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path: root/drivers/scsi/cxlflash
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2017-04-13scsi: cxlflash: Update sysfs helper routines to pass config structureMatthew R. Ochs
As staging for future function, pass the config pointer instead of the AFU pointer for port-related sysfs helper routines. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13scsi: cxlflash: Implement IRQ polling for RRQ processingMatthew R. Ochs
Currently, RRQ processing takes place on hardware interrupt context. This can be a heavy burden in some environments due to the overhead encountered while completing RRQ entries. In an effort to improve system performance, use the IRQ polling API to schedule this processing on softirq context. This function will be disabled by default until starting values can be established for the hardware supported by this driver. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13scsi: cxlflash: Serialize RRQ access and support offlevel processingMatthew R. Ochs
As further staging to support processing the HRRQ by other means, access to the HRRQ needs to be serialized by a disabled lock. This will allow safe access in other non-hardware interrupt contexts. In an effort to minimize the period where interrupts are disabled, support is added to queue up commands harvested from the RRQ such that they can be processed with hardware interrupts enabled. While this doesn't offer any improvement with processing on a hardware interrupt it will help when IRQ polling is supported and the command completions can execute on softirq context. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-04-13scsi: cxlflash: Separate RRQ processing from the RRQ interrupt handlerMatthew R. Ochs
In order to support processing the HRRQ by other means (e.g. polling), the processing portion of the current RRQ interrupt handler needs to be broken out into a separate routine. This will allow RRQ processing from places other than the RRQ hardware interrupt handler. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-03-03Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull more SCSI updates from James Bottomley: "This is the set of stuff that didn't quite make the initial pull and a set of fixes for stuff which did. The new stuff is basically lpfc (nvme), qedi and aacraid. The fixes cover a lot of previously submitted stuff, the most important of which probably covers some of the failing irq vectors allocation and other fallout from having the SCSI command allocated as part of the block allocation functions" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: (59 commits) scsi: qedi: Fix memory leak in tmf response processing. scsi: aacraid: remove redundant zero check on ret scsi: lpfc: use proper format string for dma_addr_t scsi: lpfc: use div_u64 for 64-bit division scsi: mac_scsi: Fix MAC_SCSI=m option when SCSI=m scsi: cciss: correct check map error. scsi: qla2xxx: fix spelling mistake: "seperator" -> "separator" scsi: aacraid: Fixed expander hotplug for SMART family scsi: mpt3sas: switch to pci_alloc_irq_vectors scsi: qedf: fixup compilation warning about atomic_t usage scsi: remove scsi_execute_req_flags scsi: merge __scsi_execute into scsi_execute scsi: simplify scsi_execute_req_flags scsi: make the sense header argument to scsi_test_unit_ready mandatory scsi: sd: improve TUR handling in sd_check_events scsi: always zero sshdr in scsi_normalize_sense scsi: scsi_dh_emc: return success in clariion_std_inquiry() scsi: fix memory leak of sdpk on when gd fails to allocate scsi: sd: make sd_devt_release() static scsi: qedf: Add QLogic FastLinQ offload FCoE driver framework. ...
2017-02-24mm, fs: reduce fault, page_mkwrite, and pfn_mkwrite to take only vmfDave Jiang
->fault(), ->page_mkwrite(), and ->pfn_mkwrite() calls do not need to take a vma and vmf parameter when the vma already resides in vmf. Remove the vma parameter to simplify things. [arnd@arndb.de: fix ARM build] Link: http://lkml.kernel.org/r/20170125223558.1451224-1-arnd@arndb.de Link: http://lkml.kernel.org/r/148521301778.19116.10840599906674778980.stgit@djiang5-desk3.ch.intel.com Signed-off-by: Dave Jiang <dave.jiang@intel.com> Signed-off-by: Arnd Bergmann <arnd@arndb.de> Reviewed-by: Ross Zwisler <ross.zwisler@linux.intel.com> Cc: Theodore Ts'o <tytso@mit.edu> Cc: Darrick J. Wong <darrick.wong@oracle.com> Cc: Matthew Wilcox <mawilcox@microsoft.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Christoph Hellwig <hch@lst.de> Cc: Jan Kara <jack@suse.com> Cc: Dan Williams <dan.j.williams@intel.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-02-23scsi: merge __scsi_execute into scsi_executeChristoph Hellwig
All but one caller want the decoded sense header, so offer the existing __scsi_execute helper as the public scsi_execute API to simply the callers. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-02-22scsi: cxlflash: Enable PCI device ID for future IBM CXL Flash AFUMatthew R. Ochs
Add support for a future IBM Coherent Accelerator (CXL) flash AFU with an ID of 0x0624. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-01-11scsi: cxlflash: Cancel scheduled workers before stopping AFUUma Krishnan
When processing an AFU asynchronous interrupt, if the action results in an operation that requires off level processing (a link reset for example), the worker thread is scheduled. In the meantime a reset event (i.e.: EEH) could unmap the AFU to recover. This results in an Oops when the worker thread tries to access the AFU mapping. [c000000f17e03b90] d000000007cd5978 cxlflash_worker_thread+0x268/0x550 [c000000f17e03c40] c00000000011883c process_one_work+0x1dc/0x680 [c000000f17e03ce0] c000000000118e80 worker_thread+0x1a0/0x520 [c000000f17e03d80] c000000000126174 kthread+0xf4/0x100 [c000000f17e03e30] c00000000000a47c ret_from_kernel_thread+0x5c/0xe0 In an effort to avoid this, a mapcount was introduced in commit b45cdbaf9f7f ("cxlflash: Resolve oops in wait_port_offline") but due to the race condition described above, this solution is incomplete. In order to fully resolve this problem and to simplify things, this commit removes the mapcount solution. Instead, the scheduled worker thread is cancelled after interrupts have been disabled and prior to the mapping being freed. Fixes: b45cdbaf9f7f ("cxlflash: Resolve oops in wait_port_offline") 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>
