talos-op-linux/drivers/s390/scsi, branch master

scsi: zfcp: trace channel log even for FCP command responses

2019-10-29T02:16:15+00:00

While v2.6.26 commit b75db73159cc ("[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: b75db73159cc ("[SCSI] zfcp: Add qtcb dump to hba debug trace") Fixes: a54ca0f62f95 ("[SCSI] zfcp: Redesign of the debug tracing for HBA records.") Cc: #2.6.38+ Link: https://lore.kernel.org/r/e37597b5c4ae123aaa85fd86c23a9f71e994e4a9.1572018132.git.bblock@linux.ibm.com Reviewed-by: Benjamin Block Signed-off-by: Steffen Maier Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: proper indentation to reduce confusion in zfcp_erp_required_act

2019-10-29T02:16:15+00:00

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 Reviewed-by: Benjamin Block Signed-off-by: Steffen Maier Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: move maximum age of diagnostic buffers into a per-adapter variable

2019-10-29T02:16:15+00:00

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 Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: implicitly refresh config-data diagnostics when reading sysfs

2019-10-29T02:16:15+00:00

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 Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: introduce sysfs interface to read the local B2B-Credit

2019-10-29T02:16:15+00:00

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 Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: implicitly refresh port-data diagnostics when reading sysfs

2019-10-29T02:16:15+00:00

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 Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: introduce sysfs interface for diagnostics of local SFP transceiver

2019-10-29T02:16:15+00:00

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 Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: support retrieval of SFP Data via Exchange Port Data

2019-10-29T02:16:15+00:00

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 Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: add diagnostics buffer for exchange config data

2019-10-29T02:16:14+00:00

In the same vein as the previous patch, add diagnostic data capture for the Exchange Config Data command. Link: https://lore.kernel.org/r/7d8ac0a6cad403fa8f8b888693476a84e80a277b.1572018131.git.bblock@linux.ibm.com Reviewed-by: Steffen Maier Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen

scsi: zfcp: diagnostics buffer caching and use for exchange port data

2019-10-29T02:16:14+00:00

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 Signed-off-by: Benjamin Block Signed-off-by: Martin K. Petersen