- change the way in which command queue overflow is handled;
- do not expose to CAM two command slots, used for driver's internal purposes;
- allow driver to use up to 1024 command slots, instead of 256 before.
- Unify bus reset/probe sequence. Whenever bus attached at boot or later,
CAM will automatically reset and scan it. It allows to remove duplicate
code from many drivers.
- Any bus, attached before CAM completed it's boot-time initialization,
will equally join to the process, delaying boot if needed.
- New kern.cam.boot_delay loader tunable should help controllers that
are still unable to register their buses in time (such as slow USB/
PCCard/ CardBus devices), by adding one more event to wait on boot.
- To allow synchronization between different CAM levels, concept of
requests priorities was extended. Priorities now split between several
"run levels". Device can be freezed at specified level, allowing higher
priority requests to pass. For example, no payload requests allowed,
until PMP driver enable port. ATA XPT negotiate transfer parameters,
periph driver configure caching and so on.
- Frozen requests are no more counted by request allocation scheduler.
It fixes deadlocks, when frozen low priority payload requests occupying
slots, required by higher levels to manage theit execution.
- Two last changes were holding proper ATA reinitialization and error
recovery implementation. Now it is done: SATA controllers and Port
Multipliers now implement automatic hot-plug and should correctly
recover from timeouts and bus resets.
- Improve SCSI error recovery for devices on buses without automatic sense
reporting, such as ATAPI or USB. For example, it allows CAM to wait, while
CD drive loads disk, instead of immediately return error status.
- Decapitalize diagnostic messages and make them more readable and sensible.
- Teach PMP driver to limit maximum speed on fan-out ports.
- Make boot wait for PMP scan completes, and make rescan more reliable.
- Fix pass driver, to return CCB to user level in case of error.
- Increase number of retries in cd driver, as device may return several UAs.
- Implement MSI support (MSIX support was already there)
- Use a table to drive MSI/MSIX exceptions
- Pre-calculate the command address instead of wasting cycles doing the
calculation on every i/o.
number of MSIX interrupts that are needed, and don't strictly check for 4.
Enable enough interrupt mask bits so that the controller will generate
interrupts in PERFORMANT mode. This fixes the hang-on-boot issues that
people were seeing with newer controllers.
modularize it so that new transports can be created.
Add a transport for SATA
Add a periph+protocol layer for ATA
Add a driver for AHCI-compliant hardware.
Add a maxio field to CAM so that drivers can advertise their max
I/O capability. Modify various drivers so that they are insulated
from the value of MAXPHYS.
The new ATA/SATA code supports AHCI-compliant hardware, and will override
the classic ATA driver if it is loaded as a module at boot time or compiled
into the kernel. The stack now support NCQ (tagged queueing) for increased
performance on modern SATA drives. It also supports port multipliers.
ATA drives are accessed via 'ada' device nodes. ATAPI drives are
accessed via 'cd' device nodes. They can all be enumerated and manipulated
via camcontrol, just like SCSI drives. SCSI commands are not translated to
their ATA equivalents; ATA native commands are used throughout the entire
stack, including camcontrol. See the camcontrol manpage for further
details. Testing this code may require that you update your fstab, and
possibly modify your BIOS to enable AHCI functionality, if available.
This code is very experimental at the moment. The userland ABI/API has
changed, so applications will need to be recompiled. It may change
further in the near future. The 'ada' device name may also change as
more infrastructure is completed in this project. The goal is to
eventually put all CAM busses and devices until newbus, allowing for
interesting topology and management options.
Few functional changes will be seen with existing SCSI/SAS/FC drivers,
though the userland ABI has still changed. In the future, transports
specific modules for SAS and FC may appear in order to better support
the topologies and capabilities of these technologies.
The modularization of CAM and the addition of the ATA/SATA modules is
meant to break CAM out of the mold of being specific to SCSI, letting it
grow to be a framework for arbitrary transports and protocols. It also
allows drivers to be written to support discrete hardware without
jeopardizing the stability of non-related hardware. While only an AHCI
driver is provided now, a Silicon Image driver is also in the works.
Drivers for ICH1-4, ICH5-6, PIIX, classic IDE, and any other hardware
is possible and encouraged. Help with new transports is also encouraged.
