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
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.
- Introduce the amr_io_lock to control access to command queues, bio queues,
and the hardware.
- Eliminate the taskqueue and do all completion processing in the ithread.
- Assign a static slot number to each command instead of doing a linear
search for free slots each time a command is needed.
- Modify the interrupt handler to more closely match what Linux does, for
safety.
properly support bounce buffers and resource shortages. This allows the
driver to work properly and reliably with more than 4GB of RAM. Of the
three data paths that exist in the driver, (block, CAM, ioctl), the ioctl
path has not been well tested with these changes due to difficulty with
finding an application that uses it that actually works.
Sponsored by: The FreeBSD Foundation and FreeBSD Systems, Inc.
Add two new arguments to bus_dma_tag_create(): lockfunc and lockfuncarg.
Lockfunc allows a driver to provide a function for managing its locking
semantics while using busdma. At the moment, this is used for the
asynchronous busdma_swi and callback mechanism. Two lockfunc implementations
are provided: busdma_lock_mutex() performs standard mutex operations on the
mutex that is specified from lockfuncarg. dftl_lock() is a panic
implementation and is defaulted to when NULL, NULL are passed to
bus_dma_tag_create(). The only time that NULL, NULL should ever be used is
when the driver ensures that bus_dmamap_load() will not be deferred.
Drivers that do not provide their own locking can pass
busdma_lock_mutex,&Giant args in order to preserve the former behaviour.
sparc64 and powerpc do not provide real busdma_swi functions, so this is
largely a noop on those platforms. The busdma_swi on is64 is not properly
locked yet, so warnings will be emitted on this platform when busdma
callback deferrals happen.
If anyone gets panics or warnings from dflt_lock() being called, please
let me know right away.
Reviewed by: tmm, gibbs
Retain the mistake of not updating the devstat API for now.
Spell bioq_disksort() consistently with the remaining bioq_*().
#include <geom/geom_disk.h> where this is more appropriate.
in geom_disk.c.
As a side effect this makes a lot of #include <sys/devicestat.h>
lines not needed and some biofinish() calls can be reduced to
biodone() again.
as module. This also fix's issue kern/45713.
Fix - polling was implemented incorrectly for
adapter enquiry and adapter flush.
(2) Problem: PANIC when unloading driver
as module.
Fix - device nodes are not destroyed for amr0,
and amrd* when driver is unloaded
(3) Problem: PANIC from loading driver when
3ware adapter present, error message "Warning
"amrd is usurping twed's bmaj"
Fix - put #idef freebsd version < 500000 for
bmaj -1 -> amrd_cdevsw
(4) Problem: warnings in driver when compiling
with DAMR_DEBUG param enabled in Makefile
Fix - fix the warnings so driver can compile
when -Werror is present in Makefile.
Approved by: jhb
MFC: 7 days
amr_cam.c,
amrreg.h,
amrvar.h:
- added support for 12/16 byte cdb's, effecting CAM branch only ( non-disk support )
amrreg.h:
- increased number of scatter gather elements from 16 to 26.
amr_pci.c:
- amr_pci_free(), incorrect bus tag meant for 'amr_mailbox_dmat' was being freed
all:
- copyright change requested by scottl
Reviewed by: ps,scottl
MFC after: 1 week
changes for "LSILogic"
(2) enabled non-disk support through CAM interface
(3) HA_INQ (a) enabled tagged queuing (b) disable reset during
driver loading (b) renamed BSDi string to LSI
(4) disabled detecting disk devices during SCSI INQUIRY
(5) changed dcdb single element sglist to send one entire buffer chunk
(6) nsgelem not set in sglist
(7) ap_data_transfer_length not set for dcdb
(8) changed "struct thread" to "d_thread_t" for compatibliity { xxx_open,
xxx_close, xxx_ioctl }
(9) miscellaneous compatiblity fixes
(10) bug fix for 0x0409/0x1000 card
(11) added compiling amr_cam.c in sys/conf/files
(12) added compiling amr_cam.c in sys/modules/amr/Makefile
Reviewed by:ps
MFC after:1 week
1 week
- New support for 40LD firmware found in Series 475 and 471 adapters.
- Better support for 8LD firmware adapters
- Ioctl passthrough interface for userland utilities.
- Improved error handling and queueing.
- Several bugfixes (including the 'still open' shutdown bug and
closing some small race conditions).
- Zone-style command allocator, reducing memory wasted under heavy
load conditions.
- CAM interface (disabled and not fully working) for SCSI passthrough
access to non-disk devices
Thanks to AMI for supplying a pile of new adapters and various other
help in making this happen.
<sys/bio.h>.
<sys/bio.h> is now a prerequisite for <sys/buf.h> but it shall
not be made a nested include according to bdes teachings on the
subject of nested includes.
Diskdrivers and similar stuff below specfs::strategy() should no
longer need to include <sys/buf.> unless they need caching of data.
Still a few bogus uses of struct buf to track down.
Repocopy by: peter
- Add periodic status monitoring routine. Currently just detects
lost commands, further functionality pending data from AMI.
Add some new commands states; WEDGED (never coming back) and
LATE (for when a command that wasmarked as WEDGED comes bacj,
- Remove a number of redundant efforts to poll the card for completed
commands. This is what interrupt handlers are for.
- Limit the maximum number of outstanding I/O transactions. It seems
that some controllers report more than they can really handle,
and exceding this limit can cause the controller to lock up.
- Don't use 'wait' mode for anything where the controller might not
be able to generate interrupts. (Keep the 'wait' mode though sa it
will become useful when we start taking userspace commands.
- Use a similar atomic locking trategy to the Mylex driver to prevent
some reentrancy problems.
- Correctly calculate the block count for non-whoile-bloch transfers
(actually illegal).
- Use the dsik device's si_drv1 field instead of b_driver1 in the
buf struct to pass the driver identifier arond.
- Rewrite amr_start and amr_done() along the lines of the Mylex driver
in order to improve robustnes.
- Always force the PCI busmaster bit on.
the AMI PCI controllers using the 8LD firmware interface (40LD firmware
will be supported as soon as I have hardware to test with).
These controllers are rebadged by Dell as the PERC, as well as by HP
and possibly other vendors.
