Commit graph

291 commits

Author SHA1 Message Date
Dan Williams
ac013ed1cb [SCSI] isci: export phy events via ->lldd_control_phy()
Allow the sas-transport-class to update events for local phys via a new
PHY_FUNC_GET_EVENTS command to ->lldd_control_phy().  Fixup drivers that
are not prepared for new enum phy_func values, and unify
->lldd_control_phy() error codes.

These are the SAS defined phy events that are reported in a
smp-report-phy-error-log command:
 * /sys/class/sas_phy/<phyX>/invalid_dword_count
 * /sys/class/sas_phy/<phyX>/running_disparity_error_count
 * /sys/class/sas_phy/<phyX>/loss_of_dword_sync_count
 * /sys/class/sas_phy/<phyX>/phy_reset_problem_count

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:24:26 -05:00
Jeff Skirvin
cdd05f05b4 [SCSI] isci: The port state should be set to stopping on the last phy.
Fixes a bug where any phy removed from the port set the port
state to "stopping" - do this only when the last phy removed
from the port.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:22:28 -05:00
Jeff Skirvin
7582ba8bdf [SCSI] isci: fix decode of DONE_CRC_ERR TC completion status
DONE_CRC_ERR is not a RNC suspension condition, so do not change the
state to expect the incoming suspension notification.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
[djbw: dropped DONE_CMD_LL_R_ERR change]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:21:51 -05:00
Jeff Skirvin
cd06b9bae1 [SCSI] isci: SATA/STP I/O is only returned in the normal path to libsas
Since libsas has it's own means to escalate SATA/STP device error
handling depending on task status codes, return all SATA/STP I/O
on the normal path.

i.e. skip sas_task_abort() and let sas_ata_task_done() disposition the
qc.  Longer term we want to audit non-essential calls to
sas_task_abort().

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:21:24 -05:00
Dan Williams
b50102d3e9 [SCSI] isci: atapi support
Based on original implementation from Jiangbi Liu and Maciej Trela.

ATAPI transfers happen in two-to-three stages.  The two stage atapi
commands are those that include a dma data transfer.  The data transfer
portion of these operations is handled by the hardware packet-dma
acceleration.  The three-stage commands do not have a data transfer and
are handled without hardware assistance in raw frame mode.

stage1: transmit host-to-device fis to notify the device of an incoming
atapi cdb.  Upon reception of the pio-setup-fis repost the task_context
to perform the dma transfer of the cdb+data (go to stage3), or repost
the task_context to transmit the cdb as a raw frame (go to stage 2).

stage2: wait for hardware notification of the cdb transmission and then
go to stage 3.

stage3: wait for the arrival of the terminating device-to-host fis and
terminate the command.

To keep the implementation simple we only support ATAPI packet-dma
protocol (for commands with data) to avoid needing to handle the data
transfer manually (like we do for SATA-PIO).  This may affect
compatibility for a small number of devices (see
ATA_HORKAGE_ATAPI_MOD16_DMA).

If the data-transfer underruns, or encounters an error the
device-to-host fis is expected to arrive in the unsolicited frame queue
to pass to libata for disposition.  However, in the DONE_UNEXP_FIS (data
underrun) case it appears we need to craft a response.  In the
DONE_REG_ERR case we do receive the UF and propagate it to libsas.

Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:20:03 -05:00
Jeff Skirvin
983d3fdd33 [SCSI] isci: fix missed unlock in apc_agent_timeout()
Needed to jump to scic_lock unlock.

Also spotted by coccicheck.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:08:00 -05:00
Dan Williams
54b5e3a4bf [SCSI] isci: fix support for large smp requests
Kill the local smp response buffer.

Besides being unnecessary, it is too small (currently truncates
responses to 60 bytes).  The mid-layer will have already allocated a
sufficiently sized buffer, just kmap and copy into it directly.

Cc: <stable@kernel.org>
Reported-by: Derick Marks <derick.w.marks@intel.com>
Tested-by: Derick Marks <derick.w.marks@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-10-02 13:07:17 -05:00
Dan Williams
ad4f4c1de8 [SCSI] isci: initial sgpio write support
Basic support to initialize the gpio unit, accept an incomming
SAS_GPIO_REG_TX_GP bitstream, and translate it to the ODx.n fields in
the hardware registers.  If register indexes outside the supported range
are specified in the SMP frame we simply accept the write and return how
many registers (SFF-8485) were written (libsas reports this as residue
in the request).

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-09-22 15:01:56 +04:00
Dan Williams
13257cfbc5 [SCSI] isci: fix sgpio register definitions
output_data_select registers are off by one u32

delete the macros we will never use.

