Right now, bdrv_format_default_perms() is used by format parents
(generally). We want to switch to a model where most parents use a
single BdrvChildClass, which then decides the permissions based on the
child role. To do so, we have to split bdrv_format_default_perms() into
separate functions for each such role.

Note that bdrv_default_perms_for_storage() currently handles all DATA |
METADATA children.  A follow-up patch is going to split it further into
one function for each case.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200513110544.176672-18-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Right now, bdrv_format_default_perms() is used by format parents
(generally). We want to switch to a model where most parents use a
single BdrvChildClass, which then decides the permissions based on the
child role. To do so, we have to split bdrv_format_default_perms() into
separate functions for each such role.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200513110544.176672-17-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

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 mask will supplement BdrvChildClass when it comes to what role (or
combination of roles) a child takes for its parent.  It consists of
BdrvChildRoleBits values (which is an enum).

Because empty enums are not allowed, let us just start with it filled.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200513110544.176672-5-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@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>

We want to unify child_format and child_file at some point.  One of the
important things that set format drivers apart from other drivers is
that they do not expect other format nodes under them (except in the
backing chain), i.e. we must not probe formats inside of formats.  That
means we need something on which to distinguish format drivers from
others, and hence this flag.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NAlberto Garcia <berto@igalia.com>
Message-Id: <20200513110544.176672-3-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The commit, mirror, and blkreplay block nodes are filters, so they should
be marked as such.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200513110544.176672-2-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <20200429141126.85159-3-mreitz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This is just a bandaid to keep tests/test-replication working after
bdrv_make_empty() starts to assert that we're not trying to call it on a
read-only child.

For the real solution in the future, replication should not steal the
BdrvChild from its backing file (this is never correct to do!), but
instead have its own child node references, with the appropriate
permissions.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

bdrv_commit() already has a BlockBackend pointing to the BDS that we
want to empty, it just has the wrong permissions.

qemu-img commit has no BlockBackend pointing to the old backing file
yet, but introducing one is simple.

After this commit, bdrv_make_empty() is the only remaining caller of
BlockDriver.bdrv_make_empty().
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200429141126.85159-5-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
[kwolf: Fixed up reference output for 098]
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Two callers of BlockDriver.bdrv_make_empty() remain that should not call
this method directly.  Both do not have access to a BdrvChild, but they
can use a BlockBackend, so we add this function that lets them use it.
Signed-off-by: NMax Reitz <mreitz@redhat.com>
Message-Id: <20200429141126.85159-4-mreitz@redhat.com>
Reviewed-by: NEric Blake <eblake@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>

We made sure that iotests.py passes pylint. It would be a shame if we
allowed new patches in that break this again, so let's just add a
meta-test case that runs pylint on it.

While we don't pass mypy --strict yet, we can already run it with a few
options that would be part of --strict to make sure that we won't
regress on these aspects at least until we can enable the full thing.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <20200511163529.349329-3-kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

We need to fix only a few places so that iotests.py can pass
mypy --disallow-incomplete-defs, which seems to be a desirable option to
have enabled in the long run.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <20200511163529.349329-2-kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NJohn Snow <jsnow@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

If qemu in colo secondary mode is stopped, it crashes because
s->backup_job is canceled twice: First with job_cancel_sync_all()
in qemu_cleanup() and then in replication_stop().

Fix this by assigning NULL to s->backup_job when the job completes
so replication_stop() and replication_do_checkpoint() won't touch
the job.
Signed-off-by: NLukas Straub <lukasstraub2@web.de>
Message-Id: <20200511090801.7ed5d8f3@luklap>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This tests that the mirror job catches situations where the target node
has a different size than the source node. It must also forbid resize
operations when the job is already running.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200511135825.219437-5-kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

If the target is shorter than the source, mirror would copy data until
it reaches the end of the target and then fail with an I/O error when
trying to write past the end.

If the target is longer than the source, the mirror job would complete
successfully, but the target wouldn't actually be an accurate copy of
the source image (it would contain some additional garbage at the end).

Fix this by checking that both images have the same size when the job
starts.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200511135825.219437-4-kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

229 relies on the mirror running into an I/O error when the target is
smaller than the source. After changing mirror to catch this condition
while starting the job, this test case won't get a job that is paused
for an I/O error any more. Use blkdebug instead to inject an error.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <20200511135825.219437-3-kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

This patch makes the raw image the same size as the file in a different
format that is mirrored as raw to it to avoid errors when mirror starts
to enforce that source and target are the same size.

