Commit Graph

266 Commits

Author SHA1 Message Date
Eric Blake 983f52d4b3 qapi-visit: Add visitor.type classification
We have three classes of QAPI visitors: input, output, and dealloc.
Currently, all implementations of these visitors have one thing in
common based on their visitor type: the implementation used for the
visit_type_enum() callback.  But since we plan to add more such
common behavior, in relation to documenting and further refining
the semantics, it makes more sense to have the visitor
implementations advertise which class they belong to, so the common
qapi-visit-core code can use that information in multiple places.

A later patch will better document the types of visitors directly
in visitor.h.

For this patch, knowing the class of a visitor implementation lets
us make input_type_enum() and output_type_enum() become static
functions, by replacing the callback function Visitor.type_enum()
with the simpler enum member Visitor.type.  Share a common
assertion in qapi-visit-core as part of the refactoring.

Move comments in opts-visitor.c to match the refactored layout.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-2-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-05-12 09:47:54 +02:00
Eric Blake 0a40bdab0d qapi: Don't pass NULL to printf in string input visitor
Make sure the error message for visit_type_uint64() gracefully
handles a NULL 'name' when called from the top level or a list
context, as not all the world behaves like glibc in allowing
NULL through a printf-family %s.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1461879932-9020-21-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-04-29 11:11:36 +02:00
Daniel P. Berrange 78368575a6 block: add generic full disk encryption driver
Add a block driver that is capable of supporting any full disk
encryption format. This utilizes the previously added block
encryption code, and at this time supports the LUKS format.

The driver code is capable of supporting any format supported
by the QCryptoBlock module, so it registers one block driver
for each format. This patch only registers the "luks" driver
since the "qcow" driver is there only for back-compatibility
with existing qcow built-in encryption.

New LUKS compatible volumes can be formatted using qemu-img
with defaults for all settings.

$ qemu-img create --object secret,data=123456,id=sec0 \
      -f luks -o key-secret=sec0 demo.luks 10G

Alternatively the cryptographic settings can be explicitly
set

$ qemu-img create --object secret,data=123456,id=sec0 \
      -f luks -o key-secret=sec0,cipher-alg=aes-256,\
                 cipher-mode=cbc,ivgen-alg=plain64,hash-alg=sha256 \
      demo.luks 10G

And query its size

$ qemu-img info demo.img
image: demo.img
file format: luks
virtual size: 10G (10737418240 bytes)
disk size: 132K
encrypted: yes

Note that it was not necessary to provide the password
when querying info for the volume. The password is only
required when performing I/O on the volume

All volumes created by this new 'luks' driver should be
capable of being opened by the kernel dm-crypt driver.

The only algorithms listed in the LUKS spec that are
not currently supported by this impl are sha512 and
ripemd160 hashes and cast6 cipher.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
[ kwolf - Added #include to resolve conflict with da34e65c ]
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-30 12:11:26 +02:00
Kevin Wolf aaa436f998 block: Remove cache.writeback from blockdev-add
The WCE bit is a frontend property and should not be part of the backend
configuration. This is especially important because the same BDS can be
used by different users with different WCE requirements.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-30 11:59:32 +02:00
Veronia Bahaa f348b6d1a5 util: move declarations out of qemu-common.h
Move declarations out of qemu-common.h for functions declared in
utils/ files: e.g. include/qemu/path.h for utils/path.c.
Move inline functions out of qemu-common.h and into new files (e.g.
include/qemu/bcd.h)

Signed-off-by: Veronia Bahaa <veroniabahaa@gmail.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:17 +01:00
Markus Armbruster da34e65cb4 include/qemu/osdep.h: Don't include qapi/error.h
Commit 57cb38b included qapi/error.h into qemu/osdep.h to get the
Error typedef.  Since then, we've moved to include qemu/osdep.h
everywhere.  Its file comment explains: "To avoid getting into
possible circular include dependencies, this file should not include
any other QEMU headers, with the exceptions of config-host.h,
compiler.h, os-posix.h and os-win32.h, all of which are doing a
similar job to this file and are under similar constraints."
qapi/error.h doesn't do a similar job, and it doesn't adhere to
similar constraints: it includes qapi-types.h.  That's in excess of
100KiB of crap most .c files don't actually need.

Add the typedef to qemu/typedefs.h, and include that instead of
qapi/error.h.  Include qapi/error.h in .c files that need it and don't
get it now.  Include qapi-types.h in qom/object.h for uint16List.

Update scripts/clean-includes accordingly.  Update it further to match
reality: replace config.h by config-target.h, add sysemu/os-posix.h,
sysemu/os-win32.h.  Update the list of includes in the qemu/osdep.h
comment quoted above similarly.

