Kernel: Wrap RegionTree objects in SpinlockProtected

This makes locking them much more straightforward, and we can remove
a bunch of confusing use of AddressSpace::m_lock. That lock will also
be converted to use of SpinlockProtected in a subsequent patch.

1 files changed, 80 insertions, 72 deletions

diff --git a/Kernel/Coredump.cpp b/Kernel/Coredump.cpp
index 1348f232f8..1c7f3add12 100644
--- a/Kernel/Coredump.cpp
+++ b/Kernel/Coredump.cpp
@@ -46,16 +46,18 @@ Coredump::Coredump(NonnullLockRefPtr<Process> process, NonnullLockRefPtr<OpenFil
     , m_description(move(description))
 {
     m_num_program_headers = 0;
-    for ([[maybe_unused]] auto& region : m_process->address_space().regions()) {
+    m_process->address_space().region_tree().with([&](auto& region_tree) {
+        for (auto& region : region_tree.regions()) {
 #if !INCLUDE_USERSPACE_HEAP_MEMORY_IN_COREDUMPS
-        if (looks_like_userspace_heap_region(region))
-            continue;
+            if (looks_like_userspace_heap_region(region))
+                continue;
 #endif
 
-        if (region.access() == Memory::Region::Access::None)
-            continue;
-        ++m_num_program_headers;
-    }
+            if (region.access() == Memory::Region::Access::None)
+                continue;
+            ++m_num_program_headers;
+        }
+    });
     ++m_num_program_headers; // +1 for NOTE segment
 }
 
@@ -133,37 +135,39 @@ ErrorOr<void> Coredump::write_elf_header()
 ErrorOr<void> Coredump::write_program_headers(size_t notes_size)
 {
     size_t offset = sizeof(ElfW(Ehdr)) + m_num_program_headers * sizeof(ElfW(Phdr));
-    for (auto& region : m_process->address_space().regions()) {
+    m_process->address_space().region_tree().with([&](auto& region_tree) {
+        for (auto& region : region_tree.regions()) {
 
 #if !INCLUDE_USERSPACE_HEAP_MEMORY_IN_COREDUMPS
-        if (looks_like_userspace_heap_region(region))
-            continue;
+            if (looks_like_userspace_heap_region(region))
+                continue;
 #endif
 
-        if (region.access() == Memory::Region::Access::None)
-            continue;
+            if (region.access() == Memory::Region::Access::None)
+                continue;
 
-        ElfW(Phdr) phdr {};
+            ElfW(Phdr) phdr {};
 
-        phdr.p_type = PT_LOAD;
-        phdr.p_offset = offset;
-        phdr.p_vaddr = region.vaddr().get();
-        phdr.p_paddr = 0;
+            phdr.p_type = PT_LOAD;
+            phdr.p_offset = offset;
+            phdr.p_vaddr = region.vaddr().get();
+            phdr.p_paddr = 0;
 
-        phdr.p_filesz = region.page_count() * PAGE_SIZE;
-        phdr.p_memsz = region.page_count() * PAGE_SIZE;
-        phdr.p_align = 0;
+            phdr.p_filesz = region.page_count() * PAGE_SIZE;
+            phdr.p_memsz = region.page_count() * PAGE_SIZE;
+            phdr.p_align = 0;
 
-        phdr.p_flags = region.is_readable() ? PF_R : 0;
-        if (region.is_writable())
-            phdr.p_flags |= PF_W;
-        if (region.is_executable())
-            phdr.p_flags |= PF_X;
+            phdr.p_flags = region.is_readable() ? PF_R : 0;
+            if (region.is_writable())
+                phdr.p_flags |= PF_W;
+            if (region.is_executable())
+                phdr.p_flags |= PF_X;
 
-        offset += phdr.p_filesz;
+            offset += phdr.p_filesz;
 
-        [[maybe_unused]] auto rc = m_description->write(UserOrKernelBuffer::for_kernel_buffer(reinterpret_cast<uint8_t*>(&phdr)), sizeof(ElfW(Phdr)));
-    }
+            [[maybe_unused]] auto rc = m_description->write(UserOrKernelBuffer::for_kernel_buffer(reinterpret_cast<uint8_t*>(&phdr)), sizeof(ElfW(Phdr)));
+        }
+    });
 
     ElfW(Phdr) notes_pheader {};
     notes_pheader.p_type = PT_NOTE;
@@ -184,36 +188,38 @@ ErrorOr<void> Coredump::write_regions()
 {
     u8 zero_buffer[PAGE_SIZE] = {};
 
-    for (auto& region : m_process->address_space().regions()) {
-        VERIFY(!region.is_kernel());
+    return m_process->address_space().region_tree().with([&](auto& region_tree) -> ErrorOr<void> {
+        for (auto& region : region_tree.regions()) {
+            VERIFY(!region.is_kernel());
 
