scsi: libsas: Declare sas_discover_end_dev() static

sas_discover_end_dev() is defined and used only in sas_discover.c. Define
this function as static.

Signed-off-by: Damien Le Moal <dlemoal@kernel.org>
Link: https://lore.kernel.org/r/20230912230551.454357-4-dlemoal@kernel.org
Reviewed-by: John Garry <john.g.garry@oracle.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

ata,scsi: remove ata_sas_port_destroy()

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

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

scsi: libsas: Delete struct scsi_core

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

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

scsi: libsas: Abort all in-flight requests when device is gone

When a disk is removed with in-flight I/O, the application needs to wait
for 30 seconds (depending on the timeout configuration) to hear back from
the kernel. Xingui tried to fix this issue by aborting the ATA link for
SATA devices[1], however this approach left the SAS devices unresolved.

Try to fix this issue by aborting all in-flight requests when the device is
gone. This is implemented by iterating over the tagset.

[1] https://lore.kernel.org/lkml/234e04db-7539-07e4-a6b8-c6b05f78193d@opensource.wdc.com/T/

Cc: Xingui Yang <yangxingui@huawei.com>
Cc: John Garry <john.g.garry@oracle.com>
Cc: Damien Le Moal <damien.lemoal@opensource.wdc.com>
Cc: Hannes Reinecke <hare@suse.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Link: https://lore.kernel.org/r/20230330110930.175539-1-yanaijie@huawei.com
Reviewed-by: John Garry <john.g.garry@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Change the coding style of sas_discover_sata()

The coding style where calling this interface is inconsistent with other
interfaces for SATA devices. The standard style for other SATA interfaces
is like:

#ifdefine CONFIG_SCSI_SAS_ATA
void sas_ata_task_abort(struct sas_task *task);
#else
static inline void sas_ata_task_abort(struct sas_task *task)
{
}
#endif

And the callers does not have to do things like "#ifdefine CONFIG_SCSI_SAS_ATA"
and may call the interface directly. So follow the standard style here.

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

scsi: libsas: Use void for sas_discover_event() return code

The callers of function sas_discover_event() do not check its return value.
The function also only ever returns 0, so use void instead.

Link: https://lore.kernel.org/r/1644561778-183074-2-git-send-email-chenxiang66@hisilicon.com
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Xiang Chen <chenxiang66@hisilicon.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: Remove superfluous #include <linux/async.h> directives

Remove this include directive from code that does not use any functionality
from kernel/async.c.

Link: https://lore.kernel.org/r/20211129194609.3466071-13-bvanassche@acm.org
Reviewed-by: Daejun Park <daejun7.park@samsung.com>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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

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

Link: https://lore.kernel.org/r/20210716074551.771312-1-yanaijie@huawei.com
Cc: John Garry <john.garry@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: Fix fall-through warning for Clang

Fix the following fallthrough warning (arm64-randconfig with Clang):

drivers/scsi/libsas/sas_discover.c:467:2: warning: unannotated fall-through between switch labels [-Wimplicit-fallthrough]

Reported-by: kernel test robot <lkp@intel.com>
Link: https://lore.kernel.org/lkml/60edca25.k00ut905IFBjPyt5%25lkp@intel.com/
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

scsi: libsas: Clean up whitespace

checkpatch reported several whitespace errors. Fix them all.

Link: https://lore.kernel.org/r/1616675396-6108-3-git-send-email-luojiaxing@huawei.com
Signed-off-by: Luo Jiaxing <luojiaxing@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

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

Simplify the return expression.

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

scsi: libsas: Fix error path in sas_notify_lldd_dev_found()

In sas_notify_lldd_dev_found(), if we can't allocate the necessary
resources, then it seems like the wrong thing to mark the device as found
and to increment the reference count. None of the callers ever drop the
reference in that situation.

