It doesn't make sense after introduction of routing table which allows
having multiple gateways for every interface, and isn't used by any of
the userspace programs now.
Let's use terminology from the the Intel manual to avoid confusion.
Also add `_string` suffixes to better distinguish the numeric values
from the string values.
Contrary to the past, we don't attempt to assume the real name of a TTY
device, but instead, we generate a pseudo name only when needed to do so
which is still OK because we don't break abstraction layer rules and we
still can provide userspace with the required information.
The obsolete ttyname and ptsname syscalls are removed.
LibC doesn't rely on these anymore, and it helps simplifying the Kernel
in many places, so it's an overall an improvement.
In addition to that, /proc/PID/tty node is removed too as it is not
needed anymore by userspace to get the attached TTY of a process, as
/dev/tty (which is already a character device) represents that as well.
Instead, hold the lock while we copy the contents to a stack-based
Vector then iterate on it without any locking.
Because we rely on heap allocations, we need to propagate errors back
in case of OOM condition, therefore, both PCI::enumerate API function
and PCI::Access::add_host_controller_and_enumerate_attached_devices use
now a ErrorOr<void> return value to propagate errors. OOM Error can only
occur when enumerating the m_device_identifiers vector under a spinlock
and trying to expand the temporary Vector which will be used locklessly
to actually iterate over the PCI::DeviceIdentifiers objects.
Reading from /proc/pci assumes we have PCI enabled and also enumerated.
However, if PCI is disabled for some reason, we can't allow the user to
read from it as there's no valuable data we can supply.
We can use `StringView::for_each_split_view` here to avoid the potential
allocation of `Vector<StringView>` elements we would get from the normal
Split view functions.
This was a premature optimization from the early days of SerenityOS.
The eternal heap was a simple bump pointer allocator over a static
byte array. My original idea was to avoid heap fragmentation and improve
data locality, but both ideas were rooted in cargo culting, not data.
We would reserve 4 MiB at boot and only ended up using ~256 KiB, wasting
the rest.
This patch replaces all kmalloc_eternal() usage by regular kmalloc().
We now use AK::Error and AK::ErrorOr<T> in both kernel and userspace!
This was a slightly tedious refactoring that took a long time, so it's
not unlikely that some bugs crept in.
Nevertheless, it does pass basic functionality testing, and it's just
real nice to finally see the same pattern in all contexts. :^)
Found due to smelly code in InodeFile::absolute_path.
In particular, this replaces the following misleading methods:
File::absolute_path
This method *never* returns an actual path, and if called on an
InodeFile (which is impossible), it would VERIFY_NOT_REACHED().
OpenFileDescription::try_serialize_absolute_path
OpenFileDescription::absolute_path
These methods do not guarantee to return an actual path (just like the
other method), and just like Custody::absolute_path they do not
guarantee accuracy. In particular, just renaming the method made a
TOCTOU bug obvious.
The new method signatures use KResultOr, just like
try_serialize_absolute_path() already did.
'bootmode' now only controls which set of services are started by
SystemServer, so it is more appropriate to rename it to system_mode, and
no longer validate it in the Kernel.
This exposes a small subset of the information exposed by the Linux
equivalent, and will be used to optimize applications that would like
to know the current CPU usage statistics, but don't want to read all of
the unrelated information in /proc/all
