Commit Graph

713 Commits

Author SHA1 Message Date
Keith Busch
485783ca63 nvme: Make nvme user functions static
These functions are used only locally in the nvme core.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-30 14:59:34 +02:00
Keith Busch
b5d8af5b52 nvme/pci: Use req_op to determine DIF remapping
Only read and write commands need DIF remapping. Everything else uses
a passthrough integrity payload.

Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-30 14:59:33 +02:00
Christoph Hellwig
1cad65620f nvme: factor metadata handling out of __nvme_submit_user_cmd
Keep the metadata code in a separate helper instead of making the
main function more complicated.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-30 14:59:30 +02:00
Roland Dreier
489beb91e6 nvme-fabrics: Convert nvmf_transports_mutex to an rwsem
The mutex protects against the list of transports changing while a
controller is being created, but using a plain old mutex means that it
also serializes controller creation.  This unnecessarily slows down
creating multiple controllers - for example for the RDMA transport,
creating a controller involves establishing one connection for every IO
queue, which involves even more network/software round trips, so the
delay can become significant.

The simplest way to fix this is to change the mutex to an rwsem and only
hold it for writing when the list is being mutated.  Since we can take
the rwsem for reading while creating a controller, we can create multiple
controllers in parallel.

Signed-off-by: Roland Dreier <roland@purestorage.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-30 14:51:22 +02:00
Christoph Hellwig
1d5df6af8c nvme: don't blindly overwrite identifiers on disk revalidate
Instead validate that these identifiers do not change, as that is
prohibited by the specification.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
2017-08-29 10:23:04 +02:00
Christoph Hellwig
cdbff4f26b nvme: remove nvme_revalidate_ns
The function is used in two places, and the shared code for those will
diverge later in this series.

Instead factor out a new helper to get the ids for a namespace, simplify
the calling conventions for nvme_identify_ns and just open code the
sequence.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2017-08-29 10:22:39 +02:00
Christoph Hellwig
57eeaf8ec6 nvme: remove unused struct nvme_ns fields
And move the flags for the flags field near that field while touching
this area.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2017-08-29 10:22:26 +02:00
Christoph Hellwig
0a72bbba49 nvme: allow calling nvme_change_ctrl_state from irq context
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2017-08-29 10:22:23 +02:00
Christoph Hellwig
a751da3394 nvme: report more detailed status codes to the block layer
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
2017-08-29 10:22:18 +02:00
Martin K. Petersen
07fbd32a6b nvme: honor RTD3 Entry Latency for shutdowns
If an NVMe controller reports RTD3 Entry Latency larger than
shutdown_timeout, up to a maximum of 60 seconds, use that value to set
the shutdown timer. Otherwise fall back to the module parameter which
defaults to 5 seconds.

Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
[hch: removed do_div, made transition time local scope]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:44 +03:00
Jan H. Schönherr
5228b3280b nvme: fix uninitialized prp2 value on small transfers
The value of iod->first_dma ends up as prp2 in NVMe commands. In case
there is not enough data to cross a page boundary, iod->first_dma is
never initialized and contains random data.

Comply with the NVMe specification and fill in 0 in that case.

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:44 +03:00
Max Gurtovoy
a7b7c7a105 nvme-rdma: Use unlikely macro in the fast path
This patch slightly improves performance (mainly for small block sizes).

Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:43 +03:00
Martin Wilck
17c39d053a nvmet: use memcpy_and_pad for identify sn/fr
This changes the earlier patch "nvmet: don't report 0-bytes
in serial number" to use the memcpy_and_pad() helper introduced
in a previous patch.

Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Sagi Grimberg <sagi@grimbeg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:42 +03:00
James Smart
48fa362b6c nvmet-fc: simplify sg list handling
The existing nvmet_fc sg list handling has 2 faults:
a) the request between LLDD and transport has too large of an sg
   list (256 elements), which is normally 256k (64 elements).
b) sglist handling doesn't optimize on the fact that each element
   is a page.

This patch removes the static sg list in the request and uses the
dynamic list already present in the nvmet_fc transport. It also
simplies the handling of the sg list on multiple sequences to
take advantage of the per-page divisions.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:41 +03:00
James Smart
5533d42480 nvme-fc: Reattach to localports on re-registration
If the LLDD resets or detaches from an fc port, the LLDD will
deregister all remoteports seen by the fc port and deregister the
localport associated with the fc port. The teardown of the localport
structure will be held off due to reference counting until all the
remoteports are removed (and they are held off until all
controllers/associations to terminated). Currently, if the fc port
is reinit/reattached and registered again as a localport it is
treated as an independent entity from the prior localport and all
prior remoteports and controllers cannot be revived. They are
created as new and separate entities.

This patch changes the localport registration to look at the known
localports that are waiting to be torndown. If they are the same port
based on wwn's, the local port is transitioned out of the teardown
state.  This allows the remote ports and controller connections to
be reestablished and resumed as long as the localport can also be
reregistered within the timeout windows.

The patch adds a new routine nvme_fc_attach_to_unreg_lport() with
the functionality and moves the lport get/put routines to avoid
forward references.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:40 +03:00
Max Gurtovoy
60b43f627a nvme: rename AMS symbolic constants to fit specification
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:39 +03:00
Max Gurtovoy
ad4e05b24c nvme: add symbolic constants for CC identifiers
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:38 +03:00
Sagi Grimberg
caaa15c509 nvme: fix identify namespace logging
Use ctrl->device and lose the func name.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:38 +03:00
Guan Junxiong
9b483da15d nvme-fabrics: log a warning if hostid is invalid
This helps users to quickly spot the reason of why connection fails
if the hostid is not compliant with the uuid format.

Signed-off-by: Guan Junxiong <guanjunxiong@huawei.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:37 +03:00
Sagi Grimberg
09fdc23b29 nvme-rdma: call ops->reg_read64 instead of nvmf_reg_read64
To make the nvme_rdma_configure_admin_queue generic in preparation of
moving it to common code.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:36 +03:00
Sagi Grimberg
370ae6e450 nvme-rdma: cleanup error path in controller reset
No need to queue an extra work to indirect controller removal, just call the
ctrl remove routine.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:36 +03:00
Sagi Grimberg
68e16fcfaf nvme-rdma: introduce nvme_rdma_start_queue
This should pair with nvme_rdma_stop_queue.  While this is not a complete
inverse, it still pairs up pretty well because in fabrics we don't have a
disconnect capsule (yet) but we simply teardown the transport association.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:35 +03:00
Sagi Grimberg
41e8cfa117 nvme-rdma: rename nvme_rdma_init_queue to nvme_rdma_alloc_queue
Give it a name symmetric to nvme_rdma_free_queue. Also pass in the ctrl
sqsize+1 and not the opts queue_size.  And suppress a superflous
failure message.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:34 +03:00
Sagi Grimberg
148b4e7ff3 nvme-rdma: stop queues instead of simply flipping their state
If we move the queues from LIVE state, we might as well stop them (drain
for rdma).  Do it after we stop the request queues to prevent a stray
request sneaking in .queue_rq after we stop the queue.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:33 +03:00
Sagi Grimberg
a57bd54122 nvme-rdma: introduce configure/destroy io queues
Make a symmetrical handling with admin queue.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:33 +03:00
Sagi Grimberg
31fdf18401 nvme-rdma: reuse configure/destroy_admin_queue
No need to open-code it.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:32 +03:00
Sagi Grimberg
3f02fffb74 nvme-rdma: don't free tagset on resets
We're not supposed to do that.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 23:00:27 +03:00
Sagi Grimberg
18398af2dc nvme-rdma: disable the controller on resets
Mimic the pci driver as a controller disable might be more lightweight
than a shutdown.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:26 +02:00
Sagi Grimberg
b28a308ee7 nvme-rdma: move tagset allocation to a dedicated routine
We always pair tagset allocation with rdma device reference and it shares
some code, centralize it with an argument if its an admin or IO tagset.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:25 +02:00
Sagi Grimberg
34b6c2315e nvme: Add admin_tagset pointer to nvme_ctrl
Will be used when we centralize control flows.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:24 +02:00
Sagi Grimberg
90af35123d nvme-rdma: move nvme_rdma_configure_admin_queue code location
We will call it from other places so avoid having to forward declare it.
Also move it next to nvme_rdma_destroy_admin_queue.

Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:23 +02:00
Johannes Thumshirn
4897ad4e08 nvme-rdma: remove NVME_RDMA_MAX_SEGMENT_SIZE
NVME_RDMA_MAX_SEGMENT_SIZE is not used anywhere, zap it.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:22 +02:00
Johannes Thumshirn
1c35be8c8a nvmet-fcloop: remove ALL_OPTS define
ALL_OPTS isn't used anywhere, remove it.

Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:21 +02:00
Guan Junxiong
130c24b5be nvmet: fix the return error code of target if host is not allowed
nvmf target shall return NVME_SC_CONNECT_INVALID_HOST instead of
the gereal code INVALID_PARAM when the given host nqn is not allowed
to connect. Refer to the 2.2.1 section of the NVMe over Fabrics Spec.

Signed-off-by: Guan Junxiong <guanjunxiong@huawei.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:20 +02:00
Christoph Hellwig
1645d5036f nvmet: use NVME_NSID_ALL
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
2017-08-28 21:38:19 +02:00
Jon Derrick
dbf86b3900 nvme: add support for NVMe 1.3 Timestamp Feature
NVME's Timestamp feature allows controllers to be aware of the epoch
time in milliseconds. This patch adds the set features hook for various
transports through the identify path, so that resets and resumes can
update the controller as necessary.

Signed-off-by: Jon Derrick <jonathan.derrick@intel.com>
[hch: rebased on top of nvme-4.13 error handling changes,
      changed nvme_configure_timestamp to return the status]
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-28 21:38:18 +02:00
Arnav Dawn
62346eaeb2 nvme: define NVME_NSID_ALL
Define the constant "0xffffffff" (used as nsid for all namespaces)
as NVME_NSID_ALL.

Signed-off-by: Arnav Dawn <a.dawn@samsung.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-08-28 21:38:17 +02:00
Arnav Dawn
b6dccf7fae nvme: add support for FW activation without reset
This patch adds support for handling Fw activation without reset
On completion of FW-activation-starting AER, all queues are
paused till CSTS.PP is cleared or timed out (exceeds max time for
fw activtion MTFA). If device fails to clear CSTS.PP within MTFA,
driver issues reset controller.

Signed-off-by: Arnav Dawn <a.dawn@samsung.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
2017-08-28 21:38:17 +02:00
Jens Axboe
cd996fb47c Linux 4.13-rc7
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Merge tag 'v4.13-rc7' into for-4.14/block-postmerge

Linux 4.13-rc7

Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-28 13:00:44 -06:00
Christoph Hellwig
74d46992e0 block: replace bi_bdev with a gendisk pointer and partitions index
This way we don't need a block_device structure to submit I/O.  The
block_device has different life time rules from the gendisk and
request_queue and is usually only available when the block device node
is open.  Other callers need to explicitly create one (e.g. the lightnvm
passthrough code, or the new nvme multipathing code).

For the actual I/O path all that we need is the gendisk, which exists
once per block device.  But given that the block layer also does
partition remapping we additionally need a partition index, which is
used for said remapping in generic_make_request.

Note that all the block drivers generally want request_queue or
sometimes the gendisk, so this removes a layer of indirection all
over the stack.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-23 12:49:55 -06:00
Bart Van Assche
d352ae205d blk-mq: Make blk_mq_reinit_tagset() calls easier to read
Since blk_mq_ops.reinit_request is only called from inside
blk_mq_reinit_tagset(), make this function pointer an argument of
blk_mq_reinit_tagset() instead of a member of struct blk_mq_ops.
This patch does not change any functionality but makes
blk_mq_reinit_tagset() calls easier to read and to analyze.

Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Hannes Reinecke <hare@suse.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Sagi Grimberg <sagi@grimberg.me>
Cc: James Smart <james.smart@broadcom.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
2017-08-18 08:36:58 -06:00
Keith Busch
e9d8a0fdea nvme-pci: set cqe_seen on polled completions
Fixes: 920d13a884 ("nvme-pci: factor out the cqe reading mechanics from __nvme_process_cq")
Reported-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-18 09:19:39 +02:00
Christoph Hellwig
81a0b8d74e nvme-fabrics: fix reporting of unrecognized options
Only print the specified options that are not recognized, instead
of the whole list of options.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Max Gurtovoy <maxg@mellanox.com>
2017-08-17 18:48:54 +02:00
James Smart
369157b41c nvmet-fc: eliminate incorrect static markers on local variables
There were 2 statics introduced that were bogus. Removed the static
designations.

