ata,scsi: remove ata_sas_port_init()

ata_sas_port_init() now only contains a single initialization.

Move this single initialization to ata_sas_port_alloc(), since:
1) ata_sas_port_alloc() already initializes some of the struct members.
2) ata_sas_port_alloc() is only used by libsas.

Suggested-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

ata,scsi: cleanup __ata_port_probe()

Rename __ata_port_probe() to ata_port_probe() and drop the wrapper
ata_sas_async_probe().

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

ata,scsi: remove ata_sas_port_destroy()

Is now a wrapper around kfree(), so call it directly.

Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

ata,scsi: remove ata_sas_port_{start,stop} callbacks

Callbacks are empty now, so remove them.

Also, remove the call to ap->ops->port_start() in ata_sas_port_init(),
as this would otherwise cause a NULL pointer dereference, now when the
callback is gone.

Signed-off-by: Hannes Reinecke <hare@suse.de>
[niklas: remove the call to ap->ops->port_start() in ata_sas_port_init()]
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <dlemoal@kernel.org>

scsi: libsas: Delete sas_ssp_task.retry_count

Since libsas was introduced in commit 2908d778ab3e ("[SCSI] aic94xx: new
driver"), sas_ssp_task.retry_count is only ever set, so delete it.

The aic94xx driver also had its own retry_count definition in struct scb
sub-structs, which may have caused a mix-up.

Signed-off-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20230815115156.343535-6-john.g.garry@oracle.com
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Delete struct scsi_core

Since commit 79855d178557 ("libsas: remove task_collector mode"), struct
scsi_core only contains a reference to the shost. struct scsi_core is only
used in sas_ha_struct.core, so delete scsi_core and replace with a
reference to the shost there.

Signed-off-by: John Garry <john.g.garry@oracle.com>
Link: https://lore.kernel.org/r/20230815115156.343535-5-john.g.garry@oracle.com
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Add return_fis_on_success to sas_ata_task

Set return_fis_on_success when libata requests result taskfile.

For Command Duration Limits policy 0xD (command completes without
an error) libata needs FIS in order to detect the ATA_SENSE bit and
read the Sense Data for Successful NCQ Commands log (0Fh).

Signed-off-by: Igor Pylypiv <ipylypiv@google.com>
Link: https://lore.kernel.org/r/20230819213040.1101044-2-ipylypiv@google.com
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: Damien Le Moal <dlemoal@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Fix an error code in sas_ata_add_dev()

This code accidentally returns success instead of -ENOMEM.

Fixes: 7cc7646b4b24 ("scsi: libsas: Factor out sas_ata_add_dev()")
Link: https://lore.kernel.org/r/Y7asLxzVwQ56G+ya@kili
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

ata: libata: simplify qc_fill_rtf port operation interface

The boolean return value of the qc_fill_rtf operation is used nowhere.
Simplify this operation interface by making it a void function. All
drivers defining this operation are also updated.

Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>

ata: scsi: rename flag ATA_QCFLAG_FAILED to ATA_QCFLAG_EH

The name ATA_QCFLAG_FAILED is misleading since it does not mean that a
QC completed in error, or that it didn't complete at all. It means that
libata decided to schedule EH for the QC, so the QC is now owned by the
libata error handler (EH).

The normal execution path is responsible for not accessing a QC owned
by EH. libata core enforces the rule by returning NULL from
ata_qc_from_tag() for QCs owned by EH.

It is quite easy to mistake that a QC marked with ATA_QCFLAG_FAILED was
an error. However, a QC that was actually an error is instead indicated
by having qc->err_mask set. E.g. when we have a NCQ error, we abort all
QCs, which currently will mark all QCs as ATA_QCFLAG_FAILED. However, it
will only be a single QC that is an error (i.e. has qc->err_mask set).

Rename ATA_QCFLAG_FAILED to ATA_QCFLAG_EH to more clearly highlight that
this flag simply means that a QC is now owned by EH. This new name will
not mislead to think that the QC was an error (which is instead
indicated by having qc->err_mask set).

This also makes it more obvious that the EH code skips all QCs that do
not have ATA_QCFLAG_EH set (rather than ATA_QCFLAG_FAILED), since the EH
code should simply only care about QCs that are owned by EH itself.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

scsi: libsas: Factor out sas_ata_add_dev()

Factor out sas_ata_add_dev() and put it in sas_ata.c since it is a SATA
related interface. Also follow the standard coding style to define an
inline empty function when CONFIG_SCSI_SAS_ATA is not enabled.

Cc: John Garry <john.g.garry@oracle.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Move sas_get_ata_command_set() up to save the declaration

There is a sas_get_ata_command_set() declaration above sas_get_ata_info()
to make it compile. However, this function is defined in the same
file. Move it up to save the forward declaration.

Also remove the variable 'fis' which is not needed in this function.

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

scsi: libsas: Grab the ATA port lock in sas_ata_device_link_abort()

Grab the ATA port lock in sas_ata_device_link_abort() before calling
ata_link_abort() as outlined in this function's locking requirements.

Fixes: 44112922674b ("scsi: libsas: Add sas_ata_device_link_abort()")
Signed-off-by: Xingui Yang <yangxingui@huawei.com>
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Do not export sas_ata_wait_after_reset()

sas_ata_wait_after_reset() does not need to be exported since it is no
longer referenced outside libsas.

Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com>
Link: https://lore.kernel.org/r/20221118083714.4034612-6-zhanjie9@hisilicon.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Add smp_ata_check_ready_type()

Create function smp_ata_check_ready_type() for LLDDs to wait for SATA
devices to come up after a link reset.

Signed-off-by: Jie Zhan <zhanjie9@hisilicon.com>
Link: https://lore.kernel.org/r/20221118083714.4034612-4-zhanjie9@hisilicon.com
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Update SATA dev FIS in sas_ata_task_done()

In sas_ata_task_done(), for commands which complete with error we set the
SATA dev FIS status field with ATA_ERR. In ata_eh_analyze_tf() this would
be interpreted as a HSM error. Set ATA_DRDY, which will lead libata to
judge as a device error, which is a safer bet.

Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1665998435-199946-9-git-send-email-john.garry@huawei.com
Reviewed-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Add sas_ata_device_link_abort()

Similar to how AHCI handles NCQ errors in ahci_error_intr() ->
ata_port_abort() -> ata_do_link_abort(), add an NCQ error handler for LLDDs
to call to initiate a link abort.

This will mark all outstanding QCs as failed and kick-off EH.

Note:

A "force reset" argument is added for drivers which require the ATA error
handling to always reset the device.

A driver may require this feature for when SATA device per-SCSI cmnd
resources are only released during reset for ATA EH. As such, we need an
option to force reset to be done, regardless of what any EH autopsy
decides.

The SATA device FIS fields are set to indicate a device error from
ata_eh_analyze_tf().

Suggested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Suggested-by: Niklas Cassel <niklas.cassel@wdc.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1665998435-199946-2-git-send-email-john.garry@huawei.com
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Tested-by: Niklas Cassel <niklas.cassel@wdc.com> # pm80xx
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: make use of ata_port_is_frozen() helper

Clean up the code by making use of the newly introduced
ata_port_is_frozen() helper function.

Signed-off-by: Niklas Cassel <niklas.cassel@wdc.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Acked-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>

scsi: libsas: Refactor sas_ata_hard_reset()

Create function sas_ata_wait_after_reset() from sas_ata_hard_reset() as
some LLDDs may want to check for a remote ATA phy is up after reset.

Link: https://lore.kernel.org/r/1652354134-171343-2-git-send-email-john.garry@huawei.com
Tested-by: Yihang Li <liyihang6@hisilicon.com>
Reviewed-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Simplify sas_ata_qc_issue() detection of NCQ commands

To detect if a command is NCQ, there is no need to test all possible NCQ
command codes. Instead, use ata_is_ncq() to test the command protocol.

Link: https://lore.kernel.org/r/20220220031810.738362-24-damien.lemoal@opensource.wdc.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Fix sas_ata_qc_issue() handling of NCQ NON DATA commands

To detect for the DMA_NONE (no data transfer) DMA direction,
sas_ata_qc_issue() tests if the command protocol is ATA_PROT_NODATA. This
test does not include the ATA_CMD_NCQ_NON_DATA command as this command
protocol is defined as ATA_PROT_NCQ_NODATA (equal to ATA_PROT_FLAG_NCQ) and
not as ATA_PROT_NODATA.

To include both NCQ and non-NCQ commands when testing for the DMA_NONE DMA
direction, use "!ata_is_data()".

Link: https://lore.kernel.org/r/20220220031810.738362-2-damien.lemoal@opensource.wdc.com
Fixes: 176ddd89171d ("scsi: libsas: Reset num_scatter if libata marks qc as NODATA")
Cc: stable@vger.kernel.org
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jack Wang <jinpu.wang@ionos.com>
Signed-off-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Add sas_execute_ata_cmd()

Add a function to execute an ATA command using the TMF code, and use in the
hisi_sas driver. That driver needs to be able to issue the command on a
specific phy, so add an interface for that.

With that, hisi_sas_exec_internal_tmf_task() may be deleted.

Link: https://lore.kernel.org/r/1645534259-27068-19-git-send-email-john.garry@huawei.com
Tested-by: Yihang Li <liyihang6@hisilicon.com>
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Delete SAS_SG_ERR

No LLDD sets exec status as SAS_SG_ERR, so remove support.

Link: https://lore.kernel.org/r/1645112566-115804-5-git-send-email-john.garry@huawei.com
Tested-by: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Remove unused parameter for function sas_ata_eh()

Input parameter work_q is not unused in function sas_ata_eh(), so remove
it.

