This is a batch of changes that didn't make it in the initial pull
request because the lpfc series had to be rebased to redo an incorrect
split. It's basically driver updates to lpfc, target, bnx2fc and ufs
with the rest being minor updates except the sr_block_release one
which fixes a use after free introduced by the removal of the global
mutex in the first patch set.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull more SCSI updates from James Bottomley:
"This is a batch of changes that didn't make it in the initial pull
request because the lpfc series had to be rebased to redo an incorrect
split.
It's basically driver updates to lpfc, target, bnx2fc and ufs with the
rest being minor updates except the sr_block_release one which fixes a
use after free introduced by the removal of the global mutex in the
first patch set"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (35 commits)
scsi: core: Add DID_ALLOC_FAILURE and DID_MEDIUM_ERROR to hostbyte_table
scsi: ufs: Use ufshcd_config_pwr_mode() when scaling gear
scsi: bnx2fc: fix boolreturn.cocci warnings
scsi: zfcp: use fallthrough;
scsi: aacraid: do not overwrite retval in aac_reset_adapter()
scsi: sr: Fix sr_block_release()
scsi: aic7xxx: Remove more FreeBSD-specific code
scsi: mpt3sas: Fix kernel panic observed on soft HBA unplug
scsi: ufs: set device as active power mode after resetting device
scsi: iscsi: Report unbind session event when the target has been removed
scsi: lpfc: Change default SCSI LUN QD to 64
scsi: libfc: rport state move to PLOGI if all PRLI retry exhausted
scsi: libfc: If PRLI rejected, move rport to PLOGI state
scsi: bnx2fc: Update the driver version to 2.12.13
scsi: bnx2fc: Fix SCSI command completion after cleanup is posted
scsi: bnx2fc: Process the RQE with CQE in interrupt context
scsi: target: use the stack for XCOPY passthrough cmds
scsi: target: increase XCOPY I/O size
scsi: target: avoid per-loop XCOPY buffer allocations
scsi: target: drop xcopy DISK BLOCK LENGTH debug
...
Upper-layer drivers allocate their SBALs by calling qdio_alloc_buffers()
for each individual queue. But when later passing the SBAL addresses to
qdio_establish(), they need to be in a single array of pointers.
So if the driver uses multiple Input or Output queues, it needs to
allocate a temporary array just to present all its SBAL pointers in this
layout.
This patch slightly changes the format of the QDIO initialization data,
so that drivers can pass a per-queue array where each element points to
a queue's SBAL array.
zfcp doesn't use multiple queues, so the impact there is trivial.
For qeth this brings a nice reduction in complexity, and removes
a page-sized allocation.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
In preparation for a subsequent patch, move the setup of init_data into
the only caller.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
All that qdio_allocate() actually uses from the init_data is the cdev,
and the number of Input and Output Queues. Have the driver pass those as
parameters, and defer the init_data processing into qdio_establish().
This includes writing per-device(!) trace entries, and most of the
sanity checks.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
update changing all our txt files to rst ones. Excluding that, we
have the usual driver updates (qla2xxx, ufs, lpfc, zfcp, ibmvfc,
pm80xx, aacraid), a treewide update for scnprintf and some other minor
updates. The major core update is Hannes moving functions out of the
aacraid driver and into the core.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI updates from James Bottomley:
"This series has a huge amount of churn because it pulls in Mauro's doc
update changing all our txt files to rst ones.
Excluding that, we have the usual driver updates (qla2xxx, ufs, lpfc,
zfcp, ibmvfc, pm80xx, aacraid), a treewide update for scnprintf and
some other minor updates.
The major core change is Hannes moving functions out of the aacraid
driver and into the core"
* tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (223 commits)
scsi: aic7xxx: aic97xx: Remove FreeBSD-specific code
scsi: ufs: Do not rely on prefetched data
scsi: dc395x: remove dc395x_bios_param
scsi: libiscsi: Fix error count for active session
scsi: hpsa: correct race condition in offload enabled
scsi: message: fusion: Replace zero-length array with flexible-array member
scsi: qedi: Add PCI shutdown handler support
scsi: qedi: Add MFW error recovery process
scsi: ufs: Enable block layer runtime PM for well-known logical units
scsi: ufs-qcom: Override devfreq parameters
scsi: ufshcd: Let vendor override devfreq parameters
scsi: ufshcd: Update the set frequency to devfreq
scsi: ufs: Resume ufs host before accessing ufs device
scsi: ufs-mediatek: customize the delay for enabling host
scsi: ufs: make HCE polling more compact to improve initialization latency
scsi: ufs: allow custom delay prior to host enabling
scsi: ufs-mediatek: use common delay function
scsi: ufs: introduce common and flexible delay function
scsi: ufs: use an enum for host capabilities
scsi: ufs: fix uninitialized tx_lanes in ufshcd_disable_tx_lcc()
...
Log any FC Endpoint Security errors to the kernel ring buffer with rate-
limiting.
Link: https://lore.kernel.org/r/20200312174505.51294-11-maier@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Enable for explicit FCP channel FC Endpoint Security error reporting and
handle any FSF security errors according to specification. Take the
following recovery actions when a FSF_SECURITY_ERROR is reported for the
specified FSF commands:
- Open Port: Retry the command if possible
- Send FCP : Physically close the remote port and reopen
For Open Port the command status is set to error, which triggers a retry.
For Send FCP the command status is set to error and recovery is triggered
to physically reopen the remote port.
Link: https://lore.kernel.org/r/20200312174505.51294-10-maier@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Trace changes in Fibre Channel Endpoint Security capabilities of FCP
devices as well as changes in Fibre Channel Endpoint Security state of
their connections to FC remote ports as FC Endpoint Security changes with
trace level 3 in HBA DBF.
A change in FC Endpoint Security capabilities of FCP devices is traced as
response to FSF command FSF_QTCB_EXCHANGE_PORT_DATA with a trace tag of
"fsfcesa" and a WWPN of ZFCP_DBF_INVALID_WWPN = 0x0000000000000000 (see
FC-FS-4 §18 "Name_Identifier Formats", NAA field).
A change in FC Endpoint Security state of connections between FCP devices
and FC remote ports is traced as response to FSF command
FSF_QTCB_OPEN_PORT_WITH_DID with a trace tag of "fsfcesp".
Example trace record of FC Endpoint Security capability change of FCP
device formatted with zfcpdbf from s390-tools:
Timestamp : ...
Area : HBA
Subarea : 00
Level : 3
Exception : -
CPU ID : ...
Caller : 0x...
Record ID : 5 ZFCP_DBF_HBA_FCES
Tag : fsfcesa FSF FC Endpoint Security adapter
Request ID : 0x...
Request status : 0x00000010
FSF cmnd : 0x0000000e FSF_QTCB_EXCHANGE_PORT_DATA
FSF sequence no: 0x...
FSF issued : ...
FSF stat : 0x00000000 FSF_GOOD
FSF stat qual : n/a
Prot stat : n/a
Prot stat qual : n/a
Port handle : 0x00000000 none (invalid)
LUN handle : n/a
WWPN : 0x0000000000000000 ZFCP_DBF_INVALID_WWPN
FCES old : 0x00000000 old FC Endpoint Security
FCES new : 0x00000007 new FC Endpoint Security
Example trace record of FC Endpoint Security change of connection to
FC remote port formatted with zfcpdbf from s390-tools:
Timestamp : ...