This reduces the number of objects depending on qapi/error.h from "all
of them" to less than a third.  Unfortunately, the number depending on
qapi-types.h shrinks only a little.  More work is needed for that one.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
[Fix compilation without the spice devel packages. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-22 22:20:15 +01:00
Peter Maydell 4829e0378d QAPI patches for 2016-03-18
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Merge remote-tracking branch 'remotes/armbru/tags/pull-qapi-2016-03-18' into staging

QAPI patches for 2016-03-18

# gpg: Signature made Fri 18 Mar 2016 09:54:57 GMT using RSA key ID EB918653
# gpg: Good signature from "Markus Armbruster <armbru@redhat.com>"
# gpg:                 aka "Markus Armbruster <armbru@pond.sub.org>"

* remotes/armbru/tags/pull-qapi-2016-03-18:
  qapi: Use anonymous bases in QMP flat unions
  qapi: Allow anonymous base for flat union
  qapi: Make BlockdevOptions doc example closer to reality
  qapi: Don't special-case simple union wrappers
  qapi: Drop unused c_null()
  qapi: Inline gen_visit_members() into lone caller
  qapi-commands: Inline single-use helpers of gen_marshal()
  qapi-commands: Utilize implicit struct visits
  qapi-event: Utilize implicit struct visits
  qapi-event: Drop qmp_output_get_qobject() null check
  qapi: Emit implicit structs in generated C
  qapi: Adjust names of implicit types
  qapi: Make c_type() more OO-like
  qapi: Fix command with named empty argument type
  qapi: Assert in places where variants are not handled

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-03-18 17:18:41 +00:00
Eric Blake 3666a97f78 qapi: Use anonymous bases in QMP flat unions
Now that the generator supports it, we might as well use an
anonymous base rather than breaking out a single-use Base
structure, for all three of our current QMP flat unions.

Oddly enough, this change does not affect the resulting
introspection output (because we already inline the members of
a base type into an object, and had no independent use of the
base type reachable from a command).

The case_whitelist now has to list the name of an implicit
type; which is not too bad (consider it a feature if it makes
it harder for developers to make the whitelist grow :)

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1458254921-17042-16-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-18 10:29:26 +01:00
Daniel P. Berrange 3e308f20ed crypto: implement the LUKS block encryption format
Provide a block encryption implementation that follows the
LUKS/dm-crypt specification.

This supports all combinations of hash, cipher algorithm,
cipher mode and iv generator that are implemented by the
current crypto layer.

There is support for opening existing volumes formatted
by dm-crypt, and for formatting new volumes. In the latter
case it will only use key slot 0.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 16:50:40 +00:00
Daniel P. Berrange 7d9690148a crypto: add block encryption framework
Add a generic framework for supporting different block encryption
formats. Upon instantiating a QCryptoBlock object, it will read
the encryption header and extract the encryption keys. It is
then possible to call methods to encrypt/decrypt data buffers.

There is also a mode whereby it will create/initialize a new
encryption header on a previously unformatted volume.

The initial framework comes with support for the legacy QCow
AES based encryption. This enables code in the QCow driver to
be consolidated later.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 14:41:15 +00:00
Daniel P. Berrange eaec903c5b crypto: wire up XTS mode for cipher APIs
Introduce 'XTS' as a permitted mode for the cipher APIs.
With XTS the key provided must be twice the size of the
key normally required for any given algorithm. This is
because the key will be split into two pieces for use
in XTS mode.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 14:41:15 +00:00
Daniel P. Berrange 50f6753e27 crypto: add support for the twofish cipher algorithm
New cipher algorithms 'twofish-128', 'twofish-192' and
'twofish-256' are defined for the Twofish algorithm.
The gcrypt backend does not support 'twofish-192'.

The nettle and gcrypt cipher backends are updated to
support the new cipher and a test vector added to the
cipher test suite. The new algorithm is enabled in the
LUKS block encryption driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 14:41:15 +00:00
Daniel P. Berrange 94318522ed crypto: add support for the serpent cipher algorithm
New cipher algorithms 'serpent-128', 'serpent-192' and
'serpent-256' are defined for the Serpent algorithm.

The nettle and gcrypt cipher backends are updated to
support the new cipher and a test vector added to the
cipher test suite. The new algorithm is enabled in the
LUKS block encryption driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 14:41:15 +00:00
Daniel P. Berrange 084a85eedd crypto: add support for the cast5-128 cipher algorithm
A new cipher algorithm 'cast-5-128' is defined for the
Cast-5 algorithm with 128 bit key size. Smaller key sizes
are supported by Cast-5, but nothing in QEMU should use
them, so only 128 bit keys are permitted.

The nettle and gcrypt cipher backends are updated to
support the new cipher and a test vector added to the
cipher test suite. The new algorithm is enabled in the
LUKS block encryption driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 14:41:15 +00:00
Daniel P. Berrange cb730894ae crypto: add support for generating initialization vectors
There are a number of different algorithms that can be used
to generate initialization vectors for disk encryption. This
introduces a simple internal QCryptoBlockIV object to provide
a consistent internal API to the different algorithms. The
initially implemented algorithms are 'plain', 'plain64' and
'essiv', each matching the same named algorithm provided
by the Linux kernel dm-crypt driver.

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2016-03-17 14:41:14 +00:00
Changlong Xie 0ae053b7e1 qmp event: Refactor QUORUM_REPORT_BAD
Introduce QuorumOpType, and make QUORUM_REPORT_BAD compatible
with it.

