This argument is always set to description.is_blocking(), but
description is also given as a separate argument, so there's no point
to piping it through separately.
The interrupts enabled check in the Kernel mutex is there so that we
don't lock mutexes within a spinlock, because mutexes reenable
interrupts and that will mess up the spinlock in more ways than one if
the thread moves processors. This check is guarded behind a debug flag
because it's too hard to fix all the problems at once, but we regressed
and weren't even getting to init stage 2 with it enabled. With this
commit, we get to stage 2 again. In early boot, there are no interrupts
enabled and spinlocks used, so we can sort of kind of safely ignore the
interrupt state. There might be a better solution with another boot
state flag that checks whether APs are up (because they have interrupts
enabled from the start) but that seems overkill.
Right now the TD and QH descriptor pools look to be susceptible
to a race condition in the event they are accessed simultaneously
by separate threads making USB transfers. This fix does not seem to
add any noticeable overhead.
IDEChannel which is an ATAPort derived class holded a NonnullRefPtr to a
parent IDEController, although we can easily defer the usage of it to
not be in the IDEChannel code at all, so it allows to keep NonnullRefPtr
to the parent ATAController in the ATAPort base class and only there.
This abstraction layer is mainly for ATA ports (AHCI ports, IDE ports).
The goal is to create a convenient and flexible framework so it's
possible to expand to support other types of controller (e.g. Intel PIIX
and ICH IDE controllers) and to abstract operations that are possible on
each component.
Currently only the ATA IDE code is affected by this, making it much
cleaner and readable - the ATA bus mastering code is moved to the
ATAPort code so more implementations in the near future can take
advantage of such functionality easily.
In addition to that, the hierarchy of the ATA IDE code resembles more of
the SATA AHCI code now, which means the IDEChannel class is solely
responsible for getting interrupts, passing them for further processing
in the ATAPort code to take care of the rest of the handling logic.
We do that to increase clarity of the major and secondary components in
the subsystem. To ensure it's even more understandable, we rename the
files to better represent the class within them and to remove redundancy
in the name.
Also, some includes are removed from the general components of the ATA
components' classes.
We are able to read the EDID from SysFS, therefore there's no need to
provide this ioctl on a DisplayConnector anymore.
Also, now we can simply require the video pledge to be set before doing
any ioctl on a DisplayConnector.
It is starting to get a little messy with how each device can try to add
or remove itself to either /sys/dev/block or /sys/dev/char directories.
To better do this, we introduce 4 virtual methods to take care of that,
so until we ensure all nodes in /sys/dev/block and /sys/dev/char are
actual symlinks, we allow the Device base class to call virtual methods
upon insertion or before being destroying, so it add itself elegantly to
either of these directories or remove itself when needed.
For special cases where we need to create symlinks, we have two virtual
methods to be called otherwise to do almost the same thing mentioned
before, but to use symlinks instead.
Under normal conditions (when mounting SysFS in /sys), there will be a
new directory in the /sys/devices directory called "graphics".
For now, under that directory there will be only a sub-directory called
"connectors" which will contain all DisplayConnectors' details, each in
its own sub-directory too, distinguished in naming with its minor
number.
Therefore, /sys/devices/graphics/connectors/MINOR_NUMBER/ will contain:
- General device attributes such as mutable_mode_setting_capable,
double_buffering_capable, flush_support, partial_flush_support and
refresh_rate_support. These values are exposed in the ioctl interface
of the DisplayConnector class too, but these can be useful later on
for command line utilities that want/need to expose these basic
settings.
- The EDID blob, simply named "edid". This will help userspace to fetch
the edid without the need of using the ioctl interface later on.
This change in fact does the following:
1. Use support for symlinks between /sys/dev/block/ storage device
identifier nodes and devices in /sys/devices/storage/{LUN}.
2. Add basic nodes in a /sys/devices/storage/{LUN} directory, to let
userspace to know about the device and its details.
These methods are essentially splitted from the after_inserting method
and the will_be_destroyed method so later on we can allow Storage
devices to override the after_inserting method and the will_be_destroyed
method while still being able to use shared functionality as before,
such as adding the device to and removing it from the device list.
This enforces us to remove duplicated code across the SysFS code. This
results in great simplification of how the SysFS works now, because we
enforce one way to treat SysFSDirectory objects.
This will be used later on to help connecting a node at /sys/dev/block/
that represents a Storage device to a directory in /sys/devices/storage/
with details on that device in that directory.
These methods will be used later on to introduce symbolic links support
in the SysFS, so the kernel will be able to resolve relative paths of
components in filesystem based on using the m_parent_directory pointer
in each SysFSComponent object.
LUN address is essentially how people used to address SCSI devices back
in the day we had these devices more in use. However, SCSI was taken as
an abstraction layer for many Unix and Unix-like systems, so it still
common to see LUN addresses in use. In Serenity, we don't really provide
such abstraction layer, and therefore until now, we didn't use LUNs too.
However (again), this changes, as we want to let users to address their
devices under SysFS easily. LUNs make sense in that regard, because they
can be easily adapted to different interfaces besides SCSI.
For example, for legacy ATA hard drive being connected to the first IDE
controller which was enumerated on the PCI bus, and then to the primary
channel as slave device, the LUN address would be 0:0:1.
To make this happen, we add unique ID number to each StorageController,
which increments by 1 for each new instance of StorageController. Then,
we adapt the ATA and NVMe devices to use these numbers and generate LUN
in the construction time.
This folder in the SysFS code represents everything related to /sys/dev,
which is a directory meant to be a convenient interface to track all IDs
of all block and character devices (ID = major:minor numbers).
This bug was probably around for a very long time, but it is noticeable
only under VirtualBox as it generated an non fatal error which caused a
kernel panic because we VERIFYed the wrong lock to be locked.
There's no point in keeping this method as we don't really care if a
graphics adapter is VGA compatible or not because we don't use this
method anymore.
There's no real value in separating physical pages to supervisor and
user types, so let's remove the concept and just let everyone to use
"user" physical pages which can be allocated from any PhysicalRegion
we want to use. Later on, we will remove the "user" prefix as this
prefix is not needed anymore.
We are limited on the amount of supervisor pages we can allocate, so
don't allocate from that pool. Supervisor pages are always below 16 MiB
barrier so using those was crucial when we used devices like the ISA
SoundBlaster 16 card, because that device required very low physical
addresses to be used.
This used to be needed to protect accesses to Process::all_instances.
That list now has a more granular lock, so we don't need to take the
scheduler lock.
This fixes a crash when we try to access a locked Thread::m_fds in the
loop, which calls Thread::block, which then asserts that the scheduler
lock must not be locked by the current process.
Fixes#13617
We should not allocate a kernel region inside the constructor of the
VGATextModeConsole class. We do use MUST() because allocation cannot
fail at this point, but that happens in the static factory method
instead.
The original intention was to support other types of consoles based on
standard VGA modes, but it never came to an implementation, nor we need
such feature at all.
Therefore, this class is not needed and can be removed.
While null StringViews are just as bad, these prevent the removal of
StringView(char const*) as that constructor accepts a nullptr.
No functional changes.
This prevents us from needing a sv suffix, and potentially reduces the
need to run generic code for a single character (as contains,
starts_with, ends_with etc. for a char will be just a length and
equality check).
No functional changes.
Each of these strings would previously rely on StringView's char const*
constructor overload, which would call __builtin_strlen on the string.
Since we now have operator ""sv, we can replace these with much simpler
versions. This opens the door to being able to remove
StringView(char const*).
No functional changes.
This commit moves the length calculations out to be directly on the
StringView users. This is an important step towards the goal of removing
StringView(char const*), as it moves the responsibility of calculating
the size of the string to the user of the StringView (which will prevent
naive uses causing OOB access).
We never supported VGA framebuffers and that folder was a big misleading
part of the graphics subsystem.
We do support bare-bones VGA text console (80x25), but that only happens
to be supported because we can't be 100% sure we can always initialize
framebuffer so in the worst scenario we default to plain old VGA console
so the user can still use its own machine.
Therefore, the only remaining parts of VGA is in the GraphicsManagement
code to help driving the VGA text console if needed.
Uncommitted pages (shared zero pages) can not contain any existing data
and can not be modified, so there's no point to committing a bunch of
extra pages to cover for them in the forked child.