Area : HBA
Subarea : 00
Level : 3
Exception : -
CPU ID : ...
Caller : 0x...
Record ID : 5 ZFCP_DBF_HBA_FCES
Tag : fsfcesp FSF FC Endpoint Security port
Request ID : 0x...
Request status : 0x00000010
FSF cmnd : 0x00000005 FSF_QTCB_OPEN_PORT_WITH_DID
FSF sequence no: 0x...
FSF issued : ...
FSF stat : 0x00000000 FSF_GOOD
FSF stat qual : n/a
Prot stat : n/a
Prot stat qual : n/a
Port handle : 0x...
WWPN : 0x500507630401120c WWPN
FCES old : 0x00000000 old FC Endpoint Security
FCES new : 0x00000004 new FC Endpoint Security
Link: https://lore.kernel.org/r/20200312174505.51294-9-maier@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Log the usage of and subsequent changes in FC Endpoint Security of
connections between FCP devices and FC remote ports to the kernel ring
buffer. Activation of FC Endpoint Security is logged as informational.
Change and deactivation are logged as warning.
No logging takes place, if FC Endpoint Security is not used (i.e. never
activated) on a connection or if it does not change during reopen of a port
(e.g. due to adapter or port recovery).
Link: https://lore.kernel.org/r/20200312174505.51294-8-maier@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Fedor Loshakov <loshakov@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Add an interface to read Fibre Channel Endpoint Security information of FCP
channels and their connections to FC remote ports. It comes in the form of
new sysfs attributes that are attached to the CCW device representing the
FCP device and its zfcp port objects.
The read-only sysfs attribute "fc_security" of a CCW device representing a
FCP device shows the FC Endpoint Security capabilities of the device.
Possible values are: "unknown", "unsupported", "none", or a comma-
separated list of one or more mnemonics and/or one hexadecimal value
representing the supported FC Endpoint Security:
Authentication: Authentication supported
Encryption : Encryption supported
The read-only sysfs attribute "fc_security" of a zfcp port object shows the
FC Endpoint Security used on the connection between its parent FCP device
and the FC remote port. Possible values are: "unknown", "unsupported",
"none", or a mnemonic or hexadecimal value representing the FC Endpoint
Security used:
Authentication: Connection has been authenticated
Encryption : Connection is encrypted
Both sysfs attributes may return hexadecimal values instead of mnemonics,
if the mnemonic lookup table does not contain an entry for the FC Endpoint
Security reported by the FCP device.
Link: https://lore.kernel.org/r/20200312174505.51294-7-maier@linux.ibm.com
Reviewed-by: Fedor Loshakov <loshakov@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Introduce automatic variables for adapter and QTCB bottom in
zfcp_fsf_open_port_handler(). This facilitates subsequent changes to meet
the 80 character per line limit.
Link: https://lore.kernel.org/r/20200312174505.51294-6-maier@linux.ibm.com
Reviewed-by: Fedor Loshakov <loshakov@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When we get an unsolicited notification on local link went down,
zfcp_fsf_status_read_link_down() calls zfcp_fsf_link_down_info_eval().
This only blocks rports, and sets ZFCP_STATUS_ADAPTER_LINK_UNPLUGGED and
ZFCP_STATUS_COMMON_ERP_FAILED. Only the fc_host port_state changes to
"Linkdown", because zfcp_scsi_get_host_port_state() is an active callback
and uses the adapter status.
Other fc_host attributes model, port_id, port_type, speed, fabric_name (and
zfcp device attributes card_version, peer_wwpn, peer_wwnn, peer_d_id) which
depend on a local link, continued to show their last known "good" value.
Only if something triggered an exchange config data, some values were
updated to their unknown equivalent via case
FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE due to local link down. Triggers for
exchange config data are adapter recovery, or reading any of the following
zfcp-specific scsi host sysfs attributes "requests", "megabytes", or
"seconds_active" in /sys/devices/css*/*.*.*/*.*.*/host*/scsi_host/host*/.
The other fc_host attributes active_fc4s and permanent_port_name continued
to show their last known "good" value. Only if something triggered an
exchange port data, some values changed. Active_fc4s became all zeros as
unknown equivalent during link down. Permanent_port_name does not depend
on a local link. But for non-NPIV FCP devices, permanent_port_name
erroneously became whatever value fc_host port_name had at that point in
time (see previous paragraph). Triggers for exchange port data are the
zfcp-specific scsi host sysfs attribute "utilization", or
[{reset,get}_fc_host_stats] write anything into "reset_statistics" or read
any of the other attributes under
/sys/devices/css*/*.*.*/*.*.*/host*/fc_host/host*/statistics/.
(cf. v4.9 commit bd77befa5b ("zfcp: fix fc_host port_type with NPIV"))
This is particularly confusing when using "lszfcp -b <fcpdevbusid> -Ha" or
dbginfo.sh which read fc_host attributes and also scsi_host attributes.
After link down, the first invocation produces (abbreviated):
Class = "fc_host"
active_fc4s = "0x00 0x00 0x01 0x00 ..."
...
fabric_name = "0x10000027f8e04c49"
...
permanent_port_name = "0xc05076e4588059c1"
port_id = "0x244800"
port_state = "Linkdown"
port_type = "NPort (fabric via point-to-point)"
...
speed = "16 Gbit"
Class = "scsi_host"
...
megabytes = "0 0"
...
requests = "0 0 0"
seconds_active = "37"
...
utilization = "0 0 0"
The second and next invocations produce (abbreviated):
Class = "fc_host"
active_fc4s = "0x00 0x00 0x00 0x00 ..."
...
fabric_name = "0x0"
...
permanent_port_name = "0x0"
port_id = "0x000000"
port_state = "Linkdown"
port_type = "Unknown"
...
speed = "unknown"
Class = "scsi_host"
...
megabytes = "0 0"
...
requests = "0 0 0"
seconds_active = "38"
...
utilization = "0 0 0"
Factor out the resetting of local link dependent fc_host attributes from
zfcp_fsf_exchange_config_data_handler() case
FSF_EXCHANGE_CONFIG_DATA_INCOMPLETE into a new helper function
zfcp_fsf_fc_host_link_down(). All code places that detect local link down
(SRB, FSF_PROT_LINK_DOWN, xconf data/port incomplete) call
zfcp_fsf_link_down_info_eval(). Call the new helper from there. This works
because zfcp_fsf_link_down_info_eval() and thus the helper is called before
zfcp_fsf_exchange_{config,port}_evaluate().
Port_name and node_name are always valid, so never reset them.
Get the permanent_port_name from exchange port data unconditionally as it
always has a valid known good value, even during link down.
Note: Rather than hardcode in zfcp_fsf_exchange_config_evaluate(), fc_host
supported_classes could theoretically get its value from
fsf_qtcb_bottom_port.class_of_service in zfcp_fsf_exchange_port_evaluate().
When the link comes back, we get a different notification, perform adapter
recovery, and this triggers an implicit exchange config data followed by
exchange port data filling in the link dependent fc_host attributes with
known good values again.
Link: https://lore.kernel.org/r/20200312174505.51294-5-maier@linux.ibm.com
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Manufacturer, HBA model, firmware version, and hardware version. Use the
same value format as for the driver-specific attributes. Keep the
driver-specific attributes for stable user space sysfs API.
