scsi: lpfc: Fix 'physical' typos

Fix misspellings of "physical".

Link: https://lore.kernel.org/r/20210126211248.2920028-1-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: megaraid_mbox: Fix spelling of 'allocated'

allocted -> allocated

Link: https://lore.kernel.org/r/20210126054908.45468-1-dingsenjie@163.com
Signed-off-by: dingsenjie <dingsenjie@yulong.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: qla2xxx: Simplify the calculation of variables

Fix the following coccicheck warnings:

./drivers/scsi/qla2xxx/qla_nvme.c:288:24-26: WARNING !A || A && B is
equivalent to !A || B.

Link: https://lore.kernel.org/r/1611650554-33019-1-git-send-email-abaci-bugfix@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Jiapeng Zhong <abaci-bugfix@linux.alibaba.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: message: fusion: Fix 'physical' typos

Fix misspellings of "physical".

Link: https://lore.kernel.org/r/20210126210328.2918631-1-helgaas@kernel.org
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: core: Change ASCQ for residual write

According to FCP-4 (9.4.2):

  If the command requested that data beyond the length specified by the
  FCP_DL field be transferred, then the device server shall set the
  FCP_RESID_OVER bit (see 9.5.8) to one in the FCP_RSP IU and:

  a) process the command normally except that data beyond the FCP_DL count
  shall not be requested or transferred;

  b) transfer no data and return CHECK CONDITION status with the sense key
  set to ILLEGAL REQUEST and the additional sense code set to INVALID FIELD
  IN COMMAND INFORMATION UNIT; or

  c) may transfer data and return CHECK CONDITION status with the sense key
  set to ABORTED COMMAND and the additional sense code set to INVALID FIELD
  IN COMMAND INFORMATION UNIT.

TCM follows b) and transfers no data for residual writes but returns
INVALID FIELD IN CDB instead of INVALID FIELD IN COMMAND INFORMATION UNIT.

Change the ASCQ to INVALID FIELD IN COMMAND INFORMATION UNIT to meet the
standard.

Link: https://lore.kernel.org/r/20201203082035.54566-4-a.kovaleva@yadro.com
Signed-off-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: core: Signal WRITE residuals

According to RFC 7143 11.4.5.2.:

  If SPDTL > EDTL for a task, iSCSI Overflow MUST be signaled in the SCSI
  Response PDU as specified in Section 11.4.5.1.  The Residual Count MUST
  be set to the numerical value of (SPDTL - EDTL).

  If SPDTL < EDTL for a task, iSCSI Underflow MUST be signaled in the SCSI
  Response PDU as specified in Section 11.4.5.1.  The Residual Count MUST
  be set to the numerical value of (EDTL - SPDTL).

libiscsi has residual write tests that check residual kind and residual
amount and all of them (Write10Residuals, Write12Residuals,
Write16Residuals) currently fail.

One of the reasons why they fail is because target completes write commands
with INVALID FIELD IN CDB before setting the Overflow/Underflow bit and
residual amount.

Set the Overflow/Underflow bit and the residual amount before failing a
write to comply with RFC 7143.

Link: https://lore.kernel.org/r/20201203082035.54566-3-a.kovaleva@yadro.com
Signed-off-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: core: Set residuals for 4Kn devices

TCM always fails SBC commands with residuals for 4Kn devices when the
command is processed by sbc_parse_cdb(). That prevents residual signalling
to the transport driver because residual kind and residual amount aren't
set. It also makes residual handling different from 512-byte formatted
devices - if there are residuals 512-byte LUN would proceed with command
execution while 4K-byte LUN would fail.

Link: https://lore.kernel.org/r/20201203082035.54566-2-a.kovaleva@yadro.com
Based-on: https://patchwork.kernel.org/project/target-devel/patch/20170523234854.21452-31-bart.vanassche@sandisk.com/
Based-on-patch-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Roman Bolshakov <r.bolshakov@yadro.com>
Signed-off-by: Konstantin Vinogradov <k.vinogradov@yadro.com>
Signed-off-by: Anastasia Kovaleva <a.kovaleva@yadro.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: hisi_sas: Add trace FIFO debugfs support

The controller provides trace FIFO DFX tool to assist link fault debugging
and link optimization. This tool can be helpful when debugging link faults
without SAS analyzers. Each PHY has an independent trace FIFO interface.

The user can configure the trace FIFO tool of one PHY by using the
following six interfaces:

signal_sel: select signal group applies to different scenarios.
  0x0: linkrate negotiation
  0x1: Host 12G TX train
  0x2: Disk 12G TX train
  0x3: SAS PHY CTRL DFX 0
  0x4: SAS PHY CTRL DFX 1
  0x5: SAS PCS DFX
  other: linkrate negotiation
dump_mask: The masked hardware status bit will not be updated.
dump_mode: determines how to dump data after trigger signal is generated.
  0x0: dump forever
  0x1: dump 32 data after trigger signal is generated
  0x2: no more dump after trigger signal is generated
trigger_mode: determines the trigger mode, level or edge.
  0x0: dump when trigger signal changed
  0x1: dump when trigger signal's level equal to trigger_level
  0x2: dump when trigger signal's level different from trigger_level
trigger_level: determines the trigger level.
trigger_msk: mask trigger signal

The user can get 32-byte values from hardware by reading the rd_data.
These values consitute the status record of the hardware at different time
points.

Link: https://lore.kernel.org/r/1611659068-131975-6-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: hisi_sas: Flush workqueue in hisi_sas_v3_remove()

If the controller reset occurs at the same time as driver removal, it may
be possible that the interrupts have been released prior to the host
softreset, and calling pci_irq_vector() there causes a WARN:

WARNING: CPU: 37 PID: 1542 /pci/msi.c:1275 pci_irq_vector+0xc0/0xd0
Call trace:
pci_irq_vector+0xc0/0xd0
disable_host_v3_hw+0x58/0x5b0 [hisi_sas_v3_hw]
soft_reset_v3_hw+0x40/0xc0 [hisi_sas_v3_hw]
hisi_sas_controller_reset+0x150/0x260 [hisi_sas_main]
hisi_sas_rst_work_handler+0x3c/0x58 [hisi_sas_main]

To fix, flush the driver workqueue prior to releasing the interrupts to
ensure any resets have been completed.

Link: https://lore.kernel.org/r/1611659068-131975-5-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: hisi_sas: Enable debugfs support by default

Add a config option to enable debugfs support by default. And if debugfs
support is enabled by default, dump count default value is increased to 50
as generally users want something bigger than the current default in that
situation.

Link: https://lore.kernel.org/r/1611659068-131975-4-git-send-email-john.garry@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: hisi_sas: Don't check .nr_hw_queues in hisi_sas_task_prep()

Now that v2 and v3 hw expose their HW queues (and so shost.nr_hw_queues is
set), remove the conditional checks in hisi_sas_task_prep().

This change would affect v1 HW performance (as it does not expose HW
queues), but nobody uses it and support may be dropped soon.

Link: https://lore.kernel.org/r/1611659068-131975-3-git-send-email-john.garry@huawei.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: hisi_sas: Remove deferred probe check in hisi_sas_v2_probe()

The platform_get_irq() check for -EPROBE_DEFER was to ensure that all the
steps to add the SCSI host are not done and then only to realise that the
probe needs to be deferred.

However, since there is now an earlier check for this in
hisi_sas_interrupt_preinit(), this check is superfluous and may be removed.

Link: https://lore.kernel.org/r/1611659068-131975-2-git-send-email-john.garry@huawei.com
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: lpfc: Add auto select on IRQ_POLL

lpfc depends on irq_poll library, but it is not selected automatically.
When irq_poll is not selected, compiling it can run into following error

ERROR: modpost: "irq_poll_init" [drivers/scsi/lpfc/lpfc.ko] undefined!
ERROR: modpost: "irq_poll_sched" [drivers/scsi/lpfc/lpfc.ko] undefined!
ERROR: modpost: "irq_poll_complete" [drivers/scsi/lpfc/lpfc.ko] undefined!

Link: https://lore.kernel.org/r/20210126000554.309858-1-ztong0001@gmail.com
Reviewed-by: James Smart <jsmart2021@gmail.com>
Signed-off-by: Tong Zhang <ztong0001@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ncr53c8xx: Fix typos

The patch to switch using SAM status values had some typos; fix them up.

