Atmosphere/libraries/libmesosphere/include/mesosphere/kern_k_handle_table.hpp
2020-12-02 06:43:37 -08:00

365 lines
14 KiB
C++

/*
* Copyright (c) 2018-2020 Atmosphère-NX
*
* This program is free software; you can redistribute it and/or modify it
* under the terms and conditions of the GNU General Public License,
* version 2, as published by the Free Software Foundation.
*
* This program is distributed in the hope it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
* more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#pragma once
#include <mesosphere/kern_common.hpp>
#include <mesosphere/kern_k_auto_object.hpp>
#include <mesosphere/kern_k_spin_lock.hpp>
#include <mesosphere/kern_k_thread.hpp>
#include <mesosphere/kern_k_interrupt_event.hpp>
namespace ams::kern {
constexpr ALWAYS_INLINE util::BitPack32 GetHandleBitPack(ams::svc::Handle handle) {
return util::BitPack32{handle};
}
class KProcess;
class KThread;
class KHandleTable {
NON_COPYABLE(KHandleTable);
NON_MOVEABLE(KHandleTable);
public:
static constexpr size_t MaxTableSize = 1024;
private:
using HandleRawValue = util::BitPack32::Field<0, BITSIZEOF(u32), u32>;
using HandleEncoded = util::BitPack32::Field<0, BITSIZEOF(ams::svc::Handle), ams::svc::Handle>;
using HandleIndex = util::BitPack32::Field<0, 15, u16>;
using HandleLinearId = util::BitPack32::Field<HandleIndex::Next, 15, u16>;
using HandleReserved = util::BitPack32::Field<HandleLinearId::Next, 2, u32>;
static constexpr u16 MinLinearId = 1;
static constexpr u16 MaxLinearId = util::BitPack32{std::numeric_limits<u32>::max()}.Get<HandleLinearId>();
static constexpr ALWAYS_INLINE ams::svc::Handle EncodeHandle(u16 index, u16 linear_id) {
util::BitPack32 pack = {0};
pack.Set<HandleIndex>(index);
pack.Set<HandleLinearId>(linear_id);
pack.Set<HandleReserved>(0);
return pack.Get<HandleEncoded>();
}
class Entry {
private:
union {
struct {
u16 linear_id;
u16 type;
} info;
Entry *next_free_entry;
} meta;
KAutoObject *object;
public:
constexpr Entry() : meta(), object(nullptr) { /* ... */ }
constexpr ALWAYS_INLINE void SetFree(Entry *next) {
this->object = nullptr;
this->meta.next_free_entry = next;
}
constexpr ALWAYS_INLINE void SetUsed(KAutoObject *obj, u16 linear_id, u16 type) {
this->object = obj;
this->meta.info = { linear_id, type };
}
constexpr ALWAYS_INLINE KAutoObject *GetObject() const { return this->object; }
constexpr ALWAYS_INLINE Entry *GetNextFreeEntry() const { return this->meta.next_free_entry; }
constexpr ALWAYS_INLINE u16 GetLinearId() const { return this->meta.info.linear_id; }
constexpr ALWAYS_INLINE u16 GetType() const { return this->meta.info.type; }
};
private:
mutable KSpinLock lock;
Entry *table;
Entry *free_head;
Entry entries[MaxTableSize];
u16 table_size;
u16 max_count;
u16 next_linear_id;
u16 count;
public:
constexpr KHandleTable() :
lock(), table(nullptr), free_head(nullptr), entries(), table_size(0), max_count(0), next_linear_id(MinLinearId), count(0)
{ MESOSPHERE_ASSERT_THIS(); }
constexpr NOINLINE Result Initialize(s32 size) {
MESOSPHERE_ASSERT_THIS();
R_UNLESS(size <= static_cast<s32>(MaxTableSize), svc::ResultOutOfMemory());
/* Initialize all fields. */
this->table = this->entries;
this->table_size = (size <= 0) ? MaxTableSize : size;
this->next_linear_id = MinLinearId;
this->count = 0;
this->max_count = 0;
/* Free all entries. */
for (size_t i = 0; i < static_cast<size_t>(this->table_size - 1); i++) {
this->entries[i].SetFree(std::addressof(this->entries[i + 1]));
}
this->entries[this->table_size - 1].SetFree(nullptr);
this->free_head = std::addressof(this->entries[0]);
return ResultSuccess();
}
constexpr ALWAYS_INLINE size_t GetTableSize() const { return this->table_size; }
constexpr ALWAYS_INLINE size_t GetCount() const { return this->count; }
constexpr ALWAYS_INLINE size_t GetMaxCount() const { return this->max_count; }
NOINLINE Result Finalize();
NOINLINE bool Remove(ams::svc::Handle handle);
template<typename T = KAutoObject>
ALWAYS_INLINE KScopedAutoObject<T> GetObjectWithoutPseudoHandle(ams::svc::Handle handle) const {
/* Lock and look up in table. */
KScopedDisableDispatch dd;
KScopedSpinLock lk(this->lock);
if constexpr (std::is_same<T, KAutoObject>::value) {
return this->GetObjectImpl(handle);
} else {
if (auto *obj = this->GetObjectImpl(handle); obj != nullptr) {
return obj->DynamicCast<T*>();
} else {
return nullptr;
}
}
}
template<typename T = KAutoObject>
ALWAYS_INLINE KScopedAutoObject<T> GetObject(ams::svc::Handle handle) const {
MESOSPHERE_ASSERT_THIS();
/* Handle pseudo-handles. */
if constexpr (std::derived_from<KProcess, T>) {
if (handle == ams::svc::PseudoHandle::CurrentProcess) {
return GetCurrentProcessPointer();
}
} else if constexpr (std::derived_from<KThread, T>) {
if (handle == ams::svc::PseudoHandle::CurrentThread) {
return GetCurrentThreadPointer();
}
}
return this->template GetObjectWithoutPseudoHandle<T>(handle);
}
KScopedAutoObject<KAutoObject> GetObjectForIpcWithoutPseudoHandle(ams::svc::Handle handle) const {
/* Lock and look up in table. */
KScopedDisableDispatch dd;
KScopedSpinLock lk(this->lock);
KAutoObject *obj = this->GetObjectImpl(handle);
if (AMS_LIKELY(obj != nullptr)) {
if (AMS_UNLIKELY(obj->DynamicCast<KInterruptEvent *>() != nullptr)) {
return nullptr;
}
}
return obj;
}
ALWAYS_INLINE KScopedAutoObject<KAutoObject> GetObjectForIpc(ams::svc::Handle handle, KThread *cur_thread) const {
/* Handle pseudo-handles. */
if (handle == ams::svc::PseudoHandle::CurrentProcess) {
return static_cast<KAutoObject *>(static_cast<void *>(cur_thread->GetOwnerProcess()));
}
if (handle == ams::svc::PseudoHandle::CurrentThread) {
return static_cast<KAutoObject *>(cur_thread);
}
return GetObjectForIpcWithoutPseudoHandle(handle);
}
ALWAYS_INLINE KScopedAutoObject<KAutoObject> GetObjectByIndex(ams::svc::Handle *out_handle, size_t index) const {
MESOSPHERE_ASSERT_THIS();
KScopedDisableDispatch dd;
KScopedSpinLock lk(this->lock);
return this->GetObjectByIndexImpl(out_handle, index);
}
NOINLINE Result Reserve(ams::svc::Handle *out_handle);
NOINLINE void Unreserve(ams::svc::Handle handle);
template<typename T>
ALWAYS_INLINE Result Add(ams::svc::Handle *out_handle, T *obj) {
static_assert(std::is_base_of<KAutoObject, T>::value);
return this->Add(out_handle, obj, obj->GetTypeObj().GetClassToken());
}
template<typename T>
ALWAYS_INLINE void Register(ams::svc::Handle handle, T *obj) {
static_assert(std::is_base_of<KAutoObject, T>::value);
return this->Register(handle, obj, obj->GetTypeObj().GetClassToken());
}
template<typename T>
ALWAYS_INLINE bool GetMultipleObjects(T **out, const ams::svc::Handle *handles, size_t num_handles) const {
/* Try to convert and open all the handles. */
size_t num_opened;
{
/* Lock the table. */
KScopedDisableDispatch dd;
KScopedSpinLock lk(this->lock);
for (num_opened = 0; num_opened < num_handles; num_opened++) {
