- 10 Nov, 2015 19 commits
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Chad Dupuis authored
Signed-off-by: Giridhar Malavali <giridhar.malavali@qlogic.com> Signed-off-by: Chad Dupuis <chad.dupuis@qlogic.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Seymour, Shane M authored
Change st driver to allow enabling or disabling debug output via sysfs file /sys/bus/scsi/drivers/st/debug_flag. Previously the only way to enable debug output was: 1. loading the driver with the module parameter debug_flag=1 2. an ioctl call (this method was also the only way to dynamically disable debug output). To use the ioctl you need a second tape drive (if you are actively testing the first tape drive) since a second process cannot open the first tape drive if it is in use. The this change is only functional if the value of the macro DEBUG in st.c is a non-zero value (which it is by default). Signed-off-by: Shane Seymour <shane.seymour@hpe.com> Reviewed-by: Laurence Oberman <oberman.l@gmail.com> Acked-by: Kai Mäkisara <kai.makisara@kolumbus.fi> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Sebastian Herbszt authored
Signed-off-by: Sebastian Herbszt <herbszt@gmx.de> Acked-by: Vasu Dev <vasu.dev@intel.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Christoph Hellwig authored
This patch changes the !blk-mq path to the same defaults as the blk-mq I/O path by always enabling block tagging, and always using host wide tags. We've had blk-mq available for a few releases so bugs with this mode should have been ironed out, and this ensures we get better coverage of over tagging setup over different configs. Signed-off-by: Christoph Hellwig <hch@lst.de> Acked-by: Jens Axboe <axboe@kernel.dk> Reviewed-by: Hannes Reinecke <hare@suse.de> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Arnd Bergmann authored
When the bnx2fc driver was changed to read the npiv table from nvram, the stack of the __bnx2fc_enable function gained an additional 1028 byte structure that gcc rightfully warns about: drivers/scsi/bnx2fc/bnx2fc_fcoe.c: In function '__bnx2fc_enable': drivers/scsi/bnx2fc/bnx2fc_fcoe.c:2134:1: warning: the frame size of 1128 bytes is larger than 1024 bytes [-Wframe-larger-than=] In order to avoid a possible kernel stack overflow and to get rid of the warning, this changes the function to use a dynamic allocation of the structure using kzalloc. Signed-off-by: Arnd Bergmann <arnd@arndb.de> Fixes: 2971ff67 ("bnx2fc: Read npiv table from nvram and create vports.") Acked-by: Chad Dupuis <chad.dupuis@qlogic.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Sudip Mukherjee authored
kmalloc() can return NULL and without checking we were dereferencing it. Moreover if kmalloc succeeds but the function fails in other parts then we were returning the error code but we missed freeing lcb_context. While at it fixed one related checkpatch warning. Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Reviewed-by: James Smart <james.smart@avagotech.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Jiri Slaby authored
There is a label pointing to the start of a while loop and a goto nested only in the loop. The goto jumps to the label in some cases. Replace the goto and the label by simple continue. Signed-off-by: Jiri Slaby <jslaby@suse.cz> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Acked-by: Vasu Dev <vasu.dev@intel.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Bart Van Assche authored
Unregister and reregister BDI devices in the proper order. This patch avoids that the following kernel warning can get triggered: WARNING: CPU: 7 PID: 203 at fs/sysfs/dir.c:31 sysfs_warn_dup+0x68/0x80() sysfs: cannot create duplicate filename '/devices/virtual/bdi/8:32' Workqueue: events_unbound async_run_entry_fn Call Trace: [<ffffffff814ff5a4>] dump_stack+0x4c/0x65 [<ffffffff810746ba>] warn_slowpath_common+0x8a/0xc0 [<ffffffff81074736>] warn_slowpath_fmt+0x46/0x50 [<ffffffff81237ca8>] sysfs_warn_dup+0x68/0x80 [<ffffffff81237d8e>] sysfs_create_dir_ns+0x7e/0x90 [<ffffffff81291f58>] kobject_add_internal+0xa8/0x320 [<ffffffff812923a0>] kobject_add+0x60/0xb0 [<ffffffff8138c937>] device_add+0x107/0x5e0 [<ffffffff8138d018>] device_create_groups_vargs+0xd8/0x100 [<ffffffff8138d05c>] device_create_vargs+0x1c/0x20 [<ffffffff8117f233>] bdi_register+0x63/0x2a0 [<ffffffff8117f497>] bdi_register_dev+0x27/0x30 [<ffffffff81281549>] add_disk+0x1a9/0x4e0 [<ffffffffa00c5739>] sd_probe_async+0x119/0x1d0 [sd_mod] [<ffffffff8109a81a>] async_run_entry_fn+0x4a/0x140 [<ffffffff81091078>] process_one_work+0x1d8/0x7c0 [<ffffffff81091774>] worker_thread+0x114/0x460 [<ffffffff81097878>] kthread+0xf8/0x110 [<ffffffff8150801f>] ret_from_fork+0x3f/0x70 See also patch "block: destroy bdi before blockdev is unregistered" (commit ID 6cd18e71). Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com> Reviewed-by: Hannes Reinecke <hare@suse.de> Cc: <stable@vger.kernel.org> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Sudip Mukherjee authored
We have been getting a warning about non ANSI function. warning: non-ANSI function declaration of function 'FPT_SccbMgrTableInitAll' Signed-off-by: Sudip Mukherjee <sudip@vectorindia.org> Acked-by: Khalid Aziz <khalid@gonehiking.org> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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K. Y. Srinivasan authored
SRB status can have additional information. Mask these out before processing SRB status. This patch was sent as part of a collection of patches more than a year ago. While the rest of the patches in the set were comitted, this patch was not. I woulod like to thank Olaf for noticing that this patch was not committed upstream. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Reviewed-by: Long Li <longli@microsoft.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Vitaly Kuznetsov authored