Cc: Dr. David Alan Gilbert <dgilbert@redhat.com>
Cc: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Wen Congyang <wency@cn.fujitsu.com>
Signed-off-by: Changlong Xie <xiecl.fnst@cn.fujitsu.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-03-14 16:46:43 +01:00
Peter Maydell 586fc27e6a * Asynchronous dump-guest-memory from Peter
* improved logging with -D -daemonize from Dimitris
 * more address_space_* optimization from Gonglei
 * TCG xsave/xrstor thinko fix
 * chardev bugfix and documentation patch
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* Asynchronous dump-guest-memory from Peter
* improved logging with -D -daemonize from Dimitris
* more address_space_* optimization from Gonglei
* TCG xsave/xrstor thinko fix
* chardev bugfix and documentation patch

# gpg: Signature made Thu 25 Feb 2016 15:12:27 GMT using RSA key ID 78C7AE83
# gpg: Good signature from "Paolo Bonzini <bonzini@gnu.org>"
# gpg:                 aka "Paolo Bonzini <pbonzini@redhat.com>"

* remotes/bonzini/tags/for-upstream:
  target-i386: fix confusion in xcr0 bit position vs. mask
  chardev: Properly initialize ChardevCommon components
  memory: Remove unreachable return statement
  memory: optimize qemu_get_ram_ptr and qemu_ram_ptr_length
  exec: store RAMBlock pointer into memory region
  log: Redirect stderr to logfile if deamonized
  dump-guest-memory: add qmp event DUMP_COMPLETED
  Dump: add hmp command "info dump"
  Dump: add qmp command "query-dump"
  DumpState: adding total_size and written_size fields
  dump-guest-memory: add "detach" support
  dump-guest-memory: disable dump when in INMIGRATE state
  dump-guest-memory: introduce dump_process() helper function.
  dump-guest-memory: add dump_in_progress() helper function
  dump-guest-memory: using static DumpState, add DumpStatus
  dump-guest-memory: add "detach" flag for QMP/HMP interfaces.
  dump-guest-memory: cleanup: removing dump_{error|cleanup}().
  scripts/kvm/kvm_stat: Fix missing right parantheses and ".format(...)"
  qemu-options.hx: Improve documentation of chardev multiplexing mode

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-02-25 15:30:57 +00:00
Peter Xu d42a0d1484 dump-guest-memory: add qmp event DUMP_COMPLETED
One new QMP event DUMP_COMPLETED is added. When a dump finishes, one
DUMP_COMPLETED event will occur to notify the user.

Signed-off-by: Peter Xu <peterx@redhat.com>
Reviewed-by:   Fam Zheng <famz@redhat.com>
Message-Id: <1455772616-8668-12-git-send-email-peterx@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:29 +01:00
Alberto Garcia f5a845fdb4 qapi: Correct the name of the iops_rd parameter
Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-02-22 14:08:06 +01:00
Alberto Garcia 398befdf50 qapi: Add burst length fields to BlockDeviceInfo
This patch adds the new bps_*_max_length and iops_*_max_length
parameters to the BlockDeviceInfo struct.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-02-22 14:08:06 +01:00
Alberto Garcia dce13204a0 qapi: Add burst length parameters to block_set_io_throttle
This patch adds the new bps_*_max_length and iops_*_max_length
parameters to the block_set_io_throttle command.

Signed-off-by: Alberto Garcia <berto@igalia.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
2016-02-22 14:08:06 +01:00
Eric Blake dbf1192262 qapi: Change visit_start_implicit_struct to visit_start_alternate
After recent changes, the only remaining use of
visit_start_implicit_struct() is for allocating the space needed
when visiting an alternate.  Since the term 'implicit struct' is
hard to explain, rename the function to its current usage.  While
at it, we can merge the functionality of visit_get_next_type()
into the same function, making it more like visit_start_struct().

Generated code is now slightly smaller:

| {
|     Error *err = NULL;
|
|-    visit_start_implicit_struct(v, (void**) obj, sizeof(BlockdevRef), &err);
|+    visit_start_alternate(v, name, (GenericAlternate **)obj, sizeof(**obj),
|+                          true, &err);
|     if (err) {
|         goto out;
|     }
|-    visit_get_next_type(v, name, &(*obj)->type, true, &err);
|-    if (err) {
|-        goto out_obj;
|-    }
|     switch ((*obj)->type) {
|     case QTYPE_QDICT:
|         visit_start_struct(v, name, NULL, 0, &err);
...
|     }
|-out_obj:
|-    visit_end_implicit_struct(v);
|+    visit_end_alternate(v);
| out:
|     error_propagate(errp, err);
| }

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-16-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:57 +01:00
Eric Blake 544a373159 qapi: Don't box branches of flat unions
There's no reason to do two malloc's for a flat union; let's just
inline the branch struct directly into the C union branch of the
flat union.

Surprisingly, fewer clients were actually using explicit references
to the branch types in comparison to the number of flat unions
thus modified.