Link: https://lore.kernel.org/r/20210125085415.70574-1-hare@suse.de
Fixes: 491152c7c3b5 ("scsi: ncr53c8xx: Use SAM status values")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: lpfc: Fix ancient double free

The "pmb" pointer is freed at the start of the function and then freed
again in the error handling code.

Link: https://lore.kernel.org/r/YA6E8rO51hE56SVw@mwanda
Fixes: 92d7f7b0cde3 ("[SCSI] lpfc: NPIV: add NPIV support on top of SLI-3")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: qla2xxx: Fix some memory corruption

This was supposed to be "data" instead of "&data".  The current code will
corrupt the stack.

Link: https://lore.kernel.org/r/YA6E0geUlL9Hs04A@mwanda
Fixes: dbf1f53cfd23 ("scsi: qla2xxx: Implementation to get and manage host, target stats and initiator port")
Acked-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Merge branch '5.11/scsi-fixes' into 5.12/scsi-queue

The UFS core has received a substantial rework this cycle. This in
turn has caused a merge conflict in linux-next. Merge 5.11/scsi-fixes
into 5.12/scsi-queue and resolve the conflict.

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

scsi: qla2xxx: Remove redundant NULL check

Fix below warnings reported by coccicheck:
./drivers/scsi/qla2xxx/qla_init.c:3371:2-7: WARNING: NULL check before
some freeing functions is not needed.
./drivers/scsi/qla2xxx/qla_init.c:7855:5-10: WARNING: NULL check before
some freeing functions is not needed.
./drivers/scsi/qla2xxx/qla_init.c:7916:2-7: WARNING: NULL check before
some freeing functions is not needed.
./drivers/scsi/qla2xxx/qla_init.c:8113:4-18: WARNING: NULL check before
some freeing functions is not needed.
./drivers/scsi/qla2xxx/qla_init.c:8174:2-7: WARNING: NULL check before
some freeing functions is not needed.

Link: https://lore.kernel.org/r/1611306174-92627-1-git-send-email-abaci-bugfix@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Yang Li <abaci-bugfix@linux.alibaba.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: megaraid: Fix ifnullfree.cocci warnings

NULL check before vfree is not needed.

Generated by: scripts/coccinelle/free/ifnullfree.cocci

Link: https://lore.kernel.org/r/alpine.DEB.2.22.394.2012111113060.2669@hadrien
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: kernel test robot <lkp@intel.com>
Signed-off-by: Julia Lawall <julia.lawall@inria.fr>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: qla1280: Fix printk regression

Since Linus Torvalds reinstated KERN_CONT in commit 4bcc595ccd80 ("printk:
reinstate KERN_CONT for printing continuation lines") in 2015, the qla1280
SCSI driver printed a rather ugly and screen real estate wasting multi-line
per device status glibberish during boot. Fix this by adding KERN_CONT as
needed.

Tested on my Sgi Octane: https://youtu.be/Lfqe1SYR2jk

Link: https://lore.kernel.org/r/20201210.223944.388095546873159172.rene@exactcode.com
Signed-off-by: René Rebe <rene@exactcode.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Cleanup WB buffer flush toggle implementation

Delete ufshcd_wb_buf_flush_enable() and ufshcd_wb_buf_flush_disable(). Move
the implementation into ufshcd_wb_toggle_flush().

Link: https://lore.kernel.org/r/20210121185736.12471-1-huobean@gmail.com
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: qla2xxx: Remove unnecessary NULL check

The list iterator can't be NULL so this check is not required.  Removing
the check silences a Smatch warning about inconsistent NULL checking.

    drivers/scsi/qla2xxx/qla_dfs.c:371 qla_dfs_tgt_counters_show()
    error: we previously assumed 'fcport' could be null (see line 372)

Link: https://lore.kernel.org/r/YAkaaSrhn1mFqyHy@mwanda
Acked-by: Saurav Kashyap <skashyap@marvell.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: qla2xxx: Assign boolean values to a bool variable

Fix the following coccicheck warnings:

./drivers/scsi/qla2xxx/qla_isr.c:780:2-18: WARNING: Assignment
of 0/1 to bool variable.

Link: https://lore.kernel.org/r/1611127919-56551-1-git-send-email-abaci-bugfix@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: Jiapeng Zhong <abaci-bugfix@linux.alibaba.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: lpfc: Fix kerneldoc inconsistency in lpfc_sli4_dump_page_a0()

Comment did not match function signature.

Link: https://lore.kernel.org/r/20210119205022.40000-1-ericcurtin17@gmail.com
Signed-off-by: Eric Curtin <ericcurtin17@gmail.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: mpt3sas: Simplify bool comparison

Fix the following coccicheck warning:

./drivers/scsi/mpt3sas/mpt3sas_base.c:2424:5-20: WARNING: Comparison of 0/1
to bool variable

Link: https://lore.kernel.org/r/1610355253-25960-1-git-send-email-abaci-bugfix@linux.alibaba.com
Reported-by: Abaci Robot <abaci@linux.alibaba.com>
Signed-off-by: YANG LI <abaci-bugfix@linux.alibaba.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Remove temporarily-added _gfp() API variants

These variants were added for bisectability. Remove them, as all call sites
have now been convertd to use the original API.

Link: https://lore.kernel.org/r/20210118100955.1761652-20-a.darwish@linutronix.de
Cc: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: mvsas: Switch back to original libsas event notifiers

libsas event notifiers required an extension where gfp_t flags must be
explicitly passed. For bisectability, a temporary _gfp() variant of such
functions were added. All call sites then got converted use the _gfp()
variants and explicitly pass GFP context. Having no callers left, the
original libsas notifiers were then modified to accept gfp_t flags by
default.

Switch back to the original libas API, while still passing GFP context.
The libsas _gfp() variants will be removed afterwards.

Link: https://lore.kernel.org/r/20210118100955.1761652-19-a.darwish@linutronix.de
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Switch back to original libsas event notifiers

libsas event notifiers required an extension where gfp_t flags must be
explicitly passed. For bisectability, a temporary _gfp() variant of such
functions were added. All call sites then got converted use the _gfp()
variants and explicitly pass GFP context. Having no callers left, the
original libsas notifiers were then modified to accept gfp_t flags by
default.

Switch back to the original libas API, while still passing GFP context.
The libsas _gfp() variants will be removed afterwards.

Link: https://lore.kernel.org/r/20210118100955.1761652-18-a.darwish@linutronix.de
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Switch back to original event notifiers API

libsas event notifiers required an extension where gfp_t flags must be
explicitly passed. For bisectability, a temporary _gfp() variant of such
functions were added. All call sites then got converted use the _gfp()
variants and explicitly pass GFP context. Having no callers left, the
original libsas notifiers were then modified to accept gfp_t flags by
default.

Switch back to the original event notifiers API, while still passing GFP
context.  The _gfp() notifier variants will be removed afterwards.

Link: https://lore.kernel.org/r/20210118100955.1761652-17-a.darwish@linutronix.de
Cc: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: pm80xx: Switch back to original libsas event notifiers

libsas event notifiers required an extension where gfp_t flags must be
explicitly passed. For bisectability, a temporary _gfp() variant of such
functions were added. All call sites then got converted use the _gfp()
variants and explicitly pass GFP context. Having no callers left, the
original libsas notifiers were then modified to accept gfp_t flags by
default.

Switch back to the original libas API, while still passing GFP context.
The libsas _gfp() variants will be removed afterwards.

Link: https://lore.kernel.org/r/20210118100955.1761652-16-a.darwish@linutronix.de
Cc: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: aic94xx: Switch back to original libsas event notifiers

libsas event notifiers required an extension where gfp_t flags must be
explicitly passed. For bisectability, a temporary _gfp() variant of such
functions were added. All call sites then got converted use the _gfp()
variants and explicitly pass GFP context. Having no callers left, the
original libsas notifiers were then modified to accept gfp_t flags by
default.

Switch back to the original libas API, while still passing GFP context.
The libsas _gfp() variants will be removed afterwards.

Link: https://lore.kernel.org/r/20210118100955.1761652-15-a.darwish@linutronix.de
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: hisi_sas: Switch back to original libsas event notifiers

libsas event notifiers required an extension where gfp_t flags must be
explicitly passed. For bisectability, a temporary _gfp() variant of such
functions were added. All call sites then got converted use the _gfp()
variants and explicitly pass GFP context. Having no callers left, the
original libsas notifiers were then modified to accept gfp_t flags by
default.

Switch back to the original libas API, while still passing GFP context.
The libsas _gfp() variants will be removed afterwards.

