scsi: isci: Fix an error code problem in isci_io_request_build()

Clang static complains that Value stored to 'status' is never read. Return
'status' rather than 'SCI_SUCCESS'.

Fixes: f1f52e75939b ("isci: uplevel request infrastructure")
Signed-off-by: Su Hui <suhui@nfschina.com>
Link: https://lore.kernel.org/r/20240112041926.3924315-1-suhui@nfschina.com
Reviewed-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Remove redundant check in isci_task_request_build()

sci_task_request_construct_ssp() has invariant return. Change this function
to void and get rid of unnecessary checks.

Found by Linux Verification Center (linuxtesting.org) with SVACE.

Signed-off-by: Artem Chernyshev <artem.chernyshev@red-soft.ru>
Link: https://lore.kernel.org/r/20231128121159.2373975-1-artem.chernyshev@red-soft.ru
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Delete sas_ssp_task.task_prio

Since libsas was introduced in commit 2908d778ab3e ("[SCSI] aic94xx: new
driver"), sas_ssp_task.task_prio is never set, so delete it and any
references which depend on it being set (all of them).

Signed-off-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20230815115156.343535-8-john.g.garry@oracle.com
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Fix typo in comment

Spelling mistake (triple letters) in comment. Detected with the help of
Coccinelle.

Link: https://lore.kernel.org/r/20220521111145.81697-91-Julia.Lawall@inria.fr
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Use enum for response frame DATAPRES field

As defined in table 126 of the SAS spec 1.1, use an enum for the DATAPRES
field, which makes reading the code easier.

Also change sas_ssp_task_response() to use a switch statement, which is
more suitable (than if-else), as suggested by Christoph.

Link: https://lore.kernel.org/r/1645112566-115804-3-git-send-email-john.garry@huawei.com
Suggested-by: Xiang Chen <chenxiang66@hisilicon.com>
Tested-by: Yihang Li <liyihang6@hisilicon.com>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Drop SAS_TASK_AT_INITIATOR

This flag is now only ever set, so delete it.

This also avoids a use-after-free in the pm8001 queue path, as reported in
the following:

https://lore.kernel.org/linux-scsi/c3cb7228-254e-9584-182b-007ac5e6fe0a@huawei.com/T/#m28c94c6d3ff582ec4a9fa54819180740e8bd4cfb

https://lore.kernel.org/linux-scsi/0cc0c435-b4f2-9c76-258d-865ba50a29dd@huawei.com/

[mkp: checkpatch + two SAS_TASK_AT_INITIATOR references]

Link: https://lore.kernel.org/r/1644489804-85730-3-git-send-email-john.garry@huawei.com
Reviewed-by: Damien Le Moal <damien.lemoal@wdc.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Drop SAS_TASK_AT_INITIATOR check in isci_task_abort_task()

In the queue path, move around when we assign sas_task->lldd_task such that
this pointer and the SAS_TASK_AT_INITIATOR flag are set atomically. It is
also not required to clear SAS_TASK_AT_INITIATOR in isci_task_execute_task()
error path as it is also cleared immediately after in isci_task_refuse()
call.

Now the following items may be considered:

- SAS_TASK_STATE_DONE and SAS_TASK_AT_INITIATOR are mutually exclusive
apart from possibly when SAS_TASK_STATE_DONE is set in
sas_scsi_find_task(), but that is after .lldd_abort_task, i.e. the
considered callback, is called.

- If isci_task_refuse() is called in the queue path, then
sas_task->lldd_task and SAS_TASK_AT_INITIATOR are cleared atomically in
isci_task_refuse().

- In the completion path, SAS_TASK_STATE_DONE is set and
SAS_TASK_AT_INITIATOR is cleared atomically before the
sas_task.lldd_task is cleared later.

So in isci_task_abort_task() if SAS_TASK_STATE_DONE is not set and
sas_task.lldd_task is still set, then SAS_TASK_AT_INITIATOR must be set -
so we can drop this check on SAS_TASK_AT_INITIATOR.

[mkp: checkpatch]

Link: https://lore.kernel.org/r/1644489804-85730-2-git-send-email-john.garry@huawei.com
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Use the proper SCSI midlayer interfaces for PI

Use scsi_prot_ref_tag() instead of scsi_get_lba() to get the reference tag
for a given I/O.

Link: https://lore.kernel.org/r/20210806040023.5355-3-martin.petersen@oracle.com
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Introduce more SAM status code aliases in enum exec_status

This patch prepares for converting SAM status codes into an enum. Without
this patch converting SAM status codes into an enumeration type would
trigger complaints about enum type mismatches for the SAS code.

