Mac OS X Internals

Preface xxv

Acknowledgments xxxi

About the Author xxxiii

Chapter 1 Origins of Mac OS X 1

1.1 Apple's Quest for the Operating System 2

1.2 The NeXT Chapter 9

1.3 The Mach Factor 15

1.4 Strategies 24

1.5 Toward Mac OS X 31

Chapter 2 An Overview of Mac OS X 43 2.1 Firmware 46

2.2 Bootloader 46

2.3 Darwin 46

2.4 The xnu Kernel 48

2.5 A User-Space View of the File System 57

2.6 The Runtime Architecture 61

2.7 The C Library 74

2.8 Bundles and Frameworks 76

2.9 Core Services 89

2.10 Application Services 90

2.11 Application Environments 101

2.12 User Interface 117

2.13 Programming 121

2.14 Security 131

2.15 Mac OS X Server 145

2.16 Networking 153

Chapter 3 Inside an Apple 155 3.1 The Power Mac G5 156

3.2 The G5: Lineage and Roadmap 166

3.3 The PowerPC 970FX 174

3.4 Software Conventions 224

3.5 Examples 240

Chapter 4 The Firmware and the Bootloader 263 4.1 Introduction 263

4.2 A Whole New World 266

4.3 Power-On Reset 271

4.4 Open Firmware 272

4.5 Forth 279

4.6 The Device Tree 289

4.7 Open Firmware Interfaces 298

4.8 Programming Examples 300

4.9 Firmware Boot Sequence 324

4.10 BootX 328

4.11 Alternate Booting Scenarios 340

4.12 Firmware Security 349

4.13 Launching the Kernel 352

4.14 The BootCache Optimization 353

4.15 The Boot-Time Kernel Arguments 355

4.16 The Extensible Firmware Interface 362

Chapter 5 Kernel and User-Level Startup 381 5.1 Arranging for the Kernel to Execute 382

5.2 Low-Level Processor Initialization 388

5.3 High-Level Processor Initialization 405

5.4 Mach Subsystem Initialization 421

5.5 The First Thread 432

5.6 I/O Kit Initialization 435

5.7 BSD Initialization 443

5.8 Launching the First User-Space Program 469

5.9 Slave Processors 470

5.10 User-Level Startup 472

Chapter 6 The xnu Kernel 501 6.1 xnu Source 501

6.2 Mach 510

6.3 A Flavor of the Mach APIs 519

6.4 Entering the Kernel 529

6.5 Exception Processing 543

6.6 System Call Processing 553

6.7 System Call Categories 557

6.8 Kernel Support for Debugging, Diagnostics, and Tracing 601

6.9 Virtual Machine Monitor 659

6.10 Compiling the Kernel 676

Chapter 7 Processes 683 7.1 Processes: From Early UNIC to Mac OS X 684

7.2 Mach Abstractions, Data Structures, and APIs 687

7.3 Many Threads of a New System 726

7.4 Scheduling 774

7.5 The execve() System Call 812

7.6 Launching Applications 828

Chapter 8 Memory 835 8.1 Looking Back 835

8.2 An Overview of Mac OS X Memory Management 838

8.3 Mac VM 846

8.4 Resident Memory 868

8.5 Virtual Memory Initialization during Bootstrap 877

8.6 The Mach VM User-Space Interface 878

8.7 Using the Mach VM Interfaces 893

8.8 Kernel and User Address Space Layouts 907

8.9 Universal Page Lists (UPLs) 912

8.10 Unified Buffer Cache (UBC) 913

8.11 The Dynamic Pager Program 918

8.12 The Update Daemon 921

8.13 System Shared Memory 922

8.14 Task Working Set Detection and Maintenance 942

8.15 Memory Allocation in User Space 948

8.16 Memory Allocation in the Kernel 980

8.17 Memory-Mapped Files 1001

8.18 64-bit Computing 1005

Chapter 9 Interprocess Communication 1021 9.1 Introduction 1021

9.2 Mach IPC: An Overview 1025

9.3 Mach IPC: The Mac OS X Implementation 1041

9.4 Name and Bootstrap Servers 1060

9.5 Using Mach IPC 1080

9.6 MIG 1094

9.7 Mach Exceptions 1112

9.8 Signals 1129

9.9 Pipes 1145

9.10 Named Pipes (Fifos) 1147

9.11 File Descriptor Passing 1148

9.12 XSI IPC 1155

9.13 POSIX IPC 1156

9.14 Distributed Objects 1164

9.15 Apple Events 1172

9.16 Notifications 1181

9.17 Core Foundation IPC 1197

9.18 Synchronization 1210

Chapter 10 Extending the Kernel 1233 10.1 A Driver down the Memory Lane 1233

10.2 The I/O Kit 1235

10.3 DART 1257

10.4 Dynamically Extending the Kernel 1259

10.5 Communicating with the Kernel 1269

10.6 Creating Kernel Extensions 1271

10.7 A Programming Tour of the I/O Kit's Functionality 1288

10.8 Debugging 1321

Chapter 11 File Systems 1345 11.1 Disks and Partitions 1345

11.2 Disk Arbitration 1353

11.3 The Implementation of Disk Devices 1362

11.4 Disk Images 1366

11.5 Files and File Descriptors 1374

11.6 The VFS Layer 1376

11.7 File System Types 1386

11.8 Spotlight 1409

11.9 Access Control Lists 1441

11.10 The Kauth Authorization Subsystem 1445

Chapter 12 The HFS Plus File System 1471 12.1 Analysis Tools 1474

12.2 Fundamental Concepts 1477

12.3 The Structure of an HFS+ Volume 1491

12.4 Reserved Areas 1493

12.5 The Volume Header 1493

12.6 The HFS Wrapper 1501

12.7 Special Files 1505

12.8 Examining HFS+ Features 1531

12.9 Optimizations 1558

12.10 Miscellaneous Features 1570

12.11 Comparing Mac OS X File Systems

12.12 Comparing HFS+ and NTFS 1582

Appendix A Mac OS X on x86-Based Macintosh Computers 1587 A.1 Hardware Differences 1587

A.2 Firmware and Booting 1589

A.3 Partitioning 1590

A.4 Universal Binaries 1591

A.5 Rosetta 1592

A.6 Byte Ordering 1594

A.7 Miscellaneous Changes 1594

Index 1599