Kernel: Make File::truncate() take a u64

No point in taking a signed type here. We validate at the syscall layer
and then pass around a u64 from then on.

Kernel/FileSystem/Ext2FileSystem.cpp

@@ -1598,10 +1598,10 @@ KResult Ext2FSInode::chown(uid_t uid, gid_t gid)
     return KSuccess;
 }
 
-KResult Ext2FSInode::truncate(off_t size)
+KResult Ext2FSInode::truncate(u64 size)
 {
     LOCKER(m_lock);
-    if ((off_t)m_raw_inode.i_size == size)
+    if (static_cast<u64>(m_raw_inode.i_size) == size)
         return KSuccess;
     auto result = resize(size);
     if (result.is_error())

Kernel/FileSystem/Ext2FileSystem.h

@@ -70,7 +70,7 @@ private:
     virtual size_t directory_entry_count() const override;
     virtual KResult chmod(mode_t) override;
     virtual KResult chown(uid_t, gid_t) override;
-    virtual KResult truncate(off_t) override;
+    virtual KResult truncate(u64) override;
 
     bool write_directory(const Vector<FS::DirectoryEntry>&);
     void populate_lookup_cache() const;

Kernel/FileSystem/File.h

@@ -82,7 +82,7 @@ public:
 
     virtual String absolute_path(const FileDescription&) const = 0;
 
-    virtual KResult truncate(off_t) { return KResult(-EINVAL); }
+    virtual KResult truncate(u64) { return KResult(-EINVAL); }
     virtual KResult chown(uid_t, gid_t) { return KResult(-EBADF); }
     virtual KResult chmod(mode_t) { return KResult(-EBADF); }
 

Kernel/FileSystem/FileDescription.cpp

@@ -283,7 +283,7 @@ KResultOr<Region*> FileDescription::mmap(Process& process, VirtualAddress vaddr,
     return m_file->mmap(process, *this, vaddr, offset, size, prot);
 }
 
-KResult FileDescription::truncate(off_t length)
+KResult FileDescription::truncate(u64 length)
 {
     LOCKER(m_lock);
     return m_file->truncate(length);

Kernel/FileSystem/FileDescription.h

@@ -130,7 +130,7 @@ public:
 
     void set_original_inode(Badge<VFS>, NonnullRefPtr<Inode>&& inode) { m_inode = move(inode); }
 
-    KResult truncate(off_t);
+    KResult truncate(u64);
 
     off_t offset() const { return m_current_offset; }
 

Kernel/FileSystem/Inode.h

@@ -79,7 +79,7 @@ public:
     virtual size_t directory_entry_count() const = 0;
     virtual KResult chmod(mode_t) = 0;
     virtual KResult chown(uid_t, gid_t) = 0;
-    virtual KResult truncate(off_t) { return KSuccess; }
+    virtual KResult truncate(u64) { return KSuccess; }
     virtual KResultOr<NonnullRefPtr<Custody>> resolve_as_link(Custody& base, RefPtr<Custody>* out_parent = nullptr, int options = 0, int symlink_recursion_level = 0) const;
 
     LocalSocket* socket() { return m_socket.ptr(); }

Kernel/FileSystem/InodeFile.cpp

@@ -74,7 +74,7 @@ String InodeFile::absolute_path(const FileDescription& description) const
     return description.absolute_path();
 }
 
-KResult InodeFile::truncate(off_t size)
+KResult InodeFile::truncate(u64 size)
 {
     auto truncate_result = m_inode->truncate(size);
     if (truncate_result.is_error())

Kernel/FileSystem/InodeFile.h

@@ -51,7 +51,7 @@ public:
 
     virtual String absolute_path(const FileDescription&) const override;
 
-    virtual KResult truncate(off_t) override;
+    virtual KResult truncate(u64) override;
     virtual KResult chown(uid_t, gid_t) override;
     virtual KResult chmod(mode_t) override;
 

Kernel/FileSystem/TmpFS.cpp

@@ -327,7 +327,7 @@ KResult TmpFSInode::remove_child(const StringView& name)
     return KSuccess;
 }
 
-KResult TmpFSInode::truncate(off_t size)
+KResult TmpFSInode::truncate(u64 size)
 {
     LOCKER(m_lock);
     ASSERT(!is_directory());

Kernel/FileSystem/TmpFS.h

@@ -85,7 +85,7 @@ public:
     virtual size_t directory_entry_count() const override;
     virtual KResult chmod(mode_t) override;
     virtual KResult chown(uid_t, gid_t) override;
-    virtual KResult truncate(off_t) override;
+    virtual KResult truncate(u64) override;
     virtual int set_atime(time_t) override;
     virtual int set_ctime(time_t) override;
     virtual int set_mtime(time_t) override;

Kernel/Process.cpp

@@ -3868,7 +3868,7 @@ int Process::sys$ftruncate(int fd, off_t length)
         return -EBADF;
     if (!description->is_writable())
         return -EBADF;
-    return description->truncate(length);
+    return description->truncate(static_cast<u64>(length));
 }
 
 int Process::sys$watch_file(const char* user_path, size_t path_length)