Link: https://lore.kernel.org/r/20210118100955.1761652-14-a.darwish@linutronix.de
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Add gfp_t flags parameter to event notifications

All call-sites of below libsas APIs:

  - sas_alloc_event()
  - sas_notify_port_event()
  - sas_notify_phy_event()

have been converted to use the _gfp()-suffixed version.  Modify the
original APIs above to take a gfp_t flags parameter by default.

For bisectability, call-sites will be modified again to use the original
libsas APIs (while passing gfp_t). The temporary _gfp()-suffixed versions
can then be removed.

Link: https://lore.kernel.org/r/20210118100955.1761652-13-a.darwish@linutronix.de
Cc: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: hisi_sas: Pass gfp_t flags to libsas event notifiers

Use the new libsas event notifiers API, which requires callers to
explicitly pass the gfp_t memory allocation flags.

Below are the context analysis for modified functions:

=> hisi_sas_bytes_dmaed():

Since it is invoked from both process and atomic contexts, let its callers
pass the gfp_t flags:

  * hisi_sas_main.c:
  ------------------

    hisi_sas_phyup_work(): workqueue context
      -> hisi_sas_bytes_dmaed(..., GFP_KERNEL)

    hisi_sas_controller_reset_done(): has an msleep()
      -> hisi_sas_rescan_topology()
        -> hisi_sas_phy_down()
          -> hisi_sas_bytes_dmaed(..., GFP_KERNEL)

    hisi_sas_debug_I_T_nexus_reset(): calls wait_for_completion_timeout()
      -> hisi_sas_phy_down()
        -> hisi_sas_bytes_dmaed(..., GFP_KERNEL)

  * hisi_sas_v1_hw.c:
  -------------------

    int_abnormal_v1_hw(): irq handler
      -> hisi_sas_phy_down()
        -> hisi_sas_bytes_dmaed(..., GFP_ATOMIC)

  * hisi_sas_v[23]_hw.c:
  ----------------------

    int_phy_updown_v[23]_hw(): irq handler
      -> phy_down_v[23]_hw()
        -> hisi_sas_phy_down()
          -> hisi_sas_bytes_dmaed(..., GFP_ATOMIC)

=> int_bcast_v1_hw() and phy_bcast_v3_hw():

Both are invoked exclusively from irq handlers. Pass GFP_ATOMIC.

Link: https://lore.kernel.org/r/20210118100955.1761652-12-a.darwish@linutronix.de
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: aic94xx: Pass gfp_t flags to libsas event notifiers

Use the new libsas event notifiers API, which requires callers to
explicitly pass the gfp_t memory allocation flags.

Context analysis:

  aic94xx_hwi.c: asd_dl_tasklet_handler()
    -> asd_ascb::tasklet_complete()
    == escb_tasklet_complete()
      -> aic94xx_scb.c: asd_phy_event_tasklet()
      -> aic94xx_scb.c: asd_bytes_dmaed_tasklet()
      -> aic94xx_scb.c: asd_link_reset_err_tasklet()
      -> aic94xx_scb.c: asd_primitive_rcvd_tasklet()

All functions are invoked by escb_tasklet_complete(), which is invoked by
the tasklet handler. Pass GFP_ATOMIC.

Link: https://lore.kernel.org/r/20210118100955.1761652-11-a.darwish@linutronix.de
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: pm80xx: Pass gfp_t flags to libsas event notifiers

Use the new libsas event notifiers API, which requires callers to
explicitly pass the gfp_t memory allocation flags.

Call chain analysis, pm8001_hwi.c:

  pm8001_interrupt_handler_msix() || pm8001_interrupt_handler_intx() || pm8001_tasklet()
    -> PM8001_CHIP_DISP->isr() = pm80xx_chip_isr()
      -> process_oq [spin_lock_irqsave(&pm8001_ha->lock, ...)]
        -> process_one_iomb()
          -> mpi_hw_event()
            -> hw_event_sas_phy_up()
              -> pm8001_bytes_dmaed()
            -> hw_event_sata_phy_up
              -> pm8001_bytes_dmaed()

All functions are invoked by process_one_iomb(), which is invoked by the
interrupt service routine and the tasklet handler. A similar call chain is
also found at pm80xx_hwi.c. Pass GFP_ATOMIC.

For pm8001_sas.c, pm8001_phy_control() runs in task context as it calls
wait_for_completion() and msleep().  Pass GFP_KERNEL.

Link: https://lore.kernel.org/r/20210118100955.1761652-10-a.darwish@linutronix.de
Cc: Jack Wang <jinpu.wang@cloud.ionos.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Pass gfp_t flags to event notifiers

Use the new libsas event notifiers API, which requires callers to
explicitly pass the gfp_t memory allocation flags.

Context analysis:

  - sas_enable_revalidation(): process, acquires mutex
  - sas_resume_ha(): process, calls wait_event_timeout()

Link: https://lore.kernel.org/r/20210118100955.1761652-9-a.darwish@linutronix.de
Cc: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Pass gfp_t flags in isci_port_bc_change_received()

Use the new libsas event notifiers API, which requires callers to
explicitly pass the gfp_t memory allocation flags.

libsas sas_notify_port_event() is called from
isci_port_bc_change_received(). Below is the context analysis for all of
its call chains:

host.c: sci_controller_error_handler(): atomic, irq handler     (*)
OR host.c: sci_controller_completion_handler(), atomic, tasklet (*)
  -> sci_controller_process_completions()
    -> sci_controller_event_completion()
      -> phy.c: sci_phy_event_handler()
        -> port.c: sci_port_broadcast_change_received()
          -> isci_port_bc_change_received()

host.c: isci_host_init()                                        (@)
spin_lock_irq(isci_host::scic_lock)
  -> sci_controller_initialize(), atomic                        (*)
    -> port_config.c: sci_port_configuration_agent_initialize()
      -> sci_mpc_agent_validate_phy_configuration()
        -> port.c: sci_port_add_phy()
          -> sci_port_set_phy()
            -> phy.c: sci_phy_set_port()
              -> port.c: sci_port_broadcast_change_received()
                -> isci_port_bc_change_received()

port_config.c: apc_agent_timeout(), atomic, timer callback      (*)
  -> sci_apc_agent_configure_ports()
    -> port.c: sci_port_add_phy()
      -> sci_port_set_phy()
        -> phy.c: sci_phy_set_port()
          -> port.c: sci_port_broadcast_change_received()
            -> isci_port_bc_change_received()

phy.c: enter SCI state: *SCI_PHY_STOPPED*                       # Cont. from [1]
  -> sci_phy_stopped_state_enter()
    -> host.c: sci_controller_link_down()
      -> ->link_down_handler()
      == port_config.c: sci_apc_agent_link_down()
        -> port.c: sci_port_remove_phy()
          -> sci_port_clear_phy()
            -> phy.c: sci_phy_set_port()
              -> port.c: sci_port_broadcast_change_received()
                -> isci_port_bc_change_received()

phy.c: enter SCI state: *SCI_PHY_STARTING*                      # Cont. from [2]
  -> sci_phy_starting_state_enter()
    -> host.c: sci_controller_link_down()
      -> ->link_down_handler()
      == port_config.c: sci_apc_agent_link_down()
        -> port.c: sci_port_remove_phy()
          -> sci_port_clear_phy()
            -> phy.c: sci_phy_set_port()
              -> port.c: sci_port_broadcast_change_received()
                -> isci_port_bc_change_received()

[1] Call chains for entering state: *SCI_PHY_STOPPED*
-----------------------------------------------------

host.c: isci_host_init()                                        (@)
spin_lock_irq(isci_host::scic_lock)
  -> sci_controller_initialize(), atomic                        (*)
      -> phy.c: sci_phy_initialize()
        -> phy.c: sci_phy_link_layer_initialization()
          -> phy.c: sci_change_state(SCI_PHY_STOPPED)

init.c: PCI ->remove() || PM_OPS ->suspend,  process context    (+)
  -> host.c: isci_host_deinit()
    -> sci_controller_stop_phys()
      -> phy.c: sci_phy_stop()
-> sci_change_state(SCI_PHY_STOPPED)

phy.c: isci_phy_control()
spin_lock_irqsave(isci_host::scic_lock, )
  -> sci_phy_stop(), atomic                                     (*)
    -> sci_change_state(SCI_PHY_STOPPED)