This lets us reduce the hack in qapi-types:gen_variants() added in
the previous patch; we no longer need to distinguish between
alternates and flat unions.

The change to unboxed structs means that u.data (added in commit
cee2dedb) is now coincident with random fields of each branch of
the flat union, whereas beforehand it was only coincident with
pointers (since all branches of a flat union have to be objects).
Note that this was already the case for simple unions - but there
we got lucky.  Remember, visit_start_union() blindly returns true
for all visitors except for the dealloc visitor, where it returns
the value !!obj->u.data, and that this result then controls
whether to proceed with the visit to the variant.  Pre-patch,
this meant that flat unions were testing whether the boxed pointer
was still NULL, and thereby skipping visit_end_implicit_struct()
and avoiding a NULL dereference if the pointer had not been
allocated.  The same was true for simple unions where the current
branch had pointer type, except there we bypassed visit_type_FOO().
But for simple unions where the current branch had scalar type, the
contents of that scalar meant that the decision to call
visit_type_FOO() was data-dependent - the reason we got lucky there
is that visit_type_FOO() for all scalar types in the dealloc visitor
is a no-op (only the pointer variants had anything to free), so it
did not matter whether the dealloc visit was skipped.  But with this
patch, we would risk leaking memory if we could skip a call to
visit_type_FOO_fields() based solely on a data-dependent decision.

But notice: in the dealloc visitor, visit_type_FOO() already handles
a NULL obj - it was only the visit_type_implicit_FOO() that was
failing to check for NULL. And now that we have refactored things to
have the branch be part of the parent struct, we no longer have a
separate pointer that can be NULL in the first place.  So we can just
delete the call to visit_start_union() altogether, and blindly visit
the branch type; there is no change in behavior except to the dealloc
visitor, where we now unconditionally visit the branch, but where that
visit is now always safe (for a flat union, we can no longer
dereference NULL, and for a simple union, visit_type_FOO() was already
safely handling NULL on pointer types).

Unfortunately, simple unions are not as easy to switch to unboxed
layout; because we are special-casing the hidden implicit type with
a single 'data' member, we really DO need to keep calling another
layer of visit_start_struct(), with a second malloc; although there
are some cleanups planned for simple unions in later patches.

visit_start_union() and gen_visit_implicit_struct() are now unused.
Drop them.

Note that after this patch, the only remaining use of
visit_start_implicit_struct() is for alternate types; the next patch
will do further cleanup based on that fact.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-14-git-send-email-eblake@redhat.com>
[Dead code deletion squashed in, commit message updated accordingly]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:57 +01:00
Eric Blake e65d89bf1a qapi: Adjust layout of FooList types
By sticking the next pointer first, we don't need a union with
64-bit padding for smaller types.  On 32-bit platforms, this
can reduce the size of uint8List from 16 bytes (or 12, depending
on whether 64-bit ints can tolerate 4-byte alignment) down to 8.
It has no effect on 64-bit platforms (where alignment still
dictates a 16-byte struct); but fewer anonymous unions is still
a win in my book.

It requires visit_next_list() to gain a size parameter, to know
what size element to allocate; comparable to the size parameter
of visit_start_struct().

I debated about going one step further, to allow for fewer casts,
by doing:
    typedef GenericList GenericList;
    struct GenericList {
        GenericList *next;
    };
    struct FooList {
        GenericList base;
        Foo *value;
    };
so that you convert to 'GenericList *' by '&foolist->base', and
back by 'container_of(generic, GenericList, base)' (as opposed to
the existing '(GenericList *)foolist' and '(FooList *)generic').
But doing that would require hoisting the declaration of
GenericList prior to inclusion of qapi-types.h, rather than its
current spot in visitor.h; it also makes iteration a bit more
verbose through 'foolist->base.next' instead of 'foolist->next'.

Note that for lists of objects, the 'value' payload is still
hidden behind a boxed pointer.  Someday, it would be nice to do:

struct FooList {
    FooList *next;
    Foo value;
};

for one less level of malloc for each list element.  This patch
is a step in that direction (now that 'next' is no longer at a
fixed non-zero offset within the struct, we can store more than
just a pointer's-worth of data as the value payload), but the
actual conversion would be a task for another series, as it will
touch a lot of code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-10-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:57 +01:00
Eric Blake f96493b1ab qapi: Simplify excess input reporting in input visitors
When reporting that an unvisited member remains at the end of an
input visit for a struct, we were using g_hash_table_find()
coupled with a callback function that always returns true, to
locate an arbitrary member of the hash table.  But if all we
need is an arbitrary entry, we can get that from a single-use
iterator, without needing a tautological callback function.

