kernel.git/drivers/nvme/target/fcloop.c, branch linux-4.19.y

nvme-fc: Revert "add module to ops template to allow module references"

2020-04-17T08:48:45Z

commit 8c5c660529209a0e324c1c1a35ce3f83d67a2aa5 upstream. The original patch was to resolve the lldd being able to be unloaded while being used to talk to the boot device of the system. However, the end result of the original patch is that any driver unload while a nvme controller is live via the lldd is now being prohibited. Given the module reference, the module teardown routine can't be called, thus there's no way, other than manual actions to terminate the controllers. Fixes: 863fbae929c7 ("nvme_fc: add module to ops template to allow module references") Cc: # v5.4+ Signed-off-by: James Smart Reviewed-by: Himanshu Madhani Signed-off-by: Christoph Hellwig Signed-off-by: Greg Kroah-Hartman

nvme_fc: add module to ops template to allow module references

2020-01-09T09:18:54Z

[ Upstream commit 863fbae929c7a5b64e96b8a3ffb34a29eefb9f8f ] In nvme-fc: it's possible to have connected active controllers and as no references are taken on the LLDD, the LLDD can be unloaded. The controller would enter a reconnect state and as long as the LLDD resumed within the reconnect timeout, the controller would resume. But if a namespace on the controller is the root device, allowing the driver to unload can be problematic. To reload the driver, it may require new io to the boot device, and as it's no longer connected we get into a catch-22 that eventually fails, and the system locks up. Fix this issue by taking a module reference for every connected controller (which is what the core layer did to the transport module). Reference is cleared when the controller is removed. Acked-by: Himanshu Madhani Reviewed-by: Christoph Hellwig Signed-off-by: James Smart Signed-off-by: Keith Busch Signed-off-by: Sasha Levin

nvmet-fcloop: suppress a compiler warning

2019-12-01T08:16:29Z

[ Upstream commit 1216e9ef18b84f4fb5934792368fb01eb3540520 ] Building with W=1 enables the compiler warning -Wimplicit-fallthrough=3. That option does not recognize the fall-through comment in the fcloop driver. Add a fall-through comment that is recognized for -Wimplicit-fallthrough=3. This patch avoids that the compiler reports the following warning when building with W=1: drivers/nvme/target/fcloop.c:647:6: warning: this statement may fall through [-Wimplicit-fallthrough=] if (op == NVMET_FCOP_READDATA) ^ Signed-off-by: Bart Van Assche Reviewed-by: James Smart Signed-off-by: Christoph Hellwig Signed-off-by: Sasha Levin

nvme-fcloop: Fix dropped LS's to removed target port

2018-08-28T06:40:43Z

When a targetport is removed from the config, fcloop will avoid calling the LS done() routine thinking the targetport is gone. This leaves the initiator reset/reconnect hanging as it waits for a status on the Create_Association LS for the reconnect. Change the filter in the LS callback path. If tport null (set when failed validation before "sending to remote port"), be sure to call done. This was the main bug. But, continue the logic that only calls done if tport was set but there is no remoteport (e.g. case where remoteport has been removed, thus host doesn't expect a completion). Signed-off-by: James Smart Signed-off-by: Christoph Hellwig

Merge branch 'for-4.16/block' of git://git.kernel.dk/linux-block

2018-01-29T19:51:49Z

Pull block updates from Jens Axboe: "This is the main pull request for block IO related changes for the 4.16 kernel. Nothing major in this pull request, but a good amount of improvements and fixes all over the map. This contains: - BFQ improvements, fixes, and cleanups from Angelo, Chiara, and Paolo. - Support for SMR zones for deadline and mq-deadline from Damien and Christoph. - Set of fixes for bcache by way of Michael Lyle, including fixes from himself, Kent, Rui, Tang, and Coly. - Series from Matias for lightnvm with fixes from Hans Holmberg, Javier, and Matias. Mostly centered around pblk, and the removing rrpc 1.2 in preparation for supporting 2.0. - A couple of NVMe pull requests from Christoph. Nothing major in here, just fixes and cleanups, and support for command tracing from Johannes. - Support for blk-throttle for tracking reads and writes separately. From Joseph Qi. A few cleanups/fixes also for blk-throttle from Weiping. - Series from Mike Snitzer that enables dm to register its queue more logically, something that's alwways been problematic on dm since it's a stacked device. - Series from Ming cleaning up some of the bio accessor use, in preparation for supporting multipage bvecs. - Various fixes from Ming closing up holes around queue mapping and quiescing. - BSD partition fix from Richard Narron, fixing a problem where we can't mount newer (10/11) FreeBSD partitions. - Series from Tejun reworking blk-mq timeout handling. The previous scheme relied on atomic bits, but it had races where we would think a request had timed out if it to reused at the wrong time. - null_blk now supports faking timeouts, to enable us to better exercise and test that functionality separately. From me. - Kill the separate atomic poll bit in the request struct. After this, we don't use the atomic bits on blk-mq anymore at all. From me. - sgl_alloc/free helpers from Bart. - Heavily contended tag case scalability improvement from me. - Various little fixes and cleanups from Arnd, Bart, Corentin, Douglas, Eryu, Goldwyn, and myself" * 'for-4.16/block' of git://git.kernel.dk/linux-block: (186 commits) block: remove smart1,2.h nvme: add tracepoint for nvme_complete_rq nvme: add tracepoint for nvme_setup_cmd nvme-pci: introduce RECONNECTING state to mark initializing procedure nvme-rdma: remove redundant boolean for inline_data nvme: don't free uuid pointer before printing it nvme-pci: Suspend queues after deleting them bsg: use pr_debug instead of hand crafted macros blk-mq-debugfs: don't allow write on attributes with seq_operations set nvme-pci: Fix queue double allocations block: Set BIO_TRACE_COMPLETION on new bio during split blk-throttle: use queue_is_rq_based block: Remove kblockd_schedule_delayed_work{,_on}() blk-mq: Avoid that blk_mq_delay_run_hw_queue() introduces unintended delays blk-mq: Rename blk_mq_request_direct_issue() into blk_mq_request_issue_directly() lib/scatterlist: Fix chaining support in sgl_alloc_order() blk-throttle: track read and write request individually block: add bdev_read_only() checks to common helpers block: fail op_is_write() requests to read-only partitions blk-throttle: export io_serviced_recursive, io_service_bytes_recursive ...

nvme_fcloop: refactor host/target io job access

2018-01-08T10:01:55Z

The split between what the host accesses on its flows vs what the target side accesses was flawed. Abort handling didn't properly clear initiator vs target structure cross-reference and locks weren't used for synchronization. Thus, there were issues of freeing structures too soon and access after free. A couple of these existed pre the IN_ISR mods, but when the target upcalls were converted to work items, thus adding delays between the 2 sides of accesses, the problems became pronounced. Resolve by: - tracking io state mainly in the tgt-side io structure. - make the tgt-side io structure released by reference not by code flow. - when changing initiator structures, use locks for synchronization - aborts are clearly tracked for which side saw the abort, and after seeing the abort, cross-references are cleared under lock. Signed-off-by: James Smart Signed-off-by: Christoph Hellwig

nvme_fcloop: rework to remove xxx_IN_ISR feature flags

2018-01-08T10:01:54Z

The existing fcloop driver expects the target side upcalls to the transport to context switch, thus the calls into the nvmet layer are not done in the calling context of the host/initiator down calls. The xxx_IN_ISR feature flags are used to select this logic. The xxx_IN_ISR feature flags should go away in the nvmet_fc transport as no other lldd utilizes them. Both Broadcom and Cavium lldds have their own non-ISR deferred handlers thus the nvmet calls can be made directly. This patch converts the paths that make the target upcalls (command receive, abort receive) such that they schedule a work item rather than expecting the transport to schedule the work item. The patch also cleans up the following: - The completion path from target to host scheduled a host work element called "work". Rename it "tio_done_work" for code clarity. - The abort io path called a iniwork item to call the host side io done. This is no longer needed as the abort routine can make the same call. Signed-off-by: James Smart Signed-off-by: Christoph Hellwig

nvme_fcloop: disassocate local port structs

2018-01-08T10:01:54Z

The current fcloop driver gets its lport structure from the private area co-allocated with the fc_localport. All is fine except the teardown path, which wants to wait on the completion, which is marked complete by the delete_localport callback performed after unregister_localport. The issue is, the nvme_fc transport frees the localport structure immediately after delete_localport is called, meaning the original routine is trying to wait on a complete that was just freed. Change such that a lport struct is allocated coincident with the addition and registration of a localport. The private area of the localport now contains just a backpointer to the real lport struct. Now, the completion can be waited for, and after completing, the new structure can be kfree'd. Signed-off-by: James Smart Signed-off-by: Christoph Hellwig

nvme_fcloop: fix abort race condition

2018-01-08T10:01:53Z

A test case revealed a race condition of an i/o completing on a thread parallel to the delete_association generating the aborts for the outstanding ios on the controller. The i/o completion was freeing the target fcloop context, thus the abort task referenced the just-freed memory. Correct by clearing the target/initiator cross pointers in the io completion and abort tasks before calling the callbacks. On aborts that detect already finished io's, ensure the complete context is called. Signed-off-by: James Smart Signed-off-by: Christoph Hellwig

nvme-fcloop: avoid possible uninitialized variable warning

2017-12-29T09:37:21Z

The kbuild test robot send mail of a potential use of an uninitialized variable - "tport" in fcloop_delete_targetport() which then calls __targetport_unreg() which uses the variable. It will never be the case it is uninitialized as the call to __targetport_unreg() only occurs if there is a valid nport pointer. And at the time the nport pointer is assigned, the tport variable is set. Remove the warning by assigning a NULL value initially. Signed-off-by: James Smart Signed-off-by: Christoph Hellwig