When attaching a cached device (a.k.a backing device) to a cache
device, bch_sectors_dirty_init() is called to count dirty sectors
and stripes (see what bcache_dev_sectors_dirty_add() does) on the
cache device.

When bcache_dev_sectors_dirty_add() is called, set_bit(stripe,
d->full_dirty_stripes) or clear_bit(stripe, d->full_dirty_stripes)
operation will always be performed. In full_dirty_stripes, each 1bit
represents stripe_size (8192) sectors (512B), so 1bit=4MB (8192*512),
and each CPU cache line=64B=512bit=2048MB. When 20 threads process
a cached disk with 100G dirty data, a single thread processes about
23M at a time, and 20 threads total 460M. These full_dirty_stripes
bits corresponding to the 460M data is likely to fall in the same CPU
cache line. When one of these threads performs a set_bit or clear_bit
operation, the same CPU cache line of other threads will become invalid
and must read the full_dirty_stripes from the main memory again. Compared
with single thread, the time of a bcache_dev_sectors_dirty_add()
call is increased by about 50 times in our test (100G dirty data,
20 threads, bcache_dev_sectors_dirty_add() is called more than
20 million times).

This patch tries to test_bit before set_bit or clear_bit operation.
Therefore, a lot of force set and clear operations will be avoided,
and most of bcache_dev_sectors_dirty_add() calls will only read CPU
cache line.
Signed-off-by: Mingzhe Zou <mingzhe.zou@easystack.cn>
Signed-off-by: Coly Li <colyli@suse.de>

Use the helpers instead of open coding them.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220303111905.321089-11-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220303111905.321089-10-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220303111905.321089-9-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220303111905.321089-8-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220303111905.321089-7-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220303111905.321089-6-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use memcpy_from_bvec instead of open coding the logic.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220303111905.321089-5-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Use the proper helper instead of open coding the copy.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Link: https://lore.kernel.org/r/20220303111905.321089-4-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220303111905.321089-3-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Using local kmaps slightly reduces the chances to stray writes, and
the bvec interface cleans up the code a little bit.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Ira Weiny <ira.weiny@intel.com>
Acked-by: Max Filippov <jcmvbkbc@gmail.com>
Link: https://lore.kernel.org/r/20220303111905.321089-2-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

Pull NVMe updates from Christoph:

"nvme updates for Linux 5.18

 - add vectored-io support for user-passthrough (Kanchan Joshi)
 - add verbose error logging (Alan Adamson)
 - support buffered I/O on block devices in nvmet (Chaitanya Kulkarni)
 - central discovery controller support (Martin Belanger)
 - fix and extended the globally unique idenfier validation (me)
 - move away from the deprecated IDA APIs (Sagi Grimberg)
 - misc code cleanup (Keith Busch, Max Gurtovoy, Qinghua Jin,
   Chaitanya Kulkarni)"

* tag 'nvme-5.18-2022-03-03' of git://git.infradead.org/nvme: (27 commits)
  nvme: check that EUI/GUID/UUID are globally unique
  nvme: check for duplicate identifiers earlier
  nvme: fix the check for duplicate unique identifiers
  nvme: cleanup __nvme_check_ids
  nvme: remove nssa from struct nvme_ctrl
  nvme: explicitly set non-error for directives
  nvme: expose cntrltype and dctype through sysfs
  nvme: send uevent on connection up
  nvme: add vectored-io support for user-passthrough
  nvme: add verbose error logging
  nvme: add a helper to initialize connect_q
  nvme-rdma: add helpers for mapping/unmapping request
  nvmet-tcp: replace ida_simple[get|remove] with the simler ida_[alloc|free]
  nvmet-rdma: replace ida_simple[get|remove] with the simler ida_[alloc|free]
  nvmet-fc: replace ida_simple[get|remove] with the simler ida_[alloc|free]
  nvmet: replace ida_simple[get|remove] with the simler ida_[alloc|free]
  nvme-fc: replace ida_simple[get|remove] with the simler ida_[alloc|free]
  nvme: replace ida_simple[get|remove] with the simler ida_[alloc|free]
  nvmet: allow bdev in buffered_io mode
  nvmet: use i_size_read() to set size for file-ns
  ...

Add a check to verify that the unique identifiers are unique globally
in addition to the existing check that verifies that they are unique
inside a single subsystem.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

Lift the check for duplicate identifiers into nvme_init_ns_head, which
avoids pointless error unwinding in case they don't match, and also
matches where we check identifier validity for the multipath case.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

nvme_subsys_check_duplicate_ids should needs to return an error if any of
the identifiers matches, not just if all of them match.  But it does not
need to and should not look at the CSI value for this sanity check.

Rewrite the logic to be separate from nvme_ns_ids_equal and optimize it
by reducing duplicate checks for non-present identifiers.

Fixes: ed754e5d ("nvme: track shared namespaces")
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

Pass the actual nvme_ns_ids used for the comparison instead of the
ns_head that isn't needed and use a more descriptive function name.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>

The reported number of streams is not used outside the function that
gets it, so no need to stash it in the controller structure. Use a local
variable instead.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Stream directives is an optional feature. It is not an error if a
controller doesn't support as many as the kernel can optionally use.
Explicitly set the non-error return value on this condition with a
comment explaining why.