Link: https://lore.kernel.org/r/20200312174505.51294-4-maier@linux.ibm.com
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
FICON Express8S or older, as well as card features newer than FICON
Express16S+ have no certain firmware level requirement.
FICON Express16S or FICON Express16S+ have the following
minimum firmware level requirements to show a proper fabric name value:
z13 machine
FICON Express16S , MCL P08424.005 , LIC version 0x00000721
z14 machine
FICON Express16S , MCL P42611.008 , LIC version 0x10200069
FICON Express16S+ , MCL P42625.010 , LIC version 0x10300147
Otherwise, the read value is not the fabric name.
Each FCP channel of these card features might need one SAN fabric re-login
after concurrent microcode update in order to show the proper fabric name.
Possible ways to trigger a SAN fabric re-login are one of: Pull fibres
between FCP channel port and SAN switch port on either side and re-plug,
disable SAN switch port adjacent to FCP channel port and re-enable switch
port, or at Service Element toggle off all CHPIDs of FCP channel over all
LPARs and toggle CHPIDs on again. Zfcp operating subchannels (FCP devices)
on such FCP channel recovers a fabric re-login.
Initialize fabric name for any topology and have it an invalid WWPN 0x0 for
anything but fabric topology. Otherwise for e.g. point-to-point topology
one could see the initial -1 from fc_host_setup() and after a link unplug
our fabric name would turn to 0x0 (with subsequent commit ("zfcp: fix
fc_host attributes that should be unknown on local link down") and stay 0x0
on link replug. I did not initialize to 0x0 somewhere even earlier in the
code path such that it would not flap from real to 0x0 to real on e.g. an
exchange config data with fabric topology.
Link: https://lore.kernel.org/r/20200312174505.51294-3-maier@linux.ibm.com
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
v2.6.27 commit cc8c282963 ("[SCSI] zfcp: Automatically attach remote
ports") introduced zfcp automatic port scan.
Before that, the user had to use the sysfs attribute "port_add" of an FCP
device (adapter) to add and open remote (target) ports, even for the remote
peer port in point-to-point topology. That code path did a proper port open
recovery trigger taking the erp_lock.
Since above commit, a new helper function zfcp_erp_open_ptp_port()
performed an UNlocked port open recovery trigger. This can race with other
parallel recovery triggers. In zfcp_erp_action_enqueue() this could corrupt
e.g. adapter->erp_total_count or adapter->erp_ready_head.
As already found for fabric topology in v4.17 commit fa89adba19 ("scsi:
zfcp: fix infinite iteration on ERP ready list"), there was an endless loop
during tracing of rport (un)block. A subsequent v4.18 commit 9e156c54ac
("scsi: zfcp: assert that the ERP lock is held when tracing a recovery
trigger") introduced a lockdep assertion for that case.
As a side effect, that lockdep assertion now uncovered the unlocked code
path for PtP. It is from within an adapter ERP action:
zfcp_erp_strategy[1479] intentionally DROPs erp lock around
zfcp_erp_strategy_do_action()
zfcp_erp_strategy_do_action[1441] NO erp lock
zfcp_erp_adapter_strategy[876] NO erp lock
zfcp_erp_adapter_strategy_open[855] NO erp lock
zfcp_erp_adapter_strategy_open_fsf[806]NO erp lock
zfcp_erp_adapter_strat_fsf_xconf[772] erp lock only around
zfcp_erp_action_to_running(),
BUT *_not_* around
zfcp_erp_enqueue_ptp_port()
zfcp_erp_enqueue_ptp_port[728] BUG: *_not_* taking erp lock
_zfcp_erp_port_reopen[432] assumes to be called with erp lock
zfcp_erp_action_enqueue[314] assumes to be called with erp lock
zfcp_dbf_rec_trig[288] _checks_ to be called with erp lock:
lockdep_assert_held(&adapter->erp_lock);
It causes the following lockdep warning:
WARNING: CPU: 2 PID: 775 at drivers/s390/scsi/zfcp_dbf.c:288
zfcp_dbf_rec_trig+0x16a/0x188
no locks held by zfcperp0.0.17c0/775.
Fix this by using the proper locked recovery trigger helper function.
Link: https://lore.kernel.org/r/20200312174505.51294-2-maier@linux.ibm.com
Fixes: cc8c282963 ("[SCSI] zfcp: Automatically attach remote ports")
Cc: <stable@vger.kernel.org> #v2.6.27+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Four small fixes. Three are in drivers for fairly obvious bugs. The
fourth is a set of regressions introduced by the compat_ioctl changes
because some of the compat updates wrongly replaced .ioctl instead of
.compat_ioctl.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"Four small fixes.
Three are in drivers for fairly obvious bugs. The fourth is a set of
regressions introduced by the compat_ioctl changes because some of the
compat updates wrongly replaced .ioctl instead of .compat_ioctl"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
scsi: compat_ioctl: cdrom: Replace .ioctl with .compat_ioctl in four appropriate places
scsi: zfcp: fix wrong data and display format of SFP+ temperature
scsi: sd_sbc: Fix sd_zbc_report_zones()
scsi: libfc: free response frame from GPN_ID
When implementing support for retrieval of local diagnostic data from the
FCP channel, the wrong data format was assumed for the temperature of the
local SFP+ connector. The Fibre Channel Link Services (FC-LS-3)
specification is not clear on the format of the stored integer, and only
after consulting the SNIA specification SFF-8472 did we realize it is
stored as two's complement. Thus, the used data and display format is
wrong, and highly misleading for users when the temperature should drop
below 0°C (however unlikely that may be).
To fix this, change the data format in `struct fsf_qtcb_bottom_port` from
unsigned to signed, and change the printf format string used to generate
`zfcp_sysfs_adapter_diag_sfp_temperature_show()` from `%hu` to `%hd`.
Link: https://lore.kernel.org/r/d6e3be5428da5c9490cfff4df7cae868bc9f1a7e.1582039501.git.bblock@linux.ibm.com
Fixes: a10a61e807 ("scsi: zfcp: support retrieval of SFP Data via Exchange Port Data")
Fixes: 6028f7c4cd ("scsi: zfcp: introduce sysfs interface for diagnostics of local SFP transceiver")
Cc: <stable@vger.kernel.org> # 5.5+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Fedor Loshakov <loshakov@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
sbale->addr holds an absolute address (or for some FCP usage, an opaque
request ID), and should only be used with proper virt/phys translation.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
While v2.6.26 commit b75db73159 ("[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: b75db73159 ("[SCSI] zfcp: Add qtcb dump to hba debug trace")
Fixes: a54ca0f62f ("[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.com
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin 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.com
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin 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.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin 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.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin 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.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This patch adds implicit updates to the sysfs entries that read the
diagnostic data stored in the "caching buffer" for Exchange Port Data.
An update is triggered once the buffer is older than ZFCP_DIAG_MAX_AGE
milliseconds (5s). This entails sending an Exchange Port Data command to
the FCP-Channel, and during its ingress path updating the cached data and
the timestamp. To prevent multiple concurrent userspace-applications from
triggering this update in parallel we synchronize all of them using a
wait-queue (waiting threads are interruptible; the updating thread is not).
