Under some circumstances (e.g. if iPXE itself is booted via iSCSI, or
after an unclean reboot), the backend may not be in the expected
InitWait state when iPXE starts up.
There is no generic reset mechanism for Xenbus devices. Recent
versions of xen-netback will gracefully perform all of the required
steps if the frontend sets its state to Initialising. Older versions
(such as that found in XenServer 6.2.0) require the frontend to
transition through Closed before reaching Initialising.
Add a reset mechanism for netfront devices which does the following:
- read current backend state
- if backend state is anything other than InitWait, then set the
frontend state to Closed and wait for the backend to also reach
Closed
- set the frontend state to Initialising and wait for the backend to
reach InitWait.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Using version 1 grant tables limits guests to using 16TB of grantable
RAM, and prevents the use of subpage grants. Some versions of the Xen
hypervisor refuse to allow the grant table version to be set after the
first grant references have been created, so the loaded operating
system may be stuck with whatever choice we make here. We therefore
currently use version 2 grant tables, since they give the most
flexibility to the loaded OS.
Current versions (7.2.0) of the Windows PV drivers have no support for
version 2 grant tables, and will merrily create version 1 entries in
what the hypervisor believes to be a version 2 table. This causes
some confusion.
Avoid this problem by attempting to use version 1 tables, since
otherwise we may render Windows unable to boot.
Play nicely with other potential bootloaders by accepting either
version 1 or version 2 grant tables (if we are unable to set our
requested version).
Note that the use of version 1 tables on a 64-bit system introduces a
possible failure path in which a frame number cannot fit into the
32-bit field within the v1 structure. This in turn introduces
additional failure paths into netfront_transmit() and
netfront_refill_rx().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The behavior observed in the Apple EFI (1.10) RecieveFilters() call
is:
- failure if any of the PROMISCUOUS or MULTICAST filters are
included
- success if only UNICAST is included, however the result is
UNICAST|BROADCAST
- success if only UNICAST and BROADCAST are included
- if UNICAST, or UNICAST|BROADCAST are used, but the previous call
tried (and failed) to set UNICAST|BROADCAST|MULTICAST, then the
result is UNICAST|BROADCAST|MULTICAST
Work around this apparently broken SNP implementation by trying
RecieveFilterMask, then falling back to UNICAST|BROADCAST|MULTICAST,
then UNICAST|BROADCAST, and finally UNICAST.
Modified-by: Michael Brown <mcb30@ipxe.org>
Tested-by: Curtis Larsen <larsen@dixie.edu>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Open device path protocol only at point of use
Some EFI 1.10 systems (observed on an Apple iMac) do not allow us to
open the device path protocol with an attribute of
EFI_OPEN_PROTOCOL_BY_DRIVER and so we cannot maintain a safe,
long-lived pointer to the device path. Work around this by instead
opening the device path protocol with an attribute of
EFI_OPEN_PROTOCOL_GET_PROTOCOL whenever we need to use it.
Debugged-by: Curtis Larsen <larsen@dixie.edu>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Reset multicast filter list when setting SNP receive filters
According to the UEFI specification, the MCastFilter parameter (which
we currently pass as NULL, along with a zero MCastFilterCnt) is
optional only if ResetMCastFilter is true.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Dump existing openers when we are unable to open a protocol
Dump the existing openers of a protocol whenever we are unable to open
a protocol using attributes of BY_DEVICE, EXCLUSIVE, or
BY_CHILD_CONTROLLER.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[efi] Use efi_handle_name() instead of efi_devpath_text() where applicable
Using efi_devpath_text() is marginally more efficient if we already
have the device path protocol available, but the mild increase in
efficiency is not worth compromising the clarity of the pattern:
DBGC ( device, "THING %p %s ...", device, efi_handle_name ( device ) );
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Rewrite the SNP NIC driver to use non-blocking and deferrable
transmissions, to provide link status detection, to provide
information about the underlying (PCI) hardware device, and to avoid
unnecessary I/O buffer allocations during receive polling.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The VF might not have assigned a MAC address upon startup, and will
end up with a random MAC address during probe(). With this patch the
MAC address can be changed later on.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
If the VF doesn't have a MAC address assigned we should create a
random MAC address.
