It turns out Smart Array logical drives do not support target
reset and when the target reset fails, the logical drive will
be taken off line.  Symptoms look like this:

hpsa 0000:03:00.0: Abort request on C1:B0:T0:L0
hpsa 0000:03:00.0: resetting device 1:0:0:0
hpsa 0000:03:00.0: cp ffff880037c56000 is reported invalid (probably means target device no longer present)
hpsa 0000:03:00.0: resetting device failed.
sd 1:0:0:0: Device offlined - not ready after error recovery
sd 1:0:0:0: rejecting I/O to offline device
EXT3-fs error (device sdb1): read_block_bitmap:

LUN reset is supported though, and is what we should be using.
Target reset is also disruptive in shared SAS situations,
for example, an external MSA1210m which does support target
reset attached to Smart Arrays in multiple hosts -- a target
reset from one host is disruptive to other hosts as all LUNs
on the target will be reset and will abort all outstanding i/os
back to all the attached hosts.  So we should use LUN reset,
not target reset.

Tested this with Smart Array logical drives and with tape drives.
Not sure how this bug survived since 2009, except it must be very
rare for a Smart Array to require more than 30s to complete a request.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Dial back the aggressiveness of the controller lockup detection thread.
Currently it will declare the controller to be locked up if it goes
for 10 seconds with no interrupts and no change in the heartbeat
register.  Dial back this to 30 seconds with no heartbeat change, and
also snoop the ioctl path and if a firmware flash command is detected,
dial it back further to 4 minutes until the firmware flash command
completes.  The reason for this is that during the firmware flash
operation, the controller apparently doesn't update the heartbeat
register as frequently as it is supposed to, and we can get a false
positive.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NMike Miller <mikem@beardog.cce.hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Use spinlocks with finer granularity in the submission and
completion paths to allow concurrent execution for multiple
reply queues.  In particular, do not hold a spin lock while
submitting a request to the device, nor during most of the
interrupt handler.
Signed-off-by: NMatt Gates <matthew.gates@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Smart Arrays can support multiple reply queues onto which command
completions may be deposited.  It can help performance quite a bit
to arrange for command completions to be processed on the same CPU
from which they were submitted to increase the likelihood of cache
hits.
Signed-off-by: NMatt Gates <matthew.gates@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This is in order to smooth the way for upcoming changes to allow use of
multiple reply queues for command completions.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NMatt Gates <matthew.gates@hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

When aborting a command, the tag is supposed to be
specified as 64-bit little endian.  However, some smart
arrays expect the tag of the command to be aborted to be
specified in a strange byte order.  How to tell which sort
of Smart Array firmware we're dealing with is not obvious.
However, because of the way we construct our tags, the values
of any outstanding tag when specified with the "strange" byte
order will not collide with the value specified in the correct
order.  That means we can safely attempt the abort both ways.
Signed-off-by: NStephen M. Cameron <stephenmcameron@gmail.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Instead of giving up after 3 immediate retries of driver initiated
commands, back off the rate of retries and retry a bunch more times.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Reviewed-by: Andi Shyti <andi.shyti@gmail.com> 
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

In shared SAS configurations we might get a busy status
during driver initiated commands (e.g. during rescan for
devices).  We should retry the command in such cases rather
than giving up.
Signed-off-by: NMatt Bondurant <Matthew.dav.bondurant@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Default behavior for any CHECK CONDITION excepting a few special cases is to
print out certain parts of the sense buffer and the CDB.  Default behavior
should be to print nothing and let the upper layers or applications decide what
to do about these.  The same information is already available by setting the
appropriate bits of the scsi_logging_level kernel parameter or via
/proc/sys/dev/scsi/logging_level.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

pci_disable_device() disables the bus master bit and pci_enable_device does
not re-enable it.  It needs to be enabled.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

There was code to skip "disabled" devices which was intended to
skip devices disabled in the BIOS, but it really just checks to
see if the device can write to host memory, which this is disabled
by pci_disable_device on driver unload, so this check has the effect
of preventing subsequent load of the driver.  And devices disabled in
the BIOS don't show up at all anyway, so this check never made any
sense to begin with, and should be removed.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

As Jenx Axboe explained to me: "In earlier times (2.6.18 and pre, iirc), Linux
disabled IO and mem bars on pci_disable_device(). Now in newer kernel it does
not. And in the newer kernels you run into problems if you DON'T disable the
device on exit, since when it later loads the device is already in the enabled
state - and pci_enable_device() then does nothing. This typically screws
MSI/MSI-X." This is what the big scary comment that says pci_disable_device
does "something nasty" to smart arrays was evidently referring to.

If pci_disable_device is not called on driver rmmod, subsequently insmod'ing
the driver may in result in some cases fail to be able to receive interrupts,
esp.  if other drivers are loaded between unloading and loading hpsa.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Use check_signature to find a signature in the mmio address.
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Acked-by: NMike Miller <mike.miller@hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Some other older controllers also do have problems to perform a kdump.
Adding controllers to this list means that the driver will signal
this non-ability via a resettable flag correctly.
The unsupported list was created after a consultation with HP.
Signed-off-by: NTomas Henzl <thenzl@redhat.com>
Acked-by: NMike Miller <mike.miller@hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Use find_first_zero_bit to find the first cleared bit in a memory region.

This also includes the following minor changes.
- Use bitmap_zero
- Reduce unnecessary atomic bitops usage
Signed-off-by: NAkinobu Mita <akinobu.mita@gmail.com>
Acked-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Certain types of changes to devices should not be interpreted as a device
change that would cause the device to be removed and re-added.  These include
RAID level and Firmware revision changes.  However, these attribute changes DO
need to be reflected in the controller info structure's dev structure list, so
that sysfs and /proc info files for the devices will reflect the new values.
Signed-off-by: NScott Teel <scott.stacy.teel@hp.com>
Acked-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Reduce confusion and inaccuracy caused by dated naming of vars and functions
referring to external target devices.

CURRENT NAMING:                PROPOSED NAMING:

"MSA2xxx devices"              "external target devices"
msa2xxx_model                  ext_target_model
is_msa2xxx                     is_ext_target
add_msa2xxx_enclosure          add_ext_target_dev
nmsa2xxx_enclosures            n_ext_target_devs
Signed-off-by: NScott Teel <scott.teel@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Driver limits SAS external target IDs to range 1-8.
Need to increase limit and clean up overlapping concepts of targets and paths
in the code.

There are several defined constants that control this:
HPSA_MAX_TARGETS_PER_CTLR     16
MAX_MSA2XXX_ENCLOSURES        32
HPSA_MAX_PATHS                8

We can condense this to one constant:
MAX_EXT_TARGETS               32

SAS switches allow for 8 connections, and there is capacity for 4 switches per
enclosure in largest blade enclosure type.
Signed-off-by: NScott Teel <scott.teel@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

It should call hpsa_set_bus_target_lun rather
than individually setting bus, target and lun.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Some distros have a "rescan-scsi-bus.sh" script which depends on
SCSI REPORT LUNs not reporting something different than what the
driver tells the kernel, even if the driver uses scan_start and
scan_finished methods of the SCSI host template to override the
usual SCSI midlayer discovery code.  Previously, 1 was added to
the LUN to make room to insert the RAID controller device at
LUN 0.  Now, the RAID controller is moved to bus 3, and 1 is no
longer added to the LUN.  However, SCSI REPORT LUNS on Smart Array
doesn't report physical devices like tape drives or auto-loaders
as it turns out, so those particular device types still won't match.
Generally the logical drives are reported first however, so at
least those should match.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Upgraded firmware on Smart Array P7xx (and some others) made them show up as
SCSI revision 5 devices and this caused the driver to fail to map MSA2xxx
logical drives to the correct bus/target/lun.  A symptom of this would be that
the target ID of the logical drives as presented by the external storage array
is ignored, and all such logical drives are assigned to target zero,
differentiated only by LUN.  Some multipath software reportedly does not deal
well with this behavior, failing to recognize different paths to the same
device as such.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NScott Teel <scott.teel@hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Sometimes, for testing purposes (e.g. testing rmmod on a system
that normally boots using hpsa) it's nice to rename the driver
and split it into two drivers and restrict it to certain
controllers.  This makes that easier.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

hpsa_register_scsi just calls hpsa_scsi_detect.  Move
the guts of hpsa_scsi_detect into hpsa_register_scsi and
get rid of hpsa_scsi_detect.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

[SCSI] hpsa: removed unneeded structure member max_sg_entries and fix badly named constant MAXSGENTRIES

We had both h->max_sg_entries and h->maxsgentries in the per controller
structure which is terribly confusing.  max_sg_entries was really
just a constant, 32, which defines how big the "block fetch table"
is, which is as large as the max number of SG elements embedded
within a command (excluding SG elements in chain blocks).

MAXSGENTRIES was the constant used to denote the max number of SG
elements embedded within a command, also a poor name.

So renamed MAXSGENTREIS to SG_ENTRIES_IN_CMD, and removed
h->max_sg_entries and replaced it with SG_ENTRIES_IN_CMD.

h->maxsgentries is unchanged, and is the maximum number of sg
elements the controller will support in a command, including
those in chain blocks, minus 1 for the chain block pointer..
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Don't call kthread_stop with a spin lock held and interrupts
disabled because kthread_stop will sleep waiting for the thread
to stop.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The '5i' controller freezes when a kdump is attemted.
This patch admits it and adds the controller
to the unresetable list.
Signed-off-by: NTomas Henzl <thenzl@redhat.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

IRQF_SHARED is required for older controllers that don't support MSI(X)
and which may end up sharing an interrupt.  All the controllers hpsa
normally supports have MSI(X) capability, but older controllers may be
encountered via the hpsa_allow_any=1 module parameter.

Also remove deprecated IRQF_DISABLED.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The Windows driver .inf disables ASPM on hpsa devices. Do the same because the
selection of a non default ASPM policy can cause the device to hang.
Signed-off-by: NMatthew Garrett <mjg@redhat.com>
Cc: stable@kernel.org
Acked-by: NMike Miller <mike.miller@hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

When controller lockup condition is detected,
we should fail all outstanding commands and disable
the controller.  This will enable multipath solutions
to recover gracefully.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

We weren't filling in the transfer length of the
flush cache command (it transfers 4 bytes of zeroes).
Firmware didn't seem to be bothered by this, but it
should be fixed.
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The currentsd[] array in hpsa_update_scsi_devices had room for
256 devices.  The code was iterating over however many physical
and logical devices plus an additional number of possible external
MSA2XXX controllers, which together could potentially exceed 256.

We increased the size of the currentsd array to 1024 + 1024 + 32 + 1
elements to reflect a reasonable maximum possible number of devices
which might be encountered.  We also don't just walk off the end
of the array if the array controller reports more devices than we
are prepared to handle, we just ignore the excessive devices.
Signed-off-by: NScott Teel <scott.teel@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Rename HPSA_MAX_SCSI_DEVS_PER_HBA to HPSA_MAX_DEVICES
Signed-off-by: NScott Teel <scott.teel@hp.com>
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Set the max hardware sectors in the SCSI host template to 8192
to allow for larger i/o's (8192 is the same limit the cciss
driver currently has.)
Signed-off-by: NStephen M. Cameron <scameron@beardog.cce.hp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The P600 requires a small delay when changing states. Otherwise we may think
the board did not reset and we bail. This for kdump only and is particular
to the P600.
Signed-off-by: NMike Miller <mike.miller@hp.com>
Cc: stable@kernel.org
Signed-off-by: NJens Axboe <axboe@kernel.dk>