Reported-by: Artur Wojcik <artur.wojcik@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-09-22 15:00:56 +04:00
Dan Williams
4fcf812ca3 [SCSI] libsas: export sas_alloc_task()
Now that isci has added a 3rd open coded user of this functionality just
share the libsas version.

Acked-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>
2011-08-27 08:35:13 -06:00
Dan Williams
98e2a5a3a1 [SCSI] isci: add version number
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-23 20:06:14 -07:00
Dan Williams
77cd72a53f [SCSI] isci: fix event-get pointer increment
Hardware only increments the put pointer on event types >= 4.  Do not
increment the get pointer for event type 3.

Reported-by: Kapil Karkra <kapil.karkra@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-23 20:05:47 -07:00
Dan Williams
9b4be52899 [SCSI] isci: dynamic interrupt coalescing
Hardware allows both an outstanding number commands and a timeout value
(whichever occurs first) as a gate to the next interrupt generation.  This
scheme at completion time looks at the remaining number of outstanding tasks
and sets the timeout to maximize small transaction operation.  If transactions
are large (take more than a few 10s of microseconds to complete) then
performance is not interrupt processing bound, so the small timeouts this
scheme generates are overridden by the time it takes for a completion to
arrive.

Tested-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-23 20:04:42 -07:00
Jeff Skirvin
39ea2c5b5f [SCSI] isci: Leave requests alone if already terminating.
Instead of immediately completing any request that has a second
termination call made on it, wait for the TC done/abort HW event.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-23 19:58:44 -07:00
Dave Jiang
3a7bda830f [SCSI] isci: Adding documentation to API change and fixup sysfs registration
Adding API update for adding isci_id entry scsi_host sysfs entry.
Also fixing up the sysfs registration to the scsi_host template

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-23 19:54:24 -07:00
Marcin Tomczak
985af6f70d [SCSI] isci: change sas phy timeouts from 54us to 59us
Need the following workaround in the driver for interoperability with
the older Intel SSD drives and any other SATA drive that may exhibit the
same behavior. This is a corner case where SCU speed is limited to
either 3G or 1.5G and the drive has a period of DC idle when it switches
speed during SATA speed negotiation. Workaround :change PHYTOV[31:24]
from 0x36 to 0x3B.

Signed-off-by: Marcin Tomczak <marcin.tomczak@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-23 19:52:14 -07:00
Dan Williams
ee33e2b771 [SCSI] isci: fix 32-bit operation when CONFIG_HIGHMEM64G=n
The unsolicited frame control infrastructure requires a table of dma
addresses for the hardware to lookup the frame buffer location by an
index.  The hardware expects the elements of this table to be 64-bit
quantities, so we cannot reference these elements as dma_addr_t.  All
unsolicited frame protocols are affected, particularly SATA-PIO and SMP
which prevented direct-attached SATA drives and expander-attached drives
to not be discovered.

Cc: <stable@kernel.org>
Reported-by: Jacek Danecki <jacek.danecki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-23 19:50:27 -07:00
Dan Williams
1a87828447 [SCSI] isci: fix sata response handling
A bug (likely copy/paste) that has been carried from the original
implementation.  The unsolicited frame handling structure returns the
d2h fis in the isci_request.stp.rsp buffer.

Cc: <stable@kernel.org>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-08-23 19:45:45 -07:00
James Bottomley
a5ec7f86dc [SCSI] isci: fix checkpatch errors
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
2011-07-03 14:26:24 -05:00
Jeff Skirvin
bc6f387d31 isci: Device reset should request sas_phy_reset(phy, true)
The hard_reset parameter passed to the LLDD in the direct-attached
phy control case allows the LLDD to filter link failure events
while the direct-attached device reset is executing.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
a8a0a133b0 isci: pare back error messsages
The messages emitted from task.c and some from request.c likely
duplicate (in a less undertandable way) what is reported by the
midlayer.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
dc00c8b694 isci: cleanup silicon revision detection
Perform checking per-pci device (even though all systems will only have
1 pci device in this generation), and delete support for silicon that
does not report a proper revision (i.e. A0).

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
4e4dca3de9 isci: merge scu_unsolicited_frame.h into unsolicited_frame_control.h
Does not need its own file.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
16ba77091b isci: merge sata.[ch] into request.c
Undo some needless separation.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
34a991587a isci: kill 'get/set' macros
Most of these simple dereference macros are longer than their open coded
equivalent.  Deleting enum sci_controller_mode is thrown in for good
measure.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
89a7301f21 isci: retire scic_sds_ and scic_ prefixes
The distinction between scic_sds_ scic_ and sci_ are no longer relevant
so just unify the prefixes on sci_.  The distinction between isci_ and
sci_ is historically significant, and useful for comparing the old
'core' to the current Linux driver. 'sci_' represents the former core as
well as the routines that are closer to the hardware and protocol than
their 'isci_' brethren. sci == sas controller interface.

