ladybird/Kernel/ProcessSpecificExposed.cpp
Andreas Kling 79fa9765ca Kernel: Replace KResult and KResultOr<T> with Error and ErrorOr<T>
We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace!
This was a slightly tedious refactoring that took a long time, so it's
not unlikely that some bugs crept in.

Nevertheless, it does pass basic functionality testing, and it's just
real nice to finally see the same pattern in all contexts. :^)
2021-11-08 01:10:53 +01:00

281 lines
11 KiB
C++

/*
* Copyright (c) 2021, Liav A. <liavalb@hotmail.co.il>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/JsonArraySerializer.h>
#include <AK/JsonObjectSerializer.h>
#include <AK/JsonValue.h>
#include <Kernel/Arch/x86/InterruptDisabler.h>
#include <Kernel/FileSystem/Custody.h>
#include <Kernel/FileSystem/ProcFS.h>
#include <Kernel/KBufferBuilder.h>
#include <Kernel/Memory/AnonymousVMObject.h>
#include <Kernel/Memory/MemoryManager.h>
#include <Kernel/Process.h>
#include <Kernel/ProcessExposed.h>
namespace Kernel {
ErrorOr<size_t> Process::procfs_get_thread_stack(ThreadID thread_id, KBufferBuilder& builder) const
{
JsonArraySerializer array { builder };
auto thread = Thread::from_tid(thread_id);
if (!thread)
return Error::from_errno(ESRCH);
bool show_kernel_addresses = Process::current().is_superuser();
bool kernel_address_added = false;
for (auto address : Processor::capture_stack_trace(*thread, 1024)) {
if (!show_kernel_addresses && !Memory::is_user_address(VirtualAddress { address })) {
if (kernel_address_added)
continue;
address = 0xdeadc0de;
kernel_address_added = true;
}
array.add(address);
}
array.finish();
// FIXME: This return value seems useless.
return 0;
}
ErrorOr<void> Process::traverse_stacks_directory(unsigned fsid, Function<bool(FileSystem::DirectoryEntryView const&)> callback) const
{
callback({ ".", { fsid, SegmentedProcFSIndex::build_segmented_index_for_main_property(pid(), SegmentedProcFSIndex::ProcessSubDirectory::Stacks, SegmentedProcFSIndex::MainProcessProperty::Reserved) }, 0 });
callback({ "..", { fsid, m_procfs_traits->component_index() }, 0 });
for_each_thread([&](const Thread& thread) {
int tid = thread.tid().value();
InodeIdentifier identifier = { fsid, SegmentedProcFSIndex::build_segmented_index_for_thread_stack(pid(), thread.tid()) };
callback({ String::number(tid), identifier, 0 });
});
return {};
}
ErrorOr<NonnullRefPtr<Inode>> Process::lookup_stacks_directory(const ProcFS& procfs, StringView name) const
{
ErrorOr<NonnullRefPtr<ProcFSProcessPropertyInode>> thread_stack_inode { ENOENT };
// FIXME: Try to exit the loop earlier
for_each_thread([&](const Thread& thread) {
int tid = thread.tid().value();
VERIFY(!(tid < 0));
if (name.to_int() == tid) {
auto maybe_inode = ProcFSProcessPropertyInode::try_create_for_thread_stack(procfs, thread.tid(), pid());
if (maybe_inode.is_error()) {
thread_stack_inode = maybe_inode.release_error();
return;
}
thread_stack_inode = maybe_inode.release_value();
}
});
if (thread_stack_inode.is_error())
return thread_stack_inode.release_error();
return thread_stack_inode.release_value();
}
ErrorOr<size_t> Process::procfs_get_file_description_link(unsigned fd, KBufferBuilder& builder) const
{
auto file_description = TRY(m_fds.open_file_description(fd));
// Note: These links are not guaranteed to point to actual VFS paths, just like in other kernels.
auto data = TRY(file_description->pseudo_path());
TRY(builder.append(data->view()));
return data->length();
}
ErrorOr<void> Process::traverse_file_descriptions_directory(unsigned fsid, Function<bool(FileSystem::DirectoryEntryView const&)> callback) const
{
callback({ ".", { fsid, m_procfs_traits->component_index() }, 0 });
callback({ "..", { fsid, m_procfs_traits->component_index() }, 0 });
size_t count = 0;
fds().enumerate([&](auto& file_description_metadata) {
if (!file_description_metadata.is_valid()) {
count++;
return;
}
StringBuilder builder;
builder.appendff("{}", count);
callback({ builder.string_view(), { fsid, SegmentedProcFSIndex::build_segmented_index_for_file_description(pid(), count) }, DT_LNK });
count++;
});
return {};
}
ErrorOr<NonnullRefPtr<Inode>> Process::lookup_file_descriptions_directory(const ProcFS& procfs, StringView name) const
{
auto maybe_index = name.to_uint();
if (!maybe_index.has_value())
return ENOENT;
if (!fds().get_if_valid(*maybe_index))
return ENOENT;
return TRY(ProcFSProcessPropertyInode::try_create_for_file_description_link(procfs, *maybe_index, pid()));
}
ErrorOr<void> Process::procfs_get_pledge_stats(KBufferBuilder& builder) const
{
JsonObjectSerializer obj { builder };
#define __ENUMERATE_PLEDGE_PROMISE(x) \
if (has_promised(Pledge::x)) { \
if (!builder.is_empty()) \
builder.append(' '); \
builder.append(#x); \
}
if (has_promises()) {
StringBuilder builder;
ENUMERATE_PLEDGE_PROMISES
obj.add("promises", builder.build());
}
#undef __ENUMERATE_PLEDGE_PROMISE