[2] Call chains for entering state: *SCI_PHY_STARTING*
------------------------------------------------------

phy.c: phy_sata_timeout(), atimer, timer callback               (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> sci_change_state(SCI_PHY_STARTING)

host.c: phy_startup_timeout(), atomic, timer callback           (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> sci_controller_start_next_phy()
    -> sci_phy_start()
      -> sci_change_state(SCI_PHY_STARTING)

host.c: isci_host_start()                                       (@)
spin_lock_irq(isci_host::scic_lock)
  -> sci_controller_start(), atomic                             (*)
    -> sci_controller_start_next_phy()
      -> sci_phy_start()
        -> sci_change_state(SCI_PHY_STARTING)

phy.c: Enter SCI state *SCI_PHY_SUB_FINAL*                      # Cont. from [2A]
  -> sci_change_state(SCI_PHY_SUB_FINAL)
    -> sci_phy_starting_final_substate_enter()
      -> sci_change_state(SCI_PHY_READY)
        -> Enter SCI state: *SCI_PHY_READY*
          -> sci_phy_ready_state_enter()
            -> host.c: sci_controller_link_up()
              -> sci_controller_start_next_phy()
                -> sci_phy_start()
                  -> sci_change_state(SCI_PHY_STARTING)

phy.c: sci_phy_event_handler(), atomic, discussed earlier       (*)
  -> sci_change_state(SCI_PHY_STARTING), 11 instances

port.c: isci_port_perform_hard_reset()
spin_lock_irqsave(isci_host::scic_lock, )
  -> port.c: sci_port_hard_reset(), atomic                      (*)
    -> phy.c: sci_phy_reset()
      -> sci_change_state(SCI_PHY_RESETTING)
        -> enter SCI PHY state: *SCI_PHY_RESETTING*
          -> sci_phy_resetting_state_enter()
            -> sci_change_state(SCI_PHY_STARTING)

[2A] Call chains for entering SCI state: *SCI_PHY_SUB_FINAL*
------------------------------------------------------------

host.c: power_control_timeout(), atomic, timer callback         (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> phy.c: sci_phy_consume_power_handler()
    -> phy.c: sci_change_state(SCI_PHY_SUB_FINAL)

host.c: sci_controller_error_handler(): atomic, irq handler     (*)
OR host.c: sci_controller_completion_handler(), atomic, tasklet (*)
  -> sci_controller_process_completions()
    -> sci_controller_unsolicited_frame()
      -> phy.c: sci_phy_frame_handler()
        -> sci_change_state(SCI_PHY_SUB_AWAIT_SAS_POWER)
          -> sci_phy_starting_await_sas_power_substate_enter()
            -> host.c: sci_controller_power_control_queue_insert()
              -> phy.c: sci_phy_consume_power_handler()
                -> sci_change_state(SCI_PHY_SUB_FINAL)
        -> sci_change_state(SCI_PHY_SUB_FINAL)
    -> sci_controller_event_completion()
      -> phy.c: sci_phy_event_handler()
        -> sci_phy_start_sata_link_training()
          -> sci_change_state(SCI_PHY_SUB_AWAIT_SATA_POWER)
            -> sci_phy_starting_await_sata_power_substate_enter
              -> host.c: sci_controller_power_control_queue_insert()
                -> phy.c: sci_phy_consume_power_handler()
                  -> sci_change_state(SCI_PHY_SUB_FINAL)

As can be seen from the "(*)" markers above, almost all the call-chains are
atomic. The only exception, marked with "(+)", is a PCI ->remove() and
PM_OPS ->suspend() cold path. Thus, pass GFP_ATOMIC to the libsas port
event notifier.

Note, the now-replaced libsas APIs used in_interrupt() to implicitly decide
which memory allocation type to use.  This was only partially correct, as
it fails to choose the correct GFP flags when just preemption or interrupts
are disabled. Such buggy code paths are marked with "(@)" in the call
chains above.

Link: https://lore.kernel.org/r/20210118100955.1761652-8-a.darwish@linutronix.de
Fixes: 1c393b970e0f ("scsi: libsas: Use dynamic alloced work to avoid sas event lost")
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Pass gfp_t flags in isci_port_link_up()

Use the new libsas event notifiers API, which requires callers to
explicitly pass the gfp_t memory allocation flags.

libsas sas_notify_port_event() is called from isci_port_link_up().  Below
is the context analysis for all of its call chains:

host.c: isci_host_init()                                        (@)
spin_lock_irq(isci_host::scic_lock)
  -> sci_controller_initialize(), atomic                        (*)
    -> port_config.c: sci_port_configuration_agent_initialize()
      -> sci_mpc_agent_validate_phy_configuration()
        -> port.c: sci_port_add_phy()
          -> sci_port_general_link_up_handler()
            -> sci_port_activate_phy()
              -> isci_port_link_up()

port_config.c: apc_agent_timeout(), atomic, timer callback      (*)
  -> sci_apc_agent_configure_ports()
    -> port.c: sci_port_add_phy()
      -> sci_port_general_link_up_handler()
        -> sci_port_activate_phy()
          -> isci_port_link_up()

phy.c: enter SCI state: *SCI_PHY_SUB_FINAL*                     # Cont. from [1]
  -> phy.c: sci_phy_starting_final_substate_enter()
    -> phy.c: sci_change_state(SCI_PHY_READY)
      -> enter SCI state: *SCI_PHY_READY*
        -> phy.c: sci_phy_ready_state_enter()
          -> host.c: sci_controller_link_up()
            -> .link_up_handler()
            == port_config.c: sci_apc_agent_link_up()
              -> port.c: sci_port_link_up()
                -> (continue at [A])
            == port_config.c: sci_mpc_agent_link_up()
      -> port.c: sci_port_link_up()
                -> (continue at [A])

port_config.c: mpc_agent_timeout(), atomic, timer callback      (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> ->link_up_handler()
  == port_config.c: sci_apc_agent_link_up()
    -> port.c: sci_port_link_up()
      -> (continue at [A])
  == port_config.c: sci_mpc_agent_link_up()
    -> port.c: sci_port_link_up()
      -> (continue at [A])

[A] port.c: sci_port_link_up()
  -> sci_port_activate_phy()
    -> isci_port_link_up()
  -> sci_port_general_link_up_handler()
    -> sci_port_activate_phy()
      -> isci_port_link_up()

[1] Call chains for entering SCI state: *SCI_PHY_SUB_FINAL*
-----------------------------------------------------------

host.c: power_control_timeout(), atomic, timer callback         (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> phy.c: sci_phy_consume_power_handler()
    -> phy.c: sci_change_state(SCI_PHY_SUB_FINAL)

host.c: sci_controller_error_handler(): atomic, irq handler     (*)
OR host.c: sci_controller_completion_handler(), atomic, tasklet (*)
  -> sci_controller_process_completions()
    -> sci_controller_unsolicited_frame()
      -> phy.c: sci_phy_frame_handler()
        -> sci_change_state(SCI_PHY_SUB_AWAIT_SAS_POWER)
          -> sci_phy_starting_await_sas_power_substate_enter()
            -> host.c: sci_controller_power_control_queue_insert()
              -> phy.c: sci_phy_consume_power_handler()
                -> sci_change_state(SCI_PHY_SUB_FINAL)
        -> sci_change_state(SCI_PHY_SUB_FINAL)
    -> sci_controller_event_completion()
      -> phy.c: sci_phy_event_handler()
        -> sci_phy_start_sata_link_training()
          -> sci_change_state(SCI_PHY_SUB_AWAIT_SATA_POWER)
            -> sci_phy_starting_await_sata_power_substate_enter
              -> host.c: sci_controller_power_control_queue_insert()
                -> phy.c: sci_phy_consume_power_handler()
                  -> sci_change_state(SCI_PHY_SUB_FINAL)

As can be seen from the "(*)" markers above, all the call-chains are
atomic.  Pass GFP_ATOMIC to libsas port event notifier.

Note, the now-replaced libsas APIs used in_interrupt() to implicitly decide
which memory allocation type to use.  This was only partially correct, as
it fails to choose the correct GFP flags when just preemption or interrupts
are disabled. Such buggy code paths are marked with "(@)" in the call
chains above.

