Commit Graph

2999 Commits

Author SHA1 Message Date
Max Reitz
7a25fcd056 block/mirror: Fix use-after-free
If @bs does not have any parents, the only reference to @mirror_top_bs
will be held by the BlockJob object after the bdrv_unref() following
block_job_create(). However, if block_job_create() fails, this reference
will not exist and @mirror_top_bs will have been deleted when we
goto fail.

The issue comes back at all later entries to the fail label: We delete
the BlockJob object before rolling back our changes to the node graph.
This means that we will delete @mirror_top_bs in the process.

All in all, whenever @bs does not have any parents and we go down the
fail path we will dereference @mirror_top_bs after it has been deleted.

Fix this by invoking bdrv_unref() only when block_job_create() was
successful and by bdrv_ref()'ing @mirror_top_bs in the fail path before
deleting the BlockJob object. Finally, bdrv_unref() it at the end of the
fail path after we actually no longer need it.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-04-07 14:44:05 +02:00
Kevin Wolf
0d0676a104 commit: Set commit_top_bs->total_sectors
Like in the mirror filter driver, we also need to set the image size for
the commit filter driver. This is less likely to be a problem in
practice than for the mirror because we're not at the active layer here,
but attaching new parents to a node in the middle of the chain is
possible, so the size needs to be correct anyway.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2017-04-07 14:44:05 +02:00
Kevin Wolf
02be4aeb93 commit: Set commit_top_bs->aio_context
The filter driver that is inserted by the commit job needs to use the
same AioContext as its parent and child nodes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
2017-04-07 14:44:05 +02:00
Kevin Wolf
d35ff5e6b3 block: Ignore guest dev permissions during incoming migration
Usually guest devices don't like other writers to the same image, so
they use blk_set_perm() to prevent this from happening. In the migration
phase before the VM is actually running, though, they don't have a
problem with writes to the image. On the other hand, storage migration
needs to be able to write to the image in this phase, so the restrictive
blk_set_perm() call of qdev devices breaks it.

This patch flags all BlockBackends with a qdev device as
blk->disable_perm during incoming migration, which means that the
requested permissions are stored in the BlockBackend, but not actually
applied to its root node yet.

Once migration has finished and the VM should be resumed, the
permissions are applied. If they cannot be applied (e.g. because the NBD
server used for block migration hasn't been shut down), resuming the VM
fails.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Tested-by: Kashyap Chamarthy <kchamart@redhat.com>
2017-04-07 14:44:05 +02:00
Peter Maydell
87cc4c6102 * MemoryRegionCache revert
* glib optimization workaround
 * fix "info lapic" segfault on isapc
 * fix QIOChannel memory leak
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* MemoryRegionCache revert
* glib optimization workaround
* fix "info lapic" segfault on isapc
* fix QIOChannel memory leak

# gpg: Signature made Mon 03 Apr 2017 18:17:00 BST
# gpg:                using RSA key 0xBFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  main-loop: Acquire main_context lock around os_host_main_loop_wait.
  exec: revert MemoryRegionCache
  nbd: fix memory leak on socket_connect failed
  ipmi: Fix macro issues
  target-i386: fix "info lapic" segfault on isapc
  iscsi: drop unused IscsiAIOCB.qiov field

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-04-04 11:40:55 +01:00
Max Reitz
86d1bd7098 block/parallels: Avoid overflows
Change the types of variables in allocate_clusters() to int64_t so we do
not have to worry about potential overflows.

Add an assertion that our accesses to s->bat[] do not result in a buffer
overflow and that the implicit conversion performed when invoking
bat_entry_off() does not result in an integer overflow.

Coverity-id: 1307776
Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170331170512.10381-1-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:40 +02:00
Eric Blake
0c1bd4692f qcow2: Discard unaligned tail when wiping image
There is a subtle difference between the fast (qcow2v3 with no
extra data) and slow path (qcow2v2 format [aka 0.10], or when a
snapshot is present) of qcow2_make_empty().  The slow path fails
to discard the final (partial) cluster of an unaligned image.

The problem stems from the fact that qcow2_discard_clusters() was
silently ignoring sub-cluster head and tail on unaligned requests.
A quick audit of all callers shows that qcow2_snapshot_create() has
always passed a cluster-aligned request since the call was added
in commit 1ebf561; qcow2_co_pdiscard() has passed a cluster-aligned
request since commit ecdbead taught the block layer about preferred
discard alignment; and qcow2_make_empty() was fixed to pass an
aligned start (but not necessarily end) in commit a3e1505.

