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Point x86_64 links to version 0.5.2

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Philipp Oppermann
2019-04-26 11:35:47 +02:00
parent 74783de318
commit 8d0293e647
1 changed files with 9 additions and 9 deletions
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blog/content/second-edition/posts/09-paging-implementation/index.md
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@@ -548,7 +548,7 @@ The `VirtAddr` struct already provides methods to compute the indexes into the p
Inside the loop, we again use the `physical_memory_offset` to convert the frame into a page table reference. We then read the entry of the current page table and use the [`PageTableEntry::frame`] function to retrieve the mapped frame. If the entry is not mapped to a frame we return `None`. If the entry maps a huge 2MiB or 1GiB page we panic for now. Inside the loop, we again use the `physical_memory_offset` to convert the frame into a page table reference. We then read the entry of the current page table and use the [`PageTableEntry::frame`] function to retrieve the mapped frame. If the entry is not mapped to a frame we return `None`. If the entry maps a huge 2MiB or 1GiB page we panic for now.
[`PageTableEntry::frame`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/page_table/struct.PageTableEntry.html#method.frame [`PageTableEntry::frame`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/page_table/struct.PageTableEntry.html#method.frame
Let's test our translation function by translating some addresses: Let's test our translation function by translating some addresses:
@@ -601,17 +601,17 @@ The base of the abstraction are two traits that define various page table mappin
- The [`Mapper`] trait is generic over the page size and provides functions that operate on pages. Examples are [`translate_page`], which translates a given page to a frame of the same size, and [`map_to`], which creates a new mapping in the page table. - The [`Mapper`] trait is generic over the page size and provides functions that operate on pages. Examples are [`translate_page`], which translates a given page to a frame of the same size, and [`map_to`], which creates a new mapping in the page table.
- The [`MapperAllSizes`] trait implies that the implementor implements `Mapper` for all pages sizes. In addition, it provides functions that work with multiple page sizes such as [`translate_addr`] or the general [`translate`]. - The [`MapperAllSizes`] trait implies that the implementor implements `Mapper` for all pages sizes. In addition, it provides functions that work with multiple page sizes such as [`translate_addr`] or the general [`translate`].
[`Mapper`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/mapper/trait.Mapper.html [`Mapper`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/mapper/trait.Mapper.html
[`translate_page`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/mapper/trait.Mapper.html#tymethod.translate_page [`translate_page`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/mapper/trait.Mapper.html#tymethod.translate_page
[`map_to`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/mapper/trait.Mapper.html#tymethod.map_to [`map_to`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/mapper/trait.Mapper.html#tymethod.map_to
[`MapperAllSizes`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/mapper/trait.MapperAllSizes.html [`MapperAllSizes`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/mapper/trait.MapperAllSizes.html
[`translate_addr`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/mapper/trait.MapperAllSizes.html#method.translate_addr [`translate_addr`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/mapper/trait.MapperAllSizes.html#method.translate_addr
[`translate`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/mapper/trait.MapperAllSizes.html#tymethod.translate [`translate`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/mapper/trait.MapperAllSizes.html#tymethod.translate
The traits only define the interface, they don't provide any implementation. The `x86_64` crate currently provides two types that implement the traits: [`MappedPageTable`] and [`RecursivePageTable`]. The former type requires that each page table frame is mapped somewhere (e.g. at an offset). The latter type can be used when the level 4 table is [mapped recursively](#recursive-page-tables). The traits only define the interface, they don't provide any implementation. The `x86_64` crate currently provides two types that implement the traits: [`MappedPageTable`] and [`RecursivePageTable`]. The former type requires that each page table frame is mapped somewhere (e.g. at an offset). The latter type can be used when the level 4 table is [mapped recursively](#recursive-page-tables).
[`MappedPageTable`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/struct.MappedPageTable.html [`MappedPageTable`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/struct.MappedPageTable.html
[`RecursivePageTable`]: https://docs.rs/x86_64/0.5.1/x86_64/structures/paging/struct.RecursivePageTable.html [`RecursivePageTable`]: https://docs.rs/x86_64/0.5.2/x86_64/structures/paging/struct.RecursivePageTable.html
We have the complete physical memory mapped at `physical_memory_offset`, so we can use the `MappedPageTable` type. To initialize it, we create a new `init` function in our `memory` module: We have the complete physical memory mapped at `physical_memory_offset`, so we can use the `MappedPageTable` type. To initialize it, we create a new `init` function in our `memory` module: