Kernel: Add implied auto-specifiers in FileSystem

As per clang-tidy.

Kernel/FileSystem/Custody.cpp

@@ -73,7 +73,7 @@ ErrorOr<NonnullOwnPtr<KString>> Custody::try_serialize_absolute_path() const
 
     Vector<Custody const*, 32> custody_chain;
     size_t path_length = 0;
-    for (auto* custody = this; custody; custody = custody->parent()) {
+    for (auto const* custody = this; custody; custody = custody->parent()) {
         custody_chain.append(custody);
         path_length += custody->m_name->length() + 1;
     }
@@ -85,7 +85,7 @@ ErrorOr<NonnullOwnPtr<KString>> Custody::try_serialize_absolute_path() const
     for (size_t custody_index = custody_chain.size() - 1; custody_index > 0; --custody_index) {
         buffer[string_index] = '/';
         ++string_index;
-        auto& custody_name = *custody_chain[custody_index - 1]->m_name;
+        auto const& custody_name = *custody_chain[custody_index - 1]->m_name;
         __builtin_memcpy(buffer + string_index, custody_name.characters(), custody_name.length());
         string_index += custody_name.length();
     }
@@ -99,7 +99,7 @@ String Custody::absolute_path() const
     if (!parent())
         return "/";
     Vector<Custody const*, 32> custody_chain;
-    for (auto* custody = this; custody; custody = custody->parent())
+    for (auto const* custody = this; custody; custody = custody->parent())
         custody_chain.append(custody);
     StringBuilder builder;
     for (int i = custody_chain.size() - 2; i >= 0; --i) {

Kernel/FileSystem/Ext2FileSystem.cpp

@@ -95,7 +95,7 @@ ErrorOr<void> Ext2FS::initialize()
     bool success = raw_read_blocks(2, (sizeof(ext2_super_block) / logical_block_size()), super_block_buffer);
     VERIFY(success);
 
-    auto& super_block = this->super_block();
+    auto const& super_block = this->super_block();
     if constexpr (EXT2_DEBUG) {
         dmesgln("Ext2FS: super block magic: {:04x} (super block size: {})", super_block.s_magic, sizeof(ext2_super_block));
     }
@@ -138,7 +138,7 @@ ErrorOr<void> Ext2FS::initialize()
 
     if constexpr (EXT2_DEBUG) {
         for (unsigned i = 1; i <= m_block_group_count; ++i) {
-            auto& group = group_descriptor(i);
+            auto const& group = group_descriptor(i);
             dbgln("Ext2FS: group[{}] ( block_bitmap: {}, inode_bitmap: {}, inode_table: {} )", i, group.bg_block_bitmap, group.bg_inode_bitmap, group.bg_inode_table);
         }
     }
@@ -154,7 +154,7 @@ Ext2FSInode& Ext2FS::root_inode()
 
 bool Ext2FS::find_block_containing_inode(InodeIndex inode, BlockIndex& block_index, unsigned& offset) const
 {
-    auto& super_block = this->super_block();
+    auto const& super_block = this->super_block();
 
     if (inode != EXT2_ROOT_INO && inode < EXT2_FIRST_INO(&super_block))
         return false;
@@ -162,7 +162,7 @@ bool Ext2FS::find_block_containing_inode(InodeIndex inode, BlockIndex& block_ind
     if (inode > super_block.s_inodes_count)
         return false;
 
-    auto& bgd = group_descriptor(group_index_from_inode(inode));
+    auto const& bgd = group_descriptor(group_index_from_inode(inode));
 
     u64 full_offset = ((inode.value() - 1) % inodes_per_group()) * inode_size();
     block_index = bgd.bg_inode_table + (full_offset >> EXT2_BLOCK_SIZE_BITS(&super_block));
@@ -1283,7 +1283,7 @@ auto Ext2FS::allocate_blocks(GroupIndex preferred_group_index, size_t count) ->
         }
 
         VERIFY(found_a_group);
-        auto& bgd = group_descriptor(group_index);
+        auto const& bgd = group_descriptor(group_index);
 
         auto* cached_bitmap = TRY(get_bitmap_block(bgd.bg_block_bitmap));
 
@@ -1338,7 +1338,7 @@ ErrorOr<InodeIndex> Ext2FS::allocate_inode(GroupIndex preferred_group)
 
     dbgln_if(EXT2_DEBUG, "Ext2FS: allocate_inode: found suitable group [{}] for new inode :^)", group_index);
 
-    auto& bgd = group_descriptor(group_index);
+    auto const& bgd = group_descriptor(group_index);
     unsigned inodes_in_group = min(inodes_per_group(), super_block().s_inodes_count);
     InodeIndex first_inode_in_group = (group_index.value() - 1) * inodes_per_group() + 1;
 
@@ -1387,7 +1387,7 @@ ErrorOr<bool> Ext2FS::get_inode_allocation_state(InodeIndex index) const
     if (index == 0)
         return EINVAL;
     auto group_index = group_index_from_inode(index);
-    auto& bgd = group_descriptor(group_index);
+    auto const& bgd = group_descriptor(group_index);
     unsigned index_in_group = index.value() - ((group_index.value() - 1) * inodes_per_group());
     unsigned bit_index = (index_in_group - 1) % inodes_per_group();
 