[mkp: tweaked commit desc based on feedback from John]

Link: https://lore.kernel.org/r/20200905125836.GF183976@mwanda
Fixes: 735f7d2fedf5 ("[SCSI] libsas: fix domain_device leak")
Reviewed-by: Jason Yan <yanaijie@huawei.com>
Acked-by: John Garry <john.garry@huawei.com>
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

treewide: Use fallthrough pseudo-keyword

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

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

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

scsi: libsas: Tidy SAS address print format

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

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

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

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

Link: https://lore.kernel.org/r/1576758957-227350-1-git-send-email-john.garry@huawei.com
Signed-off-by: John Garry <john.garry@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: stop discovering if oob mode is disconnected

The discovering of sas port is driven by workqueue in libsas. When libsas
is processing port events or phy events in workqueue, new events may rise
up and change the state of some structures such as asd_sas_phy. This may
cause some problems such as follows:

==>thread 1 ==>thread 2

==>phy up
==>phy_up_v3_hw()
==>oob_mode = SATA_OOB_MODE;
==>phy down quickly
==>hisi_sas_phy_down()
==>sas_ha->notify_phy_event()
==>sas_phy_disconnected()
==>oob_mode = OOB_NOT_CONNECTED
==>workqueue wakeup
==>sas_form_port()
==>sas_discover_domain()
==>sas_get_port_device()
==>oob_mode is OOB_NOT_CONNECTED and device
is wrongly taken as expander

This at last lead to the panic when libsas trying to issue a command to
discover the device.

[183047.614035] Unable to handle kernel NULL pointer dereference at
virtual address 0000000000000058
[183047.622896] Mem abort info:
[183047.625762] ESR = 0x96000004
[183047.628893] Exception class = DABT (current EL), IL = 32 bits
[183047.634888] SET = 0, FnV = 0
[183047.638015] EA = 0, S1PTW = 0
[183047.641232] Data abort info:
[183047.644189] ISV = 0, ISS = 0x00000004
[183047.648100] CM = 0, WnR = 0
[183047.651145] user pgtable: 4k pages, 48-bit VAs, pgdp =
00000000b7df67be
[183047.657834] [0000000000000058] pgd=0000000000000000
[183047.662789] Internal error: Oops: 96000004 [#1] SMP
[183047.667740] Process kworker/u16:2 (pid: 31291, stack limit =
0x00000000417c4974)
[183047.675208] CPU: 0 PID: 3291 Comm: kworker/u16:2 Tainted: G
W OE 4.19.36-vhulk1907.1.0.h410.eulerosv2r8.aarch64 #1
[183047.687015] Hardware name: N/A N/A/Kunpeng Desktop Board D920S10,
BIOS 0.15 10/22/2019
[183047.695007] Workqueue: 0000:74:02.0_disco_q sas_discover_domain
[183047.700999] pstate: 20c00009 (nzCv daif +PAN +UAO)
[183047.705864] pc : prep_ata_v3_hw+0xf8/0x230 [hisi_sas_v3_hw]
[183047.711510] lr : prep_ata_v3_hw+0xb0/0x230 [hisi_sas_v3_hw]
[183047.717153] sp : ffff00000f28ba60
[183047.720541] x29: ffff00000f28ba60 x28: ffff8026852d7228
[183047.725925] x27: ffff8027dba3e0a8 x26: ffff8027c05fc200
[183047.731310] x25: 0000000000000000 x24: ffff8026bafa8dc0
[183047.736695] x23: ffff8027c05fc218 x22: ffff8026852d7228
[183047.742079] x21: ffff80007c2f2940 x20: ffff8027c05fc200
[183047.747464] x19: 0000000000f80800 x18: 0000000000000010
[183047.752848] x17: 0000000000000000 x16: 0000000000000000
[183047.758232] x15: ffff000089a5a4ff x14: 0000000000000005
[183047.763617] x13: ffff000009a5a50e x12: ffff8026bafa1e20
[183047.769001] x11: ffff0000087453b8 x10: ffff00000f28b870
[183047.774385] x9 : 0000000000000000 x8 : ffff80007e58f9b0
[183047.779770] x7 : 0000000000000000 x6 : 000000000000003f
[183047.785154] x5 : 0000000000000040 x4 : ffffffffffffffe0
[183047.790538] x3 : 00000000000000f8 x2 : 0000000002000007
[183047.795922] x1 : 0000000000000008 x0 : 0000000000000000
[183047.801307] Call trace:
[183047.803827] prep_ata_v3_hw+0xf8/0x230 [hisi_sas_v3_hw]
[183047.809127] hisi_sas_task_prep+0x750/0x888 [hisi_sas_main]
[183047.814773] hisi_sas_task_exec.isra.7+0x88/0x1f0 [hisi_sas_main]
[183047.820939] hisi_sas_queue_command+0x28/0x38 [hisi_sas_main]
[183047.826757] smp_execute_task_sg+0xec/0x218
[183047.831013] smp_execute_task+0x74/0xa0
[183047.834921] sas_discover_expander.part.7+0x9c/0x5f8
[183047.839959] sas_discover_root_expander+0x90/0x160
[183047.844822] sas_discover_domain+0x1b8/0x1e8
[183047.849164] process_one_work+0x1b4/0x3f8
[183047.853246] worker_thread+0x54/0x470
[183047.856981] kthread+0x134/0x138
[183047.860283] ret_from_fork+0x10/0x18
[183047.863931] Code: f9407a80 528000e2 39409281 72a04002 (b9405800)
[183047.870097] kernel fault(0x1) notification starting on CPU 0
[183047.875828] kernel fault(0x1) notification finished on CPU 0
[183047.881559] Modules linked in: unibsp(OE) hns3(OE) hclge(OE)
hnae3(OE) mem_drv(OE) hisi_sas_v3_hw(OE) hisi_sas_main(OE)
[183047.892418] ---[ end trace 4cc26083fc11b783 ]---
[183047.897107] Kernel panic - not syncing: Fatal exception
[183047.902403] kernel fault(0x5) notification starting on CPU 0
[183047.908134] kernel fault(0x5) notification finished on CPU 0
[183047.913865] SMP: stopping secondary CPUs
[183047.917861] Kernel Offset: disabled
[183047.921422] CPU features: 0x2,a2a00a38
[183047.925243] Memory Limit: none
[183047.928372] kernel reboot(0x2) notification starting on CPU 0
[183047.934190] kernel reboot(0x2) notification finished on CPU 0
[183047.940008] ---[ end Kernel panic - not syncing: Fatal exception
]---

