bdrv_format_default_perms() has one code path for backing files, and one
for storage files.  We want to pull them out into their own functions,
so make sure they are completely distinct before so the next patches
will be a bit cleaner.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200513110544.176672-16-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Any current user of child_file, child_format, and child_backing can and
should use this generic BdrvChildClass instead, as it can handle all of
these cases.  However, to be able to do so, the users must pass the
appropriate BdrvChildRole when the child is created/attached.  (The
following commits will take care of that.)
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200513110544.176672-15-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Make bdrv_child_cb_detach() call bdrv_backing_detach() for children with
a COW role (and drop the reverse call from bdrv_backing_detach()), so it
can be used for any child (with a proper role set).

Because so far no child has a proper role set, we need a temporary new
callback for child_backing.detach that ensures bdrv_backing_detach() is
called for all COW children that do not have their role set yet.

(Also, move bdrv_child_cb_detach() down to group it with
bdrv_inherited_options() and bdrv_child_cb_attach().)
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200513110544.176672-14-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Make bdrv_child_cb_attach() call bdrv_backing_attach() for children with
a COW role (and drop the reverse call from bdrv_backing_attach()), so it
can be used for any child (with a proper role set).

Because so far no child has a proper role set, we need a temporary new
callback for child_backing.attach that ensures bdrv_backing_attach() is
called for all COW children that do not have their role set yet.

(Also, move bdrv_child_cb_attach() down to group it with
bdrv_inherited_options().)
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200513110544.176672-13-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Let child_file's, child_format's, and child_backing's .inherit_options()
implementations fall back to bdrv_inherited_options() to show that it
would really work for all of these cases, if only the parents passed the
appropriate BdrvChildRole and parent_is_format values.

(Also, make bdrv_open_inherit(), the only place to explicitly call
bdrv_backing_options(), call bdrv_inherited_options() instead.)

This patch should incur only two visible changes, both for child_format
children, both of which are effectively bug fixes:

First, they no longer have discard=unmap set by default.  This reason it
was set is because bdrv_inherited_fmt_options() fell through to
bdrv_protocol_options(), and that set it because "format drivers take
care to send flushes and respect unmap policy".  None of the drivers
that use child_format for their children (quorum and blkverify) are
format drivers, though, so this reasoning does not apply here.

Second, they no longer have BDRV_O_NO_IO force-cleared.  child_format
was used solely for children that do not store any metadata and as such
will not be accessed by their parents as long as those parents do not
receive I/O themselves.  Thus, such children should inherit
BDRV_O_NO_IO.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200513110544.176672-12-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

After the series this patch belongs to, we want to have a common
BdrvChildClass that encompasses all of child_file, child_format, and
child_backing.  Such a single class needs a single .inherit_options()
implementation, and this patch introduces it.

The next patch will show how the existing implementations can fall back
to it just by passing appropriate BdrvChildRole and parent_is_format
values.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200513110544.176672-11-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The other two .inherit_options implementations specify exactly for what
case they are used in their name, so do it for this one as well.

(The actual intention behind this patch is to follow it up with a
generic bdrv_inherited_options() that works for all three cases.)
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200513110544.176672-10-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

We plan to unify the generic .inherit_options() functions.  The
resulting common function will need to decide whether to force-enable
format probing, force-disable it, or leave it as-is.  To make this
decision, it will need to know whether the parent node is a format node
or not (because we never want format probing if the parent is a format
node already (except for the backing chain)).
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200513110544.176672-9-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

For now, all callers (effectively) pass 0 and no callee evaluates thie
value.  Later patches will change both.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200513110544.176672-8-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

For now, all callers pass 0 and no callee evaluates this value.  Later
patches will change both.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200513110544.176672-7-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

For now, it is always set to 0.  Later patches in this series will
ensure that all callers pass an appropriate combination of flags.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200513110544.176672-6-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This structure nearly only contains parent callbacks for child state
changes.  It cannot really reflect a child's role, because different
roles may overlap (as we will see when real roles are introduced), and
because parents can have custom callbacks even when the child fulfills a
standard role.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Message-Id: <20200513110544.176672-4-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Right now, all users of bdrv_make_empty() call the BlockDriver method
directly.  That is not only bad style, it is also wrong, unless the
caller has a BdrvChild with a WRITE or WRITE_UNCHANGED permission.
(WRITE_UNCHANGED suffices, because callers generally use this function
to clear a node with a backing file after a commit operation.)