Link: https://lore.kernel.org/r/20210524025457.11299-2-bvanassche@acm.org
Cc: Hannes Reinecke <hare@suse.com>
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Cc: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Acked-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: request: Fix doc-rot issue relating to 'ireq' param

Fixes the following W=1 kernel build warning(s):

drivers/scsi/isci/request.c:496: warning: Function parameter or member 'ireq' not described in 'scu_sata_request_construct_task_context'
drivers/scsi/isci/request.c:496: warning: Excess function parameter 'sci_req' description in 'scu_sata_request_construct_task_context'

Link: https://lore.kernel.org/r/20210317091230.2912389-28-lee.jones@linaro.org
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: request: Fix a myriad of kernel-doc issues

Fixes the following W=1 kernel build warning(s):

drivers/scsi/isci/request.c:211: warning: wrong kernel-doc identifier on line:
drivers/scsi/isci/request.c:414: warning: wrong kernel-doc identifier on line:
drivers/scsi/isci/request.c:472: warning: Function parameter or member 'ireq' not described in 'scu_ssp_task_request_construct_task_context'
drivers/scsi/isci/request.c:472: warning: expecting prototype for The(). Prototype was for scu_ssp_task_request_construct_task_context() instead
drivers/scsi/isci/request.c:501: warning: Function parameter or member 'ireq' not described in 'scu_sata_request_construct_task_context'
drivers/scsi/isci/request.c:501: warning: expecting prototype for This method is will fill in the SCU Task Context for any type of SATA(). Prototype was for scu_sata_request_construct_task_context() instead
drivers/scsi/isci/request.c:597: warning: Cannot understand *
drivers/scsi/isci/request.c:785: warning: expecting prototype for sci_req_tx_bytes(). Prototype was for SCU_TASK_CONTEXT_SRAM() instead
drivers/scsi/isci/request.c:1399: warning: Cannot understand *
drivers/scsi/isci/request.c:1446: warning: Cannot understand *
drivers/scsi/isci/request.c:2465: warning: Function parameter or member 'task' not described in 'isci_request_process_response_iu'
drivers/scsi/isci/request.c:2465: warning: Excess function parameter 'sas_task' description in 'isci_request_process_response_iu'
drivers/scsi/isci/request.c:2501: warning: Function parameter or member 'task' not described in 'isci_request_set_open_reject_status'
drivers/scsi/isci/request.c:2524: warning: Function parameter or member 'idev' not described in 'isci_request_handle_controller_specific_errors'
drivers/scsi/isci/request.c:2524: warning: Function parameter or member 'task' not described in 'isci_request_handle_controller_specific_errors'
drivers/scsi/isci/request.c:3337: warning: Function parameter or member 'idev' not described in 'isci_io_request_build'
drivers/scsi/isci/request.c:3337: warning: Excess function parameter 'sci_device' description in 'isci_io_request_build'

[mkp: fix typo reported by checkpatch]

Link: https://lore.kernel.org/r/20210317091230.2912389-21-lee.jones@linaro.org
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Cc: "James E.J. Bottomley" <jejb@linux.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Lee Jones <lee.jones@linaro.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Remove redundant initialization of variable 'status'

This patch removes unneeded return variables. It fixes the following
warning detected by coccinelle:

./drivers/scsi/isci/request.c:1483:17-23: Unneeded variable: "status".
Return "SCI_SUCCESS" on line 1503
./drivers/scsi/isci/request.c:2157:17-23: Unneeded variable: "status".
Return "SCI_SUCCESS" on line 2177

Link: https://lore.kernel.org/r/1612424915-106608-1-git-send-email-yang.lee@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Yang Li <yang.lee@linux.alibaba.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Remove the unneeded variable "status"

The variable 'status' is being initialized with SCI_SUCCESS and never
updated later with a new value. The initialization is redundant and can be
removed.

Link: https://lore.kernel.org/r/1609311860-102820-1-git-send-email-abaci-bugfix@linux.alibaba.com
Reported-by: Abaci <abaci@linux.alibaba.com>
Signed-off-by: YANG LI <abaci-bugfix@linux.alibaba.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

scsi: isci: Remove redundant initialization of variable 'status'

The variable 'status' is being initialized with a value that is never read
and it is being updated later with a new value. The initialization is
redundant and can be removed.

Link: https://lore.kernel.org/r/20200723142614.991416-1-colin.king@canonical.com
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Addresses-Coverity: ("Unused value")

scsi: libsas: aic94xx: hisi_sas: mvsas: pm8001: Use dev_is_expander()

Many times in libsas, and in LLDDs which use libsas, the check for an
expander device is re-implemented or open coded.

Use dev_is_expander() instead. We rename this from
sas_dev_type_is_expander() to not spill so many lines in referencing.

Signed-off-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Grammar s/the its/its/

Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: request: mark expected switch fall-through

In preparation to enabling -Wimplicit-fallthrough, mark switch cases where
we are expecting to fall through.

Notice that, in this particular case, a dash is added as a token in order
to separate the "Fall through" annotation from the rest of the comment on
the same line, which is what GCC is expecting to find.

