This syscall is only concerned with the current thread (except in the
case of a pledge violation, when it will add some details about that
to the process coredump metadata. That stuff is already serialized.)
This syscall operates on the file descriptor table, and on individual
open file descriptions. Both of those are already protected by scoped
locking mechanisms.
This syscall had a TOCTOU where it checked the peer's PPID before
locking the protected data (where the PPID is stored).
After closing the race window, we can mark the syscall as not needing
the big lock.
There was a whole bunch of ref counting churn coming from Mutex, which
had a RefPtr<Thread> m_holder to (mostly) point at the thread holding
the mutex.
Since we never actually dereference the m_holder value, but only use it
for identity checks against thread pointers, we can store it as an
uintptr_t and skip the ref counting entirely.
Threads can't die while holding a mutex anyway, so there's no risk of
them going missing on us.
These were stored in a bunch of places. The main one that's a bit iffy
is the Mutex::m_holder one, which I'm going to simplify in a subsequent
commit.
In Plan9FS and WorkQueue, we can't make the NNRPs const due to
initialization order problems. That's probably doable with further
cleanup, but left as an exercise for our future selves.
Before starting this, I expected the thread blockers to be a problem,
but as it turns out they were super straightforward (for once!) as they
don't mutate the thread after initiating a block, so they can just use
simple const-ified NNRPs.
- Instead of taking the first new thread as an out-parameter, we now
bundle the process and its first thread in a struct and use that
as the return value.
- Make all Process factory functions return ErrorOr. Use this to convert
some places to more TRY().
- Drop the "try_" prefix on Process factory functions.
The only persistent one of these was Thread::m_process and that never
changes after initialization. Make it const to enforce this and switch
everything over to RefPtr & NonnullRefPtr.
- The host custody never changes after initialization, so there's no
need to protect it with a spinlock.
- To enforce the fact that some members don't change after
initialization, make them const.
There was only one permanent storage location for these: as a member
in the Mount class.
That member is never modified after Mount initialization, so we don't
need to worry about races there.
This matches x86_64's behaviour in common_trap_exit. (called from
thread_context_first_enter)
Currently thread_context_first_enter is only called when creating new
processes from scratch, in which case this doesn't change the actual
behaviour. But once thread_context_first_enter is called as part of
execve support, this will ensure the Thread's m_current_trap is set
correctly to the new trap frame.
The details of the specific interrupt bits that must be turned on are
irrelevant to the sys$execve implementation. Abstract it away to the
Processor implementations using the InterruptsState enum.
Forked processes already have an existing value for the link register,
which we can't overwrite. But since they're forked the original link
register value that points to exit_kernel_thread was already saved
somewhere on the stack, so it's ok not to set it.
This commit fixes a kernel panic that happened when unmounting
a disk due to an invalid memory access.
This was because `DiskCache` initializes two linked lists that use
an argument `KBuffer` as the storage for their elements.
Since the member `KBuffer` was declared after the two lists,
when `DiskCache`'s destructor was called, then `KBuffer`'s destructor
was called before the ones of the two lists, causing a page fault in
the kernel.
Instead, only update it when the Caps Lock key event is generated and
remapping to the Ctrl key is enabled.
This fixes a bug that when enabling remapping Caps Lock key to the Ctrl
key, the original Ctrl key is no longer usable.
This is an implementation that tries to follow the spec as closely as
possible, and works with Qemu's Intel HDA and some bare metal HDA
controllers out there. Compiling with `INTEL_HDA_DEBUG=on` will provide
a lot of detailed information that could help us getting this to work
on more bare metal controllers as well :^)
Output format is limited to `i16` samples for now.
This reverts commit 187723776a.
This was reverted because it was needed until the aarch64 port
got an SD card driver
Co-authored-by: Ollrogge <nils-ollrogge@outlook.de>
It appeared that we sometimes failed to invoke synchronous commands on
the GPU. To temporarily fix this, wait 10 milliseconds for commands to
complete before failing.
According to the specification, modesetting can be invoked with no need
for flushing the framebuffer nor with DMA to transfer the framebuffer
rendering.