Link: https://lore.kernel.org/r/1644561778-183074-4-git-send-email-chenxiang66@hisilicon.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Remove duplicated setting for task->task_state_flags

Task->task_state_flags is already set in function sas_alloc_task(), so
remove duplicated setting.

Link: https://lore.kernel.org/r/1644561778-183074-3-git-send-email-chenxiang66@hisilicon.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Use scsi_cmd_to_rq() instead of scsi_cmnd.request

Prepare for removal of the request pointer by using scsi_cmd_to_rq()
instead. This patch does not change any functionality.

Link: https://lore.kernel.org/r/20210809230355.8186-27-bvanassche@acm.org
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Allow libsas to include SCSI header files directly

libsas needs to include some header files in the scsi directory. However
these are currently hardcoded with the path "../" in the C files. Do this
in the Makefile to avoid hardcoding the path.

Link: https://lore.kernel.org/r/20210716074551.771312-1-yanaijie@huawei.com
Cc: John Garry <john.garry@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
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: libsas: Correctly indent statements in sas_to_ata_err()

checkpatch reported an error in sas_to_ata_err(). switch and case
statements are incorrectly indented.

Link: https://lore.kernel.org/r/1616675396-6108-2-git-send-email-luojiaxing@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Reset num_scatter if libata marks qc as NODATA

When the cache_type for the SCSI device is changed, the SCSI layer issues a
MODE_SELECT command. The caching mode details are communicated via a
request buffer associated with the SCSI command with data direction set as
DMA_TO_DEVICE (scsi_mode_select()). When this command reaches the libata
layer, as a part of generic initial setup, libata layer sets up the
scatterlist for the command using the SCSI command (ata_scsi_qc_new()).
This command is then translated by the libata layer into
ATA_CMD_SET_FEATURES (ata_scsi_mode_select_xlat()). The libata layer treats
this as a non-data command (ata_mselect_caching()), since it only needs an
ATA taskfile to pass the caching on/off information to the device. It does
not need the scatterlist that has been setup, so it does not perform
dma_map_sg() on the scatterlist (ata_qc_issue()). Unfortunately, when this
command reaches the libsas layer (sas_ata_qc_issue()), libsas layer sees it
as a non-data command with a scatterlist. It cannot extract the correct DMA
length since the scatterlist has not been mapped with dma_map_sg() for a
DMA operation. When this partially constructed SAS task reaches pm80xx
LLDD, it results in the following warning:

"pm80xx_chip_sata_req 6058: The sg list address
start_addr=0x0000000000000000 data_len=0x0end_addr_high=0xffffffff
end_addr_low=0xffffffff has crossed 4G boundary"

Update libsas to handle ATA non-data commands separately so num_scatter and
total_xfer_len remain 0.

Link: https://lore.kernel.org/r/20210318225632.2481291-1-jollys@google.com
Fixes: 53de092f47ff ("scsi: libsas: Set data_dir as DMA_NONE if libata marks qc as NODATA")
Tested-by: Luo Jiaxing <luojiaxing@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Jolly Shah <jollys@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Simplify the return expression of sas_discover_* functions

Simplify the return expression.

Link: https://lore.kernel.org/r/20200921134558.3478922-1-liushixin2@huawei.com
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Liu Shixin <liushixin2@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Set data_dir as DMA_NONE if libata marks qc as NODATA

It was discovered that sdparm will fail when attempting to disable write
cache on a SATA disk connected via libsas.

In the ATA command set the write cache state is controlled through the SET
FEATURES operation. This is roughly corresponds to MODE SELECT in SCSI and
the latter command is what is used in the SCSI-ATA translation layer. A
subtle difference is that a MODE SELECT carries data whereas SET FEATURES
is defined as a non-data command in ATA.

Set the DMA data direction to DMA_NONE if the requested ATA command is
identified as non-data.

[mkp: commit desc]

Fixes: fa1c1e8f1ece ("[SCSI] Add SATA support to libsas")
Link: https://lore.kernel.org/r/1598426666-54544-1-git-send-email-luojiaxing@huawei.com
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.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: libsas: Check link status in ATA prereset()

libata currently attempts to reset even if the SATA disk is unplugged. To
avoid the meaningless reset of a missing disk, libsas should report offline
status to libata. libata already provides a .prereset callback for this
purpose. This is called by ata_eh_reset() and can be used to influence
whether a reset attempt should be made.

Add sas_ata_preset callback to check status of phy and disk. If the disk is
already offline or phy is disabled, we return -ENOENT to libata to avoid
the reset.

Link: https://lore.kernel.org/r/1595408643-63011-3-git-send-email-luojiaxing@huawei.com
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Remove postreset from sas_sata_ops

sas_sata_ops uses ata_std_postreset as .postreset callback. However,
ata_std_postreset() calls sata_scr_read()/sata_scr_write() which need to
access the ATA SCR register. This register not available in the libsas case
and the functions always return -EOPNOTSUPP.

Drop the .postreset callback.

Link: https://lore.kernel.org/r/1595408643-63011-2-git-send-email-luojiaxing@huawei.com
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Add missing annotation for sas_ata_qc_issue()

Sparse reports a warning at sas_ata_qc_issue()

warning: context imbalance in sas_ata_qc_issue() - unexpected unlock
The root cause is the missing annotation at sas_ata_qc_issue()

Add the missing __must_hold(ap->lock) annotation

Link: https://lore.kernel.org/r/20200411001933.10072-7-jbi.octave@gmail.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Jules Irenge <jbi.octave@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Tidy SAS address print format

Currently we use a mixture of %016llx, %llx, and %16llx when printing a SAS
address.

Since the most significant nibble of the SAS address is always 5 - as per
standard - this formatting is not so important; but some fake SAS addresses
for SATA devices may not be. And we have mangled/invalid address to
consider also. And it's better to be consistent in the code, so use a fixed
format.

The SAS address is a fixed size at 64b, so we want to 0 byte extend to 16
nibbles, so use %016llx globally.

Also make some prints to be explicitly hex, and tidy some whitespace issue.

Link: https://lore.kernel.org/r/1576758957-227350-1-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>

treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 156

Based on 1 normalized pattern(s):

this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license as published by
the free software foundation either version 2 of the license or at
your option any later version this program is distributed in the
hope that it will be useful but without any warranty without even
the implied warranty of merchantability or fitness for a particular
purpose see the gnu general public license for more details you
should have received a copy of the gnu general public license along
with this program if not write to the free software foundation inc
59 temple place suite 330 boston ma 02111 1307 usa

extracted by the scancode license scanner the SPDX license identifier

GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1334 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Richard Fontana <rfontana@redhat.com>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527070033.113240726@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

scsi: libsas: switch sas_ata.[ch] to SPDX tags

Use the the GPLv2+ SPDX tag instead of verbose boilerplate text.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Print expander PHY indexes in decimal

Currently we print expander PHY indexes in a mix of decimal and hex.

It is more consistent and also more convenient to read decimal, so
make this change.

We use width of 2 for expander and 1 for root PHYs prints.

Some lines which were needlessly spilling multiple lines are unified.

Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Drop SAS_DPRINTK() and revise logs levels

Like sas_printk() did previously, SAS_DPRINTK() offers little value now
that libsas logs already have the "sas" prefix through pr_fmt(fmt). So it
can be dropped.

However, after reviewing some logs in libsas, it is noticed that debug
level is too low in many instances.

So this change drops SAS_DPRINTK() and revises some logs to a more
appropriate level. However many stay at debug level, although some
are significantly promoted.

We add -DDEBUG for compilation so that we keep the debug messages by
default, as before.

All the pre-existing checkpatch errors for spanning messages across
multiple lines are also fixed.

Finally, all other references to printk() [apart from special formatting
in sas_ata.c] are removed and replaced with appropriate pr_xxx().

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Use pr_fmt(fmt)

In preparation for dropping the libsas printk wrappers, use pr_fmt(fmt)
declaration to add the framework log prefix - "sas".

Suggested-by: Joe Perches <joe@perches.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

block: don't hold the queue_lock over blk_abort_request

There is nothing it could synchronize against, so don't go through
the pains of acquiring the lock.

Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>

scsi: libsas: check the ata device status by ata_dev_enabled()

When ata device IDENTIFY failed, the ata device status is ATA_DEV_UNKNOWN. The
libata reported like:

[113518.620433] ata5.00: qc timeout (cmd 0xec)
[113518.653646] ata5.00: failed to IDENTIFY (I/O error, err_mask=0x4)

But libsas verifies the device status by ata_dev_disabled(), which skipped
ATA_DEV_UNKNOWN. This will make libsas think the ata device probing succeed
the device cannot be actually brought up. And even the new bcast of this
device will be considered as flutter and will not probe this device again.

Change ata_dev_disabled() to !ata_dev_enabled() so that libsas can deal with
this if the ata device probe failed. New bcasts can let us try to probe the
device again and bring it up if it is fine to IDENTIFY.

Tested-by: Zhou Yupeng <zhouyupeng1@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
CC: John Garry <john.garry@huawei.com>
CC: Johannes Thumshirn <jthumshirn@suse.de>
CC: Ewan Milne <emilne@redhat.com>
CC: Christoph Hellwig <hch@lst.de>
CC: Tomas Henzl <thenzl@redhat.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: Hannes Reinecke <hare@suse.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: dynamically allocate and free ata host

Commit 2623c7a5f2 ("libata: add refcounting to ata_host") v4.17+ introduced
refcounting to ata_host and will increase or decrease the refcount when
adding or deleting transport ATA port.