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
Acked-by: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Use proper enumerated type in atapi_d2h_reg_frame_handler

Clang warns when one enumerated type is implicitly converted to another.

drivers/scsi/isci/request.c:1629:13: warning: implicit conversion from
enumeration type 'enum sci_io_status' to different enumeration type
'enum sci_status' [-Wenum-conversion]
status = SCI_IO_FAILURE_RESPONSE_VALID;
~ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/isci/request.c:1631:12: warning: implicit conversion from
enumeration type 'enum sci_io_status' to different enumeration type
'enum sci_status' [-Wenum-conversion]
status = SCI_IO_FAILURE_RESPONSE_VALID;
~ ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

status is of type sci_status but SCI_IO_FAILURE_RESPONSE_VALID is of
type sci_io_status. Use SCI_FAILURE_IO_RESPONSE_VALID, which is from
sci_status and has SCI_IO_FAILURE_RESPONSE_VALID's exact value since
that is what SCI_IO_FAILURE_RESPONSE_VALID is mapped to in the isci.h
file.

Link: https://github.com/ClangBuiltLinux/linux/issues/153
Signed-off-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: fix typo in function names

There are a couple of typos in function names and spelling of request
where the letters u and e are swapped:

scu_ssp_reqeust_construct_task_context
scu_sata_reqeust_construct_task_context

Fix the spelling of request.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: fix typo in deg_dbg message

Trivial fix to typo "repsonse" to "response" in dev_dbg message.

Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

libata/libsas: Define ATA_CMD_NCQ_NON_DATA

Define the NCQ NON DATA command and update libsas to handle it
correctly.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

libsas: enable FPDMA SEND/RECEIVE

Update libsas and dependent drivers to handle FPDMA
SEND/RECEIVE correctly.

Signed-off-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

libsas: use ata_dev_classify()

Use the ata device class from libata in libsas instead of checking
the supported command set and switch to using ata_dev_classify()
instead of our own method.

Cc: Tejun Heo <tj@kernel.org>
Cc: Dan Williams <dan.j.williams@intel.com>
Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

[SCSI] isci: fix needless ata reset escalations

isci is needlessly tying libata's hands by returning
SAM_STAT_CHECK_CONDITION to some ata errors. Instead, prefer
SAS_PROTO_RESPONSE to let libata (via sas_ata_task_done()) disposition
the device-to-host fis.

For example isci is triggering an HSM Violation where AHCI is showing a
simple media error for the same bus condition:

isci:
ata7.00: failed command: READ VERIFY SECTOR(S)
ata7.00: cmd 40/00:01:00:00:00/00:00:00:00:00/e0 tag 0
res 01/04:00:00:00:00/00:00:00:00:00/e0 Emask 0x3 (HSM violation)

ahci:
ata6.00: failed command: READ VERIFY SECTOR(S)
ata6.00: cmd 40/00:01:00:00:00/00:00:00:00:00/e0 tag 0
res 51/40:01:00:00:00/00:00:00:00:00/e0 Emask 0x9 (media error)

Note that the isci response matches this from sas_ata_task_done():
/* We saw a SAS error. Send a vague error. */
[..]
dev->sata_dev.fis[3] = 0x04; /* status err */
dev->sata_dev.fis[2] = ATA_ERR;

The end effect is that isci is needlessly triggering hard resets when
they are not necessary.

Reported-by: Xun Ni <xun.ni@intel.com>
Tested-by: Nelson Cheng <nelson.cheng@intel.com>
Acked-by: Lukasz Dorau <lukasz.dorau@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] isci: fix breakage caused by >16byte CDB patch

Oops, apparently no-one I cc'd at intel actually bothered to check this
patch for the isci driver:

commit e73823f7a2c921dcf068d34ea03bd682498d9e42
Author: James Bottomley <JBottomley@Parallels.com>
Date: Tue May 7 15:38:18 2013 -0700

[SCSI] libsas: implement > 16 byte CDB support

sci_swab32_cpy needs multiples of four, so for commands that aren't that, it's
rounding the wrong way. fix by doing (len+3)/4 instead of len/4.

Reported-by: Tony Luck <tony.luck@intel.com>
Tested-by: Tony Luck <tony.luck@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: implement > 16 byte CDB support

Remove the arbitrary expectation in libsas that all SCSI commands are 16 bytes
or less. Instead do all copies via cmd->cmd_len (and use a pointer to this in
the libsas task instead of a copy). Note that this still doesn't enable > 16
byte CDB support in the underlying drivers because their internal format has
to be fixed and the wire format of > 16 byte CDBs according to the SAS spec is
different. the libsas drivers (isci, aic94xx, mvsas and pm8xxx are all
updated for this change.

Cc: Lukasz Dorau <lukasz.dorau@intel.com>
Cc: Maciej Patelczyk <maciej.patelczyk@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Jack Wang <xjtuwjp@gmail.com>
Cc: Lindar Liu <lindar_liu@usish.com>
Cc: Xiangliang Yu <yuxiangl@marvell.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] sas: unify the pointlessly separated enums sas_dev_type and sas_device_type

These enums have been separate since the dawn of SAS, mainly because the
latter is a procotol only enum and the former includes additional state
for libsas. The dichotomy causes endless confusion about which one you
should use where and leads to pointless warnings like this:

drivers/scsi/mvsas/mv_sas.c: In function 'mvs_update_phyinfo':
drivers/scsi/mvsas/mv_sas.c:1162:34: warning: comparison between 'enum sas_device_type' and 'enum sas_dev_type' [-Wenum-compare]

Fix by eliminating one of them. The one kept is effectively the sas.h
one, but call it sas_device_type and make sure the enums are all
properly namespaced with the SAS_ prefix.

Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] isci: copy fis 0x34 response into proper buffer

SATA MICROCODE DOWNALOAD fails on isci driver. After receiving Register
Device to Host (FIS 0x34) frame Initiator resets phy.
In the frame handler routine response (FIS 0x34) was copied into wrong
buffer and upper layer did not receive any answer which resulted in
timeout and reset.
This patch corrects this bug.

Signed-off-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Signed-off-by: Lukasz Dorau <lukasz.dorau@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

treewide: fix comment/printk/variable typos

Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: Jiri Kosina <jkosina@suse.cz>

isci: Remove obviated host callback list.

Since the callbacks to libsas now occur under scic_lock, there is no
longer any reason to save the completed requests in a separate list
for completion to libsas.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Restore the ATAPI device RNC management code.

The ATAPI specific and STP general RNC suspension code had been
incorrectly removed from the remote device code.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Add protocol indicator for TMF requests.

Requests contructed as task management requests need to have the protocol
indicator set so the completion decode can observe any RNC suspension
conditions.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Save the suspension hint for upcoming suspensions.

In the case of a suspend call while in SCI_RNC_POSTING or INVALIDATING
states, the LLHANG detect needed to be saved so the upcoming suspension
would enable it correctly. The unused suspend callback parameters were
removed.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Fix the terminated I/O to not call sas_task_abort().

This addresses a regression from the commit "isci: Redesign
device suspension, abort, cleanup." in which the sas_task end
condition for terminated I/Os was made to call back on
sas_task_abort()".
This commit will be rolled into the original.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Distinguish between remote device suspension cases

For NCQ error conditions among others, there is no need to enable
the link layer hang detect timer.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Remove isci_device reqs_in_process and dev_node from isci_device.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Redesign device suspension, abort, cleanup.

This commit changes the means by which outstanding I/Os are handled
for cleanup.
The likelihood is that this commit will be broken into smaller pieces,
however that will be a later revision. Among the changes:

- All completion structures have been removed from the tmf and
abort paths.
- Now using one completed I/O list, with the I/O completed in host bit being
used to select error or normal callback paths.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Terminate outstanding TCs on TX/RX RNC suspensions.

TCs must only be terminated when RNCs are suspended.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Handle all suspending TC completions

Add comprehensive decode for all TC completions that generate RNC
suspensions.

Note that this commit also removes unconditional resumptions of ATAPI
devices when in the SCI_STP_DEV_ATAPI_ERROR state, and STP devices
when in the SCI_STP_DEV_IDLE state. This is because the SCI_STP_DEV_IDLE
and SCI_STP_DEV_ATAPI state entry functions manage the RNC resumption.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: refactor initialization for S3/S4

Based on an original implementation by Ed Nadolski and Artur Wojcik

In preparation for S3/S4 support refactor initialization so that
driver-load and resume-from-suspend can share the common init path of
isci_host_init(). Organize the initialization into objects that are
self-contained to the driver (initialized by isci_host_init) versus
those that have some upward registration (initialized at allocation time
asd_sas_phy, asd_sas_port, dma allocations). The largest change is
moving the the validation of the oem and module parameters from
isci_host_init() to isci_host_alloc().

The S3/S4 approach being taken is that libsas will be tasked with
remembering the state of the domain and the lldd is free to be
forgetful. In the case of isci we'll just re-init using a subset of the
normal driver load path.

[clean up some unused / mis-indented function definitions in host.h]

Signed-off-by: Ed Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: kill sci_phy_protocol and sci_request_protocol

Holdovers from the initial driver cleanup, replace with enum sas_protocol.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: kill ->is_direct_attached

domain_device ->parent conveys the same information.

Occurrences of ->is_direct_attached appear next to incomplete open-coded
versions of dev_is_sata(), clean those up as well.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

scsi: remove the second argument of k[un]map_atomic()

Signed-off-by: Cong Wang <amwang@redhat.com>

[SCSI] isci: debug, provide state-enum-to-string conversions

Debugging the driver requires tracing the state transtions and tracing
state names is less work than decoding numbers.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] isci: stop interpreting ->lldd_lu_reset() as an ata soft-reset

Driving resets from libsas-eh is pre-mature as libata will make a
decision about performing a softreset. Currently libata determines
whether to perform a softreset based on ata_eh_followup_srst_needed(),
and none of those conditions apply to isci.

Remove the srst implementation and translate ->lldd_lu_reset() for ata
devices as a request to drive a reset via libata-eh.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: remove ata_port.lock management duties from lldds

Each libsas driver (mvsas, pm8001, and isci) has invented a different
method for managing the ap->lock. The lock is held by the ata
->queuecommand() path. mvsas drops it prior to acquiring any internal
locks which allows it to hold its internal lock across calls to
task->task_done(). This capability is important as it is the only way
the driver can flush task->task_done() instances to guarantee that it no
longer has any in-flight references to a domain_device at
->lldd_dev_gone() time.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] isci: T10 DIF support

This allows the controller to do WRITE_INSERT and READ_STRIP for SAS
disks that support protection information. SAS disks must be formatted
with protection information to use this feature via sg_format.

sg3_utils-1.32 -- sg_format version 1.19 20110730
sg_format usage:
sg_format --format --verbose --pinfo /dev/sda

Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
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>

[SCSI] isci: Remove redundant isci_request.ttype field.