Link: https://lore.kernel.org/r/c145b5cfc99a63b6a018b1184fbd27bb09c955f5.1572018132.git.bblock@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This adds an interface to read the diagnostics of the local SFP transceiver
of an FCP-Channel from userspace. This comes in the form of new sysfs
entries that are attached to the CCW device representing the FCP
device. Each type of data gets its own sysfs entry; the whole collection of
entries is pooled into a new child-directory of the CCW device node:
"diagnostics".
Adds sysfs entries for:
* sfp_invalid: boolean value evaluating to whether the following 5
fields are invalid; {0, 1}; 1 - invalid
* temperature: transceiver temp.; unit 1/256°C;
range [-128°C, +128°C]
* vcc: supply voltage; unit 100μV; range [0, 6.55V]
* tx_bias: transmitter laser bias current; unit 2μA;
range [0, 131mA]
* tx_power: coupled TX output power; unit 0.1μW; range [0, 6.5mW]
* rx_power: received optical power; unit 0.1μW; range [0, 6.5mW]
* optical_port: boolean value evaluating to whether the FCP-Channel has
an optical port; {0, 1}; 1 - optical
* fec_active: boolean value evaluating to whether 16G FEC is active;
{0, 1}; 1 - active
* port_tx_type: nibble describing the port type; {0, 1, 2, 3};
0 - unknown, 1 - short wave,
2 - long wave LC 1310nm, 3 - long wave LL 1550nm
* connector_type: two bits describing the connector type; {0, 1};
0 - unknown, 1 - SFP+
This is only supported if the FCP-Channel in turn supports reporting the
SFP Diagnostic Data, otherwise read() on these new entries will return
EOPNOTSUPP (this affects only adapters older than FICON Express8S, on
Mainframe generations older than z14). Other possible errors for read()
include ENOLINK, ENODEV and ENOMEM.
With this patch the userspace-interface will only read data stored in
the corresponding "diagnostic buffer" (that was stored during completion
of an previous Exchange Port Data command). Implicit updating will
follow later in this series.
Link: https://lore.kernel.org/r/1f9cce7c829c881e7d71a3f10c5b57f3dd84ab32.1572018132.git.bblock@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
A new FCP channel feature allows us to read the diagnostics from our local
SFP transceivers. To make use of that add a flag
(FSF_FEATURE_REQUEST_SFP_DATA) to the feature-set we request from the FCP
channel. Whether the channel actually implements this can be determined via
an other new flag (FSF_FEATURE_REPORT_SFP_DATA), that is set in the
adapter_features field of the adapter structure after Exchange Config Data
finished.
Also add the corresponding definitions in the QTCB Bottom for Exchange Port
Data. These new definitions are only valid, if FSF_FEATURE_REPORT_SFP_DATA
is set.
Link: https://lore.kernel.org/r/ee1eba4de71eb06b4d82207ad4f428429346156f.1572018132.git.bblock@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
The FCP channel exposes two central interfaces to receive information about
the local FCP-Adapter/-Port: Exchange Port and Exchange Config Data. Using
these commands can negatively impact the adapter if we allow them to be
sent at a very high rate.
The later parts of this patchset will introduce new user-interfaces to
receive more diagnostics from the adapter. To prevent any negative impact
from using those, this patch adds a simple caching-mechanism that will
prevent a malicious/faulty userspace-application from generating an
abnormal high amount of Exchange Port/Config Data traffic.
Relevant diagnostic data that is received via Exchange Config/Port Data is
cached in buffers associated with the corresponding adapter-struct. Each
buffer is associated with a timestamp that signals how old the data is,
and, added via a following patch in this series, lets userspace-interfaces
determine when the data is too old and needs to be updated.
Buffer-updates are made during the normal response path of the
corresponding command. With this patch only the output of the Exchange Port
Data command is captured.
Link: https://lore.kernel.org/r/054ca020ce0a53dc0d9176428bea373898944e6a.1572018130.git.bblock@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Adds a new FSF-Request status flag (ZFCP_STATUS_FSFREQ_XDATAINCOMPLETE)
that signal that the data received using Exchange Config Data or Exchange
Port Data was incomplete. This new flags is set in the respective handlers
during the response path.
With this patch, only the synchronous FSF-functions for each command got
support for the new flag, otherwise it is transparent.
Together with this new flag and already existing status flags the
synchronous FSF-functions are extended to now detect whether the received
data is complete, incomplete or completely invalid (this includes cases
where a command ran into a timeout). This is now signaled back to the
caller, where previously only failures on the request path would result in
a bad return-code.
For complete data the return-code remains 0. For incomplete data a new
return-code -EAGAIN is added to the function-interface. For completely
invalid data the already existing return-code -EIO is reused - formerly
this was used to signal failures on the request path.
Existing callers of the FSF-functions are adjusted so that they behave as
before for return-code 0 and -EAGAIN, to not change the user-interface. As
-EIO existed all along, it was already exposed to the user - and needed
handling - and will now also be exposed in this new special case.
Link: https://lore.kernel.org/r/e14f0702fa2b00a4d1f37c7981a13f2dd1ea2c83.1572018130.git.bblock@linux.ibm.com
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
On excessive bit errors for the FCP channel ingress fibre path, the channel
notifies us. Previously, we only emitted a kernel message and a trace
record. Since performance can become suboptimal with I/O timeouts due to
bit errors, we now stop using an FCP device by default on channel
notification so multipath on top can timely failover to other paths. A new
module parameter zfcp.ber_stop can be used to get zfcp old behavior.
User explanation of new kernel message:
* Description:
* The FCP channel reported that its bit error threshold has been exceeded.
* These errors might result from a problem with the physical components
* of the local fibre link into the FCP channel.
* The problem might be damage or malfunction of the cable or
* cable connection between the FCP channel and
* the adjacent fabric switch port or the point-to-point peer.
* Find details about the errors in the HBA trace for the FCP device.
* The zfcp device driver closed down the FCP device
* to limit the performance impact from possible I/O command timeouts.
* User action:
* Check for problems on the local fibre link, ensure that fibre optics are
* clean and functional, and all cables are properly plugged.
* After the repair action, you can manually recover the FCP device by
* writing "0" into its "failed" sysfs attribute.
* If recovery through sysfs is not possible, set the CHPID of the device
* offline and back online on the service element.
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: <stable@vger.kernel.org> #2.6.30+
Link: https://lore.kernel.org/r/20191001104949.42810-1-maier@linux.ibm.com
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This is the final round of mostly small fixes in our initial submit.
It's mostly minor fixes and driver updates. The only change of note
is adding a virt_boundary_mask to the SCSI host and host template to
parametrise this for NVMe devices instead of having them do a call in
slave_alloc. It's a fairly straightforward conversion except in the
two NVMe handling drivers that didn't set it who now have a virtual
infinity parameter added.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI fixes from James Bottomley:
"This is the final round of mostly small fixes in our initial submit.