Introduce bdrv_make_empty() that verifies that it does.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200429141126.85159-2-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Now that there are no clients of bdrv_has_zero_init_truncate, none of
the drivers need to worry about providing it.

What's more, this eliminates a source of some confusion: a literal
reading of the documentation as written in ceaca56f and implemented in
commit 1dcaf527 claims that a driver which returns 0 for
bdrv_has_zero_init_truncate() must not return 1 for
bdrv_has_zero_init(); this condition was violated for parallels, qcow,
and sometimes for vdi, although in practice it did not matter since
those drivers also lacked .bdrv_co_truncate.
Signed-off-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200428202905.770727-10-eblake@redhat.com>
Acked-by: NRichard W.M. Jones <rjones@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Fix warning reported by Clang static code analyzer:

  block.c:3167:5: warning: Value stored to 'ret' is never read
      ret = bdrv_fill_options(&options, filename, &flags, &local_err);
      ^     ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Fixes: 462f5bcf
Reported-by: Clang Static Analyzer
Suggested-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NAlistair Francis <alistair.francis@wdc.com>
Signed-off-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200422133152.16770-2-philmd@redhat.com>
Signed-off-by: NLaurent Vivier <laurent@vivier.eu>

Now that node level interface bdrv_truncate() supports passing request
flags to the block driver, expose this on the BlockBackend level, too.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200424125448.63318-4-kwolf@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The previous few commits have made this more obvious, and removed the
one exception.  Time to clarify the documentation, and drop dead error
checking.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200424084338.26803-13-armbru@redhat.com>

bdrv_root_attach_child promises to drop child_bs reference on failure.
It does it on first handled failure path, but not on the second. Fix
that.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200324155921.23822-1-vsementsov@virtuozzo.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Instead of checking the .bdrv_co_create_opts to see if we need the
fallback, just implement the .bdrv_co_create_opts in the drivers that
need it.

This way we don't break various places that need to know if the
underlying protocol/format really supports image creation, and this way
we still allow some drivers to not support image creation.

Fixes: fd17146c
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1816007

Note that technically this driver reverts the image creation fallback
for the vxhs driver since I don't have a means to test it, and IMHO it
is better to leave it not supported as it was prior to generic image
creation patches.

Also drop iscsi_create_opts which was left accidentally.
Signed-off-by: NMaxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200326011218.29230-3-mlevitsk@redhat.com>
Reviewed-by: NDenis V. Lunev <den@openvz.org>
[mreitz: Fixed alignment, and moved bdrv_co_create_opts_simple() and
         bdrv_create_opts_simple from block.h into block_int.h]
Signed-off-by: NMax Reitz <mreitz@redhat.com>

This will allow the reuse of a single generic .bdrv_co_create
implementation for several drivers.
No functional changes.
Signed-off-by: NMaxim Levitsky <mlevitsk@redhat.com>
Message-Id: <20200326011218.29230-2-mlevitsk@redhat.com>
Reviewed-by: NDenis V. Lunev <den@openvz.org>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

There is a use-after-free possible: bdrv_unref_child() leaves
bs->backing freed but not NULL. bdrv_attach_child may produce nested
polling loop due to drain, than access of freed pointer is possible.

I've produced the following crash on 30 iotest with modified code. It
does not reproduce on master, but still seems possible:

