)->id, "Invalid read from pipe: %s", l < 0 ? strerror(-l) : "short read");
goto fail;
}
switch (packet.hdr.type) {
case autofs_ptype_missing_direct:
if (packet.v5_packet.pid > 0) {
_cleanup_free_ char *p = NULL;
get_process_comm(packet.v5_packet.pid, &p);
log_info_unit(UNIT(a)->id,
"Got automount request for %s, triggered by "PID_FMT" (%s)",
a->where, packet.v5_packet.pid, strna(p));
} else
log_debug_unit(UNIT(a)->id, "Got direct mount request on %s", a->where);
r = set_ensure_allocated(&a->tokens, trivial_hash_func, trivial_compare_func);
if (r < 0) {
log_error_unit(UNIT(a)->id, "Failed to allocate token set.");
goto fail;
}
r = set_put(a->tokens, UINT_TO_PTR(packet.v5_packet.wait_queue_token));
if (r < 0) {
log_error_unit(UNIT(a)->id, "Failed to remember token: %s", strerror(-r));
goto fail;
}
automount_enter_runnning(a);
break;
default:
log_error_unit(UNIT(a)->id, "Received unknown automount request %i", packet.hdr.type);
break;
}
return 0;
fail:
automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
return 0;
}
static int automount_verify(Automount *a) {
bool b;
char *e;
assert(a);
if (UNIT(a)->load_state != UNIT_LOADED)
return 0;
if (path_equal(a->where, "/")) {
log_error_unit(UNIT(a)->id, "Cannot have an automount unit for the root directory. Refusing.");
return -EINVAL;
}
e = unit_name_from_path(a->where, ".automount");
if (!e)
return -ENOMEM;
b = unit_has_name(UNIT(a), e);
free(e);
if (!b) {
log_error_unit(UNIT(a)->id, "%s's Where setting doesn't match unit name. Refusing.", UNIT(a)->id);
return -EINVAL;
}
return 0;
}
static int slice_verify(Slice *s) {
assert(s);
if (UNIT(s)->load_state != UNIT_LOADED)
return 0;
if (UNIT_DEREF(UNIT(s)->slice)) {
char *a, *dash;
a = strdupa(UNIT(s)->id);
dash = strrchr(a, '-');
if (dash)
strcpy(dash, ".slice");
else
a = (char*) SPECIAL_ROOT_SLICE;
if (!unit_has_name(UNIT_DEREF(UNIT(s)->slice), a)) {
log_error_unit(UNIT(s)->id,
"%s located outside its parent slice. Refusing.", UNIT(s)->id);
return -EINVAL;
}
}
return 0;
}
static int busname_verify(BusName *n) {
char *e;
assert(n);
if (UNIT(n)->load_state != UNIT_LOADED)
return 0;
if (!service_name_is_valid(n->name)) {
log_error_unit(UNIT(n)->id, "%s's Name= setting is not a valid service name Refusing.", UNIT(n)->id);
return -EINVAL;
}
e = strappenda(n->name, ".busname");
if (!unit_has_name(UNIT(n), e)) {
log_error_unit(UNIT(n)->id, "%s's Name= setting doesn't match unit name. Refusing.", UNIT(n)->id);
return -EINVAL;
}
return 0;
}
static int scope_verify(Scope *s) {
assert(s);
if (UNIT(s)->load_state != UNIT_LOADED)
return 0;
if (set_size(s->pids) <= 0 && UNIT(s)->manager->n_reloading <= 0) {
log_error_unit(UNIT(s)->id, "Scope %s has no PIDs. Refusing.", UNIT(s)->id);
return -EINVAL;
}
return 0;
}
static int automount_start(Unit *u) {
Automount *a = AUTOMOUNT(u);
assert(a);
assert(a->state == AUTOMOUNT_DEAD || a->state == AUTOMOUNT_FAILED);
if (path_is_mount_point(a->where, false)) {
log_error_unit(u->id,
"Path %s is already a mount point, refusing start for %s",
a->where, u->id);
return -EEXIST;
}
if (UNIT_TRIGGER(u)->load_state != UNIT_LOADED)
return -ENOENT;
a->result = AUTOMOUNT_SUCCESS;
automount_enter_waiting(a);
return 0;
}
static void automount_enter_waiting(Automount *a) {
int p[2] = { -1, -1 };
char name[32], options[128];
bool mounted = false;
int r, ioctl_fd = -1, dev_autofs_fd;
struct stat st;
assert(a);
assert(a->pipe_fd < 0);
assert(a->where);
if (a->tokens)
set_clear(a->tokens);
dev_autofs_fd = open_dev_autofs(UNIT(a)->manager);
if (dev_autofs_fd < 0) {
r = dev_autofs_fd;
goto fail;
}
/* We knowingly ignore the results of this call */
mkdir_p_label(a->where, 0555);
warn_if_dir_nonempty(a->meta.id, a->where);
if (pipe2(p, O_NONBLOCK|O_CLOEXEC) < 0) {
r = -errno;
goto fail;
}
snprintf(options, sizeof(options), "fd=%i,pgrp=%u,minproto=5,maxproto=5,direct", p[1], (unsigned) getpgrp());
char_array_0(options);
snprintf(name, sizeof(name), "systemd-%u", (unsigned) getpid());
char_array_0(name);
if (mount(name, a->where, "autofs", 0, options) < 0) {
r = -errno;
goto fail;
}
mounted = true;
close_nointr_nofail(p[1]);
p[1] = -1;
if (stat(a->where, &st) < 0) {
r = -errno;
goto fail;
}
ioctl_fd = open_ioctl_fd(dev_autofs_fd, a->where, st.st_dev);
if (ioctl_fd < 0) {
r = ioctl_fd;
goto fail;
}
r = autofs_protocol(dev_autofs_fd, ioctl_fd);
if (r < 0)
goto fail;
r = autofs_set_timeout(dev_autofs_fd, ioctl_fd, 300);
if (r < 0)
goto fail;
/* Autofs fun fact:
*
* Unless we close the ioctl fd here, for some weird reason
* the direct mount will not receive events from the
* kernel. */
close_nointr_nofail(ioctl_fd);
ioctl_fd = -1;
r = sd_event_add_io(UNIT(a)->manager->event, p[0], EPOLLIN, automount_dispatch_io, a, &a->pipe_event_source);
if (r < 0)
goto fail;
a->pipe_fd = p[0];
a->dev_id = st.st_dev;
automount_set_state(a, AUTOMOUNT_WAITING);
return;
fail:
assert_se(close_pipe(p) == 0);
if (ioctl_fd >= 0)
close_nointr_nofail(ioctl_fd);
if (mounted)
repeat_unmount(a->where);
log_error_unit(UNIT(a)->id,
"Failed to initialize automounter: %s", strerror(-r));
automount_enter_dead(a, AUTOMOUNT_FAILURE_RESOURCES);
}