Asserting that the start is always aligned also points out that we
now have a dead check: rounding the end offset down can never result
in a value less than the aligned start offset (the check was rendered
dead with commit ecdbead).  Meanwhile, we do not want to round the
end cluster down in the one case of the end offset matching the
(unaligned) file size - that final partial cluster should still be
discarded.

With those fixes in place, the fast and slow paths are back in sync
at discarding an entire image; the next patch will update
qemu-iotests to ensure we don't regress.

Note that bdrv_co_pdiscard ignores ALL partial cluster requests,
including the partial cluster at the end of an image; it can be
argued that the partial cluster at the end should be special-cased
so that a guest issuing discard requests at proper alignments
everywhere else can likewise empty the entire image.  But that
optimization is left for another day.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-id: 20170331185356.2479-3-eblake@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:40 +02:00
Markus Armbruster
d1c136885b sheepdog: Fix blockdev-add
Commit 831acdc "sheepdog: Implement bdrv_parse_filename()" and commit
d282f34 "sheepdog: Support blockdev-add" have different ideas on how
the QemuOpts parameters for the server address are named.  Fix that.
While there, rename BlockdevOptionsSheepdog member addr to server, for
consistency with BlockdevOptionsSsh, BlockdevOptionsGluster,
BlockdevOptionsNbd.

Commit 831acdc's example becomes

    --drive driver=sheepdog,server.type=inet,server.host=fido,server.port=7000,vdi=dolly

instead of

    --drive driver=sheepdog,host=fido,vdi=dolly

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Tested-by: Kashyap Chamarthy <kchamart@redhat.com>
Message-id: 1490895797-29094-10-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
Markus Armbruster
9445673ea6 nbd: Tidy up blockdev-add interface
SocketAddress is a simple union, and simple unions are awkward: they
have their variant members wrapped in a "data" object on the wire, and
require additional indirections in C.  I intend to limit its use to
existing external interfaces, and convert all internal interfaces to
SocketAddressFlat.

BlockdevOptionsNbd is an external interface using SocketAddress.  We
already use SocketAddressFlat elsewhere in blockdev-add.  Replace it
by SocketAddressFlat while we can (it's new in 2.9) for simplicity and
consistency.  For example,

    { "execute": "blockdev-add",
      "arguments": { "node-name": "foo", "driver": "nbd",
                     "server": { "type": "inet",
		                 "data": { "host": "localhost",
				           "port": "12345" } } } }

becomes

    { "execute": "blockdev-add",
      "arguments": { "node-name": "foo", "driver": "nbd",
                     "server": { "type": "inet",
		                 "host": "localhost", "port": "12345" } } }

Since the internal interfaces still take SocketAddress, this requires
conversion function socket_address_crumple().  It'll go away when I
update the interfaces.

Unfortunately, SocketAddress is also visible in -drive since 2.8:

    -drive if=none,driver=nbd,server.type=inet,server.data.host=127.0.0.1,server.data.port=12345

Nobody should be using it, as it's fairly new and has never been
documented, so adding still more compatibility gunk to keep it working
isn't worth the trouble.  You now have to use

    -drive if=none,driver=nbd,server.type=inet,server.host=127.0.0.1,server.port=12345

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1490895797-29094-9-git-send-email-armbru@redhat.com

[mreitz: Change iotest 147 accordingly]

Because of this interface change, iotest 147 has to be adapted.
Unfortunately, we cannot just flatten all of the addresses because
nbd-server-start still takes a plain SocketAddress. Therefore, we need
both and this is most easily achieved by writing the SocketAddress into
the code and flattening it where necessary.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170330221243.17333-1-mreitz@redhat.com

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
Markus Armbruster
8bc0673f6d qapi-schema: SocketAddressFlat variants 'vsock' and 'fd'
Note that the new variants are impossible in qemu_gluster_glfs_init(),
because the gconf->server can only come from qemu_gluster_parse_uri()
or qemu_gluster_parse_json(), and neither can create anything but
'inet' or 'unix'.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1490895797-29094-7-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
Markus Armbruster
fce5d5386d gluster: Prepare for SocketAddressFlat extension
qemu_gluster_glfs_init() and qemu_gluster_parse_json() rely on the
fact that SocketAddressFlatType has only two members
SOCKET_ADDRESS_FLAT_TYPE_INET and SOCKET_ADDRESS_FLAT_TYPE_UNIX.
Correct, but won't stay correct.  Make them more robust.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490895797-29094-6-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
Markus Armbruster
129c7d1c53 block: Document -drive problematic code and bugs
-blockdev and blockdev_add convert their arguments via QObject to
BlockdevOptions for qmp_blockdev_add(), which converts them back to
QObject, then to a flattened QDict.  The QDict's members are typed
according to the QAPI schema.

