If the device is setup with ioctl we can resize the device after the
initial setup, but if the device is setup with netlink we cannot use the
resize related ioctls and there is no netlink reconfigure size ATTR
handling code.

This patch adds netlink reconfigure resize support to match the ioctl
interface.
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NMike Christie <mchristi@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This will allow the blksize to be set zero and then use 1024 as
default.
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NXiubo Li <xiubli@redhat.com>
[fix to use goto out instead of return in genl_connect]
Signed-off-by: NMike Christie <mchristi@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Based on 1 normalized pattern(s):

  this file is released under gplv2 or later

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-or-later

has been chosen to replace the boilerplate/reference in 1 file(s).
Signed-off-by: NThomas Gleixner <tglx@linutronix.de>
Reviewed-by: NRichard Fontana <rfontana@redhat.com>
Reviewed-by: NKate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: NAllison Randal <allison@lohutok.net>
Reviewed-by: NArmijn Hemel <armijn@tjaldur.nl>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190527063114.295960793@linutronix.de
Link: https://lkml.kernel.org/r/20190524100843.018830140@linutronix.deSigned-off-by: NGreg Kroah-Hartman <gregkh@linuxfoundation.org>

Add options to strictly validate messages and dump messages,
sometimes perhaps validating dump messages non-strictly may
be required, so add an option for that as well.

Since none of this can really be applied to existing commands,
set the options everwhere using the following spatch:

    @@
    identifier ops;
    expression X;
    @@
    struct genl_ops ops[] = {
    ...,
     {
            .cmd = X,
    +       .validate = GENL_DONT_VALIDATE_STRICT | GENL_DONT_VALIDATE_DUMP,
            ...
     },
    ...
    };

For new commands one should just not copy the .validate 'opt-out'
flags and thus get strict validation.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

We currently have two levels of strict validation:

 1) liberal (default)
     - undefined (type >= max) & NLA_UNSPEC attributes accepted
     - attribute length >= expected accepted
     - garbage at end of message accepted
 2) strict (opt-in)
     - NLA_UNSPEC attributes accepted
     - attribute length >= expected accepted

Split out parsing strictness into four different options:
 * TRAILING     - check that there's no trailing data after parsing
                  attributes (in message or nested)
 * MAXTYPE      - reject attrs > max known type
 * UNSPEC       - reject attributes with NLA_UNSPEC policy entries
 * STRICT_ATTRS - strictly validate attribute size

The default for future things should be *everything*.
The current *_strict() is a combination of TRAILING and MAXTYPE,
and is renamed to _deprecated_strict().
The current regular parsing has none of this, and is renamed to
*_parse_deprecated().

Additionally it allows us to selectively set one of the new flags
even on old policies. Notably, the UNSPEC flag could be useful in
this case, since it can be arranged (by filling in the policy) to
not be an incompatible userspace ABI change, but would then going
forward prevent forgetting attribute entries. Similar can apply
to the POLICY flag.

We end up with the following renames:
 * nla_parse           -> nla_parse_deprecated
 * nla_parse_strict    -> nla_parse_deprecated_strict
 * nlmsg_parse         -> nlmsg_parse_deprecated
 * nlmsg_parse_strict  -> nlmsg_parse_deprecated_strict
 * nla_parse_nested    -> nla_parse_nested_deprecated
 * nla_validate_nested -> nla_validate_nested_deprecated

Using spatch, of course:
    @@
    expression TB, MAX, HEAD, LEN, POL, EXT;
    @@
    -nla_parse(TB, MAX, HEAD, LEN, POL, EXT)
    +nla_parse_deprecated(TB, MAX, HEAD, LEN, POL, EXT)

    @@
    expression NLH, HDRLEN, TB, MAX, POL, EXT;
    @@
    -nlmsg_parse(NLH, HDRLEN, TB, MAX, POL, EXT)
    +nlmsg_parse_deprecated(NLH, HDRLEN, TB, MAX, POL, EXT)

    @@
    expression NLH, HDRLEN, TB, MAX, POL, EXT;
    @@
    -nlmsg_parse_strict(NLH, HDRLEN, TB, MAX, POL, EXT)
    +nlmsg_parse_deprecated_strict(NLH, HDRLEN, TB, MAX, POL, EXT)

    @@
    expression TB, MAX, NLA, POL, EXT;
    @@
    -nla_parse_nested(TB, MAX, NLA, POL, EXT)
    +nla_parse_nested_deprecated(TB, MAX, NLA, POL, EXT)

    @@
    expression START, MAX, POL, EXT;
    @@
    -nla_validate_nested(START, MAX, POL, EXT)
    +nla_validate_nested_deprecated(START, MAX, POL, EXT)

    @@
    expression NLH, HDRLEN, MAX, POL, EXT;
    @@
    -nlmsg_validate(NLH, HDRLEN, MAX, POL, EXT)
    +nlmsg_validate_deprecated(NLH, HDRLEN, MAX, POL, EXT)

For this patch, don't actually add the strict, non-renamed versions
yet so that it breaks compile if I get it wrong.

