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: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

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: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

In bdrv_open_inherit(), the filename is refreshed after opening the
backing file, but we neglected to do the same when the backing file
changes later.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

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: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

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: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

All callers pass false now, so the parameter can go away again.
Signed-off-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>

Migration is the only code left in the tree that does not react
to bdrv_is_allocated() failures.  But as there is no useful way
to react to the failure, and we are merely skipping unallocated
sectors on success, just document that our choice of handling
is intended.
Signed-off-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

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: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

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: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

The driver has failed to build since commit da34e65c, 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: NEric Blake <eblake@redhat.com>
Reviewed-by: NMax Reitz <mreitz@redhat.com>
Reviewed-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

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: NPaolo Bonzini <pbonzini@redhat.com>
Signed-off-by: NFam Zheng <famz@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

Currently backup to nbd target is broken, as nbd doesn't have
.bdrv_get_info realization.
Signed-off-by: NVladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Signed-off-by: NKevin Wolf <kwolf@redhat.com>

2.9 bugfixes for ohci and qxl

# gpg: Signature made Thu 09 Mar 2017 09:09:44 GMT
# gpg:                using RSA key 0x4CB6D8EED3E87138
# gpg: Good signature from "Gerd Hoffmann (work) <kraxel@redhat.com>"
# gpg:                 aka "Gerd Hoffmann <gerd@kraxel.org>"
# gpg:                 aka "Gerd Hoffmann (private) <kraxel@gmail.com>"
# Primary key fingerprint: A032 8CFF B93A 17A7 9901  FE7D 4CB6 D8EE D3E8 7138

* remotes/kraxel/tags/pull-fixes-20170309-1:
  qxl: clear guest_cursor on QXL_CURSOR_HIDE
  ohci: relax link check
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Make sure we don't leave guest_cursor pointing into nowhere.  This might
lead to (rare) live migration failures, due to target trying to restore
the cursor from the stale pointer.

Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1421788Reported-by: NDr. David Alan Gilbert <dgilbert@redhat.com>
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NMarc-André Lureau <marcandre.lureau@redhat.com>
Message-id: 1488789111-27340-1-git-send-email-kraxel@redhat.com

The strict td link limit added by commit "95ed5693 usb: ohci: limit the
number of link eds" causes problems with macos guests.  Lets raise the
limit.
Reported-by: NProgrammingkid <programmingkidx@gmail.com>
Reported-by: NHoward Spoelstra <hsp.cat7@gmail.com>
Signed-off-by: NGerd Hoffmann <kraxel@redhat.com>
Reviewed-by: NBALATON Zoltan <balaton@eik.bme.hu>
Reviewed-by: NJohn Arbuckle <programmingkidx@gmail.com>
Message-id: 1488876018-31576-1-git-send-email-kraxel@redhat.com

Block layer fixes for 2.9.0-rc0

# gpg: Signature made Tue 07 Mar 2017 14:59:18 GMT
# gpg:                using RSA key 0x7F09B272C88F2FD6
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>"
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* remotes/kevin/tags/for-upstream: (27 commits)
  commit: Don't use error_abort in commit_start
  block: Don't use error_abort in blk_new_open
  sheepdog: Support blockdev-add
  qapi-schema: Rename SocketAddressFlat's variant tcp to inet
  qapi-schema: Rename GlusterServer to SocketAddressFlat
  gluster: Plug memory leaks in qemu_gluster_parse_json()
  gluster: Don't duplicate qapi-util.c's qapi_enum_parse()
  gluster: Drop assumptions on SocketTransport names
  sheepdog: Implement bdrv_parse_filename()
  sheepdog: Use SocketAddress and socket_connect()
  sheepdog: Report errors in pseudo-filename more usefully
  sheepdog: Don't truncate long VDI name in _open(), _create()
  sheepdog: Fix snapshot ID parsing in _open(), _create, _goto()
  sheepdog: Mark sd_snapshot_delete() lossage FIXME
  sheepdog: Fix error handling sd_create()
  sheepdog: Fix error handling in sd_snapshot_delete()
  sheepdog: Defuse time bomb in sd_open() error handling
  block: Fix error handling in bdrv_replace_in_backing_chain()
  block: Handle permission errors in change_parent_backing_link()
  block: Ignore multiple children in bdrv_check_update_perm()
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

block: Command line option -blockdev

# gpg: Signature made Tue 07 Mar 2017 15:07:59 GMT
# gpg:                using RSA key 0x3870B400EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"
# Primary key fingerprint: 354B C8B3 D7EB 2A6B 6867  4E5F 3870 B400 EB91 8653

