Atmosphere/libraries/libmesosphere/source/arch/arm64/kern_k_page_table.cpp
2024-10-10 15:29:29 -07:00

1032 lines
50 KiB
C++

/*
* Copyright (c) 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/>.
*/
#include <mesosphere.hpp>
namespace ams::kern::arch::arm64 {
namespace {
class AlignedMemoryBlock {
private:
uintptr_t m_before_start;
uintptr_t m_before_end;
uintptr_t m_after_start;
uintptr_t m_after_end;
size_t m_current_alignment;
public:
constexpr AlignedMemoryBlock(uintptr_t start, size_t num_pages, size_t alignment) : m_before_start(0), m_before_end(0), m_after_start(0), m_after_end(0), m_current_alignment(0) {
MESOSPHERE_ASSERT(util::IsAligned(start, PageSize));
MESOSPHERE_ASSERT(num_pages > 0);
/* Find an alignment that allows us to divide into at least two regions.*/
uintptr_t start_page = start / PageSize;
alignment /= PageSize;
while (util::AlignUp(start_page, alignment) >= util::AlignDown(start_page + num_pages, alignment)) {
alignment = KPageTable::GetSmallerAlignment(alignment * PageSize) / PageSize;
}
m_before_start = start_page;
m_before_end = util::AlignUp(start_page, alignment);
m_after_start = m_before_end;
m_after_end = start_page + num_pages;
m_current_alignment = alignment;
MESOSPHERE_ASSERT(m_current_alignment > 0);
}
constexpr void SetAlignment(size_t alignment) {
/* We can only ever decrease the granularity. */
MESOSPHERE_ASSERT(m_current_alignment >= alignment / PageSize);
m_current_alignment = alignment / PageSize;
}
constexpr size_t GetAlignment() const {
return m_current_alignment * PageSize;
}
constexpr void FindBlock(uintptr_t &out, size_t &num_pages) {
if ((m_after_end - m_after_start) >= m_current_alignment) {
/* Select aligned memory from after block. */
const size_t available_pages = util::AlignDown(m_after_end, m_current_alignment) - m_after_start;
if (num_pages == 0 || available_pages < num_pages) {
num_pages = available_pages;
}
out = m_after_start * PageSize;
m_after_start += num_pages;
} else if ((m_before_end - m_before_start) >= m_current_alignment) {
/* Select aligned memory from before block. */
const size_t available_pages = m_before_end - util::AlignUp(m_before_start, m_current_alignment);
if (num_pages == 0 || available_pages < num_pages) {
num_pages = available_pages;
}
m_before_end -= num_pages;
out = m_before_end * PageSize;
} else {
/* Neither after or before can get an aligned bit of memory. */
out = 0;
num_pages = 0;
}
}
};
constexpr u64 EncodeTtbr(KPhysicalAddress table, u8 asid) {
return (static_cast<u64>(asid) << 48) | (static_cast<u64>(GetInteger(table)));
}
}
ALWAYS_INLINE void KPageTable::NoteUpdated() const {
cpu::DataSynchronizationBarrierInnerShareableStore();
/* Mark ourselves as in a tlb maintenance operation. */
GetCurrentThread().SetInTlbMaintenanceOperation();
ON_SCOPE_EXIT { GetCurrentThread().ClearInTlbMaintenanceOperation(); __asm__ __volatile__("" ::: "memory"); };
if (this->IsKernel()) {
this->OnKernelTableUpdated();
} else {
this->OnTableUpdated();
}
}
ALWAYS_INLINE void KPageTable::NoteSingleKernelPageUpdated(KProcessAddress virt_addr) const {
MESOSPHERE_ASSERT(this->IsKernel());
cpu::DataSynchronizationBarrierInnerShareableStore();
/* Mark ourselves as in a tlb maintenance operation. */
GetCurrentThread().SetInTlbMaintenanceOperation();
ON_SCOPE_EXIT { GetCurrentThread().ClearInTlbMaintenanceOperation(); __asm__ __volatile__("" ::: "memory"); };
this->OnKernelTableSinglePageUpdated(virt_addr);
}
void KPageTable::Initialize(s32 core_id) {
/* Nothing actually needed here. */
MESOSPHERE_UNUSED(core_id);
}
Result KPageTable::InitializeForKernel(void *table, KVirtualAddress start, KVirtualAddress end) {
/* Initialize basic fields. */
m_asid = 0;
m_manager = Kernel::GetSystemSystemResource().GetPageTableManagerPointer();
/* Initialize the base page table. */
MESOSPHERE_R_ABORT_UNLESS(KPageTableBase::InitializeForKernel(true, table, start, end));
R_SUCCEED();
}
Result KPageTable::InitializeForProcess(ams::svc::CreateProcessFlag flags, bool from_back, KMemoryManager::Pool pool, KProcessAddress code_address, size_t code_size, KSystemResource *system_resource, KResourceLimit *resource_limit, size_t process_index) {
/* Determine our ASID */
m_asid = process_index + 1;
MESOSPHERE_ABORT_UNLESS(0 < m_asid && m_asid < util::size(s_ttbr0_entries));
/* Set our manager. */
m_manager = system_resource->GetPageTableManagerPointer();
/* Get the virtual address of our L1 table. */
const KPhysicalAddress ttbr0_phys = KPhysicalAddress(s_ttbr0_entries[m_asid] & UINT64_C(0xFFFFFFFFFFFE));
const KVirtualAddress ttbr0_virt = KMemoryLayout::GetLinearVirtualAddress(ttbr0_phys);
/* Initialize our base table. */
const size_t as_width = GetAddressSpaceWidth(flags);
const KProcessAddress as_start = 0;
const KProcessAddress as_end = (1ul << as_width);