obj.finish();
return {};
}
ErrorOr<void> Process::procfs_get_unveil_stats(KBufferBuilder& builder) const
{
JsonArraySerializer array { builder };
for (auto& unveiled_path : unveiled_paths()) {
if (!unveiled_path.was_explicitly_unveiled())
continue;
auto obj = array.add_object();
obj.add("path", unveiled_path.path());
StringBuilder permissions_builder;
if (unveiled_path.permissions() & UnveilAccess::Read)
permissions_builder.append('r');
if (unveiled_path.permissions() & UnveilAccess::Write)
permissions_builder.append('w');
if (unveiled_path.permissions() & UnveilAccess::Execute)
permissions_builder.append('x');
if (unveiled_path.permissions() & UnveilAccess::CreateOrRemove)
permissions_builder.append('c');
if (unveiled_path.permissions() & UnveilAccess::Browse)
permissions_builder.append('b');
obj.add("permissions", permissions_builder.to_string());
}
array.finish();
return {};
}
ErrorOr<void> Process::procfs_get_perf_events(KBufferBuilder& builder) const
{
InterruptDisabler disabler;
if (!perf_events()) {
dbgln("ProcFS: No perf events for {}", pid());
return Error::from_errno(ENOBUFS);
}
return perf_events()->to_json(builder);
}
ErrorOr<void> Process::procfs_get_fds_stats(KBufferBuilder& builder) const
{
JsonArraySerializer array { builder };
if (fds().open_count() == 0) {
array.finish();
return {};
}
size_t count = 0;
fds().enumerate([&](auto& file_description_metadata) {
if (!file_description_metadata.is_valid()) {
count++;
return;
}
bool cloexec = file_description_metadata.flags() & FD_CLOEXEC;
RefPtr<OpenFileDescription> description = file_description_metadata.description();
auto description_object = array.add_object();
description_object.add("fd", count);
// TODO: Better OOM handling.
auto pseudo_path_or_error = description->pseudo_path();
description_object.add("absolute_path", pseudo_path_or_error.is_error() ? "???"sv : pseudo_path_or_error.value()->view());
description_object.add("seekable", description->file().is_seekable());
description_object.add("class", description->file().class_name());
description_object.add("offset", description->offset());
description_object.add("cloexec", cloexec);
description_object.add("blocking", description->is_blocking());
description_object.add("can_read", description->can_read());
description_object.add("can_write", description->can_write());
Inode* inode = description->inode();
if (inode != nullptr) {
auto inode_object = description_object.add_object("inode");
inode_object.add("fsid", inode->fsid());
inode_object.add("index", inode->index().value());
inode_object.finish();
}
count++;
});
array.finish();
return {};
}
ErrorOr<void> Process::procfs_get_virtual_memory_stats(KBufferBuilder& builder) const
{
JsonArraySerializer array { builder };
{
SpinlockLocker lock(address_space().get_lock());
for (auto& region : address_space().regions()) {
if (!region->is_user() && !Process::current().is_superuser())
continue;
auto region_object = array.add_object();
region_object.add("readable", region->is_readable());
region_object.add("writable", region->is_writable());
region_object.add("executable", region->is_executable());
region_object.add("stack", region->is_stack());
region_object.add("shared", region->is_shared());
region_object.add("syscall", region->is_syscall_region());
region_object.add("purgeable", region->vmobject().is_anonymous());
if (region->vmobject().is_anonymous()) {
region_object.add("volatile", static_cast<Memory::AnonymousVMObject const&>(region->vmobject()).is_volatile());
}
region_object.add("cacheable", region->is_cacheable());
region_object.add("address", region->vaddr().get());
region_object.add("size", region->size());
region_object.add("amount_resident", region->amount_resident());
region_object.add("amount_dirty", region->amount_dirty());
region_object.add("cow_pages", region->cow_pages());
region_object.add("name", region->name());
region_object.add("vmobject", region->vmobject().class_name());
StringBuilder pagemap_builder;
for (size_t i = 0; i < region->page_count(); ++i) {
auto* page = region->physical_page(i);
if (!page)
pagemap_builder.append('N');
else if (page->is_shared_zero_page() || page->is_lazy_committed_page())
pagemap_builder.append('Z');
else
pagemap_builder.append('P');
}
region_object.add("pagemap", pagemap_builder.to_string());
}
}
array.finish();
return {};
}
ErrorOr<void> Process::procfs_get_current_work_directory_link(KBufferBuilder& builder) const
{
return builder.append_bytes(const_cast<Process&>(*this).current_directory().absolute_path().bytes());
}
mode_t Process::binary_link_required_mode() const
{
if (!executable())
return 0;
return m_procfs_traits->required_mode();
}
ErrorOr<void> Process::procfs_get_binary_link(KBufferBuilder& builder) const
{
auto* custody = executable();
if (!custody)
return Error::from_errno(ENOEXEC);
return builder.append(custody->absolute_path().bytes());
}
}