linux.git/drivers/nvme/host/fc.c, branch v4.13

nvme-fc: revise TRADDR parsing

2017-07-25T16:05:25+00:00

The FC-NVME spec hasn't locked down on the format string for TRADDR.
Currently the spec is lobbying for "nn-<16hexdigits>:pn-<16hexdigits>"
where the wwn's are hex values but not prefixed by 0x.

Most implementations so far expect a string format of
"nn-0x<16hexdigits>:pn-0x<16hexdigits>" to be used. The transport
uses the match_u64 parser which requires a leading 0x prefix to set
the base properly. If it's not there, a match will either fail or return
a base 10 value.

The resolution in T11 is pushing out. Therefore, to fix things now and
to cover any eventuality and any implementations already in the field,
this patch adds support for both formats.

The change consists of replacing the token matching routine with a
routine that validates the fixed string format, and then builds
a local copy of the hex name with a 0x prefix before calling
the system parser.

Note: the same parser routine exists in both the initiator and target
transports. Given this is about the only "shared" item, we chose to
replicate rather than create an interdendency on some shared code.

Signed-off-by: James Smart 
Signed-off-by: Christoph Hellwig

nvme-fc: address target disconnect race conditions in fcp io submit

2017-07-25T15:58:47+00:00

There are cases where threads are in the process of submitting new
io when the LLDD calls in to remove the remote port. In some cases,
the next io actually goes to the LLDD, who knows the remoteport isn't
present and rejects it. To properly recovery/restart these i/o's we
don't want to hard fail them, we want to treat them as temporary
resource errors in which a delayed retry will work.

Add a couple more checks on remoteport connectivity and commonize the
busy response handling when it's seen.

Signed-off-by: James Smart 
Signed-off-by: Christoph Hellwig

nvme: split nvme_uninit_ctrl into stop and uninit

2017-07-06T06:49:42+00:00

Usually before we teardown the controller we want to:
1. complete/cancel any ctrl inflight works
2. remove ctrl namespaces (only for removal though, resets
   shouldn't remove any namespaces).

but we do not want to destroy the controller device as
we might use it for logging during the teardown stage.

This patch adds nvme_start_ctrl() which queues inflight
controller works (aen, ns scan, queue start and keep-alive
if kato is set) and nvme_stop_ctrl() which cancels the works
namespace removal is left to the callers to handle.

Move nvme_uninit_ctrl after we are done with the
controller device.

Reviewed-by: Keith Busch 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Sagi Grimberg

nvme-fc: quiesce/unquiesce admin_q instead of start/stop its hw queues

2017-07-06T06:48:31+00:00

unlike blk_mq_stop_hw_queues and blk_mq_start_stopped_hw_queues
quiescing/unquiescing respects the submission path rcu grace.

Also, make sure to unquiesce before cleanup the admin queue.

Reviewed-by: Ming Lei 
Reviewed-By: James Smart 
Signed-off-by: Sagi Grimberg

nvme-fc: use blk_mq_delay_run_hw_queue instead of open-coding it

2017-07-04T07:44:46+00:00

Cc: James Smart 
Signed-off-by: Sagi Grimberg

nvme-fc: update tagset nr_hw_queues after queues reinit

2017-07-04T06:44:17+00:00

We might have more/less queues once we reconnect/reset. For
example due to cpu going online/offline or controller constraints.

Reviewed-by: Johannes Thumshirn 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Sagi Grimberg

nvme-fc: don't override opts->nr_io_queues

2017-07-04T06:43:26+00:00

Its what the user passed, so its probably a better
idea to keep it intact. Also, limit the number of
I/O queues to max online cpus and the lport maximum
hw queues.

Reviewed-by: Johannes Thumshirn 
Reviewed-by: Max Gurtovoy 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Sagi Grimberg

nvme: move ctrl cap to struct nvme_ctrl

2017-07-02T12:03:22+00:00

All transports use either a private cache of controller cap or an on-stack
copy, move it to the generic struct nvme_ctrl. In the future it will also
be maintained by the core.

Reviewed-by: Christoph Hellwig 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Max Gurtovoy 
Signed-off-by: Sagi Grimberg

nvme: move queue_count to the nvme_ctrl

2017-07-02T11:59:04+00:00

All all transports use the queue_count in exactly the same, so move it to
the generic struct nvme_ctrl. In the future it will also be maintained by
the core.

Reviewed-by: Christoph Hellwig 
Reviewed-By: James Smart 
Reviewed-by: Johannes Thumshirn 
Reviewed-by: Max Gurtovoy 
Signed-off-by: Sagi Grimberg

nvme_fc: fix error recovery on link down.

2017-06-28T14:14:13+00:00

Currently, the fc transport invokes nvme_fc_error_recovery() on every
io in which the transport detects an error.  Which means:
a) it's really noisy on large io loads that all get hit by a link down.
b) we repeatively call nvme_stop_queues() even though queues are
 stopped upon the first error or as first steps of reset_work.

Correct by:
Errors are only meaningful if the controller is in the LIVE state.
Thus, enact the reset_work only if LIVE. If called repeatively, state
will have already transitioned.
There's no need to stop the queues here. Let the first steps of
reset_work do the queue stopping.

Signed-off-by: James Smart 
Signed-off-by: Sagi Grimberg 
Signed-off-by: Jens Axboe