Also, while at it, make nla_validate and nla_parse go down to a
common __nla_validate_parse() function to avoid code duplication.

Ultimately, this allows us to have very strict validation for every
new caller of nla_parse()/nlmsg_parse() etc as re-introduced in the
next patch, while existing things will continue to work as is.

In effect then, this adds fully strict validation for any new command.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

Even if the NLA_F_NESTED flag was introduced more than 11 years ago, most
netlink based interfaces (including recently added ones) are still not
setting it in kernel generated messages. Without the flag, message parsers
not aware of attribute semantics (e.g. wireshark dissector or libmnl's
mnl_nlmsg_fprintf()) cannot recognize nested attributes and won't display
the structure of their contents.

Unfortunately we cannot just add the flag everywhere as there may be
userspace applications which check nlattr::nla_type directly rather than
through a helper masking out the flags. Therefore the patch renames
nla_nest_start() to nla_nest_start_noflag() and introduces nla_nest_start()
as a wrapper adding NLA_F_NESTED. The calls which add NLA_F_NESTED manually
are rewritten to use nla_nest_start().

Except for changes in include/net/netlink.h, the patch was generated using
this semantic patch:

@@ expression E1, E2; @@
-nla_nest_start(E1, E2)
+nla_nest_start_noflag(E1, E2)

@@ expression E1, E2; @@
-nla_nest_start_noflag(E1, E2 | NLA_F_NESTED)
+nla_nest_start(E1, E2)
Signed-off-by: NMichal Kubecek <mkubecek@suse.cz>
Acked-by: NJiri Pirko <jiri@mellanox.com>
Acked-by: NDavid Ahern <dsahern@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

This adds four tracepoints to nbd, enabling separate tracing of payload
and header sending/receipt.

In the send path for headers that have already been sent, we also
explicitly initialize the handle so it can be referenced by the later
tracepoint.
Signed-off-by: NAndrew Hall <hall@fb.com>
Signed-off-by: NMatt Mullins <mmullins@fb.com>
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

This adds a tracepoint that can both observe the nbd request being sent
to the server, as well as modify that request , e.g., setting a flag in
the request that will cause the server to collect detailed tracing data.

The struct request * being handled is included to permit correlation
with the block tracepoints.
Signed-off-by: NMatt Mullins <mmullins@fb.com>
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NAlexei Starovoitov <ast@kernel.org>

Since maxattr is common, the policy can't really differ sanely,
so make it common as well.

The only user that did in fact manage to make a non-common policy
is taskstats, which has to be really careful about it (since it's
still using a common maxattr!). This is no longer supported, but
we can fake it using pre_doit.

This reduces the size of e.g. nl80211.o (which has lots of commands):

   text	   data	    bss	    dec	    hex	filename
 398745	  14323	   2240	 415308	  6564c	net/wireless/nl80211.o (before)
 397913	  14331	   2240	 414484	  65314	net/wireless/nl80211.o (after)
--------------------------------
   -832      +8       0    -824

Which is obviously just 8 bytes for each command, and an added 8
bytes for the new policy pointer. I'm not sure why the ops list is
counted as .text though.

Most of the code transformations were done using the following spatch:
    @ops@
    identifier OPS;
    expression POLICY;
    @@
    struct genl_ops OPS[] = {
    ...,
     {
    -	.policy = POLICY,
     },
    ...
    };

    @@
    identifier ops.OPS;
    expression ops.POLICY;
    identifier fam;
    expression M;
    @@
    struct genl_family fam = {
            .ops = OPS,
            .maxattr = M,
    +       .policy = POLICY,
            ...
    };

This also gets rid of devlink_nl_cmd_region_read_dumpit() accessing
the cb->data as ops, which we want to change in a later genl patch.
Signed-off-by: NJohannes Berg <johannes.berg@intel.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

genlmsg_reply can fail, so propagate its return code
Signed-off-by: NLi RongQing <lirongqing@baidu.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

QUEUE_FLAG_NO_SG_MERGE has been killed, so kill BLK_MQ_F_SG_MERGE too.
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NOmar Sandoval <osandov@fb.com>
Signed-off-by: NMing Lei <ming.lei@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

NBD can update block device block size implicitely through
bd_set_size(). Make it explicitely set blocksize with set_blocksize() as
this behavior of bd_set_size() is going away.

