Unlike accept() the new accept4() system call lets the caller specify
flags for the newly accepted socket file descriptor, such as
SOCK_CLOEXEC and SOCK_NONBLOCK.
This commit adds support for the various ECHO* lflags and fixes some
POSIX conformance issues around newline handling. Also included are
error messages when setting not implemented settings.
Because we don't parse ACPI AML yet, If we are not able to shut down
the machine with "hacky" emulation methods - halt and print this state
to the users so they know they can shutdown the machine by themselves.
This fixes a bug that was reported on this discord server by
@ElectrodeYT - due to the confusion of passing arguments in different
orders, we messed up and triggered a page fault due to faulty sizes.
If we create a VGACompatibleAdapter object with a preset framebuffer,
Always assign the console so we can use it.
This is useful for modesetting done by a Multiboot loader, like GRUB.
As we removed the support of VBE modesetting that was done by GRUB early
on boot, we need to determine if we can modeset the resolution with our
drivers, and if not, we should enable text mode and ensure that
SystemServer knows about it too.
Also, SystemServer should first check if there's a framebuffer device
node, which is an indication that text mode was not even if it was
requested. Then, if it doesn't find it, it should check what boot_mode
argument the user specified (in case it's self-test). This way if we
try to use bochs-display device (which is not VGA compatible) and
request a text mode, it will not honor the request and will continue
with graphical mode.
Also try to print critical messages with mininum memory allocations
possible.
In LibVT, We make the implementation flexible for kernel-specific
methods that are implemented in ConsoleImpl class.
We used GRUB to modeset the resolution for a long time, but for good
reasons I see no point with keeping it supported in our kernel. We
support bochs-display device on QEMU (both the VGA compatible and
non-VGA compatible variants), so for QEMU we can still boot the system
in graphical mode even without GRUB help.
Also, we now have a native driver for Intel graphics and although it
doesn't support most Intel graphics cards out there yet, it's a good
starting point to support more cards. If a user wants to boot on
bare-metal in graphical mode, all he needs to do is to add the removed
flag back again, as the kernel still supports pre-set framebuffers.
This new subsystem is replacing the old code that was used to
create device nodes of framebuffer devices in /dev.
This subsystem includes for now 3 roles:
1. GraphicsManagement singleton object that is used in the boot
process to enumerate and initialize display devices.
2. GraphicsDevice(s) that are used to control the display adapter.
3. FramebufferDevice(s) that are used to control the device node in
/dev.
For now, we support the Bochs display adapter and any other
generic VGA compatible adapter that was configured by the boot
loader to a known and fixed resolution.
Two improvements in the Bochs display adapter code are that
we can support native bochs-display device (this device doesn't
expose any VGA capabilities) and also that we use the MMIO region,
to configure the device, instead of setting IO ports for such tasks.
This device is a graphics display device that is not supporting
VGA functionality.
Therefore, it exposes a MMIO region to configure it, so we use that
region to set the framebuffer resolution.
Previously ByteBuffer would internally hold a RefPtr to the byte
buffer and would behave like a reference type, i.e. copying a
ByteBuffer would not create a duplicate byte buffer, but rather
two objects which refer to the same internal buffer.
This also changes ByteBuffer so that it has some internal capacity
much like the Vector<T> type. Unlike Vector<T> however a byte
buffer's data may be uninitialized.
With this commit ByteBuffer makes use of the kmalloc_good_size()
API to pick an optimal allocation size for its internal buffer.
This non-POSIX header is used in Linux/BSD systems for storing the
default termios settings. This lets us setup new TTYs' `m_termios.c_cc`
in a nicer way than using a magic string.
This commit replaces the former, hand-written parser with a new one that
can be generated automatically according to a state change diagram.
The new `EscapeSequenceParser` class provides a more ergonomic interface
to dealing with escape sequences. This interface has been inspired by
Alacritty's [vte library](https://github.com/alacritty/vte/).
I tried to avoid changing the application logic inside the `Terminal`
class. While this code has not been thoroughly tested, I can't find
regressions in the basic command line utilities or `vttest`.