* remotes/armbru/tags/pull-block-2017-02-28-v4: (24 commits)
  keyval: Support lists
  docs/qapi-code-gen.txt: Clarify naming rules
  qapi: Improve how keyval input visitor reports unexpected dicts
  block: Initial implementation of -blockdev
  qapi: New qobject_input_visitor_new_str() for convenience
  keyval: Restrict key components to valid QAPI names
  qapi: New parse_qapi_name()
  test-qapi-util: New, covering qapi/qapi-util.c
  monitor: Assert qmp_schema_json[] is sane
  test-visitor-serialization: Pass &error_abort to qobject_from_json()
  check-qjson: Test errors from qobject_from_json()
  block: More detailed syntax error reporting for JSON filenames
  qobject: Propagate parse errors through qobject_from_json()
  test-qobject-input-visitor: Abort earlier on bad test input
  qjson: Abort earlier on qobject_from_jsonf() misuse
  libqtest: Fix qmp() & friends to abort on JSON parse errors
  qobject: Propagate parse errors through qobject_from_jsonv()
  qapi: Factor out common qobject_input_get_keyval()
  qapi: Factor out common part of qobject input visitor creation
  test-keyval: Cover use with qobject input visitor
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Additionally permit non-negative integers as key components.  A
dictionary's keys must either be all integers or none.  If all keys
are integers, convert the dictionary to a list.  The set of keys must
be [0,N].

Examples:

* list.1=goner,list.0=null,list.1=eins,list.2=zwei
  is equivalent to JSON [ "null", "eins", "zwei" ]

* a.b.c=1,a.b.0=2
  is inconsistent: a.b.c clashes with a.b.0

* list.0=null,list.2=eins,list.2=zwei
  has a hole: list.1 is missing

Similar design flaw as for objects: there is no way to denote an empty
list.  While interpreting "key absent" as empty list seems natural
(removing a list member from the input string works when there are
multiple ones, so why not when there's just one), it doesn't work:
"key absent" already means "optional list absent", which isn't the
same as "empty list present".

Update the keyval object visitor to use this a.0 syntax in error
messages rather than the usual a[0].
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <1488317230-26248-25-git-send-email-armbru@redhat.com>
[Off-by-one fix squashed in, as per Kevin's review]
Reviewed-by: NKevin Wolf <kwolf@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-24-git-send-email-armbru@redhat.com>

Incorrect option

    -blockdev node-name=foo,driver=file,filename=foo.img,aio.unmap=on

is rejected with "Invalid parameter type for 'aio', expected: string".
To make sense of this, you almost have to translate it into the
equivalent QMP command

    { "execute": "blockdev-add", "arguments": { "node-name": "foo", "driver": "file", "filename": "foo.img", "aio": { "unmap": true } } }

Improve the error message to "Parameters 'aio.*' are unexpected".
Take care not to confuse the case "unexpected nested parameters"
(i.e. the object is a QDict or QList) with the case "non-string scalar
parameter".  The latter is a misuse of the visitor, and should perhaps
be an assertion.  Note that test-qobject-input-visitor exercises this
misuse in test_visitor_in_int_keyval(), test_visitor_in_bool_keyval()
and test_visitor_in_number_keyval().
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-23-git-send-email-armbru@redhat.com>

The new command line option -blockdev works like QMP command
blockdev-add.

The option argument may be given in JSON syntax, exactly as in QMP.
Example usage:

    -blockdev '{"node-name": "foo", "driver": "raw", "file": {"driver": "file", "filename": "foo.img"} }'

The JSON argument doesn't exactly blend into the existing option
syntax, so the traditional KEY=VALUE,... syntax is also supported,
using dotted keys to do the nesting:

    -blockdev node-name=foo,driver=raw,file.driver=file,file.filename=foo.img

This does not yet support lists, but that will be addressed shortly.

Note that calling qmp_blockdev_add() (say via qmp_marshal_block_add())
right away would crash.  We need to stash the configuration for later
instead.  This is crudely done, and bypasses QemuOpts, even though
storing configuration is what QemuOpts is for.  Need to revamp option
infrastructure to support QAPI types like BlockdevOptions.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1488317230-26248-22-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <1488317230-26248-21-git-send-email-armbru@redhat.com>

Until now, key components are separated by '.'.  This leaves little
room for evolving the syntax, and is incompatible with the __RFQDN_
prefix convention for downstream extensions.

