Currently we use DQ lock to protect delivery of DQ entry one by one.

To optimise to allow more than one slot to be built for a single DQ in
parallel, we need to remove the DQ lock when preparing slots, prior to
delivery.

To achieve this, we rearrange the slot build order to ensure that once
we allocate a slot for a task, we do cannot fail to deliver the task.

In this patch, we rearrange the slot building for SMP tasks to ensure
that sg mapping part (which can fail) happens before we allocate the
slot in the DQ.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

After the controller is reset, we currently may not honour the PHY max
linkrate set via sysfs, in that after a reset we always revert to max
linkrate of 12Gbps, ignoring the value set via sysfs.

This patch modifies to policy to set the programmed PHY linkrate,
honouring the max linkrate programmed via sysfs.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

We should only have the timer enabled after PHY up after controller
reset, so disable prior to reset.
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

It is possible to dereference a NULL-pointer in hisi_sas_abort_task() in
special scenario when the device has been removed.

If an SMP task times-out, it will call hisi_sas_abort_task() to
recover. And currently there is a check in hisi_sas_abort_task() to
avoid the situation of processing the abort for the removed device.

However we have an ordering problem, in that we may reference a task for
the removed device before checking if the device has been removed.

Fix this by only referencing the sas_dev after we know it is still
present.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When the host is frozen in SCSI EH state, at any point after the LLDD
sets SAS_TASK_STATE_DONE for the sas_task task state, libsas may free
the task; see sas_scsi_find_task().

This puts the LLDD in a difficult position, in that once it sets
SAS_TASK_STATE_DONE for the task state it should not reference the
sas_task again. But the LLDD needs will check the sas_task indirectly in
calling task->task_done()->sas_scsi_task_done() or sas_ata_task_done()
(to check if the host is frozen state actually).

And the LLDD cannot set SAS_TASK_STATE_DONE for the task state after
task->task_done() is called (as the sas_task is free'd at this point).

This situation would seem to be a problem made by libsas.

To work around, check in the LLDD whether the host is in frozen state to
ensure it is ok to call task->task_done() function. If in the frozen
state, we rely on SCSI EH and libsas to free the sas_task directly.

We do not do this for the following IO types:

 - SMP - they are managed in libsas directly, outside SCSI EH
 - Any internally originated IO, for similar reason
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If the SCSI host enters EH, any pending IO will be processed by SCSI
EH. However it is possible that SCSI EH will try to abort the IO and
also at the same time the IO completes in the driver. In this situation
there is a small chance of freeing the sas_task twice.

Then if another IO re-uses freed sas_task before the second time of
free'ing sas_task, it is possible to free incorrect sas_task.

To avoid this situation, add some checks to increase reliability.  The
sas_task task state flag SAS_TASK_STATE_ABORTED is used to mutually
protect the LLDD and libsas freeing the task.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch removes unneeded structure elements:

- hisi_sas_phy.dev_sas_addr: only ever written
	- Also remove associated function which writes it,
	  hisi_sas_init_add().

- hisi_sas_device.attached_phy: only ever written
	- Also remove code to set it in hisi_sas_dev_found()
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Reviewed-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently we check the fis->command value in 2 locations in
hisi_sas_get_ata_protocol() switch statement. Fix this by consolidating
the check for fis->command value to 1 location only.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This is a warning coming from Coccinelle, and need to use new interface
dma_zalloc_coherent() instead of dma_alloc_coherent()/memset().
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Delete timer for v1 and v3 hw when removing hisi_sas driver.
Signed-off-by: NXiang chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The patch does some code cleanup and fixes some small bugs:

- Correct return status of phy_up_v3_hw() and phy_bcast_v3_hw()
- Add static for function phy_get_max_linkrate_v3_hw()
- Change exception return status when no reset method
- Change magic value to ts->stat in slot_complete_vx_hw()
- Remove unnecessary check for dev_is_sata()
- Fix some issues of alignment and indents (Authored by Xiaofei Tan in
  another patch, but added here to be practical)
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

It is an implicit regulation that error code that function returned should
be negative. But hisi_sas_task_prep() doesn't follow this.  This may cause
problems in the upper layer code.

For example, in sas_expander.c of libsas, smp_execute_task_sg() may return
the number of bytes of underrun. It will be conflicted with the scenaio
lldd_execute_task() return an positive error code.

This patch change the return value from SAS_PHY_DOWN to -ECOMM in
hisi_sas_task_prep().
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The structure element hisi_sas_devices.running_req to count how many
commands are active is in effect only ever written in the code, so remove
it.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The current 110ms expiry time is not long enough for the internal abort
task.

The reason is that the internal abort task could be blocked in HW if the HW
is retrying to set up link. The internal abort task will be executed only
when the retry process finished.

The maximum time is 5s for the retry of setting up link. So, the timer
expire should be more than 5s. This patch increases it from 110ms to 6s.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In sysfs, there are two files about minimum linkrate, and also two files for
maximum linkrate. Take maximum linkrate example, maximum_linkrate_hw is
read-only and indicated by the register HARD_PHY_LINKRATE, and
maximum_linkrate is read-write and corresponding to the register
PROG_PHY_LINK_RATE.