-drive converts its argument via QemuOpts to a (flat) QDict.  This
QDict's members are all QString.

Thus, the QType of a flat QDict member depends on whether it comes
from -drive or -blockdev/blockdev_add, except when the QAPI type maps
to QString, which is the case for 'str' and enumeration types.

The block layer core extracts generic configuration from the flat
QDict, and the block driver extracts driver-specific configuration.

Both commonly do so by converting (parts of) the flat QDict to
QemuOpts, which turns all values into strings.  Not exactly elegant,
but correct.

However, A few places access the flat QDict directly:

* Most of them access members that are always QString.  Correct.

* bdrv_open_inherit() accesses a boolean, carefully.  Correct.

* nfs_config() uses a QObject input visitor.  Correct only because the
  visited type contains nothing but QStrings.

* nbd_config() and ssh_config() use a QObject input visitor, and the
  visited types contain non-QStrings: InetSocketAddress members
  @numeric, @to, @ipv4, @ipv6.  -drive works as long as you don't try
  to use them (they're all optional).  @to is ignored anyway.

  Reproducer:
  -drive driver=ssh,server.host=h,server.port=22,server.ipv4,path=p
  -drive driver=nbd,server.type=inet,server.data.host=h,server.data.port=22,server.data.ipv4
  both fail with "Invalid parameter type for 'data.ipv4', expected: boolean"

Add suitable comments to all these places.  Mark the buggy ones FIXME.

"Fortunately", -drive's driver-specific options are entirely
undocumented.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1490895797-29094-5-git-send-email-armbru@redhat.com
[mreitz: Fixed two typos]
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
Markus Armbruster
ca0b64e5ed nbd sockets vnc: Mark problematic address family tests TODO
Certain features make sense only with certain address families.  For
instance, passing file descriptors requires AF_UNIX.  Testing
SocketAddress's saddr->type == SOCKET_ADDRESS_KIND_UNIX is obvious,
but problematic: it can't recognize AF_UNIX when type ==
SOCKET_ADDRESS_KIND_FD.

Mark such tests of saddr->type TODO.  We may want to check the address
family with getsockname() there.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1490895797-29094-2-git-send-email-armbru@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-04-03 17:11:39 +02:00
yaolujing
cc1e139139 nbd: fix memory leak on socket_connect failed
When TCP connection fails between nbd server and client,
the local var, sioc, memory leak.

This patch fixes the memory leak.

Signed-off-by: yaolujing <yaolujing@huawei.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-Id: <1491005709-29989-1-git-send-email-yaolujing@huawei.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-02 21:18:21 +02:00
Stefan Hajnoczi
b9afaba891 iscsi: drop unused IscsiAIOCB.qiov field
The IscsiAIOCB.qiov field has been unused since commit
063c3378a9 ("block/iscsi: introduce
bdrv_co_{readv, writev, flush_to_disk}") back in 2013.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20170327165005.22038-1-stefanha@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-04-02 21:17:47 +02:00
Max Reitz
34634ca286 block/curl: Check protocol prefix
If the user has explicitly specified a block driver and thus a protocol,
we have to make sure the URL's protocol prefix matches. Otherwise the
latter will silently override the former which might catch some users by
surprise.

Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 20170331120431.1767-3-mreitz@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-31 15:53:22 -04:00
Eric Blake
e98c6961c8 rbd: Fix regression in legacy key/values containing escaped :
Commit c7cacb3 accidentally broke legacy key-value parsing through
pseudo-filename parsing of -drive file=rbd://..., for any key that
contains an escaped ':'.  Such a key is surprisingly common, thanks
to mon_host specifying a 'host:port' string.  The break happens
because passing things from QDict through QemuOpts back to another
QDict requires that we pack our parsed key/value pairs into a string,
and then reparse that string, but the intermediate string that we
created ("key1=value1:key2=value2") lost the \: escaping that was
present in the original, so that we could no longer see which : were
used as separators vs. those used as part of the original input.

Fix it by collecting the key/value pairs through a QList, and
sending that list on a round trip through a JSON QString (as in
'["key1","value1","key2","value2"]') on its way through QemuOpts,
rather than hand-rolling our own string.  Since the string is only
handled internally, this was faster than creating a full-blown
struct of '[{"key1":"value1"},{"key2":"value2"}]', and safer at
guaranteeing order compared to '{"key1":"value1","key2":"value2"}'.

It would be nicer if we didn't have to round-trip through QemuOpts
in the first place, but that's a much bigger task for later.

Reproducer:
./x86_64-softmmu/qemu-system-x86_64 -nodefaults -nographic -qmp stdio \
-drive 'file=rbd:volumes/volume-ea141b5c-cdb3-4765-910d-e7008b209a70'\
':id=compute:key=AQAVkvxXAAAAABAA9ZxWFYdRmV+DSwKr7BKKXg=='\
':auth_supported=cephx\;none:mon_host=192.168.1.2\:6789'\
',format=raw,if=none,id=drive-virtio-disk0,'\
'serial=ea141b5c-cdb3-4765-910d-e7008b209a70,cache=writeback'

Even without an RBD setup, this serves a test of whether we get
the incorrect parser error of:
qemu-system-x86_64: -drive file=rbd:...cache=writeback: conf option 6789 has no value
or the correct behavior of hanging while trying to connect to
the requested mon_host of 192.168.1.2:6789.

Reported-by: Alexandru Avadanii <Alexandru.Avadanii@enea.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Message-id: 20170331152730.12514-1-eblake@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-31 13:53:57 -04:00
Markus Armbruster
2836284db6 rbd: Fix bugs around -drive parameter "server"
qemu_rbd_open() takes option parameters as a flattened QDict, with
keys of the form server.%d.host, server.%d.port, where %d counts up
from zero.

qemu_rbd_array_opts() extracts these values as follows.  First, it
calls qdict_array_entries() to find the list's length.  For each list
element, it formats the list's key prefix (e.g. "server.0."), then
creates a new QDict holding the options with that key prefix, then
converts that to a QemuOpts, so it can finally get the member values
from there.

If there's one surefire way to make code using QDict more awkward,
it's creating more of them and mixing in QemuOpts for good measure.

The extraction of keys starting with server.%d into another QDict
makes us ignore parameters like server.0.neither-host-nor-port
silently.

The conversion to QemuOpts abuses runtime_opts, as described a few
commits ago.

Rewrite to simply get the values straight from the options QDict.

Fixes -drive not to crash when server.*.* are present, but
server.*.host is absent.

Fixes -drive to reject invalid server.*.*.

Permits cleaning up runtime_opts.  Do that, and fix -drive to reject
bogus parameters host and port instead of silently ignoring them.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490691368-32099-11-git-send-email-armbru@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-28 10:01:21 -04:00
Markus Armbruster
464444fcc1 rbd: Revert -blockdev and -drive parameter auth-supported
This reverts half of commit 0a55679.  We're having second thoughts on
the QAPI schema (and thus the external interface), and haven't reached
consensus, yet.  Issues include:

* The implementation uses deprecated rados_conf_set() key
  "auth_supported".  No biggie.

* The implementation makes -drive silently ignore invalid parameters
  "auth" and "auth-supported.*.X" where X isn't "auth".  Fixable (in
  fact I'm going to fix similar bugs around parameter server), so
  again no biggie.

* BlockdevOptionsRbd member @password-secret applies only to
  authentication method cephx.  Should it be a variant member of
  RbdAuthMethod?

* BlockdevOptionsRbd member @user could apply to both methods cephx
  and none, but I'm not sure it's actually used with none.  If it
  isn't, should it be a variant member of RbdAuthMethod?

* The client offers a *set* of authentication methods, not a list.
  Should the methods be optional members of BlockdevOptionsRbd instead
  of members of list @auth-supported?  The latter begs the question
  what multiple entries for the same method mean.  Trivial question
  now that RbdAuthMethod contains nothing but @type, but less so when
  RbdAuthMethod acquires other members, such the ones discussed above.

* How BlockdevOptionsRbd member @auth-supported interacts with
  settings from a configuration file specified with @conf is
  undocumented.  I suspect it's untested, too.

Let's avoid painting ourselves into a corner now, and revert the
feature for 2.9.

Note that users can still configure authentication methods with a
configuration file.  They probably do that anyway if they use Ceph
outside QEMU as well.

Further note that this doesn't affect use of key "auth-supported" in
-drive file=rbd:...:key=value.

qemu_rbd_array_opts()'s parameter @type now must be RBD_MON_HOST,
which is silly.  This will be cleaned up shortly.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490691368-32099-9-git-send-email-armbru@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-28 10:01:21 -04:00
Markus Armbruster
078463977a rbd: Clean up qemu_rbd_create()'s detour through QemuOpts
The conversion from QDict to QemuOpts is pointless.  Simply get the
stuff straight from the QDict.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490691368-32099-8-git-send-email-armbru@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-28 10:00:57 -04:00
Markus Armbruster
cbf036b4f3 rbd: Clean up runtime_opts, fix -drive to reject filename
runtime_opts is used for three different purposes:

* qemu_rbd_open() uses it to accept options it recognizes, such as
  "pool" and "image".  Other .bdrv_open() methods do it similarly.

