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Pull block layer updates from Jens Axboe:
"This is the main block pull request this series. Contrary to previous
release, I've kept the core and driver changes in the same branch. We
always ended up having dependencies between the two for obvious
reasons, so makes more sense to keep them together. That said, I'll
probably try and keep more topical branches going forward, especially
for cycles that end up being as busy as this one.
The major parts of this pull request is:
- Improved support for O_DIRECT on block devices, with a small
private implementation instead of using the pig that is
fs/direct-io.c. From Christoph.
- Request completion tracking in a scalable fashion. This is utilized
by two components in this pull, the new hybrid polling and the
writeback queue throttling code.
- Improved support for polling with O_DIRECT, adding a hybrid mode
that combines pure polling with an initial sleep. From me.
- Support for automatic throttling of writeback queues on the block
side. This uses feedback from the device completion latencies to
scale the queue on the block side up or down. From me.
- Support from SMR drives in the block layer and for SD. From Hannes
and Shaun.
- Multi-connection support for nbd. From Josef.
- Cleanup of request and bio flags, so we have a clear split between
which are bio (or rq) private, and which ones are shared. From
Christoph.
- A set of patches from Bart, that improve how we handle queue
stopping and starting in blk-mq.
- Support for WRITE_ZEROES from Chaitanya.
- Lightnvm updates from Javier/Matias.
- Supoort for FC for the nvme-over-fabrics code. From James Smart.
- A bunch of fixes from a whole slew of people, too many to name
here"
* 'for-4.10/block' of git://git.kernel.dk/linux-block: (182 commits)
blk-stat: fix a few cases of missing batch flushing
blk-flush: run the queue when inserting blk-mq flush
elevator: make the rqhash helpers exported
blk-mq: abstract out blk_mq_dispatch_rq_list() helper
blk-mq: add blk_mq_start_stopped_hw_queue()
block: improve handling of the magic discard payload
blk-wbt: don't throttle discard or write zeroes
nbd: use dev_err_ratelimited in io path
nbd: reset the setup task for NBD_CLEAR_SOCK
nvme-fabrics: Add FC LLDD loopback driver to test FC-NVME
nvme-fabrics: Add target support for FC transport
nvme-fabrics: Add host support for FC transport
nvme-fabrics: Add FC transport LLDD api definitions
nvme-fabrics: Add FC transport FC-NVME definitions
nvme-fabrics: Add FC transport error codes to nvme.h
Add type 0x28 NVME type code to scsi fc headers
nvme-fabrics: patch target code in prep for FC transport support
nvme-fabrics: set sqe.command_id in core not transports
parser: add u64 number parser
nvme-rdma: align to generic ib_event logging helper
...
Instead of allocating a single unused biovec for discard requests, send
them down without any payload. Instead we allow the driver to add a
"special" payload using a biovec embedded into struct request (unioned
over other fields never used while in the driver), and overloading
the number of segments for this case.
This has a couple of advantages:
- we don't have to allocate the bio_vec
- the amount of special casing for discard requests in the block
layer is significantly reduced
- using this same scheme for other request types is trivial,
which will be important for implementing the new WRITE_ZEROES
op on devices where it actually requires a payload (e.g. SCSI)
- we can get rid of playing games with the request length, as
we'll never touch it and completions will work just fine
- it will allow us to support ranged discard operations in the
future by merging non-contiguous discard bios into a single
request
- last but not least it removes a lot of code
This patch is the common base for my WIP series for ranges discards and to
remove discard_zeroes_data in favor of always using REQ_OP_WRITE_ZEROES,
so it would be good to get it in quickly.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
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>
Implements the FC-NVME T11 definition of how nvme fabric capsules are
performed on an FC fabric. Utilizes a lower-layer API to FC host adapters
to send/receive FC-4 LS operations and perform the FCP transactions
necessary to perform and FCP IO request for NVME.
The T11 definitions for FC-4 Link Services are implemented which create
NVMeOF connections. Implements the hooks with nvmet layer to pass NVME
commands to it for processing and posting of data/response base to the
host via the different connections.
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>
Implements the FC-NVME T11 definition of how nvme fabric capsules are
performed on an FC fabric. Utilizes a lower-layer API to FC host adapters
to send/receive FC-4 LS operations and FCP operations that comprise NVME
over FC operation.
The T11 definitions for FC-4 Link Services are implemented which create
NVMeOF connections. Implements the hooks with blk-mq to then submit admin
and io requests to the different connections.
