when GPSC/GPDB switch command fails, driver just returns without doing a
proper cleanup. This patch fixes this memory leak by calling sp->free() in
the error path.

Link: https://lore.kernel.org/r/20191105150657.8092-4-hmadhani@marvell.comReviewed-by: NEwan D. Milne <emilne@redhat.com>
Signed-off-by: NQuinn Tran <qutran@marvell.com>
Signed-off-by: NHimanshu Madhani <hmadhani@marvell.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

On switch, fabric and mgt command timeout, driver send Abort to tell FW to
return the original command.  If abort is timeout, then return both Abort
and original command for cleanup.

Fixes: 219d27d7 ("scsi: qla2xxx: Fix race conditions in the code for aborting SCSI commands")
Cc: stable@vger.kernel.org # 5.2
Link: https://lore.kernel.org/r/20191105150657.8092-3-hmadhani@marvell.comReviewed-by: NEwan D. Milne <emilne@redhat.com>
Signed-off-by: NQuinn Tran <qutran@marvell.com>
Signed-off-by: NHimanshu Madhani <hmadhani@marvell.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Current code will send PRLI with FC-NVMe bit set for the targets which
support only FCP. This may result into issue with targets which do not
understand NVMe and will go into a strange state. This patch would restart
the login process by going back to PLOGI state. The PLOGI state will force
the target to respond to correct PRLI request.

Fixes: c76ae845 ("scsi: qla2xxx: Add error handling for PLOGI ELS passthrough")
Cc: stable@vger.kernel.org # 5.4
Link: https://lore.kernel.org/r/20191105150657.8092-2-hmadhani@marvell.comReviewed-by: NEwan D. Milne <emilne@redhat.com>
Signed-off-by: NQuinn Tran <qutran@marvell.com>
Signed-off-by: NHimanshu Madhani <hmadhani@marvell.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch renames some variables in chap_server_compute_hash() to make it
harder to confuse the initiator's challenge with the target's challenge
when the mutual chap authentication is used.

Link: https://lore.kernel.org/r/20191017131037.9903-4-mlombard@redhat.comSigned-off-by: NMaurizio Lombardi <mlombard@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Link: https://lore.kernel.org/r/20191017131037.9903-3-mlombard@redhat.comSigned-off-by: NMaurizio Lombardi <mlombard@redhat.com>
Tested-by: NChris Leech <cleech@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch modifies the chap_server_compute_hash() function to make it
agnostic to the choice of hash algorithm that is used.  It also adds
support to three new hash algorithms: SHA1, SHA256 and SHA3-256.

The chap_got_response() function has been removed because the digest type
validity is already checked by chap_server_open()

Link: https://lore.kernel.org/r/20191028123822.5864-2-mlombard@redhat.comSigned-off-by: NMaurizio Lombardi <mlombard@redhat.com>
Tested-by: NChris Leech <cleech@redhat.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

According to SBC-2 a TRANSFER LENGTH field of zero means that 256 logical
blocks must be transferred. Make the SCSI tracing code follow SBC-2.

Fixes: bf816235 ("[SCSI] add scsi trace core functions and put trace points")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Link: https://lore.kernel.org/r/20191105215553.185018-1-bvanassche@acm.orgSigned-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Update lpfc version to 12.6.0.1

Link: https://lore.kernel.org/r/20191105005708.7399-12-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Some adapters support the ability to hold multiple adapter dumps on the
adapter flash. Some adapters default to enabling this feature while others
default to single-dump.

Make support uniform by enabling dual dump by default.

Link: https://lore.kernel.org/r/20191105005708.7399-11-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The current driver attempts to allocate an interrupt vector per cpu using
the systems managed IRQ allocator (flag PCI_IRQ_AFFINITY). The system IRQ
allocator will either provide the per-cpu vector, or return fewer
vectors. When fewer vectors, they are evenly spread between the numa nodes
on the system.  When run on an AMD architecture, if interrupts occur to a
cpu that is not in the same numa node as the adapter generating the
interrupt, there are extreme costs and overheads in performance.  Thus, if
1:1 vector allocation is used, or the "balanced" vectors in the other numa
nodes, performance can be hit significantly.

