linux-toradex.git/include/scsi/libsas.h, branch v5.0

scsi: libsas: dynamically allocate and free ata host

2018-06-20T02:02:25+00:00

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

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

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

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

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

Fixes: b6240a4df018 ("scsi: libsas: add transport class for ATA devices")
Signed-off-by: Jason Yan 
CC: John Garry 
CC: Taras Kondratiuk 
CC: Tejun Heo 
Acked-by: Tejun Heo 
Signed-off-by: Martin K. Petersen

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2018-01-31T19:23:28+00:00

Pull SCSI updates from James Bottomley:
 "This is mostly updates of the usual driver suspects: arcmsr,
  scsi_debug, mpt3sas, lpfc, cxlflash, qla2xxx, aacraid, megaraid_sas,
  hisi_sas.

  We also have a rework of the libsas hotplug handling to make it more
  robust, a slew of 32 bit time conversions and fixes, and a host of the
  usual minor updates and style changes. The biggest potential for
  regressions is the libsas hotplug changes, but so far they seem stable
  under testing"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (313 commits)
  scsi: qla2xxx: Fix logo flag for qlt_free_session_done()
  scsi: arcmsr: avoid do_gettimeofday
  scsi: core: Add VENDOR_SPECIFIC sense code definitions
  scsi: qedi: Drop cqe response during connection recovery
  scsi: fas216: fix sense buffer initialization
  scsi: ibmvfc: Remove unneeded semicolons
  scsi: hisi_sas: fix a bug in hisi_sas_dev_gone()
  scsi: hisi_sas: directly attached disk LED feature for v2 hw
  scsi: hisi_sas: devicetree: bindings: add LED feature for v2 hw
  scsi: megaraid_sas: NVMe passthrough command support
  scsi: megaraid: use ktime_get_real for firmware time
  scsi: fnic: use 64-bit timestamps
  scsi: qedf: Fix error return code in __qedf_probe()
  scsi: devinfo: fix format of the device list
  scsi: qla2xxx: Update driver version to 10.00.00.05-k
  scsi: qla2xxx: Add XCB counters to debugfs
  scsi: qla2xxx: Fix queue ID for async abort with Multiqueue
  scsi: qla2xxx: Fix warning for code intentation in __qla24xx_handle_gpdb_event()
  scsi: qla2xxx: Fix warning during port_name debug print
  scsi: qla2xxx: Fix warning in qla2x00_async_iocb_timeout()
  ...

scsi: libsas: direct call probe and destruct

2018-01-11T04:24:02+00:00

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

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

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

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

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

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

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

[mkp: kbuild test robot warning]

Signed-off-by: Jason Yan 
CC: John Garry 
CC: Johannes Thumshirn 
CC: Ewan Milne 
CC: Christoph Hellwig 
CC: Tomas Henzl 
CC: Dan Williams 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Martin K. Petersen

scsi: libsas: Use new workqueue to run sas event and disco event

2018-01-09T02:59:28+00:00

Now all libsas works are queued to scsi host workqueue, include sas
event work post by LLDD and sas discovery work, and a sas hotplug flow
may be divided into several works, e.g libsas receive a
PORTE_BYTES_DMAED event, currently we process it as following steps:

sas_form_port  --- run in work in shost workq
	sas_discover_domain  --- run in another work in shost workq
		...
		sas_probe_devices  --- run in new work in shost workq
We found during hot-add a device, libsas may need run several
works in same workqueue to add device in system, the process is
not atomic, it may interrupt by other sas event works, like
PHYE_LOSS_OF_SIGNAL.

This patch is preparation of execute libsas sas event in sync. We need
to use different workqueue to run sas event and disco event. Otherwise
the work will be blocked for waiting another chained work in the same
workqueue.

Signed-off-by: Yijing Wang 
CC: John Garry 
CC: Johannes Thumshirn 
CC: Ewan Milne 
CC: Christoph Hellwig 
CC: Tomas Henzl 
CC: Dan Williams 
Signed-off-by: Jason Yan 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Martin K. Petersen

scsi: libsas: make the event threshold configurable

2018-01-09T02:59:28+00:00

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: Hannes Reinecke 
Signed-off-by: Jason Yan 
CC: John Garry 
CC: Johannes Thumshirn 
CC: Ewan Milne 
CC: Christoph Hellwig 
CC: Tomas Henzl 
CC: Dan Williams 
Acked-by: John Garry  #for hisi_sas part
Reviewed-by: Hannes Reinecke 
Signed-off-by: Martin K. Petersen

scsi: libsas: shut down the PHY if events reached the threshold

2018-01-09T02:59:28+00:00

If the PHY burst too many events, we will alloc a lot of events for the
worker. This may leads to memory exhaustion.

Dan Williams suggested to shut down the PHY if the events reached the
threshold, because in this case the PHY may have gone into some
erroneous state. Users can re-enable the PHY by sysfs if they want.

We cannot use the fixed memory pool because if we run out of events, the
shut down event and loss of signal event will lost too. The events still
need to be allocated and processed in this case.

