Kernel: Make VirtualRangeAllocator setup functions propagate errors

If an internal allocation failure occurs while setting up a new VRA,
we'll now propagate the error to our caller instead of panicking.

3 files changed, 11 insertions, 9 deletions

diff --git a/Kernel/Memory/PageDirectory.cpp b/Kernel/Memory/PageDirectory.cpp
index 4461a294be..d75669da65 100644
--- a/Kernel/Memory/PageDirectory.cpp
+++ b/Kernel/Memory/PageDirectory.cpp
@@ -37,7 +37,7 @@ UNMAP_AFTER_INIT NonnullRefPtr<PageDirectory> PageDirectory::must_create_kernel_
 
     // make sure this starts in a new page directory to make MemoryManager::initialize_physical_pages() happy
     FlatPtr start_of_range = ((FlatPtr)end_of_kernel_image & ~(FlatPtr)0x1fffff) + 0x200000;
-    directory->m_range_allocator.initialize_with_range(VirtualAddress(start_of_range), KERNEL_PD_END - start_of_range);
+    MUST(directory->m_range_allocator.initialize_with_range(VirtualAddress(start_of_range), KERNEL_PD_END - start_of_range));
 
     return directory;
 }
@@ -50,11 +50,11 @@ ErrorOr<NonnullRefPtr<PageDirectory>> PageDirectory::try_create_for_userspace(Vi
     auto directory = TRY(adopt_nonnull_ref_or_enomem(new (nothrow) PageDirectory));
 
     if (parent_range_allocator) {
-        directory->m_range_allocator.initialize_from_parent(*parent_range_allocator);
+        TRY(directory->m_range_allocator.initialize_from_parent(*parent_range_allocator));
     } else {
         size_t random_offset = (get_fast_random<u8>() % 32 * MiB) & PAGE_MASK;
         u32 base = userspace_range_base + random_offset;
-        directory->m_range_allocator.initialize_with_range(VirtualAddress(base), userspace_range_ceiling - base);
+        TRY(directory->m_range_allocator.initialize_with_range(VirtualAddress(base), userspace_range_ceiling - base));
     }
 
     // NOTE: Take the MM lock since we need it for quickmap.
diff --git a/Kernel/Memory/VirtualRangeAllocator.cpp b/Kernel/Memory/VirtualRangeAllocator.cpp
index b9cbdf154d..d3e0d7b773 100644
--- a/Kernel/Memory/VirtualRangeAllocator.cpp
+++ b/Kernel/Memory/VirtualRangeAllocator.cpp
@@ -17,20 +17,22 @@ VirtualRangeAllocator::VirtualRangeAllocator()
 {
 }
 
-void VirtualRangeAllocator::initialize_with_range(VirtualAddress base, size_t size)
+ErrorOr<void> VirtualRangeAllocator::initialize_with_range(VirtualAddress base, size_t size)
 {
     m_total_range = { base, size };
-    m_available_ranges.insert(base.get(), VirtualRange { base, size });
+    TRY(m_available_ranges.try_insert(base.get(), VirtualRange { base, size }));
+    return {};
 }
 
-void VirtualRangeAllocator::initialize_from_parent(VirtualRangeAllocator const& parent_allocator)
+ErrorOr<void> VirtualRangeAllocator::initialize_from_parent(VirtualRangeAllocator const& parent_allocator)
 {
     SpinlockLocker lock(parent_allocator.m_lock);
     m_total_range = parent_allocator.m_total_range;
     m_available_ranges.clear();
     for (auto it = parent_allocator.m_available_ranges.begin(); !it.is_end(); ++it) {
-        m_available_ranges.insert(it.key(), *it);
+        TRY(m_available_ranges.try_insert(it.key(), VirtualRange(*it)));
     }
+    return {};
 }
 
 void VirtualRangeAllocator::dump() const
diff --git a/Kernel/Memory/VirtualRangeAllocator.h b/Kernel/Memory/VirtualRangeAllocator.h
index c09202e165..b469966d67 100644
--- a/Kernel/Memory/VirtualRangeAllocator.h
+++ b/Kernel/Memory/VirtualRangeAllocator.h
@@ -18,8 +18,8 @@ public:
     VirtualRangeAllocator();
     ~VirtualRangeAllocator() = default;
 
-    void initialize_with_range(VirtualAddress, size_t);
-    void initialize_from_parent(VirtualRangeAllocator const&);
+    ErrorOr<void> initialize_with_range(VirtualAddress, size_t);
+    ErrorOr<void> initialize_from_parent(VirtualRangeAllocator const&);
 
     ErrorOr<VirtualRange> try_allocate_anywhere(size_t, size_t alignment = PAGE_SIZE);
     ErrorOr<VirtualRange> try_allocate_specific(VirtualAddress, size_t);