AK: Make Bitmap construction OOM-fallible

Author: https://github.com/IdanHo
Commit: https://github.com/SerenityOS/serenity/commit/871a53db76
Pull-request: https://github.com/SerenityOS/serenity/pull/12422

AK/Bitmap.h

@@ -7,10 +7,12 @@
 #pragma once
 
 #include <AK/BitmapView.h>
+#include <AK/Error.h>
 #include <AK/Noncopyable.h>
 #include <AK/Optional.h>
 #include <AK/Platform.h>
 #include <AK/StdLibExtras.h>
+#include <AK/Try.h>
 #include <AK/Types.h>
 #include <AK/kmalloc.h>
 
@@ -20,16 +22,26 @@ class Bitmap : public BitmapView {
     AK_MAKE_NONCOPYABLE(Bitmap);
 
 public:
-    Bitmap() = default;
-
-    Bitmap(size_t size, bool default_value)
-        : BitmapView(static_cast<u8*>(kmalloc(ceil_div(size, static_cast<size_t>(8)))), size)
-        , m_is_owning(true)
+    static ErrorOr<Bitmap> try_create(size_t size, bool default_value)
     {
         VERIFY(size != 0);
-        fill(default_value);
+
+        auto* data = kmalloc(ceil_div(size, static_cast<size_t>(8)));
+        if (!data)
+            return Error::from_errno(ENOMEM);
+
+        auto bitmap = Bitmap { (u8*)data, size, true };
+        bitmap.fill(default_value);
+        return bitmap;
     }
 
+    static Bitmap must_create(size_t size, bool default_value)
+    {
+        return MUST(try_create(size, default_value));
+    }
+
+    Bitmap() = default;
+
     Bitmap(u8* data, size_t size, bool is_owning = false)
         : BitmapView(data, size)
         , m_is_owning(is_owning)

Kernel/Bus/PCI/Controller/HostBridge.cpp

@@ -19,7 +19,7 @@ NonnullOwnPtr<HostBridge> HostBridge::must_create_with_io_access()
 
 HostBridge::HostBridge(PCI::Domain const& domain)
     : HostController(domain)
-    , m_enumerated_buses(256, false)
+    , m_enumerated_buses(Bitmap::try_create(256, false).release_value_but_fixme_should_propagate_errors())
 {
 }
 

Kernel/Memory/AnonymousVMObject.cpp

@@ -253,7 +253,7 @@ NonnullRefPtr<PhysicalPage> AnonymousVMObject::allocate_committed_page(Badge<Reg
 Bitmap& AnonymousVMObject::ensure_cow_map()
 {
     if (m_cow_map.is_null())
-        m_cow_map = Bitmap { page_count(), true };
+        m_cow_map = Bitmap::try_create(page_count(), true).release_value_but_fixme_should_propagate_errors();
     return m_cow_map;
 }
 

Kernel/Memory/InodeVMObject.cpp

@@ -12,14 +12,14 @@ namespace Kernel::Memory {
 InodeVMObject::InodeVMObject(Inode& inode, FixedArray<RefPtr<PhysicalPage>>&& new_physical_pages)
     : VMObject(move(new_physical_pages))
     , m_inode(inode)
-    , m_dirty_pages(page_count(), false)
+    , m_dirty_pages(Bitmap::try_create(page_count(), false).release_value_but_fixme_should_propagate_errors())
 {
 }
 
 InodeVMObject::InodeVMObject(InodeVMObject const& other, FixedArray<RefPtr<PhysicalPage>>&& new_physical_pages)
     : VMObject(move(new_physical_pages))
     , m_inode(other.m_inode)
-    , m_dirty_pages(page_count(), false)
+    , m_dirty_pages(Bitmap::try_create(page_count(), false).release_value_but_fixme_should_propagate_errors())
 {
     for (size_t i = 0; i < page_count(); ++i)
         m_dirty_pages.set(i, other.m_dirty_pages.get(i));

Tests/AK/TestBitmap.cpp

@@ -16,14 +16,14 @@ TEST_CASE(construct_empty)
 
 TEST_CASE(find_first_set)
 {
-    Bitmap bitmap(128, false);
+    auto bitmap = Bitmap::must_create(128, false);
     bitmap.set(69, true);
     EXPECT_EQ(bitmap.find_first_set().value(), 69u);
 }
 