Suggested-by: Dan Williams 
Signed-off-by: Jason Yan 
CC: John Garry 
CC: Johannes Thumshirn 
CC: Ewan Milne 
CC: Christoph Hellwig 
CC: Tomas Henzl 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Martin K. Petersen

scsi: libsas: Use dynamic alloced work to avoid sas event lost

2018-01-09T02:59:28+00:00

Now libsas hotplug work is static, every sas event type has its own
static work, LLDD driver queues the hotplug work into shost->work_q.  If
LLDD driver burst posts lots hotplug events to libsas, the hotplug
events may pending in the workqueue like

shost->work_q
new work[PORTE_BYTES_DMAED] --> |[PHYE_LOSS_OF_SIGNAL][PORTE_BYTES_DMAED] -> processing
                                |<-------wait worker to process-------->|

In this case, a new PORTE_BYTES_DMAED event coming, libsas try to queue
it to shost->work_q, but this work is already pending, so it would be
lost. Finally, libsas delete the related sas port and sas devices, but
LLDD driver expect libsas add the sas port and devices(last sas event).

This patch use dynamic allocated work to avoid this issue.

Signed-off-by: Yijing Wang 
CC: John Garry 
CC: Johannes Thumshirn 
CC: Ewan Milne 
CC: Christoph Hellwig 
CC: Tomas Henzl 
CC: Dan Williams 
Reviewed-by: Hannes Reinecke 
Signed-off-by: Jason Yan 
Signed-off-by: Martin K. Petersen

scsi: libsas: align sata_device's rps_resp on a cacheline

2017-11-22T04:06:32+00:00

The rps_resp buffer in ata_device is a DMA target, but it isn't
explicitly cacheline aligned. Due to this, adjacent fields can be
overwritten with stale data from memory on non-coherent architectures.
As a result, the kernel is sometimes unable to communicate with an SATA
device behind a SAS expander.

Fix this by ensuring that the rps_resp buffer is cacheline aligned.

This issue is similar to that fixed by Commit 84bda12af31f93 ("libata:
align ap->sector_buf") and Commit 4ee34ea3a12396f35b26 ("libata: Align
ata_device's id on a cacheline").

Cc: stable@vger.kernel.org
Signed-off-by: Huacai Chen 
Signed-off-by: Christoph Hellwig 
Signed-off-by: Martin K. Petersen

Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi

2017-11-15T00:23:44+00:00

Pull SCSI updates from James Bottomley:
 "This is mostly updates of the usual suspects: lpfc, qla2xxx, hisi_sas,
  megaraid_sas, pm80xx, mpt3sas, be2iscsi, hpsa. and a host of minor
  updates.

  There's no major behaviour change or additions to the core in all of
  this, so the potential for regressions should be small (biggest
  potential being in the scsi error handler changes)"

* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (203 commits)
  scsi: lpfc: Fix hard lock up NMI in els timeout handling.
  scsi: mpt3sas: remove a stray KERN_INFO
  scsi: mpt3sas: cleanup _scsih_pcie_enumeration_event()
  scsi: aacraid: use timespec64 instead of timeval
  scsi: scsi_transport_fc: add 64GBIT and 128GBIT port speed definitions
  scsi: qla2xxx: Suppress a kernel complaint in qla_init_base_qpair()
  scsi: mpt3sas: fix dma_addr_t casts
  scsi: be2iscsi: Use kasprintf
  scsi: storvsc: Avoid excessive host scan on controller change
  scsi: lpfc: fix kzalloc-simple.cocci warnings
  scsi: mpt3sas: Update mpt3sas driver version.
  scsi: mpt3sas: Fix sparse warnings
  scsi: mpt3sas: Fix nvme drives checking for tlr.
  scsi: mpt3sas: NVMe drive support for BTDHMAPPING ioctl command and log info
  scsi: mpt3sas: Add-Task-management-debug-info-for-NVMe-drives.
  scsi: mpt3sas: scan and add nvme device after controller reset
  scsi: mpt3sas: Set NVMe device queue depth as 128
  scsi: mpt3sas: Handle NVMe PCIe device related events generated from firmware.
  scsi: mpt3sas: API's to remove nvme drive from sml
  scsi: mpt3sas: API 's to support NVMe drive addition to SML
  ...

scsi: sas: Convert timers to use timer_setup()

2017-11-01T18:43:47+00:00

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 
Cc: "James E.J. Bottomley" 
Cc: "Martin K. Petersen" 
Cc: Jack Wang 
Cc: lindar_liu@usish.com
Cc: Jens Axboe 
Cc: Hannes Reinecke 
Cc: Johannes Thumshirn 
Cc: Benjamin Block 
Cc: Baoyou Xie 
Cc: Wei Yongjun 
Cc: linux-scsi@vger.kernel.org
Signed-off-by: Kees Cook 
Reviewed-by: Martin K. Petersen 
Acked-by: John Garry  # for hisi_sas part
Tested-by: John Garry  # basic sanity test for hisi_sas
Reviewed-by: Jack Wang