Since key components will be commonly used as QAPI member names by the
QObject input visitor, we can just as well borrow the QAPI naming
rules here: letters, digits, hyphen and period starting with a letter,
with an optional __RFQDN_ prefix for downstream extensions.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-20-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1488317230-26248-19-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-18-git-send-email-armbru@redhat.com>

qmp_query_qmp_schema() parses qmp_schema_json[] with
qobject_from_json().  This must not fail, so pass &error_abort.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-17-git-send-email-armbru@redhat.com>

qmp_deserialize() calls qobject_from_json() ignoring errors.  It
passes the result to qobject_input_visitor_new(), which asserts it's
not null.  Therefore, we can just as well pass &error_abort to
qobject_from_json().
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-16-git-send-email-armbru@redhat.com>

Pass &error_abort with known-good input.  Else pass &err and check
what comes back.  This demonstrates that the parser fails silently for
many errors.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-15-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-14-git-send-email-armbru@redhat.com>

The next few commits will put the errors to use where appropriate.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1488317230-26248-13-git-send-email-armbru@redhat.com>

visitor_input_test_init_internal() parses test input with
qobject_from_jsonv(), and asserts it succeeds.  Pass &error_abort for
good measure.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-12-git-send-email-armbru@redhat.com>

Ignoring errors first, then asserting success is suboptimal.  Pass
&error_abort instead, so we abort earlier, and hopefully get more
useful clues on what's wrong.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-11-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-10-git-send-email-armbru@redhat.com>

The next few commits will put the errors to use where appropriate.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-9-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Message-Id: <1488317230-26248-8-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-7-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-6-git-send-email-armbru@redhat.com>

Currently the QObjectInputVisitor assumes that all scalar values are
directly represented as the final types declared by the thing being
visited. i.e. it assumes an 'int' is using QInt, and a 'bool' is using
QBool, etc.  This is good when QObjectInputVisitor is fed a QObject
that came from a JSON document on the QMP monitor, as it will strictly
validate correctness.

To allow QObjectInputVisitor to be reused for visiting a QObject
originating from keyval_parse(), an alternative mode is needed where
all the scalars types are represented as QString and converted on the
fly to the final desired type.
Signed-off-by: NDaniel P. Berrange <berrange@redhat.com>
Message-Id: <1475246744-29302-8-git-send-email-berrange@redhat.com>

Rebased, conflicts resolved, commit message updated to refer to
keyval_parse().  autocast replaced by keyval in identifiers,
noautocast replaced by fail in tests.

Fix qobject_input_type_uint64_keyval() not to reject '-', for QemuOpts
compatibility: replace parse_uint_full() by open-coded
parse_option_number().  The next commit will add suitable tests.
Leave out the fancy ERANGE error reporting for now, but add a TODO
comment.  Add it qobject_input_type_int64_keyval() and
qobject_input_type_number_keyval(), too.

Open code parse_option_bool() and parse_option_size() so we have to
call qobject_input_get_name() only when actually needed.  Again, leave
out ERANGE error reporting for now.

QAPI/QMP downstream extension prefixes __RFQDN_ don't work, because
keyval_parse() splits them at '.'.  This will be addressed later in
the series.

qobject_input_type_int64_keyval(), qobject_input_type_uint64_keyval(),
qobject_input_type_number_keyval() tweaked for style.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-5-git-send-email-armbru@redhat.com>

keyval_parse() parses KEY=VALUE,... into a QDict.  Works like
qemu_opts_parse(), except:

* Returns a QDict instead of a QemuOpts (d'oh).

* Supports nesting, unlike QemuOpts: a KEY is split into key
  fragments at '.' (dotted key convention; the block layer does
  something similar on top of QemuOpts).  The key fragments are QDict
  keys, and the last one's value is updated to VALUE.

* Each key fragment may be up to 127 bytes long.  qemu_opts_parse()
  limits the entire key to 127 bytes.

* Overlong key fragments are rejected.  qemu_opts_parse() silently
  truncates them.

* Empty key fragments are rejected.  qemu_opts_parse() happily
  accepts empty keys.

* It does not store the returned value.  qemu_opts_parse() stores it
  in the QemuOptsList.

* It does not treat parameter "id" specially.  qemu_opts_parse()
  ignores all but the first "id", and fails when its value isn't
  id_wellformed(), or duplicate (a QemuOpts with the same ID is
  already stored).  It also screws up when a value contains ",id=".

* Implied value is not supported.  qemu_opts_parse() desugars "foo" to
  "foo=on", and "nofoo" to "foo=off".

* An implied key's value can't be empty, and can't contain ','.

I intend to grow this into a saner replacement for QemuOpts.  It'll
take time, though.

Note: keyval_parse() provides no way to do lists, and its key syntax
is incompatible with the __RFQDN_ prefix convention for downstream
extensions, because it blindly splits at '.', even in __RFQDN_.  Both
issues will be addressed later in the series.
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Message-Id: <1488317230-26248-4-git-send-email-armbru@redhat.com>

Signed-off-by: NMarkus Armbruster <armbru@redhat.com>
Reviewed-by: NEric Blake <eblake@redhat.com>
Reviewed-by: NKevin Wolf <kwolf@redhat.com>
Message-Id: <1488317230-26248-3-git-send-email-armbru@redhat.com>