We have this:

ERROR: "__aeabi_ldivmod" [drivers/block/nbd.ko] undefined!
ERROR: "__divdi3" [drivers/block/nbd.ko] undefined!
nbd.c:(.text+0x247c72): undefined reference to `__divdi3'

due to a recent commit, that did 64-bit division. Use the proper
divider function so that 32-bit compiles don't break.

Fixes: ef77b515 ("nbd: use loff_t for blocksize and nbd_set_size args")
Signed-off-by: NJens Axboe <axboe@fb.com>

If we have large devices (say like the 40t drive I was trying to test with) we
will end up overflowing the int arguments to nbd_set_size and not get the right
size for our device.  Fix this by using loff_t everywhere so I don't have to
think about this again.  Thanks,
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Fix bug https://bugzilla.kernel.org/show_bug.cgi?id=188531. In function
mtip_block_initialize(), variable rv takes the return value, and its
value should be negative on errors. rv is initialized as 0 and is not
reset when the call to ida_pre_get() fails. So 0 may be returned.
The return value 0 indicates that there is no error, which may be
inconsistent with the execution status. This patch fixes the bug by
explicitly assigning -ENOMEM to rv on the branch that ida_pre_get()
fails.
Signed-off-by: NPan Bian <bianpan2016@163.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

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: NChaitanya Kulkarni <chaitanya.kulkarni@hgst.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens 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: NChaitanya Kulkarni <chaitanya.kulkarni@hgst.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

Since targets are given a virtual target device, it is necessary to
translate all communication between targets and the backend device.
Implement the translation layer for get/set bad block table.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

On target-specific operations pass on nvm_tgt_dev instead of the generic
nvm device.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Target devices do not have access to the device driver operations.
Introduce a helper function that exposes the max. number of physical
sectors supported by the underlying device.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Avoid calling media manager and device-specific operations directly from
rrpc. Create helper functions on lightnvm's core instead.
Signed-off-by: NJavier González <javier@cnexlabs.com>

Made it work with null_blk as well.
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens 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: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens 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.

A part of this transformation is that targets manage their blocks
internally. This patch eliminates the nvm_block abstraction and moves
block management to the target logic. The rrpc target is transformed.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Since LUNs are managed internally on targets, the media manager has no
access to the free LUN lists. Thus, debug functions that show LUN
information on the device should not be implemented on the media
manager, but rather on the target in itself.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Since LUNs are managed internally on the target, there is no need for
the media manager to implement a get_lun operation.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens 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: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

LUNs are exclusively owned by targets implementing a block device FTL.
Doing this reservation requires at the moment a 2-way callback gennvm
<-> target. The reason behind this is that LUNs were not assumed to
always be exclusively owned by targets. However, this design decision
goes against I/O determinism QoS (two targets would mix I/O on the same
parallel unit in the device).

This patch makes LUN reservation as part of the target creation on the
media manager. This makes that LUNs are always exclusively owned by the
target instantiated on top of them. LUN stripping and/or sharing should
be implemented on the target itself or the layers on top.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

The gen_lun abstraction in the generic media manager was conceived on
the assumption that a single target would instantiated on top of it.
This has complicated target design to implement multi-instances. Remove
this abstraction and move its logic to nvm_lun, which manages physical
lun geometry and operations.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

There is a constant to refer to free blocks. Use it when marking bad
blocks instead of using a constant value
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Before vectored I/Os were supported on rrpc, the physical address was
stored as part of the nvm_rqd request. This variable become obsolete
when the ppa_list was introduced. Cleanup this variable.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Targets are assumed to used the same generic ppa format, where the
address is partitioned on ch:lun:block:pg:pl:sec. Thus, make the
function in charge of transforming the ppa address from a linear format
to the generic one available to all targets.

This function will be needed by the media manager in order to do target
mapping translations when targets are divided on different physical
partitions.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

LightNVM used to be managed and configured through sysfs. Since the
introduction of management ioctls this interface is redundant and
outdated. Get rid of it.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

rrpc cannot handle bios of size > 256kb due to NVMe using a 64 bit
bitmap to signal I/O completion. If a larger bio comes, split it
explicitly.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Bad blocks should be managed by block owners. This would be either
targets for data blocks or sysblk for system blocks.

In order to support this, export two functions: One to mark a block as
an specific type (e.g., bad block) and another to update the bad block
table on the device.

Move bad block management to rrpc.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Device blocks should be marked by the device and considered as bad
blocks by the media manager. Thus, do not make assumptions on which
blocks are going to be used by the device. In doing so we might lose
valid blocks from the free list.
Signed-off-by: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens 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: NJavier González <javier@cnexlabs.com>
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens 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: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens 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: d49187e9 "nvme: introduce struct nvme_request"
Signed-off-by: NMatias Bjørling <m@bjorling.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Multiple paths don't set it properly, ensure that we do.

Fixes: 9561a7ad ("nbd: add multi-connection support")
Signed-off-by: NJens Axboe <axboe@fb.com>

NBD can become contended on its single connection.  We have to serialize all
writes and we can only process one read response at a time.  Fix this by
allowing userspace to provide multiple connections to a single nbd device.  This
coupled with block-mq drastically increases performance in multi-process cases.
Thanks,
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Instead we use standard iterator way to do that.
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

When the bio is full, bio_add_pc_page() will return zero,
so use this information tell when the bio is full.

Also replace access to .bi_vcnt for pr_debug() with bio_segments().
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Reviewed-by: NSagi Grimberg <sagi@grimberg.me>
Signed-off-by: NJens Axboe <axboe@fb.com>

Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

For a non-cloned bio, bio_add_page() only returns failure when
the io vec table is full, but in that case, bio->bi_vcnt can't
be zero at all.

So remove the impossible failure handling.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NLars Ellenberg <lars.ellenberg@linbit.com>
Signed-off-by: NMing Lei <tom.leiming@gmail.com>
Signed-off-by: NJens 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: NMing Lei <tom.leiming@gmail.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>

Fixed up the new O_DIRECT cases.
Signed-off-by: NJens Axboe <axboe@fb.com>

This driver is both orphaned, and not really useful anymore. Mark
it as such, and remove it in a future kernel after a release or
two.
Signed-off-by: NJens Axboe <axboe@fb.com>

Drop duplicate header scatterlist.h from skd_main.c.
Signed-off-by: NGeliang Tang <geliangtang@gmail.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

For writes, we can get a completion in while we're still iterating
the request and bio chain. If that happens, we're reading freed
memory and we can crash.

Break out after the last segment and avoid having the iterator
read freed memory.
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

If CONFIG_NVM is disabled, loading null_block module with use_lightnvm=1
fails. But there are no messages and documents related to the failure.

Add the appropriate error message.
Signed-off-by: NYasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>

Massaged the text a bit.
Signed-off-by: NJens 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: NOmar Sandoval <osandov@fb.com>
Signed-off-by: NJens 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: NOmar Sandoval <osandov@fb.com>
Reviewed-by: NKeith Busch <keith.busch@intel.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

->queue_rq() should return one of the BLK_MQ_RQ_QUEUE_* constants, not
an errno.

f4aa4c7b ("block: loop: convert to per-device workqueue")
Signed-off-by: NOmar Sandoval <osandov@fb.com>
Cc: stable@vger.kernel.org
Signed-off-by: NJens Axboe <axboe@fb.com>