apio/Luna
1
1
Fork 0
Code Issues Pull Requests Actions Projects Releases 8 Wiki Activity
732 Commits 3 Branches 21 Tags 11 MiB
e5cf32c7b3
Commit Graph

73 Commits

Author SHA1 Message Date
apio
e5cf32c7b3 Kernel: Introduce page ownership 
Some pages, such as framebuffer pages, are not physical memory frames reserved for the current process.
Some, such as the framebuffer, may be shared between all processes.
Yet, on exit() or on exec(), a process frees all frames mapped into its address spaces.
And on fork(), it copies all data between frames. So how could we map framebuffers.

Simple: we use one of the bits in page table entries which are available to the OS, and mark whether that page is owned by the current process.

If it is owned, it will be:
- Freed on address space destruction
- Its data will be copied to a new page owned by the child process on fork()

If it is not owned, it will be:
- Left alone on address space destruction
- On fork(), the child's virtual page will be mapped to the same physical frame as the parent

This still needs a bit more work, such as keeping a reference of how many processes use a page to free it when all processes using it exit/exec.
This should be done for MAP_SHARED mappings, for example, since they are not permanent forever,
unlike the framebuffer for example.
 2022-11-02 19:32:28 +01:00
apio
22740e69bf Kernel: Add support for the NX bit 
Not support, actually. We now REQUIRE it.
 2022-11-02 18:34:57 +01:00
apio
712f4f5e51 KernelHeap: Add more debug logging 2022-10-20 18:49:33 +02:00
apio
9d0dfbaedf PMM: Log invalid frees 2022-10-20 18:49:12 +02:00
apio
7e9744419e sh: Improve it 2022-10-19 20:16:21 +02:00
apio
b035795eb3 Kernel: Move errno.h and (k)assert.h out of the main include directory 
This is mostly so IDEs don't pick them up instead of the userspace headers :)
 2022-10-19 17:41:23 +02:00
apio
755242719c VMM: Add a few memsets 
This seems to fix exec() making weird page tables!!
 2022-10-19 07:56:08 +02:00
apio
671f2a2de3 Kernel, libc: Implement waitpid() 
FIXME: exec() is now doing weird page table stuff. But at least it works, no panics :)
 2022-10-18 21:30:52 +02:00
apio
34fc6996b0 UserHeap: allocate needed memory in request_virtual_pages 2022-10-17 18:52:11 +02:00
apio
92634048fc UserHeap: some nice improvements 2022-10-17 18:49:19 +02:00
apio
64f5078494 Kernel, libc: Implement fork() 
This time for real.

Also, add a new per-user-task virtual address allocator (UserHeap), so that mmap'ed pages are in user range and can be copied.
 2022-10-17 18:43:35 +02:00
apio
b334e1cd50 VMM: check if the entry is already present 2022-10-17 17:26:16 +02:00
apio
682be58d97 AddressSpace: copy instead of linking 2022-10-17 17:24:33 +02:00
apio
68403dc029 Kernel: Make AddressSpaces reference-counted 2022-10-15 17:40:33 +02:00
apio
62d631f1b4 Kernel: Rename assert.h to kassert.h so IDEs pickup the kernel header instead of the userspace one 2022-10-15 12:56:48 +02:00
apio
e0aa552fae Kernel: Add a move() function 
The standard C++ move() function.
 2022-10-14 19:04:56 +02:00
apio
f82fbbe60c Make address spaces not cloned by default 2022-10-14 18:23:04 +02:00
apio
1c3377fc98 Prepare for cloning address spaces, not there yet 2022-10-14 18:17:57 +02:00
apio
e43777bd31 Apparently, it just works now. 2022-10-14 18:00:33 +02:00
apio
97a8a4a4a2 Solve rebase 2022-10-14 17:39:24 +02:00
apio
bb7887a29d Add basic address space infrastructure 2022-10-14 17:34:29 +02:00
apio
5abd8814e3 Kernel: Continue moving utilities to a separate subdirectory 2022-10-14 17:33:06 +02:00
apio
e21b608af4 Utilities: Start moving utilities into specific headers in a utils/ subdirectory 2022-10-14 17:31:47 +02:00
apio
26211bd49f It (almost) works now 
The only thing doing weird stuff is exec(), so that's commented out and throws ENOSYS right now.

But we have two user tasks running in parallel, isolated from each other!
 2022-10-14 16:46:00 +02:00
apio
24272c57ef Almost there! 2022-10-13 21:55:51 +02:00
apio
ee712432bd Some more multiple address space stuff 
This page-faults. This is because the memory where the ELF should be is all zeroes, which the CPU tries to interpret.
 2022-10-13 21:14:39 +02:00
apio
229b06c63b Add basic address space infrastructure 2022-10-13 19:19:51 +02:00
apio
83e6b8cd21 VMM: Fix naming convention 2022-10-13 18:42:53 +02:00
apio
57482e4e93 VMM: Make it even nicer 2022-10-13 18:15:52 +02:00
apio
b360307f41 VMM: Make it so much gooder 
There are still some fixes to be made, but I think this is already way cleaner than before.
 2022-10-13 17:58:13 +02:00
apio
52944ba5d8 Kernel/VMM: Add support for larger pages to getFlags() 2022-10-12 20:05:27 +02:00
apio
69a9f7f06a Kernel: Move VMM from a class to a namespace 
Also, rename the ugly Paging::VirtualMemoryManager name to just 'VMM'. Which is now used instead of kernelVMM.
 2022-10-12 20:02:25 +02:00
apio
3ac9fed23a ELFLoader: Add check_elf_image() and check_elf_image_from_filesystem() 
These two functions validate an image, without actually loading it. Very useful for exec!
 2022-10-12 18:37:00 +02:00
apio
bbd9f1d187 VMM: Add FIXME 2022-10-12 14:35:34 +02:00
apio
15f340dbbe VMM: Do not map recursively 2022-10-12 14:34:12 +02:00
apio
eaea4603c6 MemoryManager: Fix logging when built with debug logging 
That is to say, -DMM_DEBUG
 2022-10-12 14:29:30 +02:00
apio
4021cb3ac0 KernelHeap: do not crash the entire system 
Previously, calling free_virtual_page(s) would cause an assertion fail if the address was not in the kernel heap range.
Now, we just return.
 2022-10-12 14:28:48 +02:00
apio
ad9c7af0bf VMM: add FIXME 2022-10-12 14:27:47 +02:00
apio
950f4ef608 VMM: Add support for larger pages 
getPhysical() now stops at a larger page, unmap() can unmap a larger page, but map() just transforms it into a normal page.
getFlags() larger pages support is still pending.

At least now we don't page fault because we're trying to free a larger page.
 2022-10-12 14:27:26 +02:00
apio
525d567af6 VMM: When unmapping a page, invalidate the TLB for that page 2022-10-12 14:24:34 +02:00
apio
c9ebe89899 Kernel/KernelHeap: Add MODULE #define 2022-10-12 14:04:41 +02:00
apio
97eacc027e Kernel: Use PAGE_SIZE in more places 2022-10-12 13:05:57 +02:00
apio
d5f59b666a Kernel/Memory: Use %p in printf 2022-10-08 18:21:02 +02:00
apio
533b7c9e71 Refactor ACPI::get_rsdt_or_xsdt() 
Much better now.

Also, remove a FIXME in PMM.cpp, since we do map the page bitmap to virtual memory now.
 2022-10-08 15:00:42 +02:00
apio
abcf1b6118 Define PAGE_SIZE as 4096 and use it everywhere instead of using 4096 as a magic number 2022-10-08 14:52:28 +02:00
apio
028a1b1a3c libc: Enable even more warnings 2022-10-07 18:19:06 +02:00
apio
b7ee746da3 Kernel: Enable even more warnings 2022-10-07 18:10:20 +02:00
apio
594d79143e Kernel: enable -Wconversion 2022-10-06 17:13:34 +02:00
apio
952d8fa294 Be more strict with warnings 2022-10-05 17:34:22 +02:00
apio
8f310dd307 PMM: Map the page bitmap to kernel heap once the PMM and VMM are both initialized 2022-10-04 18:36:09 +02:00