The timer and the completion are only used for slow path tasks (smp, and
lldd tmfs), yet we incur the allocation space and cpu setup time for
every fast path task.

Cc: Xiangliang Yu <yuxiangl@marvell.com>
Acked-by: NJack Wang <jack_wang@usish.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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

When recovering failed eh-cmnds let the lldd attempt an abort via
scsi_abort_eh_cmnd before escalating.
Reviewed-by: NJacek Danecki <jacek.danecki@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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

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: NJacek Danecki <jacek.danecki@intel.com>
Acked-by: NJeff Garzik <jgarzik@redhat.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Introduce scsi_dh_attached_handler_name() to retrieve the name of the
scsi_dh that is attached to the scsi_device associated with the provided
request queue.  Returns NULL if a scsi_dh is not attached.

Also, fix scsi_dh_{attach,detach} function header comments to document
@q rather than @sdev.
Signed-off-by: NMike Snitzer <snitzer@redhat.com>
Tested-by: NBabu Moger <babu.moger@netapp.com>
Reviewed-by: NChandra Seetharaman <sekharan@us.ibm.com>
Acked-by: NHannes Reinecke <hare@suse.de>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

During alua transitions, an array can return transitioning
status in response to rtpg requests.  These requests get
retried for a maximum of 60 seconds by default before timing
out.  Sometimes this timeout isn't sufficient to allow the
array to complete the transition.  T10-spc4 addresses this
under 'Report Target Port Groups' command.

This update retrieves the timeout value from the storage
array if available and retries the transitioning rtpgs
for up to the 'implied transitioning timeout' value
Signed-off-by: NRob Evers <revers@redhat.com>
Reviewed-by: NBabu Moger <babu.moger@netapp.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This has scsi_internal_device_unblock/scsi_target_unblock take
the new state to set the devices as an argument instead of
always setting to running. The patch also converts users of these
functions.

This allows the FC and iSCSI class to transition devices from blocked
to transport-offline, so that when fast_io_fail/replacement_timeout
has fired we do not set the devices back to running. Instead, we
set them to SDEV_TRANSPORT_OFFLINE.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This patch adds a new state SDEV_TRANSPORT_OFFLINE. It will
be used by transport classes to offline devices for cases like
when the fast_io_fail/recovery_tmo fires. In those cases we
want all IO to fail, and we have not yet escalated to dev_loss_tmo
behavior where we are removing the devices.

Currently to handle this state, transport classes are setting
the scsi_device's state to running, setting their internal
session/port structs state to something that indicates failed,
and then failing IO from some transport check in the queuecommand.

The reason for the new value is so that users can distinguish
between a device failure that is a result of a transport problem
vs the wide range of errors that devices get offlined for
when a scsi command times out and we offline the devices there.
It also fixes the confusion as to why the transport class is
failing IO, but has set the device state from blocked to running.
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Updates newly added stats from fc_get_host_stats,
added new function fc_exch_update_stats to
update exches related stats from fc_exch.c
by going thru internal ema_list elements.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Acked-by : Robert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Adds stats to track FCP pkt and frame alloc
failure.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Acked-by : Robert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The libfc is used by fcoe but fcoe agnostic,
and therefore should not have any fcoe references.

So renaming fcoe_dev_stats from libfc as its for fc_stats.
After that libfc is fcoe string free except some strings for
Open-FCoE.org.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Acked-by : Robert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Acked-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

The libfc provides more flexibility and with that
we can monitor some more FC specific stats for
FC exches or FCP error cases, this patch add
such new FC stats.

The patch adds *only* FC specific new stats to
existing fc_host attribute container.