Technically, our cast of &(GQueue *) to (void **) is not strict
C (while void * must be able to hold all other pointers, nothing
says a void ** has to be the same width or representation as a
GQueue **).  The kosher way to write it would be the verbose:

    void *tmp;
    GQueue *any;
    if (g_hash_table_iter_next(&iter, NULL, &tmp)) {
        any = tmp;

But our code base (not to mention glib itself) already has other
cases of assuming that ALL pointers have the same width and
representation, where a compiler would have to go out of its way
to mis-compile our borderline behavior.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1455778109-6278-2-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:56 +01:00
Daniel P. Berrange ddffee3904 nbd: enable use of TLS with nbd-server-start command
This modifies the nbd-server-start QMP command so that it
is possible to request use of TLS. This is done by adding
a new optional parameter "tls-creds" which provides the ID
of a previously created QCryptoTLSCreds object instance.

TLS is only supported when using an IPv4/IPv6 socket listener.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1455129674-17255-17-git-send-email-berrange@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-16 17:17:49 +01:00
Eric Blake 455ba08afd qmp: Don't abuse stack to track qmp-output root
The previous commit documented an inconsistency in how we are
using the stack of qmp-output-visitor.  Normally, pushing a
single top-level object puts the object on the stack twice:
once as the root, and once as the current container being
appended to; but popping that struct only pops once.  However,
qmp_ouput_add() was trying to either set up the added object
as the new root (works if you parse two top-level scalars in a
row: the second replaces the first as the root) or as a member
of the current container (works as long as you have an open
container on the stack; but if you have popped the first
top-level container, it then resolves to the root and still
tries to add into that existing container).

Fix the stupidity by not tracking two separate things in the
stack.  Drop the now-useless qmp_output_first() and
qmp_output_last() while at it.

Saved for a later patch: we still are rather sloppy in that
qmp_output_get_object() can be called in the middle of a parse,
rather than requiring that a visit is complete.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-26-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:57 +01:00
Eric Blake a861564015 qmp: Fix reference-counting of qnull on empty output visit
Commit 6c2f9a15 ensured that we would not return NULL when the
caller used an output visitor but had nothing to visit. But
in doing so, it added a FIXME about a reference count leak
that could abort qemu in the (unlikely) case of SIZE_MAX such
visits (more plausible on 32-bit).  (Although that commit
suggested we might fix it in time for 2.5, we ran out of time;
fortunately, it is unlikely enough to bite that it was not
worth worrying about during the 2.5 release.)

This fixes things by documenting the internal contracts, and
explaining why the internal function can return NULL and only
the public facing interface needs to worry about qnull(),
thus avoiding over-referencing the qnull_ global object.

It does not, however, fix the stupidity of the stack mixing
up two separate pieces of information; add a FIXME to explain
that issue, which will be fixed shortly in a future patch.

Signed-off-by: Eric Blake <eblake@redhat.com>
Cc: qemu-stable@nongnu.org
Message-Id: <1454075341-13658-25-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:57 +01:00
Eric Blake 08f9541dec qapi: Drop unused error argument for list and implicit struct
No backend was setting an error when ending the visit of a list or
implicit struct, or when moving to the next list node.  Make the
callers a bit easier to follow by making this a part of the contract,
and removing the errp argument - callers can then unconditionally end
an object as part of cleanup without having to think about whether a
second error is dominated by a first, because there is no second
error.

A later patch will then tackle the larger task of splitting
visit_end_struct(), which can indeed set an error.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-24-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:57 +01:00
Eric Blake bdd8e6b5d8 qapi: Tighten qmp_input_end_list()
The only way that qmp_input_pop() will set errp is if a dictionary
was the most recent thing pushed.  Since we don't have any
push(struct)/pop(list) or push(list)/pop(struct) mismatches (such
a mismatch is a programming bug), we therefore cannot set errp
inside qmp_input_end_list().  Make this obvious by
using &error_abort.  A later patch will then remove the errp
parameter of qmp_input_pop(), but that will first require the
larger task of splitting visit_end_struct().

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-23-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:57 +01:00
Eric Blake 337283dffb qapi: Drop unused 'kind' for struct/enum visit
visit_start_struct() and visit_type_enum() had a 'kind' argument
that was usually set to either the stringized version of the
corresponding qapi type name, or to NULL (although some clients
didn't even get that right).  But nothing ever used the argument.
It's even hard to argue that it would be useful in a debugger,
as a stack backtrace also tells which type is being visited.

Therefore, drop the 'kind' argument as dead.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-22-git-send-email-eblake@redhat.com>
[Harmless rebase mistake cleaned up]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:57 +01:00
Eric Blake 0b2a0d6bb2 qapi: Swap 'name' in visit_* callbacks to match public API
As explained in the previous patches, matching argument order of
'name, &value' to JSON's "name":value makes sense.  However,
while the last two patches were easy with Coccinelle, I ended up
doing this one all by hand.  Now all the visitor callbacks match
the main interface.

The compiler is able to enforce that all clients match the changed
interface in visitor-impl.h, even where two pointers are being
swapped, because only one of the two pointers is const (if that
were not the case, then C's looseness on treating 'char *' like
'void *' would have made review a bit harder).

