[timer] Rewrite the 8254 Programmable Interval Timer support
The 8254 timer code (used to implement udelay()) has an unknown
provenance. Rewrite this code to avoid potential licensing
uncertainty.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
As with memcpy(), we can reduce the code size (by an average of 0.2%)
by giving the compiler more visibility into what memset() is doing,
and by avoiding the "rep" prefix on short fixed-length sequences of
string operations.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some of the C library string functions have an unknown provenance.
Reimplement all such functions to avoid potential licensing
uncertainty.
Remove the inline-assembler versions of strlen(), memswap(), and
strncmp(); these save a minimal amount of space (around 40 bytes in
total) and are not performance-critical.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Provide generic framework for refilling receive endpoints
Provide a generic framework for allocating, refilling, and optionally
recycling I/O buffers used by bulk IN and interrupt endpoints.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[build] Apply the "-fno-PIE -nopie" workaround only to i386 builds
Hardened versions of gcc default to building position-independent
code, which breaks our i386 build. Our build process therefore
detects such platforms and automatically adds "-fno-PIE -nopie" to the
gcc command line.
On x86_64, we choose to build position-independent code (in order to
reduce the final binary size and, in particular, the number of
relocations required for UEFI binaries). The workaround therefore
breaks the build process for x86_64 binaries on such platforms.
Fix by moving the workaround to the i386-specific portion of the
Makefile.
Reported-by: Jan Kundrát <jkt@kde.org>
Debugged-by: Jan Kundrát <jkt@kde.org>
Debugged-by: Marin Hannache <git@mareo.fr>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
UEFI binaries may be relocated to any location within the 64-bit
address space. We compile as position-independent code with hidden
visibility, which should force all relocation records to be either
PC-relative (in which case no PE relocations are required) or full
64-bit relocations. There should be no R_X86_64_32 relocation
records, since that would imply an invalid assumption that code could
not be relocated above 4GB.
Remove support for R_X86_64_32 relocation records from util/elf2efi.c,
so that any such records result in a build failure rather than a
potential runtime failure.
Reported-by: Jan Kundrát <jkt@kde.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
When building hvmloader for Xen tools the iPXE objects are also linked
into the binary. Unfortunately the linker will place them in the
order found in the archive. Since this order is random the resulting
hvmloader binary differs when it was built from identical sources but
on different build hosts. To help with creating a reproducible binary
the elements in blib.a must simply be sorted before passing them to
$(AR).
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Handle port status changes received after failing to find a driver
Commit a60f2dd ("[usb] Try multiple USB device configurations")
changed the behaviour of register_usb() such that if no drivers are
found then the device will be closed and the memory used will be
freed.
If a port status change subsequently occurs while the device is still
physically attached, then usb_hotplug() will see this as a new device
having been attached, since there is no device recorded as being
currently attached to the port. This can lead to spurious hotplug
events (or even endless loops of hotplug events, if the process of
opening and closing the device happens to generate a port status
change).
Fix by using a separate flag to indicate that a device is physically
attached (even if we have no corresponding struct usb_device).
Reported-by: Dan Ellis <Dan.Ellis@displaylink.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[build] Use PRODUCT_SHORT_NAME for end-user visible strings
Use PRODUCT_SHORT_NAME instead of a hardcoded "iPXE" for strings which
are typically shown in the user interface.
Note that this only allows for customisation of the user interface.
Where the "iPXE" string serves a technical purpose (such as in the
HTTP User-Agent), the string cannot be customised.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[xhci] Delay after (possibly) forcing port link state to RxDetect
Some xHCI controllers (observed with a Renesas Electronics PCIe USB3
card) seem to require a delay after forcing the link state of USB3
ports to RxDetect. Omitting this delay causes strange behaviour
including system lockups.
Add an unconditional 20ms delay after writing the port link states.