2017-01-11scsi: cxlflash: Cleanup printsMatthew R. Ochs
The usage of prints within the cxlflash driver is inconsistent. This hinders debug and makes the driver source and log output appear sloppy. The following cleanups help unify the prints within cxlflash: - move all prints to dev-* where possible - transition all hex prints to lowercase - standardize variable prints in debug output - derive pointers in a consistent manner - change int to bool where appropriate - remove superfluous data from prints and print statements that do not make sense Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-01-11scsi: cxlflash: Support SQ Command ModeMatthew R. Ochs
The SISLite specification outlines a new queuing model to improve over the MMIO-based IOARRIN model that exists today. This new model uses a submission queue that exists in host memory and is shared with the device. Each entry in the queue is an IOARCB that describes a transfer request. When requests are submitted, IOARCBs ('current' position tracked in host software) are populated and the submission queue tail pointer is then updated via MMIO to make the device aware of the requests. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2017-01-11scsi: cxlflash: Refactor context reset to share reset logicMatthew R. Ochs
As staging for supporting hardware with different context reset registers but a similar reset procedure, refactor the existing context reset routine to move the reset logic to a common routine. This will allow hardware with a different reset register to leverage existing code. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-11-30scsi: cxlflash: Migrate scsi command pointer to AFU commandMatthew R. Ochs
Currently, when sending a SCSI command, the pointer is stored in a reserved field of the AFU command descriptor for retrieval once the SCSI command has completed. In order to support new descriptor formats that make use of the reserved field, the pointer is migrated to outside the descriptor where it can still be found during completion processing. 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>
2016-11-30scsi: cxlflash: Migrate IOARRIN specific routines to function pointersMatthew R. Ochs
As staging for supporting hardware with a different queuing mechanism, move the send_cmd() and context_reset() routines to function pointers that are configured when the AFU is initialized. In addition, rename the existing routines to better reflect the queue model they support. 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>
2016-11-30scsi: cxlflash: Cleanup queuecommand()Matthew R. Ochs
The queuecommand routine is disorganized where it populates the private command and also contains some logic/statements that are not needed given that cxlflash devices do not (and likely never will) support scatter-gather. Restructure the code to remove the unnecessary logic and create an organized flow: handle state -> DMA map -> populate command -> send command 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>
2016-11-30scsi: cxlflash: Cleanup send_tmf()Matthew R. Ochs
The send_tmf() routine includes some copy/paste cruft that can be removed as well as the setting of an AFU command-specific while holding the tmf_slock. While not a bug, it is out of place and should be shifted down alongside the other command initialization statements for clarity. 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>
2016-11-30scsi: cxlflash: Remove AFU command lockMatthew R. Ochs
The original design of the cxlflash driver required AFU commands to convey state information across multiple threads. The IOASA "host use" byte was used to track if a command was done, errored, or timed out. A per-command spin lock was used to serialize access to this byte. As this is no longer required with the introduction of completions and various refactoring over time, the spin lock, state tracking, and associated code can be removed. To support the simplification, the wait_resp() routine is refactored to return a success or failure. Additionally, as the simplification to the AFU internal command routine, explicit assignments of AFU command fields to zero are removed as the memory is zeroed upon allocation. 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>
2016-11-30scsi: cxlflash: Wait for active AFU commands to timeout upon tear downMatthew R. Ochs
With the removal of the static private command pool, the ability to 'complete' outstanding commands was lost. While not an issue for the commands originating outside the driver, internal AFU commands are synchronous and therefore have a timeout associated with them. To avoid a stale memory access, the tear down sequence needs to ensure that there are not any active commands before proceeding. As these internal AFU commands are rare events, the simplest way to accomplish this is detecting the activity and waiting for it to timeout. 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>
2016-11-30scsi: cxlflash: Remove private command poolMatthew R. Ochs
Clean up and remove the remaining private command pool infrastructure that is no longer required. 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>
2016-11-30scsi: cxlflash: Use cmd_size for private commandsMatthew R. Ochs
Instead of using a private pool of AFU commands, use cmd_size to prime the private pool of SCSI commands such that they are allocated with a size large enough to contain an aligned AFU command. Use scsi_cmd_priv() to derive the aligned/zeroed private command on queuecommand and TMF paths. Remove cmd_checkout() as it is no longer required. The remaining AFU private command infrastructure will be removed in a cleanup commit. 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>
2016-11-30scsi: cxlflash: Allocate memory instead of using command pool for AFU syncMatthew R. Ochs
As staging for the removal of the AFU command pool, remove the reliance upon the pool for the internal AFU sync command. Instead of obtaining an AFU command from the pool, dynamically allocate memory with the appropriate alignment requirements. Since the AFU sync service is only executed from the process environment, blocking is acceptable. 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>
2016-11-30scsi: cxlflash: Remove unused buffer from AFU commandMatthew R. Ochs