Link: https://lore.kernel.org/r/20210118100955.1761652-7-a.darwish@linutronix.de
Fixes: 1c393b970e0f ("scsi: libsas: Use dynamic alloced work to avoid sas event lost")
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: isci: Pass gfp_t flags in isci_port_link_down()

Use the new libsas event notifiers API, which requires callers to
explicitly pass the gfp_t memory allocation flags.

sas_notify_phy_event() is exclusively called by isci_port_link_down().
Below is the context analysis for all of its call chains:

port.c: port_timeout(), atomic, timer callback                  (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> port_state_machine_change(..., SCI_PORT_FAILED)
    -> enter SCI port state: *SCI_PORT_FAILED*
      -> sci_port_failed_state_enter()
        -> isci_port_hard_reset_complete()
          -> isci_port_link_down()

port.c: isci_port_perform_hard_reset()
spin_lock_irqsave(isci_host::scic_lock, )
  -> port.c: sci_port_hard_reset(), atomic                      (*)
    -> phy.c: sci_phy_reset()
      -> sci_change_state(SCI_PHY_RESETTING)
        -> enter SCI PHY state: *SCI_PHY_RESETTING*
          -> sci_phy_resetting_state_enter()
            -> port.c: sci_port_deactivate_phy()
      -> isci_port_link_down()

port.c: enter SCI port state: *SCI_PORT_READY*                  # Cont. from [1]
  -> sci_port_ready_state_enter()
    -> isci_port_hard_reset_complete()
      -> isci_port_link_down()

phy.c: enter SCI state: *SCI_PHY_STOPPED*                       # Cont. from [2]
  -> sci_phy_stopped_state_enter()
    -> host.c: sci_controller_link_down()
      -> ->link_down_handler()
      == port_config.c: sci_apc_agent_link_down()
        -> port.c: sci_port_remove_phy()
          -> sci_port_deactivate_phy()
            -> isci_port_link_down()
      == port_config.c: sci_mpc_agent_link_down()
        -> port.c: sci_port_link_down()
          -> sci_port_deactivate_phy()
            -> isci_port_link_down()

phy.c: enter SCI state: *SCI_PHY_STARTING*                      # Cont. from [3]
  -> sci_phy_starting_state_enter()
    -> host.c: sci_controller_link_down()
      -> ->link_down_handler()
      == port_config.c: sci_apc_agent_link_down()
        -> port.c: sci_port_remove_phy()
          -> isci_port_link_down()
      == port_config.c: sci_mpc_agent_link_down()
        -> port.c: sci_port_link_down()
          -> sci_port_deactivate_phy()
            -> isci_port_link_down()

[1] Call chains for 'enter SCI port state: *SCI_PORT_READY*'
------------------------------------------------------------

host.c: isci_host_init()                                        (@)
spin_lock_irq(isci_host::scic_lock)
  -> sci_controller_initialize(), atomic                        (*)
    -> port_config.c: sci_port_configuration_agent_initialize()
      -> sci_mpc_agent_validate_phy_configuration()
        -> port.c: sci_port_add_phy()
          -> sci_port_general_link_up_handler()
            -> port_state_machine_change(, SCI_PORT_READY)
              -> enter port state *SCI_PORT_READY*

host.c: isci_host_start()                                       (@)
spin_lock_irq(isci_host::scic_lock)
  -> host.c: sci_controller_start(), atomic                     (*)
    -> host.c: sci_port_start()
      -> port.c: port_state_machine_change(, SCI_PORT_READY)
        -> enter port state *SCI_PORT_READY*

port_config.c: apc_agent_timeout(), atomic, timer callback      (*)
  -> sci_apc_agent_configure_ports()
    -> port.c: sci_port_add_phy()
      -> sci_port_general_link_up_handler()
        -> port_state_machine_change(, SCI_PORT_READY)
          -> enter port state *SCI_PORT_READY*

port_config.c: mpc_agent_timeout(), atomic, timer callback      (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> ->link_up_handler()
  == port.c: sci_apc_agent_link_up()
    -> sci_port_general_link_up_handler()
      -> port_state_machine_change(, SCI_PORT_READY)
        -> enter port state *SCI_PORT_READY*
  == port.c: sci_mpc_agent_link_up()
    -> port.c: sci_port_link_up()
      -> sci_port_general_link_up_handler()
        -> port_state_machine_change(, SCI_PORT_READY)
          -> enter port state *SCI_PORT_READY*

phy.c: enter SCI state: SCI_PHY_SUB_FINAL                       # Cont. from [1A]
  -> sci_phy_starting_final_substate_enter()
    -> sci_change_state(SCI_PHY_READY)
      -> enter SCI state: *SCI_PHY_READY*
        -> sci_phy_ready_state_enter()
          -> host.c: sci_controller_link_up()
            -> port_agent.link_up_handler()
            == port_config.c: sci_apc_agent_link_up()
              -> port.c: sci_port_link_up()
                -> sci_port_general_link_up_handler()
                  -> port_state_machine_change(, SCI_PORT_READY)
                    -> enter port state *SCI_PORT_READY*
            == port_config.c: sci_mpc_agent_link_up()
              -> port.c: sci_port_link_up()
                -> sci_port_general_link_up_handler()
                  -> port_state_machine_change(, SCI_PORT_READY)
                    -> enter port state *SCI_PORT_READY*

[1A] Call chains for entering SCI state: *SCI_PHY_SUB_FINAL*
------------------------------------------------------------

host.c: power_control_timeout(), atomic, timer callback         (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> phy.c: sci_phy_consume_power_handler()
    -> phy.c: sci_change_state(SCI_PHY_SUB_FINAL)

host.c: sci_controller_error_handler(): atomic, irq handler     (*)
OR host.c: sci_controller_completion_handler(), atomic, tasklet (*)
  -> sci_controller_process_completions()
    -> sci_controller_unsolicited_frame()
      -> phy.c: sci_phy_frame_handler()
        -> sci_change_state(SCI_PHY_SUB_AWAIT_SAS_POWER)
          -> sci_phy_starting_await_sas_power_substate_enter()
            -> host.c: sci_controller_power_control_queue_insert()
              -> phy.c: sci_phy_consume_power_handler()
                -> sci_change_state(SCI_PHY_SUB_FINAL)
        -> sci_change_state(SCI_PHY_SUB_FINAL)
    -> sci_controller_event_completion()
      -> phy.c: sci_phy_event_handler()
        -> sci_phy_start_sata_link_training()
          -> sci_change_state(SCI_PHY_SUB_AWAIT_SATA_POWER)
            -> sci_phy_starting_await_sata_power_substate_enter
              -> host.c: sci_controller_power_control_queue_insert()
                -> phy.c: sci_phy_consume_power_handler()
                  -> sci_change_state(SCI_PHY_SUB_FINAL)

[2] Call chains for entering state: *SCI_PHY_STOPPED*
-----------------------------------------------------

host.c: isci_host_init()                                        (@)
spin_lock_irq(isci_host::scic_lock)
  -> sci_controller_initialize(), atomic                        (*)
      -> phy.c: sci_phy_initialize()
        -> phy.c: sci_phy_link_layer_initialization()
          -> phy.c: sci_change_state(SCI_PHY_STOPPED)

init.c: PCI ->remove() || PM_OPS ->suspend,  process context    (+)
  -> host.c: isci_host_deinit()
    -> sci_controller_stop_phys()
      -> phy.c: sci_phy_stop()
-> sci_change_state(SCI_PHY_STOPPED)

phy.c: isci_phy_control()
spin_lock_irqsave(isci_host::scic_lock, )
  -> sci_phy_stop(), atomic                                     (*)
    -> sci_change_state(SCI_PHY_STOPPED)

[3] Call chains for entering state: *SCI_PHY_STARTING*
------------------------------------------------------

phy.c: phy_sata_timeout(), atimer, timer callback               (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> sci_change_state(SCI_PHY_STARTING)

host.c: phy_startup_timeout(), atomic, timer callback           (*)
spin_lock_irqsave(isci_host::scic_lock, )
  -> sci_controller_start_next_phy()
    -> sci_phy_start()
      -> sci_change_state(SCI_PHY_STARTING)

host.c: isci_host_start()                                       (@)
spin_lock_irq(isci_host::scic_lock)
  -> sci_controller_start(), atomic                             (*)
    -> sci_controller_start_next_phy()
      -> sci_phy_start()
        -> sci_change_state(SCI_PHY_STARTING)

phy.c: Enter SCI state *SCI_PHY_SUB_FINAL*, atomic, check above (*)
  -> sci_change_state(SCI_PHY_SUB_FINAL)
    -> sci_phy_starting_final_substate_enter()
      -> sci_change_state(SCI_PHY_READY)
        -> Enter SCI state: *SCI_PHY_READY*
          -> sci_phy_ready_state_enter()
            -> host.c: sci_controller_link_up()
              -> sci_controller_start_next_phy()
                -> sci_phy_start()
                  -> sci_change_state(SCI_PHY_STARTING)

phy.c: sci_phy_event_handler(), atomic, discussed earlier       (*)
  -> sci_change_state(SCI_PHY_STARTING), 11 instances

phy.c: enter SCI state: *SCI_PHY_RESETTING*, atomic, discussed  (*)
  -> sci_phy_resetting_state_enter()
    -> sci_change_state(SCI_PHY_STARTING)

As can be seen from the "(*)" markers above, almost all the call-chains are
atomic. The only exception, marked with "(+)", is a PCI ->remove() and
PM_OPS ->suspend() cold path. Thus, pass GFP_ATOMIC to the libsas phy event
notifier.