R_TRY(KPageTableBase::InitializeForProcess(flags, from_back, pool, GetVoidPointer(ttbr0_virt), as_start, as_end, code_address, code_size, system_resource, resource_limit));
/* Note that we've updated the table (since we created it). */
this->NoteUpdated();
R_SUCCEED();
}
Result KPageTable::Finalize() {
/* Only process tables should be finalized. */
MESOSPHERE_ASSERT(!this->IsKernel());
/* NOTE: Here Nintendo calls an unknown OnFinalize function. */
/* this->OnFinalize(); */
/* Note that we've updated (to ensure we're synchronized). */
this->NoteUpdated();
/* NOTE: Here Nintendo calls a second unknown OnFinalize function. */
/* this->OnFinalize2(); */
/* Free all pages in the table. */
{
/* Get implementation objects. */
auto &impl = this->GetImpl();
auto &mm = Kernel::GetMemoryManager();
/* Traverse, freeing all pages. */
{
/* Begin the traversal. */
TraversalContext context;
TraversalEntry entry;
KPhysicalAddress cur_phys_addr = Null<KPhysicalAddress>;
size_t cur_size = 0;
u8 has_attr = 0;
bool cur_valid = impl.BeginTraversal(std::addressof(entry), std::addressof(context), this->GetAddressSpaceStart());
while (true) {
if (cur_valid) {
/* Free the actual pages, if there are any. */
if (IsHeapPhysicalAddressForFinalize(entry.phys_addr)) {
if (cur_size > 0) {
/* NOTE: Nintendo really does check next_entry.attr == (cur_entry.attr != 0)...but attr is always zero as of 18.0.0, and this is "probably" for the new console or debug-only anyway, */
/* so we'll implement the weird logic verbatim even though it doesn't match the GetContiguousRange logic. */
if (entry.phys_addr == cur_phys_addr + cur_size && entry.attr == has_attr) {
/* Just extend the block, since we can. */
cur_size += entry.block_size;
} else {
/* Close the block, and begin tracking anew. */
mm.Close(cur_phys_addr, cur_size / PageSize);
cur_phys_addr = entry.phys_addr;
cur_size = entry.block_size;
has_attr = entry.attr != 0;
}
} else {
cur_phys_addr = entry.phys_addr;
cur_size = entry.block_size;
has_attr = entry.attr != 0;
}
}
/* Clean up the page table entries. */
bool freeing_table = false;
while (true) {
/* Clear the entries. */
const size_t num_to_clear = (!freeing_table && context.is_contiguous) ? BlocksPerContiguousBlock : 1;
auto *pte = reinterpret_cast<PageTableEntry *>(context.is_contiguous ? util::AlignDown(reinterpret_cast<uintptr_t>(context.level_entries[context.level]), BlocksPerContiguousBlock * sizeof(PageTableEntry)) : reinterpret_cast<uintptr_t>(context.level_entries[context.level]));
for (size_t i = 0; i < num_to_clear; ++i) {
pte[i] = InvalidPageTableEntry;
}
/* Remove the entries from the previous table. */
if (context.level != KPageTableImpl::EntryLevel_L1) {
context.level_entries[context.level + 1]->RemoveTableEntries(num_to_clear);
}
/* If we cleared a table, we need to note that we updated and free the table. */
if (freeing_table) {
KVirtualAddress table = KVirtualAddress(util::AlignDown(reinterpret_cast<uintptr_t>(context.level_entries[context.level - 1]), PageSize));
ClearPageTable(table);
this->GetPageTableManager().Free(table);
}
/* Advance; we're no longer contiguous. */
context.is_contiguous = false;
context.level_entries[context.level] = pte + num_to_clear - 1;
/* We may have removed the last entries in a table, in which case we can free and unmap the tables. */
if (context.level >= KPageTableImpl::EntryLevel_L1 || context.level_entries[context.level + 1]->GetTableNumEntries() != 0) {
break;
}
/* Advance; we will not be working with blocks any more. */
context.level = static_cast<KPageTableImpl::EntryLevel>(util::ToUnderlying(context.level) + 1);
freeing_table = true;
}
}
/* Continue the traversal. */
cur_valid = impl.ContinueTraversal(std::addressof(entry), std::addressof(context));
}
/* Free any remaining pages. */
if (cur_size > 0) {
mm.Close(cur_phys_addr, cur_size / PageSize);
}
}
/* Clear the L1 table. */
{
const KVirtualAddress l1_table = reinterpret_cast<uintptr_t>(impl.Finalize());
ClearPageTable(l1_table);
}
/* Perform inherited finalization. */
KPageTableBase::Finalize();
}
R_SUCCEED();
}
Result KPageTable::OperateImpl(PageLinkedList *page_list, KProcessAddress virt_addr, size_t num_pages, KPhysicalAddress phys_addr, bool is_pa_valid, const KPageProperties properties, OperationType operation, bool reuse_ll) {
/* Check validity of parameters. */
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
MESOSPHERE_ASSERT(num_pages > 0);
MESOSPHERE_ASSERT(util::IsAligned(GetInteger(virt_addr), PageSize));
MESOSPHERE_ASSERT(this->ContainsPages(virt_addr, num_pages));
if (operation == OperationType_Map) {
MESOSPHERE_ABORT_UNLESS(is_pa_valid);
MESOSPHERE_ASSERT(util::IsAligned(GetInteger(phys_addr), PageSize));
} else {
MESOSPHERE_ABORT_UNLESS(!is_pa_valid);
}
if (operation == OperationType_Unmap) {
R_RETURN(this->Unmap(virt_addr, num_pages, page_list, false, reuse_ll));