Storvsc driver needs to ensure there are no 'holes' in the presented sg list (all segments in the middle of the list need to be of PAGE_SIZE). When a hole is detected storvsc driver creates a 'bounce sgl' without holes and copies data over with copy_{to,from}_bounce_buffer() functions. Setting virt_boundary_mask to PAGE_SIZE - 1 guarantees we'll never see such holes so we can significantly simplify the driver. This is also supposed to bring us some performance improvement for certain workloads as we eliminate copying. Reported-by: Radim Krčmář <rkrcmar@redhat.com> Signed-off-by: Vitaly Kuznetsov <vkuznets@redhat.com> Reviewed-by: K. Y. Srinivasan <kys@microsoft.com> Tested-by: Alex Ng <alexng@microsoft.com> Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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K. Y. Srinivasan authored
Don't set the SRB_FLAGS_QUEUE_ACTION_ENABLE flag since we are not specifying tags. Without this, the qlogic driver doesn't work properly with storvsc. Signed-off-by: K. Y. Srinivasan <kys@microsoft.com> Cc: stable@vger.kernel.org Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Mahesh Rajashekhara authored
Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Mahesh Rajashekhara authored
As pci_enable_msix() deprecated, replaced with pci_enable_msix_range() Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Mahesh Rajashekhara authored
Driver blocks ioctls once it received shutdown/suspend request during suspend/hybernation. This patch unblocks ioctls on resume path. Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Mahesh Rajashekhara authored
Reset irq affinity hints before releasing IRQ. Removed duplicate code of IRQ acquire/release. Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Mahesh Rajashekhara authored
If 'IsFastPath' bit is set, then response path assumes no error and skips error check. Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Mahesh Rajashekhara authored
If writeq() not supported, then do atomic two 32bit write Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Mahesh Rajashekhara authored
This change always sets MSI interrupt mode for series-6 controller. Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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- 09 Nov, 2015 4 commits
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Mahesh Rajashekhara authored
* .suspend() and .resume() routines implemented in the driver * aac_release_resources() initiates firmware shutdown * aac_acquire_resources re-initializes the host interface Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Mahesh Rajashekhara authored
Driver sends the right size of the response buffer. Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Murthy Bhat <Murthy.Bhat@pmcs.com> Reviewed-by: Karthikeya Sunkesula <Karthikeya.Sunkesula@pmcs.com> Signed-off-by: Mahesh Rajashekhara <Mahesh.Rajashekhara@pmcs.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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John Soni Jose authored
Signed-off-by: John Soni Jose <sony.john@avagotech.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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John Soni Jose authored
While posting WRB the next_pointer of the current WRB should point to itself and the previous WRB next_pointer should point to the current WRB. The next pointer value was retrieved during alloc_pdu and was updated in wrb before ringing the doorbell. The fix retrieves the next_pointer just before ringing the doorbell and updates in the WRB. Signed-off-by: John Soni Jose <sony.john@avagotech.com> Reviewed-by: Mike Christie <michaelc@cs.wisc.edu> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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- 05 Nov, 2015 1 commit
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Christoph Hellwig authored
When dropping a lock while iterating a list we must restart the search as other threads could have manipulated the list under us. Without this we can get stuck in an endless loop. This bug was introduced by commit bc3f02a7 Author: Dan Williams <djbw@fb.com> Date: Tue Aug 28 22:12:10 2012 -0700 [SCSI] scsi_remove_target: fix softlockup regression on hot remove Which was itself trying to fix a reported soft lockup issue http://thread.gmane.org/gmane.linux.kernel/1348679 However, we believe even with this revert of the original patch, the soft lockup problem has been fixed by commit f2495e22 Author: James Bottomley <JBottomley@Parallels.com> Date: Tue Jan 21 07:01:41 2014 -0800 [SCSI] dual scan thread bug fix Thanks go to Dan Williams <dan.j.williams@intel.com> for tracking all this prior history down. Reported-by: Johannes Thumshirn <jthumshirn@suse.de> Signed-off-by: Christoph Hellwig <hch@lst.de> Tested-by: Johannes Thumshirn <jthumshirn@suse.de> Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de> Fixes: bc3f02a7 Cc: stable@vger.kernel.org Signed-off-by: James Bottomley <JBottomley@Odin.com>
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- 30 Oct, 2015 16 commits
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Manoj Kumar authored
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>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Manoj Kumar authored
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>
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Matthew R. Ochs authored
Add stanza for cxlflash SCSI 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: Andrew Donnellan <andrew.donnellan@au1.ibm.com> Signed-off-by: James Bottomley <JBottomley@Odin.com>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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Matthew R. Ochs authored
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>
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