At some point in the past few years, binutils became more aggressive
at removing unused symbols. To function as a symbol requirement, a
relocation record must now be in a section marked with @progbits and
must not be in a section which gets discarded during the link (either
via --gc-sections or via /DISCARD/).
Update REQUIRE_SYMBOL() to generate relocation records meeting these
criteria. To minimise the impact upon the final binary size, we use
existing symbols (specified via the REQUIRING_SYMBOL() macro) as the
relocation targets where possible. We use R_386_NONE or R_X86_64_NONE
relocation types to prevent any actual unwanted relocation taking
place. Where no suitable symbol exists for REQUIRING_SYMBOL() (such
as in config.c), the macro PROVIDE_REQUIRING_SYMBOL() can be used to
generate a one-byte-long symbol to act as the relocation target.
If there are versions of binutils for which this approach fails, then
the fallback will probably involve killing off REQUEST_SYMBOL(),
redefining REQUIRE_SYMBOL() to use the current definition of
REQUEST_SYMBOL(), and postprocessing the linked ELF file with
something along the lines of "nm -u | wc -l" to check that there are
no undefined symbols remaining.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow fc_ulp_decrement() to guarantee to fc_peer_decrement() that the
peer reference remains valid for the duration of the call, by ensuring
that ulp->peer remains valid while ulp is valid.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Allow link examination methods to safely assume that their
self-reference remains valid for the duration of the method call.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The FCP command reference number is intended to be used for
controlling precise delivery of FCP commands, rather than being an
essentially arbitrary tag field (as with iSCSI and SRP).
Use the Fibre Channel local exchange ID as the tag for FCP commands,
instead of the FCP command reference. The local exchange ID does not
appear within the FCP IU itself, but does appear within the FC frame
header; debug traces can therefore still be correlated with packet
captures.
Reported-by: Hadar Hen Zion <hadarh@mellanox.co.il>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
The response to a received FLOGI should probably be sent to the peer
port ID assigned as a result of the WWPN comparison.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Add support for Fibre Channel ports, peers, and upper-layer protocols,
and for Fibre Channel extended link services.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown