kmi/src/uapi/mem.c, branch masterACTIVE - Kernel with migrating threads as IPChttps://metanimi.dy.fi/cgit/kmi/atom?h=master2026-01-25T15:14:53Zimplement dmem semi-properly2026-01-25T15:14:53ZKimplulkimi.h.kuparinen@gmail.com2026-01-25T15:14:53Zurn:sha1:cd41ed1758f4842d7b78870385e16b579cc89c38
+ Add tests and fix virtual mapping, this is enough to start writing
proper userspace drivers
specify some error codes2026-01-24T21:27:28ZKimplulkimi.h.kuparinen@gmail.com2026-01-24T21:27:28Zurn:sha1:783e615ca031045eaa979532fc2c2b762ed8593fmake physical memory request a capability2026-01-24T21:24:45ZKimplulkimi.h.kuparinen@gmail.com2026-01-24T21:24:45Zurn:sha1:6fb77c70559782a9928432af5cc6f83906a530c1
+ Seems obvious, not sure why I hadn't done it already
improvements to shared memory handling2024-08-30T16:20:21ZKimplulkimi.h.kuparinen@gmail.com2024-08-30T16:20:21Zurn:sha1:314bca3dc19a864c76153bfcd5a58be8c40000f9
+ Now each shared region is reference counter (technically each region
is refernce counted, private regions just have a count of 1).
Also, syscalls that touch the TLB get flushed, but should probably
look into where else this flushing might be needed.
fix make clean2024-07-09T19:25:07ZKimplulkimi.h.kuparinen@gmail.com2024-07-09T19:25:07Zurn:sha1:0c6ba17b2f08d05195cdbaeba4607fdd8d000775start working on tests2024-07-09T19:12:27ZKimplulkimi.h.kuparinen@gmail.com2024-07-09T19:12:27Zurn:sha1:e8a1df103cc28419dd7d4439c0b1d1739d110f78
+ Current setup will likely not last long, just a stopgap until I figure
out how I want to build each testcase etc.
Probably dir based, but I'll probably add some scripts that generate
the build rules for each test case (or binary?). Also, should probably
put ouput files in a build directory and keep the source clean, but
again, good enough for now.
Will have to start implementing more extensive tests, and probably
come up with some way to compare textual output etc.
allow mapping null page2024-07-09T14:35:56ZKimplulkimi.h.kuparinen@gmail.com2024-07-09T14:35:56Zurn:sha1:298636079d912d0936f8156a609fe74b839c547b
+ User has to 'free' the 0 page before it becomes accessible to mapping.
Probably worth noting that this is likely VERY niche and mainly
concerns stuff like certain kinds of emulators that I'm still
eons from implementing, but still.
Unbacked pages can also be useful for some kinds of notifications,
like 'if someone writes to this page, please report it to me with this
ID' or whatever, I remember seeing some discussion about it somewhere
but that's also not really relevant for the moment.
Most significantly, at least with the current design,
after the null page is freed it becomes available for use to regular req_mem()
calls, so users should probably using locks around memory requests.
That's probably a good idea anyway as internally the kernal has to
lock the virtual memory, and without a scheduler it might cause
threads to spin for a while in the kernel which is rather bad.
add req_page back in as I realized it's useful2024-07-07T18:47:14ZKimplulkimi.h.kuparinen@gmail.com2024-07-07T18:47:14Zurn:sha1:219c27d420fe0abe5515cefc2513c6fe60aafdf9
+ Can be used to pass contiguous memory regions to things like virtio
block devices for implementing disk drivers etc.
make dmem a bit more readable2024-07-06T17:29:49ZKimplulkimi.h.kuparinen@gmail.com2024-07-06T17:29:49Zurn:sha1:e9da1d29939a74e186afc39f2fce8e085764fea0pretty massive virtual memory rewrite2024-07-06T15:14:04ZKimplulkimi.h.kuparinen@gmail.com2024-07-06T15:14:04Zurn:sha1:76517486919657ecadda9867125dc6730f29a5b7
+ The system is now a bit simpler and hopefully easier to understand, while also
extending the shared memory to be 1:N, where there is one owner who
may become a zombie while waiting for the N to die.