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-21-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:56 +01:00
Eric Blake 51e72bc1dd qapi: Swap visit_* arguments for consistent 'name' placement
JSON uses "name":value, but many of our visitor interfaces were
called with visit_type_FOO(v, &value, name, errp).  This can be
a bit confusing to have to mentally swap the parameter order to
match JSON order.  It's particularly bad for visit_start_struct(),
where the 'name' parameter is smack in the middle of the
otherwise-related group of 'obj, kind, size' parameters! It's
time to do a global swap of the parameter ordering, so that the
'name' parameter is always immediately after the Visitor argument.

Additional reason in favor of the swap: the existing include/qjson.h
prefers listing 'name' first in json_prop_*(), and I have plans to
unify that file with the qapi visitors; listing 'name' first in
qapi will minimize churn to the (admittedly few) qjson.h clients.

Later patches will then fix docs, object.h, visitor-impl.h, and
those clients to match.

Done by first patching scripts/qapi*.py by hand to make generated
files do what I want, then by running the following Coccinelle
script to affect the rest of the code base:
 $ spatch --sp-file script `git grep -l '\bvisit_' -- '**/*.[ch]'`
I then had to apply some touchups (Coccinelle insisted on TAB
indentation in visitor.h, and botched the signature of
visit_type_enum() by rewriting 'const char *const strings[]' to
the syntactically invalid 'const char*const[] strings').  The
movement of parameters is sufficient to provoke compiler errors
if any callers were missed.

    // Part 1: Swap declaration order
    @@
    type TV, TErr, TObj, T1, T2;
    identifier OBJ, ARG1, ARG2;
    @@
     void visit_start_struct
    -(TV v, TObj OBJ, T1 ARG1, const char *name, T2 ARG2, TErr errp)
    +(TV v, const char *name, TObj OBJ, T1 ARG1, T2 ARG2, TErr errp)
     { ... }

    @@
    type bool, TV, T1;
    identifier ARG1;
    @@
     bool visit_optional
    -(TV v, T1 ARG1, const char *name)
    +(TV v, const char *name, T1 ARG1)
     { ... }

    @@
    type TV, TErr, TObj, T1;
    identifier OBJ, ARG1;
    @@
     void visit_get_next_type
    -(TV v, TObj OBJ, T1 ARG1, const char *name, TErr errp)
    +(TV v, const char *name, TObj OBJ, T1 ARG1, TErr errp)
     { ... }

    @@
    type TV, TErr, TObj, T1, T2;
    identifier OBJ, ARG1, ARG2;
    @@
     void visit_type_enum
    -(TV v, TObj OBJ, T1 ARG1, T2 ARG2, const char *name, TErr errp)
    +(TV v, const char *name, TObj OBJ, T1 ARG1, T2 ARG2, TErr errp)
     { ... }

    @@
    type TV, TErr, TObj;
    identifier OBJ;
    identifier VISIT_TYPE =~ "^visit_type_";
    @@
     void VISIT_TYPE
    -(TV v, TObj OBJ, const char *name, TErr errp)
    +(TV v, const char *name, TObj OBJ, TErr errp)
     { ... }

    // Part 2: swap caller order
    @@
    expression V, NAME, OBJ, ARG1, ARG2, ERR;
    identifier VISIT_TYPE =~ "^visit_type_";
    @@
    (
    -visit_start_struct(V, OBJ, ARG1, NAME, ARG2, ERR)
    +visit_start_struct(V, NAME, OBJ, ARG1, ARG2, ERR)
    |
    -visit_optional(V, ARG1, NAME)
    +visit_optional(V, NAME, ARG1)
    |
    -visit_get_next_type(V, OBJ, ARG1, NAME, ERR)
    +visit_get_next_type(V, NAME, OBJ, ARG1, ERR)
    |
    -visit_type_enum(V, OBJ, ARG1, ARG2, NAME, ERR)
    +visit_type_enum(V, NAME, OBJ, ARG1, ARG2, ERR)
    |
    -VISIT_TYPE(V, OBJ, NAME, ERR)
    +VISIT_TYPE(V, NAME, OBJ, ERR)
    )

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-19-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:56 +01:00
Eric Blake 04e070d217 qapi: Consolidate visitor small integer callbacks
Commit 4e27e819 introduced optional visitor callbacks for all
sorts of int types, but no visitor has supplied any of the
callbacks for sizes less than 64 bits.  In other words, the
generic implementation based on using type_[u]int64() followed
by bounds-checking works just fine. In the interest of
simplicity, it's easier to make the visitor callback interface
not have to worry about the other sizes.

Adding some helper functions minimizes the boilerplate required
to correct FIXMEs added earlier with regards to questionable
reuse of errp, particularly now that we can guarantee from a
single file audit that value is unchanged if an error is set.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-16-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:55 +01:00
Eric Blake f755dea79d qapi: Make all visitors supply uint64 callbacks
Our qapi visitor contract supports multiple integer visitors,
but left the type_uint64 visitor as optional (falling back on
type_int64); which in turn can lead to awkward behavior with
numbers larger than INT64_MAX (the user has to be aware of
twos complement, and deal with negatives).