} else if (operation == OperationType_Separate) {
R_RETURN(this->SeparatePages(virt_addr, num_pages, page_list, reuse_ll));
} else {
auto entry_template = this->GetEntryTemplate(properties);
switch (operation) {
case OperationType_Map:
/* If mapping io or uncached pages, ensure that there is no pending reschedule. */
if (properties.io || properties.uncached) {
KScopedSchedulerLock sl;
}
R_RETURN(this->MapContiguous(virt_addr, phys_addr, num_pages, entry_template, properties.disable_merge_attributes == DisableMergeAttribute_DisableHead, page_list, reuse_ll));
case OperationType_ChangePermissions:
R_RETURN(this->ChangePermissions(virt_addr, num_pages, entry_template, properties.disable_merge_attributes, false, false, page_list, reuse_ll));
case OperationType_ChangePermissionsAndRefresh:
R_RETURN(this->ChangePermissions(virt_addr, num_pages, entry_template, properties.disable_merge_attributes, true, false, page_list, reuse_ll));
case OperationType_ChangePermissionsAndRefreshAndFlush:
R_RETURN(this->ChangePermissions(virt_addr, num_pages, entry_template, properties.disable_merge_attributes, true, true, page_list, reuse_ll));
MESOSPHERE_UNREACHABLE_DEFAULT_CASE();
}
}
}
Result KPageTable::OperateImpl(PageLinkedList *page_list, KProcessAddress virt_addr, size_t num_pages, const KPageGroup &page_group, const KPageProperties properties, OperationType operation, bool reuse_ll) {
/* Check validity of parameters. */
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
MESOSPHERE_ASSERT(util::IsAligned(GetInteger(virt_addr), PageSize));
MESOSPHERE_ASSERT(num_pages > 0);
MESOSPHERE_ASSERT(num_pages == page_group.GetNumPages());
/* Map the page group. */
auto entry_template = this->GetEntryTemplate(properties);
switch (operation) {
case OperationType_MapGroup:
case OperationType_MapFirstGroup:
/* If mapping io or uncached pages, ensure that there is no pending reschedule. */
if (properties.io || properties.uncached) {
KScopedSchedulerLock sl;
}
R_RETURN(this->MapGroup(virt_addr, page_group, num_pages, entry_template, properties.disable_merge_attributes == DisableMergeAttribute_DisableHead, operation != OperationType_MapFirstGroup, page_list, reuse_ll));
MESOSPHERE_UNREACHABLE_DEFAULT_CASE();
}
}
Result KPageTable::Unmap(KProcessAddress virt_addr, size_t num_pages, PageLinkedList *page_list, bool force, bool reuse_ll) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
/* Ensure there are no pending data writes. */
cpu::DataSynchronizationBarrier();
auto &impl = this->GetImpl();
/* If we're not forcing an unmap, separate pages immediately. */
if (!force) {
R_TRY(this->SeparatePages(virt_addr, num_pages, page_list, reuse_ll));
}
/* Cache initial addresses for use on cleanup. */
const KProcessAddress orig_virt_addr = virt_addr;
size_t remaining_pages = num_pages;
/* Ensure that any pages we track close on exit. */
KPageGroup pages_to_close(this->GetBlockInfoManager());
ON_SCOPE_EXIT { pages_to_close.CloseAndReset(); };
/* Begin traversal. */
TraversalContext context;
TraversalEntry next_entry;
bool next_valid = impl.BeginTraversal(std::addressof(next_entry), std::addressof(context), virt_addr);
while (remaining_pages > 0) {
/* Handle the case where we're not valid. */
if (!next_valid) {
MESOSPHERE_ABORT_UNLESS(force);
const size_t cur_size = std::min(next_entry.block_size - (GetInteger(virt_addr) & (next_entry.block_size - 1)), remaining_pages * PageSize);
remaining_pages -= cur_size / PageSize;
virt_addr += cur_size;
next_valid = impl.ContinueTraversal(std::addressof(next_entry), std::addressof(context));
continue;
}
/* Handle the case where the block is bigger than it should be. */
if (next_entry.block_size > remaining_pages * PageSize) {
MESOSPHERE_ABORT_UNLESS(force);
MESOSPHERE_R_ABORT_UNLESS(this->SeparatePagesImpl(std::addressof(next_entry), std::addressof(context), virt_addr, remaining_pages * PageSize, page_list, reuse_ll));
}
/* Check that our state is coherent. */
MESOSPHERE_ASSERT((next_entry.block_size / PageSize) <= remaining_pages);
MESOSPHERE_ASSERT(util::IsAligned(GetInteger(next_entry.phys_addr), next_entry.block_size));
/* Unmap the block. */
bool freeing_table = false;
while (true) {
/* Clear the entries. */
const size_t num_to_clear = (!freeing_table && context.is_contiguous) ? BlocksPerContiguousBlock : 1;
auto *pte = reinterpret_cast<PageTableEntry *>(context.is_contiguous ? util::AlignDown(reinterpret_cast<uintptr_t>(context.level_entries[context.level]), BlocksPerContiguousBlock * sizeof(PageTableEntry)) : reinterpret_cast<uintptr_t>(context.level_entries[context.level]));
for (size_t i = 0; i < num_to_clear; ++i) {
pte[i] = InvalidPageTableEntry;
}
/* Remove the entries from the previous table. */
if (context.level != KPageTableImpl::EntryLevel_L1) {
