xen-blkfron is the last users using rq->errros for passing back error to
blk-mq, and I'd like to get rid of that.  In the longer run the driver
should be moving more of the completion processing into .complete, but
this is the minimal change to move forward for now.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NRoger Pau Monné <roger.pau@citrix.com>
Reviewed-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Instead of using req->errors, which will go away.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

Add a nbd-specific field instead.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

We'll get all proper errors reported through ->end_io and ->errors will
go away soon.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

dm never uses rq->errors, so there is no need to pass an error argument
to blk_mq_complete_request.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

In thruth I've just audited which blk-mq drivers don't currently have a
complete callback, but I think this change is at least borderline useful.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

This passes on the scsi_cmnd result field to users of passthrough
requests.  Currently we abuse req->errors for this purpose, but that
field will go away in its current form.

Note that the old IDE code abuses the errors field in very creative
ways and stores all kinds of different values in it.  I didn't dare
to touch this magic, so the abuses are brought forward 1:1.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Remove passing req->errors (which at that point is always 0) to
blk_mq_complete_request, and rely on the virtio status code for the
serial number passthrough request.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Currently it's used by the lighnvm passthrough ioctl, but we'd like to make
it private in preparation of block layer specific error code.  Lighnvm already
returns the real NVMe status anyway, so I think we can just limit it to
returning -EIO for any status set.

This will need a careful audit from the lightnvm folks, though.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

We want our own clearly defined error field for NVMe passthrough commands,
and the request errors field is going away in its current form.

Just store the status and result field in the nvme_request field from
hardirq completion context (using a new helper) and then generate a
Linux errno for the block layer only when we actually need it.

Because we can't overload the status value with a negative error code
for cancelled command we now have a flags filed in struct nvme_request
that contains a bit for this condition.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

nvme_complete_async_event expects the little endian status code
including the phase bit, and a new completion handler I plan to
introduce will do so as well.

Change the status variable into the little endian format with the
phase bit used in the NVMe CQE to fix / enable this.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

The function only returns -EIO if rq->errors is non-zero, which is not
very useful and lets a large number of callers ignore the return value.

Just let the callers figure out their error themselves.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

The driver never sets req->errors, so blk_execute_rq will always return 0.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NBart Van Assche <Bart.VanAssche@sandisk.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

Drop 'parent' argument of bdi_register() and bdi_register_va().  It is
always NULL.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@fb.com>

Now that all bdi structures filesystems use are properly refcounted, we
can remove the SB_I_DYNBDI flag.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@fb.com>

MTD already allocates backing_dev_info dynamically. Convert it to use
generic infrastructure for this including proper refcounting. We drop
mtd->backing_dev_info as its only use was to pass mtd_bdi pointer from
one file into another and if we wanted to keep that in a clean way, we'd
have to make mtd hold and drop bdi reference as needed which seems
pointless for passing one global pointer...

CC: David Woodhouse <dwmw2@infradead.org>
CC: Brian Norris <computersforpeace@gmail.com>
CC: linux-mtd@lists.infradead.org
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@fb.com>

Allocate struct backing_dev_info separately instead of embedding it
inside superblock. This unifies handling of bdi among users.

CC: Oleg Drokin <oleg.drokin@intel.com>
CC: Andreas Dilger <andreas.dilger@intel.com>
CC: James Simmons <jsimmons@infradead.org>
CC: lustre-devel@lists.lustre.org
Reviewed-by: NAndreas Dilger <andreas.dilger@intel.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@fb.com>

On an error path in NVM_DEV_CREATE ioctl blk_put_queue is being called
twice: one via blk_cleanup_queue and another via put_disk.  Straight fix
seems to remove queue pointer so that disk_release never ends up caling
blk_put_queue again.

