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* s390/qdio: fill SBALEs with absolute addressesJulian Wiedmann2020-02-193-7/+7
| | | | | | | | | 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>
* scsi: zfcp: trace channel log even for FCP command responsesSteffen Maier2019-10-291-5/+3
| | | | | | | | | | | | | | | | | 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: <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>
* scsi: zfcp: proper indentation to reduce confusion in zfcp_erp_required_actSteffen Maier2019-10-291-2/+2
| | | | | | | | | | | | | | 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>
* scsi: zfcp: move maximum age of diagnostic buffers into a per-adapter variableBenjamin Block2019-10-293-11/+61
| | | | | | | | | | | | | | | | | | | | 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>
* scsi: zfcp: implicitly refresh config-data diagnostics when reading sysfsBenjamin Block2019-10-293-0/+36
| | | | | | | | | | | | | | 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>
* scsi: zfcp: introduce sysfs interface to read the local B2B-CreditBenjamin Block2019-10-291-0/+40
| | | | | | | | | | | | | | | | 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>
* scsi: zfcp: implicitly refresh port-data diagnostics when reading sysfsBenjamin Block2019-10-293-0/+145
| | | | | | | | | | | | | | | | | 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>
* scsi: zfcp: introduce sysfs interface for diagnostics of local SFP transceiverBenjamin Block2019-10-295-0/+136
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* scsi: zfcp: support retrieval of SFP Data via Exchange Port DataBenjamin Block2019-10-292-3/+24
| | | | | | | | | | | | | | | | | | | 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>
* scsi: zfcp: add diagnostics buffer for exchange config dataBenjamin Block2019-10-293-2/+28
| | | | | | | | | | 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 <maier@linux.ibm.com> Signed-off-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: diagnostics buffer caching and use for exchange port dataBenjamin Block2019-10-296-3/+175
| | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* scsi: zfcp: signal incomplete or error for sync exchange config/port dataBenjamin Block2019-10-294-9/+46
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* scsi: zfcp: fix reaction on bit error threshold notificationSteffen Maier2019-10-041-3/+13
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: 1da177e4c3f4 ("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>
* Merge tag 'scsi-fixes' of ↵Linus Torvalds2019-07-202-7/+55
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * scsi: zfcp: fix GCC compiler warning emitted with -Wmaybe-uninitializedBenjamin Block2019-07-121-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 399b6c8bc9f7 ("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>
| * scsi: zfcp: fix request object use-after-free in send path causing wrong tracesBenjamin Block2019-07-121-2/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: d27a7cb91960 ("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>
| * scsi: zfcp: fix request object use-after-free in send path causing seqno errorsBenjamin Block2019-07-121-5/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: f9eca0227600 ("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>
* | Merge tag 'scsi-sg' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds2019-07-121-2/+2
|\| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * scsi: s390: zfcp_fc: use sg helper to iterate over scatterlistMing Lei2019-06-201-2/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* | scsi: zfcp: fix to prevent port_remove with pure auto scan LUNs (only sdevs)Steffen Maier2019-05-304-7/+65
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 6f2ce1c6af37 ("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 d99b601b6338 ("[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: b62a8d9b45b9 ("[SCSI] zfcp: Use SCSI device data zfcp scsi dev instead of zfcp unit") Fixes: f8210e34887e ("[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>
* | scsi: zfcp: fix missing zfcp_port reference put on -EBUSY from port_removeSteffen Maier2019-05-301-0/+1
|/ | | | | | | | | | | | | 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: d99b601b6338 ("[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>
* scsi: zfcp: reduce flood of fcrscn1 trace records on multi-element RSCNSteffen Maier2019-03-281-4/+17
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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>
* scsi: zfcp: fix scsi_eh host reset with port_forced ERP for non-NPIV FCP devicesSteffen Maier2019-03-283-0/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: 1da177e4c3f4 ("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>
* scsi: zfcp: fix rport unblock if deleted SCSI devices on Scsi_HostSteffen Maier2019-03-281-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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: 6f2ce1c6af37 ("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>
* Merge tag 's390-5.1-1' of ↵Linus Torvalds2019-03-051-2/+2
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 ...