This seems to be sufficient to avoid the problem.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[usb] Allow usb_stream() to enforce a terminating short packet
Some USB endpoints require that a short packet be used to terminate
transfers, since they have no other way to determine message
boundaries. If the message length happens to be an exact multiple of
the USB packet size, then this requires the use of an additional
zero-length packet.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
USB Communications Device Class devices may use a union functional
descriptor to group several interfaces into a function.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Iterate over a USB device's available configurations until we find one
for which we have working drivers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some protocols (such as ARP) may modify the received packet and re-use
the same I/O buffer for transmission of a reply. To allow this,
reserve sufficient headroom at the start of each received packet
buffer for our transmit datapath headers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[pxe] Maintain a queue for received PXE UDP packets
Some devices return multiple packets in a single poll. Handle such
devices gracefully by enqueueing received PXE UDP packets (along with
a pseudo-header to hold the IPv4 addresses and port numbers) and
dequeueing them on subsequent calls to PXENV_UDP_READ.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[tftp] Explicitly abort connection whenever parent interface is closed
Fetching the TFTP file size is currently implemented via a custom
"tftpsize://" protocol hack. Generalise this approach to instead
close the TFTP connection whenever the parent data-transfer interface
is closed.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some devices have a very small number of internal buffers, and rely on
being able to pack multiple packets into each buffer. Using 2048-byte
buffers on such devices produces throughput of around 100Mbps. Using
a small number of much larger buffers (e.g. 32kB) increases the
throughput to around 780Mbps. (The full 1Gbps is not reached because
the high RTT induced by the use of multi-packet buffers causes us to
saturate our 256kB TCP window.)
Since allocation of large buffers is very likely to fail, allocate the
buffer set only once when the device is opened and recycle buffers
immediately after use. Received data is now always copied to
per-packet buffers.
If allocation of large buffers fails, fall back to allocating a larger
number of smaller buffers. This will give reduced performance, but
the device will at least still be functional.
Share code between the interrupt and bulk IN endpoint handlers, since
the buffer handling is now very similar.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow drivers to specify a supported PCI class code. To save space in
the final binary, make this an attribute of the driver rather than an
attribute of a PCI device ID list entry.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[hyperv] Require support for VMBus version 3.0 or newer
We require the ability to disconnect from and reconnect to VMBus; if
we don't have this then there is no (viable) way for a loaded
operating system to continue to use any VMBus devices. (There is also
a small but non-zero risk that the host will continue to write to our
interrupt and monitor pages, since the VMBUS_UNLOAD message in earlier
versions is essentially a no-op.)
This requires us to ensure that the host supports protocol version 3.0
(VMBUS_VERSION_WIN8_1). However, we can't actually _use_ protocol
version 3.0, since doing so causes an iSCSI-booted Windows Server 2012
R2 VM to crash due to a NULL pointer dereference in vmbus.sys.
To work around this problem, we first ensure that we can connect using
protocol v3.0, then disconnect and reconnect using the oldest known
protocol.
This deliberately prevents the use of the iPXE native Hyper-V drivers
on older versions of Hyper-V, where we could use our drivers but in so
doing would break the loaded operating system.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[rndis] Ignore start-of-day RNDIS_INDICATE_STATUS_MSG with status 0x40020006
Windows Server 2012 R2 generates an RNDIS_INDICATE_STATUS_MSG with a
status code of 0x4002006. This status code does not appear to be
documented anywhere within the sphere of human knowledge.
Explicitly ignore this status code in order to avoid unnecessarily
cluttering the display when RNDIS debugging is enabled.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[hyperv] Assume that VMBus xfer page ranges correspond to RNDIS messages
The (undocumented) VMBus protocol seems to allow for transfer
page-based packets where the data payload is split into an arbitrary
set of ranges within the transfer page set.
The RNDIS protocol includes a length field within the header of each
message, and it is known from observation that multiple RNDIS messages
can be concatenated into a single VMBus message.
iPXE currently assumes that the transfer page range boundaries are
entirely arbitrary, and uses the RNDIS header length to determine the
RNDIS message boundaries.
Windows Server 2012 R2 generates an RNDIS_INDICATE_STATUS_MSG for an
undocumented and unknown status code (0x40020006) with a malformed
RNDIS header length: the length does not cover the StatusBuffer
portion of the message. This causes iPXE to report a malformed RNDIS
message and to discard any further RNDIS messages within the same
VMBus message.
The Linux Hyper-V driver assumes that the transfer page range
boundaries correspond to RNDIS message boundaries, and so does not
notice the malformed length field in the RNDIS header.
Match the behaviour of the Linux Hyper-V driver: assume that the
transfer page range boundaries correspond to the RNDIS message
boundaries and ignore the RNDIS header length. This avoids triggering
the "malformed packet" error and also avoids unnecessary data copying:
since we now have one I/O buffer per RNDIS message, there is no longer
any need to use iob_split().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Empirical observation suggests that 32 is a sensible size to minimise
the number of deferred packet transmissions without overflowing the
VMBus transmit ring buffer.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown