Commit Graph

9 Commits

Author SHA1 Message Date
Bart Van Assche
1b63327734 nvmet-fc: Remove a set-but-not-used variable
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>
2017-06-15 14:30:25 +02:00
James Smart
4b8ba5fa52 nvmet-fc: remove target cpu scheduling flag
Remove NVMET_FCTGTFEAT_NEEDS_CMD_CPUSCHED. It's unnecessary.

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
2017-05-20 10:11:34 -06:00
Christoph Hellwig
36b8890e91 nvmet-fcloop: mark two symbols static
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>
2017-04-24 09:18:27 +02:00
James Smart
a97ec51b37 nvmet_fc: Rework target side abort handling
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>
2017-04-21 16:41:51 +02:00
James Smart
ce79bfc2c7 nvme_fcloop: split job struct from transport for req_release
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>
2017-04-21 16:41:50 +02:00
James Smart
19b58d9473 nvmet_fc: add req_release to lldd api
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>
2017-04-21 16:41:49 +02:00
James Smart
39498faef7 nvmet_fc: add target feature flags for upcall isr contexts
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>
2017-04-21 16:41:48 +02:00
Colin Ian King
7c3a23b85c nvmet/fcloop: remove some logically dead code performing redundant ret checks
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>
2016-12-21 11:34:28 +01:00
James Smart
475d0fe795 nvme-fabrics: Add FC LLDD loopback driver to test FC-NVME
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>
2016-12-06 14:51:48 +01:00