The cxlflash driver originally required a per-command 4K buffer that hosted data passed to the AFU. When the routines that initiate AFU and internal SCSI commands were refactored to use scsi_execute(), the need for this buffer became obsolete. As it is no longer necessary, the buffer is removed. 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>
2016-11-30scsi: cxlflash: Avoid command room violationUma Krishnan
During test, a command room violation interrupt is occasionally seen for the master context when the CXL flash devices are stressed. After studying the code, there could be gaps in the way command room value is being cached in cxlflash. When the cached command room is zero the thread attempting to send becomes burdened with updating the cached value with the actual value from the AFU. Today, this is handled with an atomic set operation of the raw value read. Following the atomic update, the thread proceeds to send. This behavior is incorrect on two counts: - The update fails to take into account the current thread and its consumption of one of the hardware commands. - The update does not take into account other threads also atomically updating. Per design, a worker thread updates the cached value when a send thread times out. By not protecting the update with a lock, the cached value can be incorrectly clobbered. To correct these issues, the update of the cached command room has been simplified and also protected using a spin lock which is held until the MMIO is complete. This ensures the command room is properly consumed by the same thread. Update of cached value also takes into account the current thread consuming a hardware command. 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>
2016-11-30scsi: cxlflash: Improve context_reset() logicUma Krishnan
Currently, the context reset routine waits for command room to be available before sending the reset request. Per review of the SISLite specification and clarifications from the CXL Flash AFU designers, this wait is unnecessary. The reset request can be sent anytime regardless of command room, so long as only a single reset request is active at any one point in time. This commit simplifies the reset routine by removing the wait for command room. Additionally it adds a debug trace to help pinpoint hardware errors when a context reset does not complete. 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>
2016-11-30scsi: cxlflash: Fix crash in cxlflash_restore_luntable()Uma Krishnan
During test, the following crash was observed: [34538.981505] Faulting instruction address: 0xd000000007c9c870 cpu 0x9: Vector: 300 (Data Access) at [c0000007f1e8f590] pc: d000000007c9c870: cxlflash_restore_luntable+0x70/0x1d0 [cxlflash] lr: d000000007c9c84c: cxlflash_restore_luntable+0x4c/0x1d0 [cxlflash] sp: c0000007f1e8f810 msr: 9000000100009033 dar: c00000171d637438 dsisr: 40000000 current = 0xc0000007f1e43f90 paca = 0xc000000007b25100 softe: 0 irq_happened: 0x01 pid = 493, comm = eehd enter ? for help [c0000007f1e8f8a0] d000000007c940b0 init_afu+0xd60/0x1200 [cxlflash] [c0000007f1e8f9a0] d000000007c945a8 cxlflash_pci_slot_reset+0x58/0xe0 [cxlflash] [c0000007f1e8fa20] d00000000715f790 cxl_pci_slot_reset+0x230/0x340 [cxl] [c0000007f1e8fae0] c000000000040dd4 eeh_report_reset+0x144/0x180 [c0000007f1e8fb20] c00000000003f708 eeh_pe_dev_traverse+0x98/0x170 [c0000007f1e8fbb0] c000000000041618 eeh_handle_normal_event+0x328/0x410 [c0000007f1e8fc30] c000000000041db8 eeh_handle_event+0x178/0x330 [c0000007f1e8fce0] c000000000042118 eeh_event_handler+0x1a8/0x1b0 [c0000007f1e8fd80] c00000000011420c kthread+0xec/0x100 [c0000007f1e8fe30] c00000000000a47c ret_from_kernel_thread+0x5c/0xe0 When superpipe mode is disabled for a LUN, the references for the local lun are deleted but the LUN is still identified as being present in the LUN table. This mismatched state can result in the above crash when the LUN table is restored during an error recovery operation. To fix this issue, the local LUN information structure is updated to reflect the LUN is no longer in the LUN table once all references to the LUN are gone. 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>
2016-11-30scsi: cxlflash: Set sg_tablesize to 1 instead of SG_NONEUma Krishnan
The following Oops is encountered when blk_mq is enabled with the cxlflash driver: [ 2960.817172] Oops: Kernel access of bad area, sig: 11 [#5] [ 2960.817309] NIP __blk_mq_run_hw_queue+0x278/0x4c0 [ 2960.817313] LR __blk_mq_run_hw_queue+0x2bc/0x4c0 [ 2960.817314] Call Trace: [ 2960.817320] __blk_mq_run_hw_queue+0x2bc/0x4c0 (unreliable) [ 2960.817324] blk_mq_run_hw_queue+0xd8/0x100 [ 2960.817329] blk_mq_insert_requests+0x14c/0x1f0 [ 2960.817333] blk_mq_flush_plug_list+0x150/0x190 [ 2960.817338] blk_flush_plug_list+0x11c/0x2b0 [ 2960.817344] blk_finish_plug+0x58/0x80 [ 2960.817348] __do_page_cache_readahead+0x1c0/0x2e0 [ 2960.817352] force_page_cache_readahead+0x68/0xd0 [ 2960.817356] generic_file_read_iter+0x43c/0x6a0 [ 2960.817359] blkdev_read_iter+0x68/0xa0 [ 2960.817361] __vfs_read+0x11c/0x180 [ 2960.817364] vfs_read+0xa4/0x1c0 [ 2960.817366] SyS_read+0x6c/0x110 [ 2960.817369] system_call+0x38/0xb4 The SCSI blk_mq stack assumes that sg_tablesize is always a non-zero value with scsi_mq_setup_tags() allocating tags using sg_tablesize. The cxlflash driver currently uses SG_NONE (0) for the sg_tablesize as the devices it supports are not capable of scatter gather. This mismatch of values results in the Oops above. To resolve this issue, sg_tablesize for cxlflash can simply be set to 1, a value which satisfies the constraints in cxlflash and the lack of support of SG_NONE in SCSI blk_mq. 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>
2016-09-14scsi: cxlflash: Fix context reference tracking on detachMatthew R. Ochs
Commit 888baf069f49 ("scsi: cxlflash: Add kref to context") introduced a kref to the context. In particular, the detach routine was updated to use the kref services for managing the removal and destruction of a context. As part of this change, the tracking mechanism internal to the detach handler was refactored. This introduced a bug that can cause the tracking state to be lost. This can lead to a situation where exclusive access to a context is prematurely [and unknowingly] relinquished for the executing thread. To remedy, only update the tracking state when the kref operation indicates the context was removed. Fixes: 888baf069f49 ("scsi: cxlflash: Add kref to context") 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>