Now the ata host for libsas is embedded in domain_device, and the ->kref
member is not initialized. Afer we add ata transport class, ata_host_get()
will be called when adding transport ATA port and a warning will be
triggered as below:

refcount_t: increment on 0; use-after-free.
WARNING: CPU: 2 PID: 103 at
lib/refcount.c:153 refcount_inc+0x40/0x48 ...... Call trace:
refcount_inc+0x40/0x48
ata_host_get+0x10/0x18
ata_tport_add+0x40/0x120
ata_sas_tport_add+0xc/0x14
sas_ata_init+0x7c/0xc8
sas_discover_domain+0x380/0x53c
process_one_work+0x12c/0x288
worker_thread+0x58/0x3f0
kthread+0xfc/0x128
ret_from_fork+0x10/0x18

And also when removing transport ATA port ata_host_put() will be called and
another similar warning will be triggered. If the refcount decreased to
zero, the ata host will be freed. But this ata host is only part of
domain_device, it cannot be freed directly.

So we have to change this embedded static ata host to a dynamically
allocated ata host and initialize the ->kref member. To use ata_host_get()
and ata_host_put() in libsas, we need to move the declaration of these
functions to the public libata.h and export them.

Fixes: b6240a4df018 ("scsi: libsas: add transport class for ATA devices")
Signed-off-by: Jason Yan <yanaijie@huawei.com>
CC: John Garry <john.garry@huawei.com>
CC: Taras Kondratiuk <takondra@cisco.com>
CC: Tejun Heo <tj@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: remove irq save in sas_ata_qc_issue()

Since commit 312d3e56119a ("[SCSI] libsas: remove ata_port.lock management
duties from lldds") the sas_ata_qc_issue() function unlocks the
ata_port.lock and disables interrupts before doing so. That lock is always
taken with disabled interrupts so at this point, the interrupts are already
disabled. There is no need to disable the interrupts before the unlock
operation because they are already disabled. Restoring the interrupt state
later does not change anything because they were disabled and remain
disabled. Therefore remove the operations which do not change the
behaviour.

Fixes: 312d3e56119a ("[SCSI] libsas: remove ata_port.lock management duties from lldds")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: add transport class for ATA devices

Now ata devices attached with sas controller do not have transport
class, so that we can not see any information of these ata devices in
/sys/class/ata_port(or ata_link or ata_device).

Add transport class for the ata devices attached with sas controller.
The /sys/class directory will show the infomation of the ata devices
as follows:

localhost:/sys/class # ls ata*
ata_device:
dev1.0 dev2.0

ata_link:
link1 link2

ata_port:
ata1 ata2

No functional change of the device scanning and io path. The ata
transport class was deleted when destroying the sas devices.

Signed-off-by: Jason Yan <yanaijie@huawei.com>
CC: Dan Williams <dan.j.williams@intel.com>
CC: Tejun Heo <tj@kernel.org>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Fix kernel-doc headers

Avoid that building with W=1 causes the kernel-doc tool to complain
about function arguments that have not been documented in the libsas
kernel-doc headers. Avoid that the short description starts with a
hyphen by changing "--" into "-" in the first line of the kernel-doc
headers.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: John Garry <john.garry@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: direct call probe and destruct

In commit 87c8331fcf72 ("[SCSI] libsas: prevent domain rediscovery
competing with ata error handling") introduced disco mutex to prevent
rediscovery competing with ata error handling and put the whole
revalidation in the mutex. But the rphy add/remove needs to wait for the
error handling which also grabs the disco mutex. This may leads to dead
lock.So the probe and destruct event were introduce to do the rphy
add/remove asynchronously and out of the lock.

The asynchronously processed workers makes the whole discovery process
not atomic, the other events may interrupt the process. For example,
if a loss of signal event inserted before the probe event, the
sas_deform_port() is called and the port will be deleted.

And sas_port_delete() may run before the destruct event, but the
port-x:x is the top parent of end device or expander. This leads to
a kernel WARNING such as:

[ 82.042979] sysfs group 'power' not found for kobject 'phy-1:0:22'
[ 82.042983] ------------[ cut here ]------------
[ 82.042986] WARNING: CPU: 54 PID: 1714 at fs/sysfs/group.c:237
sysfs_remove_group+0x94/0xa0
[ 82.043059] Call trace:
[ 82.043082] [<ffff0000082e7624>] sysfs_remove_group+0x94/0xa0
[ 82.043085] [<ffff00000864e320>] dpm_sysfs_remove+0x60/0x70
[ 82.043086] [<ffff00000863ee10>] device_del+0x138/0x308
[ 82.043089] [<ffff00000869a2d0>] sas_phy_delete+0x38/0x60
[ 82.043091] [<ffff00000869a86c>] do_sas_phy_delete+0x6c/0x80
[ 82.043093] [<ffff00000863dc20>] device_for_each_child+0x58/0xa0
[ 82.043095] [<ffff000008696f80>] sas_remove_children+0x40/0x50
[ 82.043100] [<ffff00000869d1bc>] sas_destruct_devices+0x64/0xa0
[ 82.043102] [<ffff0000080e93bc>] process_one_work+0x1fc/0x4b0
[ 82.043104] [<ffff0000080e96c0>] worker_thread+0x50/0x490
[ 82.043105] [<ffff0000080f0364>] kthread+0xfc/0x128
[ 82.043107] [<ffff0000080836c0>] ret_from_fork+0x10/0x50

Make probe and destruct a direct call in the disco and revalidate function,
but put them outside the lock. The whole discovery or revalidate won't
be interrupted by other events. And the DISCE_PROBE and DISCE_DESTRUCT
event are deleted as a result of the direct call.

Introduce a new list to destruct the sas_port and put the port delete after
the destruct. This makes sure the right order of destroying the sysfs
kobject and fix the warning above.

In sas_ex_revalidate_domain() have a loop to find all broadcasted
device, and sometimes we have a chance to find the same expander twice.
Because the sas_port will be deleted at the end of the whole revalidate
process, sas_port with the same name cannot be added before this.
Otherwise the sysfs will complain of creating duplicate filename. Since
the LLDD will send broadcast for every device change, we can only
process one expander's revalidation.

[mkp: kbuild test robot warning]

Signed-off-by: Jason Yan <yanaijie@huawei.com>
CC: John Garry <john.garry@huawei.com>
CC: Johannes Thumshirn <jthumshirn@suse.de>
CC: Ewan Milne <emilne@redhat.com>
CC: Christoph Hellwig <hch@lst.de>
CC: Tomas Henzl <thenzl@redhat.com>
CC: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Annotate fall-through in a switch statement

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: fix ata xfer length

The total ata xfer length may not be calculated properly, in that we do
not use the proper method to get an sg element dma length.

According to the code comment, sg_dma_len() should be used after
dma_map_sg() is called.

This issue was found by turning on the SMMUv3 in front of the hisi_sas
controller in hip07. Multiple sg elements were being combined into a
single element, but the original first element length was being use as
the total xfer length.

Cc: <stable@vger.kernel.org>
Fixes: ff2aeb1eb64c8a4770a6 ("libata: convert to chained sg")
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi:libsas: fix oops caused by assigning a freed task to ->lldd_task

A freed task has been assigned to ->lldd_task when lldd_execute_task()
failed in sas_ata_qc_issue(), and access of ->lldd_task will cause an
oops:

Call trace:
[<ffffffc000641f64>] sas_ata_post_internal+0x6c/0x150
[<ffffffc0006c0d64>] ata_exec_internal_sg+0x32c/0x588
[<ffffffc0006c1048>] ata_exec_internal+0x88/0xe8
[<ffffffc0006c13b4>] ata_dev_read_id+0x204/0x5e0
[<ffffffc0006c17f0>] ata_dev_reread_id+0x60/0xc8
[<ffffffc0006c3098>] ata_dev_revalidate+0x88/0x1e0
[<ffffffc0006cf828>] ata_eh_recover+0xcf8/0x13a8
[<ffffffc0006d075c>] ata_do_eh+0x5c/0xe0
[<ffffffc0006d0828>] ata_std_error_handler+0x48/0x98
[<ffffffc0006d042c>] ata_scsi_port_error_handler+0x474/0x658
[<ffffffc000641b78>] async_sas_ata_eh+0x50/0x80
[<ffffffc0000ca664>] async_run_entry_fn+0x64/0x180
[<ffffffc0000c085c>] process_one_work+0x164/0x438
[<ffffffc0000c0c74>] worker_thread+0x144/0x4b0
[<ffffffc0000c70fc>] kthread+0xfc/0x110

Fix this by reassigning NULL to ->lldd_task in error path.

Signed-off-by: Wei Fang <fangwei1@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

libsas: use ata_is_ncq() and ata_has_dma() accessors

Use accessors instead of the raw protocol value.

Signed-off-by: Hannes Reinecke <hare@suse.com>
[hch: trivial cleanup of the ata_task assignments]
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Tejun Heo <tj@kernel.org>

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>

ata: Add a new flag to destinguish sas controller

SAS controller has its own tag allocation, which doesn't directly match to ATA
tag, so SAS and SATA have different code path for ata tags. Originally we use
port->scsi_host (98bd4be1) to destinguish SAS controller, but libsas set
->scsi_host too, so we can't use it for the destinguish, we add a new flag for
this purpose.

Without this patch, the following oops can happen because scsi-mq uses
a host-wide tag map shared among all devices with some integer tag
values >= ATA_MAX_QUEUE. These unexpectedly high tag values cause
__ata_qc_from_tag() to return NULL, which is then dereferenced in
ata_qc_new_init().