This configuration exposes a suboptimal mechanism to access other
VirtIO device configurations. It is also the only configuration to use a
zero length for a configuration structure, and specify a valid BAR which
triggered a kernel panic when attaching a virtio-gpu-pci device before
95b15e4901 was applied.
The real solution for that problem is to ignore this configuration type
because we never actually use it. It means that we can VERIFY that all
other configuration types have a valid length, as being expected.
Before, the mapping of our HBA region would be done in the constructor.
Since this can fail, I moved it into initialize().
Additionally, we now use the TypedMapping helper for mapping the HBA
instead of doing it manually. This actually uncovered a bug where we
would ignore any possible offset into the page we were mapping, which
caused us to miss the mapped registers entirely.
It makes much more sense to have these actions being performed via the
prctl syscall, as they both require 2 plain arguments to be passed to
the syscall layer, and in contrast to most syscalls, we don't get in
these removed syscalls an automatic representation of Userspace<T>, but
two FlatPtr(s) to perform casting on them in the prctl syscall which is
suited to what has been done in the removed syscalls.
Also, it makes sense to have these actions in the prctl syscall, because
they are strongly related to the process control concept of the prctl
syscall.
Use the same pattern for Ramdisk similar to other storage devices during
device initialization. This will propagate errors if the Ramdisk fails
to initialize.
Storage controllers are initialized during init and are never modified.
NonnullRefPtr can be safely used instead of the NonnullLockRefPtr. This
also fixes one of the UB issue that was there when using an NVMe device
because of NonnullLockRefPtr.
We can add proper locking when we need to modify the storage controllers
after init.
Any userspace cpp file that included <syscall.h> would end up with
a large glob of Kernel headers included, all the way down to
Kernel/Arch/x86_64/CPU.h and friends.
Only the kernel needs RegisterState, so hide it from userspace.
This is done with 2 major steps:
1. Remove JailManagement singleton and use a structure that resembles
what we have with the Process object. This is required later for the
second step in this commit, but on its own, is a major change that
removes this clunky singleton that had no real usage by itself.
2. Use IntrusiveLists to keep references to Process objects in the same
Jail so it will be much more straightforward to iterate on this kind
of objects when needed. Previously we locked the entire Process list
and we did a simple pointer comparison to check if the checked
Process we iterate on is in the same Jail or not, which required
taking multiple Spinlocks in a very clumsy and heavyweight way.
The LUN.target_id parameter points to a NVMe Namespace which starts from
1 and not 0. Fix the document to reflect the same while addressing a
nvme device in the boot parameters
This was mostly straightforward, as all the storage locations are
guarded by some related mutex.
The use of old-school associated mutexes instead of MutexProtected
is unfortunate, but the process to modernize such code is ongoing.
There's no plan to support ATAPI in the foreseeable future. ATAPI is
considered mostly as an extension to pass SCSI commands over ATA-link
compatible channel (which could be a physical SATA or PATA).
ATAPI is mostly used for controlling optical drives which are considered
obsolete in 2023, and require an entire SCSI abstraction layer we don't
exhibit with bypassing ioctls for sending specific SCSI commands in many
control-flow sequences for actions being taken for such hardware.
Therefore, let's make it clear we don't support ATAPI (SCSI over ATA)
unless someone picks it up and proves otherwise that this can be done
cleanly and also in a relevant way to our project.
These configurations are simply invalid. Ignoring those allow us to boot
with the virtio-gpu-pci device (in addition to the already supported
virtio-vga PCI device).
This patch switches away from {Nonnull,}LockRefPtr to the non-locking
smart pointers throughout the kernel.
I've looked at the handful of places where these were being persisted
and I don't see any race situations.
Note that the process file descriptor table (Process::m_fds) was already
guarded via MutexProtected.
This class had slightly confusing semantics and the added weirdness
doesn't seem worth it just so we can say "." instead of "->" when
iterating over a vector of NNRPs.
This patch replaces NonnullRefPtrVector<T> with Vector<NNRP<T>>.
Before of this patch, we looked at the unveil data of the FinalizerTask,
which naturally doesn't have any unveil restrictions, therefore allowing
an unveil bypass for a process that enabled performance coredumps.
