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Developing a Multithreaded Kernel From Scratch!

4. Enabling the A20 line.mp4

04. Protected Mode Development · Video

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Course content

8 chapters · 243 lessons

Udemy - Developing a Multithreaded Kernel From Scratch! 2024-11

Readme

01. Introduction

1. Introduction

02. Setup And A Brief Explanation Of Kernel Development

1. What Is Memory 2. The Boot Process 3. Installing What We Need For Real Mode Development

03. Real Mode Development

1. Hello World Bootloader 1. Hello World Bootloader Commit 2. Understanding Real Mode 3. Segmentation Memory Model 4. Improving Our Bootloader 5. Preparing our bootloader to be booted on real hardware 6. Writing our bootloader to a USB stick 7. Booting the bootloader 8. The Interrupt Vector Table Explained 9. Implementing our own interrupts in real mode 10. Disk Access And How It Works 11. Reading from the hard disk

04. Protected Mode Development

1. What is Protected Mode 2. Source code 2. Switching To Protected Mode 3. Restructuring Our Project 4. Enabling the A20 line NOW 4. Source Code 5. Creating a Cross Compiler So We Can Code In C 6. Loading our 32 bit kernel into memory and working with debugging symbols 6. Source Code 7. Cleaning our object files 7. Source Code 8. Dealing With Alignment Issues 8. Source Code 9. C Code In Protected Mode 9. Source Code 10. Text Mode Explained 11. Source Code 11. Writing To The Screen, Hello World Tutorial 12. Interrupt Descriptor Table Explained 13. Implementing The Interrupt Descriptor Table 13. Source Code 14. Implementing In and Out Functions 14. Source Code 15. Programmable Interrupt Controller Explained 15. Source Code 16. Programmable Interrupt Controller Implementation 16. Source Code 17. Understanding The Heap And Memory Allocation 18. Implementing Our Heap 18. Source Code 19. Creating the enable interrupts function 19. Source Code 20. Understanding Paging 21. Implementing Paging 21. Source Code 22. Modifying the page table 22. Source Code 23. Preparing To Read From The Hard Disk 24. Reading from the disk in C with the ATA controller 24. Source Code 25. Improving Our Disk Driver 25. Source Code 26. What is a filesystem 27. Creating a path parser 27. Source Code 28. Creating a disk stream 28. Source Code 29. File Allocation Table Explained 30. Source Code 30. Starting To Create our FAT File system 31. Understanding the VFS(Virtual File System) Layer 32. Implementing our virtual filesystem core functionality 32. Source Code 33. implementing FAT16 filesystem driver core functionality 33. Source Code 34. Implementing FAT16 Structures 34. Source Code 35. Implementing The FAT16 Resolver Function 35. Source Code 36. Implementing the VFS fopen function 36. Source Code 37. Implementing FAT16 fopen function 37. Source Code 38. Implementing the VFS fread function 38. Source Code 39. Implementing FAT16 fread functionality 39. Source Code 40. Implementing the VFS fseek functionality 40. Source Code 41. Implementing the FAT16 fseek functionality 41. Source Code 42. Implementing the fstat VFS functionality 42. Source Code 43. Implementing the FAT16 fstat function 43. Source Code 44. Implementing the VFS fclose functionality 44. Source Code 45. Implementing the FAT16 fclose functionality 45. Source Code 46. Implementing a kernel panic 46. Source Code 47. Understanding User Land 48. Changing our kernel segment and data descriptors to be written in C 48. Source Code 49. Implementing The TSS(Task Switch Segment) 49. Source Code 50. Implementing Task Foundations 50. Source Code 51. Implementing Process Foundations Part 1 51. Source Code 52. Implementing Process Foundations Part 2 52. Source Code 53. Packing the GDT 53. Source Code 54. Implementing User Land Functionality 54. Source Code 55. Creating our first user process application 55. Source Code 56. Executing the process and dropping into user land privileges 56. Source Code 57. Changing the paging functionality 57. Source Code 58. Talking with the kernel from userland 59. Creating the interrupt 0x80 for user process to kernel communication 59. Source Code 60. Creating the ability to create and execute kernel commands 60. Source Code 61. Creating our first kernel command 61. Source Code 62. Calling our kernel command 62. Source Code 63. Copying strings from the tasks process 63. Source Code 63. Source Code Minor Change 64. Reading the task's stack 64. Source Code 65. Creating the print command in the kernel 65. Source Code 66. Understanding keyboard access in protected mode 67. Creating the virtual keyboard layer 67. Source Code 68. Creating the PS2 port keyboard driver part 1 68. Source Code 69. Improving our interrupt descriptor table design 69. Source Code 70. Creating a cleaner way to create interrupt handlers in the interrupt descriptor 70. Source Code 71. Changing The Current Process 71. Source Code 72. Creating the PS2 port keyboard driver part 2 72. Source Code 73. Getting a key from the keyboard buffer in user land 73. Source Code 74. Creating a putchar command that writes one character to the terminal 74. Source Code 75. Implementing backspace in the terminal 75. Source Code 76. Revising our stream reader 76. Source Code 77. Elf Files Explained 78. Implementing The Elf Loader - Part 1 78. Source Code 79. Implementing The Elf Loader - Part 2 79. Source Code 80. Implementing The Elf Loader - Part 3 80. Source Code 81. Implementing The Elf Loader - Part 4 81. Source Code 82. Implementing The Elf Loader - Part 5 82. Source Code 83. Implementing The Elf Loader - Part 6 83. Source Code 84. Source Code 84. Writing User Programs In C 85. Implementing system print in stdlib 85. Source Code 85. Source Code - Revised (Use this one) 86. Implementing system get key in stdlib 86. Source Code 87. Implementing Malloc In Our stdlib 87. Source Code 88. Implementing Free In Our stdlib 88. Source Code 89. Changing the way we map virtual pages for the process 89. Source Code 90. Implementing itoa function 90. Source Code 91. Implementing the putchar function 91. Source Code 92. Implementing the printf function 92. Source Code 93. Implementing the ability to read lines 93. Source Code 94. Creating a shell 94. Source Code 95. Loading other programs from our shell 95. Source Code 96. Creating some important stdlib functions 96. Source Code 97. Memory Mapping malloc in stdlib 97. Source Code 98. Memory Unmapping free In stdlib 98. Source Code 99. Process arguments - Part 1 99. Source Code 100. Process Arguments - Part 2 100. Source Code 101. Process Arguments - Part 3 101. Source Code 102. Implementing A 'System' Command 102. Source Code 103. Implementing program termination 103. Source Code 104. Handling program crashes 104. Source Code 105. Creating an exit command 105. Source Code 106. Handling caps lock, upper case and lower case letters 106. Source Code 107. Running multiple tasks at the same time multi-tasking 107. Source Code

05. Optional

1. README 2. Changing our fat16_new_fat_item_for_directory_item function 3. Changing our fat16_open function 3. Source Code 4. Changing our fat16_get_root_directory function 4. Source Code 5. Changing our process_load_binary function 5. Source Code 6. Improvements to our fat16_to_proper_string function 6. Source Code 7. Changing our restore_general_purpose_registers function 7. Source Code 8. Final Kernel Improvements 8. Source Code

06. Assembly Language Catchup

1. Assembly Catchup! 2. What is assembly language 3. Emu8086 Download 3. Installing the emulator 4. Hello World In Assembly 5. Transistors And Logic Gates Understanding The Processor 6. Registers in the 8086 7. Segmentation Memory Model Explained 8. The Stack, Subroutines And Endiness Explained

07. Conclusion

1. Bonus Lecture 1. Kernel Development Books

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