It's mostly minor fixes and driver updates. The only change of note is
adding a virt_boundary_mask to the SCSI host and host template to
parametrise this for NVMe devices instead of having them do a call in
slave_alloc. It's a fairly straightforward conversion except in the
two NVMe handling drivers that didn't set it who now have a virtual
infinity parameter added"
* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (24 commits)
scsi: megaraid_sas: set an unlimited max_segment_size
scsi: mpt3sas: set an unlimited max_segment_size for SAS 3.0 HBAs
scsi: IB/srp: set virt_boundary_mask in the scsi host
scsi: IB/iser: set virt_boundary_mask in the scsi host
scsi: storvsc: set virt_boundary_mask in the scsi host template
scsi: ufshcd: set max_segment_size in the scsi host template
scsi: core: take the DMA max mapping size into account
scsi: core: add a host / host template field for the virt boundary
scsi: core: Fix race on creating sense cache
scsi: sd_zbc: Fix compilation warning
scsi: libfc: fix null pointer dereference on a null lport
scsi: zfcp: fix GCC compiler warning emitted with -Wmaybe-uninitialized
scsi: zfcp: fix request object use-after-free in send path causing wrong traces
scsi: zfcp: fix request object use-after-free in send path causing seqno errors
scsi: megaraid_sas: Update driver version to 07.710.50.00
scsi: megaraid_sas: Add module parameter for FW Async event logging
scsi: megaraid_sas: Enable msix_load_balance for Invader and later controllers
scsi: megaraid_sas: Fix calculation of target ID
scsi: lpfc: reduce stack size with CONFIG_GCC_PLUGIN_STRUCTLEAK_VERBOSE
scsi: devinfo: BLIST_TRY_VPD_PAGES for SanDisk Cruzer Blade
...
GCC v9 emits this warning:
CC drivers/s390/scsi/zfcp_erp.o
drivers/s390/scsi/zfcp_erp.c: In function 'zfcp_erp_action_enqueue':
drivers/s390/scsi/zfcp_erp.c:217:26: warning: 'erp_action' may be used uninitialized in this function [-Wmaybe-uninitialized]
217 | struct zfcp_erp_action *erp_action;
| ^~~~~~~~~~
This is a possible false positive case, as also documented in the GCC
documentations:
https://gcc.gnu.org/onlinedocs/gcc/Warning-Options.html#index-Wmaybe-uninitialized
The actual code-sequence is like this:
Various callers can invoke the function below with the argument "want"
being one of:
ZFCP_ERP_ACTION_REOPEN_ADAPTER,
ZFCP_ERP_ACTION_REOPEN_PORT_FORCED,
ZFCP_ERP_ACTION_REOPEN_PORT, or
ZFCP_ERP_ACTION_REOPEN_LUN.
zfcp_erp_action_enqueue(want, ...)
...
need = zfcp_erp_required_act(want, ...)
need = want
...
maybe: need = ZFCP_ERP_ACTION_REOPEN_PORT
maybe: need = ZFCP_ERP_ACTION_REOPEN_ADAPTER
...
return need
...
zfcp_erp_setup_act(need, ...)
struct zfcp_erp_action *erp_action; // <== line 217
...
switch(need) {
case ZFCP_ERP_ACTION_REOPEN_LUN:
...
erp_action = &zfcp_sdev->erp_action;
WARN_ON_ONCE(erp_action->port != port); // <== access
...
break;
case ZFCP_ERP_ACTION_REOPEN_PORT:
case ZFCP_ERP_ACTION_REOPEN_PORT_FORCED:
...
erp_action = &port->erp_action;
WARN_ON_ONCE(erp_action->port != port); // <== access
...
break;
case ZFCP_ERP_ACTION_REOPEN_ADAPTER:
...
erp_action = &adapter->erp_action;
WARN_ON_ONCE(erp_action->port != NULL); // <== access
...
break;
}
...
WARN_ON_ONCE(erp_action->adapter != adapter); // <== access
When zfcp_erp_setup_act() is called, 'need' will never be anything else
than one of the 4 possible enumeration-names that are used in the
switch-case, and 'erp_action' is initialized for every one of them, before
it is used. Thus the warning is a false positive, as documented.
We introduce the extra if{} in the beginning to create an extra code-flow,
so the compiler can be convinced that the switch-case will never see any
other value.
BUG_ON()/BUG() is intentionally not used to not crash anything, should
this ever happen anyway - right now it's impossible, as argued above; and
it doesn't introduce a 'default:' switch-case to retain warnings should
'enum zfcp_erp_act_type' ever be extended and no explicit case be
introduced. See also v5.0 commit 399b6c8bc9 ("scsi: zfcp: drop old
default switch case which might paper over missing case").
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When tracing instances where we open and close WKA ports, we also pass the
request-ID of the respective FSF command.
But after successfully sending the FSF command we must not use the
request-object anymore, as this might result in an use-after-free (see
"zfcp: fix request object use-after-free in send path causing seqno
errors" ).
To fix this add a new variable that caches the request-ID before sending
the request. This won't change during the hand-off to the FCP channel,
and so it's safe to trace this cached request-ID later, instead of using
the request object.
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Fixes: d27a7cb919 ("zfcp: trace on request for open and close of WKA port")
Cc: <stable@vger.kernel.org> #2.6.38+
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
With a recent change to our send path for FSF commands we introduced a
possible use-after-free of request-objects, that might further lead to
zfcp crafting bad requests, which the FCP channel correctly complains
about with an error (FSF_PROT_SEQ_NUMB_ERROR). This error is then handled
by an adapter-wide recovery.
The following sequence illustrates the possible use-after-free:
Send Path:
int zfcp_fsf_open_port(struct zfcp_erp_action *erp_action)
{
struct zfcp_fsf_req *req;
...
spin_lock_irq(&qdio->req_q_lock);
// ^^^^^^^^^^^^^^^^
// protects QDIO queue during sending
...
req = zfcp_fsf_req_create(qdio,
FSF_QTCB_OPEN_PORT_WITH_DID,
SBAL_SFLAGS0_TYPE_READ,
qdio->adapter->pool.erp_req);
// ^^^^^^^^^^^^^^^^^^^
// allocation of the request-object
...
retval = zfcp_fsf_req_send(req);
...
spin_unlock_irq(&qdio->req_q_lock);
return retval;
}
static int zfcp_fsf_req_send(struct zfcp_fsf_req *req)
{
struct zfcp_adapter *adapter = req->adapter;
struct zfcp_qdio *qdio = adapter->qdio;
...
zfcp_reqlist_add(adapter->req_list, req);
// ^^^^^^^^^^^^^^^^
// add request to our driver-internal hash-table for tracking
// (protected by separate lock req_list->lock)
...
if (zfcp_qdio_send(qdio, &req->qdio_req)) {
// ^^^^^^^^^^^^^^
// hand-off the request to FCP channel;
// the request can complete at any point now
...
}
/* Don't increase for unsolicited status */
if (!zfcp_fsf_req_is_status_read_buffer(req))
// ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
// possible use-after-free
adapter->fsf_req_seq_no++;
// ^^^^^^^^^^^^^^^^
// because of the use-after-free we might
// miss this accounting, and as follow-up
// this results in the FCP channel error
// FSF_PROT_SEQ_NUMB_ERROR
adapter->req_no++;
return 0;
}
static inline bool
zfcp_fsf_req_is_status_read_buffer(struct zfcp_fsf_req *req)
{
return req->qtcb == NULL;
// ^^^^^^^^^
// possible use-after-free
}
Response Path:
void zfcp_fsf_reqid_check(struct zfcp_qdio *qdio, int sbal_idx)
{
...
struct zfcp_fsf_req *fsf_req;
...
for (idx = 0; idx < QDIO_MAX_ELEMENTS_PER_BUFFER; idx++) {
...
fsf_req = zfcp_reqlist_find_rm(adapter->req_list,
req_id);
// ^^^^^^^^^^^^^^^^^^^^
// remove request from our driver-internal
// hash-table (lock req_list->lock)
...
zfcp_fsf_req_complete(fsf_req);
}
}
static void zfcp_fsf_req_complete(struct zfcp_fsf_req *req)
{
...
if (likely(req->status & ZFCP_STATUS_FSFREQ_CLEANUP))
zfcp_fsf_req_free(req);
// ^^^^^^^^^^^^^^^^^
// free memory for request-object
else
complete(&req->completion);
// ^^^^^^^^
// completion notification for code-paths that wait
// synchronous for the completion of the request; in
// those the memory is freed separately
}
The result of the use-after-free only affects the send path, and can not
lead to any data corruption. In case we miss the sequence-number
accounting, because the memory was already re-purposed, the next FSF
command will fail with said FCP channel error, and we will recover the
whole adapter. This causes no additional errors, but it slows down
traffic. There is a slight chance of the same thing happen again
recursively after the adapter recovery, but so far this has not been seen.