Use the existing IREQ_TMF flag as a request type indicator.

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>

[SCSI] isci: Lookup device references through requests in completions.

The LLDD needs to obtain a reference to the device through the request
itself and not through the domain_device, because the
domain_device.lldd_dev is set to NULL early in the lldd_dev_gone call.
This relies on the fact that the isci_remote_device object is keeping a
seperate reference count of outstanding requests. TODO: unify the
request count tracking with the isci_remote_device kref.

The failure signature of this condition looks like the following
log, where the important bits are the call to lldd_dev_gone followed
by a crash in isci_terminate_request_core:

[ 229.151541] isci 0000:0b:00.0: isci_remote_device_gone: domain_device = ffff8801492d4800, isci_device = ffff880143c657d0, isci_port = ffff880143c63658
[ 229.166007] isci 0000:0b:00.0: isci_remote_device_stop: isci_device = ffff880143c657d0
[ 229.175317] isci 0000:0b:00.0: isci_terminate_pending_requests: idev=ffff880143c657d0 request=ffff88014741f000; task=ffff8801470f46c0 old_state=2
[ 229.189702] isci 0000:0b:00.0: isci_terminate_request_core: device = ffff880143c657d0; request = ffff88014741f000
[ 229.201339] isci 0000:0b:00.0: isci_terminate_request_core: before completion wait (ffff88014741f000/ffff880149715ad0)
[ 229.213414] isci 0000:0b:00.0: sci_controller_process_completions: completion queue entry:0x8000a0e9
[ 229.214401] BUG: unable to handle kernel NULL pointer dereference at 0000000000000228
[ 229.214401] IP:jdskirvi-testlbo [<ffffffffa00a58be>] sci_request_completed_state_enter+0x50/0xafb [isci]
[ 229.214401] PGD 13d19e067 PUD 13d104067 PMD 0
[ 229.214401] Oops: 0000 [#1] SMP
[ 229.214401] CPU 0 x kernel: [ 226
[ 229.214401] Modules linked in: ipv6 dm_multipath uinput nouveau snd_hda_codec_realtek snd_hda_intel ttm drm_kms_helper drm snd_hda_codec snd_hwdep snd_pcm snd_timer i2c_algo_bit isci snd libsas ioatdma mxm_wmi iTCO_wdt soundcore snd_page_alloc scsi_transport_sas iTCO_vendor_support wmi dca video i2c_i801 i2c_core [last unloaded: speedstep_lib]
[ 229.214401]
[ 229.214401] Pid: 5, comm: kworker/u:0 Not tainted 3.0.0-isci-11.7.29+ #30.353196] Buffer Intel Corporation Stoakley/Pearlcity Workstation
[ 229.214401] RIP: 0010:[<ffffffffa00a58be>] I/O error on dev [<ffffffffa00a58be>] sci_request_completed_state_enter+0x50/0xafb [isci]
[ 229.214401] RSP: 0018:ffff88014fc03d20 EFLAGS: 00010046
[ 229.214401] RAX: 0000000000000000 RBX: ffff88014741f000 RCX: 0000000000000000
[ 229.214401] RDX: ffffffffa00b2c90 RSI: 0000000000000017 RDI: ffff88014741f0a0
[ 229.214401] RBP: ffff88014fc03d90 R08: 0000000000000018 R09: 0000000000000000
[ 229.214401] R10: 0000000000000000 R11: ffffffff81a17d98 R12: 000000000000001d
[ 229.214401] R13: ffff8801470f46c0 R14: 0000000000000000 R15: 0000000000008000
[ 229.214401] FS: 0000000000000000(0000) GS:ffff88014fc00000(0000) knlGS:0000000000000000
[ 229.214401] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 229.214401] CR2: 0000000000000228 CR3: 000000013ceaa000 CR4: 00000000000406f0
[ 229.214401] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 229.214401] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 229.214401] Process kworker/u:0 (pid: 5, threadinfo ffff880149714000, task ffff880149718000)
[ 229.214401] Call Trace:
[ 229.214401] <IRQ>
[ 229.214401] [<ffffffffa00aa6ce>] sci_change_state+0x4a/0x4f [isci]
[ 229.214401] [<ffffffffa00a4ca6>] sci_io_request_tc_completion+0x79c/0x7a0 [isci]
[ 229.214401] [<ffffffffa00acf35>] sci_controller_process_completions+0x14f/0x396 [isci]
[ 229.214401] [<ffffffffa00abbda>] ? spin_lock_irq+0xe/0x10 [isci]
[ 229.214401] [<ffffffffa00ad2cf>] isci_host_completion_routine+0x71/0x2be [isci]
[ 229.214401] [<ffffffff8107c6b3>] ? mark_held_locks+0x52/0x70
[ 229.214401] [<ffffffff810538e8>] tasklet_action+0x90/0xf1
[ 229.214401] [<ffffffff81054050>] __do_softirq+0xe5/0x1bf
[ 229.214401] [<ffffffff8106d9d1>] ? hrtimer_interrupt+0x129/0x1bb
[ 229.214401] [<ffffffff814ff69c>] call_softirq+0x1c/0x30
[ 229.214401] [<ffffffff8100bb67>] do_softirq+0x4b/0xa3
[ 229.214401] [<ffffffff81053d84>] irq_exit+0x53/0xb4
[ 229.214401] [<ffffffff814fffe7>] smp_apic_timer_interrupt+0x83/0x91
[ 229.214401] [<ffffffff814fee53>] apic_timer_interrupt+0x13/0x20
[ 229.214401] <EOI>
[ 229.214401] [<ffffffff814f7ad4>] ? retint_restore_args+0x13/0x13
[ 229.214401] [<ffffffff8107af29>] ? trace_hardirqs_off+0xd/0xf
[ 229.214401] [<ffffffff8104ea71>] ? vprintk+0x40b/0x452
[ 229.214401] [<ffffffff814f4b5a>] printk+0x41/0x47
[ 229.214401] [<ffffffff81314484>] __dev_printk+0x78/0x7a
[ 229.214401] [<ffffffff8131471e>] dev_printk+0x45/0x47
[ 229.214401] [<ffffffffa00ae2a3>] isci_terminate_request_core+0x15d/0x317 [isci]
[ 229.214401] [<ffffffffa00af1ad>] isci_terminate_pending_requests+0x1a4/0x204 [isci]
[ 229.214401] [<ffffffffa00229f6>] ? sas_phye_oob_error+0xc3/0xc3 [libsas]
[ 229.214401] [<ffffffffa00a7d9e>] isci_remote_device_nuke_requests+0xa6/0xff [isci]
[ 229.214401] [<ffffffffa00a811a>] isci_remote_device_stop+0x7c/0x166 [isci]
[ 229.214401] [<ffffffffa00229f6>] ? sas_phye_oob_error+0xc3/0xc3 [libsas]
[ 229.214401] [<ffffffffa00a827a>] isci_remote_device_gone+0x76/0x7e [isci]
[ 229.214401] [<ffffffffa002363e>] sas_notify_lldd_dev_gone+0x34/0x36 [libsas]
[ 229.214401] [<ffffffffa0023945>] sas_unregister_dev+0x57/0x9c [libsas]
[ 229.214401] [<ffffffffa00239c0>] sas_unregister_domain_devices+0x36/0x65 [libsas]
[ 229.214401] [<ffffffffa0022cb8>] sas_deform_port+0x72/0x1ac [libsas]
[ 229.214401] [<ffffffffa00229f6>] ? sas_phye_oob_error+0xc3/0xc3 [libsas]
[ 229.214401] [<ffffffffa0022a34>] sas_phye_loss_of_signal+0x3e/0x42 [libsas]

