Commit graph

45 commits

Author SHA1 Message Date
Andreas Kling
19d3f8cab7 Kernel+LibC: Turn errno codes into a strongly typed enum
..and allow implicit creation of KResult and KResultOr from ErrnoCode.
This means that kernel functions that return those types can finally
do "return EINVAL;" and it will just work.

There's a handful of functions that still deal with signed integers
that should be converted to return KResults.
2021-01-20 23:20:02 +01:00
Ben Wiederhake
64cc3f51d0 Meta+Kernel: Make clang-format-10 clean 2020-09-25 21:18:17 +02:00
Tom
c8d9f1b9c9 Kernel: Make copy_to/from_user safe and remove unnecessary checks
Since the CPU already does almost all necessary validation steps
for us, we don't really need to attempt to do this. Doing it
ourselves doesn't really work very reliably, because we'd have to
account for other processors modifying virtual memory, and we'd
have to account for e.g. pages not being able to be allocated
due to insufficient resources.

So change the copy_to/from_user (and associated helper functions)
to use the new safe_memcpy, which will return whether it succeeded
or not. The only manual validation step needed (which the CPU
can't perform for us) is making sure the pointers provided by user
mode aren't pointing to kernel mappings.

To make it easier to read/write from/to either kernel or user mode
data add the UserOrKernelBuffer helper class, which will internally
either use copy_from/to_user or directly memcpy, or pass the data
through directly using a temporary buffer on the stack.

Last but not least we need to keep syscall params trivial as we
need to copy them from/to user mode using copy_from/to_user.
2020-09-13 21:19:15 +02:00
Tom
d89582880e Kernel: Switch singletons to use new Singleton class
MemoryManager cannot use the Singleton class because
MemoryManager::initialize is called before the global constructors
are run. That caused the Singleton to be re-initialized, causing
it to create another MemoryManager instance.

Fixes #3226
2020-08-25 09:48:48 +02:00
Andreas Kling
2fd9e72264 Revert "Kernel: Switch singletons to use new Singleton class"
This reverts commit f48feae0b2.
2020-08-22 18:01:59 +02:00
Andreas Kling
8925ad3fa0 Revert "Kernel: Move Singleton class to AK"
This reverts commit f0906250a1.
2020-08-22 16:34:49 +02:00
Andreas Kling
68580d5a8d Revert "AK: Get rid of make_singleton function"
This reverts commit 5a98e329d1.
2020-08-22 16:34:14 +02:00
Tom
5a98e329d1 AK: Get rid of make_singleton function
Just default the InitFunction template argument.
2020-08-22 10:46:24 +02:00
Tom
f0906250a1 Kernel: Move Singleton class to AK 2020-08-22 10:46:24 +02:00
Tom
f48feae0b2 Kernel: Switch singletons to use new Singleton class
Fixes #3226
2020-08-21 11:47:35 +02:00
Andreas Kling
7a3ab6c517 Kernel: Make File::write() and File::read() return KResultOr<size_t>
Instead of returning a ssize_t where negative values mean error,
we now return KResultOr<size_t> and use the error state to report
errors exclusively.
2020-08-04 18:17:16 +02:00
Tom
d249b5df8f Kernel: Protect Console with SpinLock 2020-07-01 12:07:01 +02:00
Sergey Bugaev
f11270e7ce Kernel: Port VirtualConsole to LibVT :^)
Unfortunately this drops the feature of preserving VGA buffer contents.

Resolves https://github.com/SerenityOS/serenity/issues/2399
2020-05-27 11:19:38 +02:00
Andreas Kling
21d5f4ada1 Kernel: Absorb LibBareMetal back into the kernel
This was supposed to be the foundation for some kind of pre-kernel
environment, but nobody is working on it right now, so let's move
everything back into the kernel and remove all the confusion.
2020-05-16 12:00:04 +02:00
Liav A
e559af2008 Kernel: Apply changes to use LibBareMetal definitions 2020-02-09 19:38:17 +01:00
Andreas Kling
94ca55cefd Meta: Add license header to source files
As suggested by Joshua, this commit adds the 2-clause BSD license as a
comment block to the top of every source file.

For the first pass, I've just added myself for simplicity. I encourage
everyone to add themselves as copyright holders of any file they've
added or modified in some significant way. If I've added myself in
error somewhere, feel free to replace it with the appropriate copyright
holder instead.

Going forward, all new source files should include a license header.
2020-01-18 09:45:54 +01:00
Andreas Kling
1b2ef8582c Kernel: Make File's can_read/can_write take a const FileDescription&
Asking a File if we could possibly read or write it will never mutate
the asking FileDescription&, so it should be const.
2019-11-04 14:03:14 +01:00
Nicolas Van Bossuyt
81c4dcadf1 Kernel: Prevent kprintf() from asserting in Console::the() (#718)
This triggered a stack overflow because ubsan can call kprintf() at any
time, even before Console is initialized.
2019-11-03 13:17:55 +01:00
Andreas Kling
27f699ef0c AK: Rename the common integer typedefs to make it obvious what they are.
These types can be picked up by including <AK/Types.h>:

* u8, u16, u32, u64 (unsigned)
* i8, i16, i32, i64 (signed)
2019-07-03 21:20:13 +02:00
Andreas Kling
08cd75ac4b Kernel: Rename FileDescriptor to FileDescription.
After reading a bunch of POSIX specs, I've learned that a file descriptor
is the number that refers to a file description, not the description itself.
So this patch renames FileDescriptor to FileDescription, and Process now has
FileDescription* file_description(int fd).
2019-06-07 09:36:51 +02:00
Andreas Kling
8cbb7f101f Kernel: Have File virtuals take a FileDescriptor& rather than a Process&.
This will allow us to implement different behaviors depending on the role
of the descriptor a File is being accessed through.
2019-04-29 13:58:40 +02:00
Andreas Kling
0bc72551f4 Kernel: Remove two unneeded headers. 2019-04-10 22:49:11 +02:00
Andreas Kling
beda478821 Kernel: Make syscalls that take a buffer size use ssize_t instead of size_t.
Dealing with the unsigned overflow propagation here just seems unreasonably
error prone. Let's limit ourselves to 2GB buffer sizes instead.
2019-02-25 21:21:12 +01:00
Andreas Kling
7455f5ea42 Expose the kernel log buffer through /proc/dmesg.
Also add a /bin/dmesg program for convenience.
2019-01-28 22:40:55 +01:00
Andreas Kling
bd3e77cc16 Pass the process to CharacterDevice::read/write.
This is much nicer than grabbing directly at 'current' inside a read().
2019-01-16 00:20:38 +01:00
Andreas Kling
08bfe518f9 Rename CharacterDevice::has_data_available_for_reading() -> can_read(). 2019-01-16 00:10:13 +01:00
Andreas Kling
b0e3f73375 Start refactoring the windowing system to use an event loop.
Userspace programs can now open /dev/gui_events and read a stream of GUI_Event
structs one at a time.

I was stuck on a stupid problem where we'd reenter Scheduler::yield() due to
having one of the has_data_available_for_reading() implementations using locks.
2019-01-14 14:42:49 +01:00
Andreas Kling
aff89d2fd7 Yet more coding style fixes. 2018-12-03 01:38:22 +01:00
Andreas Kling
f6e27c2abe More coding style changes. 2018-12-03 00:39:25 +01:00
Andreas Kling
f1404aa948 Add primitive FIFO and hook it up to sys$pipe().
It's now possible to do this in bash:

cat kernel.map | fgrep List

This is very cool! :^)
2018-11-12 01:28:46 +01:00
Andreas Kling
2ac5e14c08 Merge VGA into VirtualConsole. 2018-11-10 16:26:18 +01:00
Andreas Kling
b833aa4162 Fix bug where Console::the() was initialized too late.
Yet another problem due to lack of BSS zeroing in the kernel loader...
2018-10-30 23:02:06 +01:00
Andreas Kling
68739dc43e Start working on virtual consoles/TTYs.
This is a mess right now, but I'd rather commit as I go.
2018-10-30 13:59:29 +01:00
Andreas Kling
bd2b5327d0 Basic support the backspace key.
This doesn't mean we get any line editing just yet. But the keyboard device
now recognizes the backspace key, and the console device knows what to do
with the backspace characters.
2018-10-30 11:55:58 +01:00
Andreas Kling
e6284a8774 Fix broken SpinLock.
The SpinLock was all backwards and didn't actually work. Fixing it exposed
how wrong most of the locking here is.

I need to come up with a better granularity here.
2018-10-29 22:04:26 +01:00
Andreas Kling
43475f248b Add save/unsave cursor escape sequences.
Also added a little terminal test program called /bin/tst.
2018-10-28 01:44:53 +02:00
Andreas Kling
dd3244137e Add basic support for ANSI color escape sequences. 2018-10-28 00:56:19 +02:00
Andreas Kling
8289a5c93c Implement 'H' and 'J' escape sequences. 2018-10-27 23:42:20 +02:00
Andreas Kling
546ddd7de0 Remove logspam in /dev/{full,null,zero} now that they work just fine.
Also don't echo anything to console when putch'ing '\0'.
2018-10-26 11:27:42 +02:00
Andreas Kling
c6f2890d8e Implement a basic way for read() to block.
FileHandle gets a hasDataAvailableForRead() getter.
If this returns true in sys$read(), the task will block(BlockedRead) + yield.
The fd blocked on is stored in Task::m_fdBlockedOnRead.
The scheduler then looks at the state of that fd during the unblock phase.

This makes "sh" restful. :^)

There's still some problem with the kernel not surviving the colonel task
getting scheduled. I need to figure that out and fix it.
2018-10-25 13:09:56 +02:00
Andreas Kling
3676214a62 Remove remains of the old "panel" task.
...and grow the console by 1 row! :^)
2018-10-23 15:47:03 +02:00
Andreas Kling
77821da42f Also send console output to port 0xe9 (bochs console.)
This is very handy for debugging.
2018-10-23 13:02:38 +02:00
Andreas Kling
79ffdb7205 A lot of hacking:
- More work on funneling console output through Console.
- init() now breaks off into a separate task ASAP.
- ..this leaves the "colonel" task as a simple hlt idle loop.
- Mask all IRQs on startup (except IRQ2 for slave passthru)
- Fix underallocation bug in Task::allocateRegion().
- Remember how many times each Task has been scheduled.

The panel and scheduling banner are disabled until I get things
working nicely in the (brave) new Console world.
2018-10-22 11:15:16 +02:00
Andreas Kling
fc88368582 Have Console::write() directly call vga_putch. 2018-10-21 22:44:26 +02:00
Andreas Kling
a70bfb87d5 Add a Console device and start refactoring screen output. 2018-10-21 21:59:43 +02:00