CC: Josef Bacik <jbacik@fb.com>
Signed-off-by: NJan Kara <jack@suse.cz>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We have this functionality in sbitmap, but we don't export it in
blk-mq for users of the tags busy iteration. This can be useful
for stopping the iteration, if the caller doesn't need to find
more requests.
Reviewed-by: NMike Snitzer <snitzer@redhat.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

In the iov_iter struct, separate the iterator type from the iterator
direction and use accessor functions to access them in most places.

Convert a bunch of places to use switch-statements to access them rather
then chains of bitwise-AND statements.  This makes it easier to add further
iterator types.  Also, this can be more efficient as to implement a switch
of small contiguous integers, the compiler can use ~50% fewer compare
instructions than it has to use bitwise-and instructions.

Further, cease passing the iterator type into the iterator setup function.
The iterator function can set that itself.  Only the direction is required.
Signed-off-by: NDavid Howells <dhowells@redhat.com>

syzbot reports a divide-by-zero off the NBD_SET_BLKSIZE ioctl.
We need proper validation of the input here. Not just if it's
zero, but also if the value is a power-of-2 and in a valid
range. Add that.

Cc: stable@vger.kernel.org
Reported-by: Nsyzbot <syzbot+25dbecbec1e62c6b0dd4@syzkaller.appspotmail.com>
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The netlink policy should be const like other drivers.
Signed-off-by: NStephen Hemminger <stephen@networkplumber.org>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

If the server or network is misbehaving and we get an unexpected reply
we can sometimes miss the request not being started and wait on a
request and never get a response, or even double complete the same
request.  Fix this by replacing the send_complete completion with just a
per command lock.  Add a per command cookie as well so that we can know
if we're getting a double completion for a previous event.  Also check
to make sure we dont have REQUEUED set as that means we raced with the
timeout handler and need to just let the retry occur.
Signed-off-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We can race with the snd timeout and the per-request timeout and end up
requeuing the same request twice.  We can't use the send_complete
completion to tell if everything is ok because we hold the tx_lock
during send, so the timeout stuff will block waiting to mark the socket
dead, and we could be marked complete and still requeue.  Instead add a
flag to the socket so we know whether we've been requeued yet.
Signed-off-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If NBD_DISCONNECT_ON_CLOSE is set on a device, then the driver will
issue a disconnect from nbd_release if the device has no remaining
bdev->bd_openers.

Fix ret val so reconfigure with only setting the flag succeeds.
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NDoron Roberts-Kedes <doronrk@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Technically we should be able to get away with 0 as the
discard_alignment, but there's no way currently for the protocol to
indicate different alignments, and in real life most disks have
discard_alignment == discard_granularity.  Just set our alignment to our
blocksize to make sure discards will actually work properly with 4k
drives.
Signed-off-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Existing dev_dbg messages sometimes identify request using request
pointer, sometimes using nbd_cmd pointer. This makes it hard to
follow request flow. Consistently use request pointer instead.
Reviewed-by: NJosef Bacik <jbacik@toxicpanda.com>
Signed-off-by: NKevin Vigor <kvigor@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We already check for started commands in all callbacks, but we should
also protect against already completed commands.  Do this by taking
the checks to common code.
Acked-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

When a userspace client requests a NBD device be disconnected, the
DISCONNECT_REQUESTED flag is set. While this flag is set, the driver
will not inform userspace when a connection is closed.

Unfortunately the flag was never cleared, so once a disconnect was
requested the driver would thereafter never tell userspace about a
closed connection. Thus when connections failed due to timeout, no
attempt to reconnect was made and eventually the device would fail.

Fix by clearing the DISCONNECT_REQUESTED flag (and setting the
DISCONNECTED flag) once all connections are closed.
Reviewed-by: NJosef Bacik <josef@toxicpanda.com>
Signed-off-by: NKevin Vigor <kvigor@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

By completing the request entirely in the driver we can remove the
BLK_EH_HANDLED return value and thus the split responsibility between the
driver and the block layer that has been causing trouble.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

The BLK_EH_NOT_HANDLED implies nothing happen, but very often that
is not what is happening - instead the driver already completed the
command.  Fix the symbolic name to reflect that a little better.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NHannes Reinecke <hare@suse.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Convert the S_<FOO> symbolic permissions to their octal equivalents as
using octal and not symbolic permissions is preferred by many as more
readable.

see: https://lkml.org/lkml/2016/8/2/1945

Done with automated conversion via:
$ ./scripts/checkpatch.pl -f --types=SYMBOLIC_PERMS --fix-inplace <files...>

Miscellanea:

o Wrapped modified multi-line calls to a single line where appropriate
o Realign modified multi-line calls to open parenthesis
Signed-off-by: NJoe Perches <joe@perches.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

For some reason we had discard granularity set to 512 always even when
discards were disabled.  Fix this by having the default be 0, and then
if we turn it on set the discard granularity to the blocksize.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