/* Get the current handle. */
const auto cur_handle = handles[num_opened];
/* Get the object for the current handle. */
KAutoObject *cur_object = this->GetObjectImpl(cur_handle);
if (AMS_UNLIKELY(cur_object == nullptr)) {
break;
}
/* Cast the current object to the desired type. */
T *cur_t = cur_object->DynamicCast<T*>();
if (AMS_UNLIKELY(cur_t == nullptr)) {
break;
}
/* Open a reference to the current object. */
cur_t->Open();
out[num_opened] = cur_t;
}
}
/* If we converted every object, succeed. */
if (AMS_LIKELY(num_opened == num_handles)) {
return true;
}
/* If we didn't convert entry object, close the ones we opened. */
for (size_t i = 0; i < num_opened; i++) {
out[i]->Close();
}
return false;
}
private:
NOINLINE Result Add(ams::svc::Handle *out_handle, KAutoObject *obj, u16 type);
NOINLINE void Register(ams::svc::Handle handle, KAutoObject *obj, u16 type);
constexpr ALWAYS_INLINE Entry *AllocateEntry() {
MESOSPHERE_ASSERT_THIS();
MESOSPHERE_ASSERT(this->count < this->table_size);
Entry *entry = this->free_head;
this->free_head = entry->GetNextFreeEntry();
this->count++;
this->max_count = std::max(this->max_count, this->count);
return entry;
}
constexpr ALWAYS_INLINE void FreeEntry(Entry *entry) {
MESOSPHERE_ASSERT_THIS();
MESOSPHERE_ASSERT(this->count > 0);
entry->SetFree(this->free_head);
this->free_head = entry;
this->count--;
}
constexpr ALWAYS_INLINE u16 AllocateLinearId() {
const u16 id = this->next_linear_id++;
if (this->next_linear_id > MaxLinearId) {
this->next_linear_id = MinLinearId;
}
return id;
}
constexpr ALWAYS_INLINE size_t GetEntryIndex(Entry *entry) {
const size_t index = entry - this->table;
MESOSPHERE_ASSERT(index < this->table_size);
return index;
}
constexpr ALWAYS_INLINE Entry *FindEntry(ams::svc::Handle handle) const {
MESOSPHERE_ASSERT_THIS();
/* Unpack the handle. */
const auto handle_pack = GetHandleBitPack(handle);
const auto raw_value = handle_pack.Get<HandleRawValue>();
const auto index = handle_pack.Get<HandleIndex>();
const auto linear_id = handle_pack.Get<HandleLinearId>();
const auto reserved = handle_pack.Get<HandleReserved>();
MESOSPHERE_ASSERT(reserved == 0);
/* Validate our indexing information. */
if (raw_value == 0) {
return nullptr;
}
if (linear_id == 0) {
return nullptr;
}
if (index >= this->table_size) {
return nullptr;
}
/* Get the entry, and ensure our serial id is correct. */
Entry *entry = std::addressof(this->table[index]);
if (entry->GetObject() == nullptr) {
return nullptr;
}
if (entry->GetLinearId() != linear_id) {
return nullptr;
}
return entry;
}
constexpr ALWAYS_INLINE KAutoObject *GetObjectImpl(ams::svc::Handle handle) const {
MESOSPHERE_ASSERT_THIS();
/* Handles must not have reserved bits set. */
if (GetHandleBitPack(handle).Get<HandleReserved>() != 0) {
return nullptr;
}
if (Entry *entry = this->FindEntry(handle); entry != nullptr) {
return entry->GetObject();
} else {
return nullptr;
}
}
constexpr ALWAYS_INLINE KAutoObject *GetObjectByIndexImpl(ams::svc::Handle *out_handle, size_t index) const {
MESOSPHERE_ASSERT_THIS();
/* Index must be in bounds. */
if (index >= this->table_size || this->table == nullptr) {
return nullptr;
}
/* Ensure entry has an object. */
Entry *entry = std::addressof(this->table[index]);
if (entry->GetObject() == nullptr) {
return nullptr;
}
*out_handle = EncodeHandle(index, entry->GetLinearId());
return entry->GetObject();
}
};
}