 TEST_CASE(find_first_unset)
 {
-    Bitmap bitmap(128, true);
+    auto bitmap = Bitmap::must_create(128, true);
     bitmap.set(51, false);
     EXPECT_EQ(bitmap.find_first_unset().value(), 51u);
 }
@@ -31,7 +31,7 @@ TEST_CASE(find_first_unset)
 TEST_CASE(find_one_anywhere_set)
 {
     {
-        Bitmap bitmap(168, false);
+        auto bitmap = Bitmap::must_create(168, false);
         bitmap.set(34, true);
         bitmap.set(97, true);
         EXPECT_EQ(bitmap.find_one_anywhere_set(0).value(), 34u);
@@ -48,7 +48,7 @@ TEST_CASE(find_one_anywhere_set)
         EXPECT_EQ(bitmap.find_one_anywhere_set(128).value(), 34u);
     }
     {
-        Bitmap bitmap(128 + 24, false);
+        auto bitmap = Bitmap::must_create(128 + 24, false);
         bitmap.set(34, true);
         bitmap.set(126, true);
         EXPECT_EQ(bitmap.find_one_anywhere_set(0).value(), 34u);
@@ -56,7 +56,7 @@ TEST_CASE(find_one_anywhere_set)
         EXPECT_EQ(bitmap.find_one_anywhere_set(64).value(), 126u);
     }
     {
-        Bitmap bitmap(32, false);
+        auto bitmap = Bitmap::must_create(32, false);
         bitmap.set(12, true);
         bitmap.set(24, true);
         auto got = bitmap.find_one_anywhere_set(0).value();
@@ -67,7 +67,7 @@ TEST_CASE(find_one_anywhere_set)
 TEST_CASE(find_one_anywhere_unset)
 {
     {
-        Bitmap bitmap(168, true);
+        auto bitmap = Bitmap::must_create(168, true);
         bitmap.set(34, false);
         bitmap.set(97, false);
         EXPECT_EQ(bitmap.find_one_anywhere_unset(0).value(), 34u);
@@ -84,7 +84,7 @@ TEST_CASE(find_one_anywhere_unset)
         EXPECT_EQ(bitmap.find_one_anywhere_unset(128).value(), 34u);
     }
     {
-        Bitmap bitmap(128 + 24, true);
+        auto bitmap = Bitmap::must_create(128 + 24, true);
         bitmap.set(34, false);
         bitmap.set(126, false);
         EXPECT_EQ(bitmap.find_one_anywhere_unset(0).value(), 34u);
@@ -92,7 +92,7 @@ TEST_CASE(find_one_anywhere_unset)
         EXPECT_EQ(bitmap.find_one_anywhere_unset(64).value(), 126u);
     }
     {
-        Bitmap bitmap(32, true);
+        auto bitmap = Bitmap::must_create(32, true);
         bitmap.set(12, false);
         bitmap.set(24, false);
         auto got = bitmap.find_one_anywhere_unset(0).value();
@@ -102,7 +102,7 @@ TEST_CASE(find_one_anywhere_unset)
 
 TEST_CASE(find_first_range)
 {
-    Bitmap bitmap(128, true);
+    auto bitmap = Bitmap::must_create(128, true);
     bitmap.set(47, false);
     bitmap.set(48, false);
     bitmap.set(49, false);
@@ -118,7 +118,7 @@ TEST_CASE(find_first_range)
 TEST_CASE(set_range)
 {
     {
-        Bitmap bitmap(128, false);
+        auto bitmap = Bitmap::must_create(128, false);
         bitmap.set_range(41, 10, true);
         EXPECT_EQ(bitmap.get(40), false);
         EXPECT_EQ(bitmap.get(41), true);
@@ -134,7 +134,7 @@ TEST_CASE(set_range)
         EXPECT_EQ(bitmap.get(51), false);
     }
     {
-        Bitmap bitmap(288, false);
+        auto bitmap = Bitmap::must_create(288, false);
         bitmap.set_range(48, 32, true);
         bitmap.set_range(94, 39, true);
         bitmap.set_range(190, 71, true);
@@ -152,12 +152,12 @@ TEST_CASE(set_range)
 TEST_CASE(find_first_fit)
 {
     {
-        Bitmap bitmap(32, true);
+        auto bitmap = Bitmap::must_create(32, true);
         auto fit = bitmap.find_first_fit(1);
         EXPECT_EQ(fit.has_value(), false);
     }
     {
-        Bitmap bitmap(32, true);
+        auto bitmap = Bitmap::must_create(32, true);
         bitmap.set(31, false);
         auto fit = bitmap.find_first_fit(1);
         EXPECT_EQ(fit.has_value(), true);
@@ -165,7 +165,7 @@ TEST_CASE(find_first_fit)
     }
 