BUG: unable to handle kernel NULL pointer dereference at 0000000000000058
IP: [<ffffffff804fd46e>] ata_qc_new_init+0x3e/0x120
PGD 32adf0067 PUD 32adf1067 PMD 0
Oops: 0002 [#1] SMP DEBUG_PAGEALLOC
Modules linked in: iscsi_tcp libiscsi_tcp libiscsi scsi_transport_iscsi igb
i2c_algo_bit ptp pps_core pm80xx libsas scsi_transport_sas sg coretemp
eeprom w83795 i2c_i801
CPU: 4 PID: 1450 Comm: cydiskbench Not tainted 4.0.0-rc3 #1
Hardware name: Supermicro X8DTH-i/6/iF/6F/X8DTH, BIOS 2.1b 05/04/12
task: ffff8800ba86d500 ti: ffff88032a064000 task.ti: ffff88032a064000
RIP: 0010:[<ffffffff804fd46e>] [<ffffffff804fd46e>] ata_qc_new_init+0x3e/0x120
RSP: 0018:ffff88032a067858 EFLAGS: 00010046
RAX: 0000000000000000 RBX: ffff8800ba0d2230 RCX: 000000000000002a
RDX: ffffffff80505ae0 RSI: 0000000000000020 RDI: ffff8800ba0d2230
RBP: ffff88032a067868 R08: 0000000000000201 R09: 0000000000000001
R10: 0000000000000000 R11: 0000000000000000 R12: ffff8800ba0d0000
R13: ffff8800ba0d2230 R14: ffffffff80505ae0 R15: ffff8800ba0d0000
FS: 0000000041223950(0063) GS:ffff88033e480000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000058 CR3: 000000032a0a3000 CR4: 00000000000006e0
Stack:
ffff880329eee758 ffff880329eee758 ffff88032a0678a8 ffffffff80502dad
ffff8800ba167978 ffff880329eee758 ffff88032bf9c520 ffff8800ba167978
ffff88032bf9c520 ffff88032bf9a290 ffff88032a0678b8 ffffffff80506909
Call Trace:
[<ffffffff80502dad>] ata_scsi_translate+0x3d/0x1b0
[<ffffffff80506909>] ata_sas_queuecmd+0x149/0x2a0
[<ffffffffa0046650>] sas_queuecommand+0xa0/0x1f0 [libsas]
[<ffffffff804ea544>] scsi_dispatch_cmd+0xd4/0x1a0
[<ffffffff804eb50f>] scsi_queue_rq+0x66f/0x7f0
[<ffffffff803e5098>] __blk_mq_run_hw_queue+0x208/0x3f0
[<ffffffff803e54b8>] blk_mq_run_hw_queue+0x88/0xc0
[<ffffffff803e5c74>] blk_mq_insert_request+0xc4/0x130
[<ffffffff803e0b63>] blk_execute_rq_nowait+0x73/0x160
[<ffffffffa0023fca>] sg_common_write+0x3da/0x720 [sg]
[<ffffffffa0025100>] sg_new_write+0x250/0x360 [sg]
[<ffffffffa0025feb>] sg_write+0x13b/0x450 [sg]
[<ffffffff8032ec91>] vfs_write+0xd1/0x1b0
[<ffffffff8032ee54>] SyS_write+0x54/0xc0
[<ffffffff80689932>] system_call_fastpath+0x12/0x17

tj: updated description.

Fixes: 12cb5ce101ab ("libata: use blk taging")
Reported-and-tested-by: Tony Battersby <tonyb@cybernetics.com>
Signed-off-by: Shaohua Li <shli@fb.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

libsas: remove task_collector mode

The task_collector mode (or "latency_injector", (C) Dan Willians) is an
optional I/O path in libsas that queues up scsi commands instead of
directly sending it to the hardware. It generall increases latencies
to in the optiomal case slightly reduce mmio traffic to the hardware.

Only the obsolete aic94xx driver and the mvsas driver allowed to use
it without recompiling the kernel, and most drivers didn't support it
at all.

Remove the giant blob of code to allow better optimizations for scsi-mq
in the future.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Acked-by: Dan Williams <dan.j.williams@intel.com>

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>

libata, libsas: kill pm_result and related cleanup

Tejun says:
"At least for libata, worrying about suspend/resume failures don't make
whole lot of sense. If suspend failed, just proceed with suspend. If
the device can't be woken up afterwards, that's that. There isn't
anything we could have done differently anyway. The same for resume, if
spinup fails, the device is dud and the following commands will invoke
EH actions and will eventually fail. Again, there really isn't any
*choice* to make. Just making sure the errors are handled gracefully
(ie. don't crash) and the following commands are handled correctly
should be enough."

The only libata user that actually cares about the result from a suspend
operation is libsas. However, it only cares about whether queuing a new
operation collides with an in-flight one. All libsas does with the
error is retry, but we can just let libata wait for the previous
operation before continuing.

Other cleanups include:
1/ Unifying all ata port pm operations on an ata_port_pm_ prefix
2/ Marking all ata port pm helper routines as returning void, only
ata_port_pm_ entry points need to fake a 0 return value.
3/ Killing ata_port_{suspend|resume}_common() in favor of calling
ata_port_request_pm() directly
4/ Killing the wrappers that just do a to_ata_port() conversion
5/ Clearly marking the entry points that do async operations with an
_async suffix.

Reference: http://marc.info/?l=linux-scsi&m=138995409532286&w=2

Cc: Phillip Susi <psusi@ubuntu.com>
Cc: Alan Stern <stern@rowland.harvard.edu>
Suggested-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Todd Brandt <todd.e.brandt@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Tejun Heo <tj@kernel.org>

[SCSI] libsas: fix usage of ata_tf_to_fis

Since commit 110dd8f19df5 "[SCSI] libsas: fix scr_read/write users and
update the libata documentation" we have been passing pmp=1 and is_cmd=0
to ata_tf_to_fis(). Praveen reports that eSATA attached drives do not
discover correctly. His investigation found that the BIOS was passing
pmp=0 while Linux was passing pmp=1 and failing to discover the drives.
Update libsas to follow the libata example of pulling the pmp setting
from the ata_link and correct is_cmd to be 1 since all tf's submitted
through ->qc_issue are commands. Presumably libsas lldds do not care
about is_cmd as they have sideband mechanisms to perform link
management.

http://marc.info/?l=linux-scsi&m=138179681726990

[jejb: checkpatch fix]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reported-by: Praveen Murali <pmurali@logicube.com>
Tested-by: Praveen Murali <pmurali@logicube.com>
Cc: stable@vger.kernel.org
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] libsas, ipr: cleanup ata_host flags initialization via ata_host_init

libsas and ipr pass flags to ata_host_init that are meant for the port.

ata_host flags:
ATA_HOST_SIMPLEX = (1 << 0), /* Host is simplex, one DMA channel per host only */
ATA_HOST_STARTED = (1 << 1), /* Host started */
ATA_HOST_PARALLEL_SCAN = (1 << 2), /* Ports on this host can be scanned in parallel */
ATA_HOST_IGNORE_ATA = (1 << 3), /* Ignore ATA devices on this host. */

flags passed by libsas:
ATA_FLAG_SATA = (1 << 1),
ATA_FLAG_PIO_DMA = (1 << 7), /* PIO cmds via DMA */
ATA_FLAG_NCQ = (1 << 10), /* host supports NCQ */

The only one that aliases is ATA_HOST_STARTED which is a 'don't care' in
the libsas and ipr cases since ata_hosts from these sources are not
registered with libata.

Reported-by: Hannes Reinecke <hare@suse.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Brian King <brking@us.ibm.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: suspend / resume support

libsas power management routines to suspend and recover the sas domain
based on a model where the lldd is allowed and expected to be
"forgetful".

sas_suspend_ha - disable event processing allowing the lldd to take down
links without concern for causing hotplug events.
Regardless of whether the lldd actually posts link down
messages libsas notifies the lldd that all
domain_devices are gone.

sas_prep_resume_ha - on the way back up before the lldd starts link
training clean out any spurious events that were
generated on the way down, and re-enable event
processing

sas_resume_ha - after the lldd has started and decided that all phys
have posted link-up events this routine is called to let
libsas start it's own timeout of any phys that did not
resume. After the timeout an lldd can cancel the
phy teardown by posting a link-up event.

Storage for ex_change_count (u16) and phy_change_count (u8) are changed
to int so they can be set to -1 to indicate 'invalidated'.

Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Tested-by: Maciej Patelczyk <maciej.patelczyk@intel.com>
Acked-by: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] async: introduce 'async_domain' type

This is in preparation for teaching async_synchronize_full() to sync all
pending async work, and not just on the async_running domain. This
conversion is functionally equivalent, just embedding the existing list
in a new async_domain type.

The .registered attribute is used in a later patch to distinguish
between domains that want to be flushed by async_synchronize_full()
versus those that only expect async_synchronize_{full|cookie}_domain to
be used for flushing.

[jejb: add async.h to scsi_priv.h for struct async_domain]
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Arjan van de Ven <arjan@linux.intel.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Tested-by: Eldad Zack <eldad@fogrefinery.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: cleanup spurious calls to scsi_schedule_eh

eh is woken up automatically by the presence of failed commands,
scsi_schedule_eh is reserved for cases where there are no failed
commands. This guarantees that host_eh_sceduled is only incremented
when an explicit eh request is made.

Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
[fixed spurious delete of sas_ata_task_abort]
Signed-off-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>

[SCSI] libata, libsas: introduce sched_eh and end_eh port ops

When managing shost->host_eh_scheduled libata assumes that there is a
1:1 shost-to-ata_port relationship. libsas creates a 1:N relationship
so it needs to manage host_eh_scheduled cumulatively at the host level.
The sched_eh and end_eh port port ops allow libsas to track when domain
devices enter/leave the "eh-pending" state under ha->lock (previously
named ha->state_lock, but it is no longer just a lock for ha->state
changes).

Since host_eh_scheduled indicates eh without backing commands pinning
the device it can be deallocated at any time. Move the taking of the
domain_device reference under the port_lock to guarantee that the
ata_port stays around for the duration of eh.

Reviewed-by: Jacek Danecki <jacek.danecki@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: fix taskfile corruption in sas_ata_qc_fill_rtf

fill_result_tf() grabs the taskfile flags from the originating qc which
sas_ata_qc_fill_rtf() promptly overwrites. The presence of an
ata_taskfile in the sata_device makes it tempting to just copy the full
contents in sas_ata_qc_fill_rtf(). However, libata really only wants
the fis contents and expects the other portions of the taskfile to not
be touched by ->qc_fill_rtf. To that end store a fis buffer in the
sata_device and use ata_tf_from_fis() like every other ->qc_fill_rtf()
implementation.

Cc: <stable@vger.kernel.org>
Reported-by: Praveen Murali <pmurali@logicube.com>
Tested-by: Praveen Murali <pmurali@logicube.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

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

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

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

BUG: unable to handle kernel paging request at 0000000000003b10
IP: [<ffffffffa0053d7e>] sas_ata_end_eh+0x12/0x5e [libsas]
...
[<ffffffffa004d1af>] sas_unregister_common_dev+0x78/0xc9 [libsas]
[<ffffffffa004d4d4>] sas_unregister_dev+0x4f/0xad [libsas]
[<ffffffffa004d5b1>] sas_unregister_domain_devices+0x7f/0xbf [libsas]
[<ffffffffa004c487>] sas_deform_port+0x61/0x1b8 [libsas]
[<ffffffffa004bed0>] sas_phye_loss_of_signal+0x29/0x2b [libsas]

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

Reported-by: Michal Kosciowski <michal.kosciowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: don't recover end devices attached to disabled phys

If userspace has decided to disable a phy the kernel should honor that
and not inadvertantly re-enable the phy via error recovery. This is
more straightforward in the sata case where link recovery (via
libata-eh) is separate from sas_task cancelling in libsas-eh. Teach
libsas to accept -ENODEV as a successful response from I_T_nexus_reset
('successful' in terms of not escalating further).

This is a more comprehensive fix then "libsas: don't recover 'gone'
devices in sas_ata_hard_reset()", as it is no longer sata-specific.

aic94xx does check the return value from sas_phy_reset() so if the phy
is disabled we proceed with clearing the I_T_nexus.

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

[SCSI] libsas: revert ata srst

libata issues follow up srsts when the controller has a hard time
recording the signature-fis after a reset, or if the link supports port
multipliers. libsas does not support port multipliers and no current
libsas lldds appear to need help retrieving the signature fis. Revert
it for now to remove confusion.

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

[SCSI] libsas: async ata scanning

libsas ata error handling is already async but this does not help the
scan case. Move initial link recovery out from under host->scan_mutex,
and delay synchronization with eh until after all port probe/recovery
work has been queued.

Device ordering is maintained with scan order by still calling
sas_rphy_add() in order of domain discovery.

Since we now scan the domain list when invoking libata-eh we need to be
careful to check for fully initialized ata ports.

Acked-by: Jack Wang <jack_wang@usish.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: restore scan order

ata devices are always scanned after ssp. Prior to the ata error
handling reworks libsas would tend to scan devices in ascending expander
phy order. Restore this ordering by deferring ssp discovery to a
DISCE_PROBE event, and keep the probe order consistent with the
discovery order, not the placement of sata devices.

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

[SCSI] libsas: let libata recover links that fail to transmit initial sig-fis

libsas fails to discover all sata devices in the domain. If a device fails
negotiation and does not transmit a signature fis the link needs recovery.
libata already understands how to manage slow to come up links, so treat these
conditions as ata device attach events for the purposes of creating an
ata_port. This allows libata to manage retrying link bring up.

Rediscovery is modified to be careful about checking changes in dev_type. It
looks like libsas leaks old devices if the sas address changes, but that's a
fix for another patch.

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>

[SCSI] libsas: improve debug statements

It's difficult to determine which domain_device is triggering error recovery,
so convert messages like:

sas: ex 5001b4da000e703f phy08:T attached: 5001b4da000e7028
sas: ex 5001b4da000e703f phy09:T attached: 5001b4da000e7029
...
ata7: sas eh calling libata port error handler
ata8: sas eh calling libata port error handler

...into:

sas: ex 5001517e85cfefff phy05:T:9 attached: 5001517e85cfefe5 (stp)
sas: ex 5001517e3b0af0bf phy11:T:8 attached: 5001517e3b0af0ab (stp)
...
sas: ata7: end_device-21:1: dev error handler
sas: ata8: end_device-20:0:5: dev error handler

which shows attached link rate, device type, and associates a
domain_device with its ata_port id to correlate messages emitted from
libata-eh.

As Doug notes, we can also take the opportunity to clarify expander phy
routing capabilities.

[dgilbert@interlog.com: clarify table2table with 'U']
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: fix mixed topology recovery

If we have a domain with sas and sata devices there may still be sas
recovery actions to take after peeling off the commands to send to
libata.

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

[SCSI] libsas: close scsi_remove_target() vs libata-eh race

ata_port lifetime in libata follows the host. In libsas it follows the
scsi_target. Once scsi_remove_device() has caused all commands to be
completed it allows scsi_remove_target() to immediately proceed to
freeing the ata_port causing bug reports like:

[ 848.393333] BUG: spinlock bad magic on CPU#4, kworker/u:2/5107
[ 848.400262] general protection fault: 0000 [#1] SMP
[ 848.406244] CPU 4
[ 848.408310] Modules linked in: nls_utf8 ipv6 uinput i2c_i801 i2c_core iTCO_wdt iTCO_vendor_support ioatdma dca sg sd_mod sr_mod cdrom ahci libahci isci libsas libata scsi_transport_sas [last unloaded: scsi_wait_scan]
[ 848.432060]
[ 848.434137] Pid: 5107, comm: kworker/u:2 Not tainted 3.2.0-isci+ #8 Intel Corporation S2600CP/S2600CP
[ 848.445310] RIP: 0010:[<ffffffff8126a68c>] [<ffffffff8126a68c>] spin_dump+0x5e/0x8c
[ 848.454787] RSP: 0018:ffff8807f868dca0 EFLAGS: 00010002
[ 848.461137] RAX: 0000000000000048 RBX: ffff8807fe86a630 RCX: ffffffff817d0be0
[ 848.469520] RDX: 0000000000000000 RSI: ffffffff814af1cf RDI: 0000000000000002
[ 848.477959] RBP: ffff8807f868dcb0 R08: 00000000ffffffff R09: 000000006b6b6b6b
[ 848.486327] R10: 000000000003fb8c R11: ffffffff81a19448 R12: 6b6b6b6b6b6b6b6b
[ 848.494699] R13: ffff8808027dc520 R14: 0000000000000000 R15: 000000000000001e
[ 848.503067] FS: 0000000000000000(0000) GS:ffff88083fd00000(0000) knlGS:0000000000000000
[ 848.512899] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 848.519710] CR2: 00007ff77d001000 CR3: 00000007f7a5d000 CR4: 00000000000406e0
[ 848.528072] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 848.536446] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 848.544831] Process kworker/u:2 (pid: 5107, threadinfo ffff8807f868c000, task ffff8807ff348000)
[ 848.555327] Stack:
[ 848.557959] ffff8807fe86a630 ffff8807fe86a630 ffff8807f868dcd0 ffffffff8126a6e0
[ 848.567072] ffffffff817c142f ffff8807fe86a630 ffff8807f868dcf0 ffffffff8126a703
[ 848.576190] ffff8808027dc520 0000000000000286 ffff8807f868dd10 ffffffff814af1bb
[ 848.585281] Call Trace:
[ 848.588409] [<ffffffff8126a6e0>] spin_bug+0x26/0x28
[ 848.594357] [<ffffffff8126a703>] do_raw_spin_unlock+0x21/0x88
[ 848.601283] [<ffffffff814af1bb>] _raw_spin_unlock_irqrestore+0x2c/0x65
[ 848.609089] [<ffffffffa001c103>] ata_scsi_port_error_handler+0x548/0x557 [libata]
[ 848.618331] [<ffffffff81061813>] ? async_schedule+0x17/0x17
[ 848.625060] [<ffffffffa004f30f>] async_sas_ata_eh+0x45/0x69 [libsas]
[ 848.632655] [<ffffffff810618aa>] async_run_entry_fn+0x97/0x125
[ 848.639670] [<ffffffff81057439>] process_one_work+0x207/0x38d
[ 848.646577] [<ffffffff8105738c>] ? process_one_work+0x15a/0x38d
[ 848.653681] [<ffffffff810576f7>] worker_thread+0x138/0x21c
[ 848.660305] [<ffffffff810575bf>] ? process_one_work+0x38d/0x38d
[ 848.667493] [<ffffffff8105b098>] kthread+0x9d/0xa5
[ 848.673382] [<ffffffff8106e1bd>] ? trace_hardirqs_on_caller+0x12f/0x166
[ 848.681304] [<ffffffff814b7704>] kernel_thread_helper+0x4/0x10
[ 848.688324] [<ffffffff814af534>] ? retint_restore_args+0x13/0x13
[ 848.695530] [<ffffffff8105affb>] ? __init_kthread_worker+0x5b/0x5b
[ 848.702929] [<ffffffff814b7700>] ? gs_change+0x13/0x13
[ 848.709155] Code: 00 00 48 8d 88 38 04 00 00 44 8b 80 84 02 00 00 31 c0 e8 cf 1b 24 00 41 83 c8 ff 44 8b 4b 08 48 c7 c1 e0 0b 7d 81 4d 85 e4 74 10 <45> 8b 84 24 84 02 00 00 49 8d 8c 24 38 04 00 00 8b 53 04 48 89
[ 848.732467] RIP [<ffffffff8126a68c>] spin_dump+0x5e/0x8c
[ 848.738905] RSP <ffff8807f868dca0>
[ 848.743743] ---[ end trace 143161646eee8caa ]---

...so arrange for the ata_port to have the same end of life as the domain
device.