* qemu_rbd_open() accepts additional list-valued options
  auth-supported and server, with the help of qemu_rbd_array_opts().
  The list elements are again dictionaries.  qemu_rbd_array_opts()
  uses runtime_opts to accept their members.  Thus, runtime_opts
  contains recognized sub-sub-options "auth", "host", "port" in
  addition to recognized options.  No other block driver does that.

* qemu_rbd_create() uses it to convert the QDict produced by
  qemu_rbd_parse_filename() to QemuOpts.  No other block driver does
  that.  The keys produced by qemu_rbd_parse_filename() are "pool",
  "image", "snapshot", "conf", "user" and "keyvalue-pairs".
  qemu_rbd_open() accepts these, so no additional ones here.

This is a confusing mess.  Dates back to commit 0f9d252.  First step
to clean it up is documenting runtime_opts.desc[]:

* Reorder entries to match the QAPI schema, like we do in other block
  drivers.

* Document why the schema's "server" and "auth-supported" aren't in
  .desc[].

* Document why "keyvalue-pairs", "host", "port" and "auth" are in
  .desc[], but not the schema.

* Delete "filename", because none of the three users actually uses it.
  This fixes -drive to reject parameter filename instead of silently
  ignoring it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490691368-32099-7-git-send-email-armbru@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-28 09:53:16 -04:00
Markus Armbruster
82f20e8547 rbd: Don't accept -drive driver=rbd, keyvalue-pairs=...
The way we communicate extra key-value pairs from
qemu_rbd_parse_filename() to qemu_rbd_open() exposes option parameter
"keyvalue-pairs" on the command line.  It's not wanted there.  Hack:
rename the parameter to "=keyvalue-pairs" to make it inaccessible.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490691368-32099-6-git-send-email-armbru@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-28 09:53:16 -04:00
Markus Armbruster
8efb339dd4 rbd: Clean up after the previous commit
This code in qemu_rbd_parse_filename()

    found_str = qemu_rbd_next_tok(p, '\0', &p);
    p = found_str;

has no effect.  Drop it, and simplify qemu_rbd_next_tok().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490691368-32099-5-git-send-email-armbru@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-28 09:53:16 -04:00
Markus Armbruster
730b00bbfd rbd: Don't limit length of parameter values
We laboriously enforce that parameter values are between one and some
arbitrary limit in length.  Only RBD_MAX_IMAGE_NAME_SIZE comes from
librbd.h, and I'm not sure it applies.  Where the other limits come
from is unclear.

Drop the length checking.  The limits librbd actually imposes must be
checked by librbd anyway.

There's one minor complication: BDRVRBDState member name is a
fixed-size array.  Depends on the length limit.  Make it a pointer to
a dynamically allocated string.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490691368-32099-4-git-send-email-armbru@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-28 09:53:16 -04:00
Markus Armbruster
f51c363c2b rbd: Fix to cleanly reject -drive without pool or image
qemu_rbd_open() neglects to check pool and image are present.  Missing
image is caught by rbd_open(), but missing pool crashes.  Reproducer:

    $ qemu-system-x86_64 -nodefaults -drive driver=rbd,id=rbd,image=i,...
    terminate called after throwing an instance of 'std::logic_error'
      what():  basic_string::_M_construct null not valid
    Aborted (core dumped)

where ... is a working server.0.{host,port} configuration.

Doesn't affect -drive with file=..., because qemu_rbd_parse_filename()
always sets both pool and image.

Doesn't affect -blockdev, because pool and image are mandatory in the
QAPI schema.

Fix by adding the missing checks.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490691368-32099-3-git-send-email-armbru@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-28 09:53:16 -04:00
Denis V. Lunev
dc62da88b5 parallels: wrong call to bdrv_truncate
Parallels driver should not call bdrv_truncate if the image was opened
in the read-only mode. Without the patch
    qemu-img check harddisk.hds
asserts with
    bdrv_truncate: Assertion `child->perm & BLK_PERM_RESIZE' failed.

Parameters used on the write path are not needed if the image is opened
in the read-only mode.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Reported-by: Edgar Kaziahmedov <edos@virtuozzo.mipt.ru>
Message-id: 1490625488-7980-1-git-send-email-den@openvz.org
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-03-28 11:06:00 +01:00
Peter Maydell
eb06c9e2d3 * MTTCG fix for win32
* virtio-scsi assertion failure
 * mem-prealloc coverity fix
 * x86 migration revert which requires more thought
 * x86 instruction limit (avoids >2 page translation blocks)
 * nbd dead code cleanup
 * small memory.c logic fix
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* MTTCG fix for win32
* virtio-scsi assertion failure
* mem-prealloc coverity fix
* x86 migration revert which requires more thought
* x86 instruction limit (avoids >2 page translation blocks)
* nbd dead code cleanup
* small memory.c logic fix

# gpg: Signature made Mon 27 Mar 2017 17:03:04 BST
# gpg:                using RSA key 0xBFFBD25F78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"
# Primary key fingerprint: 46F5 9FBD 57D6 12E7 BFD4  E2F7 7E15 100C CD36 69B1
#      Subkey fingerprint: F133 3857 4B66 2389 866C  7682 BFFB D25F 78C7 AE83

* remotes/bonzini/tags/for-upstream:
  scsi-generic: Fill in opt_xfer_len in INQUIRY reply if it is zero
  Revert "apic: save apic_delivered flag"
  nbd: drop unused NBDClientSession.is_unix field
  win32: replace custom mutex and condition variable with native primitives
  mem-prealloc: fix sysconf(_SC_NPROCESSORS_ONLN) failure case.
  tcg/i386: Check the size of instruction being translated
  virtio-scsi: Fix acquire/release in dataplane handlers
  virtio-scsi: Make virtio_scsi_acquire/release public
  clear pending status before calling memory commit

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-03-27 17:34:50 +01:00
Peter Maydell
700f9ce0f9 block/file-posix.c: Fix unused variable warning on OpenBSD
On OpenBSD none of the ioctls probe_logical_blocksize() tries
exist, so the variable sector_size is unused. Refactor the
code to avoid this (and reduce the duplicated code).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 1490279788-12995-1-git-send-email-peter.maydell@linaro.org
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-03-27 17:28:34 +02:00
Kevin Wolf
e5bcf967fb file-posix: Make bdrv_flush() failure permanent without O_DIRECT
Success for bdrv_flush() means that all previously written data is safe
on disk. For fdatasync(), the best semantics we can hope for on Linux
(without O_DIRECT) is that all data that was written since the last call
was successfully written back. Therefore, and because we can't redo all
writes after a flush failure, we have to give up after a single
fdatasync() failure. After this failure, we would never be able to make
the promise that a successful bdrv_flush() makes.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-id: 20170322210005.16533-1-kwolf@redhat.com
Reviewed-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-03-27 16:53:42 +02:00
Paolo Bonzini
a12a712a7d nbd-client: fix handling of hungup connections
After the switch to reading replies in a coroutine, nothing is
reentering pending receive coroutines if the connection hangs.
Move nbd_recv_coroutines_enter_all to the reply read coroutine,
which is the place where hangups are detected.  nbd_teardown_connection
can simply wait for the reply read coroutine to detect the hangup
and clean up after itself.

This wouldn't be enough though because nbd_receive_reply returns 0
(rather than -EPIPE or similar) when reading from a hung connection.
Fix the return value check in nbd_read_reply_entry.

This fixes qemu-iotests 083.

Reported-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20170314111157.14464-1-pbonzini@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2017-03-27 16:50:36 +02:00
Stefan Hajnoczi
e4548bb640 nbd: drop unused NBDClientSession.is_unix field
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-Id: <20170327123223.1199-1-stefanha@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2017-03-27 14:41:01 +02:00
Eric Blake
67adf4b398 trace: Fix backwards mirror_yield parameters
block/trace-events lists the parameters for mirror_yield
consistently with other mirror events (cnt just after s, like in
mirror_before_sleep; in_flight last, like in mirror_yield_in_flight).
But the callers were passing parameters in the wrong order, leading
to poor trace messages, including type truncation when there are
more than 4G dirty sectors involved.  Broken since its introduction
in commit bd48bde.

While touching this, ensure that all callers use the same type
(uint64_t) for cnt, as a later patch will enable the compiler to do
stricter type-checking.

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-03-24 09:21:42 +00:00
Peter Maydell
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 -----END PGP SIGNATURE-----

Merge remote-tracking branch 'remotes/cody/tags/block-pull-request' into staging

# gpg: Signature made Wed 22 Mar 2017 17:28:56 GMT
# gpg:                using RSA key 0xBDBE7B27C0DE3057
# gpg: Good signature from "Jeffrey Cody <jcody@redhat.com>"
# gpg:                 aka "Jeffrey Cody <jeff@codyprime.org>"
# gpg:                 aka "Jeffrey Cody <codyprime@gmail.com>"
# Primary key fingerprint: 9957 4B4D 3474 90E7 9D98  D624 BDBE 7B27 C0DE 3057

* remotes/cody/tags/block-pull-request:
  blockjob: add devops to blockjob backends
  block-backend: add drained_begin / drained_end ops
  blockjob: add block_job_start_shim
  blockjob: avoid recursive AioContext locking

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-03-23 11:39:53 +00:00
John Snow
f4d9cc88ee block-backend: add drained_begin / drained_end ops
Allow block backends to forward drain requests to their devices/users.
The initial intended purpose for this patch is to allow BBs to forward
requests along to BlockJobs, which will want to pause if their associated
BB has entered a drained region.