    #0  __strcmp_avx2 () at /lib64/libc.so.6
    #1  bdrv_backing_overridden (bs=0x55c9d3cc2060) at block.c:6350
    #2  bdrv_refresh_filename (bs=0x55c9d3cc2060) at block.c:6404
    #3  bdrv_backing_attach (c=0x55c9d48e5520) at block.c:1063
    #4  bdrv_replace_child_noperm
        (child=child@entry=0x55c9d48e5520,
        new_bs=new_bs@entry=0x55c9d3cc2060) at block.c:2290
    #5  bdrv_replace_child
        (child=child@entry=0x55c9d48e5520,
        new_bs=new_bs@entry=0x55c9d3cc2060) at block.c:2320
    #6  bdrv_root_attach_child
        (child_bs=child_bs@entry=0x55c9d3cc2060,
        child_name=child_name@entry=0x55c9d241d478 "backing",
        child_role=child_role@entry=0x55c9d26ecee0 <child_backing>,
        ctx=<optimized out>, perm=<optimized out>, shared_perm=21,
        opaque=0x55c9d3c5a3d0, errp=0x7ffd117108e0) at block.c:2424
    #7  bdrv_attach_child
        (parent_bs=parent_bs@entry=0x55c9d3c5a3d0,
        child_bs=child_bs@entry=0x55c9d3cc2060,
        child_name=child_name@entry=0x55c9d241d478 "backing",
        child_role=child_role@entry=0x55c9d26ecee0 <child_backing>,
        errp=errp@entry=0x7ffd117108e0) at block.c:5876
    #8  in bdrv_set_backing_hd
        (bs=bs@entry=0x55c9d3c5a3d0,
        backing_hd=backing_hd@entry=0x55c9d3cc2060,
        errp=errp@entry=0x7ffd117108e0)
        at block.c:2576
    #9  stream_prepare (job=0x55c9d49d84a0) at block/stream.c:150
    #10 job_prepare (job=0x55c9d49d84a0) at job.c:761
    #11 job_txn_apply (txn=<optimized out>, fn=<optimized out>) at
        job.c:145
    #12 job_do_finalize (job=0x55c9d49d84a0) at job.c:778
    #13 job_completed_txn_success (job=0x55c9d49d84a0) at job.c:832
    #14 job_completed (job=0x55c9d49d84a0) at job.c:845
    #15 job_completed (job=0x55c9d49d84a0) at job.c:836
    #16 job_exit (opaque=0x55c9d49d84a0) at job.c:864
    #17 aio_bh_call (bh=0x55c9d471a160) at util/async.c:117
    #18 aio_bh_poll (ctx=ctx@entry=0x55c9d3c46720) at util/async.c:117
    #19 aio_poll (ctx=ctx@entry=0x55c9d3c46720,
        blocking=blocking@entry=true)
        at util/aio-posix.c:728
    #20 bdrv_parent_drained_begin_single (poll=true, c=0x55c9d3d558f0)
        at block/io.c:121
    #21 bdrv_parent_drained_begin_single (c=c@entry=0x55c9d3d558f0,
        poll=poll@entry=true)
        at block/io.c:114
    #22 bdrv_replace_child_noperm
        (child=child@entry=0x55c9d3d558f0,
        new_bs=new_bs@entry=0x55c9d3d27300) at block.c:2258
    #23 bdrv_replace_child
        (child=child@entry=0x55c9d3d558f0,
        new_bs=new_bs@entry=0x55c9d3d27300) at block.c:2320
    #24 bdrv_root_attach_child
        (child_bs=child_bs@entry=0x55c9d3d27300,
        child_name=child_name@entry=0x55c9d241d478 "backing",
        child_role=child_role@entry=0x55c9d26ecee0 <child_backing>,
        ctx=<optimized out>, perm=<optimized out>, shared_perm=21,
        opaque=0x55c9d3cc2060, errp=0x7ffd11710c60) at block.c:2424
    #25 bdrv_attach_child
        (parent_bs=parent_bs@entry=0x55c9d3cc2060,
        child_bs=child_bs@entry=0x55c9d3d27300,
        child_name=child_name@entry=0x55c9d241d478 "backing",
        child_role=child_role@entry=0x55c9d26ecee0 <child_backing>,
        errp=errp@entry=0x7ffd11710c60) at block.c:5876
    #26 bdrv_set_backing_hd
        (bs=bs@entry=0x55c9d3cc2060,
        backing_hd=backing_hd@entry=0x55c9d3d27300,
        errp=errp@entry=0x7ffd11710c60)
        at block.c:2576
    #27 stream_prepare (job=0x55c9d495ead0) at block/stream.c:150
    ...
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200316060631.30052-2-vsementsov@virtuozzo.com>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

bdrv_do_find_format() calls strcmp() using BlockDriver::format_name
as argument, which must not be NULL. Assert this field is not null
when we register a block driver in bdrv_register().
Reported-by: NMansour Ahmadi <ManSoSec@gmail.com>
Signed-off-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200318222235.23856-1-philmd@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Using the new 'bdrv_co_delete_file' interface, a pure co_routine function
'bdrv_co_delete_file' inside block.c can can be used in a way similar of
the existing bdrv_create_file to to clean up a created file.