A much more performant model is to allocate interrupts only on the cpus
that are in the numa node where the adapter resides.  I/O completion is
still performed by the cpu where the I/O was generated. Unfortunately,
there is no flag to request the managed IRQ subsystem allocate vectors only
for the CPUs in the numa node as the adapter.

On AMD architecture, revert the irq allocation to the normal style
(non-managed) and then use irq_set_affinity_hint() to set the cpu
affinity and disable user-space rebalancing.

Tie the support into CPU offline/online. If the cpu being offlined owns a
vector, the vector is re-affinitized to one of the other CPUs on the same
numa node. If there are no more CPUs on the numa node, the vector has all
affinity removed and lets the system determine where it's serviced.
Similarly, when the cpu that owned a vector comes online, the vector is
reaffinitized to the cpu.

Link: https://lore.kernel.org/r/20191105005708.7399-10-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The recent affinitization didn't address cpu offlining/onlining.  If an
interrupt vector is shared and the low order cpu owning the vector is
offlined, as interrupts are managed, the vector is taken offline. This
causes the other CPUs sharing the vector will hang as they can't get io
completions.

Correct by registering callbacks with the system for Offline/Online
events. When a cpu is taken offline, its eq, which is tied to an interrupt
vector is found. If the cpu is the "owner" of the vector and if the
eq/vector is shared by other CPUs, the eq is placed into a polled mode.
Additionally, code paths that perform io submission on the "sharing CPUs"
will check the eq state and poll for completion after submission of new io
to a wq that uses the eq.

Similarly, when a cpu comes back online and owns an offlined vector, the eq
is taken out of polled mode and rearmed to start driving interrupts for eq.

Link: https://lore.kernel.org/r/20191105005708.7399-9-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Current message on FAWWN events is rather cryptic.

Expand the message to clarify its meaning.

Link: https://lore.kernel.org/r/20191105005708.7399-8-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Prior to the last FC-NVME-2 draft, SLER and CONF were independent.  SLER
now requires CONF to be set.

Revise the NVME PRLI checking to look for both inorder to enable SLER.

Link: https://lore.kernel.org/r/20191105005708.7399-7-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The recently posted patch had a typo that incorrectly tested the receiving
function.

Fix the typo (change == to !=)

Fixes: 95bfc6d8 ("scsi: lpfc: Make FW logging dynamically configurable")
Link: https://lore.kernel.org/r/20191105005708.7399-6-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

During heavy RCN activity and log_verbose = 0 we see these messages:

  2754 PRLI failure DID:521245 Status:x9/xb2c00, data: x0
  0231 RSCN timeout Data: x0 x3
  0230 Unexpected timeout, hba link state x5

This is due to delayed RSCN activity.

Correct by avoiding the timeout thus the messages by restarting the
discovery timeout whenever an rscn is received.

Filter PRLI responses such that severity depends on whether expected for
the configuration or not. For example, PRLI errors on a fabric will be
informational (they are expected), but Point-to-Point errors are not
necessarily expected so they are raised to an error level.

Link: https://lore.kernel.org/r/20191105005708.7399-5-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

When reading sysfs nvme_info file while a remote port leaves and comes
back, a NULL pointer is encountered. The issue is due to ndlp list
corruption as the the nvme_info_show does not use the same lock as the rest
of the code.

Correct by removing the rcu_xxx_lock calls and replace by the host_lock and
phba->hbaLock spinlocks that are used by the rest of the driver.  Given
we're called from sysfs, we are safe to use _irq rather than _irqsave.

Link: https://lore.kernel.org/r/20191105005708.7399-4-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The driver today is reading service parameters from the firmware and then
overwriting the firmware-provided values with values of its own.  There are
some switch features that require preliminary FLOGI's that are
switch-specific and done prior to the actual fabric FLOGI for traffic.  The
fw will perform those FLOGIs and will revise the service parameters for the
features configured. As the driver later overwrites those values with its
own values, it misconfigures things like BBSCN use by doing so.

Correct by eliminating the driver-overwrite of firmware values. The driver
correctly re-reads the service parameters after each link up to obtain the
latest values from firmware.

Link: https://lore.kernel.org/r/20191105005708.7399-3-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

If the driver receives a login that is later then LOGO'd by the remote port
(aka ndlp), the driver, upon the completion of the LOGO ACC transmission,
will logout the node and unregister the rpi that is being used for the
node.  As part of the unreg, the node's rpi value is replaced by the
LPFC_RPI_ALLOC_ERROR value.  If the port is subsequently offlined, the
offline walks the nodes and ensures they are logged out, which possibly
entails unreg'ing their rpi values.  This path does not validate the node's
rpi value, thus doesn't detect that it has been unreg'd already.  The
replaced rpi value is then used when accessing the rpi bitmask array which
tracks active rpi values.  As the LPFC_RPI_ALLOC_ERROR value is not a valid
index for the bitmask, it may fault the system.

Revise the rpi release code to detect when the rpi value is the replaced
RPI_ALLOC_ERROR value and ignore further release steps.

Link: https://lore.kernel.org/r/20191105005708.7399-2-jsmart2021@gmail.comSigned-off-by: NDick Kennedy <dick.kennedy@broadcom.com>
Signed-off-by: NJames Smart <jsmart2021@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

simply not needed there - neither sg_new_read() nor sg_new_write() need
it.

Link: https://lore.kernel.org/r/20191017193925.25539-8-viro@ZenIV.linux.org.ukSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Just use plain copy_from_user() and get_user().  Note that while a
buf-derived pointer gets stored into ->dxferp, all places that actually use
the resulting value feed it either to import_iovec() or to
import_single_range(), and both will do validation.

Link: https://lore.kernel.org/r/20191017193925.25539-7-viro@ZenIV.linux.org.ukSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Use copy_..._user() instead, both in sg_read() and in sg_read_oxfer().  And
don't open-code memdup_user()...

Link: https://lore.kernel.org/r/20191017193925.25539-6-viro@ZenIV.linux.org.ukSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

... just use copy_from_user().  We copy only SZ_SG_IO_HDR bytes, so that
would, strictly speaking, loosen the check.  However, for call chains via
->write() the caller has actually checked the entire range and SG_IO passes
exactly SZ_SG_IO_HDR for count.  So no visible behaviour changes happen if
we check only what we really need for copyin.

Link: https://lore.kernel.org/r/20191017193925.25539-5-viro@ZenIV.linux.org.ukSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

We don't need to allocate a temporary buffer and read the entire structure
in it, only to fetch a single field and free what we'd allocated.  Just use
get_user() and be done with it...

Link: https://lore.kernel.org/r/20191017193925.25539-4-viro@ZenIV.linux.org.ukSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Link: https://lore.kernel.org/r/20191017193925.25539-3-viro@ZenIV.linux.org.ukSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Link: https://lore.kernel.org/r/20191017193925.25539-2-viro@ZenIV.linux.org.ukSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

First of all, __put_user() can fail with access_ok() succeeding.  And
access_ok() + __copy_to_user() is spelled copy_to_user()...

__put_user() *can* fail with access_ok() succeeding...

Link: https://lore.kernel.org/r/20191017193925.25539-1-viro@ZenIV.linux.org.ukSigned-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Acked-by: NDouglas Gilbert <dgilbert@interlog.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

The memory chunk io_req is released by mempool_free. Accessing
io_req->start_time will result in a use after free bug. The variable
start_time is a backup of the timestamp. So, use start_time here to
avoid use after free.

Link: https://lore.kernel.org/r/1572881182-37664-1-git-send-email-bianpan2016@163.comSigned-off-by: NPan Bian <bianpan2016@163.com>
Reviewed-by: NSatish Kharat <satishkh@cisco.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

This patch fixes an unintended sign extension on left shifts. From Colin
King: "Shifting a u8 left will cause the value to be promoted to an
integer. If the top bit of the u8 is set then the following conversion to
an u64 will sign extend the value causing the upper 32 bits to be set in
the result."

