linux-toradex.git/drivers/scsi/ipr.c, branch v3.4.45

[SCSI] libsas, libata: fix start of life for a sas ata_port

2012-04-23T11:11:47+00:00

This changes the ordering of initialization and probing events from:
  1/ allocate rphy in PORTE_BYTES_DMAED, DISCE_REVALIDATE_DOMAIN
  2/ allocate ata_port and schedule port probe in DISCE_PROBE
...to:
  1/ allocate ata_port in PORTE_BYTES_DMAED, DISCE_REVALIDATE_DOMAIN
  2/ allocate rphy in PORTE_BYTES_DMAED, DISCE_REVALIDATE_DOMAIN
  3/ schedule port probe in DISCE_PROBE

This ordering prevents PHYE_SIGNAL_LOSS_EVENTS from sneaking in to
destrory ata devices before they have been fully initialized:

  BUG: unable to handle kernel paging request at 0000000000003b10
  IP: [] sas_ata_end_eh+0x12/0x5e [libsas]
  ...
  [] sas_unregister_common_dev+0x78/0xc9 [libsas]
  [] sas_unregister_dev+0x4f/0xad [libsas]
  [] sas_unregister_domain_devices+0x7f/0xbf [libsas]
  [] sas_deform_port+0x61/0x1b8 [libsas]
  [] sas_phye_loss_of_signal+0x29/0x2b [libsas]

...and kills the awkward "sata domain_device briefly existing in the
domain without an ata_port" state.

Reported-by: Michal Kosciowski 
Signed-off-by: Dan Williams 
Acked-by: Jeff Garzik 
Signed-off-by: James Bottomley

[SCSI] ipr: Increase alignment boundary of command blocks

2012-03-28T14:06:50+00:00

The latest generation of ipr hardware performs best when command blocks
are aligned to a boundary equal to the size of the command block. Ensure
512 byte alignment, since this is the largest size command block we
can send.

Signed-off-by: Brian King 
Signed-off-by: James Bottomley

[SCSI] ipr: Increase max concurrent oustanding commands

2012-03-28T14:04:47+00:00

Increase the total number of max concurrent outstanding commands
for the most recent family of adapters in order to improve overall
adapter performance.

Signed-off-by: Brian King 
Signed-off-by: James Bottomley

[SCSI] ipr: Remove unnecessary memory barriers

2012-03-28T14:02:48+00:00

The ipr driver added some memory barriers in order to ensure
a PowerPC sync instruction was executed prior to sending a
command to the adapter to ensure the command block was
coherent with respect to the PCI bus's view of memory.
However, some time ago, the powerpc architecture writel
macros were changed to include the sync since most drivers
don't properly handle this. So remove these memory barriers
since they are not needed and result in executing twice
as many sync instructions, which has a significant performance
penalty.

Signed-off-by: Brian King 
Signed-off-by: James Bottomley

[SCSI] ipr: Remove unnecessary interrupt clearing on new adapters

2012-03-28T14:01:06+00:00

The latest ipr hardware no longer requires the driver to issue any MMIOs
to clear the interrupt so remove this to optimize performance.

Signed-off-by: Brian King 
Signed-off-by: James Bottomley

[SCSI] ipr: Fix target id allocation re-use problem

2012-03-28T13:58:11+00:00

For the latest ipr SAS adapters, target id's are a completely
logical construct that are managed in the ipr driver. This fixes
an issue that can arise if a device is deleted via sysfs. If
a new device is then physically added, it will use the previous
device's target id. If the host is then rescanned, the device
that had been deleted, since it is using the same target id as
the new device is using, will never be found, resulting in
a missing device. Fix this by only freeing the target id
only if the resource is actually gone.

Signed-off-by: Brian King 
Signed-off-by: James Bottomley

[SCSI] ipr: update PCI ID definitions for new adapters

2012-02-29T22:48:27+00:00

This patch updates some PCI ID definitions for new adapters based on the next
generation 64 bit IOA PCI interface chip.

Signed-off-by: Wayne Boyer 
Acked-by: Brian King 
Signed-off-by: James Bottomley

[SCSI] ipr: fix eeh recovery for 64-bit adapters

2012-02-18T14:33:13+00:00

In some scenarios, an EEH error can take a long time to be detected, since the
driver issues an MMIO read only after a device reset command times out and we
try to reset the adapter. This patch adds some code in ipr_cancel_op() to read
a hardware register so we detect the error earlier in case the op is being
aborted because of a timeout caused by a frozen adapter slot.

Another problem in such scenarios is that in __ipr_eh_host_reset() we change the
dump state flag from WAIT_FOR_DUMP to GET_DUMP, and the flag is later changed
from GET_DUMP to READ_DUMP in ipr_reset_restore_cfg_space(). However, if when
__ipr_eh_host_reset() is called by the SCSI error handling the function
ipr_reset_restore_cfg_space() has already been called by the PCI EEH code, we
end up with the flag in an inconsistent state. This patch also prevents this
problem.

Signed-off-by: Kleber Sacilotto de Souza 
Acked-by: Brian King 
Signed-off-by: James Bottomley

PCI: Rework config space blocking services

2012-01-06T20:10:33+00:00

pci_block_user_cfg_access was designed for the use case that a single
context, the IPR driver, temporarily delays user space accesses to the
config space via sysfs. This assumption became invalid by the time
pci_dev_reset was added as locking instance. Today, if you run two loops
in parallel that reset the same device via sysfs, you end up with a
kernel BUG as pci_block_user_cfg_access detect the broken assumption.

This reworks the pci_block_user_cfg_access to a sleeping service
pci_cfg_access_lock and an atomic-compatible variant called
pci_cfg_access_trylock. The former not only blocks user space access as
before but also waits if access was already locked. The latter service
just returns false in this case, allowing the caller to resolve the
conflict instead of raising a BUG.

Adaptions of the ipr driver were originally written by Brian King.

Acked-by: Brian King 
Acked-by: Michael S. Tsirkin 
Signed-off-by: Jan Kiszka 
Signed-off-by: Jesse Barnes

[SCSI] ipr: add definitions for additional adapter

2011-10-31T09:12:50+00:00

Add the appropriate definition and table entry for an additional adapter.

Signed-off-by: Wayne Boyer 
Acked-by: Brian King 
Signed-off-by: James Bottomley