Also unwind the 'sds1' out of the parameter structs.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
d9dcb4ba79 isci: unify isci_host and scic_sds_controller
Remove the distinction between these two implementations and unify on
isci_host (local instances named ihost).  Hmmm, we had two
'oem_parameters' instances, one was unused... nice.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
78a6f06e0e isci: unify isci_remote_device and scic_sds_remote_device
Remove the distinction between these two implementations and unify on
isci_remote_device (local instances named idev).

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
ffe191c92f isci: unify isci_port and scic_sds_port
Remove the distinction between these two implementations and unify on
isci_port (local instances named iport).  The duplicate '->owning_port' and
'->isci_port' in both isci_phy and isci_remote_device will be fixed in a later
patch... this is just the straightforward rename/unification.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
76802ce675 isci: fix scic_sds_remote_device_terminate_requests
Commit 0815632 "isci: unify remote_device stop_handlers" introduced the
possibility that not all requests get terminated if we reach the
request_count.  Now that we properly reference count devices we don't
need this self-defense and can do the straightforward scan of all active
requests.

Reported-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Acked-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
852809559e isci: unify isci_phy and scic_sds_phy
They are one in the same object so remove the distinction.  The near
duplicate fields (owning_port, and isci_port) will be cleaned up
after the scic_sds_port isci_port unification.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
5076a1a97e isci: unify isci_request and scic_sds_request
They are one in the same object so remove the distinction.  The near
duplicate fields (owning_controller, and isci_host) will be cleaned up
after the scic_sds_contoller isci_host unification.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:52 -07:00
Dan Williams
ba7cb22342 isci: rename / clean up scic_sds_stp_request
* Rename scic_sds_stp_request to isci_stp_request
* Remove the unused fields and union indirection

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
db05625098 isci: preallocate requests
the dma_pool interface is optimized for object_size << page_size which
is not the case with isci_request objects and the dma_pool routines show
up in the top of the profile.

The old io_request_table which tracked whether tci slots were in-flight
or not is replaced with an IREQ_ACTIVE flag per request.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
38d8879bae isci: combine request flags
Combine three bools into one unsigned long 'flags'.  Doesn't increase the
request size due to packing. (to do: optimize the structure layout).

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
312e0c2455 isci: unify can_queue tracking on the tci_pool, uplevel tag assignment
The tci_pool tracks our outstanding command slots which are also the 'index'
portion of our tags.  Grabbing the tag early in ->lldd_execute_task let's us
drop the isci_host_can_queue() and ->was_tag_assigned_by_user infrastructure.
->was_tag_assigned_by_user required the task context to be duplicated in
request-local buffer.  With the tci established early we can build the
task_context directly into its final location and skip a memcpy.

With the task context buffer at a known address at request construction we
have the opportunity/obligation to also fix sgl handling.  This rework feels
like it belongs in another patch but the sgl handling and task_context are too
intertwined.
1/ fix the 'ab' pair embedded in the task context to point to the 'cd' pair in
   the task context (previously we were prematurely linking to the staging
   buffer).
2/ fix the broken iteration of pio sgls that assumes all sgls are relative to
   the request, and does a dangerous looking reverse lookup of physical
   address to virtual address.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Jeff Skirvin
9274f45ea5 isci: Terminate dev requests on FIS err bit rx in NCQ
When the remote device transitions to a not-ready state because of
an NCQ error condition, all outstanding requests to that device
are terminated and completed to libsas on the normal path.  The
device then waits for a READ LOG EXT command to issue on the task
management path.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
4cffe13e0d isci: fix frame received locking
Updates to the frame_rcvd before need to be atomic with respect to when
they are evaluated by libsas.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Maciej Patelczyk
7cafbf1bd5 isci: possible buffer overflow in isci_parse_oem_parameters fixed
scu_index is a parameter of isci_parse_eom_parameters and is an index
in controller table. There is a check: scu_index > SCI_MAX_CONTROLLERS
which is insufficient and should be: scu_index >= SCI_MAX_CONTROLLERS.
scu_index is used as an index in the table which size is
SCI_MAX_CONTROLLERS.