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>
- Add FC transport type decoding
- Add FC address family decoding
Signed-off-by: James Smart <james.smart@broadcom.com>
Acked-by: Johannes Thumshirn <jth@kernel.org>
Reviewed-by: Jay Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Currently, core.c sets command_id only on rd/wr commands, leaving it to
the transport to set it again to ensure the request had a command id.
Move location of set in core so applies to all commands.
Remove transport sets.
Signed-off-by: James Smart <james.smart@broadcom.com>
Reviewed-by: Jay Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Reviewed-by: Jay Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
Adjust indentation such that arguments are aligned.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
When removing a namespace we delete it from the subsystem namespaces
list with list_del_init which allows us to know if it is enabled or
not.
The problem is that list_del_init initialize the list next and does
not respect the RCU list-traversal we do on the IO path for locating
a namespace. Instead we need to use list_del_rcu which is allowed to
run concurrently with the _rcu list-traversal primitives (keeps list
next intact) and guarantees concurrent nvmet_find_naespace forward
progress.
By changing that, we cannot rely on ns->dev_link for knowing if the
namspace is enabled, so add enabled indicator entry to nvmet_ns for
that.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Solganik Alexander <sashas@lightbitslabs.com>
Cc: <stable@vger.kernel.org> # v4.8+
Queue size needs to respect the Maximum Queue Entries Supported advertised by
the controller in its Capability register.
Signed-off-by: Samuel Jones <sjones@kalray.eu>
Reviewed-by: Christoph Hellwig <hch@lst.de>
[sagig: fixed queue_size adjustment according to
Daniel Verkamp <daniel.verkamp@intel.com> comment]
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
nvmet_sq_init() returns a value <= 0. nvmet_rdma_cm_reject() expects
a second argument that is a NVME_RDMA_CM_* constant. Hence this patch.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Sagi Grimberg <sagi@grimbeg.me>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Add support for handling write zeroes command on target.
Call into __blkdev_issue_zeroout, which the block layer expands into the
best suitable variant of zeroing the LBAs. Allow write zeroes operation
to deallocate the LBAs when calling __blkdev_issue_zeroout.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@hgst.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Allow write zeroes operations (REQ_OP_WRITE_ZEROES) on the block
device, if the device supports optional command bit set for write
zeroes. Add support to setup write zeroes command. Set maximum possible
write zeroes sectors in one write zeroes command according to
nvme write zeroes command definition.
Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni@hgst.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
In order to naturally support multi-target instances on an Open-Channel
SSD, targets should own the LUNs they get blocks from and manage
provisioning internally. This is done in several steps.
Since targets own the LUNs the are instantiated on top of and manage the
free block list internally, there is no need for a LUN abstraction in
the media manager. LUNs are intrinsically managed as in the physical
layout (ch:0,lun:0, ..., ch:0,lun:n, ch:1,lun:0, ch:1,lun:n, ...,
ch:m,lun:0, ch:m,lun:n) and given to the targets based on the target
creation ioctl. This simplifies LUN management and clears the path for a
partition manager to sit directly underneath LightNVM targets.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
In order to naturally support multi-target instances on an Open-Channel
SSD, targets should own the LUNs they get blocks from and manage
provisioning internally. This is done in several steps.
This patch moves the block provisioning inside of the target and removes
the get/put block interface from the media manager.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Erases might be subject to host hints. An example is multi-plane
programming to erase blocks in parallel. Enable targets to specify this
hint.
Signed-off-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Previously, LBA read and write were not supported in the lightnvm
specification. Now that it supports it, lets use the traditional
NVMe gendisk, and attach the lightnvm sysfs geometry export.
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
When struct nvme_request was introduced, the nvme_nvm_submit_io was
converted to the new interface. The interface moves nvme_nvm_command
data structure into the struct request pdu. On io completion, rq->cmd is
freed, which should have been the dereferenced pdu nvme_request->cmd.
Fixes: d49187e97e "nvme: introduce struct nvme_request"
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Some drivers often use external bvec table, so introduce
this helper for this case. It is always safe to access the
bio->bi_io_vec in this way for this case.
After converting to this usage, it will becomes a bit easier
to evaluate the remaining direct access to bio->bi_io_vec,
so it can help to prepare for the following multipage bvec
support.
Signed-off-by: Ming Lei <tom.leiming@gmail.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Fixed up the new O_DIRECT cases.
Signed-off-by: Jens Axboe <axboe@fb.com>
The nvme_remove function tears down all allocated resources in the correct
order, so no need to free queues on error during initialization. This
fixes possible use-after-free errors when queues are still associated
with a blk-mq hctx.
Reported-by: Scott Bauer <scott.bauer@intel.com>
Tested-by: Scott Bauer <scott.bauer@intel.com>
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimbeg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: stable@vger.kernel.org
Signed-off-by: Jens Axboe <axboe@fb.com>
Let's not depend on any of the BLK_MQ_RQ_QUEUE_* constants having
specific values. No functional change.
Signed-off-by: Omar Sandoval <osandov@fb.com>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
draining the qp right after disconnect might not suffice because
the nvmet sq is not fully drained (in nvmet_sq_destroy) and we might
see completions after the drain. Instead, drain right before the
qp destroy which comes after the sq destruction and we can be sure
that no posts come after the drain.
Tested-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
While testing nvme-rdma with the spdk nvmf target over iw_cxgb4, I
configured the target (mistakenly) to generate an error creating the
NVMF IO queues. This resulted a "Invalid SQE Parameter" error sent back
to the host on the first IO queue connect:
[ 9610.928182] nvme nvme1: queue_size 128 > ctrl maxcmd 120, clamping down
[ 9610.938745] nvme nvme1: creating 32 I/O queues.
So nvmf_connect_io_queue() returns an error to
nvmf_connect_io_queue() / nvmf_connect_io_queues(), and that
is returned to nvme_rdma_create_io_queues(). In the error path,
nvmf_rdma_create_io_queues() frees the queue tagset memory _before_
stopping and freeing the IB queues, which causes yet another
touch-after-free crash due to SQ CQEs being flushed after the ib_cqe
structs pointed-to by the flushed WRs have been freed (since they are
part of the nvme_rdma_request struct).
The fix is to stop and free the queues in nvmf_connect_io_queues()
if there is an error connecting any of the queues.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
In case we accepted a queue connection and it failed, we might not
remove the queue from the list until we unload and clean it up.
We should delete it from the queue list on the relevant handler.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
In the transport, in case of an interal queue error like
error completion in rdma we trigger a fatal error. However,
multiple queues in the same controller can serr error completions
and we don't want to trigger fatal error work more than once.
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
If we reconncect we might have command queue up that get resent as soon
as the queue is restarted. But until the connect command succeeded we
can't send other command. Add a new flag that marks a queue as live when
connect finishes, and delay any non-connect command until the queue is
live based on it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reported-by: Steve Wise <swise@opengridcomputing.com>
Tested-by: Steve Wise <swise@opengridcomputing.com>
[sagig: fixes admin queue LIVE setting]
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
When we initiate queue teardown sequence we call rdma_destroy_qp
which clears cm_id->qp, afterwards we call rdma_destroy_id, but
we might see a rdma_cm event in between with a cleared cm_id->qp
so watch out for that and silently ignore the event because this
means that the queue teardown sequence is in progress.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
The ns->lba_shift assumes its value to be the logarithmic of the
LA size. A previous patch duplicated the lba_shift calculation into
lightnvm. It prematurely also subtracted a 512byte shift, which commonly
is applied per-command. The 512byte shift being subtracted twice led to
data loss when restoring the logical to physical mapping table from
device and when issuing I/O commands using rrpc.
Fix offset by removing the 512byte shift subtraction when calculating
lba_shift.
Fixes: b0b4e09c1a "lightnvm: control life of nvm_dev in driver"
Reported-by: Javier González <javier@cnexlabs.com>
Signed-off-by: Matias Bjørling <m@bjorling.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
The poll code is blk-mq specific, let's move it to blk-mq.c. This
is a prep patch for improving the polling code.
Signed-off-by: Jens Axboe <axboe@fb.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
We only need the status and result fields, and passing them explicitly
makes life a lot easier for the Fibre Channel transport which doesn't
have a full CQE for the fast path case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
This adds a shared per-request structure for all NVMe I/O. This structure
is embedded as the first member in all NVMe transport drivers request
private data and allows to implement common functionality between the
drivers.
The first use is to replace the current abuse of the SCSI command
passthrough fields in struct request for the NVMe command passthrough,
but it will grow a field more fields to allow implementing things
like common abort handlers in the future.