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>

[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>

[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>

[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>

[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>

[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>

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>

isci: merge sata.[ch] into request.c

Undo some needless separation.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

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>

isci: Handle timed-out request terminations correctly

In the situation where a termination of an I/O times-out,
make sure that the linkage from the request to the task
is severed completely. Also make sure that the selection
of tasks to terminate occurs under scic_lock.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Requests that do not start must be set to "complete"

Requests that fail at start because of a reset pending condition
must be set to complete in order to allow for later cleanup.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Add decode for SMP request retry error condition

There are situations with slow expanders in which a first attempt
to execute an SMP request will fail with a timeout. Immediate
subsequent retries will generally succeed. This change makes sure
SMP I/O failures are immediately failed to libsas so that retries
happen with no discovery process timeout delay.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: additional state machine cleanup

Additional state machine cleanups:

o Remove static functions sci_state_machine_exit_state() and
sci_state_machine_enter_state()
o Combines sci_base_state_machine_construct() and
sci_base_state_machine_start() into a single function,
sci_init_sm()
o Remove sci_base_state_machine_stop() which is unused.
o Kill state_machine.[ch]

Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
[fixed too large to inline functions]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: state machine cleanup

This cleans up several areas of the state machine mechanism:

o Rename sci_base_state_machine_change_state to sci_change_state
o Remove sci_base_state_machine_get_state function
o Rename 'state_machine' struct member to 'sm' in client structs
o Shorten the name of request states
o Shorten state machine state names as follows:
SCI_BASE_CONTROLLER_STATE_xxx to SCIC_xxx
SCI_BASE_PHY_STATE_xxx to SCI_PHY_xxx
SCIC_SDS_PHY_STARTING_SUBSTATE_xxx to SCI_PHY_SUB_xxx
SCI_BASE_PORT_STATE_xxx to SCI_PORT_xxx and
SCIC_SDS_PORT_READY_SUBSTATE_xxx to SCI_PORT_SUB_xxx
SCI_BASE_REMOTE_DEVICE_STATE_xxx to SCI_DEV_xxx
SCIC_SDS_STP_REMOTE_DEVICE_READY_SUBSTATE_xxx to SCI_STP_DEV_xxx
SCIC_SDS_SMP_REMOTE_DEVICE_READY_SUBSTATE_xxx to SCI_SMP_DEV_xxx
SCIC_SDS_REMOTE_NODE_CONTEXT_xxx_STATE to SCI_RNC_xxx

Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Removing unused variables compiler warnings

Newer gcc's are better at identifying "set, but not used" variables.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: removing the kmalloc in smp request construct

It doesn't look like there is any reason to do a kmalloc. We can do the
byte swap in place and avoid the allocation. This allow us to remove
a kmalloc and a memcpy.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: add some type safety to the state machine interface

Now that any given object type only has one state_machine we can use
container_of() to get back to the given state machine owner.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: remove the completion and event state handlers

With these handlers gone the rest of the state handler infrastructure is
removed.

Added some WARN_ONCEs where previously we would cause NULL pointer
dereferences or silently run handlers from a previous state.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: remove request task context completion state handler

Unlike the other conversions this only updates
scic_sds_io_request_tc_completion() to call the old state handlers directly
(with less verbose names). This was done for future patch readability, the
implementations have only minor differences for different completion codes.
Without a reference to the function name it would be difficult to dicern which
state is being updated. Considered changing the order to look up the
completion code before the state but that was not a clean conversion either.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: unify request frame handlers

Unify the implementation in scic_sds_io_request_frame_handler and kill
the state handler.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: unify request start handlers

Unify the implementation in scic_sds_request_start and kill the state
handler.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Piotr Sawicki <piotr.sawicki@intel.com>
[remove scic_sds_request_constructed_state_start_handler]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: unify request abort handlers

Unify the implementation in scic_sds_io_request_terminate and kill the state
handler.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: merge stp request substates into primary state machine

Remove usage of the request substate machine for stp requests, and kill
the request substate infrastructure.

Similar to the previous conversions this adds the substates to the
primary state machine and arranges for the 'started' state to transition
to the proper stp substate.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: merge smp request substates into primary state machine

Remove usage of the request substate machine for smp requests identified by:
task->task_proto == SAS_PROTOCOL_SMP

While merging over the smp_request infrastructure noticed that all the
assign buffer implementations are now equal, so moved it to
scic_sds_general_request_construct.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: merge ssp task management substates into primary state machine

Remove usage of the request substate machine for ssp task management
requests identified by:
ireq->ttype == tmf_task && dev->dev_type == SAS_END_DEV;

The only routine that checks the base 'started' state is
scic_sds_io_request_tc_completion which calls the substate machine
handler if we are not in the 'started' state or we are 'started' and no
substate machine is defined. This routine requires no conversion
because we have transitioned out of 'started' and the substate routine
will be called naturally as a result.

There are also no side effects of this conversion on exiting the
'started', state because it only stops the substate machine, which is no
longer relevant for this transaction type.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: uplevel port infrastructure

* Move port configuration agent implementation
* Merge core/scic_sds_port.[ch] into port.[ch]

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: uplevel request infrastructure

* Consolidate tiny header files
* Move files out of core/ (drop core/scic_sds_ prefix)
* Merge core/scic_sds_request.[ch] into request.[ch]
* Cleanup request.c namespace (clean forward declarations and global
namespace pollution)

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: move core/controller to host

Now that the data structures are unified unify the implementation in
host.[ch] and cleanup namespace pollution.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: unify constants

cross driver constants are spread out over multiple header files, consolidate
them into isci.h, and push some includes out to the source files that need
them.

TODO: remove SCI_MODE_SIZE infrastructure.
TODO: task.h is full of inlines that are too large

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: unify request data structures

Make scic_sds_request a proper member of isci_request. Also let's us
get rid of the dma pool object size tracking since we now know that all
requests are sizeof(isci_request). While cleaning up the construct
routine incidentally replaced SCI_FIELD_OFFSET with offsetof.

Reported-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: make command/response iu explicit request object members

Final elimination of the anonymous data at the end of the request
structure.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: make sgl explicit/aligned request object member

Towards unifying request objects we need all members to be defined in the
object and not carved out of anonymous buffer space.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Removing unnecessary functions in request.c

No need for wrappers, just access sas_task directly.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: unify isci_host data structures

Make it explicit that isci_host and scic_sds_controller are one in the same
object.

Signed-off-by: Artur Wojcik <artur.wojcik@intel.com>
[removed ->ihost back pointer]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Fixup of smp request

The struct smp_request data structure has be fixed up for Linux consumption.
This probably should go to scsi/sas.h eventually.

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Fixup SSP command IU and task IU

Fixup of SSP command IU and SSP task IU to something that looks like Linux

Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Removed sci_base_object from scic_sds_request.

The 'struct sci_base_object' was removed from the struct
scic_sds_request and was replaced by a pointer to
struct isci_request.

Signed-off-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: kill smp_discover_response_protocols in favor of domain_device.dev_type

This is step 1 of removing the contortions to:
1/ unparse expander phy data into a smp discover frame
2/ open-code-parse the smp discover fram into a domain_device.dev_type equivalent

libsas has already spent cycles determining the dev_type, so now that
scic_sds_remote_device is unified with isci_remote_device we can
directly reference dev_type.