Signed-off-by: Hannes Reinecke <hare@suse.de>
Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The iBFT includes an "origin" field to indicate the source of the IP
address. We use the heuristic of assuming that the source should be
"manual" if the IP address originates directly from the network device
settings block, and "DHCP" otherwise. This is an imperfect guess, but
is likely to be correct in most common situations.
Originally-implemented-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Parse the sense data to extract the reponse code, the sense key, the
additional sense code, and the additional sense code qualifier.
Originally-implemented-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
As of commit d28bb51 ("[tcp] Defer sending ACKs until all received
packets have been processed"), increasing the RX ring size will
increase the number of received packets per transmitted ACK (since
each poll will process up to one complete receive ring). Under KVM,
this can make a substantial (up to ~200%) difference to the overall
download speed, since transmissions are very expensive.
Increase the ring fill level from four to eight packets: this
increases the download speed by around 50% at a cost of around 8kB of
heap space. Further speedups are possible by increasing the ring size
further, but it would be preferable to find alternative methods which
do not use noticeable amounts of heap space.
Tested-by: Robin Smidsrød <robin@smidsrod.no>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Exclude time spent in hypervisor from profiling
When profiling, exclude any time spent inside the hypervisor
responding to our MMIO accesses. This substantially reduces the
variance accumulated on many other profilers.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Inside a virtual machine, writing the RX ring tail pointer may incur a
substantial overhead of processing inside the hypervisor. Minimise
this overhead by writing the tail pointer once per batch of
descriptors, rather than once per descriptor.
Profiling under qemu-kvm (version 1.6.2) shows that this reduces the
amount of time taken to refill the RX descriptor ring by around 90%.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Operations which are negligible on physical hardware (such as issuing
a posted write to the transmit ring tail register) may involve
substantial amounts of processing within the hypervisor if running in
a virtual machine.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[intel] Avoid completely filling the TX descriptor ring
It is unclear from the datasheets whether or not the TX ring can be
completely filled (i.e. whether writing the tail value as equal to the
current head value will cause the ring to be treated as completely
full or completely empty). It is very plausible that this edge case
could differ in behaviour between real hardware and the many
implementations of an emulated Intel NIC found in various virtual
machines. Err on the side of caution and always leave at least one
ring entry empty.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
On an Asus Z87-K motherboard with an onboard 8168 NIC, booting into
Windows 7 and then warm rebooting into iPXE results in a broken RX
datapath: packets can be transmitted successfully but garbage is
received. A cold reboot clears the problem.
A dump of the PHY registers reveals only one difference: in the
failure case the bits ADVERTISE_PAUSE_CAP and ADVERTISE_PAUSE_ASYM are
cleared. Explicitly setting these bits does not fix the problem.
A dump of the MAC registers reveals a few differences, of which the
most obvious culprit is the undocumented bit 24 of the Receive
Configuration Register (RCR), which is set in the failure case.
Explicitly clearing this bit does fix the problem.
Reported-by: Sebastian Nielsen <ipxe@sebbe.eu>
Reported-by: Oliver Rath <rath@mglug.de>
Debugged-by: Sebastian Nielsen <ipxe@sebbe.eu>
Tested-by: Sebastian Nielsen <ipxe@sebbe.eu>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[settings] Explicitly separate the concept of a completed fetched setting
The fetch_setting() family of functions may currently modify the
definition of the specified setting (e.g. to add missing type
information). Clean up this interface by requiring callers to provide
an explicit buffer to contain the completed definition of the fetched
setting, if required.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Give tap devices a meaningful name, and avoid segmentation faults when
attempting to retrieve ${net0/bustype} by assigning a new bus type for
tap devices.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Prevent the card from flagging packets of 1518 bytes length as
overlength.
This fixes the High-MTU loopback test.
Signed-off-by: Thomas Miletich <thomas.miletich@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The 3c90x B and C revisions support rounding up the packet length to a
specific boundary. Disable this feature to avoid overlength packets.
This fixes the loopback test.
Signed-off-by: Thomas Miletich <thomas.miletich@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[3c90x] Stall upload engine before setting RX ring address
According to the 3c90x datasheet we have to stall the upload (receive)
engine before setting the receive ring address.
Signed-off-by: Thomas Miletich <thomas.miletich@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Some hardware (observed with an onboard RTL8168) will erroneously
report a buffer overflow error if the received packet exactly fills
the receive buffer.
Fix by adding an extra four bytes of padding to each receive buffer.
Debugged-by: Thomas Miletich <thomas.miletich@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown