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#pragma once
#include <AK/AKString.h>
#include <AK/Bitmap.h>
#include <Kernel/VM/PageDirectory.h>
#include <Kernel/VM/RangeAllocator.h>
class Inode;
class VMObject;
class Region : public RefCounted<Region> {
friend class MemoryManager;
public:
enum Access {
Read = 1,
Write = 2,
Execute = 4,
};
static NonnullRefPtr<Region> create_user_accessible(const Range&, const StringView& name, u8 access, bool cow = false);
static NonnullRefPtr<Region> create_user_accessible(const Range&, NonnullRefPtr<VMObject>, size_t offset_in_vmobject, const StringView& name, u8 access, bool cow = false);
static NonnullRefPtr<Region> create_user_accessible(const Range&, NonnullRefPtr<Inode>, const StringView& name, u8 access, bool cow = false);
static NonnullRefPtr<Region> create_kernel_only(const Range&, const StringView& name, u8 access, bool cow = false);
~Region();
VirtualAddress vaddr() const { return m_range.base(); }
size_t size() const { return m_range.size(); }
bool is_readable() const { return m_access & Access::Read; }
bool is_writable() const { return m_access & Access::Write; }
bool is_executable() const { return m_access & Access::Execute; }
const String& name() const { return m_name; }
void set_name(const String& name) { m_name = name; }
const VMObject& vmo() const { return *m_vmo; }
VMObject& vmo() { return *m_vmo; }
bool is_shared() const { return m_shared; }
void set_shared(bool shared) { m_shared = shared; }
bool is_user_accessible() const { return m_user_accessible; }
NonnullRefPtr<Region> clone();
bool contains(VirtualAddress vaddr) const
{
return m_range.contains(vaddr);
}
unsigned page_index_from_address(VirtualAddress vaddr) const
{
return (vaddr - m_range.base()).get() / PAGE_SIZE;
}
size_t first_page_index() const
{
return m_offset_in_vmo / PAGE_SIZE;
}
size_t last_page_index() const
{
return (first_page_index() + page_count()) - 1;
}
size_t page_count() const
{
return size() / PAGE_SIZE;
}
bool page_in();
int commit();
size_t amount_resident() const;
size_t amount_shared() const;
PageDirectory* page_directory() { return m_page_directory.ptr(); }
void set_page_directory(PageDirectory& page_directory)
{
ASSERT(!m_page_directory || m_page_directory == &page_directory);
m_page_directory = page_directory;
}
void release_page_directory()
{
ASSERT(m_page_directory);
m_page_directory.clear();
}
bool should_cow(size_t page_index) const { return m_cow_map.get(page_index); }
void set_should_cow(size_t page_index, bool cow) { m_cow_map.set(page_index, cow); }
void set_writable(bool b)
{
if (b)
m_access |= Access::Read;
else
m_access &= ~Access::Write;
}
private:
Region(const Range&, const String&, u8 access, bool cow = false);
Region(const Range&, NonnullRefPtr<VMObject>, size_t offset_in_vmo, const String&, u8 access, bool cow = false);
Region(const Range&, RefPtr<Inode>&&, const String&, u8 access, bool cow = false);
RefPtr<PageDirectory> m_page_directory;
Range m_range;
size_t m_offset_in_vmo { 0 };
NonnullRefPtr<VMObject> m_vmo;
String m_name;
u8 m_access { 0 };
bool m_shared { false };
bool m_user_accessible { false };
Bitmap m_cow_map;
};
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