Added stats names are self explanatory as
existing FC stats already has, however anyway
still added commentary along their definition
to describe them.
Signed-off-by: NVasu Dev <vasu.dev@intel.com>
Acked-by : Robert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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

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

Avoid crashing if the private_data pointer happens to be NULL. This has
been seen sometimes when a host reset happens, notably when there are
many LUNs:

host3: Assigned Port ID 0c1601
scsi host3: libfc: Host reset succeeded on port (0c1601)
BUG: unable to handle kernel NULL pointer dereference at 0000000000000350
IP: [<ffffffff81352bb8>] scsi_send_eh_cmnd+0x58/0x3a0
<snip>
Process scsi_eh_3 (pid: 4144, threadinfo ffff88030920c000, task ffff880326b160c0)
Stack:
 000000010372e6ba 0000000000000282 000027100920dca0 ffffffffa0038ee0
 0000000000000000 0000000000030003 ffff88030920dc80 ffff88030920dc80
 00000002000e0000 0000000a00004000 ffff8803242f7760 ffff88031326ed80
Call Trace:
 [<ffffffff8105b590>] ? lock_timer_base+0x70/0x70
 [<ffffffff81352fbe>] scsi_eh_tur+0x3e/0xc0
 [<ffffffff81353a36>] scsi_eh_test_devices+0x76/0x170
 [<ffffffff81354125>] scsi_eh_host_reset+0x85/0x160
 [<ffffffff81354291>] scsi_eh_ready_devs+0x91/0x110
 [<ffffffff813543fd>] scsi_unjam_host+0xed/0x1f0
 [<ffffffff813546a8>] scsi_error_handler+0x1a8/0x200
 [<ffffffff81354500>] ? scsi_unjam_host+0x1f0/0x1f0
 [<ffffffff8106ec3e>] kthread+0x9e/0xb0
 [<ffffffff81509264>] kernel_thread_helper+0x4/0x10
 [<ffffffff8106eba0>] ? kthread_freezable_should_stop+0x70/0x70
 [<ffffffff81509260>] ? gs_change+0x13/0x13
Code: 25 28 00 00 00 48 89 45 c8 31 c0 48 8b 87 80 00 00 00 48 8d b5 60 ff ff ff 89 d1 48 89 fb 41 89 d6 4c 89 fa 48 8b 80 b8 00 00 00
 <48> 8b 80 50 03 00 00 48 8b 00 48 89 85 38 ff ff ff 48 8b 07 4c
RIP  [<ffffffff81352bb8>] scsi_send_eh_cmnd+0x58/0x3a0
 RSP <ffff88030920dc50>
CR2: 0000000000000350
Signed-off-by: NMark Rustad <mark.d.rustad@intel.com>
Tested-by: NMarcus Dennis <marcusx.e.dennis@intel.com>
Cc: <stable@kernel.org>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Several bug reports have been received recently for USB mass-storage
devices that don't handle READ CAPACITY(16) commands properly.  They
report bogus sizes, in some cases becoming unusable as a result.

The bugs were triggered by commit
09b6b51b (SCSI & usb-storage: add
flags for VPD pages and REPORT LUNS), which caused usb-storage to stop
overriding the SCSI level reported by devices.  By default, the sd
driver will try READ CAPACITY(16) first for any device whose level is
above SCSI_SPC_2.

It seems likely that any device large enough to require the use of
READ CAPACITY(16) (i.e., 2 TB or more) would be able to handle READ
CAPACITY(10) commands properly.  Indeed, I don't know of any devices
that don't handle READ CAPACITY(10) properly.

Therefore this patch (as1559) adds a new flag telling the sd driver
to try READ CAPACITY(10) before READ CAPACITY(16), and sets this flag
for every USB mass-storage device.  If a device really is larger than
2 TB, sd will fall back to READ CAPACITY(16) just as it used to.

This fixes Bugzilla #43391.
Signed-off-by: NAlan Stern <stern@rowland.harvard.edu>
Acked-by: NHans de Goede <hdegoede@redhat.com>
CC: "James E.J. Bottomley" <JBottomley@parallels.com>
CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net>
Cc: stable <stable@vger.kernel.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

This patch has the SW FCoE driver and the bnx2fc
driver make use of the new fcoe_sysfs API added
earlier in this patch series.

After this patch a fcoe_ctlr_device is allocated with
private data in this order.