`Terminal` now displays nicer debug messages when it encounters an
unknown escape sequence. Defensive programming and bounds checks have
been added where we access parameters, and as a result, we can now
endure 4-5 seconds of `cat /dev/urandom`. :D
We generate EscapeSequenceStateMachine.h when building the in-kernel
LibVT, and we assume that the file is already in place when the userland
library is being built. This will probably cause problems later on, but
I can't find a way to do it nicely.
By constraining two implementations, the compiler will select the best
fitting one. All this will require is duplicating the implementation and
simplifying for the `void` case.
This constraining also informs both the caller and compiler by passing
the callback parameter types as part of the constraint
(e.g.: `IterationFunction<int>`).
Some `for_each` functions in LibELF only take functions which return
`void`. This is a minimal correctness check, as it removes one way for a
function to incompletely do something.
There seems to be a possible idiom where inside a lambda, a `return;` is
the same as `continue;` in a for-loop.
Regressed in 8a4cc735b9.
We stopped generating "process created" when enabling profiling,
which led to Profiler getting confused about the missing events.
Fixes off-by-one caused by reading the register directly
without adding a 1 to it, because AHCI reports 1 less port than
the actual number of ports supported.
This implements the macOS API malloc_good_size() which returns the
true allocation size for a given requested allocation size. This
allows us to make use of all the available memory in a malloc chunk.
For example, for a malloc request of 35 bytes our malloc would
internally use a chunk of size 64, however the remaining 29 bytes
would be unused.
Knowing the true allocation size allows us to request more usable
memory that would otherwise be wasted and make that available for
Vector, HashTable and potentially other callers in the future.
Previously calls to perf_event() would end up in a process-specific
perfcore file even though global profiling was enabled. This changes
the behavior for perf_event() so that these events are stored into
the global profile instead.
On my machine, it only sets PRC and not PCC.
Confirmed to happen on:
- 8086:9ca2 (Intel Corporation Wildcat Point-LP SATA Controller
[AHCI Mode] (rev 03))
On my bare metal machine, enabling it as this point causes it to
instantly send an interrupt, and we're too early in the process
to be able to handle AHCI interrupts. The interrupts were being
enabled in the initialize function anyway.
Confirmed to happen on:
- 8086:9ca2 (Intel Corporation Wildcat Point-LP SATA Controller
[AHCI Mode] (rev 03))
- 8086:3b22 (Intel Corporation 5 Series/3400 Series Chipset
6 port SATA AHCI Controller (rev 06))
Occasionally we'll see messages in the serial console like:
handle_tcp: unexpected flags in FinWait1 state
In these cases it would be nice to know what flags we are receiving that
we aren't expecting.
The following KUBSAN crash on startup was reported on discord:
```
UHCI: Started
KUBSAN: reference binding to null pointer of type struct UHCIController
KUBSAN: at ../../Kernel/Devices/USB/UHCIController.cpp, line 67
```
After inspecting the code, it became clear that there's a window of time
where the kernel task which monitors the UHCI port can startup and start
executing before the UHCIController constructor completes. This leaves
the singleton pointing to nullptr, thus in the duration of this race
window the "UHCI port proc" thread will go an and de-reference the null
pointer when trying to read for status changes on the UHCI root ports.
Reported-by: @stelar7
Reported-by: @bcoles
Fixes: #6154
AnonymousVMObject::create_with_physical_page(s) can't be NonnullRefPtr
as it allocates internally. Fixing the API then surfaced an issue in
ScatterGatherList, where the code was attempting to create an
AnonymousVMObject in the constructor which will not be observable
during OOM.
Fix all of these issues and start propagating errors at the callers
of the AnonymousVMObject and ScatterGatherList APis.
This change looks more involved than it actually is. This simply
reshuffles the previous Process constructor and splits out the
parts which can fail (resource allocation) into separate methods
which can be called from a factory method. The factory is then
used everywhere instead of the constructor.
This code was unlocking the lock directly, but the Locker is still
attached, causing the lock to be unlocked an extra time, hence
corrupting the internal lock state.
This is extra confusing though, as complete_current_request() runs
without a lock which also looks like a bug. But that's a task for
another day.