Fix this by using get_unaligned_be*() instead.

Fixes: bf816235 ("[SCSI] add scsi trace core functions and put trace points")
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Link: https://lore.kernel.org/r/20191101211447.187151-1-bvanassche@acm.orgReported-by: NColin Ian King <colin.king@canonical.com>
Signed-off-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Only csio_hw_free() calling csio_dfs_destroy() and it is not checking
return value. So remove the return from csio_dfs_destroy().

Link: https://lore.kernel.org/r/20191028194234.GA27848@sauravSigned-off-by: NSaurav Girepunje <saurav.girepunje@gmail.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

debugfs_remove_recursive() has taken the null pointer into account.  Remove
the null check before debugfs_remove_recursive().

Link: https://lore.kernel.org/r/20191026195625.GA22455@sauravSigned-off-by: NSaurav Girepunje <saurav.girepunje@gmail.com>
Reviewed-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Replace assignment of 0 to pointer with NULL assignment.

Link: https://lore.kernel.org/r/20191025135010.GA6191@sauravSigned-off-by: NSaurav Girepunje <saurav.girepunje@gmail.com>
Acked-by: NJack Wang <jinpu.wang@cloud.ionos.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

It isn't necessary to check the host depth in scsi_queue_rq() any more
since it has been respected by blk-mq before calling scsi_queue_rq() via
getting driver tag.

Lots of LUNs may attach to same host and per-host IOPS may reach millions,
so we should avoid expensive atomic operations on the host-wide counter in
the IO path.

This patch implements scsi_host_busy() via blk_mq_tagset_busy_iter() with
one scsi command state for reading the count of busy IOs for scsi_mq.

It is observed that IOPS is increased by 15% in IO test on scsi_debug (32
LUNs, 32 submit queues, 1024 can_queue, libaio/dio) in a dual-socket
system.

Cc: Jens Axboe <axboe@kernel.dk>
Cc: Ewan D. Milne <emilne@redhat.com>
Cc: Omar Sandoval <osandov@fb.com>,
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>,
Cc: James Bottomley <james.bottomley@hansenpartnership.com>,
Cc: Christoph Hellwig <hch@lst.de>,
Cc: Kashyap Desai <kashyap.desai@broadcom.com>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Laurence Oberman <loberman@redhat.com>
Cc: Bart Van Assche <bvanassche@acm.org>
Link: https://lore.kernel.org/r/20191025065855.6309-1-ming.lei@redhat.comSigned-off-by: NMing Lei <ming.lei@redhat.com>
Reviewed-by: NJens Axboe <axboe@kernel.dk>
Reviewed-by: NBart Van Assche <bvanassche@acm.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Declare all variables that hold dev_cmd_type values as an enum instead of
as an int.

Cc: Yaniv Gardi <ygardi@codeaurora.org>
Cc: Subhash Jadavani <subhashj@codeaurora.org>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20191029230710.211926-3-bvanassche@acm.orgSigned-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NAvri Altman <avri.altman@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Fix the following three kernel-doc warnings:

drivers/scsi/ufs/ufs_bsg.c:165: warning: Function parameter or member 'hba' not described in 'ufs_bsg_remove'
drivers/scsi/ufs/ufshcd.c:5789: warning: Function parameter or member 'cmd_type' not described in 'ufshcd_issue_devman_upiu_cmd'
drivers/scsi/ufs/ufshcd.c:5789: warning: Excess function parameter 'msgcode' description in 'ufshcd_issue_devman_upiu_cmd'

Cc: Yaniv Gardi <ygardi@codeaurora.org>
Cc: Subhash Jadavani <subhashj@codeaurora.org>
Cc: Stanley Chu <stanley.chu@mediatek.com>
Cc: Avri Altman <avri.altman@wdc.com>
Cc: Tomas Winkler <tomas.winkler@intel.com>
Link: https://lore.kernel.org/r/20191029230710.211926-2-bvanassche@acm.orgSigned-off-by: NBart Van Assche <bvanassche@acm.org>
Reviewed-by: NAvri Altman <avri.altman@wdc.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

There is no need to call ufshcd_def_desc_sizes() in ufshcd_init(), since
descriptor lengths will be checked and initialized later in
ufshcd_init_desc_sizes().