To ensure we always check the dumped process unveil data, an option to
pass a Process& has been added to a couple of methods in the class of
VirtualFileSystem.
This allows us to get rid of an include to LibC/sys/ttydefaults.h in the
Kernel TTY implementation.
Also, move ttydefchars static const struct to another file called
Kernel/API/ttydefaultschars.h, so it could be used too in the Kernel TTY
implementation without the need to include anything from LibC.
We don't actually need the va_list and other stdarg definitions in the
kernel, because we actually don't use the "pure" printf interface in any
kernel code at all, but we retain the snprintf declaration because the
libstdc++ library still need it to be declared and extern'ed.
Instead of using a special case of the annotate_mapping syscall, let's
introduce a new prctl option to disallow further annotations of Regions
as new syscall Region(s).
Since the ProcFS doesn't hold many global objects within it, the need
for a fully-structured design of backing components and a registry like
with the SysFS is no longer true.
To acommodate this, let's remove all backing store and components of the
ProcFS, so now it resembles what we had in the early days of ProcFS in
the project - a mostly-static filesystem, with very small amount of
kmalloc allocations needed.
We still use the inode index mechanism to understand the role of each
inode, but this is done in a much "static"ier way than before.
Before doing a check if offset_in_region + num_bytes of the transfer
descriptor are together more than NUM_TRANSFER_REGION_PAGES * PAGE_SIZE,
check that addition of both of these parameters will not simply overflow
which could lead to out-of-bounds read/write.
Fixes#17518.
Support all the available clocks in clock_getres(). Also, fix this
function to use the actual ticks per second value, not the constant
`_SC_CLK_TCK` (which is always equal to 8) and move the resolution
computation logic to TimeManagement.
Dealing with the specific details of how to program a PLL should be done
in a separate file to ensure we can easily expand it to support future
generations of the Intel graphics device.
ENODEV better represents the fact that there might be no display device
(e.g. a monitor) connected to the connector, therefore we should return
this error.
Another reason to not use ENOTIMPL is that it's a requirement for all
DisplayConnectors to put a valid EDID in place even for a hardware we
don't currently support mode-setting in runtime.
Instead of doing that on the IntelDisplayPlane class, let's have this in
derived classes so these classes can decide how to use the settings that
were provided before calling the enable method.
It became apparent to me that future generations of the Intel graphics
chipset utilize the same register set as part of the Transcoder register
set. Therefore, it should be included now in the Transcoder class.
In the real world, graphics hardware tend to have multiple display
connectors. However, usually the connectors share one register space but
still keeping different PLL timings and display lanes.
This new class should represent a group of multiple display connectors
working together in the same Intel graphics adapter. This opens an
opportunity to abstract the interface so we could support future Intel
iGPU generations.
This is also a preparation before the driver can support newer devices
and utilize their capabilities.
The mentioned preparation is applied in a these aspects:
1. The code is splitted into more classes to adjust to future expansion.
2 classes are introduced: IntelDisplayPlane and IntelDisplayTranscoder,
so the IntelDisplayPlane controls the plane registers and second class
controls the pipeline (transcoder, encoder) registers. On gen4 it's not
really useful because there are probably one plane and one encoder to
care about, but in future generations, there are likely to be multiple
transcoders and planes to accommodate multi head support.
2. The set_edid_bytes method in the DisplayConnector class can now be
told to not assume the provided EDID bytes are always invalid. Therefore
it can refrain from printing error messages if this flag parameter is
true. This is useful for supporting real hardware situation when on boot
not all ports are connected to a monitor, which can result in floating
bus condition (essentially all the bytes we read are 0xFF).
3. An IntelNativeDisplayConnector could now be set to flag other types
of connections such as eDP (embedded DisplayPort), Analog output, etc.
This is important because on the Intel gen4 graphics we could assume to
have one analog output connector, but on future generations this is very
likely to not be the case, as there might be no VGA outputs, but rather
only an eDP connector which is converted to VGA by a design choice of
the motherboard manufacturer.
4. Add ConnectorIndex to IntelNativeDisplayConnector class - Currently
this is used to verify we always handle the correct connector when doing
modesetting.
Later, it will be used to locate special settings needed when handling
connector requests.