Fixes: 2908d778ab3e ("[SCSI] aic94xx: new driver")
Link: https://lore.kernel.org/r/20191206011118.46909-1-yanaijie@huawei.com
Reported-by: Gao Chuan <gaochuan4@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

scsi: libsas: sas_discover: Mark expected switch fall-through

Mark switch cases where we are expecting to fall through.

Fix the following warning (Building: mtx1_defconfig mips):

drivers/scsi/libsas/sas_discover.c: In function ‘sas_discover_domain’:
./include/linux/printk.h:309:2: warning: this statement may fall through [-Wimplicit-fallthrough=]
printk(KERN_NOTICE pr_fmt(fmt), ##__VA_ARGS__)
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/scsi/libsas/sas_discover.c:459:3: note: in expansion of macro ‘pr_notice’
pr_notice("ATA device seen but CONFIG_SCSI_SAS_ATA=N so cannot attach\n");
^~~~~~~~~
drivers/scsi/libsas/sas_discover.c:462:2: note: here
default:
^~~~~~~

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>

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

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

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

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

scsi: libsas: switch remaining files to SPDX tags

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

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

scsi: libsas: Remove pcidev reference

Not all host drivers are PCI drivers - like hisi_sas, which supports a
platform driver - so remove reference to "pcidev".

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

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

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

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

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

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

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

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

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

scsi: libsas: make the lldd_port_deformed method optional

Now LLDDs have to implement lldd_port_deformed method otherwise NULL
dereference will happen. Make it optional and remove the dummy implementation
in hisi_sas.

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

scsi: libsas: dynamically allocate and free ata host

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

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

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

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

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

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

scsi: libsas: add transport class for ATA devices

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

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

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

ata_link:
link1 link2

ata_port:
ata1 ata2

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

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

scsi: libsas: Fix kernel-doc headers

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

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

scsi: libsas: direct call probe and destruct

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

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

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

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

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

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

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

[mkp: kbuild test robot warning]

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

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

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

libsas: Fix Kernel Crash in smp_execute_task

This crash was reported:

[ 366.947370] sd 3:0:1:0: [sdb] Spinning up disk....
[ 368.804046] BUG: unable to handle kernel NULL pointer dereference at (null)
[ 368.804072] IP: [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[ 368.804098] PGD 0
[ 368.804114] Oops: 0002 [#1] SMP
[ 368.804143] CPU 1
[ 368.804151] Modules linked in: sg netconsole s3g(PO) uinput joydev hid_multitouch usbhid hid snd_hda_codec_via cpufreq_userspace cpufreq_powersave cpufreq_stats uhci_hcd cpufreq_conservative snd_hda_intel snd_hda_codec snd_hwdep snd_pcm sdhci_pci snd_page_alloc sdhci snd_timer snd psmouse evdev serio_raw pcspkr soundcore xhci_hcd shpchp s3g_drm(O) mvsas mmc_core ahci libahci drm i2c_core acpi_cpufreq mperf video processor button thermal_sys dm_dmirror exfat_fs exfat_core dm_zcache dm_mod padlock_aes aes_generic padlock_sha iscsi_target_mod target_core_mod configfs sswipe libsas libata scsi_transport_sas picdev via_cputemp hwmon_vid fuse parport_pc ppdev lp parport autofs4 ext4 crc16 mbcache jbd2 sd_mod crc_t10dif usb_storage scsi_mod ehci_hcd usbcore usb_common
[ 368.804749]
[ 368.804764] Pid: 392, comm: kworker/u:3 Tainted: P W O 3.4.87-logicube-ng.22 #1 To be filled by O.E.M. To be filled by O.E.M./EPIA-M920
[ 368.804802] RIP: 0010:[<ffffffff81358457>] [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[ 368.804827] RSP: 0018:ffff880117001cc0 EFLAGS: 00010246
[ 368.804842] RAX: 0000000000000000 RBX: ffff8801185030d0 RCX: ffff88008edcb420
[ 368.804857] RDX: 0000000000000000 RSI: 0000000000000002 RDI: ffff8801185030d4
[ 368.804873] RBP: ffff8801181531c0 R08: 0000000000000020 R09: 00000000fffffffe
[ 368.804885] R10: 0000000000000000 R11: 0000000000000000 R12: ffff8801185030d4
[ 368.804899] R13: 0000000000000002 R14: ffff880117001fd8 R15: ffff8801185030d8
[ 368.804916] FS: 0000000000000000(0000) GS:ffff88011fc80000(0000) knlGS:0000000000000000
[ 368.804931] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
[ 368.804946] CR2: 0000000000000000 CR3: 000000000160b000 CR4: 00000000000006e0
[ 368.804962] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[ 368.804978] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
[ 368.804995] Process kworker/u:3 (pid: 392, threadinfo ffff880117000000, task ffff8801181531c0)
[ 368.805009] Stack:
[ 368.805017] ffff8801185030d8 0000000000000000 ffffffff8161ddf0 ffffffff81056f7c
[ 368.805062] 000000000000b503 ffff8801185030d0 ffff880118503000 0000000000000000
[ 368.805100] ffff8801185030d0 ffff8801188b8000 ffff88008edcb420 ffffffff813583ac
[ 368.805135] Call Trace:
[ 368.805153] [<ffffffff81056f7c>] ? up+0xb/0x33
[ 368.805168] [<ffffffff813583ac>] ? mutex_lock+0x16/0x25
[ 368.805194] [<ffffffffa018c414>] ? smp_execute_task+0x4e/0x222 [libsas]
[ 368.805217] [<ffffffffa018ce1c>] ? sas_find_bcast_dev+0x3c/0x15d [libsas]
[ 368.805240] [<ffffffffa018ce4f>] ? sas_find_bcast_dev+0x6f/0x15d [libsas]
[ 368.805264] [<ffffffffa018e989>] ? sas_ex_revalidate_domain+0x37/0x2ec [libsas]
[ 368.805280] [<ffffffff81355a2a>] ? printk+0x43/0x48
[ 368.805296] [<ffffffff81359a65>] ? _raw_spin_unlock_irqrestore+0xc/0xd
[ 368.805318] [<ffffffffa018b767>] ? sas_revalidate_domain+0x85/0xb6 [libsas]
[ 368.805336] [<ffffffff8104e5d9>] ? process_one_work+0x151/0x27c
[ 368.805351] [<ffffffff8104f6cd>] ? worker_thread+0xbb/0x152
[ 368.805366] [<ffffffff8104f612>] ? manage_workers.isra.29+0x163/0x163
[ 368.805382] [<ffffffff81052c4e>] ? kthread+0x79/0x81
[ 368.805399] [<ffffffff8135fea4>] ? kernel_thread_helper+0x4/0x10
[ 368.805416] [<ffffffff81052bd5>] ? kthread_flush_work_fn+0x9/0x9
[ 368.805431] [<ffffffff8135fea0>] ? gs_change+0x13/0x13
[ 368.805442] Code: 83 7d 30 63 7e 04 f3 90 eb ab 4c 8d 63 04 4c 8d 7b 08 4c 89 e7 e8 fa 15 00 00 48 8b 43 10 4c 89 3c 24 48 89 63 10 48 89 44 24 08 <48> 89 20 83 c8 ff 48 89 6c 24 10 87 03 ff c8 74 35 4d 89 ee 41
[ 368.805851] RIP [<ffffffff81358457>] __mutex_lock_common.isra.7+0x9c/0x15b
[ 368.805877] RSP <ffff880117001cc0>
[ 368.805886] CR2: 0000000000000000
[ 368.805899] ---[ end trace b720682065d8f4cc ]---

