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Update to new internal link syntax

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Philipp Oppermann
2019-09-29 15:24:21 +02:00
parent 0b971c9128
commit a133ea82cf
29 changed files with 117 additions and 119 deletions
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blog/content/first-edition/posts/02-entering-longmode/index.md
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@@ -11,7 +11,7 @@ updated = "2015-10-29"
In the [previous post] we created a minimal multiboot kernel. It just prints `OK` and hangs. The goal is to extend it and call 64-bit [Rust] code. But the CPU is currently in [protected mode] and allows only 32-bit instructions and up to 4GiB memory. So we need to set up _Paging_ and switch to the 64-bit [long mode] first.
[previous post]: ./first-edition/posts/01-multiboot-kernel/index.md
[previous post]: @/first-edition/posts/01-multiboot-kernel/index.md
[Rust]: http://www.rust-lang.org/
[protected mode]: https://en.wikipedia.org/wiki/Protected_mode
[long mode]: https://en.wikipedia.org/wiki/Long_mode
@@ -39,7 +39,7 @@ error:
At address `0xb8000` begins the so-called [VGA text buffer]. It's an array of screen characters that are displayed by the graphics card. A [future post] will cover the VGA buffer in detail and create a Rust interface to it. But for now, manual bit-fiddling is the easiest option.
[VGA text buffer]: https://en.wikipedia.org/wiki/VGA-compatible_text_mode
[future post]: ./first-edition/posts/04-printing-to-screen/index.md
[future post]: @/first-edition/posts/04-printing-to-screen/index.md
A screen character consists of a 8 bit color code and a 8 bit [ASCII] character. We used the color code `4f` for all characters, which means white text on red background. `0x52` is an ASCII `R`, `0x45` is an `E`, `0x3a` is a `:`, and `0x20` is a space. The second space is overwritten by the given ASCII byte. Finally the CPU is stopped with the `hlt` instruction.
@@ -492,8 +492,8 @@ _Congratulations_! You have successfully wrestled through this CPU configuration
#### One Last Thing
Above, we reloaded the code segment register `cs` with the new GDT offset. However, the data segment registers `ss`, `ds`, `es`, `fs`, and `gs` still contain the data segment offsets of the old GDT. This isn't necessarily bad, since they're ignored by almost all instructions in 64-bit mode. However, there are a few instructions that expect a valid data segment descriptor _or the null descriptor_ in those registers. An example is the the [iretq] instruction that we'll need in the [_Returning from Exceptions_] post.
[iretq]: ./first-edition/extra/naked-exceptions/03-returning-from-exceptions/index.md#the
[_Returning from Exceptions_]: ./first-edition/extra/naked-exceptions/03-returning-from-exceptions/index.md
[iretq]: @/first-edition/extra/naked-exceptions/03-returning-from-exceptions/index.md#the
[_Returning from Exceptions_]: @/first-edition/extra/naked-exceptions/03-returning-from-exceptions/index.md
To avoid future problems, we reload all data segment registers with null:
@@ -515,7 +515,7 @@ long_mode_start:
It's time to finally leave assembly behind and switch to [Rust]. Rust is a systems language without garbage collections that guarantees memory safety. Through a real type system and many abstractions it feels like a high-level language but can still be low-level enough for OS development. The [next post] describes the Rust setup.
[Rust]: https://www.rust-lang.org/
[next post]: ./first-edition/posts/03-set-up-rust/index.md
[next post]: @/first-edition/posts/03-set-up-rust/index.md
## Footnotes
[^hardware_lookup]: In the x86 architecture, the page tables are _hardware walked_, so the CPU will look at the table on its own when it needs a translation. Other architectures, for example MIPS, just throw an exception and let the OS translate the virtual address.