5. Prepare to support more types of display planes. For example, the
Intel Skylake register set for display planes is a bit different, so
let's ensure we can properly support it in the near future.
This subdirectory is meant to hold all constant data related to the
kernel. This means that this data is never meant to updated and is
relevant from system boot to system shutdown.
Move the inodes of "load_base", "cmdline" and "system_mode" to that
directory. All nodes under this new subdirectory are generated during
boot, and therefore don't require calling kmalloc each time we need to
read them. Locking is also not necessary, because these nodes and their
data are completely static once being generated.
This is considered somewhat an abstraction layer violation, because we
should always let userspace to decide on the root filesystem mount flags
because it allows the user to configure the mount table to preferences
that they desire.
Now that SystemServer is modified to re-mount the root mount with the
desired flags, we can just mount the root filesystem without assuming
special flags.
The check of ensuring we are not trying to read beyond the end of the
inode data buffer is already there, it's just that we need to disallow
further reading if the read offset equals to the inode data size.
Apparently we lacked this important check from the beginning of this
piece of code. This check is crucial to ensure we only give back data
being related to the FATInode data buffer and nothing beyond it.
This is necessary to support the wayland protocol.
I also moved the CMSG_* macros to the kernel API since they are used in
both kernel and userspace.
this does not break ntpquery/SCM_TIMESTAMP.
There was a bug in which bound Inodes would lose all their references
(because localsocket does not reference them), and they would be
deallocated, and clients would get ECONNREFUSED as a result. now
LocalSocket has a strong reference to inode so that the inode will live
as long as the socket, and Inode has a weak reference to the socket,
because if the socket stops being referenced anywhere it should not be
bound.
This still prevents the reference loop that
220b7dd779 was trying to fix.
Even though we currently build all of Userland and the Kernel with the
-mstrict-align flag, the compiler will still emit unaligned memory
accesses. To work around this, we disable the check for now. See
https://github.com/SerenityOS/serenity/issues/17516 for the relevant
issue.
This commit adds Processor::set_thread_specific_data, and this function
is used to factor out architecture specific implementation of setting
the thread specific data. This function is implemented for
aarch64 and x86_64, and the callsites are changed to use this function
instead.
This new method is meant to be used in both userspace and kernel code.
The idea is to allow printing of a verbose message and then returning an
errno code which is the proper mechanism for kernel code because we
should almost always assume that such error will be propagated back to
userspace in some way, so the userspace code could reasonably decode it.
For userspace code however, this new method is meant to be a simple
wrapper for Error::from_string_view, because for most invocations, it's
much more useful to have a verbose & literal error than a errno code, so
we simply ignore that errno code completely in such context.
Returning literal strings is not the proper action here, because we
should always assume that error could be propagated back to userland, so
we need to keep a valid errno when returning an Error.
Returning literal strings is not the proper action here, because we
should always assume that error could be propagated back to userland, so
we need to keep a valid errno when returning an Error.
For example, consider cases where we want to propagate errors only in
specific instances:
auto result = read_data(); // something like ErrorOr<ByteBuffer>
if (result.is_error() && result.error().code() != EINTR)
continue;
auto bytes = TRY(result);
The TRY invocation will currently copy the byte buffer when the
expression (in this case, just a local variable) is stored into
_temporary_result.
This patch binds the expression to a reference to prevent such copies.
In less trival invocations (such as TRY(some_function()), this will
incur only temporary lifetime extensions, i.e. no functional change.
This is needed so we can retrieve the registers of a traced
thread that was attached to while it was running.
Attaching with ptrace to a running thread sends SIGSTOP to it.
This adds the necessary code to init.cpp to be able to execute the first
userspace process. To do this, first the filesystem code is initialized,
which will use the ramdisk embedded into the kernel image. Then the
first userspace process, /bin/SystemServer is executed. :^)
The ramdisk code is used as it is useful for the bring-up of the aarch64
port, however once the kernel has support for better ram-based
filesystems, the ramdisk code will be removed again.
The emulated aarch64 CPU does not contain the RNG cpu feature, so the
random number generator was not seeded. This commit adds a fallback to
use TimeManagement as a entropy source, such that get_good_random_bytes
works, which is needed for running the first userspace application on
aarch64.