2016-09-14scsi: cxlflash: Refactor WWPN setupMatthew R. Ochs
Commit 964497b3bf3f ("cxlflash: Remove dual port online dependency") logically removed the ability for the WWPN setup routine afu_set_wwpn() to return a non-success value. This routine can safely be made a void to simplify the code as there is no longer a need to report a failure. 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>
2016-09-14scsi: cxlflash: Improve EEH recovery timeMatthew R. Ochs
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>
2016-09-14scsi: cxlflash: Fix to avoid EEH and host reset collisionsMatthew R. Ochs
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>
2016-09-09scsi: cxlflash: Remove the device cleanly in the system shutdown pathUma Krishnan
Commit 704c4b0ddc03 ("cxlflash: Shutdown notify support for CXL Flash cards") was recently introduced to notify the AFU when a system is going down. Due to the position of the cxlflash driver in the device stack, cxlflash devices are _always_ removed during a reboot/shutdown. This can lead to a crash if the cxlflash shutdown hook is invoked _after_ the shutdown hook for the owning virtual PHB. Furthermore, the current implementation of shutdown/remove hooks for cxlflash are not tolerant to being invoked when the device is not enabled. This can also lead to a crash in situations where the remove hook is invoked after the device has been removed via the vPHBs shutdown hook. An example of this scenario would be an EEH reset failure while a reboot/shutdown is in progress. To solve both problems, the shutdown hook for cxlflash is updated to simply remove the device. This path already includes the AFU notification and thus this solution will continue to perform the original intent. At the same time, the remove hook is updated to protect against being called when the device is not enabled. Fixes: 704c4b0ddc03 ("cxlflash: Shutdown notify support for CXL Flash cards") 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>
2016-09-09scsi: cxlflash: Scan host only after the port is ready for I/OUma Krishnan
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>
2016-08-23scsi: cxlflash: Remove adapter file descriptor cacheMatthew R. Ochs
The adapter file descriptor was previously cached within the kernel for a given context in order to support performing a close on behalf of an application. This is no longer needed as applications are now required to perform a close on the adapter file descriptor. Inspired-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-23scsi: cxlflash: Transition to application close modelMatthew R. Ochs
Caching the adapter file descriptor and performing a close on behalf of an application is a poor design. This is due to the fact that once a file descriptor in installed, it is free to be altered without the knowledge of the cxlflash driver. This can lead to inconsistencies between the application and kernel. Furthermore, the nature of the former design is more exploitable and thus should be abandoned. To support applications performing a close on the adapter file that is associated with a context, a new flag is introduced to the user API to indicate to applications that they are responsible for the close following the cleanup (detach) of a context. The documentation is also updated to reflect this change in behavior. Inspired-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-18scsi: cxlflash: Add kref to contextMatthew R. Ochs
Currently, context user references are tracked via the list of LUNs that have attached to the context. While convenient, this is not intuitive without a deep study of the code and is inconsistent with the existing reference tracking patterns within the kernel. This design choice can lead to future bug injection. To improve code comprehension and better protect against future bugs, add explicit reference counting to contexts and migrate the context removal code to the kref release handler. Inspired-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-18scsi: cxlflash: Cache owning adapter within contextMatthew R. Ochs
The context removal routine requires access to the owning adapter structure to reset the context within the AFU as part of the tear down sequence. In order to support kref adoption, the owning adapter must be accessible from the release handler. As the kref framework only provides the kref reference as the sole parameter, another means is needed to derive the owning adapter. As a remedy, the owning adapter reference is saved off within the context during initialization. Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-18scsi: cxlflash: Avoid mutex when destroying contextMatthew R. Ochs
Context information structures are protected by a mutex that is held when accessing/manipulating the context. When the code that manages these structures was authored, a decision was made to include taking the mutex as part of the allocation/initialization sequence and also handle the scenario where the mutex was already held when freeing the context. While not a problem outright, this design decision has been deemed as too flexible and the code should be made more rigid to avoid future bugs. In addition, further review of the code yields that the existing mutex manipulations in both of these context management paths are superfluous. This commit removes the obtaining of the context mutex in the context initialization routine and assumes the mutex is not held in the context free path. Inspired-by: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-08-05Merge tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsiLinus Torvalds
Pull SCSI fixes from James Bottomley: "This is seven basic fixes (plus one MAINTAINER update) which came in close to the merge window" * tag 'scsi-misc' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi: ipr: Fix error return code in ipr_probe_ioa() fcoe: add missing destroy_workqueue() on error in fcoe_init() lpfc: Fix possible NULL pointer dereference fcoe: Use default VLAN for FIP VLAN discovery ipr: Wait to do async scan until scsi host is initialized MAINTAINERS: Update cxlflash maintainers cxlflash: Verify problem state area is mapped before notifying shutdown lpfc: fix oops in lpfc_sli4_scmd_to_wqidx_distr() from lpfc_send_taskmgmt()
2016-07-30Merge tag 'powerpc-4.8-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "Highlights: - PowerNV PCI hotplug support. - Lots more Power9 support. - eBPF JIT support on ppc64le. - Lots of cxl updates. - Boot code consolidation. Bug fixes: - Fix spin_unlock_wait() from Boqun Feng - Fix stack pointer corruption in __tm_recheckpoint() from Michael Neuling - Fix multiple bugs in memory_hotplug_max() from Bharata B Rao - mm: Ensure "special" zones are empty from Oliver O'Halloran - ftrace: Separate the heuristics for checking call sites from Michael Ellerman - modules: Never restore r2 for a mprofile-kernel style mcount() call from Michael Ellerman - Fix endianness when reading TCEs from Alexey Kardashevskiy - start rtasd before PCI probing from Greg Kurz - PCI: rpaphp: Fix slot registration for multiple slots under a PHB from Tyrel Datwyler - powerpc/mm: Add memory barrier in __hugepte_alloc() from Sukadev Bhattiprolu Cleanups & fixes: - Drop support for MPIC in pseries from Rashmica Gupta - Define and use PPC64_ELF_ABI_v2/v1 from Michael Ellerman - Remove unused symbols in asm-offsets.c from Rashmica Gupta - Fix SRIOV not building without EEH enabled from Russell Currey - Remove kretprobe_trampoline_holder from Thiago Jung Bauermann - Reduce log level of PCI I/O space warning from Benjamin Herrenschmidt - Add array bounds checking to crash_shutdown_handlers from Suraj Jitindar Singh - Avoid -maltivec when using clang integrated assembler from Anton Blanchard - Fix array overrun in ppc_rtas() syscall from Andrew Donnellan - Fix error return value in cmm_mem_going_offline() from Rasmus Villemoes - export cpu_to_core_id() from Mauricio Faria de Oliveira - Remove old symbols from defconfigs from Andrew Donnellan - Update obsolete comments in setup_32.c about entry conditions from Benjamin Herrenschmidt - Add comment explaining the purpose of setup_kdump_trampoline() from Benjamin Herrenschmidt - Merge the RELOCATABLE config entries for ppc32 and ppc64 from Kevin Hao - Remove RELOCATABLE_PPC32 from Kevin Hao - Fix .long's in tlb-radix.c to more meaningful from Balbir Singh Minor cleanups & fixes: - Andrew Donnellan, Anna-Maria Gleixner, Anton Blanchard, Benjamin Herrenschmidt, Bharata B Rao, Christophe Leroy, Colin Ian King, Geliang Tang, Greg Kurz, Madhavan Srinivasan, Michael Ellerman, Michael Ellerman, Stephen Rothwell, Stewart Smith. Freescale updates from Scott: - "Highlights include more 8xx optimizations, device tree updates, and MVME7100 support." PowerNV PCI hotplug from Gavin Shan: - PCI: Add pcibios_setup_bridge() - Override pcibios_setup_bridge() - Remove PCI_RESET_DELAY_US - Move pnv_pci_ioda_setup_opal_tce_kill() around - Increase PE# capacity - Allocate PE# in reverse order - Create PEs in pcibios_setup_bridge() - Setup PE for root bus - Extend PCI bridge resources - Make pnv_ioda_deconfigure_pe() visible - Dynamically release PE - Update bridge windows on PCI plug - Delay populating pdn - Support PCI slot ID - Use PCI slot reset infrastructure - Introduce pnv_pci_get_slot_id() - Functions to get/set PCI slot state - PCI/hotplug: PowerPC PowerNV PCI hotplug driver - Print correct PHB type names Power9 idle support from Shreyas B. Prabhu: - set power_save func after the idle states are initialized - Use PNV_THREAD_WINKLE macro while requesting for winkle - make hypervisor state restore a function - Rename idle_power7.S to idle_book3s.S - Rename reusable idle functions to hardware agnostic names - Make pnv_powersave_common more generic - abstraction for saving SPRs before entering deep idle states - Add platform support for stop instruction - cpuidle/powernv: Use CPUIDLE_STATE_MAX instead of MAX_POWERNV_IDLE_STATES - cpuidle/powernv: cleanup cpuidle-powernv.c - cpuidle/powernv: Add support for POWER ISA v3 idle states - Use deepest stop state when cpu is offlined Power9 PMU from Madhavan Srinivasan: - factor out power8 pmu macros and defines - factor out power8 pmu functions - factor out power8 __init_pmu code - Add power9 event list macros for generic and cache events - Power9 PMU support - Export Power9 generic and cache events to sysfs Power9 preliminary interrupt & PCI support from Benjamin Herrenschmidt: - Add XICS emulation APIs - Move a few exception common handlers to make room - Add support for HV virtualization interrupts - Add mechanism to force a replay of interrupts - Add ICP OPAL backend - Discover IODA3 PHBs - pci: Remove obsolete SW invalidate - opal: Add real mode call wrappers - Rename TCE invalidation calls - Remove SWINV constants and obsolete TCE code - Rework accessing the TCE invalidate register - Fallback to OPAL for TCE invalidations - Use the device-tree to get available range of M64's - Check status of a PHB before using it - pci: Don't try to allocate resources that will be reassigned Other Power9: - Send SIGBUS on unaligned copy and paste from Chris Smart - Large Decrementer support from Oliver O'Halloran - Load Monitor Register Support from Jack Miller Performance improvements from Anton Blanchard: - Avoid load hit store in __giveup_fpu() and __giveup_altivec() - Avoid load hit store in setup_sigcontext() - Remove assembly versions of strcpy, strcat, strlen and strcmp - Align hot loops of some string functions eBPF JIT from Naveen N. Rao: - Fix/enhance 32-bit Load Immediate implementation - Optimize 64-bit Immediate loads - Introduce rotate immediate instructions - A few cleanups - Isolate classic BPF JIT specifics into a separate header - Implement JIT compiler for extended BPF Operator Panel driver from Suraj Jitindar Singh: - devicetree/bindings: Add binding for operator panel on FSP machines - Add inline function to get rc from an ASYNC_COMP opal_msg - Add driver for operator panel on FSP machines Sparse fixes from Daniel Axtens: - make some things static - Introduce asm-prototypes.h - Include headers containing prototypes - Use #ifdef __BIG_ENDIAN__ #else for REG_BYTE - kvm: Clarify __user annotations - Pass endianness to sparse - Make ppc_md.