This patch does not address the disparity in handling large
values as negatives.  It merely moves the fallback from uint64
to int64 from the visitor core to the visitors, where the issue
can actually be fixed, by implementing the missing type_uint64()
callbacks on top of the respective type_int64() callbacks, and
with a FIXME comment explaining why that's wrong.

With that done, we now have a type_uint64() callback in every
driver, so we can make it mandatory from the core.  And although
the type_int64() callback can cover the entire valid range of
type_uint{8,16,32} on valid user input, using type_uint64() to
avoid mixed signedness makes more sense.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-15-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:55 +01:00
Eric Blake 4c40314a35 qapi: Prefer type_int64 over type_int in visitors
The qapi builtin type 'int' is basically shorthand for the type
'int64'.  In fact, since no visitor was providing the optional
type_int64() callback, visit_type_int64() was just always falling
back to type_int(), cementing the equivalence between the types.

However, some visitors are providing a type_uint64() callback.
For purposes of code consistency, it is nicer if all visitors
use the paired type_int64/type_uint64 names rather than the
mismatched type_int/type_uint64.  So this patch just renames
the signed int callbacks in place, dropping the type_int()
callback as redundant, and a later patch will focus on the
unsigned int callbacks.

Add some FIXMEs to questionable reuse of errp in code touched
by the rename, while at it (the reuse works as long as the
callbacks don't modify value when setting an error, but it's not
a good example to set) - a later patch will then fix those.

No change in functionality here, although further cleanups are
in the pipeline.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-14-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:55 +01:00
Eric Blake 7c91aabd89 qapi-visit: Kill unused visit_end_union()
The generated code can call visit_end_union() without having called
visit_start_union().  Example:

        if (!*obj) {
            goto out_obj;
        }
        visit_type_CpuInfoBase_fields(v, (CpuInfoBase **)obj, &err);
        if (err) {
            goto out_obj; // if we go from here...
        }
        if (!visit_start_union(v, !!(*obj)->u.data, &err) || err) {
            goto out_obj;
        }
        switch ((*obj)->arch) {
    [...]
        }
    out_obj:
        // ... then *obj is true, and ...
        error_propagate(errp, err);
        err = NULL;
        if (*obj) {
            // we end up here
            visit_end_union(v, !!(*obj)->u.data, &err);
        }
        error_propagate(errp, err);

Harmless only because no visitor implements end_union().  Clean it up
anyway, by deleting the function as useless.

Messed up since we have visit_end_union (commit cee2ded).

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1453902888-20457-3-git-send-email-armbru@redhat.com>
[expand scope of patch to delete rather than repair]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-13-git-send-email-eblake@redhat.com>
2016-02-08 17:29:55 +01:00
Eric Blake 4894b00b27 qapi: Dealloc visitor does not need a type_size()
The intent of having the visitor type_size() callback differ
from type_uint64() is to allow special handling for sizes; the
visitor core gracefully falls back to type_uint64() if there is
no need for the distinction.  Since the dealloc visitor does
nothing for any of the int visits, drop the pointless size
handler.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-5-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:54 +01:00
Eric Blake 77577cb8d6 qapi: Drop dead dealloc visitor variable
Commit 0b9d8542 added StackEntry.is_list_head, but forgot to
delete the now-unused QapiDeallocVisitor.is_list_head.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-4-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:54 +01:00
Eric Blake d7bea75d35 qapi: Avoid use of misnamed DO_UPCAST()
The macro DO_UPCAST() is incorrectly named: it converts from a
parent class to a derived class (which is a downcast).  Better,
and more consistent with some of the other qapi visitors, is
to use the container_of() macro through a to_FOO() helper.  Names
like 'to_ov()' may be a bit short, but for a static helper it
doesn't hurt too much, and matches existing practice in files
like qmp-input-visitor.c.

Our current definition of container_of() is weaker than
DO_UPCAST(), in that it does not require the derived class to
have Visitor as its first member, but this does not hurt our
usage patterns in qapi visitors.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:54 +01:00
Peter Maydell cbf2115190 qapi: Clean up includes
Clean up includes so that osdep.h is included first and headers
which it implies are not included manually.

This commit was created with scripts/clean-includes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 1454089805-5470-8-git-send-email-peter.maydell@linaro.org
2016-02-04 17:41:30 +00:00
Fam Zheng 16b0d55586 qemu-img: Make MapEntry a QAPI struct
The "flags" bit mask is expanded to two booleans, "data" and "zero";
"bs" is replaced with "filename" string.

Refactor the merge conditions in img_map() into entry_mergeable().

Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-id: 1453780743-16806-16-git-send-email-famz@redhat.com
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-02-02 17:50:48 +01:00
Max Reitz 327032ce74 block/qapi: Emit tray_open only if there is a tray
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 1454096953-31773-5-git-send-email-mreitz@redhat.com
2016-02-02 17:47:06 +01:00
Max Reitz 12c7ec87a7 blockdev: Fix 'change' for slot devices
'change' and related operations did not work when used on guest devices
featuring removable media but no actual tray, because
blk_dev_is_tray_open() always returned false for them and the
blockdev-{insert,remove}-medium commands required it to return true.

