LibGfx: Remove "purgeable Gfx::Bitmap" as a separate concept

This was a really weird thing to begin with, purgeable bitmaps were
basically regular bitmaps without a physical memory reservation.

Since all the clients of this code ended up populating the bitmaps
with pixels immediately after allocating them anyway, there was no
need to avoid the reservation.

Instead, all Gfx::Bitmaps are now purgeable, in the sense that they
can be marked as volatile or non-volatile.

The only difference here is that allocation failure is surfaced when
we try to create the bitmap instead of during the handling of a
subsequent page fault.

Userland/Libraries/LibGfx/BMPLoader.cpp

@@ -1185,7 +1185,7 @@ static bool decode_bmp_pixel_data(BMPLoadingContext& context)
 
     const u32 width = abs(context.dib.core.width);
     const u32 height = abs(context.dib.core.height);
-    context.bitmap = Bitmap::try_create_purgeable(format, { static_cast<int>(width), static_cast<int>(height) });
+    context.bitmap = Bitmap::try_create(format, { static_cast<int>(width), static_cast<int>(height) });
     if (!context.bitmap) {
         dbgln("BMP appears to have overly large dimensions");
         return false;

Userland/Libraries/LibGfx/Bitmap.cpp

@@ -67,18 +67,10 @@ static bool size_would_overflow(BitmapFormat format, const IntSize& size, int sc
 
 RefPtr<Bitmap> Bitmap::try_create(BitmapFormat format, const IntSize& size, int scale_factor)
 {
-    auto backing_store = Bitmap::try_allocate_backing_store(format, size, scale_factor, Purgeable::No);
+    auto backing_store = Bitmap::try_allocate_backing_store(format, size, scale_factor);
     if (!backing_store.has_value())
         return nullptr;
-    return adopt_ref(*new Bitmap(format, size, scale_factor, Purgeable::No, backing_store.value()));
+    return adopt_ref(*new Bitmap(format, size, scale_factor, backing_store.value()));
-}
-
-RefPtr<Bitmap> Bitmap::try_create_purgeable(BitmapFormat format, const IntSize& size, int scale_factor)
-{
-    auto backing_store = Bitmap::try_allocate_backing_store(format, size, scale_factor, Purgeable::Yes);
-    if (!backing_store.has_value())
-        return nullptr;
-    return adopt_ref(*new Bitmap(format, size, scale_factor, Purgeable::Yes, backing_store.value()));
 }
 
 RefPtr<Bitmap> Bitmap::try_create_shareable(BitmapFormat format, const IntSize& size, int scale_factor)
@@ -95,13 +87,12 @@ RefPtr<Bitmap> Bitmap::try_create_shareable(BitmapFormat format, const IntSize&
     return Bitmap::try_create_with_anonymous_buffer(format, buffer, size, scale_factor, {});
 }
 
-Bitmap::Bitmap(BitmapFormat format, const IntSize& size, int scale_factor, Purgeable purgeable, const BackingStore& backing_store)
+Bitmap::Bitmap(BitmapFormat format, const IntSize& size, int scale_factor, const BackingStore& backing_store)
     : m_size(size)
     , m_scale(scale_factor)
     , m_data(backing_store.data)
     , m_pitch(backing_store.pitch)
     , m_format(format)
-    , m_purgeable(purgeable == Purgeable::Yes)
 {
     VERIFY(!m_size.is_empty());
     VERIFY(!size_would_overflow(format, size, scale_factor));
@@ -289,7 +280,6 @@ Bitmap::Bitmap(BitmapFormat format, Core::AnonymousBuffer buffer, const IntSize&
     , m_data(buffer.data<void>())
     , m_pitch(minimum_pitch(size.width() * scale_factor, format))
     , m_format(format)
-    , m_purgeable(true)
     , m_buffer(move(buffer))
 {
     VERIFY(!is_indexed() || !palette.is_empty());
@@ -301,16 +291,10 @@ Bitmap::Bitmap(BitmapFormat format, Core::AnonymousBuffer buffer, const IntSize&
 
 RefPtr<Gfx::Bitmap> Bitmap::clone() const
 {
-    RefPtr<Gfx::Bitmap> new_bitmap {};
+    auto new_bitmap = Bitmap::try_create(format(), size(), scale());
-    if (m_purgeable) {
-        new_bitmap = Bitmap::try_create_purgeable(format(), size(), scale());
-    } else {
-        new_bitmap = Bitmap::try_create(format(), size(), scale());
-    }
 