+------------------+   +------------------+
| fcoe_ctlr_device |   | fcoe_ctlr_device |
+------------------+   +------------------+
| fcoe_ctlr        |   | fcoe_ctlr        |
+------------------+   +------------------+
| fcoe_interface   |   | bnx2fc_interface |
+------------------+   +------------------+

libfcoe also takes part in this new model since it
discovers and manages fcoe_fcf instances. The memory
allocation is different for FCFs. I didn't want to
impact libfcoe's fcoe_fcf processing, so this patch
creates fcoe_fcf_device instances for each discovered
fcoe_fcf. The two are paired using a (void * priv)
member of the fcoe_ctlr_device. This allows libfcoe
to continue maintaining its list of fcoe_fcf instances
and simply attaches and detaches them from existing
or new fcoe_fcf_device instances.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This patch adds a 'fcoe bus' infrastructure to the kernel
that is driven by changes to libfcoe which allow LLDs to
present FIP (FCoE Initialization Protocol) discovered
entities and their attributes to user space via sysfs.

This patch adds the following APIs-

fcoe_ctlr_device_add
fcoe_ctlr_device_delete
fcoe_fcf_device_add
fcoe_fcf_device_delete

They allow the LLD to expose the FCoE ENode Controller
and any discovered FCFs (Fibre Channel Forwarders, e.g.
FCoE switches) to the user. Each of these new devices
has their own bus_type so that they are grouped together
for easy lookup from a user space application. Each
new class has an attribute_group to expose attributes
for any created instances. The attributes are-

fcoe_ctlr_device
* fcf_dev_loss_tmo
* lesb_link_fail
* lesb_vlink_fail
* lesb_miss_fka
* lesb_symb_err
* lesb_err_block
* lesb_fcs_error

fcoe_fcf_device
* fabric_name
* switch_name
* priority
* selected
* fc_map
* vfid
* mac
* fka_peroid
* fabric_state
* dev_loss_tmo

A device loss infrastructre similar to the FC Transport's
is also added by this patch. It is nice to have so that a
link flapping adapter doesn't continually advance the count
used to identify the discovered FCF. FCFs will exist in a
"Disconnected" state until either the timer expires or the
FCF is rediscovered and becomes "Connected."

This patch generates a few checkpatch.pl WARNINGS that
I'm not sure what to do about. They're macros modeled
around the FC Transport attribute building macros, which
have the same 'feature' where the caller can ommit a cast
in the argument list and no cast occurs in the code. I'm
not sure how to keep the code condensed while keeping the
macros. Any advice would be appreciated.
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Acked-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Currently the fcoe_ctlr associated with an interface is allocated
as a member of struct fcoe_interface. This causes problems when
attempting to use the new fcoe_sysfs APIs which allow us to allocate
the fcoe_interface as private data to the fcoe_ctlr_device instance.
The problem is that libfcoe wants to be able use pointer math to find a
fcoe_ctlr's fcoe_ctlr_device as well as finding a fcoe_ctlr_device's
assocated fcoe_ctlr. To do this we need to allocate the
fcoe_ctlr_device, with private data for the LLD. The private data
contains the fcoe_ctlr and its private data is the fcoe_interface.
This patch only allocates the fcoe_interface with the fcoe_ctlr, the
fcoe_ctlr_device will be added in a later patch, which will complete
the below diagram-

+------------------+
| fcoe_ctlr_device |
+------------------+
| fcoe_ctlr        |
+------------------+
| fcoe_interface   |
+------------------+

This prep work will allow us to go from a fcoe_ctlr_device instance
to its fcoe_ctlr as well as from a fcoe_ctlr to its fcoe_ctlr_device
once the fcoe_sysfs API is in use (later patches in this series).
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Tested-by: NRoss Brattain <ross.b.brattain@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Holdovers from the initial driver cleanup, replace with enum sas_protocol.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>

Implement the ISCSI_HOST_PARAM_INITIATOR_NAME for .get_host_param
Signed-off-by: NJohn Soni Jose <sony.john-n@emulex.com>
Signed-off-by: NJayamohan Kallickal <jayamohan.kallickal@emulex.com>
Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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: NMichal Kosciowski <michal.kosciowski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Acked-by: NJeff Garzik <jgarzik@redhat.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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

Commit 18a4d0a2 ("[SCSI] Handle disk devices which can not process
medium access commands") introduced a bug in which we would attempt to
dereference the scsi driver even when the device had no ULD attached.

