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)
compiled into the main AMR driver. It's code that is nice to have but not
required for normal operation, and it is reported to cause problems for some
people.
After I removed all the unit2minor()/minor2unit() calls from the kernel
yesterday, I realised calling minor() everywhere is quite confusing.
Character devices now only have the ability to store a unit number, not
a minor number. Remove the confusion by using dev2unit() everywhere.
This commit could also be considered as a bug fix. A lot of drivers call
minor(), while they should actually be calling dev2unit(). In -CURRENT
this isn't a problem, but it turns out we never had any problem reports
related to that issue in the past. I suspect not many people connect
more than 256 pieces of the same hardware.
Reviewed by: kib
- Improve error handling for load operations.
- Fix a memory corruption bug when using certain linux management apps.
- Allocate all commands up front to avoid OOM deadlocks later on.
T_DIRECT filtering so that disk drives can be attached via the
pass driver. Add CAM locking. Don't mark CAM commands as SG64
since the hardware isn't designed to deal with 64-bit passthru
commands. Hopefully the bounce buffer changes that were done
for the management/ioctl interface are robust enough to handle
this deficiency for CAM as well.
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
instead of doing the first load with the BUS_DMA_NOWAIT flag. On 4.x with
PAE and > 4gb of RAM this proved disastrous if there weren't enough bounce
pages as amr_mapcmd() would return failure but the callback would later
fire once enough bounce pages were available and would then overwrite
another command's S/G list.
MFC after: 3 days
Submitted by: scottl (4.x version)
Reviewed by: scottl (port from 4.x to HEAD)
from the amr_linux. This simplifies the amr_linux shim and puts the
smarts into amr.c.
I tested this with 2 amr controllers in one box. It seems to work
okay with them.
The real problem was that ioctl handlers needed to call amr_wait_command()
with the list lock held. This not only solves the completion race, it also
prevents bounce buffer corruption that could arise from amr_start() being
called without the proper locks held.
Discussed with: ps
MFC After: 3 days
the completion of the command can occur before tsleep is called and
the command ends up blocking forever since the wakeup has already
been called.
Submitted by: ups
routines.
- Add or replace cpu_spinwait() with DELAY(1) to a few of the busy
loops when reading from the controller to work around firmware bugs
which can crash the controller.
This is important with MegaLib, when issuing a GET_REBUILD_PROG since
it returns an error if the drive is not in rebuild state.
This will be MFC'ed shortly.
Submitted by: ps
Reviewed by: scottl
Found by: ambrisko
Linux LSI MegaRaid tools can run on FreeBSD until Linux emulation.
Add in the Linux IOCTL shim and create the megadev0 device so
Linux LSI MegaRaid tools can run on FreeBSD until Linux emulation.
Add glue to build the modules but don't tie it into the build
yet until I test it from the CVS repo. via the mirror on an
amd64 machine.
Tie this into the Linux32 emulation on amd64 so the tools can
run on amd64 kernel.
Cleaned up by: ps (amr_linux.c)
1. Implement a large set of ioctl shims so that the Linux management apps
from LSI will work. This includes infrastructure to support adding, deleting
and rescanning arrays at runtime. This is based on work from Doug Ambrosko,
heavily augmented by LSI and Yahoo.
2. Implement full 64-bit DMA support. Systems with more than 4GB of RAM
can now operate without the cost of bounce buffers. Cards that cannot do
64-bit DMA will automatically revert to using bounce buffers. This option
can be forced off by setting the 'hw.amr.force_sg32" tunable in the loader.
It should only be turned off for debugging purposes. This work was sponsored
by Yahoo.
3. Streamline the command delivery and interrupt handler paths after
much discussion with Dell and LSI. The logic now closely matches the
intended design, making it both more robust and much faster. Certain
i/o failures under heavy load should be fixed with this.
4. Optimize the locking. In the interrupt handler, the card can be checked
for completed commands without any locks held, due to the handler being
implicitely serialized and there being no need to look at any shared data.
Only grab the lock to return the command structure to the free pool. A
small optimization can still be made to collect all of the completions
together and then free them together under a single lock.
Items 3 and 4 significantly increase the performance of the driver. On an
LSI 320-2X card, transactions per second went from 13,000 to 31,000 in my
testing with these changes. However, these changes are still fairly
experimental and shouldn't be merged to 6.x until there is more testing.
Thanks to Doug Ambrosko, LSI, Dell, and Yahoo for contributing towards
this.
