Commit Graph

8 Commits

Author SHA1 Message Date
Dan Williams
9095a64a9a [SCSI] libsas: fix timeout vs completion race
Until we have told the lldd to forget a task a timed out operation can
return from the hardware at any time.  Since completion frees the task
we need to make sure that no tasks run their normal completion handler
once eh has decided to manage the task.  Similar to
ata_scsi_cmd_error_handler() freeze completions to let eh judge the
outcome of the race.

Task collector mode is problematic because it presents a situation where
a task can be timed out and aborted before the lldd has even seen it.
For this case we need to guarantee that a task that an lldd has been
told to forget does not get queued after the lldd says "never seen it".
With sas_scsi_timed_out we achieve this with the ->task_queue_flush
mutex, rather than adding more time.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 14:06:08 -06:00
Dan Williams
87c8331fcf [SCSI] libsas: prevent domain rediscovery competing with ata error handling
libata error handling provides for a timeout for link recovery.  libsas
must not rescan for previously known devices in this interval otherwise
it may remove a device that is simply waiting for its link to recover.
Let libata-eh make the determination of when the link is stable and
prevent libsas (host workqueue) from taking action while this
determination is pending.

Using a mutex (ha->disco_mutex) to flush and disable revalidation while
eh is running requires any discovery action that may block on eh be
moved to its own context outside the lock.  Probing ATA devices
explicitly waits on ata-eh and the cache-flush-io issued during device
removal may also pend awaiting eh completion.  Essentially any rphy
add/remove activity needs to run outside the lock.

This adds two new cleanup states for sas_unregister_domain_devices()
'allocated-but-not-probed', and 'flagged-for-destruction'.  In the
'allocated-but-not-probed' state  dev->rphy points to a rphy that is
known to have not been through a sas_rphy_add() event.  At domain
teardown check if this device is still pending probe and cleanup
accordingly.  Similarly if a device has already been queued for removal
then sas_unregister_domain_devices has nothing to do.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:52:34 -06:00
Dan Williams
756f173fb5 [SCSI] libsas: fix leak of dev->sata_dev.identify_[packet_]device
These are never freed in the nominal path.  A domain_device has a
different lifetime than a sas_rphy we need a dev->rphy independent way
of identifying sata devices.

Reviewed-by: Jack Wang <jack_wang@usish.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2012-02-19 13:39:36 -06:00
James Bottomley
00dd4998a6 libsas: convert to libata new error handler
The conversion is quite complex given that the libata new error
handler has to be hooked into the current libsas timeout and error
handling.  The way this is done is to process all the failed commands
via libsas first, but if they have no underlying sas task (and they're
on a sata device) assume they are destined for the libata error
handler and send them accordingly.

Finally, activate the port recovery of the libata error handler for
each port known to the host.  This is somewhat suboptimal, since that
port may not need recovering, but given the current architecture of
the libata error handler, it's the only way; and the spurious
activation is harmless.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
2011-03-02 02:36:45 -05:00
James Bottomley
79bc14813c [SCSI] libsas: fix missing inlines in header file
Two functions in include/scsi/sas_ata.h don't have static inlines
leading to problems if they're built in:

On Thu, 2008-04-03 at 14:06 +0200, Toralf Förster wrote:
> drivers/scsi/mvsas.o: In function `sas_ata_init_host_and_port':
> mvsas.c:(.text+0x0): multiple definition of `sas_ata_init_host_and_port'
> drivers/scsi/libsas/built-in.o:(.text+0x37f4): first defined here
> drivers/scsi/mvsas.o: In function `sas_ata_task_abort':
> mvsas.c:(.text+0x7): multiple definition of `sas_ata_task_abort'
> drivers/scsi/libsas/built-in.o:(.text+0x37fb): first defined here
> make[2]: *** [drivers/scsi/built-in.o] Error 1
> make[1]: *** [drivers/scsi] Error 2
> make: *** [drivers] Error 2

Add the correct static inline modifiers.

Tested-by: Toralf Förster <toralf.foerster@gmx.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
2008-04-07 12:19:10 -05:00
James Bottomley
b91421749a [SCSI] libsas: make ATA functions selectable by a config option
Not everyone wants libsas automatically to pull in libata.  This patch
makes the behaviour configurable, so you can build libsas with or
without ATA support.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-07-22 13:23:13 -05:00
Darrick J. Wong
3a2755af37 [SCSI] sas_ata: Implement sas_task_abort for ATA devices
ATA devices need special handling for sas_task_abort.  If the ATA command
came from SCSI, then we merely need to tell SCSI to abort the scsi_cmnd.
However, internal commands require a bit more work--we need to fill the qc
with the appropriate error status and complete the command, and eventually
post_internal will issue the actual ABORT TASK.

Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-07-18 11:16:03 -05:00
Darrick J. Wong
338ec57003 [SCSI] Migrate libsas ATA code into a separate file
This is a respin of my earlier patch that migrates the ATA support code
into a separate file.  For now, the controversial linking bits have
been removed per James Bottomley's request for a patch that contains
only the migration diffs, which means that libsas continues to require
libata.  I intend to address that problem in a separate patch.

This patch is against the aic94xx-sas-2.6 git tree, and it has been
sanity tested on my x206m with Seagate SATA and SAS disks without
uncovering any new problems.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
2007-07-18 11:14:40 -05:00