  [  391.808827] WARNING: CPU: 1 PID: 1250 at lib/refcount.c:128 refcount_sub_and_test+0x70/0x80
  [  391.808830] refcount_t: underflow; use-after-free.
  [ 391.808832] Modules linked in: nf_conntrack_netbios_ns............
  [  391.809052] CPU: 1 PID: 1250 Comm: nvme Not tainted.........
  [  391.809057] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
             BIOS rel-1.7.5-0-ge51488c-20140602_164612-nilsson.home.kraxel.org 04/01/2014
  [  391.809060] Call Trace:
  [  391.809079]  dump_stack+0x63/0x86
  [  391.809094]  __warn+0xcb/0xf0
  [  391.809103]  warn_slowpath_fmt+0x5f/0x80
  [  391.809118]  refcount_sub_and_test+0x70/0x80
  [  391.809125]  refcount_dec_and_test+0x11/0x20
  [  391.809136]  kobject_put+0x1f/0x60
  [  391.809149]  blk_put_queue+0x15/0x20
  [  391.809159]  disk_release+0xae/0xf0
  [  391.809172]  device_release+0x32/0x90
  [  391.809184]  kobject_release+0x6a/0x170
  [  391.809196]  kobject_put+0x2f/0x60
  [  391.809206]  put_disk+0x17/0x20
  [  391.809219]  nvm_ioctl_dev_create.isra.16+0x897/0xa30
  [  391.809236]  nvm_ctl_ioctl+0x23c/0x4c0
  [  391.809248]  do_vfs_ioctl+0xa3/0x5f0
  [  391.809258]  SyS_ioctl+0x79/0x90
  [  391.809271]  entry_SYSCALL_64_fastpath+0x1a/0xa9
  [  391.809280] RIP: 0033:0x7f5d3ef363c7
  [  391.809286] RSP: 002b:00007ffc72ed8d78 EFLAGS: 00000206 ORIG_RAX: 0000000000000010
  [  391.809296] RAX: ffffffffffffffda RBX: 00007ffc72edb552 RCX: 00007f5d3ef363c7
  [  391.809301] RDX: 00007ffc72ed8d90 RSI: 0000000040804c22 RDI: 0000000000000003
  [  391.809306] RBP: 0000000000000001 R08: 0000000000000020 R09: 0000000000000001
  [  391.809311] R10: 000000000000053f R11: 0000000000000206 R12: 0000000000000000
  [  391.809316] R13: 0000000000000000 R14: 00007ffc72edb58d R15: 00007ffc72edb581
Signed-off-by: NRakesh Pandit <rakesh@tuxera.com>
Reviewed-by: NMatias Bjørling <matias@cnexlabs.com>
Fixes: 7d1ef2f4 "lightnvm: fix cleanup order of disk on init error"
Signed-off-by: NJens Axboe <axboe@fb.com>

This patch changes the behavior of the lightnvm driver as follows:
* REQ_FAILFAST_MASK is set for read-ahead requests.
* If no I/O priority has been set in the bio, the I/O priority is
  copied from the I/O context.
* The rq_disk member is initialized if bio->bi_bdev != NULL.
* The bio sector offset is copied into req->__sector instead of
  retaining the value -1 set by blk_mq_alloc_request().
* req->errors is initialized to zero.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: Matias Bjørling <m@bjorling.me>
Cc: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

This patch changes the behavior of the null_blk driver for the
LightNVM mode as follows:
* REQ_FAILFAST_MASK is set for read-ahead requests.
* If no I/O priority has been set in the bio, the I/O priority is
  copied from the I/O context.
* The rq_disk member is initialized if bio->bi_bdev != NULL.
* req->errors is initialized to zero.
Signed-off-by: NBart Van Assche <bart.vanassche@sandisk.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Cc: Matias Bjørling <m@bjorling.me>
Cc: Adam Manzanares <adam.manzanares@wdc.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

The driver uses both u64 and sector_t to refer to offsets, and assigns between the
two. This causes one harmless warning when sector_t is 32-bit:

drivers/lightnvm/pblk-rb.c: In function 'pblk_rb_write_entry_gc':
include/linux/lightnvm.h:215:20: error: large integer implicitly truncated to unsigned type [-Werror=overflow]
drivers/lightnvm/pblk-rb.c:324:22: note: in expansion of macro 'ADDR_EMPTY'

As the driver is already doing this inconsistently, changing the type
won't make it worse and is an easy way to avoid the warning.

Fixes: a4bd217b ("lightnvm: physical block device (pblk) target")
Signed-off-by: NArnd Bergmann <arnd@arndb.de>
Signed-off-by: NJens Axboe <axboe@fb.com>

This was just a proof of concept user for the SCSI OSD library, and
never had any real users.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Acked-by: NBoaz Harrosh <ooo@electrozaur.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

NBD doesn't care about limiting the segment size, let the user push the
largest bio's they want.  This allows us to control the request size
solely through max_sectors_kb.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Reviewed-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

When a blkfront device is resized from dom0, emit a KOBJ_CHANGE uevent to
notify the guest about the change. This allows for custom udev rules, such
as automatically resizing a filesystem, when an event occurs.

With this patch you get these udev

KERNEL[577.206230] change   /devices/vbd-51728/block/xvdb (block)
UDEV  [577.226218] change   /devices/vbd-51728/block/xvdb (block)
Signed-off-by: NMarc Olson <marcolso@amazon.com>
Signed-off-by: NKonrad Rzeszutek Wilk <konrad.wilk@oracle.com>

For ease of management it would be nice for users to specify that the
device node for a nbd device is destroyed once it is disconnected and
there are no more users.  Add a client flag and enable this operation to
happen.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

In order to support deleting the device on disconnect we need to
refcount the actual nbd_device struct.  So add the refcounting framework
and change how we free the normal devices at rmmod time so we can catch
reference leaks.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Allow users to query the status of existing nbd devices.  Right now this
only returns whether or not the device is connected, but could be
extended in the future to include more information.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Sometimes we like to upgrade our server without making all of our
clients freak out and reconnect.  This patch provides a way to specify a
dead connection timeout to allow us to pause all requests and wait for
new connections to be opened.  With this in place I can take down the
nbd server for less than the dead connection timeout time and bring it
back up and everything resumes gracefully.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

When running a disconnect torture test I noticed that sometimes we would
crash with a negative ref count on our queue.  This was because we were
ending the same request twice.  Turns out we were racing with
NBD_CLEAR_SOCK clearing the requests as well as the teardown of the
device clearing the requests.  So instead make the ioctl only shutdown
the sockets and make it so that we only ever run nbd_clear_que from the
device teardown.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Provide a mechanism to notify userspace that there's been a link problem
on a NBD device.  This will allow userspace to re-establish a connection
and provide the new socket to the device without disrupting the device.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

We want to be able to reconnect dead connections to existing block
devices, so add a reconfigure netlink command.  We will also allow users
to change their timeout on the fly, but everything else will require a
disconnect and reconnect.  You won't be able to add more connections
either, simply replace dead connections with new more lively
connections.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

The existing ioctl interface for configuring NBD devices is a bit
cumbersome and hard to extend.  The other problem is we leave a
userspace app sitting in it's syscall until the device disconnects,
which is less than ideal.

This patch introduces a netlink interface for adding and disconnecting
nbd devices.  This has the benefits of being easily extendable without
breaking older userspace applications, and allows us to configure a nbd
device without leaving a userspace app sitting waiting for the device to
disconnect.

With this interface we also gain the ability to configure more devices
than are preallocated at insmod time.  We also have gained the ability
to not specify a particular device and be provided one for us so that
userspace doesn't need to find a free device to configure.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

In preparation for the upcoming netlink interface we need to not rely on
already having the bdev for the NBD device we are doing operations on.
Instead of passing the bdev around, just use it in places where we know
we already have the bdev.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

In order to properly refcount the various aspects of a NBD device we
need to separate out the configuration elements of the nbd device.  The
configuration of a NBD device has a different lifetime from the actual
device, so it doesn't make sense to bundle these two concepts.  Add a
config_refs to keep track of the configuration structure, that way we
can be sure that we never access it when we've torn down the device.
Add a new nbd_config structure to hold all of the transient
configuration information.  Finally create this when we open the device
so that it is in place when we start to configure the device.  This has
a nice side-effect of fixing a long standing problem where you could end
up with a half-configured nbd device that needed to be "disconnected" in
order to be usable again.  Now once we close our device the
configuration will be discarded.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

Currently if we have multiple connections and one of them goes down we will tear
down the whole device.  However there's no reason we need to do this as we
could have other connections that are working fine.  Deal with this by keeping
track of the state of the different connections, and if we lose one we mark it
as dead and send all IO destined for that socket to one of the other healthy
sockets.  Any outstanding requests that were on the dead socket will timeout and
be re-submitted properly.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

When adding a new socket we look it up and then try to add it to our
configuration.  If any of those steps fail we need to make sure we put
the socket so we don't leak them.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

There were a bunch of places in pblk_lines_init() where we didn't set an
error code.  And in pblk_writer_init() we accidentally return 1 instead
of a correct error code, which would result in a Oops later.

Fixes: 11a5d6fdf919 ("lightnvm: physical block device (pblk) target")
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NMatias Bjørling <matias@cnexlabs.com>
Signed-off-by: NJens Axboe <axboe@fb.com>

WARN_ON() takes a condition, not an error message.  I slightly tweaked
some conditions so hopefully it's more clear.
Signed-off-by: NDan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: NMatias Bjørling <matias@cnexlabs.com>
Signed-off-by: NJens Axboe <axboe@fb.com>