It's directly caused by 89d3cf6 [SCSI] libsas: add mutex for SMP task
execution, but shows a deeper cause: expander functions expect to be able to
cast to and treat domain devices as expanders. The correct fix is to only do
expander discover when we know we've got an expander device to avoid wrongly
casting a non-expander device.

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

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

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

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

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

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

[SCSI] libsas: suspend / resume support

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

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

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

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

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

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

[SCSI] libsas: drop sata port multiplier infrastructure

On the way to add a new sata_device field, noticed that libsas is
carrying port multiplier infrastructure that is explicitly disabled by
sas_discover_sata(). The aic94xx touches the unused port_no, so leave
that field in case there was some use for it.

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

[SCSI] libsas: enforce eh strategy handlers only in eh context

The strategy handlers may be called in places that are problematic for
libsas (i.e. sata resets outside of domain revalidation filtering /
libata link recovery), or problematic for userspace (non-blocking ioctl
to sleeping reset functions). However, these routines are also called
for eh escalations and recovery of scsi_eh_prep_cmnd(), so permit them
as long as we are running in the host's error handler, otherwise arrange
for them to be triggered in eh_context.

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

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

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

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

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

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

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

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

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

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

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

[SCSI] libsas: unify domain_device sas_rphy lifetimes

Since the domain_device can out live the scsi_target we need the rphy to
follow suit otherwise we run into issues like:

BUG: unable to handle kernel NULL pointer dereference at 0000000000000050
IP: [<ffffffffa011561b>] sas_ata_printk+0x43/0x6f [libsas]
PGD 0
Oops: 0000 [#1] SMP
CPU 1
Modules linked in: ses enclosure isci libsas scsi_transport_sas fuse sunrpc cpufreq_ondemand acpi_cpufreq freq_table mperf microcode pcspkr igb joydev iTCO_wdt ioatdma iTCO_vendor_support i2c_i801 i2c_core dca wmi hed ipv6 pata_acpi ata_generic [last unloaded: scsi_wait_scan]

Pid: 129, comm: kworker/u:3 Not tainted 3.3.0-rc5-isci+ #1 Intel Corporation SandyBridge Platform/To be filled by O.E.M.
RIP: 0010:[<ffffffffa011561b>] [<ffffffffa011561b>] sas_ata_printk+0x43/0x6f [libsas]
RSP: 0018:ffff88042232dd70 EFLAGS: 00010282
RAX: 0000000000000000 RBX: ffff8804283165b8 RCX: ffff88042232dda0
RDX: ffff88042232dd78 RSI: ffff8804283165b8 RDI: ffffffffa01188d7
RBP: ffff88042232ddd0 R08: ffff880388454000 R09: ffff8803edfde1f8
R10: ffff8803edfde1f8 R11: ffff8803edfde1f8 R12: ffff880428316750
R13: ffff880388454000 R14: ffff8803f88b31d0 R15: ffff8803f8b21d50
FS: 0000000000000000(0000) GS:ffff88042ee20000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: 0000000000000050 CR3: 0000000001a05000 CR4: 00000000000406e0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Process kworker/u:3 (pid: 129, threadinfo ffff88042232c000, task ffff88042230c920)
Stack:
0000000000000000 ffff880400000018 ffff88042232dde0 ffff88042232dda0
ffffffffa01188c4 ffff88042ee93af0 ffff88042232ddb0 ffffffff8100e047
ffff88042232de10 ffff880420e5a2c8 ffff8803f8b21d50 ffff8803edfde1f8
Call Trace:
[<ffffffff8100e047>] ? load_TLS+0xb/0xf
[<ffffffffa01156ad>] async_sas_ata_eh+0x66/0x95 [libsas]
[<ffffffff810655e1>] async_run_entry_fn+0x9e/0x131