The passthrough commands are handled by having a pointer to the SQE
(struct nvme_command) in struct nvme_request, and the union of the
possible result fields, which had to be turned from an anonymous
into a named union for that purpose. This avoids having to pass
a reference to a full CQE around and thus makes checking the result
a lot more lightweight.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Make nvme_requeue_req() check BLK_MQ_S_STOPPED instead of
QUEUE_FLAG_STOPPED. Remove the QUEUE_FLAG_STOPPED manipulations
that became superfluous because of this change. Change
blk_queue_stopped() tests into blk_mq_queue_stopped().
This patch fixes a race condition: using queue_flag_clear_unlocked()
is not safe if any other function that manipulates the queue flags
can be called concurrently, e.g. blk_cleanup_queue().
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Avoid that nvme_queue_rq() is still running when nvme_stop_queues()
returns.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Most blk_mq_requeue_request() and blk_mq_add_to_requeue_list() calls
are followed by kicking the requeue list. Hence add an argument to
these two functions that allows to kick the requeue list. This was
proposed by Christoph Hellwig.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@fb.com>
Since blk_mq_requeue_work() no longer restarts stopped queues
canceling requeue work is no longer needed to prevent that a
stopped queue would be restarted. Hence remove this function.
Signed-off-by: Bart Van Assche <bart.vanassche@sandisk.com>
Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Keith Busch <keith.busch@intel.com>
Cc: Hannes Reinecke <hare@suse.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Remove the WRITE_* and READ_SYNC wrappers, and just use the flags
directly. Where applicable this also drops usage of the
bio_set_op_attrs wrapper.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
A lot of the REQ_* flags are only used on struct requests, and only of
use to the block layer and a few drivers that dig into struct request
internals.
This patch adds a new req_flags_t rq_flags field to struct request for
them, and thus dramatically shrinks the number of common requests. It
also removes the unfortunate situation where we have to fit the fields
from the same enum into 32 bits for struct bio and 64 bits for
struct request.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Shaun Tancheff <shaun.tancheff@seagate.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
Pull block fixes from Jens Axboe:
"A set of fixes that missed the merge window, mostly due to me being
away around that time.
Nothing major here, a mix of nvme cleanups and fixes, and one fix for
the badblocks handling"
* 'for-linus' of git://git.kernel.dk/linux-block:
nvmet: use symbolic constants for CNS values
nvme: use symbolic constants for CNS values
nvme.h: add an enum for cns values
nvme.h: don't use uuid_be
nvme.h: resync with nvme-cli
nvme: Add tertiary number to NVME_VS
nvme : Add sysfs entry for NVMe CMBs when appropriate
nvme: don't schedule multiple resets
nvme: Delete created IO queues on reset
nvme: Stop probing a removed device
badblocks: fix overlapping check for clearing
Import a few updates to nvme.h from nvme-cli. This mostly includes a few
new fields and error codes, but also a few renames that so far are only
used in user space. Also one field is moved from an array of two le64
values to one of 16 u8 values so that we can more easily access it.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
NVMe 1.2.1 specification adds a tertiary element to the version number.
This updates the macro and its callers to include the final number and
fixup a single place in nvmet where the version was generated manually.
Signed-off-by: Gabriel Krisman Bertazi <krisman@linux.vnet.ibm.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
Add a sysfs attribute that contains salient information about the NVMe
Controller Memory Buffer when one is present. For now, just display the
information about the CMB available from the control registers. We attach
the CMB attribute file to the existing nvme_ctrl sysfs group so it can
handle the sysfs teardown.
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Jay Freyensee <james_p_freyensee@linux.intel.com>
Signed-off-by: Stephen Bates <sbates@raithlin.com>
Acked-by Jon Derrick: <jonathan.derrick@intel.com>
Signed-off-by: Jens Axboe <axboe@fb.com>
The queue_work only fails if the work is pending, but not yet running. If
the work is running, the work item would get requeued, triggering a
double reset. If the first reset fails for any reason, the second
reset triggers:
WARN_ON(dev->ctrl.state == NVME_CTRL_RESETTING)
Hitting that schedules controller deletion for a second time, which
potentially takes a reference on the device that is being deleted.
If the reset occurs at the same time as a hot removal event, this causes
a double-free.
This patch has the reset helper function check if the work is busy
prior to queueing, and changes all places that schedule resets to use
this function. Since most users don't want to sync with that work, the
"flush_work" is moved to the only caller that wants to sync.
Signed-off-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Sagi Grimberg<sagi@grimberg.me>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@fb.com>