Note, the return value was already 0 in this condition, so the setting
is redundant. This patch should just silence bots that falsely believe
the condition contains an error omission.
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

TP8010 introduces the Discovery Controller Type attribute (dctype).
The dctype is returned in the response to the Identify command. This
patch exposes the dctype through the sysfs. Since the dctype depends on
the Controller Type (cntrltype), another attribute of the Identify
response, the patch also exposes the cntrltype as well. The dctype will
only be displayed for discovery controllers.

A note about the naming of this attribute:
Although TP8010 calls this attribute the Discovery Controller Type,
note that the dctype is now part of the response to the Identify
command for all controller types. I/O, Discovery, and Admin controllers
all share the same Identify response PDU structure. Non-discovery
controllers as well as pre-TP8010 discovery controllers will continue
to set this field to 0 (which has always been the default for reserved
bytes). Per TP8010, the value 0 now means "Discovery controller type is
not reported" instead of "Reserved". One could argue that this
definition is correct even for non-discovery controllers, and by
extension, exposing it in the sysfs for non-discovery controllers is
appropriate.
Signed-off-by: Martin Belanger <martin.belanger@dell.com>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: John Meneghini <jmeneghi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

When connectivity with a controller is lost, the driver will keep
trying to reconnect once every 10 sec. When connection is restored,
user-space apps need to be informed so that they can take proper
action. For example, TP8010 introduces the DIM PDU, which is used to
register with a discovery controller (DC). The DIM PDU is sent from
user-space.  The DIM PDU must be sent every time a connection is
established with a DC. Therefore, the kernel must tell user-space apps
when connection is restored so that registration can happen.

The uevent sent is a "change" uevent with environmental data
set to: "NVME_EVENT=connected".
Signed-off-by: Martin Belanger <martin.belanger@dell.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: John Meneghini <jmeneghi@redhat.com>
Reviewed-by: Hannes Reinecke <hare@suse.de>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Add a new NVME_IOCTL_IO64_CMD_VEC ioctl that works like the existing
NVME_IOCTL_IO64_CMD ioctl except that it takes and array of iovecs
and thus supports vectored I/O.

  - cmd.addr is base address of user iovec array
  - cmd.vec_cnt is count of iovec array elements

This patch does not include vectored-variant for admin-commands as most
of them are light on buffers and likely to have low invocation frequency.
Signed-off-by: Kanchan Joshi <joshi.k@samsung.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Improves logging of NVMe errors.  If NVME_VERBOSE_ERRORS is configured,
a verbose description of the error is logged, otherwise only status
codes/bits is logged.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
[kch]: fix several nits, cosmetics, and trim down code.
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Alan Adamson <alan.adamson@oracle.com>
Reviewed-by: Himanshu Madhani <himanshu.madhani@oracle.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Add and use helper to remove duplicate code for fabrics connect_q
initialization and error handling for all the transports.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Introduce nvme_rdma_dma_map_req/nvme_rdma_dma_unmap_req helper functions
to improve code readability and ease on the error flow.
Reviewed-by: Israel Rukshin <israelr@nvidia.com>
Signed-off-by: Max Gurtovoy <mgurtovoy@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ida_simple_[get|remove] are wrappers anyways.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ida_simple_[get|remove] are wrappers anyways.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ida_simple_[get|remove] are wrappers anyways.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ida_simple_[get|remove] are wrappers anyways.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ida_simple_[get|remove] are wrappers anyways.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

ida_simple_[get|remove] are wrappers anyways.

Also, use ida_alloc_min with the ns_ida as namespace
enumeration starts with 1.
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Allow block device to be configured in the buffered I/O mode by using
the file backend. In this way now we can use cache for the block
device namespace which shows significant performance improvement.

We update the block device ns enable function and return early when
buffered_io flag is set.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Instead of calling vfs_getattr() use i_size_read() to read the size of
file so we can read the size of not only file type but also block type
with one call. This is needed to implement buffered_io support for the
NVMeOF block device backend.

We also change return type of function nvmet_file_ns_revalidate() from
int to void, since this function does not return any meaning value.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Braces are not required for enum value NVME_SC_CONNECT_INVALID_PARAM
when used on the switch-case statement, remove the braces.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Remove zeroout memeset call & zeroout local variable cmd at the time
of declaration in nvmf_ref_read32() similar to what we have done in
nvmf_reg_read64(), nvmf_reg_write32(), nvmf_connect_admin_queue(), and
nvmf_connect_io_queue().
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Loop variable i will never have a negative value, so use
unsigned int type instaed of int.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Loop variable i will never have a negative value, so use
unsigned int type instaed of int.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

In function nvme_execute_rq() we don't use gendisk parameter at all.
Remove the unsed parameter and adjust the calls.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

It is not a good practice to have a semicolon at the end of the
function definition. Remove it from nvme_pr_type().
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Christoph Hellwig <hch@lst.de>

subsytem -> subsystem
Signed-off-by: Qinghua Jin <qhjin.dev@gmail.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>

Remove goto labels and use direct returns as error unwinding code only
needs to free t_page variable if we alloc_pages() call fails as having
two labels for one kfree() can be avoided easily.
Signed-off-by: Chaitanya Kulkarni <kch@nvidia.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Link: https://lore.kernel.org/r/20220222152852.26043-3-kch@nvidia.comSigned-off-by: Jens Axboe <axboe@kernel.dk>