     for (size_t i = 0; i < 128; ++i) {
-        Bitmap bitmap(128, true);
+        auto bitmap = Bitmap::must_create(128, true);
         bitmap.set(i, false);
         auto fit = bitmap.find_first_fit(1);
         EXPECT_EQ(fit.has_value(), true);
@@ -173,7 +173,7 @@ TEST_CASE(find_first_fit)
     }
 
     for (size_t i = 0; i < 127; ++i) {
-        Bitmap bitmap(128, true);
+        auto bitmap = Bitmap::must_create(128, true);
         bitmap.set(i, false);
         bitmap.set(i + 1, false);
         auto fit = bitmap.find_first_fit(2);
@@ -184,7 +184,7 @@ TEST_CASE(find_first_fit)
     size_t bitmap_size = 1024;
     for (size_t chunk_size = 1; chunk_size < 64; ++chunk_size) {
         for (size_t i = 0; i < bitmap_size - chunk_size; ++i) {
-            Bitmap bitmap(bitmap_size, true);
+            auto bitmap = Bitmap::must_create(bitmap_size, true);
             for (size_t c = 0; c < chunk_size; ++c)
                 bitmap.set(i + c, false);
             auto fit = bitmap.find_first_fit(chunk_size);
@@ -196,7 +196,7 @@ TEST_CASE(find_first_fit)
 
 TEST_CASE(find_longest_range_of_unset_bits_edge)
 {
-    Bitmap bitmap(36, true);
+    auto bitmap = Bitmap::must_create(36, true);
     bitmap.set_range(32, 4, false);
     size_t found_range_size = 0;
     auto result = bitmap.find_longest_range_of_unset_bits(1, found_range_size);
@@ -206,7 +206,7 @@ TEST_CASE(find_longest_range_of_unset_bits_edge)
 
 TEST_CASE(count_in_range)
 {
-    Bitmap bitmap(256, false);
+    auto bitmap = Bitmap::must_create(256, false);
     bitmap.set(14, true);
     bitmap.set(17, true);
     bitmap.set(19, true);
@@ -252,14 +252,14 @@ TEST_CASE(count_in_range)
 TEST_CASE(byte_aligned_access)
 {
     {
-        Bitmap bitmap(16, true);
+        auto bitmap = Bitmap::must_create(16, true);
         EXPECT_EQ(bitmap.count_in_range(0, 16, true), 16u);
         EXPECT_EQ(bitmap.count_in_range(8, 8, true), 8u);
         EXPECT_EQ(bitmap.count_in_range(0, 8, true), 8u);
         EXPECT_EQ(bitmap.count_in_range(4, 8, true), 8u);
     }
     {
-        Bitmap bitmap(16, false);
+        auto bitmap = Bitmap::must_create(16, false);
         bitmap.set_range(4, 8, true);
         EXPECT_EQ(bitmap.count_in_range(0, 16, true), 8u);
         EXPECT_EQ(bitmap.count_in_range(8, 8, true), 4u);
@@ -267,7 +267,7 @@ TEST_CASE(byte_aligned_access)
         EXPECT_EQ(bitmap.count_in_range(4, 8, true), 8u);
     }
     {
-        Bitmap bitmap(8, false);
+        auto bitmap = Bitmap::must_create(8, false);
         bitmap.set(2, true);
         bitmap.set(4, true);
         EXPECT_EQ(bitmap.count_in_range(0, 2, true), 0u);

Userland/DevTools/Profiler/Profile.h

@@ -47,7 +47,7 @@ public:
     void will_track_seen_events(size_t profile_event_count)
     {
         if (m_seen_events.size() != profile_event_count)
-            m_seen_events = Bitmap { profile_event_count, false };
+            m_seen_events = Bitmap::must_create(profile_event_count, false);
     }
     bool has_seen_event(size_t event_index) const { return m_seen_events.get(event_index); }
     void did_see_event(size_t event_index) { m_seen_events.set(event_index, true); }