| * s390/qdio: make SBAL address array type-safeJulian Wiedmann2019-02-071-2/+2
| | | | | | | | | | | | | | | | | | 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>
* | scsi: zfcp: fix sysfs block queue limit output for max_segment_sizeSteffen Maier2019-01-292-1/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Since v2.6.35 commit 683229845f17 ("[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 50c2e9107f17 ("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 a8cf59a6692c ("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 a8cf59a6692c. 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>
* scsi: flip the default on use_clusteringChristoph Hellwig2018-12-191-1/+0
| | | | | | | | | | 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>
* scsi: zfcp: improve kdoc for return of zfcp_status_read_refill()Steffen Maier2018-12-081-4/+4
| | | | | | | | | | | | | | | | | Complements v2.6.35 commit 64deb6efdc55 ("[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 8d88cf3f3b9a ("[SCSI] zfcp: Update status read mempool") v3.10 commit 9edf7d75ee5f ("[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>
* scsi: zfcp: fix posting too many status read buffers leading to adapter shutdownSteffen Maier2018-12-081-3/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | 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 d26ab06ede83 ("[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 18f87a67e6d6 ("zfcp: auto port scan resiliency"); v2.6.37 commit d3e1088d6873 ("[SCSI] zfcp: No ERP escalation on gpn_ft eval"); v2.6.28 commit fca55b6fb587 ("[SCSI] zfcp: fix deadlock between wq triggered port scan and ERP") fixing v2.6.27 commit c57a39a45a76 ("[SCSI] zfcp: wait until adapter is finished with ERP during auto-port"); v2.6.27 commit cc8c282963bd ("[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: d26ab06ede83 ("[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>
* scsi: zfcp: make DIX experimental, disabled, and independent of DIFFedor Loshakov2018-12-083-3/+11
| | | | | | | | | | | | | | | | | | | 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>
* scsi: zfcp: drop old default switch case which might paper over missing caseSteffen Maier2018-11-151-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | This was introduced with v2.6.27 commit 287ac01acf22 ("[SCSI] zfcp: Cleanup code in zfcp_erp.c") but would now suppress helpful -Wswitch compiler warnings when building with W=1 such as the following forced example: drivers/s390/scsi/zfcp_erp.c: In function 'zfcp_erp_setup_act': drivers/s390/scsi/zfcp_erp.c:220:2: warning: enumeration value 'ZFCP_ERP_ACTION_REOPEN_PORT' not handled in switch [-Wswitch] switch (need) { ^~~~~~ But then again, only with W=1 we would notice unhandled enum cases. Without the default cases and a missed unhandled enum case, the code might perform unforeseen things we might not want... As of today, we never run through the removed default case, so removing it is no functional change. In the future, we never should run through a default case but introduce the necessary specific case(s) to handle new functionality. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: drop default switch case which might paper over missing caseSteffen Maier2018-11-151-3/+0
| | | | | | | | | | | | | | | | | | | | | | | | | This was introduced with v4.18 commit 8c3d20aada70 ("scsi: zfcp: fix missing REC trigger trace for all objects in ERP_FAILED") but would now suppress helpful -Wswitch compiler warnings when building with W=1 such as the following forced example: drivers/s390/scsi/zfcp_erp.c: In function 'zfcp_erp_handle_failed': drivers/s390/scsi/zfcp_erp.c:126:2: warning: enumeration value 'ZFCP_ERP_ACTION_REOPEN_PORT_FORCED' not handled in switch [-Wswitch] switch (want) { ^~~~~~ But then again, only with W=1 we would notice unhandled enum cases. Without the default cases and a missed unhandled enum case, the code might perform unforeseen things we might not want... As of today, we never run through the removed default case, so removing it is no functional change. In the future, we never should run through a default case but introduce the necessary specific case(s) to handle new functionality. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: silence -Wimplicit-fallthrough in zfcp_erp_lun_strategy()Steffen Maier2018-11-151-1/+2
| | | | | | | | | | | | | | | | | | For some reason the already existing substring "fall through" in the comment is not sufficient for GCC to silence -Wimplicit-fallthrough. CC [M] drivers/s390/scsi/zfcp_erp.o drivers/s390/scsi/zfcp_erp.c: In function 'zfcp_erp_lun_strategy': drivers/s390/scsi/zfcp_erp.c:1065:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (atomic_read(&zfcp_sdev->status) & ZFCP_STATUS_COMMON_OPEN) ^ drivers/s390/scsi/zfcp_erp.c:1068:2: note: here case ZFCP_ERP_STEP_LUN_CLOSING: ^~~~ Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: silence remaining kdoc warnings in header filesSteffen Maier2018-11-155-9/+37
| | | | | | | | | | | | Improve whatever the following simple invocation reported: $ ./scripts/kernel-doc -none drivers/s390/scsi/*.h While at it, improve some related kdoc, including struct zfcp_fsf_ct_els in zfcp_fsf.h. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: silence all W=1 build warnings for existing kdocSteffen Maier2018-11-155-16/+22
| | | | | | | | While at it also improve some copy & paste kdoc mistakes. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: properly format LUN (and WWPN) for LUN sharing violation kmsgSteffen Maier2018-11-151-1/+1
| | | | | | | | | | | | | | | zfcp: <devbusid>: LUN 0x0 on port 0x5005076......... ... zfcp: <devbusid>: LUN 0x1000000000000 on port 0x5005076......... ... should be zfcp: <devbusid>: LUN 0x0000000000000000 on port 0x5005076......... ... zfcp: <devbusid>: LUN 0x0001000000000000 on port 0x5005076......... is already in use by CSS., MIF Image ID . Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: use enum zfcp_erp_act_result for argument/return of affected ↵Steffen Maier2018-11-151-40/+84
| | | | | | | | | | | | | | | | | | | | | | functions With that instead of just "int" it becomes clear which functions return this type and which ones also accept it as argument they just pass through in some cases or modify in other cases. v2.6.27 commit 287ac01acf22 ("[SCSI] zfcp: Cleanup code in zfcp_erp.c") introduced the enum which was cpp defines previously. Silence some false -Wswitch compiler warning cases with individual NOP cases. When adding more enum values and building with W=1 we would get compiler warnings about missed new cases. Consistently use the variable name "result", so change "retval" in zfcp_erp_strategy() to "result". This avoids confusion with other compile unit variables "retval" having different semantics and type. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: use enum zfcp_erp_steps for struct zfcp_erp_action.stepSteffen Maier2018-11-152-11/+40
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | Use the already defined enum for this purpose to get at least some build checking (even though an enum is type equivalent to an int in C). v2.6.27 commit 287ac01acf22 ("[SCSI] zfcp: Cleanup code in zfcp_erp.c") introduced the enum which was cpp defines previously. Since struct zfcp_erp_action type is embedded into other structures living in zfcp_def.h, we have to move enum zfcp_erp_act_type from its private definition in zfcp_erp.c to the zfcp-global zfcp_def.h Silence some false -Wswitch compiler warning cases with individual NOP cases. When adding more enum values and building with W=1 we would get compiler warnings about missed new cases. Add missing break statements in some of the above switch cases. No functional change, but making it future-proof. I think all of these should have had a break statement ever since, even if these switch cases happened to be the last ones in the switch statement body. "Fall through" in the context of switch case usually means not to have a break and fall through to the subsequent switch case. However, I think this old comment meant that here we do not have an _early return_ in the switch case but the code path continues after the switch case body. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: the action field of zfcp_erp_action is actually the typeSteffen Maier2018-11-153-43/+56
| | | | | | | | | | | | | | | | | | | | | | | &zfcp_erp_action.action ==> &zfcp_erp_action.type While at it, make use of the already defined enum for this purpose to get at least some build checking (even though an enum is type equivalent to an int in C). v2.6.27 commit 287ac01acf22 ("[SCSI] zfcp: Cleanup code in zfcp_erp.c") introduced the enum which was cpp defines previously. To prevent compiler warnings with the switch(act->type), we have to separate the recently added eyecatchers from enum zfcp_erp_act_type. Since struct zfcp_erp_action type is embedded into other structures living in zfcp_def.h, we have to move enum zfcp_erp_act_type from its private definition in zfcp_erp.c to the zfcp-global zfcp_def.h. Silence one false -Wswitch compiler warning case: LUNs as the leaves in our object tree do not have any follow-up success recovery. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: clarify function argument name for trace tag stringSteffen Maier2018-11-153-51/+57
| | | | | | | | | | | | | | | | | | | | | v2.6.30 commit 5ffd51a5e495 ("[SCSI] zfcp: replace current ERP logging with a more convenient version") changed trace record distinguishing from a numerical ID to a 7 character string called "trace tag". While starting to use function arguments with different type and semantics, it did not change the argument name accordingly. v2.6.38 commit ae0904f60fab ("[SCSI] zfcp: Redesign of the debug tracing for recovery actions.") renamed variable names "id" into "tag" but only within zfcp_dbf.*, not within zfcp_erp.c. This was a bit confusing since the remainder of zfcp does use the term "trace tag". Also "id" is quite generic and it's not obvious for what. Just unify it consistently and use the "dbf" prefix to relate the arguments to the code in zfcp_dbf.*. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: ERP thread setup kdoc updateSteffen Maier2018-11-151-1/+1
| | | | | | | | | zfcp_erp_thread_setup() update complements v2.6.32 commit 347c6a965dc1 ("[SCSI] zfcp: Use kthread API for zfcp erp thread"). Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: update kernel message for invalid FCP_CMND length, it's not the CDBSteffen Maier2018-11-151-5/+2
| | | | | | | | | The CDB is just a part inside of FCP_CMND, see zfcp_fc_scsi_to_fcp(). While at it, fix the device driver reaction: adapter not LUN shutdown. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: drop duplicate seq_no from zfcp_fsf_req which is also in QTCB headerSteffen Maier2018-11-153-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no point for double bookkeeping especially just for tracing. The trace can take it from the QTCB which always exists for non-SRB responses traced with zfcp_dbf_hba_fsf_res(). As a side effect, this removes an alignment hole and reduces the size of struct zfcp_fsf_req, and thus of each pending request, by 8 bytes. Before: $ pahole -C zfcp_fsf_req drivers/s390/scsi/zfcp.ko ... struct fsf_qtcb * qtcb; /* 144 8 */ u32 seq_no; /* 152 4 */ /* XXX 4 bytes hole, try to pack */ void * data; /* 160 8 */ ... /* size: 296, cachelines: 2, members: 14 */ /* sum members: 288, holes: 2, sum holes: 8 */ /* last cacheline: 40 bytes */ After: $ pahole -C zfcp_fsf_req drivers/s390/scsi/zfcp.ko ... struct fsf_qtcb * qtcb; /* 144 8 */ void * data; /* 152 8 */ ... /* size: 288, cachelines: 2, members: 13 */ /* sum members: 284, holes: 1, sum holes: 4 */ Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: drop duplicate fsf_command from zfcp_fsf_req which is also in ↵Steffen Maier2018-11-155-17/+20
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | QTCB header Status read buffers (SRBs, unsolicited notifications) never use a QTCB [zfcp_fsf_req_create()]. zfcp_fsf_req_send() already uses this to distinguish SRBs from other FSF request types. We can re-use this method in zfcp_fsf_req_complete(). Introduce a helper function to make the check for req->qtcb less magic. SRBs always are FSF_QTCB_UNSOLICITED_STATUS, so we can hard-code this for the two trace functions dealing with SRBs. All other FSF request types have a QTCB and we can get the fsf_command from there. zfcp_dbf_hba_fsf_response() and thus zfcp_dbf_hba_fsf_res() are only called for non-SRB requests so it's safe to dereference the QTCB [zfcp_fsf_req_complete() returns early on SRB, else calls zfcp_fsf_protstatus_eval() which calls zfcp_dbf_hba_fsf_response()]. In zfcp_scsi_forget_cmnd() we guard the QTCB dereference with a preceding NULL check and rely on boolean shortcut evaluation. As a side effect, this causes an alignment hole which we can close in a later patch after having cleaned up all fields of struct zfcp_fsf_req. Before: $ pahole -C zfcp_fsf_req drivers/s390/scsi/zfcp.ko ... u32 status; /* 136 4 */ u32 fsf_command; /* 140 4 */ struct fsf_qtcb * qtcb; /* 144 8 */ ... After: $ pahole -C zfcp_fsf_req drivers/s390/scsi/zfcp.ko ... u32 status; /* 136 4 */ /* XXX 4 bytes hole, try to pack */ struct fsf_qtcb * qtcb; /* 144 8 */ ... Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: drop unnecessary forward prototype for struct zfcp_fsf_reqSteffen Maier2018-11-151-2/+0
| | | | | | Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: group sort internal structure definitions for proximitySteffen Maier2018-11-151-29/+29
| | | | | | | | | | | | | | Have structures just before the structures that use them (without disrupting sequences of using structures such as zfcp_unit and zfcp_scsi_dev): - zfcp_adapter_mempool embedded in zfcp_adapter, - zfcp_latenc... embedded in zfcp_scsi_dev. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: namespace prefix for internal latency data structuresSteffen Maier2018-11-152-9/+9
| | | | | | | | | In contrast to struct fsf_qual_latency_info, the ones here are not FSF but software defined zfcp-internal. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: update width in comment for ZFCP_COMMON_FLAGS maskSteffen Maier2018-11-151-2/+2
| | | | | | | | | | | v2.6.10 history commit 4062e12b2ba2 ("[PATCH] s390: zfcp act enhancements") extended this mask by one nibble with the introduction of ZFCP_STATUS_COMMON_ACCESS_DENIED == 0x00800000 for ACT (access control table). Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
* scsi: zfcp: move scsi_eh & non-ERP timeout defines owned by and local to ↵Steffen Maier2018-11-152-8/+7
| | | | | | | | | | | zfcp_fsf.c Also clarify namespace prefix for the timeout used for FSF requests on behalf of SCSI error recovery: It is zfcp_fsf_ not zfcp_scsi_. Signed-off-by: Steffen Maier <maier@linux.ibm.com> Reviewed-by: Benjamin Block <bblock@linux.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>