reduce lock congestion and improve SMP scalability of the SCSI/ATA stack,
preparing the ground for the coming next GEOM direct dispatch support.
Replace big per-SIM locks with bunch of smaller ones:
- per-LUN locks to protect device and peripheral drivers state;
- per-target locks to protect list of LUNs on target;
- per-bus locks to protect reference counting;
- per-send queue locks to protect queue of CCBs to be sent;
- per-done queue locks to protect queue of completed CCBs;
- remaining per-SIM locks now protect only HBA driver internals.
While holding LUN lock it is allowed (while not recommended for performance
reasons) to take SIM lock. The opposite acquisition order is forbidden.
All the other locks are leaf locks, that can be taken anywhere, but should
not be cascaded. Many functions, such as: xpt_action(), xpt_done(),
xpt_async(), xpt_create_path(), etc. are no longer require (but allow) SIM
lock to be held.
To keep compatibility and solve cases where SIM lock can't be dropped, all
xpt_async() calls in addition to xpt_done() calls are queued to completion
threads for async processing in clean environment without SIM lock held.
Instead of single CAM SWI thread, used for commands completion processing
before, use multiple (depending on number of CPUs) threads. Load balanced
between them using "hash" of the device B:T:L address.
HBA drivers that can drop SIM lock during completion processing and have
sufficient number of completion threads to efficiently scale to multiple
CPUs can use new function xpt_done_direct() to avoid extra context switch.
Make ahci(4) driver to use this mechanism depending on hardware setup.
Sponsored by: iXsystems, Inc.
MFC after: 2 months
option left but actually consumed by ada(4), so move it to opt_ada.h
and get rid of opt_ata.h.
- Fix stand-alone build of atacore(4) by adding opt_cam.h.
- Use __FBSDID.
- Use DEVMETHOD_END.
- Use NULL instead of 0 for pointers.
- Move ata_timeout() to ata-all.c so we don't need to expose both this
function and ata_cam_end_transaction() but only the former.
- Move ata_cmd2str() from ata-queue.c to ata-all.c so we can get rid of
the former.
- Add some missing prototypes.
MFC after: 3 days
most kernels before FreeBSD 9.0. Remove such modules and respective kernel
options: atadisk, ataraid, atapicd, atapifd, atapist, atapicam. Remove the
atacontrol utility and some man pages. Remove useless now options ATA_CAM.
No objections: current@, stable@
MFC after: never
data, introduced by r246713. There are two places where ata_request is
filled in ATA_CAM: ata_cam_begin_transaction() and ata_cam_request_sense().
In the first case DMA should be done for addresses from the CCB. In second
case, DMA should be done to the different address, the address of the sense
buffer inside the CCB structure itself.
(interrupt). All other ATA PIO commands transfer one sector or 512 bytes
at one time. Hardcode these exceptions in ata(4) with ATA_CAM option.
This fixes timeout of READ LOG EXT command used by `smartctl -x /dev/adaX`.
Return PROTO_ATA protocol in response to XPT_PATH_INQ.
smartmontools uses it to identify ATA devices and I don't know any other
place now where it is important. It could probably use XPT_GDEV_TYPE
instead for more accurate protocol information, but let it live for now.
Reported by: matthew
MFC after: 3 days
until transport will do some probe actions (at least soft reset).
Make ATA/SATA SIMs to not report bogus and confusing PROTO_ATA protocol.
Make ATA/SATA transport to fill that gap by reporting protocol to SIM with
XPT_SET_TRAN_SETTINGS and patching XPT_GET_TRAN_SETTINGS results if needed.
to allow drivers to handle request completion directly without passing
them to the CAM SWI thread removing extra context switch.
Modify all ATA/SATA drivers to use them.
Reviewed by: gibbs, ken
MFC after: 2 weeks
along with functions, SYSCTLs and tunables that are not used with
ATA_CAM in #ifndef ATA_CAM, similar to the existing #ifdef'ed ATA_CAM
code for the other way around. This makes it easier to understand
which parts of ata(4) actually are used in the new world order and
to later on remove the !ATA_CAM bits. It also makes it obvious that
there is something fishy with the C-bus front-end as well as in the
ATP850 support, as these used ATA_LOCKING which is defunct in the
ATA_CAM case. When fixing the former, ATA_LOCKING probably needs to
be brought back in some form or other.