-    if (!new_bitmap) {
+    if (!new_bitmap)
         return nullptr;
-    }
 
     VERIFY(size_in_bytes() == new_bitmap->size_in_bytes());
     memcpy(new_bitmap->scanline(0), scanline(0), size_in_bytes());
@@ -537,7 +521,6 @@ void Bitmap::fill(Color color)
 
 void Bitmap::set_volatile()
 {
-    VERIFY(m_purgeable);
     if (m_volatile)
         return;
 #ifdef __serenity__
@@ -552,7 +535,6 @@ void Bitmap::set_volatile()
 
 [[nodiscard]] bool Bitmap::set_nonvolatile()
 {
-    VERIFY(m_purgeable);
     if (!m_volatile)
         return true;
 #ifdef __serenity__
@@ -576,7 +558,7 @@ ShareableBitmap Bitmap::to_shareable_bitmap() const
     return ShareableBitmap(*bitmap);
 }
 
-Optional<BackingStore> Bitmap::try_allocate_backing_store(BitmapFormat format, IntSize const& size, int scale_factor, [[maybe_unused]] Purgeable purgeable)
+Optional<BackingStore> Bitmap::try_allocate_backing_store(BitmapFormat format, IntSize const& size, int scale_factor)
 {
     if (size_would_overflow(format, size, scale_factor))
         return {};
@@ -585,8 +567,6 @@ Optional<BackingStore> Bitmap::try_allocate_backing_store(BitmapFormat format, I
     const auto data_size_in_bytes = size_in_bytes(pitch, size.height() * scale_factor);
 
     int map_flags = MAP_ANONYMOUS | MAP_PRIVATE;
-    if (purgeable == Purgeable::Yes)
-        map_flags |= MAP_NORESERVE;
 #ifdef __serenity__
     void* data = mmap_with_name(nullptr, data_size_in_bytes, PROT_READ | PROT_WRITE, map_flags, 0, 0, String::formatted("GraphicsBitmap [{}]", size).characters());
 #else

Userland/Libraries/LibGfx/Bitmap.h

@@ -92,7 +92,6 @@ class Bitmap : public RefCounted<Bitmap> {
 public:
     [[nodiscard]] static RefPtr<Bitmap> try_create(BitmapFormat, const IntSize&, int intrinsic_scale = 1);
     [[nodiscard]] static RefPtr<Bitmap> try_create_shareable(BitmapFormat, const IntSize&, int intrinsic_scale = 1);
-    [[nodiscard]] static RefPtr<Bitmap> try_create_purgeable(BitmapFormat, const IntSize&, int intrinsic_scale = 1);
     [[nodiscard]] static RefPtr<Bitmap> try_create_wrapper(BitmapFormat, const IntSize&, int intrinsic_scale, size_t pitch, void*);
     [[nodiscard]] static RefPtr<Bitmap> try_load_from_file(String const& path, int scale_factor = 1);
     [[nodiscard]] static RefPtr<Bitmap> try_create_with_anonymous_buffer(BitmapFormat, Core::AnonymousBuffer, const IntSize&, int intrinsic_scale, const Vector<RGBA32>& palette);
@@ -226,7 +225,6 @@ public:
         set_pixel(physical_position.x(), physical_position.y(), color);
     }
 
-    [[nodiscard]] bool is_purgeable() const { return m_purgeable; }
     [[nodiscard]] bool is_volatile() const { return m_volatile; }
     void set_volatile();
     [[nodiscard]] bool set_nonvolatile();
@@ -235,15 +233,11 @@ public:
     [[nodiscard]] Core::AnonymousBuffer const& anonymous_buffer() const { return m_buffer; }
 
 private:
-    enum class Purgeable {
+    Bitmap(BitmapFormat, IntSize const&, int, BackingStore const&);
-        No,
-        Yes
-    };
-    Bitmap(BitmapFormat, const IntSize&, int, Purgeable, const BackingStore&);
     Bitmap(BitmapFormat, const IntSize&, int, size_t pitch, void*);
     Bitmap(BitmapFormat, Core::AnonymousBuffer, const IntSize&, int, const Vector<RGBA32>& palette);
 
-    static Optional<BackingStore> try_allocate_backing_store(BitmapFormat format, IntSize const& size, int scale_factor, Purgeable);
+    static Optional<BackingStore> try_allocate_backing_store(BitmapFormat format, IntSize const& size, int scale_factor);
 
     void allocate_palette_from_format(BitmapFormat, const Vector<RGBA32>& source_palette);
 
@@ -254,7 +248,6 @@ private:
     size_t m_pitch { 0 };
     BitmapFormat m_format { BitmapFormat::Invalid };
     bool m_needs_munmap { false };
-    bool m_purgeable { false };
     bool m_volatile { false };
     Core::AnonymousBuffer m_buffer;
 };