Ensure that a driver is registered and make the driver accessor function
more resilient to errors during device discovery.
Reported-by: NElric Fu <elricfu1@gmail.com>
Reported-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

Some switch implementations (eg., HP virtual connect FlexFabric) send two MAC
descriptors in FIP FLOGI response, with first MAC descriptor (granted_mac) used
as FPMA, and the second one (fcoe_mac) used as destination address for
sending/receiving FCoE packets. fip_mac continues to be used for FIP traffic.
This patch introduces fcoe_mac in fcoe_fcf structure. For regular switches,
both fcoe_mac and fip_mac will be the same. For the switches that send
additional MAC descriptor, fcoe_mac is updated.
Signed-off-by: NBhanu Prakash Gollapudi <bprakash@broadcom.com>
Signed-off-by: NRobert Love <robert.w.love@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

We don't need to pack 'struct iscsi_chap_rec' as buffer is built
locally in the driver and pass to the user-space.
Signed-off-by: NVikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

Defined error codes for ping completion status.

This patch take care of Mike Christie's commets
Signed-off-by: NVikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

This addresses some header check warnings.  DRM headers which include
"drm.h" have been excluded, as they indirectly include types.h.
Signed-off-by: NBobby Powers <bobbypowers@gmail.com>
Cc: Chris Ball <cjb@laptop.org>
Cc: Dave Airlie <airlied@linux.ie>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

The <linux/device.h> header includes a lot of stuff, and
it in turn gets a lot of use just for the basic "struct device"
which appears so often.

Clean up the users as follows:

1) For those headers only needing "struct device" as a pointer
in fcn args, replace the include with exactly that.

2) For headers not really using anything from device.h, simply
delete the include altogether.

3) For headers relying on getting device.h implicitly before
being included themselves, now explicitly include device.h

4) For files in which doing #1 or #2 uncovers an implicit
dependency on some other header, fix by explicitly adding
the required header(s).

Any C files that were implicitly relying on device.h to be
present have already been dealt with in advance.

Total removals from #1 and #2: 51.  Total additions coming
from #3: 9.  Total other implicit dependencies from #4: 7.

As of 3.3-rc1, there were 110, so a net removal of 42 gives
about a 38% reduction in device.h presence in include/*
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

If a header file is making use of BUG, BUG_ON, BUILD_BUG_ON, or any
other BUG variant in a static inline (i.e. not in a #define) then
that header really should be including <linux/bug.h> and not just
expecting it to be implicitly present.

We can make this change risk-free, since if the files using these
headers didn't have exposure to linux/bug.h already, they would have
been causing compile failures/warnings.
Signed-off-by: NPaul Gortmaker <paul.gortmaker@windriver.com>

Signed-off-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NVikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

For offload iSCSI like qla4xxx CHAP entries are stored in FLASH.
This patch adds support to list CHAP entries stored in FLASH and
delete specified CHAP entry from FLASH using iscsi tools.
Signed-off-by: NNilesh Javali <nilesh.javali@qlogic.com>
Signed-off-by: NVikas Chaudhary <vikas.chaudhary@qlogic.com>
Reviewed-by: NMike Christie <michaelc@cs.wisc.edu>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

libata issues follow up srsts when the controller has a hard time
recording the signature-fis after a reset, or if the link supports port
multipliers.  libsas does not support port multipliers and no current
libsas lldds appear to need help retrieving the signature fis.  Revert
it for now to remove confusion.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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: NJack Wang <jack_wang@usish.com>
Acked-by: NJeff Garzik <jgarzik@redhat.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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

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: NJack Wang <jack_wang@usish.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

If we have a domain with sas and sata devices there may still be sas
recovery actions to take after peeling off the commands to send to
libata.
Reported-by: NAndrzej Jakowski <andrzej.jakowski@intel.com>
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

If the top level expander is hot removed, mark all child devices as gone
before unregistration to short circuit futile recovery.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>

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

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

The signature fis is re-transmitted when the link comes back so we
should be revalidating the ata device class, but that is left to a future
patch.
Signed-off-by: NDan Williams <dan.j.williams@intel.com>
Signed-off-by: NJames Bottomley <JBottomley@Parallels.com>