context.level_entries[context.level + 1]->RemoveTableEntries(num_to_clear);
}
/* If we cleared a table, we need to note that we updated and free the table. */
if (freeing_table) {
this->NoteUpdated();
this->FreePageTable(page_list, KVirtualAddress(util::AlignDown(reinterpret_cast<uintptr_t>(context.level_entries[context.level - 1]), PageSize)));
}
/* Advance; we're no longer contiguous. */
context.is_contiguous = false;
context.level_entries[context.level] = pte + num_to_clear - 1;
/* We may have removed the last entries in a table, in which case we can free and unmap the tables. */
if (context.level >= KPageTableImpl::EntryLevel_L1 || context.level_entries[context.level + 1]->GetTableNumEntries() != 0) {
break;
}
/* Advance; we will not be working with blocks any more. */
context.level = static_cast<KPageTableImpl::EntryLevel>(util::ToUnderlying(context.level) + 1);
freeing_table = true;
}
/* Close the blocks. */
if (!force && IsHeapPhysicalAddress(next_entry.phys_addr)) {
const size_t block_num_pages = next_entry.block_size / PageSize;
if (R_FAILED(pages_to_close.AddBlock(next_entry.phys_addr, block_num_pages))) {
this->NoteUpdated();
Kernel::GetMemoryManager().Close(next_entry.phys_addr, block_num_pages);
pages_to_close.CloseAndReset();
}
}
/* Advance. */
size_t freed_size = next_entry.block_size;
if (freeing_table) {
/* We advanced more than by the block, so we need to calculate the actual advanced size. */
const KProcessAddress new_virt_addr = util::AlignUp(GetInteger(virt_addr), impl.GetBlockSize(context.level, context.is_contiguous));
MESOSPHERE_ABORT_UNLESS(new_virt_addr >= virt_addr + next_entry.block_size);
freed_size = std::min<size_t>(new_virt_addr - virt_addr, remaining_pages * PageSize);
}
/* We can just advance by the block size. */
virt_addr += freed_size;
remaining_pages -= freed_size / PageSize;
next_valid = impl.ContinueTraversal(std::addressof(next_entry), std::addressof(context));
}
/* Ensure we remain coherent. */
if (this->IsKernel() && num_pages == 1) {
this->NoteSingleKernelPageUpdated(orig_virt_addr);
} else {
this->NoteUpdated();
}
R_SUCCEED();
}
Result KPageTable::Map(KProcessAddress virt_addr, KPhysicalAddress phys_addr, size_t num_pages, PageTableEntry entry_template, bool disable_head_merge, size_t page_size, PageLinkedList *page_list, bool reuse_ll) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
/* MESOSPHERE_ASSERT(util::IsAligned(GetInteger(virt_addr), PageSize)); */
/* MESOSPHERE_ASSERT(util::IsAligned(GetInteger(phys_addr), PageSize)); */
auto &impl = this->GetImpl();
u8 sw_reserved_bits = PageTableEntry::EncodeSoftwareReservedBits(disable_head_merge, false, false);
/* Begin traversal. */
TraversalContext context;
TraversalEntry entry;
bool valid = impl.BeginTraversal(std::addressof(entry), std::addressof(context), virt_addr);
/* Iterate, mapping each page. */
while (num_pages > 0) {
/* If we're mapping at the address, there must be nothing there. */
MESOSPHERE_ABORT_UNLESS(!valid);
/* If we fail, clean up any empty tables we may have allocated. */
ON_RESULT_FAILURE {
/* Remove entries for and free any tables. */
while (context.level < KPageTableImpl::EntryLevel_L1) {
/* If the higher-level table has entries, we don't need to do a free. */
if (context.level_entries[context.level + 1]->GetTableNumEntries() != 0) {
break;
}
/* If there's no table, we also don't need to do a free. */
const KVirtualAddress table = KVirtualAddress(util::AlignDown(reinterpret_cast<uintptr_t>(context.level_entries[context.level]), PageSize));
if (table == Null<KVirtualAddress>) {
break;
}
/* Clear the entry for the table we're removing. */
*context.level_entries[context.level + 1] = InvalidPageTableEntry;
/* Remove the entry for the table one level higher. */
if (context.level + 1 < KPageTableImpl::EntryLevel_L1) {
context.level_entries[context.level + 2]->RemoveTableEntries(1);
}
/* Advance our level. */
context.level = static_cast<KPageTableImpl::EntryLevel>(util::ToUnderlying(context.level) + 1);
/* Note that we performed an update and free the table. */
this->NoteUpdated();
this->FreePageTable(page_list, table);
}
};
/* If necessary, allocate page tables for the entry. */
size_t mapping_size = entry.block_size;
while (mapping_size > page_size) {
/* Allocate the table. */
const auto table = AllocatePageTable(page_list, reuse_ll);
R_UNLESS(table != Null<KVirtualAddress>, svc::ResultOutOfResource());
/* Wait for pending stores to complete. */
cpu::DataSynchronizationBarrierInnerShareableStore();
/* Update the block entry to be a table entry. */
*context.level_entries[context.level] = PageTableEntry(PageTableEntry::TableTag{}, KPageTable::GetPageTablePhysicalAddress(table), this->IsKernel(), true, 0);
/* Add the entry to the table containing this one. */
if (context.level != KPageTableImpl::EntryLevel_L1) {
