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* scsi: cxlflash: Improve EEH recovery timeMatthew R. Ochs2017-05-08
| | | | | | | | | | | | | | | | | | | | | commit 05dab43230fdc0d14ca885b473a2740fe017ecb1 upstream. When an EEH occurs during device initialization, the port timeout logic can cause excessive delays as MMIO reads will fail. Depending on where they are experienced, these delays can lead to a prolonged reset, causing an unnecessary triggering of other timeout logic in the SCSI stack or user applications. To expedite recovery, the port timeout logic is updated to decay the timeout at a much faster rate when in the presence of a likely EEH frozen event. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* scsi: cxlflash: Fix to avoid EEH and host reset collisionsMatthew R. Ochs2017-05-08
| | | | | | | | | | | | | | | | | | | | | | | | | | commit 1d3324c382b1a617eb567e3650dcb51f22dfec9a upstream. The EEH reset handler is ignorant to the current state of the driver when processing a frozen event and initiating a device reset. This can be an issue if an EEH event occurs while a user or stack initiated reset is executing. More specifically, if an EEH occurs while the SCSI host reset handler is active, the reset initiated by the EEH thread will likely collide with the host reset thread. This can leave the device in an inconsistent state, or worse, cause a system crash. As a remedy, the EEH handler is updated to evaluate the device state and take appropriate action (proceed, wait, or disconnect host). The host reset handler is also updated to handle situations where an EEH occurred during a host reset. In such situations, the host reset handler will delay reporting back a success to give the EEH reset an opportunity to complete. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* scsi: cxlflash: Scan host only after the port is ready for I/OUma Krishnan2017-05-08
| | | | | | | | | | | | | | | | | | | | | | | | | | | commit bbbfae962b7c221237c0f92547ee0c83f7204747 upstream. When a port link is established, the AFU sends a 'link up' interrupt. After the link is up, corresponding initialization steps are performed on the card. Following that, when the card is ready for I/O, the AFU sends 'login succeeded' interrupt. Today, cxlflash invokes scsi_scan_host() upon receipt of both interrupts. SCSI commands sent to the port prior to the 'login succeeded' interrupt will fail with 'port not available' error. This is not desirable. Moreover, when async_scan is active for the host, subsequent scan calls are terminated with error. Due to this, the scsi_scan_host() call performed after 'login succeeded' interrupt could portentially return error and the devices may not be scanned properly. To avoid this problem, scsi_scan_host() should be called only after the 'login succeeded' interrupt. Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Increase cmd_per_lun for better throughputManoj N. Kumar2017-03-26
| | | | | | | | | | | | | | | | | | | | commit 83430833b4d4a9c9b23964babbeb1f36450f8136 upstream. With the current value of cmd_per_lun at 16, the throughput over a single adapter is limited to around 150kIOPS. Increase the value of cmd_per_lun to 256 to improve throughput. With this change a single adapter is able to attain close to the maximum throughput (380kIOPS). Also change the number of RRQ entries that can be queued. Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Cc: Sumit Semwal <sumit.semwal@linaro.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Move to exponential back-off when cmd_room is not availableManoj N. Kumar2016-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit ea76543127da32dec28af0a13ea1b06625fc085e ] While profiling the cxlflash_queuecommand() path under a heavy load it was found that number of retries to find cmd_room was fairly high. There are two problems with the current back-off: a) It starts with a udelay of 0 b) It backs-off linearly Tried several approaches (a higher multiple 10*n, 100*n, as well as n^2, 2^n) and found that the exponential back-off(2^n) approach had the least overall cost. Cost as being defined as overall time spent waiting. The fix is to change the linear back-off to an exponential back-off. This solution also takes care of the problem with the initial delay (starts with 1 usec). Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Fix to avoid virtual LUN failover failureMatthew R. Ochs2016-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit d5e26bb1d812ba74f29b6bcbc88c3dbfb3eed824 ] Applications which use virtual LUN's that are backed by a physical LUN over both adapter ports may experience an I/O failure in the event of a link loss (e.g. cable pull). Virtual LUNs may be accessed through one or both ports of the adapter. This access is encoded in the translation entries that comprise the virtual LUN and used by the AFU for load-balancing I/O and handling failover scenarios. In a link loss scenario, even though the AFU is able to maintain connectivity to the LUN, it is up to the application to retry the failed I/O. When applications are unaware of the virtual LUN's underlying topology, they are unable to make a sound decision of when to retry an I/O and therefore are forced to make their reaction to a failed I/O absolute. The result is either a failure to retry I/O or increased latency for scenarios where a retry is pointless. To remedy this scenario, provide feedback back to the application on virtual LUN creation as to which ports the LUN may be accessed. LUN's spanning both ports are candidates for a retry in a presence of an I/O failure. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Fix to escalate LINK_RESET also on port 1Manoj Kumar2016-09-15