Fix this by making blockdev-{insert,remove}-medium work on tray-less
devices. Also, blockdev-{open,close}-tray are now explicitly no-ops when
invoked on such devices, and blk_dev_change_media_cb() is instead
called by blockdev-{insert,remove}-medium (for tray-less devices only).

Reported-by: Peter Maydell <peter.maydell@linaro.org>
Cc: qemu-stable <qemu-stable@nongnu.org>
Signed-off-by: Max Reitz <mreitz@redhat.com>
Reviewed-by: Alberto Garcia <berto@igalia.com>
Message-id: 1454096953-31773-3-git-send-email-mreitz@redhat.com
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-02 17:47:00 +01:00
John Snow 2da44dd0c6 fdc: add drive type qapi enum
Change the floppy drive type to a QAPI enum type, to allow us to
specify the floppy drive type from the CLI in a forthcoming patch.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: John Snow <jsnow@redhat.com>
Message-id: 1453495865-9649-4-git-send-email-jsnow@redhat.com
2016-01-25 14:35:23 -05:00
Dr. David Alan Gilbert 4addcd4fdc Migration: Emit event at start of pass
Emit an event each time we sync the dirty bitmap on the source;
this helps libvirt use postcopy by giving it a kick when it
might be a good idea to start the postcopy.

Signed-off-by: Dr. David Alan Gilbert <dgilbert@redhat.com>
Reviewed-by: Juan Quintela <quintela@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Amit Shah <amit.shah@redhat.com>
Message-Id: <1450266458-3178-5-git-send-email-dgilbert@redhat.com>
Signed-off-by: Amit Shah <amit.shah@redhat.com>
2016-01-13 16:02:13 +05:30
Fam Zheng df92562e68 qmp: Add blockdev-mirror command
This will start a mirror job from a named device to another named
device, its relation with drive-mirror is similar with blockdev-backup
to drive-backup.

In blockdev-mirror, the target node should be prepared by blockdev-add,
which will be responsible for assigning a name to the new node, so
we don't have 'node-name' parameter.

Signed-off-by: Fam Zheng <famz@redhat.com>
Acked-by: Markus Armbruster <armbru@redhat.com>
Message-id: 1450932306-13717-5-git-send-email-famz@redhat.com
Reviewed-by: Max Reitz <mreitz@redhat.com>
Signed-off-by: Max Reitz <mreitz@redhat.com>
2016-01-07 21:30:18 +01:00
Daniel P. Berrange d8c02bcc94 crypto: move QCryptoCipherAlgorithm/Mode enum definitions into QAPI
The QCryptoCipherAlgorithm and QCryptoCipherMode enums are
defined in the crypto/cipher.h header. In the future some
QAPI types will want to reference the hash enums, so move
the enum definition into QAPI too.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-23 11:02:20 +00:00
Daniel P. Berrange d84b79d358 crypto: move QCryptoHashAlgorithm enum definition into QAPI
The QCryptoHashAlgorithm enum is defined in the crypto/hash.h
header. In the future some QAPI types will want to reference
the hash enums, so move the enum definition into QAPI too.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-23 11:02:20 +00:00
Daniel P. Berrange ac1d887849 crypto: add QCryptoSecret object class for password/key handling
Introduce a new QCryptoSecret object class which will be used
for providing passwords and keys to other objects which need
sensitive credentials.

The new object can provide secret values directly as properties,
or indirectly via a file. The latter includes support for file
descriptor passing syntax on UNIX platforms. Ordinarily passing
secret values directly as properties is insecure, since they
are visible in process listings, or in log files showing the
CLI args / QMP commands. It is possible to use AES-256-CBC to
encrypt the secret values though, in which case all that is
visible is the ciphertext.  For ad hoc developer testing though,
it is fine to provide the secrets directly without encryption
so this is not explicitly forbidden.

The anticipated scenario is that libvirtd will create a random
master key per QEMU instance (eg /var/run/libvirt/qemu/$VMNAME.key)
and will use that key to encrypt all passwords it provides to
QEMU via '-object secret,....'.  This avoids the need for libvirt
(or other mgmt apps) to worry about file descriptor passing.

It also makes life easier for people who are scripting the
management of QEMU, for whom FD passing is significantly more
complex.

Providing data inline (insecure, only for ad hoc dev testing)

  $QEMU -object secret,id=sec0,data=letmein

Providing data indirectly in raw format

  printf "letmein" > mypasswd.txt
  $QEMU -object secret,id=sec0,file=mypasswd.txt

Providing data indirectly in base64 format

  $QEMU -object secret,id=sec0,file=mykey.b64,format=base64

Providing data with encryption

  $QEMU -object secret,id=master0,file=mykey.b64,format=base64 \
        -object secret,id=sec0,data=[base64 ciphertext],\
	           keyid=master0,iv=[base64 IV],format=base64

Note that 'format' here refers to the format of the ciphertext
data. The decrypted data must always be in raw byte format.

More examples are shown in the updated docs.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
2015-12-18 16:25:08 +00:00