 #if !INCLUDE_USERSPACE_HEAP_MEMORY_IN_COREDUMPS
-        if (looks_like_userspace_heap_region(region))
-            continue;
+            if (looks_like_userspace_heap_region(region))
+                continue;
 #endif
 
-        if (region.access() == Memory::Region::Access::None)
-            continue;
-
-        // If we crashed in the middle of mapping in Regions, they do not have a page directory yet, and will crash on a remap() call
-        if (!region.is_mapped())
-            continue;
-
-        region.set_readable(true);
-        region.remap();
-
-        for (size_t i = 0; i < region.page_count(); i++) {
-            auto page = region.physical_page(i);
-            auto src_buffer = [&]() -> ErrorOr<UserOrKernelBuffer> {
-                if (page)
-                    return UserOrKernelBuffer::for_user_buffer(reinterpret_cast<uint8_t*>((region.vaddr().as_ptr() + (i * PAGE_SIZE))), PAGE_SIZE);
-                // If the current page is not backed by a physical page, we zero it in the coredump file.
-                return UserOrKernelBuffer::for_kernel_buffer(zero_buffer);
-            }();
-            TRY(m_description->write(src_buffer.value(), PAGE_SIZE));
+            if (region.access() == Memory::Region::Access::None)
+                continue;
+
+            // If we crashed in the middle of mapping in Regions, they do not have a page directory yet, and will crash on a remap() call
+            if (!region.is_mapped())
+                continue;
+
+            region.set_readable(true);
+            region.remap();
+
+            for (size_t i = 0; i < region.page_count(); i++) {
+                auto page = region.physical_page(i);
+                auto src_buffer = [&]() -> ErrorOr<UserOrKernelBuffer> {
+                    if (page)
+                        return UserOrKernelBuffer::for_user_buffer(reinterpret_cast<uint8_t*>((region.vaddr().as_ptr() + (i * PAGE_SIZE))), PAGE_SIZE);
+                    // If the current page is not backed by a physical page, we zero it in the coredump file.
+                    return UserOrKernelBuffer::for_kernel_buffer(zero_buffer);
+                }();
+                TRY(m_description->write(src_buffer.value(), PAGE_SIZE));
+            }
         }
-    }
-    return {};
+        return {};
+    });
 }
 
 ErrorOr<void> Coredump::write_notes_segment(ReadonlyBytes notes_segment)
@@ -273,33 +279,35 @@ ErrorOr<void> Coredump::create_notes_threads_data(auto& builder) const
 ErrorOr<void> Coredump::create_notes_regions_data(auto& builder) const
 {
     size_t region_index = 0;
-    for (auto const& region : m_process->address_space().regions()) {
+    return m_process->address_space().region_tree().with([&](auto& region_tree) -> ErrorOr<void> {
+        for (auto const& region : region_tree.regions()) {
 
 #if !INCLUDE_USERSPACE_HEAP_MEMORY_IN_COREDUMPS
-        if (looks_like_userspace_heap_region(region))
-            continue;
+            if (looks_like_userspace_heap_region(region))
+                continue;
 #endif
 
-        if (region.access() == Memory::Region::Access::None)
-            continue;
+            if (region.access() == Memory::Region::Access::None)
+                continue;
 
-        ELF::Core::MemoryRegionInfo info {};
-        info.header.type = ELF::Core::NotesEntryHeader::Type::MemoryRegionInfo;
+            ELF::Core::MemoryRegionInfo info {};
+            info.header.type = ELF::Core::NotesEntryHeader::Type::MemoryRegionInfo;
 
-        info.region_start = region.vaddr().get();
-        info.region_end = region.vaddr().offset(region.size()).get();
-        info.program_header_index = region_index++;
+            info.region_start = region.vaddr().get();
+            info.region_end = region.vaddr().offset(region.size()).get();
+            info.program_header_index = region_index++;
 
-        TRY(builder.append_bytes(ReadonlyBytes { (void*)&info, sizeof(info) }));
+            TRY(builder.append_bytes(ReadonlyBytes { (void*)&info, sizeof(info) }));
 
-        // NOTE: The region name *is* null-terminated, so the following is ok:
-        auto name = region.name();
-        if (name.is_empty())
-            TRY(builder.append('\0'));
-        else
-            TRY(builder.append(name.characters_without_null_termination(), name.length() + 1));
-    }
-    return {};
+            // NOTE: The region name *is* null-terminated, so the following is ok:
+            auto name = region.name();
+            if (name.is_empty())
+                TRY(builder.append('\0'));
+            else
+                TRY(builder.append(name.characters_without_null_termination(), name.length() + 1));
+        }
+        return {};
+    });
 }
 
 ErrorOr<void> Coredump::create_notes_metadata_data(auto& builder) const