jcs.org
Serenity Operating System
1/*
2 * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
3 *
4 * SPDX-License-Identifier: BSD-2-Clause
5 */
6
7#include <AK/Singleton.h>
8#include <Kernel/Devices/Device.h>
9#include <Kernel/Devices/DeviceManagement.h>
10#include <Kernel/FileSystem/InodeMetadata.h>
11#include <Kernel/FileSystem/SysFS/Component.h>
12#include <Kernel/FileSystem/SysFS/Subsystems/DeviceIdentifiers/BlockDevicesDirectory.h>
13#include <Kernel/FileSystem/SysFS/Subsystems/DeviceIdentifiers/CharacterDevicesDirectory.h>
14#include <Kernel/Sections.h>
15
16namespace Kernel {
17
18Device::Device(MajorNumber major, MinorNumber minor)
19 : m_major(major)
20 , m_minor(minor)
21{
22}
23
24void Device::before_will_be_destroyed_remove_from_device_management()
25{
26 DeviceManagement::the().before_device_removal({}, *this);
27 m_state = State::BeingRemoved;
28}
29
30void Device::after_inserting_add_to_device_management()
31{
32 DeviceManagement::the().after_inserting_device({}, *this);
33}
34
35ErrorOr<void> Device::after_inserting()
36{
37 after_inserting_add_to_device_management();
38 VERIFY(!m_sysfs_component);
39 auto sys_fs_component = SysFSDeviceComponent::must_create(*this);
40 m_sysfs_component = sys_fs_component;
41 after_inserting_add_to_device_identifier_directory();
42 return {};
43}
44
45void Device::will_be_destroyed()
46{
47 VERIFY(m_sysfs_component);
48 before_will_be_destroyed_remove_from_device_identifier_directory();
49 before_will_be_destroyed_remove_from_device_management();
50}
51
52Device::~Device()
53{
54 VERIFY(m_state == State::BeingRemoved);
55}
56
57ErrorOr<NonnullOwnPtr<KString>> Device::pseudo_path(OpenFileDescription const&) const
58{
59 return KString::formatted("device:{},{}", major(), minor());
60}
61
62ErrorOr<NonnullRefPtr<OpenFileDescription>> Device::open(int options)
63{
64 TRY(Process::current().jail().with([&](auto const& my_jail) -> ErrorOr<void> {
65 if (my_jail && !is_openable_by_jailed_processes())
66 return Error::from_errno(EPERM);
67 return {};
68 }));
69 return File::open(options);
70}
71
72void Device::process_next_queued_request(Badge<AsyncDeviceRequest>, AsyncDeviceRequest const& completed_request)
73{
74 SpinlockLocker lock(m_requests_lock);
75 VERIFY(!m_requests.is_empty());
76 VERIFY(m_requests.first().ptr() == &completed_request);
77 m_requests.remove(m_requests.begin());
78 if (!m_requests.is_empty()) {
79 auto* next_request = m_requests.first().ptr();
80 next_request->do_start(move(lock));
81 }
82
83 evaluate_block_conditions();
84}
85
86}