Kernel/FileSystem/ISO9660FileSystem.cpp

@@ -240,7 +240,7 @@ ErrorOr<void> ISO9660FS::parse_volume_set()
             return EIO;
         }
 
-        auto header = reinterpret_cast<ISO::VolumeDescriptorHeader const*>(block->data());
+        auto const* header = reinterpret_cast<ISO::VolumeDescriptorHeader const*>(block->data());
         if (StringView { header->identifier, 5 } != "CD001") {
             dbgln_if(ISO9660_DEBUG, "Header magic at volume descriptor {} is not valid", current_block_index - first_data_area_block);
             return EIO;
@@ -248,7 +248,7 @@ ErrorOr<void> ISO9660FS::parse_volume_set()
 
         switch (header->type) {
         case ISO::VolumeDescriptorType::PrimaryVolumeDescriptor: {
-            auto primary_volume = reinterpret_cast<ISO::PrimaryVolumeDescriptor const*>(header);
+            auto const* primary_volume = reinterpret_cast<ISO::PrimaryVolumeDescriptor const*>(header);
             m_primary_volume = adopt_own_if_nonnull(new ISO::PrimaryVolumeDescriptor(*primary_volume));
             break;
         }
@@ -611,7 +611,7 @@ time_t ISO9660Inode::parse_numerical_date_time(ISO::NumericalDateAndTime const&
 
 StringView ISO9660Inode::get_normalized_filename(ISO::DirectoryRecordHeader const& record, Bytes buffer)
 {
-    auto file_identifier = reinterpret_cast<u8 const*>(&record + 1);
+    auto const* file_identifier = reinterpret_cast<u8 const*>(&record + 1);
     auto filename = StringView { file_identifier, record.file_identifier_length };
 
     if (filename.length() == 1) {

Kernel/FileSystem/Inode.cpp

@@ -296,14 +296,14 @@ ErrorOr<void> Inode::can_apply_flock(OpenFileDescription const& description, flo
     MutexLocker locker(m_inode_lock, Mutex::Mode::Shared);
 
     if (new_lock.l_type == F_UNLCK) {
-        for (auto& lock : m_flocks) {
+        for (auto const& lock : m_flocks) {
             if (&description == lock.owner && lock.start == new_lock.l_start && lock.len == new_lock.l_len)
                 return {};
         }
         return EINVAL;
     }
 
-    for (auto& lock : m_flocks) {
+    for (auto const& lock : m_flocks) {
         if (!range_overlap(lock.start, lock.len, new_lock.l_start, new_lock.l_len))
             continue;
 
@@ -348,7 +348,7 @@ ErrorOr<void> Inode::get_flock(OpenFileDescription const& description, Userspace
 
     MutexLocker locker(m_inode_lock, Mutex::Mode::Shared);
 
-    for (auto& lock : m_flocks) {
+    for (auto const& lock : m_flocks) {
         if (!range_overlap(lock.start, lock.len, lookup.l_start, lookup.l_len))
             continue;
 

Kernel/FileSystem/OpenFileDescription.cpp

@@ -87,7 +87,7 @@ Thread::FileBlocker::BlockFlags OpenFileDescription::should_unblock(Thread::File
     // TODO: Implement Thread::FileBlocker::BlockFlags::Exception
 
     if (has_any_flag(block_flags, BlockFlags::SocketFlags)) {
-        auto* sock = socket();
+        auto const* sock = socket();
         VERIFY(sock);
         if (has_flag(block_flags, BlockFlags::Accept) && sock->can_accept())
             unblock_flags |= BlockFlags::Accept;

Kernel/FileSystem/Plan9FileSystem.cpp

@@ -491,7 +491,7 @@ bool Plan9FS::is_complete(const ReceiveCompletion& completion)
 
 ErrorOr<void> Plan9FS::post_message(Message& message, RefPtr<ReceiveCompletion> completion)
 {
-    auto& buffer = message.build();
+    auto const& buffer = message.build();
     const u8* data = buffer.data();
     size_t size = buffer.size();
     auto& description = file_description();
@@ -562,7 +562,7 @@ ErrorOr<void> Plan9FS::read_and_dispatch_one_message()
 
     auto optional_completion = m_completions.get(header.tag);
     if (optional_completion.has_value()) {
-        auto completion = optional_completion.value();
+        auto* completion = optional_completion.value();
         SpinlockLocker lock(completion->lock);
         completion->result = {};
         completion->message = adopt_own_if_nonnull(new (nothrow) Message { move(buffer) });

Kernel/FileSystem/SysFS.cpp

@@ -52,7 +52,7 @@ ErrorOr<void> SysFSRootDirectory::traverse_as_directory(FileSystemID fsid, Funct
     TRY(callback({ ".", { fsid, component_index() }, 0 }));
     TRY(callback({ "..", { fsid, 0 }, 0 }));
 
-    for (auto& component : m_components) {
+    for (auto const& component : m_components) {
         InodeIdentifier identifier = { fsid, component.component_index() };
         TRY(callback({ component.name(), identifier, 0 }));
     }