{halt, restart} __noreturn MM fixes & cleanups from Aneesh Kumar K.V: - radix: Update LPCR HR bit as per ISA - use _raw variant of page table accessors - Compile out radix related functions if RADIX_MMU is disabled - Clear top 16 bits of va only on older cpus - Print formation regarding the the MMU mode - hash: Update SDR1 size encoding as documented in ISA 3.0 - radix: Update PID switch sequence - radix: Update machine call back to support new HCALL. - radix: Add LPID based tlb flush helpers - radix: Add a kernel command line to disable radix - Cleanup LPCR defines Boot code consolidation from Benjamin Herrenschmidt: - Move epapr_paravirt_early_init() to early_init_devtree() - cell: Don't use flat device-tree after boot - ge_imp3a: Don't use the flat device-tree after boot - mpc85xx_ds: Don't use the flat device-tree after boot - mpc85xx_rdb: Don't use the flat device-tree after boot - Don't test for machine type in rtas_initialize() - Don't test for machine type in smp_setup_cpu_maps() - dt: Add of_device_compatible_match() - Factor do_feature_fixup calls - Move 64-bit feature fixup earlier - Move 64-bit memory reserves to setup_arch() - Use a cachable DART - Move FW feature probing out of pseries probe() - Put exception configuration in a common place - Remove early allocation of the SMU command buffer - Move MMU backend selection out of platform code - pasemi: Remove IOBMAP allocation from platform probe() - mm/hash: Don't use machine_is() early during boot - Don't test for machine type to detect HEA special case - pmac: Remove spurrious machine type test - Move hash table ops to a separate structure - Ensure that ppc_md is empty before probing for machine type - Move 64-bit probe_machine() to later in the boot process - Move 32-bit probe() machine to later in the boot process - Get rid of ppc_md.init_early() - Move the boot time info banner to a separate function - Move setting of {i,d}cache_bsize to initialize_cache_info() - Move the content of setup_system() to setup_arch() - Move cache info inits to a separate function - Re-order the call to smp_setup_cpu_maps() - Re-order setup_panic() - Make a few boot functions __init - Merge 32-bit and 64-bit setup_arch() Other new features: - tty/hvc: Use IRQF_SHARED for OPAL hvc consoles from Sam Mendoza-Jonas - tty/hvc: Use opal irqchip interface if available from Sam Mendoza-Jonas - powerpc: Add module autoloading based on CPU features from Alastair D'Silva - crypto: vmx - Convert to CPU feature based module autoloading from Alastair D'Silva - Wake up kopald polling thread before waiting for events from Benjamin Herrenschmidt - xmon: Dump ISA 2.06 SPRs from Michael Ellerman - xmon: Dump ISA 2.07 SPRs from Michael Ellerman - Add a parameter to disable 1TB segs from Oliver O'Halloran - powerpc/boot: Add OPAL console to epapr wrappers from Oliver O'Halloran - Assign fixed PHB number based on device-tree properties from Guilherme G. Piccoli - pseries: Add pseries hotplug workqueue from John Allen - pseries: Add support for hotplug interrupt source from John Allen - pseries: Use kernel hotplug queue for PowerVM hotplug events from John Allen - pseries: Move property cloning into its own routine from Nathan Fontenot - pseries: Dynamic add entires to associativity lookup array from Nathan Fontenot - pseries: Auto-online hotplugged memory from Nathan Fontenot - pseries: Remove call to memblock_add() from Nathan Fontenot cxl: - Add set and get private data to context struct from Michael Neuling - make base more explicitly non-modular from Paul Gortmaker - Use for_each_compatible_node() macro from Wei Yongjun - Frederic Barrat - Abstract the differences between the PSL and XSL - Make vPHB device node match adapter's - Philippe Bergheaud - Add mechanism for delivering AFU driver specific events - Ignore CAPI adapters misplaced in switched slots - Refine slice error debug messages - Andrew Donnellan - static-ify variables to fix sparse warnings - PCI/hotplug: pnv_php: export symbols and move struct types needed by cxl - PCI/hotplug: pnv_php: handle OPAL_PCI_SLOT_OFFLINE power state - Add cxl_check_and_switch_mode() API to switch bi-modal cards - remove dead Kconfig options - fix potential NULL dereference in free_adapter() - Ian Munsie - Update process element after allocating interrupts - Add support for CAPP DMA mode - Fix allowing bogus AFU descriptors with 0 maximum processes - Fix allocating a minimum of 2 pages for the SPA - Fix bug where AFU disable operation had no effect - Workaround XSL bug that does not clear the RA bit after a reset - Fix NULL pointer dereference on kernel contexts with no AFU interrupts - powerpc/powernv: Split cxl code out into a separate file - Add cxl_slot_is_supported API - Enable bus mastering for devices using CAPP DMA mode - Move cxl_afu_get / cxl_afu_put to base - Allow a default context to be associated with an external pci_dev - Do not create vPHB if there are no AFU configuration records - powerpc/powernv: Add support for the cxl kernel api on the real phb - Add support for using the kernel API with a real PHB - Add kernel APIs to get & set the max irqs per context - Add preliminary workaround for CX4 interrupt limitation - Add support for interrupts on the Mellanox CX4 - Workaround PE=0 hardware limitation in Mellanox CX4 - powerpc/powernv: Fix pci-cxl.c build when CONFIG_MODULES=n selftests: - Test unaligned copy and paste from Chris Smart - Load Monitor Register Tests from Jack Miller - Cyril Bur - exec() with suspended transaction - Use signed long to read perf_event_paranoid - Fix usage message in context_switch - Fix generation of vector instructions/types in context_switch - Michael Ellerman - Use "Delta" rather than "Error" in normal output - Import Anton's mmap & futex micro benchmarks - Add a test for PROT_SAO" * tag 'powerpc-4.8-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (263 commits) powerpc/mm: Parenthesise IS_ENABLED() in if condition tty/hvc: Use opal irqchip interface if available tty/hvc: Use IRQF_SHARED for OPAL hvc consoles selftests/powerpc: exec() with suspended transaction powerpc: Improve comment explaining why we modify VRSAVE powerpc/mm: Drop unused externs for hpte_init_beat[_v3]() powerpc/mm: Rename hpte_init_lpar() and move the fallback to a header powerpc/mm: Fix build break when PPC_NATIVE=n crypto: vmx - Convert to CPU feature based module autoloading powerpc: Add module autoloading based on CPU features powerpc/powernv/ioda: Fix endianness when reading TCEs powerpc/mm: Add memory barrier in __hugepte_alloc() powerpc/modules: Never restore r2 for a mprofile-kernel style mcount() call powerpc/ftrace: Separate the heuristics for checking call sites powerpc: Merge 32-bit and 64-bit setup_arch() powerpc/64: Make a few boot functions __init powerpc: Re-order setup_panic() powerpc: Re-order the call to smp_setup_cpu_maps() powerpc/32: Move cache info inits to a separate function powerpc/64: Move the content of setup_system() to setup_arch() ...
