src/core/device.h

   1 /* SPDX-License-Identifier: LGPL-2.1+ */
   2 #pragma once
   3
   4 /***
   5   Copyright 2010 Lennart Poettering
   6 ***/
   7
   8 #include "unit.h"
   9
  10 typedef struct Device Device;
  11
  12 /* A mask specifying where we have seen the device currently. This is a bitmask because the device might show up
  13  * asynchronously from each other at various places. For example, in very common case a device might already be mounted
  14  * before udev finished probing it (think: a script setting up a loopback block device, formatting it and mounting it
  15  * in quick succession). Hence we need to track precisely where it is already visible and where not. */
  16 typedef enum DeviceFound {
  17         DEVICE_NOT_FOUND   = 0,
  18         DEVICE_FOUND_UDEV  = 1U << 1, /* The device has shown up in the udev database */
  19         DEVICE_FOUND_MOUNT = 1U << 2, /* The device has shown up in /proc/self/mountinfo */
  20         DEVICE_FOUND_SWAP  = 1U << 3, /* The device has shown up in /proc/swaps */
  21         DEVICE_FOUND_MASK  = DEVICE_FOUND_UDEV|DEVICE_FOUND_MOUNT|DEVICE_FOUND_SWAP,
  22 } DeviceFound;
  23
  24 struct Device {
  25         Unit meta;
  26
  27         char *sysfs;
  28
  29         /* In order to be able to distinguish dependencies on different device nodes we might end up creating multiple
  30          * devices for the same sysfs path. We chain them up here. */
  31         LIST_FIELDS(struct Device, same_sysfs);
  32
  33         DeviceState state, deserialized_state;
  34         DeviceFound found, deserialized_found, enumerated_found;
  35
  36         bool bind_mounts;
  37 };
  38
  39 extern const UnitVTable device_vtable;
  40
  41 void device_found_node(Manager *m, const char *node, DeviceFound found, DeviceFound mask);
  42 bool device_shall_be_bound_by(Unit *device, Unit *u);
  43
  44 DEFINE_CAST(DEVICE, Device);