This was seen under z/VM, where the send path might run on a virtual CPU
that gets scheduled away by z/VM, while the return path might still run,
and so create the necessary timing. Running with KASAN can also slow down
the kernel sufficiently to run into this user-after-free, and then see the
report by KASAN.
To fix this, simply pull the test for the sequence-number accounting in
front of the hand-off to the FCP channel (this information doesn't change
during hand-off), but leave the sequence-number accounting itself where it
is.
To make future regressions of the same kind less likely, add comments to
all closely related code-paths.
Signed-off-by: Benjamin Block <bblock@linux.ibm.com>
Fixes: f9eca02276 ("scsi: zfcp: drop duplicate fsf_command from zfcp_fsf_req which is also in QTCB header")
Cc: <stable@vger.kernel.org> #5.0+
Reviewed-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
This topic branch covers a fundamental change in how our sg lists are
allocated to make mq more efficient by reducing the size of the
preallocated sg list. This necessitates a large number of driver
changes because the previous guarantee that if a driver specified
SG_ALL as the size of its scatter list, it would get a non-chained
list and didn't need to bother with scatterlist iterators is now
broken and every driver *must* use scatterlist iterators.
This was broken out as a separate topic because we need to convert all
the drivers before pulling the trigger and unconverted drivers kept
being found, necessitating a rebase.
Signed-off-by: James E.J. Bottomley <jejb@linux.ibm.com>
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Merge tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Pull SCSI scatter-gather list updates from James Bottomley:
"This topic branch covers a fundamental change in how our sg lists are
allocated to make mq more efficient by reducing the size of the
preallocated sg list.
This necessitates a large number of driver changes because the
previous guarantee that if a driver specified SG_ALL as the size of
its scatter list, it would get a non-chained list and didn't need to
bother with scatterlist iterators is now broken and every driver
*must* use scatterlist iterators.
This was broken out as a separate topic because we need to convert all
the drivers before pulling the trigger and unconverted drivers kept
being found, necessitating a rebase"
* tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (21 commits)
scsi: core: don't preallocate small SGL in case of NO_SG_CHAIN
scsi: lib/sg_pool.c: clear 'first_chunk' in case of no preallocation
scsi: core: avoid preallocating big SGL for data
scsi: core: avoid preallocating big SGL for protection information
scsi: lib/sg_pool.c: improve APIs for allocating sg pool
scsi: esp: use sg helper to iterate over scatterlist
scsi: NCR5380: use sg helper to iterate over scatterlist
scsi: wd33c93: use sg helper to iterate over scatterlist
scsi: ppa: use sg helper to iterate over scatterlist
scsi: pcmcia: nsp_cs: use sg helper to iterate over scatterlist
scsi: imm: use sg helper to iterate over scatterlist
scsi: aha152x: use sg helper to iterate over scatterlist
scsi: s390: zfcp_fc: use sg helper to iterate over scatterlist
scsi: staging: unisys: visorhba: use sg helper to iterate over scatterlist
scsi: usb: image: microtek: use sg helper to iterate over scatterlist
scsi: pmcraid: use sg helper to iterate over scatterlist
scsi: ipr: use sg helper to iterate over scatterlist
scsi: mvumi: use sg helper to iterate over scatterlist
scsi: lpfc: use sg helper to iterate over scatterlist
scsi: advansys: use sg helper to iterate over scatterlist
...
Unlike the legacy I/O path, scsi-mq preallocates a large array to hold
the scatterlist for each request. This static allocation can consume
substantial amounts of memory on modern controllers which support a
large number of concurrently outstanding requests.
To facilitate a switch to a smaller static allocation combined with a
dynamic allocation for requests that need it, we need to make sure all
SCSI drivers handle chained scatterlists correctly.
Convert remaining drivers that directly dereference the scatterlist
array to using the iterator functions.
[mkp: clarified commit message]
Cc: Steffen Maier <maier@linux.ibm.com>
Cc: Benjamin Block <bblock@linux.ibm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: linux-s390@vger.kernel.org
Acked-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Signed-off-by: Ming Lei <ming.lei@redhat.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
When the user tries to remove a zfcp port via sysfs, we only rejected it if
there are zfcp unit children under the port. With purely automatically
scanned LUNs there are no zfcp units but only SCSI devices. In such cases,
the port_remove erroneously continued. We close the port and this
implicitly closes all LUNs under the port. The SCSI devices survive with
their private zfcp_scsi_dev still holding a reference to the "removed"
zfcp_port (still allocated but invisible in sysfs) [zfcp_get_port_by_wwpn
in zfcp_scsi_slave_alloc]. This is not a problem as long as the fc_rport
stays blocked. Once (auto) port scan brings back the removed port, we
unblock its fc_rport again by design. However, there is no mechanism that
would recover (open) the LUNs under the port (no "ersfs_3" without
zfcp_unit [zfcp_erp_strategy_followup_success]). Any pending or new I/O to
such LUN leads to repeated:
Done: NEEDS_RETRY Result: hostbyte=DID_IMM_RETRY driverbyte=DRIVER_OK
See also v4.10 commit 6f2ce1c6af ("scsi: zfcp: fix rport unblock race
with LUN recovery"). Even a manual LUN recovery
(echo 0 > /sys/bus/scsi/devices/H:C:T:L/zfcp_failed)
does not help, as the LUN links to the old "removed" port which remains
to lack ZFCP_STATUS_COMMON_RUNNING [zfcp_erp_required_act].
The only workaround is to first ensure that the fc_rport is blocked
(e.g. port_remove again in case it was re-discovered by (auto) port scan),
then delete the SCSI devices, and finally re-discover by (auto) port scan.
The port scan includes an fc_rport unblock, which in turn triggers
a new scan on the scsi target to freshly get new pure auto scan LUNs.
Fix this by rejecting port_remove also if there are SCSI devices
(even without any zfcp_unit) under this port. Re-use mechanics from v3.7
commit d99b601b63 ("[SCSI] zfcp: restore refcount check on port_remove").
However, we have to give up zfcp_sysfs_port_units_mutex earlier in unit_add
to prevent a deadlock with scsi_host scan taking shost->scan_mutex first
and then zfcp_sysfs_port_units_mutex now in our zfcp_scsi_slave_alloc().
