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Fix non-breaking spaces

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Philipp Oppermann
2015-10-30 12:10:20 +01:00
parent 8ff462f831
commit 3453fbfa2f
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_posts/2015-08-25-entering-longmode.md
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@@ -281,7 +281,7 @@ setup_page_tables:
``` ```
Maybe I first explain how an assembly loop works. We use the `ecx` register as a counter variable, just like `i` in a for loop. After mapping the `ecx-th` entry, we increase `ecx` by one and jump to `.map_p2_table` again if it's still smaller 512. Maybe I first explain how an assembly loop works. We use the `ecx` register as a counter variable, just like `i` in a for loop. After mapping the `ecx-th` entry, we increase `ecx` by one and jump to `.map_p2_table` again if it's still smaller 512.
To map a P2 entry we first calculate the start address of its page in `eax`: The `ecx-th` entry needs to be mapped to `ecx * 2MiB`. Then we set the `present`, `writable`, and `huge page` bits and write it to the P2 entry. The address of the `ecx-th` entry in P2 is `p2_table + ecx * 8`, because each entry is 8 bytes large. To map a P2 entry we first calculate the start address of its page in `eax`: The `ecx-th` entry needs to be mapped to `ecx * 2MiB`. Then we set the `present`, `writable`, and `huge page` bits and write it to the P2 entry. The address of the `ecx-th` entry in P2 is `p2_table + ecx * 8`, because each entry is 8 bytes large.
Now the first gigabyte of our kernel is identity mapped and thus accessible through the same physical and virtual addresses. Now the first gigabyte of our kernel is identity mapped and thus accessible through the same physical and virtual addresses.