Signed-off-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
086a0dabc5 isci: fix isci_task_execute_tmf completion
1/ fix the timeout for wait_for_completion_timeout
2/ In the tmf timeout case we need to wait for our termination callback
3/ Once the request is successfully started it will be freed according to the
   normal lifetime for requests.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
e9bf709564 isci: fix support for arbitrarily large smp requests
Instead of duplicating the smp request buffer reuse the one provided by
libsas.  This future proofs the driver to support arbitrarily large smp
requests, and shrinks the request structure size by ~700 bytes.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
ddcc7e347a isci: fix dma_unmap_sg usage
One bug and a cleanup:
1/ Fix cases where we were unmapping invalid addresses (smp requests were
   being unmapped)

[  604.662770] ------------[ cut here ]------------
[  604.668026] WARNING: at lib/dma-debug.c:800 check_unmap+0x418/0x740()
[  604.675315] Hardware name: SandyBridge Platform
[  604.680465] isci 0000:03:00.0: DMA-API: device driver tries to free an invalid DMA memory address

2/ The unmap routine is too large to be an inline function, and
   isci_request_io_request_get_next_sge is unused.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
5edc33480c isci: fix smp response frame overrun
Due to a typo we currently copy way too much when copying over the
response data, but since a request is likely backed by a full page
allocation we don't corrupt live data.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
ff60639dc9 isci: kill device_sequence
Now that we have upleveled device reassignment protection to the
isci_remote_device reference count we no longer need this level of
self-defense.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
f208826751 isci: kill isci_remote_device_change_state()
Now that "stopping/stopped" are one in the same and signalled by a NULL device
pointer the rest of the device status infrastructure can be removed (->status
and ->state_lock).  The "not ready for i/o state" is replaced with a state
flag, and is evaluated under scic_lock so that we don't see transients from
taking the device reference to submitting the i/o.

This also fixes a potential leakage of can_queue slots in the rare case that
SAS_TASK_ABORTED is set at submission.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
209fae14fa isci: atomic device lookup and reference counting
We have unsafe references to remote devices that are notified to
disappear at lldd_dev_gone.  In order to clean this up we need a single
canonical source for device lookups and stable references once a lookup
succeeds.  Towards that end guarantee that domain_device.lldd_dev is
NULL as soon as we start the process of stopping a device.  Any code
path that wants to safely lookup a remote device must do so through
task->dev->lldd_dev (isci_lookup_device()).

For in-flight references outside of scic_lock we need reference counting
to ensure that the device is not recycled before we are done with it.
Simplify device back references to just scic_sds_request.target_device
which is now the only permissible internal reference that is maintained
relative to the reference count.

There were two occasions where we wanted new i/o's to be treated as
SAS_TASK_UNDELIVERED but where the domain_dev->lldd_dev link is still
intact.  Introduce a 'gone' flag to prevent i/o while waiting for libsas
to take action on the port down event.

One 'core' leftover is that we currently call
scic_remote_device_destruct() from isci_remote_device_deconstruct()
which is called when the 'core' says the device is stopped.  It would be
more natural for the final put to trigger
isci_remote_device_deconstruct() but this implementation is deferred as
it requires other changes.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
360b03ed17 isci: fix ssp response iu buffer size in isci_tmf
In isci_task_request_complete() we save the response/sense data from the
command.  Make sure isci_tmf has enough space to hold the full response.

[ it does not look like we actually use this data, and
  response_data_len/sense_data_len should be specifying the byte count,
  in any event do the simple fix first so we don't corrupt memory ]

Reported-by: Adam Gruchala <adam.gruchala@intel.com>
Tested-by: Edmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
0d0cf14c9b isci: cleanup request allocation
Rather than return an error code and update a pointer that was passed by
reference just return the request object directly (or null if allocation
failed).

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
994a9303d3 isci: cleanup/optimize queue increment macros
Every single i/o or event completion incurs a test and branch to see if
the cycle bit changed.  For power-of-2 queue sizes the cycle bit can be
read directly from the rollover of the queue pointer.

Likely premature optimization, but the hidden if() and hidden
assignments / side-effects in the macros were already asking to be
cleaned up.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00
Dan Williams
dd047c8e2b isci: cleanup tag macros
A tag is a 16 bit number where the upper four bits is a sequence number
and the remainder is the task context index (tci).  Sanitize the macro
names and shave 256-bytes out of scic_sds_controller by reducing the size of
io_request_sequence.

scic_sds_io_tag_construct --> ISCI_TAG
scic_sds_io_tag_get_sequence --> ISCI_TAG_SEQ
scic_sds_io_tag_get_index() --> ISCI_TAG_TCI
scic_sds_io_sequence_increment() [delete / open code]

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
2011-07-03 04:04:51 -07:00