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: b62a8d9b45 ("[SCSI] zfcp: Use SCSI device data zfcp scsi dev instead of zfcp unit")
Fixes: f8210e3488 ("[SCSI] zfcp: Allow midlayer to scan for LUNs when running in NPIV mode")
Cc: <stable@vger.kernel.org> #2.6.37+
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
With this early return due to zfcp_unit child(ren), we don't use the
zfcp_port reference from the earlier zfcp_get_port_by_wwpn() anymore and
need to put it.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: d99b601b63 ("[SCSI] zfcp: restore refcount check on port_remove")
Cc: <stable@vger.kernel.org> #3.7+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
If an incoming ELS of type RSCN contains more than one element, zfcp
suboptimally causes repeated erp trigger NOP trace records for each
previously failed port. These could be ports that went away. It loops over
each RSCN element, and for each of those in an inner loop over all
zfcp_ports.
The trigger to recover failed ports should be just the reception of some
RSCN, no matter how many elements it has. So we can loop over failed ports
separately, and only then loop over each RSCN element to handle the
non-failed ports.
The call chain was:
zfcp_fc_incoming_rscn
for (i = 1; i < no_entries; i++)
_zfcp_fc_incoming_rscn
list_for_each_entry(port, &adapter->port_list, list)
if (masked port->d_id match) zfcp_fc_test_link
if (!port->d_id) zfcp_erp_port_reopen "fcrscn1" <===
In order the reduce the "flooding" of the REC trace area in such cases, we
factor out handling the failed ports to be outside of the entries loop:
zfcp_fc_incoming_rscn
if (no_entries > 1) <===
list_for_each_entry(port, &adapter->port_list, list) <===
if (!port->d_id) zfcp_erp_port_reopen "fcrscn1" <===
for (i = 1; i < no_entries; i++)
_zfcp_fc_incoming_rscn
list_for_each_entry(port, &adapter->port_list, list)
if (masked port->d_id match) zfcp_fc_test_link
Abbreviated example trace records before this code change:
Tag : fcrscn1
WWPN : 0x500507630310d327
ERP want : 0x02
ERP need : 0x02
Tag : fcrscn1
WWPN : 0x500507630310d327
ERP want : 0x02
ERP need : 0x00 NOP => superfluous trace record
The last trace entry repeats if there are more than 2 RSCN elements.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Suppose more than one non-NPIV FCP device is active on the same channel.
Send I/O to storage and have some of the pending I/O run into a SCSI
command timeout, e.g. due to bit errors on the fibre. Now the error
situation stops. However, we saw FCP requests continue to timeout in the
channel. The abort will be successful, but the subsequent TUR fails.
Scsi_eh starts. The LUN reset fails. The target reset fails. The host
reset only did an FCP device recovery. However, for non-NPIV FCP devices,
this does not close and reopen ports on the SAN-side if other non-NPIV FCP
device(s) share the same open ports.
In order to resolve the continuing FCP request timeouts, we need to
explicitly close and reopen ports on the SAN-side.
This was missing since the beginning of zfcp in v2.6.0 history commit
ea127f975424 ("[PATCH] s390 (7/7): zfcp host adapter.").
Note: The FSF requests for forced port reopen could run into FSF request
timeouts due to other reasons. This would trigger an internal FCP device
recovery. Pending forced port reopen recoveries would get dismissed. So
some ports might not get fully reopened during this host reset handler.
However, subsequent I/O would trigger the above described escalation and
eventually all ports would be forced reopen to resolve any continuing FCP
request timeouts due to earlier bit errors.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 1da177e4c3 ("Linux-2.6.12-rc2")
Cc: <stable@vger.kernel.org> #3.0+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
An already deleted SCSI device can exist on the Scsi_Host and remain there
because something still holds a reference. A new SCSI device with the same
H:C:T:L and FCP device, target port WWPN, and FCP LUN can be created. When
we try to unblock an rport, we still find the deleted SCSI device and
return early because the zfcp_scsi_dev of that SCSI device is not
ZFCP_STATUS_COMMON_UNBLOCKED. Hence we miss to unblock the rport, even if
the new proper SCSI device would be in good state.
Therefore, skip deleted SCSI devices when iterating the sdevs of the shost.
[cf. __scsi_device_lookup{_by_target}() or scsi_device_get()]
The following abbreviated trace sequence can indicate such problem:
Area : REC
Tag : ersfs_3
LUN : 0x4045400300000000
WWPN : 0x50050763031bd327
LUN status : 0x40000000 not ZFCP_STATUS_COMMON_UNBLOCKED
Ready count : n not incremented yet
Running count : 0x00000000
ERP want : 0x01
ERP need : 0xc1 ZFCP_ERP_ACTION_NONE
Area : REC
Tag : ersfs_3
LUN : 0x4045400300000000
WWPN : 0x50050763031bd327
LUN status : 0x41000000
Ready count : n+1
Running count : 0x00000000
ERP want : 0x01
ERP need : 0x01
...
Area : REC
Level : 4 only with increased trace level
Tag : ertru_l
LUN : 0x4045400300000000
WWPN : 0x50050763031bd327
LUN status : 0x40000000
Request ID : 0x0000000000000000
ERP status : 0x01800000
ERP step : 0x1000
ERP action : 0x01
ERP count : 0x00
NOT followed by a trace record with tag "scpaddy"
for WWPN 0x50050763031bd327.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 6f2ce1c6af ("scsi: zfcp: fix rport unblock race with LUN recovery")
Cc: <stable@vger.kernel.org> #2.6.32+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
- A copy of Arnds compat wrapper generation series
- Pass information about the KVM guest to the host in form the control
program code and the control program version code
- Map IOV resources to support PCI physical functions on s390
- Add vector load and store alignment hints to improve performance
- Use the "jdd" constraint with gcc 9 to make jump labels working again
- Remove amode workaround for old z/VM releases from the DCSS code
- Add support for in-kernel performance measurements using the
CPU measurement counter facility
- Introduce a new PMU device cpum_cf_diag to capture counters and
store thenn as event raw data.
- Bug fixes and cleanups
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Merge tag 's390-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux
Pull s390 updates from Martin Schwidefsky:
- A copy of Arnds compat wrapper generation series
- Pass information about the KVM guest to the host in form the control
program code and the control program version code
- Map IOV resources to support PCI physical functions on s390
- Add vector load and store alignment hints to improve performance
- Use the "jdd" constraint with gcc 9 to make jump labels working again
- Remove amode workaround for old z/VM releases from the DCSS code
- Add support for in-kernel performance measurements using the CPU
measurement counter facility
- Introduce a new PMU device cpum_cf_diag to capture counters and store
thenn as event raw data.
- Bug fixes and cleanups
* tag 's390-5.1-1' of git://git.kernel.org/pub/scm/linux/kernel/git/s390/linux: (54 commits)
Revert "s390/cpum_cf: Add kernel message exaplanations"
s390/dasd: fix read device characteristic with CONFIG_VMAP_STACK=y
s390/suspend: fix prefix register reset in swsusp_arch_resume
s390: warn about clearing als implied facilities
s390: allow overriding facilities via command line
s390: clean up redundant facilities list setup
s390/als: remove duplicated in-place implementation of stfle
s390/cio: Use cpa range elsewhere within vfio-ccw
s390/cio: Fix vfio-ccw handling of recursive TICs
s390: vfio_ap: link the vfio_ap devices to the vfio_ap bus subsystem
s390/cpum_cf: Handle EBUSY return code from CPU counter facility reservation
s390/cpum_cf: Add kernel message exaplanations
s390/cpum_cf_diag: Add support for s390 counter facility diagnostic trace
s390/cpum_cf: add ctr_stcctm() function
s390/cpum_cf: move common functions into a separate file
s390/cpum_cf: introduce kernel_cpumcf_avail() function
s390/cpu_mf: replace stcctm5() with the stcctm() function
s390/cpu_mf: add store cpu counter multiple instruction support
s390/cpum_cf: Add minimal in-kernel interface for counter measurements
s390/cpum_cf: introduce kernel_cpumcf_alert() to obtain measurement alerts
...