2016-07-27cxlflash: Verify problem state area is mapped before notifying shutdownUma Krishnan
If an EEH or some other hard error occurs while the adapter instance was being initialized, on the subsequent shutdown of the device, the system could crash with: [c000000f1da03b60] c0000000005eccfc pci_device_shutdown+0x6c/0x100 [c000000f1da03ba0] c0000000006d67d4 device_shutdown+0x1b4/0x2c0 [c000000f1da03c40] c0000000000ea30c kernel_restart_prepare+0x5c/0x80 [c000000f1da03c70] c0000000000ea48c kernel_restart+0x2c/0xc0 [c000000f1da03ce0] c0000000000ea970 SyS_reboot+0x1c0/0x2d0 [c000000f1da03e30] c000000000009204 system_call+0x38/0xb4 This crash is due to the AFU not being mapped when the shutdown notification routine is called and is a regression that was inserted recently with Commit 704c4b0ddc03 ("cxlflash: Shutdown notify support for CXL Flash cards"). As a fix, shutdown notification should only occur when the AFU is mapped. Fixes: 704c4b0ddc03 ("cxlflash: Shutdown notify support for CXL Flash cards") Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Reviewed-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-07-19cxl: remove dead Kconfig optionsAndrew Donnellan
Remove the CXL_KERNEL_API and CXL_EEH Kconfig options, as they were only needed to coordinate the merging of the cxlflash driver. Also remove the stub implementation of cxl_perst_reloads_same_image() in cxlflash which is only used if CXL_EEH isn't defined (i.e. never). Suggested-by: Ian Munsie <imunsie@au1.ibm.com> Signed-off-by: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Acked-by: Ian Munsie <imunsie@au1.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
2016-07-12cxlflash: Shutdown notify support for CXL Flash cardsUma Krishnan
Some CXL Flash cards need notification of device shutdown in order to flush pending I/Os. A PCI notification hook for shutdown has been added where the driver notifies the card and returns. When the device is removed in the PCI remove path, notification code will wait for shutdown processing to complete. Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-07-12cxlflash: Add device dependent flagsUma Krishnan
Device dependent flags are needed to support functions that are specific to a particular device. One such case is - some CXL Flash cards need to be notified of device shutdown. For other CXL devices, this feature does not prove to be useful yet. Such distinct features need to be identified in the driver to bypass or invoke specific functionality. In this patch, a member 'flags' has been added to device dependent values. These flags will be used and expanded in the future to support various device specific functions. Signed-off-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-07-12cxlflash: Fix to drain operations from previous resetManoj N. Kumar
While running 'sg_reset -H' in a loop with a user-space application active, hit the following exception: cpu 0x2: Vector: 300 (Data Access) pc: : afu_attach+0x50/0x240 [cxlflash] lr: : cxlflash_afu_recover+0x3dc/0x7d0 [cxlflash] pid = 20365, comm = run_block_fvt Linux version 4.5.0-491-26f710d+ cxlflash_afu_recover+0x3dc/0x7d0 [cxlflash] cxlflash_ioctl+0x5a8/0x6f0 [cxlflash] scsi_ioctl+0x3b0/0x4c0 sd_ioctl+0x110/0x190 blkdev_ioctl+0x28c/0xc20 block_ioctl+0xa4/0xd0 do_vfs_ioctl+0xd8/0x8c0 SyS_ioctl+0xd4/0xf0 system_call+0x38/0xb4 The problem here is that the problem space area is unmapped while the application issues the DK_CXLFLASH_RECOVER_AFU ioctl. This is the order I observe: proc1 proc2 1) sg_reset 2) ioctl(DK_CXLFLASH_RECOVER_AFU) 3) sg_reset again causing a PSA unmap 4) continues RECOVER_AFU processing The resolution to this problem is to have the reset handler drain all outstanding user space initiated ioctls before proceeding. It is safe to drain after the state has been changed to STATE_RESET. Also since drain_ioctls() was static, it had to be moved up a bit to be before cxlflash_eh_host_reset_handler(). Signed-off-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
2016-05-05cxlflash: Fix to resolve dead-lock during EEH recoveryManoj N. Kumar
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>
2016-04-05Merge branch 'fixes-base' into fixesJames Bottomley
2016-03-28cxlflash: Move to exponential back-off when cmd_room is not availableManoj N. Kumar
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>
2016-03-28cxlflash: Fix regression issue with re-ordering patchManoj N. Kumar
While running 'sg_reset -H' back to back the following exception was seen: [ 735.115695] Faulting instruction address: 0xd0000000098c0864 cpu 0x0: Vector: 300 (Data Access) at [c000000ffffafa80] pc: d0000000098c0864: cxlflash_async_err_irq+0x84/0x5c0 [cxlflash] lr: c00000000013aed0: handle_irq_event_percpu+0xa0/0x310 sp: c000000ffffafd00 msr: 9000000000009033 dar: 2010000 dsisr: 40000000 current = 0xc000000001510880 paca = 0xc00000000fb80000 softe: 0 irq_happened: 0x01 pid = 0, comm = swapper/0 Linux version 4.5.0-491-26f710d+ enter ? for help [c000000ffffafe10] c00000000013aed0 handle_irq_event_percpu+0xa0/0x310 [c000000ffffafed0] c00000000013b1a8 handle_irq_event+0x68/0xc0 [c000000ffffaff00] c0000000001404ec handle_fasteoi_irq+0xec/0x2a0 [c000000ffffaff30] c00000000013a084 generic_handle_irq+0x54/0x80 [c000000ffffaff60] c000000000011130 __do_irq+0x80/0x1d0 [c000000ffffaff90] c000000000024d40 call_do_irq+0x14/0x24 [c000000001573a20] c000000000011318 do_IRQ+0x98/0x140 [c000000001573a70] c000000000002594 hardware_interrupt_common+0x114/0x180 This exception is being hit because the async_err interrupt path performs an MMIO to read the interrupt status register. The MMIO region in this case is not available. Commit 6ded8b3cbd9a ("cxlflash: Unmap problem state area before detaching master context") re-ordered the sequence in which term_mc() and stop_afu() are called. This introduces a window for interrupts to come in with the problem space area unmapped, that did not exist previously. The fix is to separate the disabling of all AFU interrupts to a distinct function, term_intr() so that it is the first thing that is done in the tear down process. To keep the initialization process symmetric, separate the AFU interrupt setup also to a distinct function: init_intr(). Fixes: 6ded8b3cbd9a ("cxlflash: Unmap problem state area before detaching master context") 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>
2016-03-19Merge tag 'powerpc-4.6-1' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux Pull powerpc updates from Michael Ellerman: "This was delayed a day or two by some build-breakage on old toolchains which we've now fixed. There's two PCI commits both acked by Bjorn. There's one commit to mm/hugepage.c which is (co)authored by Kirill. Highlights: - Restructure Linux PTE on Book3S/64 to Radix format from Paul Mackerras - Book3s 64 MMU cleanup in preparation for Radix MMU from Aneesh Kumar K.V - Add POWER9 cputable entry from Michael Neuling - FPU/Altivec/VSX save/restore optimisations from Cyril Bur - Add support for new ftrace ABI on ppc64le from Torsten Duwe Various cleanups & minor fixes from: - Adam Buchbinder, Andrew Donnellan, Balbir Singh, Christophe Leroy, Cyril Bur, Luis Henriques, Madhavan Srinivasan, Pan Xinhui, Russell Currey, Sukadev Bhattiprolu, Suraj Jitindar Singh. General: - atomics: Allow architectures to define their own __atomic_op_* helpers from Boqun Feng - Implement atomic{, 64}_*_return_* variants and acquire/release/ relaxed variants for (cmp)xchg from Boqun Feng - Add powernv_defconfig from Jeremy Kerr - Fix BUG_ON() reporting in real mode from Balbir Singh - Add xmon command to dump OPAL msglog from Andrew Donnellan - Add xmon command to dump process/task similar to ps(1) from Douglas Miller - Clean up memory hotplug failure paths from David Gibson pci/eeh: - Redesign SR-IOV on PowerNV to give absolute isolation between VFs from Wei Yang. - EEH Support for SRIOV VFs from Wei Yang and Gavin Shan. - PCI/IOV: Rename and export virtfn_{add, remove} from Wei Yang - PCI: Add pcibios_bus_add_device() weak function from Wei Yang - MAINTAINERS: Update EEH details and maintainership from Russell Currey cxl: - Support added to the CXL driver for running on both bare-metal and hypervisor systems, from Christophe Lombard and Frederic Barrat. - Ignore probes for virtual afu pci devices from Vaibhav Jain perf: - Export Power8 generic and cache events to sysfs from Sukadev Bhattiprolu - hv-24x7: Fix usage with chip events, display change in counter values, display domain indices in sysfs, eliminate domain suffix in event names, from Sukadev Bhattiprolu Freescale: - Updates from Scott: "Highlights include 8xx optimizations, 32-bit checksum optimizations, 86xx consolidation, e5500/e6500 cpu hotplug, more fman and other dt bits, and minor fixes/cleanup" * tag 'powerpc-4.6-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (179 commits) powerpc: Fix unrecoverable SLB miss during restore_math() powerpc/8xx: Fix do_mtspr_cpu6() build on older compilers powerpc/rcpm: Fix build break when SMP=n powerpc/book3e-64: Use hardcoded mttmr opcode powerpc/fsl/dts: Add "jedec,spi-nor" flash compatible powerpc/T104xRDB: add tdm riser card node to device tree powerpc32: PAGE_EXEC required for inittext powerpc/mpc85xx: Add pcsphy nodes to FManV3 device tree powerpc/mpc85xx: Add MDIO bus muxing support to the board device tree(s) powerpc/86xx: Introduce and use common dtsi powerpc/86xx: Update device tree powerpc/86xx: Move dts files to fsl directory powerpc/86xx: Switch to kconfig fragments approach powerpc/86xx: Update defconfigs powerpc/86xx: Consolidate common platform code powerpc32: Remove one insn in mulhdu powerpc32: small optimisation in flush_icache_range() powerpc: Simplify test in __dma_sync() powerpc32: move xxxxx_dcache_range() functions inline powerpc32: Remove clear_pages() and define clear_page() inline ...
2016-03-09cxlflash: Use new cxl_pci_read_adapter_vpd() APIFrederic Barrat
To read the adapter VPD, drivers can't rely on pci config APIs, as it wouldn't work on powerVM. cxl introduced a new kernel API especially for this, so start using it. Co-authored-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Signed-off-by: Frederic Barrat <fbarrat@linux.vnet.ibm.com> Signed-off-by: Christophe Lombard <clombard@linux.vnet.ibm.com> Reviewed-by: Uma Krishnan <ukrishn@linux.vnet.ibm.com> Acked-by: Matthew R. Ochs <mrochs@linux.vnet.ibm.com> Acked-by: Manoj N. Kumar <manoj@linux.vnet.ibm.com> Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>