context.level_entries[context.level + 1]->AddTableEntries(1);
}
/* Decrease our level. */
context.level = static_cast<KPageTableImpl::EntryLevel>(util::ToUnderlying(context.level) - 1);
/* Add our new entry to the context. */
context.level_entries[context.level] = GetPointer<PageTableEntry>(table) + impl.GetLevelIndex(virt_addr, context.level);
/* Update our mapping size. */
mapping_size = impl.GetBlockSize(context.level);
}
/* Determine how many pages we can set up on this iteration. */
const size_t block_size = impl.GetBlockSize(context.level);
const size_t max_ptes = (context.level == KPageTableImpl::EntryLevel_L1 ? impl.GetNumL1Entries() : BlocksPerTable) - ((reinterpret_cast<uintptr_t>(context.level_entries[context.level]) / sizeof(PageTableEntry)) & (BlocksPerTable - 1));
const size_t max_pages = (block_size * max_ptes) / PageSize;
const size_t cur_pages = std::min(max_pages, num_pages);
/* Determine the new base attribute. */
const bool contig = page_size >= BlocksPerContiguousBlock * mapping_size;
const size_t num_ptes = cur_pages / (block_size / PageSize);
auto *pte = context.level_entries[context.level];
for (size_t i = 0; i < num_ptes; ++i) {
*pte = PageTableEntry(PageTableEntry::BlockTag{}, phys_addr + i * block_size, entry_template, sw_reserved_bits, contig, context.level == KPageTableImpl::EntryLevel_L3);
sw_reserved_bits &= ~(PageTableEntry::SoftwareReservedBit_DisableMergeHead);
}
/* Add the entries to the table containing this one. */
if (context.level != KPageTableImpl::EntryLevel_L1) {
context.level_entries[context.level + 1]->AddTableEntries(num_ptes);
}
/* Update our context. */
context.is_contiguous = contig;
context.level_entries[context.level] = pte + num_ptes - (contig ? BlocksPerContiguousBlock : 1);
/* Advance our addresses. */
phys_addr += cur_pages * PageSize;
virt_addr += cur_pages * PageSize;
num_pages -= cur_pages;
/* Continue traversal. */
valid = impl.ContinueTraversal(std::addressof(entry), std::addressof(context));
}
/* We mapped, so wait for our writes to take. */
cpu::DataSynchronizationBarrierInnerShareableStore();
R_SUCCEED();
}
Result KPageTable::MapContiguous(KProcessAddress virt_addr, KPhysicalAddress phys_addr, size_t num_pages, PageTableEntry entry_template, bool disable_head_merge, PageLinkedList *page_list, bool reuse_ll) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
/* Cache initial addresses for use on cleanup. */
const KProcessAddress orig_virt_addr = virt_addr;
const KPhysicalAddress orig_phys_addr = phys_addr;
size_t remaining_pages = num_pages;
/* Map the pages, using a guard to ensure we don't leak. */
{
ON_RESULT_FAILURE { MESOSPHERE_R_ABORT_UNLESS(this->Unmap(orig_virt_addr, num_pages, page_list, true, true)); };
if (num_pages < ContiguousPageSize / PageSize) {
R_TRY(this->Map(virt_addr, phys_addr, num_pages, entry_template, disable_head_merge && virt_addr == orig_virt_addr, L3BlockSize, page_list, reuse_ll));
remaining_pages -= num_pages;
virt_addr += num_pages * PageSize;
phys_addr += num_pages * PageSize;
} else {
/* Map the fractional part of the pages. */
size_t alignment;
for (alignment = ContiguousPageSize; (virt_addr & (alignment - 1)) == (phys_addr & (alignment - 1)); alignment = GetLargerAlignment(alignment)) {
/* Check if this would be our last map. */
const size_t pages_to_map = ((alignment - (virt_addr & (alignment - 1))) & (alignment - 1)) / PageSize;
if (pages_to_map + (alignment / PageSize) > remaining_pages) {
break;
}
/* Map pages, if we should. */
if (pages_to_map > 0) {
R_TRY(this->Map(virt_addr, phys_addr, pages_to_map, entry_template, disable_head_merge && virt_addr == orig_virt_addr, GetSmallerAlignment(alignment), page_list, reuse_ll));
remaining_pages -= pages_to_map;
virt_addr += pages_to_map * PageSize;
phys_addr += pages_to_map * PageSize;
}
/* Don't go further than L1 block. */
if (alignment == L1BlockSize) {
break;
}
}
while (remaining_pages > 0) {
/* Select the next smallest alignment. */
alignment = GetSmallerAlignment(alignment);
MESOSPHERE_ASSERT((virt_addr & (alignment - 1)) == 0);
MESOSPHERE_ASSERT((phys_addr & (alignment - 1)) == 0);
/* Map pages, if we should. */
const size_t pages_to_map = util::AlignDown(remaining_pages, alignment / PageSize);
if (pages_to_map > 0) {
R_TRY(this->Map(virt_addr, phys_addr, pages_to_map, entry_template, disable_head_merge && virt_addr == orig_virt_addr, alignment, page_list, reuse_ll));
remaining_pages -= pages_to_map;
virt_addr += pages_to_map * PageSize;
phys_addr += pages_to_map * PageSize;
}
}
}
}
/* Perform what coalescing we can. */
this->MergePages(orig_virt_addr, num_pages, page_list);
/* Open references to the pages, if we should. */
if (IsHeapPhysicalAddress(orig_phys_addr)) {
Kernel::GetMemoryManager().Open(orig_phys_addr, num_pages);
}
R_SUCCEED();
}