This sets up the correct ThreadRegisters state when a process is
exec'ed, which happens when the first userspace application is executed.
Also changes Processor.cpp to get the stack pointer from the
ThreadRegisters.
This allows the function to be called from other translation units, in
particular this allows the CrashHandler.cpp file to be shared between
aarch64 and x86_64.
Setting the kernel_load_base variable caused backtracking to regress, so
to have proper backtracing the calculation of the symbol address in
KSyms.cpp needs to keep into account that the aarch64 kernel is linked
at a high virtual memory address.
When we execute in userspace, the exception level is EL0, so to handle
exceptions, such as interrupts, and syscalls, we need to add handlers to
vector_table.S. For now we only support running userspace applications
in AArch64 mode, so this commit only adds the handlers for that mode.
To detect instruction aborts, a helper to Registers.h is added, and used
in Interrupts.cpp. Additionally, the PageFault class gets a setter to
set the PageFaults m_is_instruction_fetch bool, and is also used in
Interrupts.cpp.
This reverts commit 4e0f85432a as the
ramdisk code is useful for the bring-up of the aarch64 port. Once the
kernel supports better ram-based filesystems, this code will be removed
again.
This replaces manually grabbing the thread's main lock.
This lets us remove the `get_thread_name` and `set_thread_name` syscalls
from the big lock. :^)
This filesystem is based on the code of the long-lived TmpFS. It differs
from that filesystem in one keypoint - its root inode doesn't have a
sticky bit on it.
Therefore, we mount it on /dev, to ensure only root can modify files on
that directory. In addition to that, /tmp is mounted directly in the
SystemServer main (start) code, so it's no longer specified in the fstab
file. We ensure that /tmp has a sticky bit and has the value 0777 for
root directory permissions, which is certainly a special case when using
RAM-backed (and in general other) filesystems.
Because of these 2 changes, it's no longer needed to maintain the TmpFS
filesystem, hence it's removed (renamed to RAMFS), because the RAMFS
represents the purpose of this filesystem in a much better way - it
relies on being backed by RAM "storage", and therefore it's easy to
conclude it's temporary and volatile, so its content is gone on either
system shutdown or unmounting of the filesystem.
When doing PT_SETREGS, we want to verify that the debugged thread is
executing in usermode.
b2f7ccf refactored things and flipped the relevant check around, which
broke things that use PT_SETREGS (for example, stepping over
breakpoints with sdb).
Splitting the I2C-related code lets the DisplayConnector code to utilize
I2C operations without caring about the specific details of the hardware
and allow future expansion of the driver to other newer generations
sharing the same GMBus code.
We should require a timeout for GMBus operations always, because faulty
hardware could let us just spin forever. Also, if nothing is listening
to the bus (which should result in a NAK), we could also spin forever.
Thanks to Andrew Kaster, which gave a review back in October, about a
big PR I opened (#15502), I managed to figure out why we always had a
problem with the first byte being read into the EDID buffer with the
GMBus code. It turns out that this simple invalid cast was making the
entire problem and using the correct AK::Array::data() method fixed this
notorious long standing problem for good.
This patch removes the x86 mechanism for calling syscalls, favoring
the more modern syscall instruction. It also moves architecture
dependent code from functions that are meant to be architecture
agnostic therefore paving the way for adding more architectures.
The function signal_trampoline_dummy was using int 0x82 to call
SC_sigreturn. Since x86 is no longer supported, the correct way
to call a syscall is using the syscall instruction.
This paves the way to remove the syscall trap handling mechanism.
This is done by merging all scattered pieces of derived classes from the
ProcFSInode class into that one class, so we don't use inheritance but
rather simplistic checks to determine the proper code for each ProcFS
inode with its specific characteristics.
This will cause page faults to be generated. Since the previous commits
introduced the handling of page faults, we can now actually correctly
handle page faults.
The code in PageDirectory.cpp now keeps track of the registered page
directories, and actually sets the TTBR0_EL1 to the page table base of
the currently executing thread. When context switching, we now also
change the TTBR0_EL1 to the page table base of the thread that we
context switch into.
The handling of page tables is very architecture specific, so belongs
in the Arch directory. Some parts were already architecture-specific,
however this commit moves the rest of the PageDirectory class into the
Arch directory.
While we're here the aarch64/PageDirectory.{h,cpp} files are updated to
be aarch64 specific, by renaming some members and removing x86_64
specific code.
The class used to look at the x86_64 specific exception code to figure
out what kind of page fault happend, however this refactor allows
aarch64 to use the same class.
Various places in the kernel were manually checking the cs register for
x86_64, however to share this with aarch64 a function in RegisterState
is added, and the call-sites are updated. While we're here the
PreviousMode enum is renamed to ExecutionMode.
Until now the kernel was always executing with SP_EL0, as this made the
initial dropping to EL1 a bit easier. This commit changes this behaviour
to use the corresponding SP_ELx for each exception level.
To make sure that the execution of the C++ code can continue, the
current stack pointer is copied into the corresponding SP_ELx just
before dropping an exception level.
For each exposed PCI device in sysfs, there's a new node called "rom"
and by reading it, it exposes the raw data of a PCI option ROM blob to
a user for examining the blob.
There are now 2 separate classes for almost the same object type:
- EnumerableDeviceIdentifier, which is used in the enumeration code for
all PCI host controller classes. This is allowed to be moved and
copied, as it doesn't support ref-counting.
- DeviceIdentifier, which inherits from EnumerableDeviceIdentifier. This
class uses ref-counting, and is not allowed to be copied. It has a
spinlock member in its structure to allow safely executing complicated
IO sequences on a PCI device and its space configuration.
There's a static method that allows a quick conversion from
EnumerableDeviceIdentifier to DeviceIdentifier while creating a
NonnullRefPtr out of it.
The reason for doing this is for the sake of integrity and reliablity of
the system in 2 places:
- Ensure that "complicated" tasks that rely on manipulating PCI device
registers are done in a safe manner. For example, determining a PCI
BAR space size requires multiple read and writes to the same register,
and if another CPU tries to do something else with our selected
register, then the result will be a catastrophe.
- Allow the PCI API to have a united form around a shared object which
actually holds much more data than the PCI::Address structure. This is
fundamental if we want to do certain types of optimizations, and be
able to support more features of the PCI bus in the foreseeable
future.
This patch already has several implications:
- All PCI::Device(s) hold a reference to a DeviceIdentifier structure
being given originally from the PCI::Access singleton. This means that
all instances of DeviceIdentifier structures are located in one place,
and all references are pointing to that location. This ensures that
locking the operation spinlock will take effect in all the appropriate
places.
- We no longer support adding PCI host controllers and then immediately
allow for enumerating it with a lambda function. It was found that
this method is extremely broken and too much complicated to work
reliably with the new paradigm being introduced in this patch. This
means that for Volume Management Devices (Intel VMD devices), we
simply first enumerate the PCI bus for such devices in the storage
code, and if we find a device, we attach it in the PCI::Access method
which will scan for devices behind that bridge and will add new
DeviceIdentifier(s) objects to its internal Vector. Afterwards, we
just continue as usual with scanning for actual storage controllers,
so we will find a corresponding NVMe controllers if there were any
behind that VMD bridge.
There’s similar RDRAND register (encoded as ‘s3_3_c2_c4_0ʼ) to be
added if needed. RNG CPU feature on Aarch64 guarantees existence of both
RDSEED and RDRAND registers simultaneously—in contrast to x86-64, where
respective instructions are independent of each other.
This is the same address that the x86_64 kernel runs at, and allows us
to run the kernel at a high virtual memory address. Since we now run
completely in high virtual memory, we can also unmap the identity
mapping. Additionally some changes in MMU.cpp are required to
successfully boot.
Since we link the kernel at a high virtual memory address, the addresses
of global variables are also at virtual addresses. To be able to access
them without the MMU enabled, we have to subtract the
KERNEL_MAPPING_BASE.
Compile source files that run early in the boot process without the MMU
enabled, without stack protector and sanitizers. Enabling them will
cause the compiler to insert accesses to global variables, such as
__stack_chk_guard, which cause the CPU to crash, because these variables
are linked at high virtual addresses, which the CPU cannot access
without the MMU enabled.