Reviewed by: mav
MFC after: 1 week
The SYSCTL_NODE macro defines a list that stores all child-elements of
that node. If there's no SYSCTL_DECL macro anywhere else, there's no
reason why it shouldn't be static.
option is defined. This sysctl can be queried by feature_present(3).
Query for this feature in /sbin/atacontrol and /usr/sbin/burncd.
If these utilities detect that ATA_CAM is enabled, then these utilities
will error out. These utilities are compatible with the old ATA
driver, but are incomptible with the new ATA_CAM driver. By erroring out,
we give end-users an idea as to what remedies to use, and reduce the need for them
to file PR's. For atacontrol, camcontrol must be used instead,
and for burncd, alternative utilties from the ports collection must be used
such as sysutils/cdrtools.
In future, maybe someone can re-write burncd to work with ATA_CAM,
but at least for now, we give a somewhat useful error message to end users.
PR: 160979
Reviewed by: jh, Arnaud Lacombe <lacombar at gmail dot com>
Reported by: Joe Barbish <fbsd8 at a1poweruser dot com>
MFC after: 3 days
- Implement proper combined mode decoding for Intel controllers to properly
identify SATA and PATA channels and associate ATA channels with SATA ports.
This fixes wrong reporting and in some cases hard resets to wrong SATA ports.
- Improve SATA registers support to handle hot-plug events and potentially
interface errors. For ICH5/6300ESB chipsets these registers accessible via
PCI config space. For later ones they may be accessible via PCI BAR(5).
- For controllers not generating interrupts on hot-plug events, implement
periodic status polling. Use it to detect hot-plug on Intel and VIA
controllers. Same probably could also be used for Serverworks and SIS.
Do not grab lock while setting up interrupt, as it causes LOR with
allocation code. Instead make interrupt handler check that CAM bus
initialization completed before touching it.
While there, slightly improve attach errors handling.
Reported by: kib
- 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.
Introduce ATA_CAM kernel option, turning ata(4) controller drivers into
cam(4) interface modules. When enabled, this options deprecates all ata(4)
peripheral drivers (ad, acd, ...) and interfaces and allows cam(4) drivers
(ada, cd, ...) and interfaces to be natively used instead.
As side effect of this, ata(4) mode setting code was completely rewritten
to make controller API more strict and permit above change. While doing
this, SATA revision was separated from PATA mode. It allows DMA-incapable
SATA devices to operate and makes hw.ata.atapi_dma tunable work again.
Also allow ata(4) controller drivers (except some specific or broken ones)
to handle larger data transfers. Previous constraint of 64K was artificial
and is not really required by PCI ATA BM specification or hardware.
Submitted by: nwitehorn (powerpc part)
long as I remember, and completely superseded by better maintained umass(4).
It's main idea was to optionally avoid CAM dependency for such devices, but
with move ATA to CAM, it is not actual any more.
No objections: hselasky@, thompsa@, arch@
- Remove most of direct relations between ATA(4) peripherial and controller
levels. It makes logic more transparent and is a mandatory step to wrap
ATA(4) controller level into ATA-native CAM SIM.
- Tune AHCI and SATA2 SiI drivers memory allocation a bit to allow bigger
I/O transaction sizes without additional cost.
The newbus lock is responsible for protecting newbus internIal structures,
device states and devclass flags. It is necessary to hold it when all
such datas are accessed. For the other operations, softc locking should
ensure enough protection to avoid races.
Newbus lock is automatically held when virtual operations on the device
and bus are invoked when loading the driver or when the suspend/resume
take place. For other 'spourious' operations trying to access/modify
the newbus topology, newbus lock needs to be automatically acquired and
dropped.
For the moment Giant is also acquired in some key point (modules subsystem)
in order to avoid problems before the 8.0 release as module handlers could
make assumptions about it. This Giant locking should go just after
the release happens.
Please keep in mind that the public interface can be expanded in order
to provide more support, if there are really necessities at some point
and also some bugs could arise as long as the patch needs a bit of
further testing.
Bump __FreeBSD_version in order to reflect the newbus lock introduction.
Reviewed by: ed, hps, jhb, imp, mav, scottl
No answer by: ariff, thompsa, yongari
Tested by: pho,
G. Trematerra <giovanni dot trematerra at gmail dot com>,
Brandon Gooch <jamesbrandongooch at gmail dot com>
Sponsored by: Yahoo! Incorporated
Approved by: re (ksmith)
requesting IDENTIFY from slave device first. This order is important
for proper cable type detection by master device.
PR: kern/136438
Approved by: re (kib)