The separate backtrace that the PANIC emits isn't useful and just adds
more data to visually filter from the output when debugging an issue.
Instead of calling PANIC, just emit the message with dbgln() and
manually halt the system.
If we are attempting to emit debugging information about an unhandleable
page fault, don't crash trying to kill threads or dump processes if the
current_thread isn't set in TLS. Attempt to keep proceeding in order to
dump as much useful information as possible.
Related: #6948
We were using ELF::Image::section(0) to indicate the "undefined"
section, when what we really wanted was just Optional<Section>.
So let's use Optional instead. :^)
The function fstatat can do the same thing as the stat and lstat
functions. However, it can be passed the file descriptor of a directory
which will be used when as the starting point for relative paths. This
is contrary to stat and lstat which use the current working directory as
the starting for relative paths.
Previously we didn't retransmit lost TCP packets which would cause
connections to hang if packets were lost. Also we now time out
TCP connections after a number of retransmission attempts.
This wakes up NetworkTask every 500 milliseconds so that it can send
pending delayed TCP ACKs and isn't forced to send all of them early
when it goes to sleep like it did before.
When establishing the connection we should send ACKs right away so
as to not delay the connection process. This didn't previously
matter because we'd flush all delayed ACKs when NetworkTask waits
for incoming packets.
Ideally we would never allocate under a spinlock, as it has many
performance and potentially functionality (deadlock) pitfalls.
We violate that rule in many places today, but we need a tool to track
them all down and fix them. This change introduces a new macro option
named `KMALLOC_VERIFY_NO_SPINLOCK_HELD` which can catch these
situations at runtime via an assert.
Avoid holding the sockets_by_tuple lock while allocating the TCPSocket.
While checking if the list contains the item we can also hold the lock
in shared mode, as we are only reading the hash table.
In addition the call to from_tuple appears to be superfluous, as we
created the socket, so we should be able to just return it directly.
This avoids the recursive lock acquisition, as well as the unnecessary
hash table lookups.
This ensures that the lost_samples field is set to zero for the
first sample. We didn't lose any samples before the first sample
so this is the correct value. Without this Profiler gets confused
and draws the graph for the process which contains the first CPU
sample incorrectly (all zeroes usually).
We can lose profiling timer events for a few reasons, for example
disabled interrupts or system slowness. This accounts for lost
time between CPU samples by adding a field lost_samples to each
profiling event which tracks how many samples were lost immediately
preceding the event.
This updates the profiling subsystem to use a separate timer to
trigger CPU sampling. This timer has a higher resolution (1000Hz)
and is independent from the scheduler. At a later time the
resolution could even be made configurable with an argument for
sys$profiling_enable() - but not today.
Make messages which should be fatal, actually fail the build.
- FATAL is not a valid mode keyword. The full list is available in the
docs: https://cmake.org/cmake/help/v3.19/command/message.html
- SEND_ERROR doesn't immediately stop processing, FATAL_ERROR does.
We should immediately stop if the Toolchain is not present.
- The app icon size validation was just a WARNING that is easy to
overlook. We should promote it to a FATAL_ERROR so that people will
not overlook the issue when adding a new application. We can only make
the small icon message FATAL_ERROR, as there is currently one
violation of the medium app icon validation.
Note that the changes to IPv4Socket::create are unfortunately needed as
the return type of TCPSocket::create and IPv4Socket::create don't match.
- KResultOr<NonnullRefPtr<TcpSocket>>>
vs
- KResultOr<NonnullRefPtr<Socket>>>
To handle this we are forced to manually decompose the KResultOr<T> and
return the value() and error() separately.
The make<T> factory function allocates internally and immediately
dereferences the pointer, and always returns a NonnullOwnPtr<T> making
it impossible to propagate an error on OOM.
The make<T> factory function allocates internally and immediately
dereferences the pointer, and always returns a NonnullOwnPtr<T> making
it impossible to propagate an error on OOM.
Modify the API so it's possible to propagate error on OOM failure.
NonnullOwnPtr<T> is not appropriate for the ThreadTracer::create() API,
so switch to OwnPtr<T>, use adopt_own_if_nonnull() to handle creation.