This is a separate file that behaves similar to the Prekernel for
x86_64, and makes sure the CPU is dropped to EL1, the MMU is enabled,
and makes sure the CPU is running in high virtual memory. This code then
jumps to the usual init function of the kernel.
This was previously hardcoded this to be the physical memory range,
since we identity mapped the memory, however we now run the kernel at
a high virtual memory address.
Also changes PageDirectory.h to store up-to 512 pages, as the code now
needs access to more than 4 pages.
As the kernel is now linked at high address in virtual memory, we cannot
use absolute addresses as they refer to high addresses in virtual
memory. At this point in the boot process we are still running with the
MMU off, so we have to make sure the accesses are using physical memory
addresses.
This function will be used once the kernel runs in high virtual memory
to unmap the identity mapping as userspace will later on use this memory
range instead.
And use it the code that will be part of the early boot process.
The PANIC macro and dbgln functions cannot be used as it accesses global
variables, which in the early boot process do not work, since the MMU is
not yet enabled.
In the upcoming commits, we'll change the kernel to run at a virtual
address in high memory. This commit prepares for that by making sure the
kernel and mmio are mapped into high virtual memory.
A lot of places were relying on AK/Traits.h to give it strnlen, memcmp,
memcpy and other related declarations.
In the quest to remove inclusion of LibC headers from Kernel files, deal
with all the fallout of this included-everywhere header including less
things.
This header has always been fundamentally a Kernel API file. Move it
where it belongs. Include it directly in Kernel files, and make
Userland applications include it via sys/ioctl.h rather than directly.
Reduce inclusion of limits.h as much as possible at the same time.
This does mean that kmalloc.h is now including Kernel/API/POSIX/limits.h
instead of LibC/limits.h, but the scope could be limited a lot more.
Basically every file in the kernel includes kmalloc.h, and needs the
limits.h include for PAGE_SIZE.
A lot of interrupt numbers are initialized with the unhandled interrupt
handler. Whenever a new handler is registered on one of these
interrupts, the old handler is unregistered first. Let's not be verbose
about this since it is perfectly normal.
Following registers accessors are updated and put in use:
* ID_AA64ISAR0_EL1, Instruction Set Attribute Register 0
Accessors for following registers are added and put in use:
* ID_AA64ISAR1_EL1, Instruction Set Attribute Register 1
* ID_AA64ISAR2_EL1, Instruction Set Attribute Register 2
* ID_AA64MMFR1_EL1, AArch64 Memory Model Feature Register 1
* ID_AA64MMFR2_EL1, AArch64 Memory Model Feature Register 2
* ID_AA64MMFR3_EL1, AArch64 Memory Model Feature Register 3
* ID_AA64MMFR4_EL1, AArch64 Memory Model Feature Register 4
* ID_AA64PFR0_EL1, AArch64 Processor Feature Register 0
* ID_AA64PFR1_EL1, AArch64 Processor Feature Register 1
* ID_AA64PFR2_EL1, AArch64 Processor Feature Register 2
* ID_AA64ZFR0_EL1, AArch64 SVE Feature ID register 0
* ID_AA64SMFR0_EL1, AArch64 SME Feature ID register 0
* ID_AA64DFR0_EL1, AArch64 Debug Feature Register 0
* ID_AA64DFR1_EL1, AArch64 Debug Feature Register 1
Additionally, there are few CPU features detected with
* TCR_EL1, Translation Control Register
but detection mechanism using it (for LPA/LPA2) is probably wrong as
this is control register, not a id register, and needs further work.
Finally, following registers are provided. Former one is already used,
while latter is given for future use:
* MIDR_EL1, Main ID Register
* AIDR_EL1, Auxiliary ID Register
Settled for `cpu_feature_to_name` as that naming is more descriptive
and similarly named `cpu_feature_to_description` function will be
provided for Aarch64.
If USING_AK_GLOBALLY is not defined, the name IsLvalueReference might
not be available in the global namespace. Follow the pattern established
in LibTest to fully qualify AK types in macros to avoid this problem.