We check only that the first 512 bytes are zeroed (instead of 64k)
because some image formats create image files that are smaller than 64k,
so trying to read 64k would result in I/O errors. Apart from this, 512
is more appropriate anyway because the raw format driver protects
specifically the first 512 bytes.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <20200511135825.219437-2-kwolf@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

floatx80 x87 pseudo-denormal fixes

# gpg: Signature made Fri 15 May 2020 19:10:27 BST
# gpg:                using RSA key 7A481E78868B4DB6A85A05C064DF38E8AF7E215F
# gpg:                issuer "richard.henderson@linaro.org"
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>" [full]
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-fpu-20200515:
  softfloat: fix floatx80 pseudo-denormal round to integer
  softfloat: fix floatx80 pseudo-denormal comparisons
  softfloat: fix floatx80 pseudo-denormal addition / subtraction
  softfloat: silence sNaN for conversions to/from floatx80
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The softfloat function floatx80_round_to_int incorrectly handles the
case of a pseudo-denormal where only the high bit of the significand
is set, ignoring that bit (treating the number as an exact zero)
rather than treating the number as an alternative representation of
+/- 2^-16382 (which may round to +/- 1 depending on the rounding mode)
as hardware does.  Fix this check (simplifying the code in the
process).
Signed-off-by: NJoseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005042339420.22972@digraph.polyomino.org.uk>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

The softfloat floatx80 comparisons fail to allow for pseudo-denormals,
which should compare equal to corresponding values with biased
exponent 1 rather than 0.  Add an adjustment for that case when
comparing numbers with the same sign.
Signed-off-by: NJoseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005042338470.22972@digraph.polyomino.org.uk>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

The softfloat function addFloatx80Sigs, used for addition of values
with the same sign and subtraction of values with opposite sign, fails
to handle the case where the two values both have biased exponent zero
and there is a carry resulting from adding the significands, which can
occur if one or both values are pseudo-denormals (biased exponent
zero, explicit integer bit 1).  Add a check for that case, so making
the results match those seen on x86 hardware for pseudo-denormals.
Signed-off-by: NJoseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005042337570.22972@digraph.polyomino.org.uk>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Conversions between IEEE floating-point formats should convert
signaling NaNs to quiet NaNs.  Most of those in QEMU's softfloat code
do so, but those for floatx80 fail to.  Fix those conversions to
silence signaling NaNs as well.
Signed-off-by: NJoseph Myers <joseph@codesourcery.com>
Message-Id: <alpine.DEB.2.21.2005042336170.22972@digraph.polyomino.org.uk>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Various testing, tcg and plugin updates

  - fix bug in gdbstub tests that leave hanging QEMUs
  - tweak s390x travis test
  - re-factor guest_base handling
  - support "notes" in disassembler output
  - include guest address notes in out_asm
  - cleanup plugin headers and and constify hwaddr
  - updates MAINTAINERS for cpu-common.c

# gpg: Signature made Fri 15 May 2020 15:40:40 BST
# gpg:                using RSA key 6685AE99E75167BCAFC8DF35FBD0DB095A9E2A44
# gpg: Good signature from "Alex Bennée (Master Work Key) <alex.bennee@linaro.org>" [full]
# Primary key fingerprint: 6685 AE99 E751 67BC AFC8  DF35 FBD0 DB09 5A9E 2A44

* remotes/stsquad/tags/pull-testing-tcg-plugins-150520-2:
  MAINTAINERS: update the orphaned cpus-common.c file
  qemu/qemu-plugin: Make qemu_plugin_hwaddr_is_io() hwaddr argument const
  qemu/plugin: Move !CONFIG_PLUGIN stubs altogether
  qemu/plugin: Trivial code movement
  translate-all: include guest address in out_asm output
  disas: add optional note support to cap_disas
  disas: include an optional note for the start of disassembly
  accel/tcg: don't disable exec_tb trace events
  accel/tcg: Relax va restrictions on 64-bit guests
  exec/cpu-all: Use bool for have_guest_base
  linux-user: completely re-write init_guest_space
  travis.yml: Improve the --disable-tcg test on s390x
  tests/guest-debug: catch hanging guests
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

We forgot to update MAINTAINERS when this code was re-factored.

Fixes: 267f685bSigned-off-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-Id: <20200513173200.11830-5-alex.bennee@linaro.org>

Rename qemu_plugin_hwaddr_is_io() address argument 'haddr'
similarly to qemu_plugin_hwaddr_device_offset(), and make
it const.
Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Message-Id: <20200510171119.20827-4-f4bug@amsat.org>
Message-Id: <20200513173200.11830-4-alex.bennee@linaro.org>

Simplify the ifdef'ry by moving all stubs together.
Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Message-Id: <20200510171119.20827-3-f4bug@amsat.org>
Message-Id: <20200513173200.11830-3-alex.bennee@linaro.org>

Move the qemu_plugin_event enum declaration earlier.
This will make the next commit easier to review.
Signed-off-by: NPhilippe Mathieu-Daudé <f4bug@amsat.org>
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Message-Id: <20200510171119.20827-2-f4bug@amsat.org>
Message-Id: <20200513173200.11830-2-alex.bennee@linaro.org>

We already have information about where each guest instructions
representation starts stored in the tcg_ctx->gen_insn_data so we can
rectify the PC for faults. We can re-use this information to annotate
the out_asm output with guest instruction address which makes it a bit
easier to work out where you are especially with longer blocks. A
minor wrinkle is that some instructions get optimised away so we have
to scan forward until we find some actual generated code.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>

Message-Id: <20200513175134.19619-11-alex.bennee@linaro.org>