It was broken by design and unused for years due to conflicts between
different threads, fighting for the same set of mailbox registers, not
designed for multiple requests at a time. So either request has to be
synchronous and spin under the lock, or it should be sent asynchronously
through the queues as Mailbox Command IOCB or some other way.
This removes any OS specifics from the wait code, so it can be inlined.
Qlogic chips store S/G lists in the same queue as requests themselves. In
the worst case 1MB I/O may require up to 52 IOCBs, that means queue of 1024
IOCBs can store only 19 of such requests. The increase reduces chances of
overflow, while we should be able to afford additional 512KB of RAM per HBA.
The Linux driver uses comparable numbers.
While there, decouple ATIO queue size from response queue size. There is
no reason for them to be equal.
- Make isp_start() to set all the IOCB fields aside of S/G list, removing
extra information from isp_send_cmd(), now only doing S/G lists and sending.
- Turn DMA setup/free from being card and PCI-specific into OS-specific,
instead add new card-specific method for isp_send_cmd(). Previously this
function was a monster handling all the cards.
- Remove double error code translation.
This removes 288KB (36%) of the driver code and zillions of hacks and
workarounds, making single driver uniformly support several different
generations of hardware interfaces, not counting minor card variations.
After years of the hopeless fight, I don't think it worth to continue
support for hardware obsolete for 15-20 years. Instead much cleaner
now code should allow to move forward toward better locking, multiple
queues and other cool features.
All the remaining Qlogic cards starting from 4Gb 24xx to 32Gb 27xx use
the same hardware/firmware interface with minor incremental improvements,
so it seems to be a good new starting point. Except one PCI-X model all
all of them are PCIe and so still usable in modern systems.
Discussed with: ken, scottl, jpaetzel, imp
Relnotes: yes
Ecmd memory is not directly related to the request queue, only referenced
from it sometimes in target mode. Separate allocation should be easier
in case of fragmented memory and can be skipped when target is not built.
MFC after: 1 month
SAM-3 specification introduced concept of Task Priority, that was renamed
to Command Priority in SAM-4, and supported by all modern SCSI transports.
It provides 15 levels of relative priorities: 1 - highest, 15 - lowest and
0 - default. SAT specification for SATA devices translates priorities 1-3
into NCQ high priority.
This change adds new "priority" field into empty spots of struct ccb_scsiio
and struct ccb_accept_tio of CAM and struct ctl_scsiio of CTL. Respective
support is added into iscsi(4), isp(4), mpr(4), mps(4) and ocs_fc(4) drivers
for both initiator and where applicable target roles. Minimal support was
added to CTL to receive the priority value from different frontends, pass it
between HA controllers and report in few places.
This patch does not add consumers of this functionality, so nothing should
really change yet, since the field is still set to 0 (default) on initiator
and not actively used on target. Those are to be implemented separately.
I've confirmed priority working on WD Red SATA disks connected via mpr(4)
and properly transferred to CTL target via iscsi(4), isp(4) and ocs_fc(4).
While there, added missing tag_action support to ocs_fc(4) initiator role.
MFC after: 1 month
Relnotes: yes
Sponsored by: iXsystems, Inc.
Mainly focus on files that use BSD 2-Clause license, however the tool I
was using misidentified many licenses so this was mostly a manual - error
prone - task.
The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.
Let firmware do its best first, and if it can't, try software recovery.
I would remove software timeout handler completely, but found bunch of
complains on command timeout on sparc64 mailing list few years ago, so
better be safe in case of interrupt loss.
MFC after: 2 weeks
For 24xx and above use 2 vectors (default and response queue).
For 26xx and above use 3 vectors (default, response and ATIO queues).
Due to global lock interrupt hardlers never run simultaneously now, but
at least this allows to save one regitster read per interrupt.
MFC after: 2 weeks
It was implemented to reduce context switches when uploading firmware to
card's RAM. But this mechanism is not used last 10 years since all mbox
operations are now polled, and it was never used for cards produced in
last 15 years. Newer cards can use DMA to upload firmware.
MFC after: 2 weeks
This change fixes DMA resource leak on driver unload. Also it removes
DMA resources allocation for hardcoded number of requests before fetching
the real number from firmware. Also it prepares ground for more flexible
IRQs allocation according to firmware capabilities.
MFC after: 2 weeks
Its more important for SPI HBAs, as they don't support CDBs above 12 bytes.
The new error code makes CAM to fall back to alternative commands.
MFC after: 2 weeks
- Move private data about ATIOs/INOTs from per-LUN to per-channel data.
This allows active commands to continue operation after LUN destruction.
This also simplifies lookup of the data by tag in some situations.
- Unify three restart_queue processing implementations.
- Complete all ATIOs from restart_queue on LUN disable.
- Delete ATIO private data when command completed or aborted, not depending
on the ATIO being requeued, that was ugly hack and could never happen. CAM
should always call ether XPT_CONT_TARGET_IO with status or XPT_ABORT.
- Implement XPT_ABORT for queued ATIOs/INOTs to allow CAM do graceful
shutdown, not depending on LUN disable, as it is done in ahd(4)/targ(4).
- Unify isp_endcmd() arguments to make it more usable in generic code.
- Remove never really used LUN state reference counter.
MFC after: 2 weeks
All resources lack of which may put CTIO into the queue are either
per-channel or potentially per-queue, but none of them are per-LUN.
This is a first step to fix live LUN disabling. Before this change
any CTIOs held in a queue in time of disabling were just leaked.
MFC after: 2 weeks
Usually IOCBs should be put on queue for asynchronous processing and should
not require additional DMA memory. But there are some cases like aborts and
resets that for external reasons has to be synchronous. Give those cases
separate 2*64 byte DMA area to decouple them from other DMA scratch area
users, using it for asynchronous requests.
This is cosmetics that simplifies identification of new ports on FC switch.
It would be good to use target name from CTL here instead of hostname, but
it is not passed here through CAM now.
MFC after: 2 weeks
- Make scan aborted by event restart immediately and infinitely.
- Improve handling of some loop events from firmware.
- Remove loop down timer, adding its functionality to scanner thread.
- Some more unification and simplification.
Hacks to enable target mode there complicated code, while didn't really
work. And for outdated hardware fixing it is not really interesting.
Initiator mode tested with Qlogic 1080 adapter is still working fine.
Now 24xx and above chips support full 8-byte LUN address space.
Older FC chips may support up to 16K LUNs when firmware allows.
Tested in both initiator and target modes for 23xx, 24xx and 25xx.
FC port database code already notifies CAM about all devices. Additional
full scan is just a waste of time, that by definition won't find anything
that is not present in port database.
The Command Reference Number is used for precise delivery of
commands, and is part of the FC-Tape functionality set. (This is
only enabled for devices that support precise delivery of commands.)
It is an 8-bit unsigned number that increments from 1 to 255. The
commands sent by the initiator must be processed by the target in
CRN order if the CRN is non-zero.
There are certain scenarios where the Command Reference Number
sequence needs to be reset. When the target is power cycled, for
instance, the initiator needs to reset the CRN to 1. The initiator
will know this because it will see a LIP (when directly connected)
or get a logout/login event (when connected to a switch).
The isp(4) driver was not resetting the CRN when a target
went away and came back. When it saw the target again after a
power cycle, it would continue the CRN sequence where it left off.
The target would ignore the command because the CRN sequence is
supposed to be reset to 1 after a power cycle or other similar
event.
The symptom that the user would see is that there would be lots of
aborted INQUIRY commands after a tape library was power cycled, and
the library would fail to probe. The INQUIRY commands were being
ignored by the tape drive due to the CRN issue mentioned above.
isp_freebsd.c:
Add a new function, isp_fcp_reset_crn(). This will reset
all of the CRNs for a given port, or the CRNs for all LUNs
on a target.
Reset the CRNs for all targets on a port when we get a LIP,
loop reset, or loop down event.
Reset the CRN for a particular target when it arrives, is changed
or departs. This is less precise behavior than the
clearing behavior specified in the FCP-4 spec (which says
that it should be reset for PRLI, PRLO, PLOGI and LOGO),
but this is the level of information we have here. If this
is insufficient, then we will need to add more precise
notification from the lower level isp(4) code.
isp_freebsd.h:
Add a prototype for isp_fcp_reset_crn().
Sponsored by: Spectra Logic
MFC after: 1 week
In the current implementation, the isp_kthread() threads never exit.
The target threads do have an exit mode from isp_attach(), but it is
not invoked from isp_detach().
Ensure isp_detach() notifies threads started for each channel, such
that they exit before their parent device softc detaches, and thus
before the module does. Otherwise, a page fault panic occurs later in:
sysctl_kern_proc
sysctl_out_proc
kern_proc_out
fill_kinfo_proc
fill_kinfo_thread
strlcpy(kp->ki_wmesg, td->td_wmesg, sizeof(kp->ki_wmesg));
For isp_kthread() (and isp(4) target threads), td->td_wmesg references
now-unmapped memory after the module has been unloaded. These threads
are typically msleep()ing at the time of unload, but they could also
attempt to execute now-unmapped code segments.
MFC after: 1 month
Sponsored by: Spectra Logic
MFSpectraBSD: r1070921 on 2014/06/22 13:01:17