Result KPageTable::MapGroup(KProcessAddress virt_addr, const KPageGroup &pg, size_t num_pages, PageTableEntry entry_template, bool disable_head_merge, bool not_first, PageLinkedList *page_list, bool reuse_ll) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
/* We want to maintain a new reference to every page in the group. */
KScopedPageGroup spg(pg, not_first);
/* Cache initial address for use on cleanup. */
const KProcessAddress orig_virt_addr = virt_addr;
size_t mapped_pages = 0;
/* Map the pages, using a guard to ensure we don't leak. */
{
ON_RESULT_FAILURE { MESOSPHERE_R_ABORT_UNLESS(this->Unmap(orig_virt_addr, num_pages, page_list, true, true)); };
if (num_pages < ContiguousPageSize / PageSize) {
for (const auto &block : pg) {
const KPhysicalAddress block_phys_addr = block.GetAddress();
const size_t cur_pages = block.GetNumPages();
R_TRY(this->Map(virt_addr, block_phys_addr, cur_pages, entry_template, disable_head_merge && virt_addr == orig_virt_addr, L3BlockSize, page_list, reuse_ll));
virt_addr += cur_pages * PageSize;
mapped_pages += cur_pages;
}
} else {
/* Create a block representing our virtual space. */
AlignedMemoryBlock virt_block(GetInteger(virt_addr), num_pages, L1BlockSize);
for (const auto &block : pg) {
/* Create a block representing this physical group, synchronize its alignment to our virtual block. */
const KPhysicalAddress block_phys_addr = block.GetAddress();
size_t cur_pages = block.GetNumPages();
AlignedMemoryBlock phys_block(GetInteger(block_phys_addr), cur_pages, virt_block.GetAlignment());
virt_block.SetAlignment(phys_block.GetAlignment());
while (cur_pages > 0) {
/* Find a physical region for us to map at. */
uintptr_t phys_choice = 0;
size_t phys_pages = 0;
phys_block.FindBlock(phys_choice, phys_pages);
/* If we didn't find a region, try decreasing our alignment. */
if (phys_pages == 0) {
const size_t next_alignment = KPageTable::GetSmallerAlignment(phys_block.GetAlignment());
MESOSPHERE_ASSERT(next_alignment >= PageSize);
phys_block.SetAlignment(next_alignment);
virt_block.SetAlignment(next_alignment);
continue;
}
/* Begin choosing virtual blocks to map at the region we chose. */
while (phys_pages > 0) {
/* Find a virtual region for us to map at. */
uintptr_t virt_choice = 0;
size_t virt_pages = phys_pages;
virt_block.FindBlock(virt_choice, virt_pages);
/* If we didn't find a region, try decreasing our alignment. */
if (virt_pages == 0) {
const size_t next_alignment = KPageTable::GetSmallerAlignment(virt_block.GetAlignment());
MESOSPHERE_ASSERT(next_alignment >= PageSize);
phys_block.SetAlignment(next_alignment);
virt_block.SetAlignment(next_alignment);
continue;
}
/* Map! */
R_TRY(this->Map(virt_choice, phys_choice, virt_pages, entry_template, disable_head_merge && virt_addr == orig_virt_addr, virt_block.GetAlignment(), page_list, reuse_ll));
/* Advance. */
phys_choice += virt_pages * PageSize;
phys_pages -= virt_pages;
cur_pages -= virt_pages;
mapped_pages += virt_pages;
}
}
}
}
}
MESOSPHERE_ASSERT(mapped_pages == num_pages);
/* Perform what coalescing we can. */
this->MergePages(orig_virt_addr, num_pages, page_list);
/* We succeeded! We want to persist the reference to the pages. */
spg.CancelClose();
R_SUCCEED();
}
bool KPageTable::MergePages(TraversalContext *context, PageLinkedList *page_list) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
auto &impl = this->GetImpl();
/* Iteratively merge, until we can't. */
bool merged = false;
while (true) {
/* Try to merge. */
KVirtualAddress freed_table = Null<KVirtualAddress>;
if (!impl.MergePages(std::addressof(freed_table), context)) {
break;
}
/* Note that we updated. */
this->NoteUpdated();
/* Free the page. */
if (freed_table != Null<KVirtualAddress>) {
ClearPageTable(freed_table);
this->FreePageTable(page_list, freed_table);
}
/* We performed at least one merge. */
merged = true;
}
return merged;
}
void KPageTable::MergePages(KProcessAddress virt_addr, size_t num_pages, PageLinkedList *page_list) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
auto &impl = this->GetImpl();
/* Begin traversal. */
TraversalContext context;
TraversalEntry entry;
MESOSPHERE_ABORT_UNLESS(impl.BeginTraversal(std::addressof(entry), std::addressof(context), virt_addr));
/* Merge start of the range. */
this->MergePages(std::addressof(context), page_list);
/* If we have more than one page, do the same for the end of the range. */
if (num_pages > 1) {
/* Begin traversal for end of range. */
const size_t size = num_pages * PageSize;
const auto end_page = virt_addr + size;
const auto last_page = end_page - PageSize;
MESOSPHERE_ABORT_UNLESS(impl.BeginTraversal(std::addressof(entry), std::addressof(context), last_page));
/* Merge. */
this->MergePages(std::addressof(context), page_list);
}
}
Result KPageTable::SeparatePagesImpl(TraversalEntry *entry, TraversalContext *context, KProcessAddress virt_addr, size_t block_size, PageLinkedList *page_list, bool reuse_ll) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
auto &impl = this->GetImpl();
/* If at any point we fail, we want to merge. */
ON_RESULT_FAILURE { this->MergePages(context, page_list); };
/* Iterate, separating until our block size is small enough. */
while (entry->block_size > block_size) {
/* If necessary, allocate a table. */
KVirtualAddress table = Null<KVirtualAddress>;
if (!context->is_contiguous) {
table = this->AllocatePageTable(page_list, reuse_ll);
R_UNLESS(table != Null<KVirtualAddress>, svc::ResultOutOfResource());
}
/* Separate. */
impl.SeparatePages(entry, context, virt_addr, nullptr);
this->NoteUpdated();
}
R_SUCCEED();
}
Result KPageTable::SeparatePages(KProcessAddress virt_addr, size_t num_pages, PageLinkedList *page_list, bool reuse_ll) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
auto &impl = this->GetImpl();
/* Begin traversal. */
TraversalContext start_context;
TraversalEntry entry;
MESOSPHERE_ABORT_UNLESS(impl.BeginTraversal(std::addressof(entry), std::addressof(start_context), virt_addr));
/* Separate pages at the start of the range. */
const size_t size = num_pages * PageSize;
R_TRY(this->SeparatePagesImpl(std::addressof(entry), std::addressof(start_context), virt_addr, std::min(util::GetAlignment(GetInteger(virt_addr)), size), page_list, reuse_ll));
/* If necessary, separate pages at the end of the range. */
if (num_pages > 1) {
const auto end_page = virt_addr + size;
const auto last_page = end_page - PageSize;
/* Begin traversal. */
TraversalContext end_context;
MESOSPHERE_ABORT_UNLESS(impl.BeginTraversal(std::addressof(entry), std::addressof(end_context), last_page));
ON_RESULT_FAILURE { this->MergePages(std::addressof(start_context), page_list); };
R_TRY(this->SeparatePagesImpl(std::addressof(entry), std::addressof(end_context), last_page, std::min(util::GetAlignment(GetInteger(end_page)), size), page_list, reuse_ll));
}
R_SUCCEED();
}
Result KPageTable::ChangePermissions(KProcessAddress virt_addr, size_t num_pages, PageTableEntry entry_template, DisableMergeAttribute disable_merge_attr, bool refresh_mapping, bool flush_mapping, PageLinkedList *page_list, bool reuse_ll) {
MESOSPHERE_ASSERT(this->IsLockedByCurrentThread());
/* Ensure there are no pending data writes. */
cpu::DataSynchronizationBarrier();
/* Separate pages before we change permissions. */
R_TRY(this->SeparatePages(virt_addr, num_pages, page_list, reuse_ll));
/* ===================================================== */
/* Define a helper function which will apply our template to entries. */
enum ApplyOption : u32 {
ApplyOption_None = 0,
ApplyOption_FlushDataCache = (1u << 0),
ApplyOption_MergeMappings = (1u << 1),
};
auto ApplyEntryTemplate = [this, virt_addr, disable_merge_attr, num_pages, page_list](PageTableEntry entry_template, u32 apply_option) -> void {
/* Create work variables for us to use. */
const KProcessAddress orig_virt_addr = virt_addr;
const KProcessAddress end_virt_addr = orig_virt_addr + (num_pages * PageSize);
KProcessAddress cur_virt_addr = virt_addr;
size_t remaining_pages = num_pages;
auto &impl = this->GetImpl();
/* Parse the disable merge attrs. */
const bool attr_disable_head = (disable_merge_attr & DisableMergeAttribute_DisableHead) != 0;
const bool attr_disable_head_body = (disable_merge_attr & DisableMergeAttribute_DisableHeadAndBody) != 0;
const bool attr_enable_head_body = (disable_merge_attr & DisableMergeAttribute_EnableHeadAndBody) != 0;
const bool attr_disable_tail = (disable_merge_attr & DisableMergeAttribute_DisableTail) != 0;
const bool attr_enable_tail = (disable_merge_attr & DisableMergeAttribute_EnableTail) != 0;
const bool attr_enable_and_merge = (disable_merge_attr & DisableMergeAttribute_EnableAndMergeHeadBodyTail) != 0;
/* Begin traversal. */
TraversalContext context;
TraversalEntry next_entry;
MESOSPHERE_ABORT_UNLESS(impl.BeginTraversal(std::addressof(next_entry), std::addressof(context), cur_virt_addr));
/* Continue changing properties until we've changed them for all pages. */
bool cleared_disable_merge_bits = false;
while (remaining_pages > 0) {
MESOSPHERE_ABORT_UNLESS(util::IsAligned(GetInteger(next_entry.phys_addr), next_entry.block_size));
MESOSPHERE_ABORT_UNLESS(next_entry.block_size <= remaining_pages * PageSize);
/* Determine if we're at the start. */
const bool is_start = (cur_virt_addr == orig_virt_addr);
const bool is_end = ((cur_virt_addr + next_entry.block_size) == end_virt_addr);
/* Determine the relevant merge attributes. */
bool disable_head_merge, disable_head_body_merge, disable_tail_merge;
if (next_entry.IsHeadMergeDisabled()) {
disable_head_merge = true;
} else if (attr_disable_head) {
disable_head_merge = is_start;
} else {
disable_head_merge = false;
}
if (is_start) {