Reported-by: Marcin Tomczak <marcin.tomczak@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
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: don't recover 'gone' devices in sas_ata_hard_reset()

The commands that timeout when a disk is forcibly removed may trigger
libata to attempt recovery of the device. If libsas has decided to
remove the device don't permit ata to continue to issue resets to its
last known phy.

The primary motivation for this patch is hotplug testing by writing 0 to
/sys/class/sas_phy/phyX/enable. Without this check this test leads to
libata issuing a reset and re-enabling the device that wants to be torn
down.

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

[SCSI] libsas: fix sas_find_local_phy(), take phy references

In the direct-attached case this routine returns the phy on which this
device was first discovered. Which is broken if we want to support
wide-targets, as this phy reference can become stale even though the
port is still active.

In the expander-attached case this routine tries to lookup the phy by
scanning the attached sas addresses of the parent expander, and BUG_ONs
if it can't find it. However since eh and the libsas workqueue run
independently we can still be attempting device recovery via eh after
libsas has recorded the device as detached. This is even easier to hit
now that eh is blocked while device domain rediscovery takes place, and
that libata is fed more timed out commands increasing the chances that
it will try to recover the ata device.

Arrange for dev->phy to always point to a last known good phy, it may be
stale after the port is torn down, but it will catch up for wide port
reconfigurations, and never be NULL.

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

[SCSI] libsas: poll for ata device readiness after reset

Use ata_wait_after_reset() to poll for link recovery after a reset.
This combined with sas_ha->eh_mutex prevents expander rediscovery from
probing phys in an intermediate state. Local discovery does not have a
mechanism to filter link status changes during this timeout, so it
remains the responsibility of lldds to prevent premature port teardown.
Although once all lldd's support ->lldd_ata_check_ready() that could be
used as a gate to local port teardown.

The signature fis is re-transmitted when the link comes back so we
should be revalidating the ata device class, but that is left to a future
patch.

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

[SCSI] libsas: async ata-eh

Once sas_ata_hard_reset() starts honoring the 'deadline' parameter a
pathological configuration could take 25 seconds per ata device
(serialized) to recover. Run per-port recoveries in parallel.

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

[SCSI] libsas: execute transport link resets with libata-eh via host workqueue

Link resets leave ata affiliations intact, so arrange for libsas to make
an effort to avoid dropping the device due to a slow-to-recover link.
Towards this end carry out reset in the host workqueue so that it can
check for ata devices and kick the reset request to libata. Hard
resets, in contrast, bypass libata since they are meant for associating
an ata device with another initiator in the domain (tears down
affiliations).

Need to add a new transport_sas_phy_reset() since the current
sas_phy_reset() is a utility function to libsas lldds. They are not
prepared for it to loop back into eh.

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

[SCSI] libsas: use libata-eh-reset for sata rediscovery fis transmit failures

Since sata devices can take several seconds to recover the link on reset
the 0.5 seconds that libsas currently waits may not be enough. Instead
if we are rediscovering a phy that was previously attached to a sata
device let libata handle any resets to encourage the device to transmit
the initial fis.

Once sas_ata_hard_reset() and lldds learn how to honor 'deadline' libsas
should stop encountering phys in an intermediate state, until then this
will loop until the fis is transmitted or ->attached_sas_addr gets
cleared, but in the more likely initial discovery case we keep existing
behavior.

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

[SCSI] libsas: defer SAS_TASK_NEED_DEV_RESET commands to libata

lldds use the SAS_TASK_NEED_DEV_RESET interface to request that eh
perform a reset. In the sata device case defer the commands that
triggered the reset to libata-eh context so it can perform its pre and
post reset management.

In the sas_ata_post_internal() case the reset request is falling on deaf
ears as the sas_task is immediately destroyed without any reset action.
Since it is currently a nop, and likely superfluous given the conversion
to new-style libata-eh, just drop the request.

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

[SCSI] libsas: fix timeout vs completion race

Until we have told the lldd to forget a task a timed out operation can
return from the hardware at any time. Since completion frees the task
we need to make sure that no tasks run their normal completion handler
once eh has decided to manage the task. Similar to
ata_scsi_cmd_error_handler() freeze completions to let eh judge the
outcome of the race.

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

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

[SCSI] libsas: close error handling vs sas_ata_task_done() race

Since sas_ata does not implement ->freeze(), completions for scmds and
internal commands can still arrive concurrent with
ata_scsi_cmd_error_handler() and sas_ata_post_internal() respectively.
By the time either of those is called libata has committed to completing
the qc, and the ATA_PFLAG_FROZEN flag tells sas_ata_task_done() it has
lost the race.

In the sas_ata_post_internal() case we take on the additional
responsibility of freeing the sas_task to close the race with
sas_ata_task_done() freeing the the task while sas_ata_post_internal()
is in the process of invoking ->lldd_abort_task().

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

[SCSI] libsas: kill invocation of scsi_eh_finish_cmd from sas_ata_task_done

Prior to the conversion to the new-style libata-eh sas_ata_task_done()
may have been the last opportunity to clean up the scmd, but now
libata-eh explicitly handles this case. It also races against sas-eh.
If a lldd completes a task after SAS_TASK_STATE_ABORTED is set it could
trigger a spurious decrement of shost->host_failed. Current lldds have
the band-aid of checking SAS_TASK_STATE_ABORTED before calling
->task_done(), but better to just let the scmds escalate to libata for
race free cleanup.

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

[SCSI] libsas: use ->set_dmamode to notify lldds of NCQ parameters

sas_discover_sata() notifies lldds of sata devices twice. Once to allow
the 'identify' to be sent, and a second time to allow aic94xx (the only
libsas driver that cares about sata_dev.identify) to setup NCQ
parameters before the device becomes known to the midlayer. Replace
this double notification and intervening 'identify' with an explicit
->lldd_ata_set_dmamode notification. With this change all ata internal
commands are issued by libata, so we no longer need sas_issue_ata_cmd().

The data from the identify command only needs to be cached in one
location so ata_device.id replaces domain_device.sata_dev.identify.

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

[SCSI] libsas: prevent domain rediscovery competing with ata error handling

libata error handling provides for a timeout for link recovery. libsas
must not rescan for previously known devices in this interval otherwise
it may remove a device that is simply waiting for its link to recover.
Let libata-eh make the determination of when the link is stable and
prevent libsas (host workqueue) from taking action while this
determination is pending.

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

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

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

[SCSI] libsas: convert dev->gone to flags

In preparation for adding tracking of another device state "destroy".

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] libsas: remove unused ata_task_resp fields

Commit 1e34c838 "[SCSI] libsas: remove spurious sata control register
read/write" removed the routines to fake the presence of the sata
control registers, now remove the unused data structure fields to kill
any remaining confusion.

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>

[SCSI] libsas: Add option for SATA soft reset

This allows a libsas driver to optionally provide a soft reset handler
for libata to drive. The isci driver allows software to control the
assertion/deassertion of SRST.

[jejb: checkpatch.pl fixes]
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] libsas: fix SATA NCQ error

Current version of libsas can not handle SATA NCQ error.
This patch handle SATA NCQ error as AHCI do.

Signed-off-by: Xiangliang Yu <yuxiangl@marvell.com>
Signed-off-by: James Bottomley <jbottomley@parallels.com>

[SCSI] libsas: fix ata list corruption issue

I think this stems from a misunderstanding of how the ata error handler
works. ata_scsi_cmd_error_handler() gets called with a passed in list
of commands to handle. However, that list may still not be empty when
it exits. The command ata_scsi_port_error_handler() must be called
(which takes no list) before the list will be completely emptied. This
bites the sas error handler because the two are called from different
functions and the original list has gone out of scope before
ata_scsi_port_error_handler() is called. leading to some commands
dangling on bare stack, which is a potential memory corruption issue.
Fix this by manually deleting all outstanding commands from the on-stack
list before it goes out of scope.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

libata: remove ATA_FLAG_NO_LEGACY

All checks of ATA_FLAG_NO_LEGACY have been removed by the commits
c791c30670ea61f19eec390124128bf278e854fe ([libata] minor PCI IDE probe
fixes and cleanups) and f0d36efdc624beb3d9e29b9ab9e9537bf0f25d5b (libata:
update libata core layer to use devres), so I think it's time to finally
get rid of this flag...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: remove ATA_FLAG_MMIO

Commit 0d5ff566779f894ca9937231a181eb31e4adff0e (libata: convert to iomap)
removed all checks of ATA_FLAG_MMIO but neglected to remove the flag itself.
Do it now, at last...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: remove ATA_FLAG_{SRST|SATA_RESET}

These flags are marked as obsolete and the checks for them have been removed
by commit 294440887b32c58d220fb54b73b7a58079b78f20 (libata-sff: kill unused
ata_bus_reset()), so I think it's time to finally get rid of them...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

ipr/sas_ata: use mode mask macros from <linux/ata.h>

Commit 14bdef982caeda19afe34010482867c18217c641 ([libata] convert drivers to
use ata.h mode mask defines) didn't convert these two libata driver outside
drivers/ata/...

Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libsas: convert to libata new error handler

The conversion is quite complex given that the libata new error
handler has to be hooked into the current libsas timeout and error
handling. The way this is done is to process all the failed commands
via libsas first, but if they have no underlying sas task (and they're
on a sata device) assume they are destined for the libata error
handler and send them accordingly.

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

Signed-off-by: James Bottomley <James.Bottomley@suse.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

[SCSI] libsas: convert to libata new error handler

The conversion is quite complex given that the libata new error
handler has to be hooked into the current libsas timeout and error
handling. The way this is done is to process all the failed commands
via libsas first, but if they have no underlying sas task (and they're
on a sata device) assume they are destined for the libata error
handler and send them accordingly.

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

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] libsas: remove spurious sata control register read/write

Originally, libata required the illusion that it could access the sata
control register. Now, however, it can run perfectly well without
them, so remove the dummy routines from libsas which tried to emulate
them (but only ended up causing confusion).

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] libsas: fix ATAPI check condition termination

ATAPI check condition needs to be treated the same as a success or
protocol return. The register returns from the PACKET command are all
correctly positioned in the device to host register FIS and so we
should collect them properly. Right at the moment this doesn't matter
because libata sends a request sense always for ATAPI errors, but if
it ever checked the registers, we should have the correct contents
just in case.

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] libsas: Don't issue commands to devices that have been hot-removed

sd will get hung up issuing commands to flush write cache if a SAS
device behind the expander is unplugged without warning. Change libsas
to reject commands to domain devices that have already gone away.

[maciej.trela@intel.com: removed setting ->gone in sas_deform_port() to
permit sync cache commands at module removal]

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Tested-by: Haipao Fan <haipao.fan@intel.com>
Signed-off-by: Maciej Trela <maciej.trela@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] libsas: fix NCQ mixing with non-NCQ

Some cards (like mvsas) have issue troubles if non-NCQ commands are
mixed with NCQ ones. Fix this by using the libata default NCQ check
routine which waits until all NCQ commands are complete before issuing
a non-NCQ one. The impact to cards (like aic94xx) which don't need
this logic should be minimal

Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] Unify SAM_ and SAM_STAT_ macros

We have two separate definitions for identical constants with nearly the
same name. One comes from the generic headers in scsi.h; the other is
an enum in libsas.h ... it's causing confusion about which one is
correct (fortunately they both are).

Fix this by eliminating the libsas.h duplicate

Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] libsas: fix deref before check in commit 70b25f890ce

commit 70b25f890ce9f0520c64075ce9225a5b020a513e
Author: Tejun Heo <tj@kernel.org>
Date: Thu Apr 15 09:00:08 2010 +0900

[SCSI] fix locking around blk_abort_request()

Introduced a reference before check problem, fix this by moving the
lock shorthand code to be right at the point of actual use.

Reported-by: Dan Carpenter <error27@gmail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Cc: Stable Tree <stable@kernel.org>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

[SCSI] fix locking around blk_abort_request()

blk_abort_request() expects queue lock to be held by the caller.
Grab it before calling the function.

Lack of this synchronization led to infinite loop on corrupt
q->timeout_list.

Signed-off-by: Tejun Heo <tj@kernel.org>
Cc: stable@kernel.org
Signed-off-by: James Bottomley <James.Bottomley@suse.de>

include cleanup: Update gfp.h and slab.h includes to prepare for breaking implicit slab.h inclusion from percpu.h

percpu.h is included by sched.h and module.h and thus ends up being
included when building most .c files. percpu.h includes slab.h which
in turn includes gfp.h making everything defined by the two files
universally available and complicating inclusion dependencies.

percpu.h -> slab.h dependency is about to be removed. Prepare for
this change by updating users of gfp and slab facilities include those
headers directly instead of assuming availability. As this conversion
needs to touch large number of source files, the following script is
used as the basis of conversion.

http://userweb.kernel.org/~tj/misc/slabh-sweep.py

The script does the followings.

* Scan files for gfp and slab usages and update includes such that
only the necessary includes are there. ie. if only gfp is used,
gfp.h, if slab is used, slab.h.

* When the script inserts a new include, it looks at the include
blocks and try to put the new include such that its order conforms
to its surrounding. It's put in the include block which contains
core kernel includes, in the same order that the rest are ordered -
alphabetical, Christmas tree, rev-Xmas-tree or at the end if there
doesn't seem to be any matching order.

* If the script can't find a place to put a new include (mostly
because the file doesn't have fitting include block), it prints out
an error message indicating which .h file needs to be added to the
file.

The conversion was done in the following steps.

1. The initial automatic conversion of all .c files updated slightly
over 4000 files, deleting around 700 includes and adding ~480 gfp.h
and ~3000 slab.h inclusions. The script emitted errors for ~400
files.

2. Each error was manually checked. Some didn't need the inclusion,
some needed manual addition while adding it to implementation .h or
embedding .c file was more appropriate for others. This step added
inclusions to around 150 files.

3. The script was run again and the output was compared to the edits
from #2 to make sure no file was left behind.

4. Several build tests were done and a couple of problems were fixed.
e.g. lib/decompress_*.c used malloc/free() wrappers around slab
APIs requiring slab.h to be added manually.

5. The script was run on all .h files but without automatically
editing them as sprinkling gfp.h and slab.h inclusions around .h
files could easily lead to inclusion dependency hell. Most gfp.h
inclusion directives were ignored as stuff from gfp.h was usually
wildly available and often used in preprocessor macros. Each
slab.h inclusion directive was examined and added manually as
necessary.

6. percpu.h was updated not to include slab.h.

7. Build test were done on the following configurations and failures
were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my
distributed build env didn't work with gcov compiles) and a few
more options had to be turned off depending on archs to make things
build (like ipr on powerpc/64 which failed due to missing writeq).

* x86 and x86_64 UP and SMP allmodconfig and a custom test config.
* powerpc and powerpc64 SMP allmodconfig
* sparc and sparc64 SMP allmodconfig
* ia64 SMP allmodconfig
* s390 SMP allmodconfig
* alpha SMP allmodconfig
* um on x86_64 SMP allmodconfig

8. percpu.h modifications were reverted so that it could be applied as
a separate patch and serve as bisection point.

Given the fact that I had only a couple of failures from tests on step
6, I'm fairly confident about the coverage of this conversion patch.
If there is a breakage, it's likely to be something in one of the arch
headers which should be easily discoverable easily on most builds of
the specific arch.

Signed-off-by: Tejun Heo <tj@kernel.org>
Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>

block: unify request timeout handling

Right now SCSI and others do their own command timeout handling.
Move those bits to the block layer.

Instead of having a timer per command, we try to be a bit more clever
and simply have one per-queue. This avoids the overhead of having to
tear down and setup a timer for each command, so it will result in a lot
less timer fiddling.

Signed-off-by: Mike Anderson <andmike@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

libata: make SCR access ops per-link

Logically, SCR access ops should take @link; however, there was no
compelling reason to convert all SCR access ops when adding @link
abstraction as there's one-to-one mapping between a port and a non-PMP
link. However, that assumption won't hold anymore with the scheduled
addition of slave link.

Make SCR access ops per-link.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

[SCSI] replace __FUNCTION__ with __func__

[jejb: fixed up a ton of missed conversions.

All of you are on notice this has happened, driver trees will now
need to be rebased]

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Cc: SCSI List <linux-scsi@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

libata: kill ata_noop_dev_select()

Now that SFF assumptions are separated out from non-SFF reset
sequence, port_ops->sff_dev_select() is no longer necessary for
non-SFF controllers. Kill ata_noop_dev_select() and ->sff_dev_select
initialization from base and other non-SFF port_ops.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: remove check_status from non-SFF drivers

Now that all SFF stuff is separated out of core layer, core layer
doesn't call ops->[alt_]check_status(). In fact, no one calls them
for non-SFF drivers anymore. Kill them.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: replace tf_read with qc_fill_rtf for non-SFF drivers

Now that all SFF stuff is separated out of core layer, core layer
doesn't call ops->tf_read directly. It gets called only via
ops->qc_fill_rtf() for non-SFF drivers. This patch directly
implements private ops->qc_fill_rtf() for non-SFF controllers and kill
ops->tf_read().

This is much cleaner for non-SFF controllers as some of them have to
cache SFF register values in private data structure and report the
cached values via ops->tf_read(). Also, ops->tf_read() gets nasty for
controllers which don't have clear notion of TF registers when
operation is not in progress.

As this change makes default ops->qc_fill_rtf unnecessary, move
ata_sff_qc_fill_rtf() form ata_base_port_ops to ata_sff_port_ops where
it belongs.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: add qc_fill_rtf port operation

On command completion, ata_qc_complete() directly called ops->tf_read
to fill qc->result_tf. This patch adds ops->qc_fill_rtf to replace
hardcoded ops->tf_read usage.

ata_sff_qc_fill_rtf() which uses ops->tf_read to fill result_tf is
implemented and set in ata_base_port_ops and other ops tables which
don't inherit from ata_base_port_ops, so this patch doesn't introduce
any behavior change.

ops->qc_fill_rtf() is similar to ops->sff_tf_read() but can only be
called when a command finishes. As some non-SFF controllers don't
have TF registers defined unless they're associated with in-flight
commands, this limited operation makes life easier for those drivers
and help lifting SFF assumptions from libata core layer.