We're creating a pure co_routine because the only caller of
'bdrv_co_delete_file' will be already in co_routine context, thus there
is no need to add all the machinery to check for qemu_in_coroutine() and
create a separated co_routine to do the job.
Suggested-by: NDaniel P. Berrangé <berrange@redhat.com>
Signed-off-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20200130213907.2830642-3-danielhb413@gmail.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

external_snapshot_prepare() tries to move the overlay to the AioContext
of the backing file (the snapshotted node). However, it's possible that
this doesn't work, but the backing file can instead be moved to the
overlay's AioContext (e.g. opening the backing chain for a mirror
target).

bdrv_append() already indirectly uses bdrv_attach_node(), which takes
care to move nodes to make sure they use the same AioContext and which
tries both directions.

So the problem has a simple fix: Just delete the unnecessary extra
bdrv_try_set_aio_context() call in external_snapshot_prepare() and
instead assert in bdrv_append() that both nodes were indeed moved to the
same AioContext.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <20200310113831.27293-6-kwolf@redhat.com>
Tested-by: NPeter Krempa <pkrempa@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <20200310113831.27293-2-kwolf@redhat.com>
Reviewed-by: NPeter Krempa <pkrempa@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This patch allows bdrv_reopen() (and therefore the x-blockdev-reopen QMP
command) to attach a node as the new backing file even if the node is in
a different AioContext than the parent if one of both nodes can be moved
to the AioContext of the other node.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Tested-by: NPeter Krempa <pkrempa@redhat.com>
Message-Id: <20200306141413.30705-3-kwolf@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Add another step in the reopen process where driver can execute code
after permission changes are comitted.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Message-Id: <adc02cf591c3cb34e98e33518eb1c540a0f27db1.1582893284.git.pkrempa@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

@options is leaked by the first two return statements in this function.

Note that blk_new_open() takes the reference to @options even on
failure, so all we need to do to fix the leak is to move the QDict
allocation down to where we actually need it.

Reported-by: Coverity (CID 1419884)
Fixes: fd17146c
       ("block: Generic file creation fallback")
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200225155618.133412-1-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

QLIST_REMOVE() assumes the element is in a list.  It also leaves the
element's linked list pointers dangling.

Introduce a safe version of QLIST_REMOVE() and convert open-coded
instances of this pattern.
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Reviewed-by: NSergio Lopez <slp@redhat.com>
Message-id: 20200214171712.541358-4-stefanha@redhat.com
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

If a protocol driver does not support image creation, we can see whether
maybe the file exists already.  If so, just truncating it will be
sufficient.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200122164532.178040-3-mreitz@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

When a management application manages node names there's no reason to
recurse into backing images in the output of query-named-block-nodes.

Add a parameter to the command which will return just the top level
structs.
Signed-off-by: NPeter Krempa <pkrempa@redhat.com>
Message-Id: <4470f8c779abc404dcf65e375db195cd91a80651.1579509782.git.pkrempa@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
[mreitz: Fixed coding style]
Signed-off-by: NMax Reitz <mreitz@redhat.com>

It no longer has any users.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200218103454.296704-11-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Let check_to_replace_node() use the more specialized
bdrv_recurse_can_replace() instead of
bdrv_recurse_is_first_non_filter(), which is too restrictive (or, in the
case of quorum, sometimes not restrictive enough).
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200218103454.296704-10-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

After a couple of follow-up patches, this function will replace
bdrv_recurse_is_first_non_filter() in check_to_replace_node().

bdrv_recurse_is_first_non_filter() is both not sufficiently specific for
check_to_replace_node() (it allows cases that should not be allowed,
like replacing child nodes of quorum with dissenting data that have more
parents than just quorum), and it is too restrictive (it is perfectly
fine to replace filters).
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200218103454.296704-7-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

It is unused now.  (And it was ugly because it needed to explore all BDS
chains from the top.)
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Message-Id: <20200218103454.296704-4-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Fixes: 132ada80Signed-off-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200218094402.26625-4-philmd@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

If we call the qmp 'query-block' while qemu is working on
'block-commit', it will cause memleaks, the memory leak stack is as
follow:

Indirect leak of 12360 byte(s) in 3 object(s) allocated from:
    #0 0x7f80f0b6d970 in __interceptor_calloc (/lib64/libasan.so.5+0xef970)
    #1 0x7f80ee86049d in g_malloc0 (/lib64/libglib-2.0.so.0+0x5249d)
    #2 0x55ea95b5bb67 in qdict_new /mnt/sdb/qemu-4.2.0-rc0/qobject/qdict.c:29
    #3 0x55ea956cd043 in bdrv_refresh_filename /mnt/sdb/qemu-4.2.0-rc0/block.c:6427
    #4 0x55ea956cc950 in bdrv_refresh_filename /mnt/sdb/qemu-4.2.0-rc0/block.c:6399
    #5 0x55ea956cc950 in bdrv_refresh_filename /mnt/sdb/qemu-4.2.0-rc0/block.c:6399
    #6 0x55ea956cc950 in bdrv_refresh_filename /mnt/sdb/qemu-4.2.0-rc0/block.c:6399
    #7 0x55ea958818ea in bdrv_block_device_info /mnt/sdb/qemu-4.2.0-rc0/block/qapi.c:56
    #8 0x55ea958879de in bdrv_query_info /mnt/sdb/qemu-4.2.0-rc0/block/qapi.c:392
    #9 0x55ea9588b58f in qmp_query_block /mnt/sdb/qemu-4.2.0-rc0/block/qapi.c:578
    #10 0x55ea95567392 in qmp_marshal_query_block qapi/qapi-commands-block-core.c:95

Indirect leak of 4120 byte(s) in 1 object(s) allocated from:
    #0 0x7f80f0b6d970 in __interceptor_calloc (/lib64/libasan.so.5+0xef970)
    #1 0x7f80ee86049d in g_malloc0 (/lib64/libglib-2.0.so.0+0x5249d)
    #2 0x55ea95b5bb67 in qdict_new /mnt/sdb/qemu-4.2.0-rc0/qobject/qdict.c:29
    #3 0x55ea956cd043 in bdrv_refresh_filename /mnt/sdb/qemu-4.2.0-rc0/block.c:6427
    #4 0x55ea956cc950 in bdrv_refresh_filename /mnt/sdb/qemu-4.2.0-rc0/block.c:6399
    #5 0x55ea956cc950 in bdrv_refresh_filename /mnt/sdb/qemu-4.2.0-rc0/block.c:6399
    #6 0x55ea9569f301 in bdrv_backing_attach /mnt/sdb/qemu-4.2.0-rc0/block.c:1064
    #7 0x55ea956a99dd in bdrv_replace_child_noperm /mnt/sdb/qemu-4.2.0-rc0/block.c:2283
    #8 0x55ea956b9b53 in bdrv_replace_node /mnt/sdb/qemu-4.2.0-rc0/block.c:4196
    #9 0x55ea956b9e49 in bdrv_append /mnt/sdb/qemu-4.2.0-rc0/block.c:4236
    #10 0x55ea958c3472 in commit_start /mnt/sdb/qemu-4.2.0-rc0/block/commit.c:306
    #11 0x55ea94b68ab0 in qmp_block_commit /mnt/sdb/qemu-4.2.0-rc0/blockdev.c:3459
    #12 0x55ea9556a7a7 in qmp_marshal_block_commit qapi/qapi-commands-block-core.c:407

Fixes: bb808d5fReported-by: NEuler Robot <euler.robot@huawei.com>
Signed-off-by: NPan Nengyuan <pannengyuan@huawei.com>
Message-id: 20200116085600.24056-1-pannengyuan@huawei.com
Signed-off-by: NMax Reitz <mreitz@redhat.com>

This is a bit more efficient than having to allocate and free memory
for each new permission.

The default size (30) is enough for "consistent read, write, resize".
Signed-off-by: NAlberto Garcia <berto@igalia.com>
Message-id: 20200110171518.22168-1-berto@igalia.com
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>

Signed-off-by: NAarushi Mehta <mehta.aaru20@gmail.com>
Acked-by: NStefano Garzarella <sgarzare@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>
Message-id: 20200120141858.587874-8-stefanha@redhat.com
Message-Id: <20200120141858.587874-8-stefanha@redhat.com>
Signed-off-by: NStefan Hajnoczi <stefanha@redhat.com>

We can save some LoC in xdbg_graph_add_edge() by using
bdrv_qapi_perm_to_blk_perm().
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-id: 20191108123455.39445-3-mreitz@redhat.com
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: NMax Reitz <mreitz@redhat.com>