| | | | | | | | | | | | | | | [ Upstream commit a9be294ecb3b9dc82b15625631b153f871181d16 ] The original fix to escalate a 'login timed out' error to a LINK_RESET was only made for one of the two ports on the card. This fix resolves the same issue for the second port (port 1). Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Fix to resolve dead-lock during EEH recoveryManoj N. Kumar2016-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 635f6b0893cff193a1774881ebb1e4a4b9a7fead ] When a cxlflash adapter goes into EEH recovery and multiple processes (each having established its own context) are active, the EEH recovery can hang if the processes attempt to recover in parallel. The symptom logged after a couple of minutes is: INFO: task eehd:48 blocked for more than 120 seconds. Not tainted 4.5.0-491-26f710d+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. eehd 0 48 2 Call Trace: __switch_to+0x2f0/0x410 __schedule+0x300/0x980 schedule+0x48/0xc0 rwsem_down_write_failed+0x294/0x410 down_write+0x88/0xb0 cxlflash_pci_error_detected+0x100/0x1c0 [cxlflash] cxl_vphb_error_detected+0x88/0x110 [cxl] cxl_pci_error_detected+0xb0/0x1d0 [cxl] eeh_report_error+0xbc/0x130 eeh_pe_dev_traverse+0x94/0x160 eeh_handle_normal_event+0x17c/0x450 eeh_handle_event+0x184/0x370 eeh_event_handler+0x1c8/0x1d0 kthread+0x110/0x130 ret_from_kernel_thread+0x5c/0xa4 INFO: task blockio:33215 blocked for more than 120 seconds. Not tainted 4.5.0-491-26f710d+ #1 "echo 0 > /proc/sys/kernel/hung_task_timeout_secs" disables this message. blockio 0 33215 33213 Call Trace: 0x1 (unreliable) __switch_to+0x2f0/0x410 __schedule+0x300/0x980 schedule+0x48/0xc0 rwsem_down_read_failed+0x124/0x1d0 down_read+0x68/0x80 cxlflash_ioctl+0x70/0x6f0 [cxlflash] scsi_ioctl+0x3b0/0x4c0 sg_ioctl+0x960/0x1010 do_vfs_ioctl+0xd8/0x8c0 SyS_ioctl+0xd4/0xf0 system_call+0x38/0xb4 INFO: task eehd:48 blocked for more than 120 seconds. The hang is because of a 3 way dead-lock: Process A holds the recovery mutex, and waits for eehd to complete. Process B holds the semaphore and waits for the recovery mutex. eehd waits for semaphore. The fix is to have Process B above release the semaphore before attempting to acquire the recovery mutex. This will allow eehd to proceed to completion. Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Fix to avoid unnecessary scan with internal LUNsManoj N. Kumar2016-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit 603ecce95f4817074a724a889cd88c3c8210f933 ] When switching to the internal LUN defined on the IBM CXL flash adapter, there is an unnecessary scan occurring on the second port. This scan leads to the following extra lines in the log: Dec 17 10:09:00 tul83p1 kernel: [ 3708.561134] cxlflash 0008:00:00.0: cxlflash_queuecommand: (scp=c0000000fc1f0f00) 11/1/0/0 cdb=(A0000000-00000000-10000000-00000000) Dec 17 10:09:00 tul83p1 kernel: [ 3708.561147] process_cmd_err: cmd failed afu_rc=32 scsi_rc=0 fc_rc=0 afu_extra=0xE, scsi_extra=0x0, fc_extra=0x0 By definition, both of the internal LUNs are on the first port/channel. When the lun_mode is switched to internal LUN the same value for host->max_channel is retained. This causes an unnecessary scan over the second port/channel. This fix alters the host->max_channel to 0 (1 port), if internal LUNs are configured and switches it back to 1 (2 ports) while going back to external LUNs. Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Enable device id for future IBM CXL adapterManoj Kumar2016-09-15
| | | | | | | | | | | | | | | | | | | | | | [ Upstream commit a2746fb16e41b7c8f02aa4d2605ecce97abbebbd ] This drop enables a future card with a device id of 0x0600 to be recognized by the cxlflash driver. As per the design, the Accelerator Function Unit (AFU) for this new IBM CXL Flash Adapter retains the same host interface as the previous generation. For the early prototypes of the new card, the driver with this change behaves exactly as the driver prior to this behaved with the earlier generation card. Therefore, no card specific programming has been added. These card specific changes can be staged in later if needed. Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Resolve oops in wait_port_offlineManoj Kumar2016-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit b45cdbaf9f7f0486847c52f60747fb108724652a ] If an async error interrupt is generated, and the error requires the FC link to be reset, it cannot be performed in the interrupt context. So a work element is scheduled to complete the link reset in a process context. If either an EEH event or an escalation occurs in between when the interrupt is generated and the scheduled work is started, the MMIO space may no longer be available. This will cause an oops in the worker thread. [ 606.806583] NIP kthread_data+0x28/0x40 [ 606.806633] LR wq_worker_sleeping+0x30/0x100 [ 606.806694] Call Trace: [ 606.806721] 0x50 (unreliable) [ 606.806796] wq_worker_sleeping+0x30/0x100 [ 606.806884] __schedule+0x69c/0x8a0 [ 606.806959] schedule+0x44/0xc0 [ 606.807034] do_exit+0x770/0xb90 [ 606.807109] die+0x300/0x460 [ 606.807185] bad_page_fault+0xd8/0x150 [ 606.807259] handle_page_fault+0x2c/0x30 [ 606.807338] wait_port_offline.constprop.12+0x60/0x130 [cxlflash] To prevent the problem space area from being unmapped, when there is pending work, a mapcount (using the kref mechanism) is held. The mapcount is released only when the work is completed. The last reference release is tied to the unmapping service. Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Fix to resolve cmd leak after host resetManoj Kumar2016-09-15
| | | | | | | | | | | | | | | | | | | | | | | | | | | [ Upstream commit ee91e332a6e6e9b939f60f6e1bd72fb2def5290d ] After a few iterations of resetting the card, either during EEH recovery, or a host_reset the following is seen in the logs. cxlflash 0008:00: cxlflash_queuecommand: could not get a free command At every reset of the card, the commands that are outstanding are being leaked. No effort is being made to reap these commands. A few more resets later, the above error message floods the logs and the card is rendered totally unusable as no free commands are available. Iterated through the 'cmd' queue and printed out the 'free' counter and found that on each reset certain commands were in-use and stayed in-use through subsequent resets. To resolve this issue, when the card is reset, reap all the commands that are active/outstanding. Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: a couple off by one bugsDan Carpenter2016-09-15
| | | | | | | | | | | | | | | [ Upstream commit e37390bee6fe7dfbe507a9d50cdc11344b53fa08 ] The "> MAX_CONTEXT" should be ">= MAX_CONTEXT". Otherwise we go one step beyond the end of the cfg->ctx_tbl[] array. Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com> Reviewed-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> Signed-off-by: Sasha Levin <alexander.levin@verizon.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
* cxlflash: Fix to avoid bypassing context cleanupMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Contexts may be skipped over for cleanup in situations where contention for the adapter's table-list mutex is experienced in the presence of a signal during the execution of the release handler. This can lead to two known issues: - A hang condition on remove as that path tries to wait for users to cleanup - something that will never complete should this scenario play out as the user has already cleaned up from their perspective. - An Oops in the unmap_mapping_range() call that is made as part of the user waiting mechanism that is invoked on remove when contexts are found to still exist. The root cause of this issue can be found in get_context() and how the table-list mutex is acquired. As this code path is shared by several different access points within the driver, a decision was made during the development cycle to acquire this mutex in this location using the interruptible version of the mutex locking service. In almost all of the use-cases and environmental scenarios this holds up, even when the mutex is contended. However, for critical system threads (such as the release handler), failing to acquire the mutex and bailing with the intention of the user being able to try again later is unacceptable. In such a scenario, the context _must_ be derived as it is on an irreversible path to being freed. Without being able to derive the context, the code mistakenly assumes that it has already been freed and proceeds to free up the underlying CXL context resources. From this point on, any usage of [the now stale] CXL context resources will result in undefined behavior. This is root cause of the Oops mentioned as the second known issue as the mapping passed to the unmap_mapping_range() service is owned by the CXL context. To fix this problem, acquisition of the table-list mutex within get_context() is simply changed to use the uninterruptible version of the mutex locking service. This is safe as the timing windows for holding this mutex are short and also protected against blocking. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid lock instrumentation rejectionMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | When running with lock instrumentation (e.g. lockdep), some of the instrumentation can become disabled at probe time for a cxlflash adapter. This is due to a missing lock registration for the tmf_slock. The fix is to call spin_lock_init() for the tmf_slock during probe. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid corrupting port selection maskMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The port selection mask of a LUN can be corrupted when the manage LUN ioctl (DK_CXLFLASH_MANAGE_LUN) is issued more than once for any device. This mask indicates to the AFU which port[s] can be used for a data transfer to/from a particular LUN. The mask is critical to ensuring the correct behavior when using the virtual LUN function of this adapter. When the mask is configured for both ports, an I/O may be sent to either port as the AFU assumes that each port has access to the same physical device (specified by LUN ID in the port LUN table). In a situation where the mask becomes incorrectly configured to reflect access to both ports when in fact there is only access through a single port, an I/O can be targeted to the wrong physical device. This can lead to data corruption among other ill effects (e.g. security leaks). The cause for this corruption is the assumption that the ioctl will only be called a second time for a LUN when it is being configured for access via a second port. A boolean 'newly_created' variable is used to differentiate between a LUN that was created (and subsequently configured for single port access) and one that is destined for access across both ports. While initially set to 'true', this sticky boolean is toggled to the 'false' state during a lookup on any next ioctl performed on a device with a matching WWN/WWID. The code fails to realize that the match could in fact be the same device calling in again. From here, an assumption is made that any LUN with 'newly_created' set to 'false' is configured for access over both ports and the port selection mask is set to reflect this. Any future attempts to use this LUN for hosting a virtual LUN will result in the port LUN table being incorrectly programmed. As a remedy, the 'newly_created' concept was removed entirely and replaced with code that always constructs the port selection mask based upon the SCSI channel of the LUN being accessed. The bits remain sticky, therefore allowing for a device to be accessed over both ports when that is in fact the correct physical configuration. Also included in this commit are a few minor related changes to enhance the fix and provide better debug information for port selection mask and port LUN table bugs in the future. These include renaming refresh_local() to lookup_local(), tracing the WWN/WWID as a big-endian entity, and tracing the port selection mask, SCSI channel, and LUN ID each time the port LUN table is programmed. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to escalate to LINK_RESET on login timeoutManoj Kumar2015-10-30
| | | | | | | | | | | | | A 'login timed out' asynchronous error interrupt is generated if no response is seen to a FLOGI within 2 seconds. If the time out error is not escalated to a LINK_RESET the port will not be available for use. This fix provides the required escalation. Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid leaving dangling interrupt resourcesMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | When running with an unsupported AFU, the cxlflash driver fails the probe. When the driver is removed, the following Oops is encountered on a show_interrupts() thread: Call Trace: [c000001fba5a7a10] [0000000000000003] 0x3 (unreliable) [c000001fba5a7a60] [c00000000053dcf4] vsnprintf+0x204/0x4c0 [c000001fba5a7ae0] [c00000000030045c] seq_vprintf+0x5c/0xd0 [c000001fba5a7b20] [c00000000030051c] seq_printf+0x4c/0x60 [c000001fba5a7b50] [c00000000013e140] show_interrupts+0x370/0x4f0 [c000001fba5a7c10] [c0000000002ff898] seq_read+0xe8/0x530 [c000001fba5a7ca0] [c00000000035d5c0] proc_reg_read+0xb0/0x110 [c000001fba5a7cf0] [c0000000002ca74c] __vfs_read+0x6c/0x180 [c000001fba5a7d90] [c0000000002cb464] vfs_read+0xa4/0x1c0 [c000001fba5a7de0] [c0000000002cc51c] SyS_read+0x6c/0x110 [c000001fba5a7e30] [c000000000009204] system_call+0x38/0xb4 The Oops is due to not cleaning up correctly on the unsupported AFU error path, leaving various allocated and registered resources. In this case, interrupts are in a semi-allocated/registered state, which the show_interrupts() thread attempts to use. To fix, the cleanup logic in init_afu() is consolidated to error gates at the bottom of the function and the appropriate goto is added to each error path. As a mini side fix while refactoring in this routine, the else statement following the AFU version evaluation is eliminated as it is not needed. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid potential deadlock on EEHMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Ioctl threads that use scsi_execute() can run for an excessive amount of time due to the fact that they have lengthy timeouts and retry logic built in. Under normal operation this is not an issue. However, once EEH enters the picture, a long execution time coupled with the possibility that a timeout can trigger entry to the driver via registered reset callbacks becomes a liability. In particular, a deadlock can occur when an EEH event is encountered while in running in scsi_execute(). As part of the recovery, the EEH handler drains all currently running ioctls, waiting until they have completed before proceeding with a reset. As the scsi_execute()'s are situated on the ioctl path, the EEH handler will wait until they (and the remainder of the ioctl handler they're associated with) have completed. Normally this would not be much of an issue aside from the longer recovery period. Unfortunately, the scsi_execute() triggers a reset when it times out. The reset handler will see that the device is already being reset and wait until that reset completed. This creates a condition where the EEH handler becomes stuck, infinitely waiting for the ioctl thread to complete. To avoid this behavior, temporarily unmark the scsi_execute() threads as an ioctl thread by releasing the ioctl read semaphore. This allows the EEH handler to proceed with a recovery while the thread is still running. Once the scsi_execute() returns, the ioctl read semaphore is reacquired and the adapter state is rechecked in case it changed while inside of scsi_execute(). The state check will wait if the adapter is still being recovered or returns a failure if the recovery failed. In the event that the adapter reset failed, the failure is simply returned as the ioctl would be unable to continue. Reported-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Correct trace stringMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | The trace following the failure of alloc_mem() incorrectly identifies which function failed. This can lead to misdiagnosing a failure. Fix the string to correctly indicate that alloc_mem() failed. Reported-by: Brian King <brking@linux.vnet.ibm.com> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid corrupting adapter fopsMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The fops owned by the adapter can be corrupted in certain scenarios, opening a window where certain fops are temporarily NULLed before being reset to their proper value. This can potentially lead software to make incorrect decisions, leaving the user with the inability to function as intended. An example of this behavior can be observed when there are a number of users with a high rate of turn around (attach to LUN, perform an I/O, detach from LUN, repeat). Every so often a user is given a valid context and adapter file descriptor, but the file associated with the descriptor lacks the correct read permission bit (FMODE_CAN_READ) and thus the read system call bails before calling the valid read fop. Background: The fops is stored in the adapter structure to provide the ability to lookup the adapter structure from within the fop handler. CXL services use the file's private_data and at present, the CXL context does not have a private section. In an effort to limit areas of the cxlflash driver with code specific the superpipe function, a design choice was made to keep the details of the fops situated away from the legacy portions of the driver. This drove the behavior that the adapter fops is set at the beginning of the disk attach ioctl handler when there are no users present. The corruption that this fix remedies is due to the fact that the fops is initially defaulted to values found within a static structure. When the fops is handed down to the CXL services later in the attach path, certain services are patched. The fops structure remains correct until the user count drops to 0 and the fops is reset, triggering the process to repeat again. The user counts are tightly coupled with the creation and deletion of the user context. If multiple users perform a disk attach at the same time, when the user count is currently 0, some users can be in the middle of obtaining a file descriptor and have not yet reached the context creation code that [in addition to creating the context] increments the user count. Subsequent users coming in to perform the attach see that the user count is still 0, and reinitialize the fops, temporarily removing the patched fops. The users that are in the middle obtaining their file descriptor may then receive an invalid descriptor. The fix simply removes the user count altogether and moves the fops initialization to probe time such that it is only performed one time for the life of the adapter. In the future, if the CXL services adopt a private member for their context, that could be used to store the adapter structure reference and cxlflash could revert to a model that does not require an embedded fops. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to double the delay each timeManoj Kumar2015-10-30