This might also change multi-level expander detection as we previously only
looked at dev_type == EDGE_DEV and we did not consider the FANOUT_DEV case.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: move remote_device handling out of the core

Now that the core/lldd remote_device data structures are nominally unified
merge the corresponding sources into the top-level directory. Also move the
remote_node_context infrastructure which has no analog at the lldd level.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: unify remote_device data structures

Make it explicit that isci_remote_device and scic_sds_remote_device are
one in the same object.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: audit usage of BUG_ON macro in isci driver

Removes unnecessary usage of BUG_ON macro, excluding core directory.
In some cases macro is unnecesary, check is done in caller function.
In other cases macro is replaced by if construction with
appropriate warning.

Signed-off-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
[changed some survivable bug conditions to WARN_ONCE]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: fix fragile/conditional isci_host lookups

A domain_device can always reference back to ->lldd_ha unlike local lldd
structures. Fix up cases where the driver uses local objects to look up the
isci_host. This also changes the calling conventions of some routines to
expect a valid isci_host parameter rather than re-lookup the pointer on entry.

Incidentally cleans up some macros that are longer to type than the open-coded
equivalent:
isci_host_from_sas_ha
isci_dev_from_domain_dev

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Qualify when the host lock is managed for STP/SATA callbacks.

In the case of internal discovery related STP/SATA I/O started
through sas_execute_task the host lock is not taken by libsas before
calling lldd_execute_task, so the lock should not be managed before
calling back to libsas through task->task_done or sas_task_abort.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Free host lock for SATA/STP abort escalation at submission time.

In the case of I/O requests that fail at submit time because of a
pending reset condition, the host lock for SATA/STP devices must be
managed for any SCSI-initiated I/O before sas_task_abort is called.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: namespacecheck cleanups

* mark needlessly global routines static
* delete unused functions
* move kernel-doc blocks from header files to source
* reorder some functions to delete declarations
* more default handler cleanups phy

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: don't hold scic_lock over calls to sas_task_abort()

In the case where submitted I/Os fail with the status code
SCI_FAILURE_REMOTE_DEVICE_RESET_REQUIRED, the execute function now waits
until scic_lock is cleared before calling the helper function
"isci_request_signal_device_reset" which sets the flag for the pending
reset condition on the I/O.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Always set response/status for requests going into the error path.

In the case of I/O requests being failed because of a required device
reset condition, set the response and status to indicate an I/O failure.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: save the i/o tag outside the scic request structure.

The pointer to the core representation of a request is marked NULL at
completion, but we need to save the i/o tag for task management.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Jacek Danecki <Jacek.Danecki@intel.com>
[revise changelog]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Any reset indicated on an I/O completion escalates it to the error path.

If there is a pending device reset, the I/O is used to accomplish the reset by setting the
RESET bit in the task status, and then putting the task into the error handler
path using sas abort task.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Jacek Danecki <Jacek.Danecki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: fix completion / abort path.

Corrected use of the request state_lock in the completion callback.

In the case where an abort (or reset) thread is trying to terminate an
I/O request, it sets the request state to "aborting" (or "terminating")
if the state is still "starting". One of the bugs was to never set the
state to "completed". Another was to not correctly recognize the
situation where the I/O had completed but the sas_task was still pending
callback to task_done - this was typically a problem in the LUN and
device reset cases.

It is now possible that we leave isci_task_abort_task() with
request->io_request_completion pointing to localy allocated
aborted_io_completion struct. It may result in a system crash.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Maciej Trela <Maciej.Trela@intel.com>
Signed-off-by: Jacek Danecki <Jacek.Danecki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Changes in isci_host_completion_routine

Changes to move management of the reqs_in_process entry for the request here.
Made changes to note when the task is already in the abort path and
cannot be completed through callbacks.

Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Jacek Danecki <Jacek.Danecki@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: remove sci_device_handle

It belies the fact that isci_remote_device and scic_sds_remote_device
are one in same object with the same lifetime rules.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: debug fixes

Some of the chain walks to get back to our dev are invalid.

isci_remote_device_change_state: delete rather than adding conditional deref
chain walking
isci_request_change_state: fix, it was being called too early
isci_request_ssp_io_request_get_lun: fix compile breakage hidden by ifdef DEBUG

Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: kill SCI_IO_REQUEST_DATA_DIRECTION

It's an unnecessary typedef that mirrors the kernel's enum
dma_data_direction.

Also cleanup some long variable names along the way.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>

isci: Intel(R) C600 Series Chipset Storage Control Unit Driver

Support for the up to 2x4-port 6Gb/s SAS controllers embedded in the
chipset.

This is a snapshot of the first publicly available version of the driver,
commit 4c1db2d0 in the 'historical' branch.

git://git.kernel.org/pub/scm/linux/kernel/git/djbw/isci.git historical

Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dave Jiang <dave.jiang@intel.com>
Signed-off-by: Edmund Nadolski <edmund.nadolski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>