Fixes: a4b0e8a4(scsi: ufs: Factor out ufshcd_read_desc_param)
Link: https://lore.kernel.org/r/BN7PR08MB5684A3ACE214C3D4792CE729DB610@BN7PR08MB5684.namprd08.prod.outlook.comSigned-off-by: NBean Huo <beanhuo@micron.com>
Acked-by: Avri Altman <avri.altman.wdc.com>
Reviewed-by: NCan Guo <cang@codeaurora.org>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

While v2.6.26 commit b75db731 ("[SCSI] zfcp: Add qtcb dump to hba debug
trace") is right that we don't want to flood the (payload) trace ring
buffer, we don't trace successful FCP command responses by default.  So we
can include the channel log for problem determination with failed responses
of any FSF request type.

Fixes: b75db731 ("[SCSI] zfcp: Add qtcb dump to hba debug trace")
Fixes: a54ca0f6 ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.")
Cc: <stable@vger.kernel.org> #2.6.38+
Link: https://lore.kernel.org/r/e37597b5c4ae123aaa85fd86c23a9f71e994e4a9.1572018132.git.bblock@linux.ibm.comReviewed-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NSteffen Maier <maier@linux.ibm.com>
Signed-off-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

No functional change.

The unary not operator only applies to the sub expression before the
logical or. So we return early if (not running) or failed.

Link: https://lore.kernel.org/r/df4f897f6e83eaa528465d0858d5a22daac47a2f.1572018132.git.bblock@linux.ibm.comReviewed-by: NJens Remus <jremus@linux.ibm.com>
Reviewed-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NSteffen Maier <maier@linux.ibm.com>
Signed-off-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Replace the static define (ZFCP_DIAG_MAX_AGE) with a per-adapter variable
(${adapter}->diagnostics->max_age). This new variable is exported via
sysfs, along with other, already existing adapter variables, and can both
be read and written. This way users can choose how much time should pass
between refreshes of diagnostic buffers. The default value for the age
remains to be five seconds.

By setting this new variable to 0, the caching of diagnostic buffers for
userspace accesses can also be completely removed.

All diagnostic buffers of a given adapter are subject to this setting in
the same way.

Link: https://lore.kernel.org/r/b1d0977cc884b16dd4ca6418e4320c56a4c31d63.1572018132.git.bblock@linux.ibm.comReviewed-by: NSteffen Maier <maier@linux.ibm.com>
Signed-off-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

Adds implicit updates of cached diagnostics via Exchange Config Data when
reading sysfs attributes interfacing them. Right now this only affects the
new B2B-Credit diagnostic attribute.

This uses the same mechanism previously also used for cached diagnostics
of Exchange Port Data.

Link: https://lore.kernel.org/r/60a94f55f2630b74b468fed5f39880208abb2679.1572018132.git.bblock@linux.ibm.comReviewed-by: NSteffen Maier <maier@linux.ibm.com>
Signed-off-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>

In addition to the diagnostic data from the local SFP transceiver this
patch adds an interface to read the advertised buffer-to-buffer credit from
the local FC_Port.

With this patch the userspace-interface will only read data stored in the
corresponding "diagnostic buffer" (that was stored during completion of a
previous Exchange Config Data command). Implicit updating will follow later
in this series.

Link: https://lore.kernel.org/r/8a53aef87b53c50cfb1a3425b799bacb6f82b832.1572018132.git.bblock@linux.ibm.comReviewed-by: NSteffen Maier <maier@linux.ibm.com>
Signed-off-by: NBenjamin Block <bblock@linux.ibm.com>
Signed-off-by: NMartin K. Petersen <martin.petersen@oracle.com>