Currently, when passing buffers into VirtIOQueues, we use scatter-gather
lists, which contain an internal vector of buffers. This vector is
allocated, filled and the destroy whenever we try to provide buffers
into a virtqueue, which would happen a lot in performance cricital code
(the main transport mechanism for certain paravirtualized devices).
This commit moves it over to using VirtIOQueueChains and building the
chain in place in the VirtIOQueue. Also included are a bunch of fixups
for the VirtIO Console device, making it use an internal VM::RingBuffer
instead.
We want to move this out of the AHCI subsystem into the VM system,
since other parts of the kernel may need to perform scatter-gather IO.
We rename the current VM::ScatterGatherList impl that's used in the
virtio subsystem to VM::ScatterGatherRefList, since its distinguishing
feature from the AHCI scatter-gather list is that it doesn't own its
buffers.
For Kernel OOM hardening to work correctly, we need to be able to
call a "nothrow" version of operator new. Unfortunately the default
"throwing" version of operator new assumes that the allocation will
never return on failure and will always throw an exception. This isn't
true in the Kernel, as we don't have exceptions. So if we call the
normal/throwing new and kmalloc returns NULL, the generated code will
happily go and dereference that NULL pointer by invoking the constructor
before we have a chance to handle the failure.
To fix this we declare operator new as noexcept in the Kernel headers,
which will allow the caller to actually handle allocation failure.
The delete implementations need to match the prototype of the new which
allocated them, so we need define delete as noexcept as well. GCC then
errors out declaring that you should implement sized delete as well, so
this change provides those stubs in order to compile cleanly.
Finally the new operator definitions have been standardized as being
declared with [[nodiscard]] to avoid potential memory leaks. So lets
declares the kernel versions that way as well.
This avoids some of the the shortest-lived allocations in the kernel:
StringImpl::create_uninitialized(unsigned long, char*&)
StringImpl::create(char const*, unsigned long, ShouldChomp)
StringBuilder::to_string() const
String::vformatted(StringView, TypeErasedFormatParams)
void Kernel::KBufferBuilder::appendff<unsigned int>(...)
JsonObjectSerializer<Kernel::KBufferBuilder>::add(..., unsigned int)
Kernel::procfs$all(Kernel::InodeIdentifier, ...) const
Kernel::procfs$all(Kernel::InodeIdentifier, Kernel::KBufferBuilder&)
This avoids allocations for initializing the Function<T>
for the NetworkAdapter::for_each callback argument.
Applying this patch decreases CPU utilization for NetworkTask
from 40% to 28% when receiving TCP packets at a rate of 100Mbit/s.
We already have another limit for the total number of packet buffers
allowed (max_packet_buffers). This second limit caused us to
repeatedly allocate and then free buffers.
This patch modifies InodeWatcher to switch to a one watcher, multiple
watches architecture. The following changes have been made:
- The watch_file syscall is removed, and in its place the
create_iwatcher, iwatcher_add_watch and iwatcher_remove_watch calls
have been added.
- InodeWatcher now holds multiple WatchDescriptions for each file that
is being watched.
- The InodeWatcher file descriptor can be read from to receive events on
all watched files.
Co-authored-by: Gunnar Beutner <gunnar@beutner.name>
If the HPET main counter does not support full 64 bits, we should
not expect the upper 32 bit to work. This is a problem when writing
to the upper 32 bit of the comparator value, which requires the
TimerConfiguration::ValueSet bit to be set, but if it's not 64 bit
capable then the bit will not be cleared and leave it in a bad state.
Fixes#6990
This matches what other operating systems like Linux do:
$ ip route get 0.0.0.0
local 0.0.0.0 dev lo src 127.0.0.1 uid 1000
cache <local>
$ ssh 0.0.0.0
gunnar@0.0.0.0's password:
$ ss -na | grep :22 | grep ESTAB
tcp ESTAB 0 0 127.0.0.1:43118 127.0.0.1:22
tcp ESTAB 0 0 127.0.0.1:22 127.0.0.1:43118
When we receive a TCP packet with a sequence number that is not what
we expected we have lost one or more packets. We can signal this to
the sender by sending a TCP ACK with the previous ack number so that
they can resend the missing TCP fragments.
Previously we'd process TCP packets in whatever order we received
them in. In the case where packets arrived out of order we'd end
up passing garbage to the userspace process.
This was most evident for TLS connections:
courage:~ $ git clone https://github.com/SerenityOS/serenity
Cloning into 'serenity'...
remote: Enumerating objects: 178826, done.
remote: Counting objects: 100% (1880/1880), done.
remote: Compressing objects: 100% (907/907), done.
error: RPC failed; curl 56 OpenSSL SSL_read: error:1408F119:SSL
routines:SSL3_GET_RECORD:decryption failed or bad record mac, errno 0
error: 1918 bytes of body are still expected
fetch-pack: unexpected disconnect while reading sideband packet
fatal: early EOF
fatal: fetch-pack: invalid index-pack output
When the MSS option header is missing the default maximum segment
size is 536 which results in lots of very small TCP packets that
NetworkTask has to handle.
This adds the MSS option header to outbound TCP SYN packets and
sets it to an appropriate value depending on the interface's MTU.
Note that we do not currently do path MTU discovery so this could
cause problems when hops don't fragment packets properly.
This increases the default TCP window size to a more reasonable
value of 64k. This allows TCP peers to send us more packets before
waiting for corresponding ACKs.
This increases the buffer size for connection-oriented sockets
to 256kB. In combination with the other patches in this series
I was able to receive TCP packets at a rate of about 120Mbps.
The get_dir_entries syscall failed if the serialized form of all the
directory entries together was too large to fit in its temporary buffer.
Now the kernel uses a fixed size buffer, that is flushed to an output
buffer when it is full. If this flushing operation fails because there
is not enough space available, the syscall will return -EINVAL. That
error code is then used in userspace as a signal to allocate a larger
buffer and retry the syscall.
Previously we'd try to load ELF images which did not have
an interpreter set with an incorrect load offset of 0, i.e. way
outside of the part of the address space where we'd expect either
the dynamic loader or the user's executable to reside.
This fixes the problem by using get_load_offset for both executables
which have an interpreter set and those which don't. Notably this
allows us to actually successfully execute the Loader.so binary:
courage:~ $ /usr/lib/Loader.so
You have invoked `Loader.so'. This is the helper program for programs
that use shared libraries. Special directives embedded in executables
tell the kernel to load this program.
This helper program loads the shared libraries needed by the program,
prepares the program to run, and runs it. You do not need to invoke
this helper program directly.
courage:~ $
Previously we'd incorrectly use the default gateway's MAC address.
Instead we must use destination MAC addresses that are derived from
the multicast IPv4 address.
With this patch applied I can query mDNS on a real network.
The Kernel/.gitignore file is a remnant of the prior build system,
where the kernel.map was written directly to to the Kernel folder.
The run.sh was also under Kernel so pcap files and others would get
dropped there when running the system under qemu.
None of these situations are possible now, so lets get rid of it.
Instead of reading in the entire contents of a directory into a large
buffer, we can iterate block by block. This only requires a small
buffer.
Because directory entries are guaranteed to never span multiple blocks
we do not have to handle any edge cases related to that.
On some cases, the FADT could be on the end of a page, so if we don't
have two pages being mapped, we could easily read from a non-mapped
virtual address, which will trigger the UB sanitizer.
Also, we need to treat the FADT structure as volatile and const, as it
may change at any time, but we should not touch (write) it anyhow.
In VFS::rename, if new_path is equal to '/', then, parent custody is
set to null.
VFS::rename would then use parent custody without checking it first.
Fixed VFS::rename to check both old and new path parent custody
before actually using them.
write_bytes is called with a count of 0 bytes if a directory is being
deleted, because in that case even the . and .. pseudo directories are
getting removed. In this case write_bytes is now a no-op.
Before write_bytes would fail because it would check to see if there
were any blocks available to write in (even though it wasn't going to
write in them anyway).
This behaviour was uncovered because of a recent change where
directories are correctly reduced in size. Which in this case results in
all the blocks being removed from the inode, whereas previously there
would be some stale blocks around to pass the check.
e2fsck considers all blocks reachable through any of the pointers in
m_raw_inode.i_block as part of this inode regardless of the value in
m_raw_inode.i_size. When it finds more blocks than the amount that
is indicated by i_size or i_blocks it offers to repair the filesystem
by changing those values. That will actually cause further corruption.
So we must zero all pointers to blocks that are now unused.
The current method of emitting performance events requires a bit of
boiler plate at every invocation, as well as having to ignore the
return code which isn't used outside of the perf event syscall. This
change attempts to clean that up by exposing high level API's that
can be used around the code base.
Ext2 directory contents are stored in a linked list of ext2_dir_entry
structs. There is no sentinel value to determine where the list ends.
Instead the list fills the entirety of the allocated space for the
inode.
Previously the inode was not correctly resized when it became smaller.
This resulted in stale data being interpreted as part of the linked list
of directory entries.
When reading UDP packets from userspace with recvmsg()/recv() we
would hit a VERIFY() if the supplied buffer is smaller than the
received UDP packet. Instead we should just return truncated data
to the caller.
This can be reproduced with:
$ dd if=/dev/zero bs=1k count=1 | nc -u 192.168.3.190 68
We use a global setting to determine if Caps Lock should be remapped to
Control because we don't care how keyboard events come in, just that they
should be massaged into different scan codes.
The `proc` filesystem is able to manipulate this global variable using
the `sysctl` utility like so:
```
# sysctl caps_lock_to_ctrl=1
```
An IP socket can now join a multicast group by using the
IP_ADD_MEMBERSHIP sockopt, which will cause it to start receiving
packets sent to the multicast address, even though this address does
not belong to this host.
When using `sysctl` you can enable/disable values by writing to the
ProcFS. Some drift must have occured where writing was failing due to
a missing `set_mtime` call. Whenever one `write`'s a file the modified
time (mtime) will be updated so we need to implement this interface in
ProcFS.
The fact that current_time can "fail" makes its use a bit awkward.
All callers in the Kernel are trusted besides syscalls, so assert
that they never get there, and make sure all current callers perform
validation of the clock_id with TimeManagement::is_valid_clock_id().
I have fuzzed this change locally for a bit to make sure I didn't
miss any obvious regression.
The variety of checks for Processor::id() == 0 could use some assistance
in the readability department. This change adds a new function to
represent this check, and replaces the comparison everywhere it's used.
FileDescriptionBlocker::m_should_block was shadowing the parent's
FileBlocker::m_should_block variable, which would cause should_block()
to return the wrong value.
Found by @gunnarbeutner
This solves a problem where checking whether a thread is an idle
thread may require iterating all processors if it is not the idle
thread of the current processor.
Previously we would return a 0xdeadc0de frame for every kernel frame
in the real kernel stack when an non super-user issued the request.
This isn't useful, and just produces visual clutter in tools which
attempt to symbolize stacks.
While hacking on `sysctl` an issue in ProcFS was making me unable to
read/write from `/proc/sys/XXX`. Some directories in the ProcFS are not
actually backed by a process and need to return `nullptr` so callbacks
get properly set. We now do an explicit check for the parent to ensure
it's one that is PID-based.
The error handling in all these cases was still using the old style
negative values to indicate errors. We have a nicer solution for this
now with KResultOr<T>. This change switches the interface and then all
implementers to use the new style.
Our current implementation does not work in the special case in which
both shift keys are pressed, and then only one of the keys is released,
as this would result in writing lower case letters, instead of the
expected upper case letters.
This commit fixes that by keeping track of the amount of shift keys
that are pressed (instead of if any are at all), and only switching to
the unshifted keymap once all of them are released.
The previous patch already helped with this, however my idea of only
reading a few packets didn't work and we'd still sometimes end up not
receiving any more packets from the E1000 interface.
With this patch applied my NIC seems to receive packets just fine, at
least for now.
The dance here is not complicated, but it is something that should
be taken note of. Since we append to both lists, we don't want to
orphan the new Inode in the m_links/m_subfolders Vector in the event
that the append to m_parent_fs.m_nodes fails.
Raw sockets don't need a local port, so we shouldn't fail operations
if allocation yields an ENOPROTOOPT.
I'm not in love with the factoring here, just patching up the bug.
Without this patch we end up with sockets in the listener's accept
queue with state 'closed' when doing stealth SYN scans:
Client -> Server: SYN for port 22
Server -> Client: SYN/ACK
Client -> Server: RST (i.e. don't complete the TCP handshake)
Previously, TLS data was always zero-initialized.
To support initializing the values of TLS data, sys$allocate_tls now
receives a buffer with the desired initial data, and copies it to the
master TLS region of the process.
The DynamicLinker gathers the initial TLS image and passes it to
sys$allocate_tls.
We also now require the size passed to sys$allocate_tls to be
page-aligned, to make things easier. Note that this doesn't waste memory
as the TLS data has to be allocated in separate pages anyway.
For example Linux accepts an additional argument for flags in accept4()
that let the user specify what flags they want. However, by default
accept() should not inherit those flags from the listener socket.
When there is more than one file descriptor for a file closing
one of them should not close the underlying file.
Previously this relied on the file's ref_count() but at least
for sockets this didn't work reliably.
Theoretically the append should never fail as we have in-line storage
of FD_SETSIZE, which should always be enough. However I'm planning on
removing the non-try variants of AK::Vector when compiling in kernel
mode in the future, so this will need to go eventually. I suppose it
also protects against some unforeseen bug where we we can append more
than FD_SETSIZE items.
Theoretically the append should never fail as we have in-line storage
of 2, which should be enough. However I'm planning on removing the
non-try variants of AK::Vector when compiling in kernel mode in the
future, so this will need to go eventually. I suppose it also protects
against some unforeseen bug where we we can append more than 2 items.
sys$purge() is a bit unique, in that it is probably in the systems
advantage to attempt to limp along if we hit OOM while processing
the vmobjects to purge. This change modifies the algorithm to observe
OOM and continue trying to purge any previously visited VMObjects.
GCC with -flto is more aggressive when it comes to inlining and
discarding functions which is why we must mark some of the functions
as NEVER_INLINE (because they contain asm labels which would be
duplicated in the object files if the compiler decides to inline
the function elsewhere) and __attribute__((used)) for others so
that GCC doesn't discard them.
This commit will add MSG_PEEK support, which allows a package to be
seen without taking it from the buffer, so that a subsequent recv()
without the MSG_PEEK flag can pick it up.
We had some inconsistencies before:
- Sometimes "The", sometimes "the"
- Sometimes trailing ".", sometimes no trailing "."
I picked the most common one (lowecase "the", trailing ".") and applied
it to all copyright headers.
By using the exact same string everywhere we can ensure nothing gets
missed during a global search (and replace), and that these
inconsistencies are not spread any further (as copyright headers are
commonly copied to new files).
The current implementation would only check the first name.length()
characters match, which means any kernel symbol that the provided name
is a prefix of would match, instead of the actual matching symbol.
This commit fixes that by using StringView::operator==() for the
comparison, which already checks the equality correctly.
Lots of people are confused by the error message you get when the
Toolchain is behind/messed up:
'initializer-list: No such file or directory'
Before this error can happen, catch the problem at CMake configure time,
and provide them with an actionable error message.
Make this stuff a bit easier to maintain by using the
root level variables to build up the Toolchain paths.
Also leave a note for future editors of BuildIt.sh to
give them warning about the other changes they'll need
to make.
Previously the E1000 network adapter would stop receiving further
packets when an RX buffer overrun occurred. This was the case
when connecting the adapter to a real network where enough broadcast
traffic caused the buffer to be full before the kernel had a chance
to clear the RX buffer.
The overall design is the same, but we change a few things,
like decreasing the amount of blocking forever loops. The goal
is to ensure the kernel won't hang forever when dealing with
buggy hardware.
Also, we reset the channel when initializing it, just in case the
hardware was in bad state before we start use it.
