cfenollosa_os-tutorial/22-malloc/README.md
2015-08-17 18:32:46 +02:00

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*Concepts you may want to Google beforehand: malloc*
**Goal: Implement a memory allocator**
We will add a kernel memory allocator to `libc/mem.c`. It is
implemented as a simple pointer to free memory, which keeps
growing.
The `kmalloc()` function can be used to request an aligned page,
and it will also return the real, physical address, for later use.
We'll change the `kernel.c` leaving all the "shell" code there,
Let's just try out the new `kmalloc()`, and check out that
our first page starts at 0x10000 (as hardcoded on `mem.c`) and
subsequent `kmalloc()`'s produce a new address which is
aligned 4096 bytes or 0x1000 from the previous one.
Note that we added a new `strings.c:hex_to_ascii()` for
nicer printing of hex numbers.
Another cosmetic modification is to rename `types.c` to
`type.c` for language consistency.
The rest of the files are unchanged from last lesson.