Signed-off-by: John Snow <jsnow@redhat.com>
Reviewed-by: Jeff Cody <jcody@redhat.com>
Message-id: 20170316212351.13797-3-jsnow@redhat.com
Signed-off-by: Jeff Cody <jcody@redhat.com>
2017-03-22 13:26:27 -04:00
Edgar Kaziahmedov
ff5bbe56c6 parallels: fix default options parsing
parallels block driver is completely broken since commit
    commit 75cdcd1553
    Author: Markus Armbruster <armbru@redhat.com>
    Date:   Tue Feb 21 21:14:08 2017 +0100
    option: Fix checking of sizes for overflow and trailing crap
Right now even simple
    qemu-io -c "read 512 64k" 1.hds
ends up with
    Unexpected error in parse_option_size() at util/qemu-option.c:188:
    Parameter 'prealloc-size' expects a non-negative number below 2^64
    Aborted (core dumped)
The cure is simple - we should use 'M' as a suffix in default option value
instead of 'MiB'.

Signed-off-by: Edgar Kaziahmedov <edos@virtuozzo.mipt.ru>
Signed-off-by: Denis V. Lunev <den@openvz.org>
Message-id: 1490002022-22653-1-git-send-email-den@openvz.org
CC: Markus Armbruster <armbru@redhat.com>
CC: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2017-03-21 10:02:36 +00:00
Paolo Bonzini
eb048026aa curl: fix compilation on OpenBSD
EPROTO is not found in OpenBSD.   We usually use EIO when no better
errno is available, do that here too.

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Message-id: 20170317152412.8472-1-pbonzini@redhat.com
Reviewed-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
Tested-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2017-03-17 18:27:14 +00:00
Fam Zheng
c1cef67251 block: Always call bdrv_child_check_perm first
bdrv_child_set_perm alone is not very usable because the caller must
call bdrv_child_check_perm first. This is already encapsulated
conveniently in bdrv_child_try_set_perm, so remove the other prototypes
from the header and fix the one wrong caller, block/mirror.c.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-17 12:54:06 +01:00
Fam Zheng
fed414df9d file-posix: Don't leak fd in hdev_get_max_segments
This fixes a leaked fd introduced in commit 9103f1ce.

Signed-off-by: Fam Zheng <famz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-17 12:54:06 +01:00
Changlong Xie
37a9051cc7 replication: clarify permissions
Even if hidden_disk, secondary_disk are backing files, they all need
write permissions in replication scenario. Otherwise we will encouter
below exceptions on secondary side during adding nbd server:

{'execute': 'nbd-server-add', 'arguments': {'device': 'colo-disk', 'writable': true } }
{"error": {"class": "GenericError", "desc": "Conflicts with use by hidden-qcow2-driver as 'backing', which does not allow 'write' on sec-qcow2-driver-for-nbd"}}

CC: Zhang Hailiang <zhang.zhanghailiang@huawei.com>
CC: Zhang Chen <zhangchen.fnst@cn.fujitsu.com>
CC: Wen Congyang <wencongyang2@huawei.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-17 12:54:06 +01:00
Stefan Hajnoczi
6958349085 file-posix: clean up max_segments buffer termination
The following pattern is unsafe:

  char buf[32];
  ret = read(fd, buf, sizeof(buf));
  ...
  buf[ret] = 0;

If read(2) returns 32 then a byte beyond the end of the buffer is
zeroed.

In practice this buffer overflow does not occur because the sysfs
max_segments file only contains an unsigned short + '\n'.  The string is
always shorter than 32 bytes.

Regardless, avoid this pattern because static analysis tools might
complain and it could lead to real buffer overflows if copy-pasted
elsewhere in the codebase.

Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-17 12:54:06 +01:00
Kevin Wolf
dcbf37ce41 commit: Implement .bdrv_refresh_filename
We want query-block to return the right filename, even if a commit job
put a bdrv_commit_top on top of the actual image format driver. Let
bdrv_commit_top.bdrv_refresh_filename get the filename from its backing
file.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-03-13 12:49:33 +01:00
Kevin Wolf
fd4a6493bb mirror: Implement .bdrv_refresh_filename
We want query-block to return the right filename, even if a mirror job
put a bdrv_mirror_top on top of the actual image format driver. Let
bdrv_mirror_top.bdrv_refresh_filename get the filename from its backing
file.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-03-13 12:49:33 +01:00
Kevin Wolf
9196565866 commit: Implement bdrv_commit_top.bdrv_co_get_block_status
In some cases, bdrv_co_get_block_status() is called recursively for the
whole backing chain. The automatically inserted bdrv_commit_top filter
driver must not stop the recursion, so implement a callback that simply
forwards the request to bs->backing.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-03-13 12:49:33 +01:00
Kevin Wolf
b64aa44195 block: Request block status from *file for BDRV_BLOCK_RAW
This fixes bdrv_co_get_block_status() for the bdrv_mirror_top block
driver, which must fall through to bs->backing instead of bs->file.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2017-03-13 12:49:33 +01:00
Eric Blake
6f712ee080 vvfat: React to bdrv_is_allocated() errors
If bdrv_is_allocated() fails, we should react to that failure.
For 2 of the 3 callers, reporting the error was easy.  But in
cluster_was_modified() and its lone caller
get_cluster_count_for_direntry(), it's rather invasive to update
the logic to pass the error back; so there, I went with merely
documenting the issue by changing the return type to bool (in
all likelihood, treating the cluster as modified will then
trigger a read which will also fail, and eventually get to an
error - but given the appalling number of abort() calls in this
code, I'm not making it any worse).

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-13 12:49:33 +01:00
Eric Blake
666a9543fa backup: React to bdrv_is_allocated() errors
If bdrv_is_allocated() fails, we should immediately do the backup
error action, rather than attempting backup_do_cow() (although
that will likely fail too).

Signed-off-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-13 12:49:33 +01:00
Eric Blake
e32ccbc6e9 block: Drop unmaintained 'archipelago' driver
The driver has failed to build since commit da34e65, in qemu 2.6,
due to a missing include of qapi/error.h for error_setg().
Since no one has complained in three releases, it is easier to
remove the dead code than to keep it around, especially since it
is not being built by default and therefore prone to bitrot.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-13 12:49:33 +01:00
Fam Zheng
9103f1ceb4 file-posix: Consider max_segments for BlockLimits.max_transfer
BlockLimits.max_transfer can be too high without this fix, guest will
encounter I/O error or even get paused with werror=stop or rerror=stop. The
cause is explained below.

Linux has a separate limit, /sys/block/.../queue/max_segments, which in
the worst case can be more restrictive than the BLKSECTGET which we
already consider (note that they are two different things). So, the
failure scenario before this patch is:

1) host device has max_sectors_kb = 4096 and max_segments = 64;
2) guest learns max_sectors_kb limit from QEMU, but doesn't know
   max_segments;
3) guest issues e.g. a 512KB request thinking it's okay, but actually
   it's not, because it will be passed through to host device as an
   SG_IO req that has niov > 64;
4) host kernel doesn't like the segmenting of the request, and returns
   -EINVAL;

This patch checks the max_segments sysfs entry for the host device and
calculates a "conservative" bytes limit using the page size, which is
then merged into the existing max_transfer limit. Guest will discover
this from the usual virtual block device interfaces. (In the case of
scsi-generic, it will be done in the INQUIRY reply interception in
device model.)

The other possibility is to actually propagate it as a separate limit,
but it's not better. On the one hand, there is a big complication: the
limit is per-LUN in QEMU PoV (because we can attach LUNs from different
host HBAs to the same virtio-scsi bus), but the channel to communicate
it in a per-LUN manner is missing down the stack; on the other hand,
two limits versus one doesn't change much about the valid size of I/O
(because guest has no control over host segmenting).

Also, the idea to fall back to bounce buffering in QEMU, upon -EINVAL,
was explored. Unfortunately there is no neat way to ensure the bounce
buffer is less segmented (in terms of DMA addr) than the guest buffer.

Practically, this bug is not very common. It is only reported on a
Emulex (lpfc), so it's okay to get it fixed in the easier way.

Reviewed-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-13 12:49:33 +01:00
Vladimir Sementsov-Ogievskiy
a410a7f1af backup: allow target without .bdrv_get_info
Currently backup to nbd target is broken, as nbd doesn't have
.bdrv_get_info realization.

Signed-off-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-13 12:49:33 +01:00
Fam Zheng
b69f00dde4 commit: Don't use error_abort in commit_start
bdrv_set_backing_hd failure needn't be abort. Since we already have
error parameter, use it.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2017-03-07 14:53:29 +01:00