Submitted by: scottl, mav
Approved by: re
that there are 3 different interrupt enable bits, 2 for different
families of cards, and 1 for when MSI is used. Also apply a big
hammer backstop for cards that aren't recognized. This should fix
all of the interrupt issues at boot.
code interfered with Performant mode and legacy interrupts. Also
remove a register read operation on the Simplq code that was
effectively a time-wasting no-op.
1. The FreeBSD driver was setting an interrupt coalesce delay of 1000us
for reasons that I can only speculate on. This was hurting everything
from lame sequential I/O "benchmarks" to legitimate filesystem metadata
operations that relied on serialized barrier writes. One of my
filesystem tests went from 35s to complete down to 6s.
2. Implemented the Performant transport method. Without the fix in
(1), I saw almost no difference. With it, my filesystem tests showed
another 5-10% improvement in speed. It was hard to measure CPU
utilization in any meaningful way, so it's not clear if there was a
benefit there, though there should have been since the interrupt handler
was reduced from 2 or more PCI reads down to 1.
3. Implemented MSI-X. Without any docs on this, I was just taking a
guess, and it appears to only work with the Performant method. This
could be a programming or understanding mistake on my part. While this
by itself made almost no difference to performance since the Performant
method already eliminated most of the synchronous reads over the PCI
bus, it did allow the CISS hardware to stop sharing its interrupt with
the USB hardware, which in turn allowed the driver to become decoupled
from the Giant-locked USB driver stack. This increased performance by
almost 20%. The MSI-X setup was done with 4 vectors allocated, but only
1 vector used since the performant method was told to only use 1 of 4
queues. Fiddling with this might make it work with the simpleq method,
not sure. I did not implement MSI since I have no MSI-specific hardware
in my test lab.
4. Improved the locking in the driver, trimmed some data structures.
This didn't improve test times in any measurable way, but it does look
like it gave a minor improvement to CPU usage when many
processes/threads were doing I/O in parallel. Again, this was hard to
accurately test.
NOP-message polling in ciss_periodic().
Note that setting the tunable to non-zero can be workaround only for
`ADAPTER HEARTBEAT FAILED' problem, and may freeze the system w/o
the problem.
Reviewed by: scottl
Reported by: Attila Nagy
MFC after: 3 days
to kproc_xxx as they actually make whole processes.
Thos makes way for us to add REAL kthread_create() and friends
that actually make theads. it turns out that most of these
calls actually end up being moved back to the thread version
when it's added. but we need to make this cosmetic change first.
I'd LOVE to do this rename in 7.0 so that we can eventually MFC the
new kthread_xxx() calls.
now takes a device_t to be the parent of the bus that is being created.
Most SIMs have been updated with a reasonable argument, but a few exceptions
just pass NULL for now. This argument isn't used yet and the newbus
integration likely won't be ready until after 7.0-RELEASE.
use to synchornize and protect all data objects that are used for that
SIM. Drivers that are not yet MPSAFE register Giant and operate as
usual. RIght now, no drivers are MPSAFE, though a few will be changed
in the coming week as this work settles down.
The driver API has changed, so all CAM drivers will need to be recompiled.
The userland API has not changed, so tools like camcontrol do not need to
be recompiled.
the CAM_NEW_TRAN_CODE that has been in the tree for some years now.
This first step consists solely of adding to or correcting
CAM_NEW_TRAN_CODE pieces in the kernel source tree such
that a both a GENERIC (at least on i386) and a LINT build
with CAM_NEW_TRAN_CODE as an option will compile correctly
and run (at least with some the h/w I have).
After a short settle time, the other pieces (making
CAM_NEW_TRAN_CODE the default and updating libcam
and camcontrol) will be brought in.
This will be an incompatible change in that the size of structures
related to XPT_PATH_INQ and XPT_{GET,SET}_TRAN_SETTINGS change
in both size and content. However, basic system operation and
basic system utilities work well enough with this change.
Reviewed by: freebsd-scsi and specific stakeholders
command. This fixes some weird booting issues on newer versions
of the firmware on the MSA20.
Reported by: Philippe Pegon <Philippe dot Pegon at crc dot u-strasbg dot fr>
