Until now, Genode's Linux system call bindings were based on original
Unix system calls that were later superseded by more flexibile variants.
E.g., 'openat' is a modern version of 'open'. Even though Linux upholds
the compatiblity with the original versions for existing architectures
like x86, the legacy syscalls are absent for the recently added AARCH64
architecture. A good overview of the system calls accross the prominent
architectures can be found at
https://chromium.googlesource.com/chromiumos/docs/+/master/constants/syscalls.md
This patch updates Genode's syscall bindings to avoid legacy versions,
thereby easing the support for AARCH64. The used "modern" versions
were introduced back in Linux version 2 days. So we are fine to rely
on them.
The patch slightly changes the signature for lx_stat because this system
call is merely used to check for the existance of a file and its size.
The new name 'lx_stat_size' draws a closer connection to its use case.
That said, the stat syscall has not been updated to the modern statx
since statx is still a fairly recent addition.
Issue #4136
This patch simplifies the use of the clone system call for creating
processes and threads. Until now, the binding used an opaque pointer
argument to pass context information to the newly created process or
thread. However, upon close inspection, this is not a strict
requirement.
A newly created thread accesses its contextual information by
using its stack pointer as key. The pointer argument is not used.
The creation of processes is strictly serialized because the
intermediate stack used in-between clone and execve is a global
variable. Since we rely on the serialization anyway, we can pass the
context information of a new process via a global variable as well.
This change simplifies the syscall binding for the upcoming AARCH64
support, which would otherwise require us to deal with the notion
of TLS on Linux.
Issue #4136
With the update to GCC 10, the compiler stopped with an error when compiling
places where a MAC address is copied from outside into a packed object using
the Net::Netaddress::copy method (e.g. in
Net::Arp_packet::dst_mac(Mac_address)):
! error: writing 6 bytes into a region of size 4 [-Werror=stringop-overflow=]
While trying to find a clean solution for this error, I found posts on
gcc.gnu.org and github that stated that the size calculations that cause these
errors are incorrect. Indeed, I could verify that the actual size of the two
regions was static and exactly the same in places were the error occured.
Furthermore, I couldn't find a way of making it more clear to the compiler
that the sizes are the same. By accident, we found that using the address of
the first element of the array that forms the second region instead of the
array address itself, somehow circumvents the error.
Fixes#4109
With the update to GCC 10 the compiler used to warn when using the internet
checksum functions on packet classes (like in
Net::Ipv4_packet::update_checksum):
warning: converting a packed ‘Net::[PACKET_CLASS]’ pointer
(alignment 1) to a ‘const uint16_t’ {aka ‘const short
unsigned int’} pointer (alignment 2) may result in an
unaligned pointer value
Apparently, the 'packed' attribute normally used on packet classes sets the
alignment of the packet class to 1. However, for the purpose of the
internet-checksum functions, we can assume that the packet data has no
alignment. This is expressed by casting the packet-object pointer to a pointer
of the new packed helper struct 'Packed_uint16' that contains only a single
uint16_t member before handing it over to the checksum function (instead of
casting it to a uint16_t pointer).
Ref #4109
The NAT feature of the NIC router used to prefer re-using source ports that
have been freed recently. From an external server's perspective, if a client
dies and restarts, chances are high that the new connect arrives with the same
source-IP/source-port as the old connection. The server has to forcefully reset
the connection. If that happens a lot, the server may even start to ignore
further connections from this IP/port combination for a while as a mitigation.
This patch adds a continuous counter feature that makes sure that every new
port allocation will increment and result in a port that hasn't been used for a
long time.
The NAT feature of the nic_router is now more in line with RFC 6056 chapter 4.
Ref #4086
pthread.0 acquires a write buffer mutex and calls potentially
blocking fs operations. The EP thread handles session requests and tries to
acquire the same write buffer lock. IO progress events for pthread.0 are
handled by the EP thread, which however is blocking on the write buffer mutex.
The commit uses two write buffers, one which is filled by the EP and a second
which is used by pthread.0. The two buffers are swapped protected by a mutex
without invoking blocking fs operations.
Issue #4095
The exec_terminal generates a config report which is used as input ROM for
sandbox/init, which does not support an "<empty>" node.
An empty config node is empty, without an node.
Issue #4095
Was still using the event_filter.config from drivers_interactive-pc
although a dedicated file is present in the raw archive.
The fix is just for consistency reasons, as sculpt manager is generating the
event_filter.config anyway.
KEY_UNKNOWN is a collective symbols for all unknown keycodes.
Remapping thus requires iterating through all corresponding codes
instead of only applying the policy to the first match.
Issue genodelabs#4069
This patch increases the RAM quota of the top-level nitpicker instance
to 12 MiB so that resize operations can be buffered for resolutions up
to 2560x1080. It mutes diagnostic messages of the form "Warning: Gui
(...) not enough RAM to preserve buffer content during resize" and
improves the window-resize experience.
With this patch, the user is able to re-gain access to the inspect view
by toggling the inspect button of a file system unrelated to the failed
USB storage device.
Fixes#4090