if (attr_disable_head_body) {
disable_head_body_merge = true;
} else if (attr_enable_head_body) {
disable_head_body_merge = false;
} else {
disable_head_body_merge = (!attr_enable_and_merge && next_entry.IsHeadAndBodyMergeDisabled());
}
} else {
disable_head_body_merge = (!attr_enable_and_merge && next_entry.IsHeadAndBodyMergeDisabled());
cleared_disable_merge_bits |= (attr_enable_and_merge && next_entry.IsHeadAndBodyMergeDisabled());
}
if (is_end) {
if (attr_disable_tail) {
disable_tail_merge = true;
} else if (attr_enable_tail) {
disable_tail_merge = false;
} else {
disable_tail_merge = (!attr_enable_and_merge && next_entry.IsTailMergeDisabled());
}
} else {
disable_tail_merge = (!attr_enable_and_merge && next_entry.IsTailMergeDisabled());
cleared_disable_merge_bits |= (attr_enable_and_merge && next_entry.IsTailMergeDisabled());
}
/* Encode the merge disable flags into the software reserved bits. */
u8 sw_reserved_bits = PageTableEntry::EncodeSoftwareReservedBits(disable_head_merge, disable_head_body_merge, disable_tail_merge);
/* If we should flush entries, do so. */
if ((apply_option & ApplyOption_FlushDataCache) != 0) {
if (IsHeapPhysicalAddress(next_entry.phys_addr)) {
cpu::FlushDataCache(GetVoidPointer(GetHeapVirtualAddress(next_entry.phys_addr)), next_entry.block_size);
}
}
/* Apply the entry template. */
{
const size_t num_entries = context.is_contiguous ? BlocksPerContiguousBlock : 1;
auto * const pte = context.level_entries[context.level];
const size_t block_size = impl.GetBlockSize(context.level);
for (size_t i = 0; i < num_entries; ++i) {
pte[i] = PageTableEntry(PageTableEntry::BlockTag{}, next_entry.phys_addr + i * block_size, entry_template, sw_reserved_bits, context.is_contiguous, context.level == KPageTableImpl::EntryLevel_L3);
sw_reserved_bits &= ~(PageTableEntry::SoftwareReservedBit_DisableMergeHead);
}
}
/* If our option asks us to, try to merge mappings. */
bool merge = ((apply_option & ApplyOption_MergeMappings) != 0 || cleared_disable_merge_bits) && next_entry.block_size < L1BlockSize;
if (merge) {
const size_t larger_align = GetLargerAlignment(next_entry.block_size);
if (util::IsAligned(GetInteger(cur_virt_addr) + next_entry.block_size, larger_align)) {
const uintptr_t aligned_start = util::AlignDown(GetInteger(cur_virt_addr), larger_align);
if (orig_virt_addr <= aligned_start && aligned_start + larger_align - 1 < GetInteger(orig_virt_addr) + (num_pages * PageSize) - 1) {
merge = this->MergePages(std::addressof(context), page_list);
} else {
merge = false;
}
} else {
merge = false;
}
}
/* If we merged, correct the traversal to a sane state. */
if (merge) {
/* NOTE: Begin a new traversal, now that we've merged. */
MESOSPHERE_ABORT_UNLESS(impl.BeginTraversal(std::addressof(next_entry), std::addressof(context), cur_virt_addr));
/* The actual size needs to not take into account the portion of the block before our virtual address. */
const size_t actual_size = next_entry.block_size - (GetInteger(next_entry.phys_addr) & (next_entry.block_size - 1));
remaining_pages -= std::min(remaining_pages, actual_size / PageSize);
cur_virt_addr += actual_size;
} else {
/* If we didn't merge, just advance. */
remaining_pages -= next_entry.block_size / PageSize;
cur_virt_addr += next_entry.block_size;
}
/* Continue our traversal. */
if (remaining_pages == 0) {
break;
}
MESOSPHERE_ABORT_UNLESS(impl.ContinueTraversal(std::addressof(next_entry), std::addressof(context)));
}
};
/* ===================================================== */
/* If we don't need to refresh the pages, we can just apply the mappings. */
if (!refresh_mapping) {
ApplyEntryTemplate(entry_template, ApplyOption_None);
this->NoteUpdated();
} else {
/* We need to refresh the mappings. */
/* First, apply the changes without the mapped bit. This will cause all entries to page fault if accessed. */
{
PageTableEntry unmapped_template = entry_template;
unmapped_template.SetMapped(false);
ApplyEntryTemplate(unmapped_template, ApplyOption_MergeMappings);
this->NoteUpdated();
}
/* Next, take and immediately release the scheduler lock. This will force a reschedule. */
{
KScopedSchedulerLock sl;
}
/* Finally, apply the changes as directed, flushing the mappings before they're applied (if we should). */
ApplyEntryTemplate(entry_template, flush_mapping ? ApplyOption_FlushDataCache : ApplyOption_None);
}
/* We've succeeded, now perform what coalescing we can. */
this->MergePages(virt_addr, num_pages, page_list);
R_SUCCEED();
}
void KPageTable::FinalizeUpdateImpl(PageLinkedList *page_list) {
while (page_list->Peek()) {
KVirtualAddress page = KVirtualAddress(page_list->Pop());
MESOSPHERE_ASSERT(this->GetPageTableManager().IsInPageTableHeap(page));
MESOSPHERE_ASSERT(this->GetPageTableManager().GetRefCount(page) == 0);
this->GetPageTableManager().Free(page);
}
}
}