But in the function phy_up_v*_hw(), we get *_linkrate value from
HARD_PHY_LINKRATE. It is not right. This patch is to fix this issue.

Unreferenced PHY-interrupt enum is also removed for v3 hw.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When device gone, NULL pointer can be accessed in free_device callback
if during SAS controller reset as we clear structure sas_dev prior.

Actually we can only set dev_type as SAS_PHY_UNUSED and not clear
structure sas_dev as all the members of structure sas_dev will be
re-initialized after device found.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch implements LED feature of directly attached disk for v2 hw.
As libsas has provided an interface lldd_write_gpio() for this feature,
we just need realise the interface following SPGIO API.

We use an CPLD to finish the hardware part of this feature, and the base
address of CPLD should be configured through ACPI or DT tables.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fixes the following sparse warning:

drivers/scsi/hisi_sas/hisi_sas_main.c:1691:25: warning:
 symbol 'host_attrs' was not declared. Should it be static?
Signed-off-by: NWei Yongjun <weiyongjun1@huawei.com>
Acked-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

According to ATA protocol, SET MAX commands belong to different frame
types. So judge features field of SET MAX commands to decide which
frame type they belongs to.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add a sysfs attr that LLDD can configure it for every host. We made an
example in hisi_sas. Other LLDDs using libsas can implement it if they
want.
Suggested-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJason 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>
Acked-by: John Garry <john.garry@huawei.com> #for hisi_sas part
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

For v3 hw SAS, it supports configuring power state from D0 to D3 for entering
Low Power status and power state from D3 to D0 for quit Low Power status.

When power state from D0 to D3, HW will send FLR to clear the registers of
ECAM and BAR space, and when power state from D3 to D0, it will clear the
registers of ECAM space only.

So when suspend, need to do like controller reset (including disable
interrupts/DQ/PHY/BUS), and also release slots after FLR. When resume,
re-config the registers of BAR space.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In function sas_suspend_devices(), it requires callback lldd_port_deformed
callback to be implemented if lldd_port_deformed is implemented.

So add a stub for lldd_port_deformed.

Callback lldd_port_deformed was not required as the port deformation is done
elsewhere in the LLDD.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch fix SAS_QUEUE_FULL problem. The test situation is close port while
running IO.

In sas_eh_handle_sas_errors(), SCSI EH will free sas_task of the device if
lldd_I_T_nexus_reset() return TMF_RESP_FUNC_COMPLETE or -ENODEV.  But in our
SAS driver, we only free slots of the device when the return value is
TMF_RESP_FUNC_COMPLETE. So if the return value is -ENODEV, the slot resource
will not free any more.

As an solution, we should also free slots of the device in
lldd_I_T_nexus_reset() if the return value is -ENODEV.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

We should do internal abort dev before TMF_ABORT_TASK_SET and TMF_LU_RESET.
Because we may only have done internal abort for single IO in the earlier part
of SCSI EH process. Even the internal abort to the single IO, we also don't
know whether it is successful.

Besides, we should release slots of the device in hisi_sas_abort_task_set() if
the abort is successful.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Normally, hardware should ensure that internal abort timeout will never
happen. If happen, it would be an SoC failure. What's more, HW will not
process any other commands if an internal abort hasn't return CQ, and they
will time out also.

So, we should judge the result of internal abort in SCSI EH, if it is failed,
we should give up to do TMF/softreset and return failure to the upper layer
directly.

This patch do following things to achieve this:

1. When internal abort timeout happened, we set return value to -EIO in
   hisi_sas_internal_task_abort().

2. If prep_abort() is not support, let hisi_sas_internal_task_abort() return
   TMF_RESP_FUNC_FAILED.

3. If hisi_sas_internal_task_abort() return an negative number, it can be
   thought that it not executed properly or internal abort timeout. Then we
   won't do behind TMF or softreset, and return failure directly.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

We should do link reset of PHY when identify timeout or STP link timeout. They
are internal events of SOC and are notified to driver through interrupts of
CHL_INT2.

Besides, we should add an delay work to do link reset as it needs sleep. So,
this patch add an new PHY event HISI_PHYE_LINK_RESET for this.

Notes: v2 HW doesn't report the event of STP link timeout.  So, we only need
to handle event of identify timeout for v2 HW.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Use an general way to do delay work for a PHY. Then it will be easier to add
new delayed work for a PHY in future.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add some print at some places such as error info and cq of exception IO,
device found etc, and also adjust some log levels.

All this to assist debugging ability.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Sometimes it is required to know when the controller reset has completed and
also if it has completed successfully.  For such places, we call
hisi_sas_controller_reset() directly before. That may lead to multiple calls
to this function.

This patch create a per-reset structure which contains a completion structure
and status flag to know when the reset completes and also the status. It is
also in hisi_hba.wq to do reset work.