Reported-by: Tom Jackson <thomas.p.jackson@intel.com>
Tested-by: Tom Jackson <thomas.p.jackson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: fix sas_get_port_device regression

Commit 899fcf4 "[SCSI] libsas: set attached device type and target
protocols for local phys" setup 'phy' to be dereferenced after
list_for_each_entry(phy, &port->phy_list, port_phy_el) (i.e. phy ==
&port->phy_list) resulting in reports like:

BUG: unable to handle kernel NULL pointer dereference at 00000000000002b0
IP: [<ffffffffa00ce948>] sas_discover_domain+0x29e/0x4fb [libsas]

...fix by deferring sas_phy_set_target() to the end of
sas_get_port_device().

Reported-by: Tom Jackson <thomas.p.jackson@intel.com>
Tested-by: Tom Jackson <thomas.p.jackson@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: introduce sas_work to fix sas_drain_work vs sas_queue_work

When requeuing work to a draining workqueue the last work instance may
not be idle, so sas_queue_work() must not touch work->entry. Introduce
sas_work with a drain_node list_head to have a private list for
collecting work deferred due to drain collision.

Fixes reports like:
BUG: unable to handle kernel NULL pointer dereference at (null)
IP: [<ffffffff810410d4>] process_one_work+0x2e/0x338

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

[SCSI] libsas: set attached device type and target protocols for local phys

Before:
$ cat /sys/class/sas_phy/phy-6\:3/device_type
none
$ cat /sys/class/sas_phy/phy-6\:3/target_port_protocols
none

After:
$ cat /sys/class/sas_phy/phy-6\:3/device_type
end device
$ cat /sys/class/sas_phy/phy-6\:3/target_port_protocols
sata

Also downgrade the phy_list_lock to _irq instead of _irqsave since
libsas will never call sas_get_port_device with interrupts disbled.

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

[SCSI] libsas: async ata scanning

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

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

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

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

[SCSI] libsas: restore scan order

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

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

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

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

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

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

[SCSI] libsas: kill spurious sas_put_device

Holdover from a patch rework, prior to the addition of SAS_DEV_DESTROY
we were holding a reference while the destruct was pending in case the
domain was torn down before the desctruct event ran. That case is
covered by SAS_DEV_DESTROY, and the sas_put_device() just corrupts freed
memory, or worse frees the memory while another agent holds a reference.

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

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

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

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

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

Reported-by: Marcin Tomczak <marcin.tomczak@intel.com>
Acked-by: Jeff Garzik <jgarzik@redhat.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

[SCSI] libsas: mark all domain devices gone if root port disappears

If the top level expander is hot removed, mark all child devices as gone
before unregistration to short circuit futile recovery.

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

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

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

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

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

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

[SCSI] libsas: add mutex for SMP task execution

SAS does not tag SMP requests, and at least one lldd (isci) does not permit
more than one in-flight request at a time.

[jejb: fix sas_init_dev tab issues while we're at it]
Signed-off-by: Jeff Skirvin <jeffrey.d.skirvin@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>

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

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

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

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

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

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

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

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

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

[SCSI] libsas: introduce sas_drain_work()

When an lldd invokes ->notify_port_event() it can trigger a chain of libsas
events to:

1/ form the port and find the direct attached device

2/ if the attached device is an expander perform domain discovery

A call to flush_workqueue() will only flush the initial port formation work.
Currently libsas users need to call scsi_flush_work() up to the max depth of
chain (which will grow from 2 to 3 when ata discovery is moved to its own
discovery event). Instead of open coding multiple calls switch to use
drain_workqueue() to flush sas work.

drain_workqueue() does not handle new work submitted during the drain so
libsas needs a bit of infrastructure to hold off unchained work submissions
while a drain is in flight. A lldd ->notify() event is considered 'unchained'
while a sas_discover_event() is 'chained'. As Tejun notes:

"For now, I think it would be best to add private wrapper in libsas to
support deferring unchained work items while draining."

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

[SCSI] libsas: replace event locks with atomic bitops

The locks only served to make sure the pending event bitmask was updated
consistently.