Note, The now-replaced libsas APIs used in_interrupt() to implicitly decide
which memory allocation type to use.  This was only partially correct, as
it fails to choose the correct GFP flags when just preemption or interrupts
are disabled. Such buggy code paths are marked with "(@)" in the call
chains above.

Link: https://lore.kernel.org/r/20210118100955.1761652-6-a.darwish@linutronix.de
Fixes: 1c393b970e0f ("scsi: libsas: Use dynamic alloced work to avoid sas event lost")
Cc: Artur Paszkiewicz <artur.paszkiewicz@intel.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: mvsas: Pass gfp_t flags to libsas event notifiers

mvsas calls the non _gfp version of the libsas event notifiers API, leading
to the buggy call chains below:

  mvsas/mv_sas.c: mvs_work_queue() [process context]
  spin_lock_irqsave(mvs_info::lock, )
    -> libsas/sas_event.c: sas_notify_phy_event()
      -> sas_alloc_event()
        -> in_interrupt() = false
          -> invalid GFP_KERNEL allocation
    -> libsas/sas_event.c: sas_notify_port_event()
      -> sas_alloc_event()
        -> in_interrupt() = false
          -> invalid GFP_KERNEL allocation

Use the new event notifiers API instead, which requires callers to
explicitly pass the gfp_t memory allocation flags.

Below are context analysis for the modified functions:

=> mvs_bytes_dmaed():

Since it is invoked from both process and atomic contexts, let its callers
pass the gfp_t flags. Call chains:

  scsi_scan.c: do_scsi_scan_host() [has msleep()]
    -> shost->hostt->scan_start()
    -> [mvsas/mv_init.c: Scsi_Host::scsi_host_template .scan_start = mvs_scan_start()]
    -> mvsas/mv_sas.c: mvs_scan_start()
      -> mvs_bytes_dmaed(..., GFP_KERNEL)

  mvsas/mv_sas.c: mvs_work_queue()
  spin_lock_irqsave(mvs_info::lock,)
    -> mvs_bytes_dmaed(..., GFP_ATOMIC)

  mvsas/mv_64xx.c: mvs_64xx_isr() || mvsas/mv_94xx.c: mvs_94xx_isr()
    -> mvsas/mv_chips.h: mvs_int_full()
      -> mvsas/mv_sas.c: mvs_int_port()
        -> mvs_bytes_dmaed(..., GFP_ATOMIC);

=> mvs_work_queue():

Invoked from process context, but it calls all the libsas event notifier
APIs under a spin_lock_irqsave(). Pass GFP_ATOMIC.

Link: https://lore.kernel.org/r/20210118100955.1761652-5-a.darwish@linutronix.de
Fixes: 1c393b970e0f ("scsi: libsas: Use dynamic alloced work to avoid sas event lost")
Cc: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Introduce a _gfp() variant of event notifiers

sas_alloc_event() uses in_interrupt() to decide which allocation should be
used.

The usage of in_interrupt() in drivers is phased out and Linus clearly
requested that code which changes behaviour depending on context should
either be separated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

The in_interrupt() check is also only partially correct, because it fails
to choose the correct code path when just preemption or interrupts are
disabled. For example, as in the following call chain:

  mvsas/mv_sas.c: mvs_work_queue() [process context]
  spin_lock_irqsave(mvs_info::lock, )
    -> libsas/sas_event.c: sas_notify_phy_event()
      -> sas_alloc_event()
        -> in_interrupt() = false
          -> invalid GFP_KERNEL allocation
    -> libsas/sas_event.c: sas_notify_port_event()
      -> sas_alloc_event()
        -> in_interrupt() = false
          -> invalid GFP_KERNEL allocation

Introduce sas_alloc_event_gfp(), sas_notify_port_event_gfp(), and
sas_notify_phy_event_gfp(), which all behave like the non _gfp() variants
but use a caller-passed GFP mask for allocations.

For bisectability, all callers will be modified first to pass GFP context,
then the non _gfp() libsas API variants will be modified to take a gfp_t by
default.

Link: https://lore.kernel.org/r/20210118100955.1761652-4-a.darwish@linutronix.de
Fixes: 1c393b970e0f ("scsi: libsas: Use dynamic alloced work to avoid sas event lost")
Cc: Jason Yan <yanaijie@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Remove notifier indirection

LLDDs report events to libsas with .notify_port_event and .notify_phy_event
callbacks.

These callbacks are fixed and so there is no reason why the functions
cannot be called directly, so do that.

This neatens the code slightly, makes it more obvious, and reduces function
pointer usage, which is generally a good thing. Downside is that there are
2x more symbol exports.

[a.darwish@linutronix.de: Remove the now unused "sas_ha" local variables]

Link: https://lore.kernel.org/r/20210118100955.1761652-3-a.darwish@linutronix.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: docs: Remove notify_ha_event()

The ->notify_ha_event() hook has long been removed from the libsas event
interface.

Remove it from documentation.

Link: https://lore.kernel.org/r/20210118100955.1761652-2-a.darwish@linutronix.de
Fixes: 042ebd293b86 ("scsi: libsas: kill useless ha_event and do some cleanup")
Cc: stable@vger.kernel.org
Reviewed-by: John Garry <john.garry@huawei.com>
Reviewed-by: Jack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ncr53c8xx: Use SAM status values

Use SAM status values instead of the driver-defined ones.  This also fixes
a potential bug as the driver-defined values declare 'COMMAND TERMINATED'
with a value of 0x20, whereas SCSI-II defines it with a value of 0x22.

Link: https://lore.kernel.org/r/20210113090500.129644-36-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: advansys: Kill driver-defined status byte accessors

Replace the driver-defined status byte accessors with the mid-layer defined
ones.

Link: https://lore.kernel.org/r/20210113090500.129644-35-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: qla2xxx: fc_remote_port_chkready() returns a SCSI result value

fc_remote_port_chkready() returns a SCSI result value, not the port
status. Fix the value returned when the remote port isn't set.

Link: https://lore.kernel.org/r/20210113090500.129644-34-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: storvsc: Return DID_ERROR for invalid commands

ILLEGAL_COMMAND is a sense code, not a driver byte.

Link: https://lore.kernel.org/r/20210113090500.129644-33-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ips: Use correct command completion on error

A non-zero queuecommand() return code means 'busy', i.e. the command hasn't
been submitted. So any command which should be failed need to be completed
via the ->scsi_done() callback with the appropriate result code set.

Link: https://lore.kernel.org/r/20210113090500.129644-32-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: wd33c93: Use SCSI status

Use standard SCSI status and drop usage of the linux-specific ones.

Link: https://lore.kernel.org/r/20210113090500.129644-31-hare@suse.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: esp_scsi: Do not set SCSI message byte

The message byte setting always devolves to COMMAND_COMPLETE so we can drop
setting the message byte in the SCSI result.

Link: https://lore.kernel.org/r/20210113090500.129644-30-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: esp_scsi: Use host byte as last argument to esp_cmd_is_done()

Just pass in the host byte to esp_cmd_is_done() and set the status or
message bytes if the host byte is DID_OK.

Link: https://lore.kernel.org/r/20210113090500.129644-29-hare@suse.de
Acked-by: Finn Thain <fthain@telegraphics.com.au>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: core: Add 'set_status_byte()' accessor

Add the missing 'set_status_byte()' accessor function.

Link: https://lore.kernel.org/r/20210113090500.129644-28-hare@suse.de
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: dpt_i2o: Use DID_ERROR instead of INITIATOR_ERROR message

Change the error code for an invalid SCSI opcode to DID_ERROR.
INITIATOR_ERROR is a scsi parallel message which doesn't apply for RAID
HBAs.