Userland/Libraries/LibGfx/DDSLoader.cpp

@@ -792,7 +792,7 @@ static bool decode_dds(DDSLoadingContext& context)
         dbgln_if(DDS_DEBUG, "There are {} bytes remaining, we need {} for mipmap level {} of the image", stream.remaining(), needed_bytes, mipmap_level);
         VERIFY(stream.remaining() >= needed_bytes);
 
-        context.bitmap = Bitmap::try_create_purgeable(BitmapFormat::BGRA8888, { width, height });
+        context.bitmap = Bitmap::try_create(BitmapFormat::BGRA8888, { width, height });
 
         decode_bitmap(stream, context, format, width, height);
 

Userland/Libraries/LibGfx/GIFLoader.cpp

@@ -299,10 +299,10 @@ static bool decode_frame(GIFLoadingContext& context, size_t frame_index)
     size_t start_frame = context.current_frame + 1;
     if (context.state < GIFLoadingContext::State::FrameComplete) {
         start_frame = 0;
-        context.frame_buffer = Bitmap::try_create_purgeable(BitmapFormat::BGRA8888, { context.logical_screen.width, context.logical_screen.height });
+        context.frame_buffer = Bitmap::try_create(BitmapFormat::BGRA8888, { context.logical_screen.width, context.logical_screen.height });
         if (!context.frame_buffer)
             return false;
-        context.prev_frame_buffer = Bitmap::try_create_purgeable(BitmapFormat::BGRA8888, { context.logical_screen.width, context.logical_screen.height });
+        context.prev_frame_buffer = Bitmap::try_create(BitmapFormat::BGRA8888, { context.logical_screen.width, context.logical_screen.height });
         if (!context.prev_frame_buffer)
             return false;
     } else if (frame_index < context.current_frame) {

Userland/Libraries/LibGfx/ICOLoader.cpp

@@ -246,7 +246,7 @@ static bool load_ico_bmp(ICOLoadingContext& context, ICOImageDescriptor& desc)
         return false;
     }
 
-    desc.bitmap = Bitmap::try_create_purgeable(BitmapFormat::BGRA8888, { desc.width, desc.height });
+    desc.bitmap = Bitmap::try_create(BitmapFormat::BGRA8888, { desc.width, desc.height });
     if (!desc.bitmap)
         return false;
     Bitmap& bitmap = *desc.bitmap;

Userland/Libraries/LibGfx/JPGLoader.cpp

@@ -1064,7 +1064,7 @@ static void ycbcr_to_rgb(const JPGLoadingContext& context, Vector<Macroblock>& m
 
 static bool compose_bitmap(JPGLoadingContext& context, const Vector<Macroblock>& macroblocks)
 {
-    context.bitmap = Bitmap::try_create_purgeable(BitmapFormat::BGRx8888, { context.frame.width, context.frame.height });
+    context.bitmap = Bitmap::try_create(BitmapFormat::BGRx8888, { context.frame.width, context.frame.height });
     if (!context.bitmap)
         return false;
 

Userland/Libraries/LibGfx/PNGLoader.cpp

@@ -606,7 +606,7 @@ static bool decode_png_bitmap_simple(PNGLoadingContext& context)
         }
     }
 
-    context.bitmap = Bitmap::try_create_purgeable(context.has_alpha() ? BitmapFormat::BGRA8888 : BitmapFormat::BGRx8888, { context.width, context.height });
+    context.bitmap = Bitmap::try_create(context.has_alpha() ? BitmapFormat::BGRA8888 : BitmapFormat::BGRx8888, { context.width, context.height });
 
     if (!context.bitmap) {
         context.state = PNGLoadingContext::State::Error;
@@ -726,7 +726,7 @@ static bool decode_adam7_pass(PNGLoadingContext& context, Streamer& streamer, in
 static bool decode_png_adam7(PNGLoadingContext& context)
 {
     Streamer streamer(context.decompression_buffer->data(), context.decompression_buffer->size());
-    context.bitmap = Bitmap::try_create_purgeable(context.has_alpha() ? BitmapFormat::BGRA8888 : BitmapFormat::BGRx8888, { context.width, context.height });
+    context.bitmap = Bitmap::try_create(context.has_alpha() ? BitmapFormat::BGRA8888 : BitmapFormat::BGRx8888, { context.width, context.height });
     if (!context.bitmap)
         return false;
 

Userland/Libraries/LibGfx/PortableImageLoaderCommon.h

@@ -178,7 +178,7 @@ static bool read_max_val(TContext& context, Streamer& streamer)
 template<typename TContext>
 static bool create_bitmap(TContext& context)
 {
-    context.bitmap = Bitmap::try_create_purgeable(BitmapFormat::BGRx8888, { context.width, context.height });
+    context.bitmap = Bitmap::try_create(BitmapFormat::BGRx8888, { context.width, context.height });
     if (!context.bitmap) {
         context.state = TContext::State::Error;
         return false;