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

[SCSI] libsas: fix leak of dev->sata_dev.identify_[packet_]device

These are never freed in the nominal path. A domain_device has a
different lifetime than a sas_rphy we need a dev->rphy independent way
of identifying sata devices.

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

[SCSI] libsas: fix domain_device leak

Arrange for the deallocation of a struct domain_device object when it no
longer has:
1/ any children
2/ references by any scsi_targets
3/ references by a lldd

The comment about domain_device lifetime in
Documentation/scsi/libsas.txt is stale as it appears mainline never had
a version of a struct domain_device that was registered as a kobject.
We now manage domain_device reference counts on behalf of external
agents.

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

[SCSI] libsas: fix port->dev_list locking

port->dev_list maintains a list of devices attached to a given sas root port.
It needs to be mutated under a lock as contexts outside of the
single-threaded-libsas-workqueue access the list via sas_find_dev_by_rphy().
Fixup locations where the list was being mutated without a lock.

This is a follow-up to commit 5911e963 "[SCSI] libsas: remove expander
from dev list on error", where Luben noted [1]:

> 2/ We have unlocked list manipulations in sas_ex_discover_end_dev(),
> sas_unregister_common_dev(), and sas_ex_discover_end_dev()

Yes, I can see that and that is very unfortunate.

[1]: http://marc.info/?l=linux-scsi&m=131480962006471&w=2

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

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

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

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

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

The script does the followings.

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

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

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

The conversion was done in the following steps.

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

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

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

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

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

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

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

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

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

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

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

[SCSI] struct device - replace bus_id with dev_name(), dev_set_name()

[jejb: limit ioctl to returning 20 characters to avoid overrun
on long device names and add a few more conversions]
Signed-off-by: Kay Sievers <kay.sievers@vrfy.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>

[SCSI] libsas: Warn if ATA device detected but CONFIG_SCSI_SAS_ATA not set

We give a very cryptic error if an ATA device is seen on a SAS port
but libsas isn't compiled to include libata to handle them. Add an
extra warning to explain specifically what the problem is.

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

[SCSI] libsas: Convert sas_proto users to sas_protocol

sparse complains about the mixing of enums in libsas. Since the
underlying numeric values of both enums are the same, combine them
to get rid of the warning.

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

Use helpers to obtain task pid in printks

The task_struct->pid member is going to be deprecated, so start
using the helpers (task_pid_nr/task_pid_vnr/task_pid_nr_ns) in
the kernel.

The first thing to start with is the pid, printed to dmesg - in
this case we may safely use task_pid_nr(). Besides, printks produce
more (much more) than a half of all the explicit pid usage.

[akpm@linux-foundation.org: git-drm went and changed lots of stuff]
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Cc: Dave Airlie <airlied@linux.ie>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[SCSI] libsas: Remove PCI dependencies

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

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

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

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

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

[SCSI] libsas: fix lockdep issue with ATA

lockdep noticed that with ATA support the port->dev_list_lock was
entangled at irq context, so it now needs to become IRQ safe

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

[SCSI] libsas, aic94xx: fix dma mapping cockups with ATA

This one was noticed by Gilbert Wu of Adaptec:

The libata core actually does the DMA mapping for you, so there has to
be an exception in the device drivers that *don't* do dma mapping for
ATA commands. However, since we've already done this, libsas must now
dma map any ATA commands that it wishes to issue ... and yes, this is a
horrible mess.

Additionally, the test in aic94xx for ATA protocols isn't quite right.

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

[SCSI] libsas: fixup NCQ for SATA disks

We actually had two problems: the one with the tag (which is fixed by
zeroing the tag before sending the taskfile to the sequencer) but the
other with the fact that we sent our first NCQ command to the device
before the sequencer had been informed of the NCQ tagging
capabilities. I fixed the latter by moving the rphy_add() to the
correct point in the code after the NCQ capabilities are set up.

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

[SCSI] Add SATA support to libsas

Hook the scsi_host_template functions in libsas to delegate
functionality to libata when appropriate.

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

Misc code changes and merge fixes and update for libata->drivers/ata
move

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

[SCSI] libsas: Clean up discovery failure handler code

sas_rphy_delete does two things: it removes the sas_rphy from the transport
layer and frees the sas_rphy. This can be broken down into two functions,
sas_rphy_remove and sas_rphy_free; sas_rphy_remove is of interest to
sas_discover_root_expander because it calls functions that require
sas_rphy_add as a prerequisite and can fail (namely sas_discover_expander).
In that case, sas_discover_root_expander needs to be able to undo the effects
of sas_rphy_add yet leave the job of freeing the sas_rphy to the caller of
sas_discover_root_expander.