Link: https://lore.kernel.org/r/20210113090500.129644-27-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: mac53c94: Do not set invalid command result

CMD_ACCEPT_MSG is an internal definition and most certainly not a SCSI
status. As the latter gets set during command completion we can drop the
assignment here.

Link: https://lore.kernel.org/r/20210113090500.129644-26-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: atp870u: Use standard definitions

Use standard definitions for SCSI commands and return status instead of the
hardcoded values.

Link: https://lore.kernel.org/r/20210113090500.129644-25-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: ufshcd: Do not set COMMAND_COMPLETE

COMMAND_COMPLETE is defined as '0', so setting it is quite pointless.

Link: https://lore.kernel.org/r/20210113090500.129644-24-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: scsi_debug: Do not set COMMAND_COMPLETE

COMMAND_COMPLETE is defined as '0', so setting it is quite pointless.

Link: https://lore.kernel.org/r/20210113090500.129644-23-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Douglas Gilbert <dgilbert@interlog.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: initio: Drop internal SCSI message definition

Use the standard SCSI message definitions instead of the driver-internal
ones.

Link: https://lore.kernel.org/r/20210113090500.129644-22-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: dc395x: Drop internal SCSI message definitions

Drop the internal SCSI message definitions and use the functions provided
by the SPI transport class.

Link: https://lore.kernel.org/r/20210113090500.129644-21-hare@suse.de
Reported-by: kernel test robot <lkp@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: aic7xxx: aic79xx: Drop internal SCSI message definition

Use the standard SCSI message definitions instead of the driver-internal
ones.

Link: https://lore.kernel.org/r/20210113090500.129644-20-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: nsp_cs: Drop internal SCSI message definition

Use the standard SCSI message definitions instead of the driver-internal
ones.

Link: https://lore.kernel.org/r/20210113090500.129644-19-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: stex: Do not set COMMAND_COMPLETE

COMMAND_COMPLETE is defined as '0', so setting it is quite pointless.

Link: https://lore.kernel.org/r/20210113090500.129644-18-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: hpsa: Do not set COMMAND_COMPLETE

COMMAND_COMPLETE is defined as '0', and it is a SCSI parallel message to
boot. Drop the call to set_msg_byte().

Link: https://lore.kernel.org/r/20210113090500.129644-17-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Acked-by: Don Brace <don.brace@microchip.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: aacraid: Avoid setting message byte on completion

The aacraid controller is a RAID controller and the driver will never see
any SCSI messages. Plus it's quite pointless to set the message byte if the
host byte is already set, as the latter takes precedence during error
recovery.  Drop the message byte values for the final result.

Link: https://lore.kernel.org/r/20210113090500.129644-16-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: zfcp: Do not set COMMAND_COMPLETE

COMMAND_COMPLETE is defined as '0', and it is a SCSI parallel message to
boot. So drop the call to set_msg_byte().

Link: https://lore.kernel.org/r/20210113090500.129644-15-hare@suse.de
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: qla4xxx: Use standard SAM status definitions

Use standard SAM status definitions and drop the driver-defined ones.

Link: https://lore.kernel.org/r/20210113090500.129644-14-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: dc395: Drop private SAM status code definitions

We don't need to duplicate definitions from the common include files.

Link: https://lore.kernel.org/r/20210113090500.129644-13-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: nsp32: Fixup status handling

SCp.status is always the SAM-defined status value, not the Linux
ones. Fixup the one wrong definition.

Link: https://lore.kernel.org/r/20210113090500.129644-12-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: acornscsi: Use standard defines

Use midlayer-defined values and drop the non-existing QUEUE_FULL case; we
are checking the SCSI messages in the switch statement, and QUEUE_FULL is a
SCSI status hence it can never occur here.

Link: https://lore.kernel.org/r/20210113090500.129644-11-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: bfa: Drop driver-defined SCSI status codes

Drop the driver-defined SCSI status codes and use the generic ones instead.

Link: https://lore.kernel.org/r/20210113090500.129644-10-hare@suse.de
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: aic7xxx: aic79xx: Remove driver-defined SAM status definitions

Replace the driver-defined SAM status definitions with the standard
mid-layer defined ones.

Link: https://lore.kernel.org/r/20210113090500.129644-9-hare@suse.de
Reviewed-by: Bart van Assche <bvanassche@acm.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: aic7xxx: aic79xx: Kill pointless forward declarations

Link: https://lore.kernel.org/r/20210113090500.129644-8-hare@suse.de
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: aic7xxx: aic79xx: Whitespace cleanup

Link: https://lore.kernel.org/r/20210113090500.129644-7-hare@suse.de
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: atp870u: Whitespace cleanup

Link: https://lore.kernel.org/r/20210113090500.129644-6-hare@suse.de
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: 3w-sas: Whitespace cleanup

Link: https://lore.kernel.org/r/20210113090500.129644-5-hare@suse.de
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: 3w-9xxx: Whitespace cleanup

Link: https://lore.kernel.org/r/20210113090500.129644-4-hare@suse.de
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: 3w-xxxx: Whitespace cleanup

Link: https://lore.kernel.org/r/20210113090500.129644-3-hare@suse.de
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: Drop gdth driver

The gdth driver refers to a SCSI parallel, PCI-only HBA RAID adapter which
was manufactured by the now-defunct ICP Vortex company, later acquired by
Adaptec and superseded by the aacraid series of controllers.  The driver
itself would require a major overhaul before any modifications can be
attempted, but seeing that it's unlikely to have any users left it should
rather be removed completely.

Link: https://lore.kernel.org/r/20210113090500.129644-2-hare@suse.de
Cautiously-Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: core: Remove in_interrupt() check in transport_handle_cdb_direct()

transport_handle_cdb_direct() uses in_interrupt() to detect if it is safe
to sleep. It produces a stack trace and returns with an error which is
clearly for debugging.

The usage of in_interrupt() in drivers is phased out and Linus clearly
requested that code which changes behaviour depending on context should
either be separated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

transport_handle_cdb_direct() has a comment saying that it may only be
invoked from process context. It invokes transport_generic_new_cmd() which
performs GFP_KERNEL memory allocations. in_interrupt() does not detect all
the contexts where it is invalid to sleep (for the blocking GFP_KERNEL
allocation) as it fails to detect sections with disabled preemption.

Replace the in_interrupt() based check with a might_sleep() annotation.

Link: https://lore.kernel.org/r/20201220203638.43615-7-bigeasy@linutronix.de
Signed-off-by: Ahmed S. Darwish <a.darwish@linutronix.de>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: core: Replace in_interrupt() usage in target_submit_cmd_map_sgls()

target_submit_cmd_map_sgls() uses in_interrupt() to crash if it returns
true.

The usage of in_interrupt() in drivers is phased out and Linus clearly
requested that code which changes behaviour depending on context should
either be separated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

The usage of in_interrupt() is clearly for debugging. might_sleep() is
better at this because it also detects other contexts in which it is not
allowed to sleep, like preempt-disabled section.

Replace BUG_ON(in_interrupt) with might_sleep().

Link: https://lore.kernel.org/r/20201220203638.43615-6-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: alua: Remove in_interrupt() usage in core_alua_check_nonop_delay()

core_alua_check_nonop_delay() uses in_interrupt() to decide if it is safe
to sleep.

The usage of in_interrupt() in drivers is phased out and Linus clearly
requested that code which changes behaviour depending on context should
either be separated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

core_alua_check_nonop_delay() has two callers:

 - target_submit_cmd_map_sgls()
   Kernel doc says it that it must be called from process context. Also has
   a BUG_ON(in_interrupt()).

 - iscsit_setup_scsi_cmd()
   Invokes iscsit_add_reject_cmd() which does GFP_KERNEL allocation and
   target_cmd_init_cdb() which may do GFP_KERNEL allocations.

Remove the in_interrupt() check because all callers are from preemptible
context.

Link: https://lore.kernel.org/r/20201220203638.43615-5-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Redo iscsit_check_session_usage_count() return code

The return value of iscsit_check_session_usage_count() is only checked if
it was not allowed to sleep. If it returns `2' then a timer is prepared. If
it returns something else or if it was allowed to sleep then it is ignored.

Let iscsit_check_session_usage_count() return true if it needs to arm the
timer - otherwise false. This simplifies the code flow of the only caller.