As all host reset works are done in hisi_hba.wq, we don't worry multiple calls
to hisi_sas_controller_reset().
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Do a couple of changes for when HISI_SAS_RESET_BIT is set for HBA:

 - Clearing ITCT is not necessary

 - Remove internal abort as it will fail during reset

Flag sas_dev->dev_type is kept as SAS_PHY_UNUSED.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch do following optimizations to host controller reset:

1. Unblock scsi requests before rescanning topology, as SCSI command need be
   used if new device is found during rescanning topology.

2. Remove drain_workqueue(hisi_hba->wq) and drain_workqueue(shost->work_q), as
   there is no need to ensure that all PHYs event are done before exiting host
   reset.

3. Improve message print level of host reset. Host reset is an important and
   very few occurrence event. We should know its progress even when not
   debugging.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Currently refreshing the PHY port id after reset is done in the rescan
topology function, which is quite late in the reset process. It could be moved
earlier in the process, as the port id can be refreshed once the PHYs become
ready.

In addition to this, we should set the hisi_sas_dev port id to 0xff (invalid
port id) if all PHYs of this port remain down for the same device.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In certain scenarios we may just want to clear the ITCT for a device, and not
free other resources like the SATA bitmap using in v2 hw.

To facilitate this, this patch relocates the code of clearing ITCT from
free_device() to a new hw interface clear_itct().  Then for some hw, we should
not realise free_device() if there's nothing left to do for it.

[mkp: typo]
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

For function dma_unmap_sg(), the <nents> parameter should be number of
elements in the scatterlist prior to the mapping, not after the mapping.

Fix this usage.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

It is required to initialize the dq spinlock before use, which was not being
done, so fix it. This issue can be detected when CONFIG_DEBUG_SPINLOCK is
enabled.
Signed-off-by: NXiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

With all callbacks converted, and the timer callback prototype
switched over, the TIMER_FUNC_TYPE cast is no longer needed,
so remove it. Conversion was done with the following scripts:

    perl -pi -e 's|\(TIMER_FUNC_TYPE\)||g' \
        $(git grep TIMER_FUNC_TYPE | cut -d: -f1 | sort -u)

    perl -pi -e 's|\(TIMER_DATA_TYPE\)||g' \
        $(git grep TIMER_DATA_TYPE | cut -d: -f1 | sort -u)

The now unused macros are also dropped from include/linux/timer.h.
Signed-off-by: NKees Cook <keescook@chromium.org>

In preparation for unconditionally passing the struct timer_list pointer to
all timer callbacks, switch to using the new timer_setup() and from_timer()
to pass the timer pointer explicitly. This requires adding a pointer to
hold the timer's target task, as there isn't a link back from slow_task.

Cc: John Garry <john.garry@huawei.com>
Cc: "James E.J. Bottomley" <jejb@linux.vnet.ibm.com>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Jack Wang <jinpu.wang@profitbricks.com>
Cc: lindar_liu@usish.com
Cc: Jens Axboe <axboe@fb.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Benjamin Block <bblock@linux.vnet.ibm.com>
Cc: Baoyou Xie <baoyou.xie@linaro.org>
Cc: Wei Yongjun <weiyongjun1@huawei.com>
Cc: linux-scsi@vger.kernel.org
Signed-off-by: NKees Cook <keescook@chromium.org>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Acked-by: John Garry <john.garry@huawei.com> # for hisi_sas part
Tested-by: John Garry <john.garry@huawei.com> # basic sanity test for hisi_sas
Reviewed-by: NJack Wang <jinpu.wang@profitbricks.com>

The CQ event is handled in tasklet context, and it could be delayed if
the system loading is high.

It is possible to run into some problems when executing a host reset
when cq_tasklet_vx_hw() is being executed.

So, prior to host reset, execute tasklet_kill() to ensure that all CQ
tasklets are complete.

Besides, as the function hisi_sas_wait_tasklets_done() is added to do
tasklet_kill(), this patch refactors some code where tasklet_kill() is
used.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Add init code of hisi_hba->rst_work for v3 hw. Because v3 hw also need
it to recover controller when some hw errors occurs.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The function hisi_sas_slot_task_free() is used to free the slot and do
tidy-up of LLDD resources. The LLDD generally should know the state of
a slot and decide when to free it, and it should only be done once.

For some scenarios, we really don't know the state, like when TMF
timeout. In this case, we check task->lldd_task before calling
hisi_sas_slot_task_free().

However, we may miss some scenarios when we should also check
task->lldd_task, and it is not SMP safe to check task->lldd_task as we
don't protect it within spin lock.

This patch is to fix this risk of freeing slot twice, as follows:

  1. Check task->lldd_task in the hisi_sas_slot_task_free(), and give
     up freeing of this time if task->lldd_task is NULL.

  2. Set slot->buf to NULL after it is freed.
Signed-off-by: NXiaofei Tan <tanxiaofei@huawei.com>
Signed-off-by: NJohn Garry <john.garry@huawei.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>