This patch also removes some unnecessary code from sas_discover_end_dev
to eliminate an unnecessary cycle of sas_notify_lldd_gone/found for SAS
devices, thus eliminating a sas_rphy_remove call (and fixing a race condition
where a SCSI target scan can come in between the gone and found call).
It also moves the sas_rphy_free calls into sas_discover_domain and
sas_ex_discover_end_dev to complement the sas_rphy_allocation via
sas_get_port_device.

This patch does not change the semantics of sas_rphy_delete.

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

[SCSI] libsas: Add SAS_HA state flags to avoid queueing events while unloading

Track sas_ha_struct state so that we ignore events that come in while
we're shutting things down.

Signed-off-by: Malahal Naineni <malahal@us.ibm.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>

[SCSI] libsas: Clean up rphys/port dev list after a discovery error.

sas_get_port_device assigns a rphy to a domain device in anticipation
of finding a disk. When a discovery error occurs in
sas_discover_{sata,sas,expander}*, however, we need to clean up that
rphy and the port device list so that we don't GPF. In addition, we
need to check the result of the second sas_notify_lldd_dev_found.
This patch seems ok on a x260, x366 and x206m.

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

WorkStruct: make allyesconfig

Fix up for make allyesconfig.

Signed-Off-By: David Howells <dhowells@redhat.com>

[SCSI] aic94xx: new driver

This is the end point of the separate aic94xx driver based on the
original driver and transport class from Luben Tuikov
<ltuikov@yahoo.com>

The log of the separate development is:

Alexis Bruemmer:
o aic94xx: fix hotplug/unplug for expanderless systems
o aic94xx: disable split completion timer/setting by default
o aic94xx: wide port off expander support
o aic94xx: remove various inline functions
o aic94xx: use bitops
o aic94xx: remove queue comment
o aic94xx: remove sas_common.c
o aic94xx: sas remove depot's
o aic94xx: use available list_for_each_entry_safe_reverse()
o aic94xx: sas header file merge

James Bottomley:
o aic94xx: fix TF_TMF_NO_CTX processing
o aic94xx: convert to request_firmware interface
o aic94xx: fix hotplug/unplug
o aic94xx: add link error counts to the expander phys
o aic94xx: add transport class phy reset capability
o aic94xx: remove local_attached flag
o Remove README
o Fixup Makefile variable for libsas rename
o Rename sas->libsas
o aic94xx: correct return code for sas_discover_event
o aic94xx: use parent backlink port
o aic94xx: remove channel abstraction
o aic94xx: fix routing algorithms
o aic94xx: add backlink port
o aic94xx: fix cascaded expander properties
o aic94xx: fix sleep under lock
o aic94xx: fix panic on module removal in complex topology
o aic94xx: make use of the new sas_port
o rename sas_port to asd_sas_port
o Fix for eh_strategy_handler move
o aic94xx: move entirely over to correct transport class formulation
o remove last vestages of sas_rphy_alloc()
o update for eh_timed_out move
o Preliminary expander support for aic94xx
o sas: remove event thread
o minor warning cleanups
o remove last vestiges of id mapping arrays
o Further updates
o Convert aic94xx over entirely to the transport class end device and
o update aic94xx/sas to use the new sas transport class end device
o [PATCH] aic94xx: attaching to the sas transport class
o Add missing completion removal from prior patch
o [PATCH] aic94xx: attaching to the sas transport class
o Build fixes from akpm

Jeff Garzik:
o [scsi aic94xx] Remove ->owner from PCI info table

Luben Tuikov:
o initial aic94xx driver

Mike Anderson:
o aic94xx: fix panic on module insertion
o aic94xx: stub out SATA_DEV case
o aic94xx: compile warning cleanups
o aic94xx: sas_alloc_task
o aic94xx: ref count update
o aic94xx nexus loss time value
o [PATCH] aic94xx: driver assertion in non-x86 BIOS env

Randy Dunlap:
o libsas: externs not needed

Robert Tarte:
o aic94xx: sequence patch - fixes SATA support

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