Add WQ_UNBOUND to the knbd-recv workqueue so we're not bound
to a single CPU that is selected at device creation time.
Signed-off-by: NDan Melnic <dmm@fb.com>
Reviewed-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We need to make sure we don't just set the size of the bdev to 0 while
it's being used by a file system.  We have the appropriate check in
nbd_bdev_reset, simply use that helper instead.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

bd_invalidated is kind of a pain wrt partitions as it really only
triggers the partition rescan if it is set after bd_ops->open() runs, so
setting it when we reset the device isn't useful.  We also sporadically
would still have partitions left over in some disconnect cases, so fix
this by always setting bd_invalidated on open if there's no
configuration or if we've had a disconnect action happen, that way the
partition table gets invalidated and rescanned properly.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This is what the ioctl based nbd disconnect does as well.  Without this
the device will just sit there and wait for the connection to go away
(or IO to occur) before the device gets torn down.  Instead clear
everything up on our end so the configuration goes away as quickly as
possible.
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

When we stopped relying on the bdev everywhere I broke updating the
block device size on the fly, which ceph relies on.  We can't just do
set_capacity, we also have to do bd_set_size so things like parted will
notice the device size change.

Fixes: 29eaadc0 ("nbd: stop using the bdev everywhere")
cc: stable@vger.kernel.org
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

I messed up changing the size of an NBD device while it was connected by
not actually updating the device or doing the uevent.  Fix this by
updating everything if we're connected and we change the size.

cc: stable@vger.kernel.org
Fixes: 639812a1 ("nbd: don't set the device size until we're connected")
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This fixes a use after free bug, we shouldn't be doing disk->queue right
after we do del_gendisk(disk).  Save the queue and do the cleanup after
the del_gendisk.

Fixes: c6a4759e ("nbd: add device refcounting")
cc: stable@vger.kernel.org
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

This patch has been generated as follows:

for verb in set_unlocked clear_unlocked set clear; do
  replace-in-files queue_flag_${verb} blk_queue_flag_${verb%_unlocked} \
    $(git grep -lw queue_flag_${verb} drivers block/bsg*)
done

Except for protecting all queue flag changes with the queue lock
this patch does not change any functionality.

Cc: Mike Snitzer <snitzer@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Hannes Reinecke <hare@suse.de>
Cc: Ming Lei <ming.lei@redhat.com>
Signed-off-by: NBart Van Assche <bart.vanassche@wdc.com>
Reviewed-by: NMartin K. Petersen <martin.petersen@oracle.com>
Reviewed-by: NJohannes Thumshirn <jthumshirn@suse.de>
Acked-by: NMartin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

It seems that the proper value to return in this particular case is the
one contained into variable new_index instead of ret.

Addresses-Coverity-ID: 1465148 ("Copy-paste error")
Fixes: e46c7287 ("nbd: add a basic netlink interface")
Reviewed-by: NOmar Sandoval <osandov@fb.com>
Signed-off-by: NGustavo A. R. Silva <gustavo@embeddedor.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

We can end up sleeping for a while waiting for the dead timeout, which
means we could get the per request timer to fire.  We did handle this
case, but if the dead timeout happened right after we submitted we'd
either tear down the connection or possibly requeue as we're handling an
error and race with the endio which can lead to panics and other
hilarity.

Fixes: 560bc4b3 ("nbd: handle dead connections")
Cc: stable@vger.kernel.org
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If we have a pending signal or the user kills their application then
it'll bring down the whole device, which is less than awesome.  Instead
wait uninterruptible for the dead timeout so we're sure we gave it our
best shot.

Fixes: 560bc4b3 ("nbd: handle dead connections")
Cc: stable@vger.kernel.org
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

If you do not set sk_sndtimeo you will get -ERESTARTSYS if there is a
pending signal when you enter sendmsg, which we handle properly.
However if you set a timeout for your commands we'll set sk_sndtimeo to
that timeout, which means that sendmsg will start returning -EINTR
instead of -ERESTARTSYS.  Fix this by checking either cases and doing
the correct thing.

Cc: stable@vger.kernel.org
Fixes: dc88e34d ("nbd: set sk->sk_sndtimeo for our sockets")
Reported-and-tested-by: NDaniel Xu <dlxu@fb.com>
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>

A user reported a regression with using the normal ioctl interface on
newer kernels.  This happens because I was setting the device size
before the device was actually connected, which caused us to error out
and close everything down.  This didn't happen on netlink because we
hold the device lock the whole time we're setting things up, but we
don't do that for the ioctl path.  This fixes the problem.

Cc: stable@vger.kernel.org
Fixes: 29eaadc0 ("nbd: stop using the bdev everywhere")
Signed-off-by: NJosef Bacik <jbacik@fb.com>
Signed-off-by: NJens Axboe <axboe@kernel.dk>