With additional debugging enabled, seeing warnings for suspicious RCU
usage or Sleeping function called from invalid context.
These both map to allocation of a work structure which is currently
GFP_KERNEL, meaning it can sleep. For the RCU warning, the sequence was
sleeping while holding the RCU lock.
Convert the allocation to GFP_ATOMIC.
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
With extra debug on, inconsistent lock state warnings are being called
out as the tfcp_req->reqlock is being taken out without irq, while some
calling sequences have the sequence in a softirq state.
Change the lock taking/release to raise/drop irq.
Signed-off-by: James Smart <jsmart2021@gmail.com>
Reviewed-by: Minwoo Im <minwoo.im.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Update fcloop to support the discovery_event operation and
invoke a nvme rescan. In a real fc adapter, this would generate an
RSCN, which the host would receive and convert into a nvme rescan
on the remote port specified in the rscn payload.
Signed-off-by: James Smart <jsmart2021@gmail.com>
[kbuild-bot: fcloop_tgt_discovery_evt can be static]
Reviewed-by: Hannes Reinecke <hare@suse.com>
Reviewed-by: Arun Easi <aeasi@marvell.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Update license to use SPDX-License-Identifier instead of verbose license
text.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
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 <bvanassche@acm.org>
Reviewed-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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 <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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
...
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 <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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 <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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 <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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 <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
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 <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Now that there are potentially long delays between when a remoteport or
targetport delete calls is made and when the callback occurs (dev_loss_tmo
timeout), no longer block in the delete routines and move the final nport
puts to the callbacks.
Moved the fcloop_nport_get/put/free routines to avoid forward declarations.
Ensure port_info structs used in registrations are nulled in case fields
are not set (ex: devloss_tmo values).
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
The FC-NVME transport loopback test module used the FC-specific error
codes in cases where it emulated a transport abort case. Instead of
using the FC-specific values, now use a generic value (NVME_SC_INTERNAL).
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This was detected by building the nvmet-fc driver with W=1.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: James Smart <james.smart@broadcom.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Found by sparse.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
target transport:
----------------------
There are cases when there is a need to abort in-progress target
operations (writedata) so that controller termination or errors can
clean up. That can't happen currently as the abort is another target
op type, so it can't be used till the running one finishes (and it may
not). Solve by removing the abort op type and creating a separate
downcall from the transport to the lldd to request an io to be aborted.
The transport will abort ios on queue teardown or io errors. In general
the transport tries to call the lldd abort only when the io state is
idle. Meaning: ops that transmit data (readdata or rsp) will always
finish their transmit (or the lldd will see a state on the
link or initiator port that fails the transmit) and the done call for
the operation will occur. The transport will wait for the op done
upcall before calling the abort function, and as the io is idle, the
io can be cleaned up immediately after the abort call; Similarly, ios
that are not waiting for data or transmitting data must be in the nvmet
layer being processed. The transport will wait for the nvmet layer
completion before calling the abort function, and as the io is idle,
the io can be cleaned up immediately after the abort call; As for ops
that are waiting for data (writedata), they may be outstanding
indefinitely if the lldd doesn't see a condition where the initiatior
port or link is bad. In those cases, the transport will call the abort
function and wait for the lldd's op done upcall for the operation, where
it will then clean up the io.
Additionally, if a lldd receives an ABTS and matches it to an outstanding
request in the transport, A new new transport upcall was created to abort
the outstanding request in the transport. The transport expects any
outstanding op call (readdata or writedata) will completed by the lldd and
the operation upcall made. The transport doesn't act on the reported
abort (e.g. clean up the io) until an op done upcall occurs, a new op is
attempted, or the nvmet layer completes the io processing.
fcloop:
----------------------
Updated to support the new target apis.
On fcp io aborts from the initiator, the loopback context is updated to
NULL out the half that has completed. The initiator side is immediately
called after the abort request with an io completion (abort status).
On fcp io aborts from the target, the io is stopped and the initiator side
sees it as an aborted io. Target side ops, perhaps in progress while the
initiator side is done, continue but noop the data movement as there's no
structure on the initiator side to reference.
patch also contains:
----------------------
Revised lpfc to support the new abort api
commonized rsp buffer syncing and nulling of private data based on
calling paths.
errors in op done calls don't take action on the fod. They're bad
operations which implies the fod may be bad.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Current design has the fcloop job struct, used for both initiator and
target processing, allocated as part of the initiator request structure.
On aborts, the initiator side (based on the request) may terminate, yet
the target side wants to continue processing. the target side can't do
that if the initiator side goes away.
Revise fcloop to allocate an independent target side structure when it
starts an io from the initiator.
Added a lock to the request struct as well to synchronize pointer updates
on abort calls.
Modified target downcalls to recognize conditions where initiator has
aborted the io (thus nulled the pointer between job structs), thus
avoid referencing sgl lists which are gone and no longer making upcalls
to the initiator.
In conditions where the targetport is no longer connected, have the
initiator return an access failure rather than simulating a command
completion.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
With the advent of the opdone calls changing context, the lldd can no
longer assume that once the op->done call returns for RSP operations
that the request struct is no longer being accessed.
As such, revise the lldd api for a req_release callback that the
transport will call when the job is complete. This will also be used
with abort cases.
Fixed text in api header for change in io complete semantics.
Revised lpfc to support the new req_release api.
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Two new feature flags were added to control whether upcalls to the
transport result in context switches or stay in the calling context.
NVMET_FCTGTFEAT_CMD_IN_ISR:
By default, if the flag is not set, the transport assumes the
lldd is in a non-isr context and in the cpu context it should be
for the io queue. As such, the cmd handler is called directly in the
calling context.
If the flag is set, indicating the upcall is an isr context, the
transport mandates a transition to a workqueue. The workqueue assigned
to the queue is used for the context.
NVMET_FCTGTFEAT_OPDONE_IN_ISR
By default, if the flag is not set, the transport assumes the
lldd is in a non-isr context and in the cpu context it should be
for the io queue. As such, the fcp operation done callback is called
directly in the calling context.
If the flag is set, indicating the upcall is an isr context, the
transport mandates a transition to a workqueue. The workqueue assigned
to the queue is used for the context.
Updated lpfc for flags
Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
The check to see if ret is non-zero and return this rather than count
is redundant in two occassions. It is redundant because prior to this
check, the return code ret is already checked for a non-zero error
return value and we return from the function at that point.
Signed-off-by: Colin Ian King <colin.king@canonical.com>
Reviewed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Add FC LLDD loopback driver to test FC host and target transport within
nvme-fabrics
To aid in the development and testing of the lower-level api of the FC
transport, this loopback driver has been created to act as if it were a
FC hba driver supporting both the host interfaces as well as the target
interfaces with the nvme FC transport.
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Jay Freyensee <james_p_freyensee@linux.intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
James Smart
Christoph Hellwig
Bart Van Assche
Linus Torvalds
Johannes Thumshirn
Bart Van Assche
Colin Ian King