The 'file_size' type denotes the size of files on disk in bytes. On
32-bit architectures it is larger than the size_t, which refers to
in-memory object sizes.
Whereas the use of 'file_size' is appropriate for ftruncate and seek, it
is not a suitable type for the parameters of read/write operations
because those operations refer to in-memory buffers.
This patch replaces the use of 'file_size' by size_t. However, since it
affects all sites where the read/write interface is uses, it takes the
opportunity to replace the C-style (pointer, size) arguments by
'Byte_range_ptr' and 'Const_byte_range_ptr'.
Issue #4706
Prior to this change the libdrm Lima implementation supported the
creation of multiple contexts where each context, however, was
treated as the same client like it was done in the Lima driver
itself.
With this commit each context becomes its own client while the
main context always performs all buffer object related allocation
and the other context import each needed BO before submitting.
Fixes#4760.
Sync file-descriptors a purely virtual and are not known by the libc and
should be only accessed by 'drm_poll'. To prevent accidental access move
them to range never used by the libc fd allocator.
Issue #4760.
* 'map_buffer', GTT mappings are currently not used by Iris
* 'set_tiling', tiling is currently not used by Iris because there are
no GTT mappings
issue #4713
lwip uses a sophisticated reference-counting scheme in chains of pbufs,
which the former manual implementation of read() for TCP data broke.
Using pbuf_free_header() keeps the chain intact and also relieves our
implementation from the burden of "offset" maintenance.
Fixes#4722
Some USB devices (e.g., webcams) fail to deliver their configuration
descriptor early after power-up. Testing revealed that retrying the
requests usually succeeds on second or third attempt.
Fixes#4739
The old 'Io_response_handler::io_progress_response' interface has been
replaced by the 'Vfs::Env::User::wakeup_vfs_user' (issue #4697). The
remaining 'read_ready_response' method is now hosted in the
appropriately named 'Read_ready_response_handler'.
Issue #4706
The 'blocked_handles' queue was used to notify the VFS user via the
'io_progress_response' mechanism. This is now covered by the
'wakeup_vfs_user' interface introduced in issue #4697.
Issue #4706
By adding a 'write_ready' interface following the lines of the existing
'read_ready', VFS plugins become able to propagate the (de-)saturation
of I/O buffers to the VFS user. This information is important when using
a non-blocking file descriptor for writing into a TCP socket. Once the
application observes EAGAIN, it expects a subsequent 'select' call to
return as soon as new I/O buffer space becomes available.
Before this patch, the select call would always return under this
condition, causing an unnecessarily busy write loop.
Issue #4697
The new interface is meant to replace the 'Vfs::Io_response_handler'.
In contrast to the 'Io_response_handler', which had to be called
on a 'Vfs_handle', the new interface does not require any specific
'Vfs_handle'. It is merely meant to prompt the VFS user (like the libc)
to re-attempt stalled I/O operations but it does not provide any
immediate hint, about which of the handles have become ready for
reading/writing.
Issue #4697
This patch removes the 'Insufficient_buffer' exception by returning the
WRITE_ERR_WOULD_BLOCK result value instead. It also eliminates the
superfluous WRITE_ERR_AGAIN and WRITE_ERR_INTERRUPT codes.
Issue #4697
The original size of 16K impedes the batched processing of network
packets. Changing the value to 256K reduces the number of context
switches when downloading large files and thereby improves the
throughput by more than 25% (base-hw on qemu_x86_64, using fetchurl
to download a file of 100 MiB via the NIC router from lighttpd).
Issue #4697
This patch fosters the batching of network packets transferred by the
lwIP stack over the NIC connection. It replaces the eager submission of
the packet-stream's data-flow signals by explicit wakeup notifications.
The commit also increases the NIC session's buffer size from 128 to 1024
packets.
Issue #4697
Since the lwip library is used only by the vfs_lwip plugin, this patch
moves the Genode-specific support code local to the VFS plugin, easing
further simplification and allowing for a tighter integration with the
VFS plugin.
The recipes for api/lwip and src/vfs_lwip stay separate as both parts
use different licenses.
Issue #4697
This patch facilitates the batching of I/O operations in the VFS library
by replacing the implicit wakeup of remote peer (via the traditional
packet-stream interface like 'submit_packet') by explicit wakeup
signalling.
The wakeup signalling is triggered not before the VFS user settles down.
E.g., for libc-based applications, this is the case if the libc goes
idle, waiting for external I/O.
In the case of a busy writer to a non-blocking file descriptor or socket
(e.g., lighttpd), the remote peers are woken up once a write operation
yields an out-count of 0.
The deferring of wakeup signals is accommodated by the new 'Remote_io'
mechanism (vfs/remote_io.h) that is designated to be used by all VFS
plugins that interact with asynchronous Genode services for I/O.
Issue #4697
This test reveals the patters of the batching of consecutive write
operations on a file-system session. It issues 100 writes of one byte
each, which should ideally result in large batches of operations
submitted to the file-system session at once.
The run script performs the write operations through a chain of two VFS
servers, thereby exercising the write batching of both the libc and the
intermediate VFS server.
Issue #4697
