Commit Graph

1542 Commits

Author SHA1 Message Date
Sergey Bugaev
e9dd94063f Kernel: Do not panic on fstat(fifo)
Instead, let's return an empty buffer with st_mode indicating it's a fifo.
2019-09-17 21:56:42 +02:00
Drew Stratford
6e51ebad8c Kernel: Stop hardcoding syscall in signal trampoline.
We now no longer hardcode the sigreturn syscall in
the signal trampoline. Because of the way inline asm inputs
work, I've had to enclose the trampoline in the function
signal_trampoline_dummy.
2019-09-17 16:00:37 +02:00
Conrad Pankoff
224fbb7910 Kernel: Fix returning pages to regions >= 2GB 2019-09-17 09:27:23 +02:00
Conrad Pankoff
9c5e3cd818 Kernel: Ignore memory the bootloader gives us above 2^32 2019-09-17 09:27:23 +02:00
Andreas Kling
a34f3a3729 Kernel: Fix some bitrot in MemoryManager debug logging code 2019-09-16 14:45:44 +02:00
Andreas Kling
5d491fa1cd Kernel: Add a simple slab allocator for small allocations
This is a freelist allocator with static size classes that works as a
complement to the generic kmalloc(). It's a lot faster than kmalloc()
since allocation just means popping from the freelist.

It's also significantly more compact when there are a lot of objects
smaller than the minimum kmalloc chunk size (32 bytes.)

This patch enables it for the Region and PhysicalPage classes.
In the PhysicalPage (8 bytes) case, it's a huge improvement since we
no longer waste 75% of the storage allocated.

There are also a number of ways this can be improved, so let's keep
working on it going forward.
2019-09-16 10:33:27 +02:00
Andreas Kling
1c692e87a6 Kernel: Move kmalloc() into a Kernel/Heap/ directory 2019-09-16 09:01:44 +02:00
Conrad Pankoff
6fd096999e Applications: Add "Welcome" application, inspired by Windows 98 2019-09-16 07:49:43 +02:00
Andreas Kling
e60bbadbbc Kernel: Add LogStream operator<< for PhysicalAddress 2019-09-15 20:47:49 +02:00
Andreas Kling
a40afc4562 Kernel: Get rid of MemoryManager::allocate_page_table()
We can just use the physical page allocator directly, there's no need
for a dedicated function for page tables.
2019-09-15 20:34:03 +02:00
Andreas Kling
85d629103d Kernel: Implement shebang executables ("#!/bin/sh")
This patch makes it possible to *run* text files that start with the
characters "#!" followed by an interpreter.

I've tested this with both the Serenity built-in shell and the Bash
shell, and it works as expected. :^)
2019-09-15 11:47:21 +02:00
Andreas Kling
e1481dcb42 Kernel: Stop idling after handling an IRQ
If we receive an IRQ while the idle task is running, prevent it from
re-halting the CPU after the IRQ handler returns.

Instead have the idle task yield to the scheduler, so we can see if
the IRQ has unblocked something.
2019-09-14 20:21:10 +02:00
Andreas Kling
b35ad5b523 Kernel: Fix bad assertion in Lock::unlock_if_locked()
We shouldn't assert if you call this on a Lock held by another Thread
in the same Process. Instead, we should just not unlock.
2019-09-14 20:21:06 +02:00
Drew Stratford
45ded86bcb Kernel: Move fchdir to end of enumerate syscalls.
The introduction fchdir in the middle of the EUMERATE_SYSCALLS
expression changed other syscall numbers, which broke compatibility.
This commit fixes that by moving it to the end.
2019-09-13 16:30:22 +02:00
Andreas Kling
2d1f3ec749 Kernel: fchdir() should fail for non-searchable directories
So sayeth POSIX.
2019-09-13 14:35:18 +02:00
Mauri de Souza Nunes
7d85fc00e4 Kernel: Implement fchdir syscall
The fchdir() function is equivalent to chdir() except that the
directory that is to be the new current working directory is
specified by a file descriptor.
2019-09-13 14:04:38 +02:00
Andreas Kling
b9be6b7bb4 Ext2FS: Trying to create a too-long directory entry should ENAMETOOLONG
Also added some assertions to DirectoryEntry in case someone tries to
instantiate them with names that would overflow the name buffer.

DirectoryEntry is a crappy data structure, and the name buffer is also
crappy. Added a FIXME about replacing it with something nicer.

Before this patch, the DirectoryEntry::name buffer would overflow if
you did "touch extremely-long-file-name". Duh.

Fixes #538.
2019-09-10 21:04:27 +02:00
Andreas Kling
b07cf6843e Runner: Forward host TCP port 8823 to guest port 23 in QEMU
This makes it easier to test TelnetServer when running in QEMU.
2019-09-09 09:19:43 +02:00
Andreas Kling
54caeb1f1a RTL8139: Fix bogus (but harmless) TX buffer index in send_raw()
This was getting fixed up by the loop that chooses the next TX buffer
anyway, but let's do this correctly.

Fixes #522.
2019-09-09 08:51:08 +02:00
Drew Stratford
b65bedd610 Kernel: Change m_blockers to m_blocker.
Because of the way signals now work there should
not be more than one blocker per thread. This
changes the blocker and thread class to reflect
that.
2019-09-09 08:35:43 +02:00
Drew Stratford
e529042895 Kernel: Remove reduntant kernel/user signal stacks.
Due to the changes in signal handling m_kernel_stack_for_signal_handler_region
and m_signal_stack_user_region are no longer necessary, and so, have been
removed. I've also removed the similarly reduntant m_tss_to_resume_kernel.
2019-09-09 08:35:43 +02:00
Conrad Pankoff
dfb538a413 Kernel: Write logs into dmesg from the start of the boot process 2019-09-09 08:14:00 +02:00
Andreas Kling
e386579436 Kernel: Fix bitrotted code behind #ifdef SIGNAL_DEBUG 2019-09-08 14:29:59 +02:00
Andreas Kling
23eafdb8d6 Kernel: waitpid() should unblock and -ECHILD if SIG_IGN reaps child 2019-09-08 14:01:00 +02:00
Conrad Pankoff
c983e96664 Kernel: Use timeval_sub for TCP retransmissions and lower timer to 500ms 2019-09-08 12:34:20 +02:00
Conrad Pankoff
3f1c3a341b Kernel: Handle listening socket disappearing during incoming handshake 2019-09-08 12:34:20 +02:00
Conrad Pankoff
feb6d1afe0 Kernel: Use a WeakPtr instead of a RefPtr for TCP socket originator 2019-09-08 12:34:20 +02:00
Conrad Pankoff
a2b61e30c5 Kernel: Put some network log messages behind debug flags 2019-09-08 12:34:20 +02:00
Conrad Pankoff
328d52b323 Kernel: Send ACK/FIN in response to FIN packets on active connections
This is to work around our lack of a shutdown() implementation.
2019-09-08 12:34:20 +02:00
Conrad Pankoff
117d8db2a2 Kernel: Implement outgoing TCP retransmission and better ACK handling
This approach is a bit naiive - whenever we send a packet out, we
check to see if there are any other packets we should try to send.
This works well enough for a busy connection but not very well for a
quiet one. Ideally we would check for not-acked packets on some kind
of timer, and use the length of this not-acked list as feedback to
throttle the writes coming from userspace.
2019-09-08 12:34:20 +02:00
Conrad Pankoff
b8e3c7ef01 Kernel: Remember all ARP replies, even ones we didn't request
This allows us to take advantage of unsolicited ARP replies, such as
those that are emitted by many systems after their network interfaces
are enabled, or after their DHCP client sets their IP.

This also makes us a bit more vulnerable to ARP flooding, but we need
some kind of eviction strategy anyway, so we can deal with that later.
2019-09-08 12:34:20 +02:00
Conrad Pankoff
b45cfae7f4 Kernel: Don't mark incoming sockets as connected in NetworkTask
An incoming socket should only be considered connected after a
program has received it from accept(). Before that point, it's only
"half" open, and it might not ever actually be served to a program.

Socket::accept is where m_connected is correctly set.
2019-09-08 12:34:20 +02:00
Conrad Pankoff
72f728b0d6 Kernel: Hold socket back from accept() until it's fully set up 2019-09-08 12:34:20 +02:00
Conrad Pankoff
d53c9d4416 Kernel: Use RefPtr instead of SocketHandle for TCPSocket clients
Using a SocketHandle takes a lock on the socket, which we don't want
to do.
2019-09-08 12:34:20 +02:00
Conrad Pankoff
cfcb53fe77 Kernel: Don't set sequence manually; send_tcp_packet will do it 2019-09-08 12:34:20 +02:00
Conrad Pankoff
e8a10848b5 Kernel: Make sure IPv4Socket is marked as listening in listen() 2019-09-08 12:34:20 +02:00
Conrad Pankoff
706e04d340 Kernel: Don't increment ACK number without SYN, FIN, or data 2019-09-08 12:34:20 +02:00
Conrad Pankoff
749719b4d0 Kernel: Fix debug messages in IPv4Socket 2019-09-08 12:34:20 +02:00
Conrad Pankoff
040947ee47 TelnetServer: Implement basic telnet server
Fixes #407

Depends on #530 to run reliably.
2019-09-08 10:56:34 +02:00
Andreas Kling
33e6cb8b80 Kernel: Remove spammy logging about absolute_path() on non-custodies 2019-09-08 09:37:28 +02:00
Andreas Kling
899233a925 Kernel: Handle running programs that don't have a TLS image
Programs without a PT_TLS header won't have a master TLS image for us
to copy, so we shouldn't try to copy the m_master_tls_region then.
2019-09-07 17:06:25 +02:00
Jesse Buhagiar
ecbc0322c1 Applications: Create a display properties manager
An interactive application to modify the current display settings, such as
the current wallpaper as well as the screen resolution. Currently we're
adding the resolutions ourselves, because there's currently no way to
detect was resolutions the current display adapter supports (or at least
I can't see one... Maybe VBE does and I'm stupid). It even comes with
a very nice template'd `ItemList` that can support a vector of any type,
which makes life much simpler.
2019-09-07 16:51:15 +02:00
Andreas Kling
ec6bceaa08 Kernel: Support thread-local storage
This patch adds support for TLS according to the x86 System V ABI.
Each thread gets a thread-specific memory region, and the GS segment
register always points _to a pointer_ to the thread-specific memory.

In other words, to access thread-local variables, userspace programs
start by dereferencing the pointer at [gs:0].

The Process keeps a master copy of the TLS segment that new threads
should use, and when a new thread is created, they get a copy of it.
It's basically whatever the PT_TLS program header in the ELF says.
2019-09-07 15:55:36 +02:00
Andreas Kling
73fdbba59c AK: Rename <AK/AKString.h> to <AK/String.h>
This was a workaround to be able to build on case-insensitive file
systems where it might get confused about <string.h> vs <String.h>.

Let's just not support building that way, so String.h can have an
objectively nicer name. :^)
2019-09-06 15:36:54 +02:00
Drew Stratford
95fe775d81 Kernel: Add SysV stack alignment to signal trampoline
In both dispatch signal and asm_signal_trampoline we
now ensure that the stack is 16 byte aligned, as per
the System V ABI.
2019-09-05 16:37:09 +02:00
Drew Stratford
81d0f96f20 Kernel: Use user stack for signal handlers.
This commit drastically changes how signals are handled.

In the case that an unblocked thread is signaled it works much
in the same way as previously. However, when a blocking syscall
is interrupted, we set up the signal trampoline on the user
stack, complete the blocking syscall, return down the kernel
stack and then jump to the handler. This means that from the
kernel stack's perspective, we only ever get one system call deep.

The signal trampoline has also been changed in order to properly
store the return value from system calls. This is necessary due
to the new way we exit from signaled system calls.
2019-09-05 16:37:09 +02:00
Drew Stratford
259a1d56b0 Thread: added member m_kernel_stack_top.
This value stores the top of a threads kernel_stack.
2019-09-05 16:37:09 +02:00
Andreas Kling
bf43d94a2f Kernel: Disable interrupts throughout ~Region()
We don't want an interrupt handler to access the VM data structures
while their internal consistency is broken.
2019-09-05 11:15:05 +02:00
Andreas Kling
1188a036e9 SoundPlayer: Start working on a GUI sound player application
This can play anything that AWavLoader can load (so obviously only WAV
files at the moment.)

It works by having a timer that wakes up every 100ms and tries to send
a sample buffer to the AudioServer. If our server-side queue is full
then we wait until the next timer iteration and try again.

We display the most recently enqueued sample buffer in a nice little
widget that just plots the samples in green-on-black. :^)
2019-09-04 20:18:41 +02:00
Andreas Kling
e25ade7579 Kernel: Rename "vmo" to "vmobject" everywhere 2019-09-04 11:27:14 +02:00