There is no need to use void pointers, all drivers are in agreement
about the underlying data structure of the SBAL arrays.
Signed-off-by: Julian Wiedmann <jwi@linux.ibm.com>
Reviewed-by: Benjamin Block <bblock@linux.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Since v2.6.35 commit 683229845f ("[SCSI] zfcp: Report scatter-gather
limits to SCSI and block layer"), zfcp set dma_parms.max_segment_size ==
PAGE_SIZE (but without using the setter dma_set_max_seg_size()) and
scsi_host_template.dma_boundary == PAGE_SIZE - 1.
v5.0-rc1 commit 50c2e9107f ("scsi: introduce a max_segment_size
host_template parameters") introduced a new field
scsi_host_template.max_segment_size. If an LLDD such as zfcp does not set
it, scsi_host_alloc() uses BLK_MAX_SEGMENT_SIZE = 65536 for
Scsi_Host.max_segment_size. __scsi_init_queue() announced the minimum of
Scsi_Host.max_segment_size and dma_parms.max_segment_size to the block
layer. For zfcp: min(65536, 4096) == 4096 which was still good.
v5.0 commit a8cf59a669 ("scsi: communicate max segment size to the DMA
mapping code") announces Scsi_Host.max_segment_size to the block layer and
overwrites dma_parms.max_segment_size with Scsi_Host.max_segment_size. For
zfcp dma_parms.max_segment_size == Scsi_Host.max_segment_size == 65536
which is also reflected in block queue limits.
$ cd /sys/bus/ccw/drivers/zfcp
$ cd 0.0.3c40/host5/rport-5:0-4/target5:0:4/5:0:4:10/block/sdi/queue
$ cat max_segment_size
65536
Zfcp I/O still works because dma_boundary implicitly still keeps the
effective max segment size <= PAGE_SIZE. However, dma_boundary does not
seem visible to user space, but max_segment_size is visible and shows a
misleading wrong value. Fix it and inherit the stable tag of a8cf59a669.
Devices on our bus ccw support DMA but no DMA mapping. Of multiple device
types on the ccw bus, only zfcp needs dma_parms for SCSI limits. So, leave
dma_parms setup in zfcp and do not move it to the bus.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: 50c2e9107f ("scsi: introduce a max_segment_size host_template parameters")
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Most SCSI drivers want to enable "clustering", that is merging of
segments so that they might span more than a single page. Remove the
ENABLE_CLUSTERING define, and require drivers to explicitly set
DISABLE_CLUSTERING to disable this feature.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Complements
v2.6.35 commit 64deb6efdc ("[SCSI] zfcp: Use status_read_buf_num
provided by FCP channel") which replaced the hardcoded 16 with a
variable value
Also complements already existing fixups for above commit
v2.6.35 commit 8d88cf3f3b ("[SCSI] zfcp: Update status read mempool")
v3.10 commit 9edf7d75ee ("[SCSI] zfcp: status read buffers on first adapter open with link down")
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Suppose adapter (open) recovery is between opened QDIO queues and before
(the end of) initial posting of status read buffers (SRBs). This time
window can be seconds long due to FSF_PROT_HOST_CONNECTION_INITIALIZING
causing by design looping with exponential increase sleeps in the function
performing exchange config data during recovery
[zfcp_erp_adapter_strat_fsf_xconf()]. Recovery triggered by local link up.
Suppose an event occurs for which the FCP channel would send an unsolicited
notification to zfcp by means of a previously posted SRB. We saw it with
local cable pull (link down) in multi-initiator zoning with multiple
NPIV-enabled subchannels of the same shared FCP channel.
As soon as zfcp_erp_adapter_strategy_open_fsf() starts posting the initial
status read buffers from within the adapter's ERP thread, the channel does
send an unsolicited notification.
Since v2.6.27 commit d26ab06ede ("[SCSI] zfcp: receiving an unsolicted
status can lead to I/O stall"), zfcp_fsf_status_read_handler() schedules
adapter->stat_work to re-fill the just consumed SRB from a work item.
Now the ERP thread and the work item post SRBs in parallel. Both contexts
call the helper function zfcp_status_read_refill(). The tracking of
missing (to be posted / re-filled) SRBs is not thread-safe due to separate
atomic_read() and atomic_dec(), in order to depend on posting
success. Hence, both contexts can see
atomic_read(&adapter->stat_miss) == 1. One of the two contexts posts
one too many SRB. Zfcp gets QDIO_ERROR_SLSB_STATE on the output queue
(trace tag "qdireq1") leading to zfcp_erp_adapter_shutdown() in
zfcp_qdio_handler_error().
An obvious and seemingly clean fix would be to schedule stat_work from the
ERP thread and wait for it to finish. This would serialize all SRB
re-fills. However, we already have another work item wait on the ERP
thread: adapter->scan_work runs zfcp_fc_scan_ports() which calls
zfcp_fc_eval_gpn_ft(). The latter calls zfcp_erp_wait() to wait for all the
open port recoveries during zfcp auto port scan, but in fact it waits for
any pending recovery including an adapter recovery. This approach leads to
a deadlock. [see also v3.19 commit 18f87a67e6 ("zfcp: auto port scan
resiliency"); v2.6.37 commit d3e1088d68
("[SCSI] zfcp: No ERP escalation on gpn_ft eval");
v2.6.28 commit fca55b6fb5
("[SCSI] zfcp: fix deadlock between wq triggered port scan and ERP")
fixing v2.6.27 commit c57a39a45a
("[SCSI] zfcp: wait until adapter is finished with ERP during auto-port");
v2.6.27 commit cc8c282963
("[SCSI] zfcp: Automatically attach remote ports")]
Instead make the accounting of missing SRBs atomic for parallel execution
in both the ERP thread and adapter->stat_work.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Fixes: d26ab06ede ("[SCSI] zfcp: receiving an unsolicted status can lead to I/O stall")
Cc: <stable@vger.kernel.org> #2.6.27+
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Introduce separate zfcp module parameters to individually select support
for: DIF which should work (zfcp.dif, which used to be DIF+DIX, disabled)
or DIX+DIF which can cause trouble (zfcp.dix, new, disabled).
If DIX is enabled, we warn on zfcp driver initialization. As before, this
also reduces the maximum I/O request size to half, to support the worst
case of merged single sector requests with one protection data scatter
gather element per sector. This can impact the maximum throughput.
In DIF-only mode (zfcp.dif=1 zfcp.dix=0), we can use the full maximum I/O
request size as there is no protection data for zfcp.
Signed-off-by: Steffen Maier <maier@linux.ibm.com>
Signed-off-by: Fedor Loshakov <loshakov@linux.ibm.com>
Reviewed-by: Jens Remus <jremus@linux.ibm.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