Link: https://lore.kernel.org/r/20201220203638.43615-4-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Avoid in_interrupt() usage in iscsit_check_session_usage_count()

iscsit_check_session_usage_count() uses in_interrupt() to find out if it is
safe to invoke wait_for_completion().

The usage of in_interrupt() in drivers is phased out and Linus clearly
requested that code which changes behaviour depending on context should
either be separated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

There is only one caller of iscsit_check_session_usage_count() which
already has an argument indicating if it is safe to sleep.

Extend iscsit_check_session_usage_count() by an argument indicating if it
may sleep.

Link: https://lore.kernel.org/r/20201220203638.43615-3-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: target: iscsi: Avoid in_interrupt() usage in iscsit_close_session()

iscsit_close_session() uses in_interrupt() to decide if it needs to check
the return value of iscsit_check_session_usage_count() if it was not able
to sleep.

The usage of in_interrupt() in drivers is phased out and Linus clearly
requested that code which changes behaviour depending on context should
either be separated or the context be conveyed in an argument passed by the
caller, which usually knows the context.

iscsit_close_session() has two callers:

 - iscsit_handle_time2retain_timeout()
   A timer_list callback.

 - iscsit_close_connection()
   Runs in preemptible context, acquires a mutex.

Add an argument to iscsit_close_session() indicating if sleeping is
possible.

Link: https://lore.kernel.org/r/20201220203638.43615-2-bigeasy@linutronix.de
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Clean up and refactor clk-scaling feature

Manipulate clock scaling related stuff only if the host capability supports
clock scaling feature to avoid redundant code execution.

Link: https://lore.kernel.org/r/20210120150142.5049-4-stanley.chu@mediatek.com
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Remove redundant null checking of devfreq instance

hba->devfreq is zero-initialized thus it is not required to check its
existence in ufshcd_add_lus() function which is invoked during
initialization only.

Link: https://lore.kernel.org/r/20210120150142.5049-3-stanley.chu@mediatek.com
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Refactor cancelling clkscaling works

Cancelling suspend_work and resume_work is only required while suspending
clk-scaling. Move these two invocations into ufshcd_suspend_clkscaling()
function.

Link: https://lore.kernel.org/r/20210120150142.5049-2-stanley.chu@mediatek.com
Reviewed-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

Revert "Make sure clk scaling happens only when HBA is runtime ACTIVE"

Commit 73cc291c2702 ("scsi: ufs: Make sure clk scaling happens only
when HBA is runtime ACTIVE") is no longer needed since commit
0e9d4ca43ba8 ("scsi: ufs: Protect some contexts from unexpected clock
scaling") is a more mature fix to protect UFS LLD stability from clock
scaling invoked through sysfs nodes by users.

Link: https://lore.kernel.org/r/1611137065-14266-4-git-send-email-cang@codeaurora.org
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Refactor ufshcd_init/exit_clk_scaling/gating()

ufshcd_hba_exit() is always called after ufshcd_exit_clk_scaling() and
ufshcd_exit_clk_gating(). Move ufshcd_exit_clk_scaling/gating() to
ufshcd_hba_exit(). Meanwhile, add dedicated functions to initialize
and remove sysfs nodes of clock scaling/gating to make the code more
readable. Overall functionality remains same.

Link: https://lore.kernel.org/r/1611137065-14266-3-git-send-email-cang@codeaurora.org
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Protect some contexts from unexpected clock scaling

In contexts like suspend, shutdown, and error handling we need to
suspend devfreq to make sure these contexts won't be disturbed by
clock scaling.  However, suspending devfreq is not enough since users
can still trigger a clock scaling by manipulating the devfreq sysfs
nodes like min/max_freq and governor even after devfreq is
suspended. Moreover, mere suspending devfreq cannot synchroinze a
clock scaling which has already been invoked through these sysfs
nodes. Add one more flag in struct clk_scaling and wrap the entire
func ufshcd_devfreq_scale() with the clk_scaling_lock, so that we can
use this flag and clk_scaling_lock to control and synchronize clock
scaling invoked through devfreq sysfs nodes.

Link: https://lore.kernel.org/r/1611137065-14266-2-git-send-email-cang@codeaurora.org
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Can Guo <cang@codeaurora.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Group UFS WB related flags in struct ufs_dev_info

UFS device-related flags should be grouped in ufs_dev_info. Move wb_enabled
and wb_buf_flush_enabled out from struct ufs_hba, group them in struct
ufs_dev_info, and align the names of the structure members vertically.

Link: https://lore.kernel.org/r/20210119163847.20165-6-huobean@gmail.com
Reviewed-by: Can Guo <cang@codeaurora.org>
Acked-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Remove two WB related fields from struct ufs_dev_info

d_wb_alloc_units and d_ext_ufs_feature_sup are only used during WB probe.
They are used to confirm the condition that "if bWriteBoosterBufferType
is set to 01h but dNumSharedWriteBoosterBufferAllocUnits is set to zero,
the WriteBooster feature is disabled", and if UFS device supports WB.

No need to keep them after probing is complete.

Link: https://lore.kernel.org/r/20210119163847.20165-5-huobean@gmail.com
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Update comment in the function ufshcd_wb_probe()

USFHCD supports both WriteBooster "LU dedicated buffer" mode and "shared
buffer" mode. Update the comment accordingly in the function
ufshcd_wb_probe().

Link: https://lore.kernel.org/r/20210119163847.20165-4-huobean@gmail.com
Reviewed-by: Can Guo <cang@codeaurora.org>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: docs: ABI: Add wb_on documentation for new entry wb_on

Adds UFS sysfs documentation for new entry wb_on.

[mkp: fix doc formatting]

Link: https://lore.kernel.org/r/20210119163847.20165-3-huobean@gmail.com
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
fix format

scsi: ufs: Add "wb_on" sysfs node to control WB on/off

Currently UFS WriteBooster driver uses clock scaling up/down to set WB
on/off. For the platforms which don't support UFSHCD_CAP_CLK_SCALING, WB
will be always on. Provide a sysfs attribute to enable/disable WB during
runtime. Write 1/0 to "wb_on" sysfs node to enable/disable UFS WB.

Link: https://lore.kernel.org/r/20210119163847.20165-2-huobean@gmail.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Reviewed-by: Stanley Chu <stanley.chu@mediatek.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: ufs-exynos: Use UFSHCD_QUIRK_ALIGN_SG_WITH_PAGE_SIZE

Exynos needs scatterlist entries aligned to page size because it isn't
capable of transferring data contained in one DATA IN operation to seversal
areas in memory.

Link: https://lore.kernel.org/r/80d7e27d6ec537e650a6bd74897b6c60618efcdc.1611026909.git.kwmad.kim@samsung.com
Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Introduce a quirk to allow only page-aligned sg entries

Some SoCs require a single scatterlist entry for smaller than page size,
i.e. 4KB. When dispatching commands with more than one scatterlist entry
under 4KB in size the following behavior is observed:

A command to read a block range is dispatched with two scatterlist entries
that are named AAA and BBB. After dispatching, the host builds two PRDT
entries and during transmission, device sends just one DATA IN because
device doesn't care about host DMA. The host then transfers the combined
amount of data from start address of the area named AAA. As a consequence,
the area that follows AAA in memory would be corrupted.

    |<------------->|
    +-------+------------         +-------+
    +  AAA  + (corrupted)   ...   +  BBB  +
    +-------+------------         +-------+

To avoid this we need to enforce page size alignment for sg entries.

Link: https://lore.kernel.org/r/56dddef94f60bd9466fd77e69f64bbbd657ed2a1.1611026909.git.kwmad.kim@samsung.com
Signed-off-by: Kiwoong Kim <kwmad.kim@samsung.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: ufs: Delete redundant if statement in ufshcd_intr()

Once going into while-do loop, intr_status is already true, this
if-statement is redundant, remove it.

Link: https://lore.kernel.org/r/20210118201233.3043-1-huobean@gmail.com
Reviewed-by: Avri Altman <avri.altman@wdc.com>
Signed-off-by: Bean Huo <beanhuo@micron.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: qla2xxx: Fix description for parameter ql2xenforce_iocb_limit

Parameter ql2xenforce_iocb_limit is enabled by default.

Link: https://lore.kernel.org/r/20210118184922.23793-1-ematsumiya@suse.de
Fixes: 89c72f4245a8 ("scsi: qla2xxx: Add IOCB resource tracking")
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Signed-off-by: Enzo Matsumiya <ematsumiya@suse.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>