Command implementations tend to include a substantial amount of common
boilerplate code revolving around the parsing of command-line options
and arguments. This increases the size cost of each command.
Introduce an option-parsing library that abstracts out the common
operations involved in command implementations. This enables the size
of each individual command to be reduced, and also enhances
consistency between commands.
Total size of the library is 704 bytes, to be amortised across all
command implementations.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[netdevice] Allow per-device receive queue processing to be frozen
Several use cases (e.g. the UNDI API and the EFI SNP API) require
access to the raw network device receive queue, and so currently use
manual calls to netdev_poll() on a specific network device in order to
prevent received packets from being processed by the network stack.
As an alternative, provide a flag that allows receive queue processing
to be frozen on a per-device basis. When receive queue processing is
frozen, packets will be enqueued as normal, but will not be
automatically dequeued and passed up the network stack.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[undi] Support underlying UNDI devices that don't support interrupts
Some network cards do not generate interrupts when operated via the
UNDI API. Allow for this by waiting for the ISR to be triggered only
if the PXE stack advertises that it supports interrupts. When the PXE
stack does not advertise interrupt support, we skip the call to
PXENV_UNDI_ISR_IN_START and just poll the device using
PXENV_UNDI_ISR_IN_PROCESS. This matches the observed behaviour of at
least one other PXE NBP (emBoot's winBoot/i), so there is a reasonable
chance of this working.
Originally-implemented-by: Muralidhar Appalla <Muralidhar.Appalla@emulex.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Provide a "hexhyp" setting type, which functions identically to the
"hex" setting type except that it uses a hyphen instead of a colon as
the byte delimiter.
For example, if ${mac} expands to "52:54:00:12:34:56", then
${mac:hexhyp} will expand to "52-54-00-12-34-56".
Originally-implemented-by: Jarrod Johnson <jarrod.b.johnson@gmail.com>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[forcedeth] Exit poll() as early as possible if no work to do
Fix incorrect authorship attribution on commit f122515 ("[forcedeth]
Exit poll() as early as possible if no work to do").
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[list] Fix typographical error from previous commit
Fix typographical error from commit ea631f6 ("[list] Add
list_first_entry()"). The symptom was PXELINUX 3.86 causing a stack
overflow under VMware.
Tested-by: Shao Miller <shao.miller@yrdsb.edu.on.ca>
Signed-off-by: Shao Miller <shao.miller@yrdsb.edu.on.ca>
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>
[fc] Hold reference to peers and ULPs while calling fc_link_examine()
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>
[retry] Process at most one timer's expiry in each call to retry_step()
Calling a timer's expiry method may cause arbitrary consequences,
including arbitrary modifications of the list of retry timers.
list_for_each_entry_safe() guards against only deletion of the current
list entry; it provides no protection against other list
modifications. In particular, if a timer's expiry method causes the
subsequent timer in the list to be deleted, then the next loop
iteration will access a timer that may no longer exist.
This is a particularly nasty bug, since absolutely none of the
list-manipulation or reference-counting assertion checks will be
triggered. (The first assertion failure happens on the next iteration
through list_for_each_entry(), showing that the list has become
corrupted but providing no clue as to when this happened.)
Fix by stopping traversal of the list of retry timers as soon as we
hit an expired timer.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[malloc] Avoid immediately clobbering reference count when freeing memory
Rearrange the fields in struct memory_block (without altering
MIN_MEMBLOCK_SIZE) so that the "count" field of a reference-counted
object is left intact when the memory containing the object is freed.
This allows for the possibility of detecting reference-counting errors
such as double-freeing.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[refcnt] Check reference validity on each use of ref_get() and ref_put()
Check that the reference count is valid (i.e. non-negative) on each
call to ref_get() and ref_put(), using an assert() at the point of
use.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[malloc] Use list_for_each_entry_safe() when we may delete a list entry
free_memblock() currently uses list_for_each_entry() to iterate over
the free list, and may delete an entry over which it iterates. While
there is no way that the deleted list entry could be overwritten
before we reference it, this does rely upon list_del() leaving the
"next" pointer intact, which is not guaranteed. Discovered while
tracking down a list-corruption bug (as a result of having modified
list_del() to sanitise the deleted list entry).
Fix by using list_for_each_entry_safe().
Signed-off-by: Michael Brown <mcb30@ipxe.org>
There are several points in the iPXE codebase where
list_for_each_entry() is (ab)used to extract only the first entry from
a list. Add a macro list_first_entry() to make this code easier to
read.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Functions that instantiate objects generally own one reference to the
object being created. The error paths must therefore usually call
ref_put() to release this reference.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
For some install-to-SAN scenarios, the OS needs to be able to reboot
to reread the partition table. On this second boot attempt, the SAN
disk will not be empty and so iPXE will attempt to boot from it,
rather than falling back to the OS' installation media.
Work around this problem by introducing the "skip-san-boot" option,
similar in spirit to "keep-san".
Modified-by: Michael Brown <mcb30@ipxe.org>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Improve the visibility of error messages by removing the redundant
final printing of the URL being booted.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[scsi] Wait for a successful TEST UNIT READY command
Some SCSI targets (observed with an EMC CLARiiON Fibre Channel target)
will not respond to commands correctly until a TEST UNIT READY has
been issued. In particular, a READ CAPACITY (10) command will return
with a success status, but no capacity data.
Fix by issuing a TEST UNIT READY command automatically, and delaying
further SCSI commands until the TEST UNIT READY has succeeded.
Reported-by: Hadar Hen Zion <hadarh@mellanox.co.il>
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[fc] Do not use the command reference number in FCP_CMND IUs
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>
[hci] Use http://ipxe.org/<errno> instead of raw error numbers
Users tend to gloss over cryptic-looking error messages such as
"Boot failed: Exec format error (Error 0x2e852001)"
In particular, users tend not to report the error number, which is the
single most useful piece of diagnostic information in an iPXE error
message. Try replacing the "Error 0x2e852001" portion with a URL,
giving
"Boot failed: Exec format error (http://ipxe.org/2e852001)"
in the hope that users will, upon seeing something that is
recognisably a URL, try viewing it in a web browser. Such users will
be greeted by a web page containing a more detailed description of the
error (automatically generated from the einfo text), including links
to each line of code that might generate the error, and a section for
additional user-contributed notes. At the time of writing, a user who
visits http://ipxe.org/2e852001 would see a note saying
"This error usually indicates that the SAN disk is empty, and does
not yet contain a bootable operating system."
which may be more useful than "Exec format error (Error 0x2e852001)".
Signed-off-by: Michael Brown <mcb30@ipxe.org>
[iscsi] Ensure ISID is consistent within an iSCSI session
Commit 5f4ab0d ("[iscsi] Randomise a portion of the ISID to force new
session instantiation") introduced a regression by randomising the
ISID on each call to iscsi_start_login(), which may be called more
than once per connection, rather than on each call to
iscsi_open_connection(), which is guaranteed to be called only once
per connection. This is incorrect behaviour that causes our
connection to be rejected by some iSCSI targets (observed with a
COMSTAR target under OpenSolaris).
Fix by generating the ISID in iscsi_open_connection(), and storing the
randomised ISID as part of the session state.
Signed-off-by: Michael Brown <mcb30@ipxe.org>
Michael Brown