| | | | | | | | | | | | | | | The operator used to double the master context response delay is incorrect and does not result in delay doubling. To fix, use a left shift instead of the XOR operator. Reported-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to prevent stale AFU RRQMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | Following an adapter reset, the AFU RRQ that resides in host memory holds stale data. This can lead to a condition where the RRQ interrupt handler tries to process stale entries and/or endlessly loops due to an out of sync generation bit. To fix, the AFU RRQ in host memory needs to be cleared after each reset. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Correct spelling, grammar, and alignment mistakesMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | There are several spelling and grammar mistakes throughout the driver. Additionally there are a handful of places where there are extra lines and unnecessary variables/statements. These are a nuisance and pollute the driver. Fix spelling and grammar issues. Update some comments for clarity and consistency. Remove extra lines and a few unneeded variables/statements. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to prevent EEH recovery failureMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | The process_sense() routine can perform a read capacity which can take some time to complete. If an EEH occurs while waiting on the read capacity, the EEH handler will wait to obtain the context's mutex in order to put the context in an error state. The EEH handler will sit and wait until the context is free, but this wait can potentially last forever (deadlock) if the scsi_execute() that performs the read capacity experiences a timeout and calls into the reset callback. When that occurs, the reset callback sees that the device is already being reset and waits for the reset to complete. This leaves two threads waiting on the other. To address this issue, make the context unavailable to new, non-system owned threads and release the context while calling into process_sense(). After returning from process_sense() the context mutex is reacquired and the context is made available again. The context can be safely moved to the error state if needed during the unavailable window as no other threads will hold its reference. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix MMIO and endianness errorsMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | Sparse uncovered several errors with MMIO operations (accessing directly) and handling endianness. These can cause issues when running in different environments. Introduce __iomem and proper endianness tags/swaps where appropriate to make driver sparse clean. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix function prolog parameters and return codesMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | Several function prologs have incorrect parameter names and return code descriptions. This can lead to confusion when reviewing the source and creates inaccurate documentation. To remedy, update the function prologs to properly reflect parameter names and return codes. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Remove unnecessary scsi_block_requestsMatthew R. Ochs2015-10-30
| | | | | | | | | | | The host reset handler is called with I/O already blocked, thus there is no need to explicitly block and unblock I/O in the handler. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Correct behavior in device reset handler following EEHMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | When the device reset handler is entered while a reset operation is taking place, the handler exits without actually sending a reset (TMF) to the targeted device. This behavior is incorrect as the device is not reset. Further complicating matters is the fact that a success is returned even when the TMF was not sent. To fix, the state is rechecked after coming out of the reset state. When the state is normal, a TMF will be sent out. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to prevent workq from accessing freed memoryMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | The workq can process work in parallel with a remove event, leading to a condition where the workq handler can access freed memory. To remedy, the workq should be terminated prior to freeing memory. Move the termination call earlier in remove and use cancel_work_sync() instead of flush_work() as there is not a need to process any scheduled work when shutting down. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Correct usage of scsi_host_put()Matthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | Currently, scsi_host_put() is being called prematurely in the remove path and is missing entirely in an error cleanup path. The former can lead to memory being freed too early with subsequent access potentially corrupting data whilst the former would result in a memory leak. Move the usage on remove to be the last cleanup action taken and introduce a call to scsi_host_put() in the one initialization error path that does not use remove to cleanup. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix AFU version access/storage and add checkMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | The AFU version is stored as a non-terminated string of bytes within a 64-bit little-endian register. Presently the value is read directly (no MMIO accessor) and is stored in a buffer that is not big enough to contain a NULL terminator. Additionally the version obtained is not evaluated against a known value to prevent usage with unsupported AFUs. All of these deficiencies can lead to a variety of problems. To remedy, use the correct MMIO accessor to read the version value into a null-terminated buffer and add a check to prevent an incompatible AFU from being used with this driver. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Remove dual port online dependencyMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | | At present, both ports must be online for the device to configure properly. Remove this dependency and the unnecessary internal LUN override logic as well. Additionally, as a refactoring measure, change the return code variable name to match that used throughout the driver. With this change, the card will be able to configure even when the link is down. At some later point when the link is transitioned to 'up', a link state change interrupt will trigger the port configuration. Note that despite its void-like behavior, the function was left with a return code for right now in case its behavior needs to be altered again in the near future based on testing. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix async interrupt bypass logicMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | A bug was introduced earlier in the development cycle when cleaning up logic statements. Instead of skipping bits that are not set, set bits are skipped, causing async interrupts to not be handled correctly. To fix, simply add back in the proper evaluation for an unset bit. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix host link up event handlingMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | Following a link up event, the LUNs available to the host may have changed. Without rescanning the host, the LUN topology is unknown to the user. In such a state, the user would be unable to locate provisioned resources. To remedy, the host should be rescanned after a link up event. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix location of setting residMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | The resid is incorrectly set which can lead to unnecessary retry attempts by the stack. This is due to resid _always_ being set using a value returned from the adapter. Instead, the value should only be interpreted and set when in an underrun scenario. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid stall while waiting on TMFMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | Borrowing the TMF waitq's spinlock causes a stall condition when waiting for the TMF to complete. To remedy, introduce our own spin lock to serialize TMF and use the appropriate wait services. Also add a timeout while waiting for a TMF completion. When a TMF times out, report back a failure such that a bigger hammer reset can occur. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid spamming the kernel logMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | During run-time the driver can be very chatty and spam the system kernel log. Various print statements can be limited and/or moved to development-only mode. Additionally, numerous prints can be converted to trace the corresponding device. Lastly, one spelling correction was made: 'entra' to 'extra'. The following changes were made: - pr_debug to pr_devel - pr_debug to pr_debug_ratelimited - pr_err to dev_err - pr_debug to dev_dbg Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Refine host/device attributesMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | Implement the following suggestions and add two new attributes to allow for debugging the port LUN table. - use scnprintf() instead of snprintf() - use DEVICE_ATTR_RO and DEVICE_ATTR_RW Suggested-by: Shane Seymour <shane.seymour@hp.com> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Make functions staticMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | Found during code inspection, that the following functions are not being used outside of the file where they are defined. Make them static. int cxlflash_send_cmd(struct afu *, struct afu_cmd *); void cxlflash_wait_resp(struct afu *, struct afu_cmd *); int cxlflash_afu_reset(struct cxlflash_cfg *); struct afu_cmd *cxlflash_cmd_checkout(struct afu *); void cxlflash_cmd_checkin(struct afu_cmd *); void init_pcr(struct cxlflash_cfg *); int init_global(struct cxlflash_cfg *); Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Correct naming of limbo state and waitqMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | Limbo is not an accurate representation of this state and is also not consistent with the terminology that other drivers use to represent this concept. Rename the state and and its associated waitq to 'reset'. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid CXL services during EEHMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | | | | | During an EEH freeze event, certain CXL services should not be called until after the hardware reset has taken place. Doing so can result in unnecessary failures and possibly cause other ill effects by triggering hardware accesses. This translates to a requirement to quiesce all threads that may potentially use CXL runtime service during this window. In particular, multiple ioctls make use of the CXL services when acting on contexts on behalf of the user. Thus, it is essential to 'drain' running ioctls _before_ proceeding with handling the EEH freeze event. Create the ability to drain ioctls by wrapping the ioctl handler call in a read semaphore and then implementing a small routine that obtains the write semaphore, effectively creating a wait point for all currently executing ioctls. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix context encode mask widthMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | The context encode mask covers more than 32-bits, making it a long integer. This should be noted by appending the ULL width suffix to the mask. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid sizeof(bool)Matthew R. Ochs2015-10-30
| | | | | | | | | | | | Using sizeof(bool) is considered poor form for various reasons and sparse warns us of that. Correct by changing type from bool to u8. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Daniel Axtens <dja@axtens.net> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix data corruption when vLUN used over multiple cardsMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | | | | If the same virtual LUN is accessed over multiple cards, only accesses made over the first card will be valid. Accesses made over the second card will go to the wrong LUN causing data corruption. This is because the global LUN's mode word was being used to determine whether the LUN table for that card needs to be programmed. The mode word would be setup by the first card, causing the LUN table for the second card to not be programmed. By unconditionally initializing the LUN table (not depending on the mode word), the problem is avoided. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix potential oops following LUN removalMatthew R. Ochs2015-10-30
| | | | | | | | | | | | | | | | | When a LUN is removed, the sdev that is associated with the LUN remains intact until its reference count drops to 0. In order to prevent an sdev from being removed while a context is still associated with it, obtain an additional reference per-context for each LUN attached to the context. This resolves a potential Oops in the release handler when a dealing with a LUN that has already been removed. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix read capacity timeoutManoj Kumar2015-10-30
| | | | | | | | | | | | | | | The timeout value for read capacity is too small. Certain devices may take longer to respond and thus the command may prematurely timeout. Additionally the literal used for the timeout is stale. Update the timeout to 30 seconds (matches the value used in sd.c) and rework the timeout literal to a more appropriate description. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Replace magic numbers with literalsManoj Kumar2015-10-30
| | | | | | | | | | | | | | | Magic numbers are not meaningful and can create confusion. As a remedy, replace them with descriptive literals. Replace 512 with literal MAX_SECTOR_UNIT. Replace 5 with literal CMD_RETRIES. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Fix to avoid invalid port_sel valueManoj Kumar2015-10-30
| | | | | | | | | | | | | | | | | | | | If two concurrent MANAGE_LUN ioctls are issued with the same WWID parameter, it would result in an incorrect value of port_sel. This is because port_sel is modified without any locks being held. If the first caller stalls after the return from find_and_create_lun(), the value of port_sel will be set incorrectly to indicate a single port, though in this case it should have been set to both ports. To fix, use the global mutex to serialize the lookup of the WWID and the subsequent modification of port_sel. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reviewed-by: Brian King <brking@linux.vnet.ibm.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
* cxlflash: Remove unused variable from queuecommandMatthew R. Ochs2015-08-26
| | | | | | | | | | | | | | | The queuecommand routine has a local dev pointer used for the dev_* prints. The two prints that currently exist are tucked under a debug define and thus can be left out. Use the actual location instead of a local to avoid this warning. This patch is intended to be applied after the "CXL Flash Error Recovery and Superpipe" series. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Reported-by: kbuild test robot <fengguang.wu@intel.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
generated by cgit v1.2.3 (git 2.25.1) at 2026-07-11 22:13:20 +0000