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-17 09:35:08 +02:00
James Smart
16a5a480f0 nvmet-fc: correct use after free on list teardown
Use list_for_each_entry_safe to prevent list handling from referencing
next pointers directly after list_del's

Signed-off-by: James Smart <james.smart@broadcom.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-16 10:06:18 +02:00
Martin Wilck
42819eb7a0 nvmet: don't overwrite identify sn/fr with 0-bytes
The merged version of my patch "nvmet: don't report 0-bytes in serial
number" fails to remove two lines which should have been replaced,
so that the space-padded strings are overwritten again with 0-bytes.
Fix it.

Fixes: 42de82a8b5 nvmet: don't report 0-bytes in serial number
Signed-off-by: Martin Wilck <mwilck@suse.com>
Reviewed-by: Sagi Grimberg <sagi@grimbeg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-16 10:06:10 +02:00
Kwan (Hingkwan) Huen-SSI
a082b42628 nvme: fix directive command numd calculation
The numd field of directive receive command takes number of dwords to
transfer. This fix has the correct calculation for numd.

Signed-off-by: Kwan (Hingkwan) Huen-SSI <kwan.huen@samsung.com>
Reviewed-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-10 19:53:44 +02:00
Keith Busch
634b832590 nvme: fix nvme reset command timeout handling
We need to return an error if a timeout occurs on any NVMe command during
initialization. Without this, the nvme reset work will be stuck. A timeout
will have a negative error code, meaning we need to stop initializing
the controller. All postitive returns mean the controller is still usable.

bugzilla: https://bugzilla.kernel.org/show_bug.cgi?id=196325

Signed-off-by: Keith Busch <keith.busch@intel.com>
Cc: Martin Peres <martin.peres@intel.com>
[jth consolidated cleanup path ]
Signed-off-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-10 19:53:38 +02:00
Max Gurtovoy
1c78f7735b nvme-pci: fix CMB sysfs file removal in reset path
Currently we create the sysfs entry even if we fail mapping
it. In that case, the unmapping will not remove the sysfs created
file. There is no good reason to create a sysfs entry for a non
working CMB and show his characteristics.

Fixes: f63572dff ("nvme: unmap CMB and remove sysfs file in reset path")
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Stephen Bates <sbates@raithlin.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-10 11:19:06 +02:00
James Smart
0fb228d30b nvmet_fc: add defer_req callback for deferment of cmd buffer return
At queue creation, the transport allocates a local job struct
(struct nvmet_fc_fcp_iod) for each possible element of the queue.
When a new CMD is received from the wire, a jobs struct is allocated
from the queue and then used for the duration of the command.
The job struct contains buffer space for the wire command iu. Thus,
upon allocation of the job struct, the cmd iu buffer is copied to
the job struct and the LLDD may immediately free/reuse the CMD IU
buffer passed in the call.

However, in some circumstances, due to the packetized nature of FC
and the api of the FC LLDD which may issue a hw command to send the
wire response, but the LLDD may not get the hw completion for the
command and upcall the nvmet_fc layer before a new command may be
asynchronously received on the wire. In other words, its possible
for the initiator to get the response from the wire, thus believe a
command slot free, and send a new command iu. The new command iu
may be received by the LLDD and passed to the transport before the
LLDD had serviced the hw completion and made the teardown calls for
the original job struct. As such, there is no available job struct
available for the new io. E.g. it appears like the host sent more
queue elements than the queue size. It didn't based on it's
understanding.

Rather than treat this as a hard connection failure queue the new
request until the job struct does free up. As the buffer isn't
copied as there's no job struct, a special return value must be
returned to the LLDD to signify to hold off on recycling the cmd
iu buffer.  And later, when a job struct is allocated and the
buffer copied, a new LLDD callback is introduced to notify the
LLDD and allow it to recycle it's command iu buffer.

Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2017-08-10 11:06:38 +02:00