Signed-off-by: Tejun Heo <htejun@gmail.com>

libata: rename SFF port ops

Add sff_ prefix to SFF specific port ops.

This rename is in preparation of separating SFF support out of libata
core layer. This patch strictly renames ops and doesn't introduce any
behavior difference.

Signed-off-by: Tejun Heo <htejun@gmail.com>

[SCSI] libsas: fix endianness bug in sas_ata

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] libsas: use the supplied address for SATA devices rather than changing it

Once the phy reset is plumbed in properly, SATA error handling fails
nastily because we change the port attached_sas_address using the WWN
field of the IDENTIFY message. This is a nice thing to do in theory,
but it really destroys hotplug because any event on the port causes an
automatic mismatch between the sas_address the phy just picked up and
the one we propagate into the port. However ugly they are, we have to
stick with the sas addresses made up by the phys and expanders.

Also does a few cosmetic changes to the way port printing is done to
make it clearer how a port is formed.

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

libata: eliminate the home grown dma padding in favour of

that provided by the block layer

ATA requires that all DMA transfers begin and end on word boundaries.
Because of this, a large amount of machinery grew up in ide to adjust
scatterlists on this basis. However, as of 2.5, the block layer has a
dma_alignment variable which ensures both the beginning and length of a
DMA transfer are aligned on the dma_alignment boundary. Although the
block layer does adjust the beginning of the transfer to ensure this
happens, it doesn't actually adjust the length, it merely makes sure
that space is allocated for transfers beyond the declared length. The
upshot of this is that scatterlists may be padded to any size between
the actual length and the length adjusted to the dma_alignment safely
knowing that memory is allocated in this region.

Right at the moment, SCSI takes the default dma_aligment which is on a
512 byte boundary. Note that this aligment only applies to transfers
coming in from user space. However, since all kernel allocations are
automatically aligned on a minimum of 32 byte boundaries, it is safe to
adjust them in this manner as well.

tj: * Adjusting sg after padding is done in block layer. Make libata
set queue alignment correctly for ATAPI devices and drop broken
sg mangling from ata_sg_setup().
* Use request->raw_data_len for ATAPI transfer chunk size.
* Killed qc->raw_nbytes.
* Separated out killing qc->n_iter.

Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

libata: convert to chained sg

libata used private sg iterator to handle padding sg. Now that sg can
be chained, padding can be handled using standard sg ops. Convert to
chained sg.

* s/qc->__sg/qc->sg/

* s/qc->pad_sgent/qc->extra_sg[]/. Because chaining consumes one sg
entry. There need to be two extra sg entries. The renaming is also
for future addition of other extra sg entries.

* Padding setup is moved into ata_sg_setup_extra() which is organized
in a way that future addition of other extra sg entries is easy.

* qc->orig_n_elem is unused and removed.

* qc->n_elem now contains the number of sg entries that LLDs should
map. qc->mapped_n_elem is added to carry the original number of
mapped sgs for unmapping.

* The last sg of the original sg list is used to chain to extra sg
list. The original last sg is pointed to by qc->last_sg and the
content is stored in qc->saved_last_sg. It's restored during
ata_sg_clean().

* All sg walking code has been updated. Unnecessary assertions and
checks for conditions the core layer already guarantees are removed.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata: rename ATA_PROT_ATAPI_* to ATAPI_PROT_*

ATA_PROT_ATAPI_* are ugly and naming schemes between ATA_PROT_* and
ATA_PROT_ATAPI_* are inconsistent causing confusion. Rename them to
ATAPI_PROT_* and make them consistent with ATA counterpart.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

libata: implement protocol tests

Implement protocol tests - ata_is_atapi(), ata_is_nodata(),
ata_is_pio(), ata_is_dma(), ata_is_ncq() and ata_is_data() and use
them to replace is_atapi_taskfile() and hard coded protocol tests.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[SCSI] libsas: don't use made up error codes

This is bad for two reasons:

1. If they're returned to outside applications, no-one knows what
they mean.
2. Eventually they'll clash with the ever expanding standard error
codes.

The problem error code in question is ETASK. I've replaced this by
ECOMM (communications error on send) a network error code that seems to
most closely relay what ETASK meant.

Acked-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[libata] Remove ->port_disable() hook

It was always set to ata_port_disable(). Removed the hook, and replaced
the very few ap->ops->port_disable() callsites with direct calls to
ata_port_disable().

Signed-off-by: Jeff Garzik <jeff@garzik.org>

libata-link: introduce ata_link

Introduce ata_link. It abstracts PHY and sits between ata_port and
ata_device. This new level of abstraction is necessary to support
SATA Port Multiplier, which basically adds a bunch of links (PHYs) to
a ATA host port. Fields related to command execution, spd_limit and
EH are per-link and thus moved to ata_link.

This patch only defines the host link. Multiple link handling will be
added later. Also, a lot of ap->link derefences are added but many of
them will be removed as each part is converted to deal directly with
ata_link instead of ata_port.

This patch introduces no behavior change.

Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: James Bottomley <James.Bottomley@SteelEye.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>

[SCSI] libsas: Remove PCI dependencies

Eliminate unnecessary PCI dependencies in libsas. It should use generic
DMA and struct device like other subsystems.

Signed-off-by: Jeff Garzik <jeff@garzik.org>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] libsas: make ATA functions selectable by a config option

Not everyone wants libsas automatically to pull in libata. This patch
makes the behaviour configurable, so you can build libsas with or
without ATA support.

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

[SCSI] libsas: fix scr_read/write users and update the libata documentation

This fixes up the usage in libsas (which are easy to miss, since they're
only in the scsi-misc tree) ... and also corrects the documentation on
the point of what these two function pointers actually return.

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

[SCSI] sas_ata: Implement sas_task_abort for ATA devices

ATA devices need special handling for sas_task_abort. If the ATA command
came from SCSI, then we merely need to tell SCSI to abort the scsi_cmnd.
However, internal commands require a bit more work--we need to fill the qc
with the appropriate error status and complete the command, and eventually
post_internal will issue the actual ABORT TASK.

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

[SCSI] sas_ata: Assign sas_task to scsi_cmnd to enable EH for ATA devices

The SATL should connect the scsi_cmnd to the sas_task (despite the presence
of libata) so that requests to abort scsi_cmnds headed to the ATA device
can be processed by the EH and aborted correctly. The abort status should
still be propagated from sas -> ata -> scsi.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] libsas: Unknown STP devices should be reported to libata as unknown.

When libsas encounters a STP device whose protocol isn't recognized (i.e.
not ATA or ATAPI), we should set the ata_device's class to ATA_DEV_UNKNOWN
instead of ATA_DEV_ATA.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] libsas: Accept SAM_GOOD for ATAPI devices in sas_ata_task_done

A sas_task sent to an ATAPI devices returns SAM_GOOD if successful.
Therefore, we should treat this the same way we treat ATA commands
that succeed.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] sas_ata: Don't copy aic94xx's sactive to ata_port

Since the aic94xx sequencer assigns its own NCQ tags to ATA commands, it
no longer makes any sense to copy the sactive field in the STP response
to ata_port->sactive, as that will confuse libata. Also, libata seems
to be capable of managing sactive on its own.

The attached patch gets rid of one of the causes of the BUG messages in
ata_qc_new, and seems to work without problems on an IBM x206m.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] sas_ata: ata_post_internal should abort the sas_task

This patch adds a new field, lldd_task, to ata_queued_cmd so that libata
users such as libsas can associate some data with a qc. The particular
ambition with this patch is to associate a sas_task with a qc; that way,
if libata decides to timeout a command, we can come back (in
sas_ata_post_internal) and abort the sas task.

One question remains: Is it necessary to reset the phy on error, or will
the libata error handler take care of it? (Assuming that one is written,
of course.) This patch, as it is today, works well enough to clean
things up when an ATA device probe attempt fails halfway through the probe,
though I'm not sure this is always the right thing to do.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] sas_ata: sas_ata_qc_issue should return AC_ERR_*

The sas_ata_qc_issue function was incorrectly written to return error
codes such as -ENOMEM. Since libata OR's qc->err_mask with the
return value, It is necessary to make my code return one of the
AC_ERR_ codes instead. For now, use AC_ERR_SYSTEM because an error
here means that the OS couldn't send the command to the controller.

If anybody has a suggestion for a better AC_ERR_ code to use, please
suggest it.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] sas_ata: Satisfy libata qc function locking requirements

ata_qc_complete and ata_sas_queuecmd require that the port lock be held
when they are called. sas_ata doesn't do this, leading to BUG messages
about qc tags newly allocated qc tags already being in use. This patch
fixes the locking, which should clean up the rest of those messages.

So far I've tested this against an IBM x206m with two SATA disks with no
BUG messages and no other signs of things going wrong, and the machine
finally passed the pounder stress test.

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] Migrate libsas ATA code into a separate file

This is a respin of my earlier patch that migrates the ATA support code
into a separate file. For now, the controversial linking bits have
been removed per James Bottomley's request for a patch that contains
only the migration diffs, which means that libsas continues to require
libata. I intend to address that problem in a separate patch.

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

Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>