Commit Graph

679 Commits

Author SHA1 Message Date
Fam Zheng
8e41fb63c5 memory: Drop MemoryRegion.ram_addr
All references to mr->ram_addr are replaced by
memory_region_get_ram_addr(mr) (except for a few assertions that are
replaced with mr->ram_block).

Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1456813104-25902-5-git-send-email-famz@redhat.com>
Acked-by: Laszlo Ersek <lersek@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-03-07 13:26:29 +01:00
Eric Blake
48eb62a74f qapi: Drop useless 'data' member of unions
We started moving away from the use of the 'void *data' member
in the C union corresponding to a QAPI union back in commit
544a373; recent commits have gotten rid of other uses.  Now
that it is completely unused, we can remove the member itself
as well as the FIXME comment.  Update the testsuite to drop the
negative test union-clash-data.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1457021813-10704-11-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-05 10:42:06 +01:00
Eric Blake
4d91e9115c qapi-visit: Expose visit_type_FOO_members()
Dan Berrange reported a case where he needs to work with a
QCryptoBlockOptions union type using the OptsVisitor, but only
visit one of the branches of that type (the discriminator is not
visited directly, but learned externally).  When things were
boxed, it was easy: just visit the variant directly, which took
care of both allocating the variant and visiting its members, then
store that pointer in the union type.  But now that things are
unboxed, we need a way to visit the members without allocation,
done by exposing visit_type_FOO_members() to the user.

Before the patch, we had quite a bit of code associated with
object_members_seen to make sure that a declaration of the helper
was in scope before any use of the function.  But now that the
helper is public and declared in the header, the .c file no
longer needs to worry about topological sorting (the helper is
always in scope), which leads to some nice cleanups.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457021813-10704-4-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-05 10:41:13 +01:00
Eric Blake
c81200b014 qapi: Rename 'fields' to 'members' in generated C code
C types and JSON objects don't have fields, but members.  We
shouldn't gratuitously invent terminology.  This patch is a
strict renaming of static genarated functions, plus the naming
of the dummy filler member for empty structs, before the next
patch exposes some of that naming to the rest of the code base.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457021813-10704-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-05 10:41:09 +01:00
Eric Blake
14f00c6c49 qapi: Rename 'fields' to 'members' in generator
C types and JSON objects don't have fields, but members.  We
shouldn't gratuitously invent terminology.  This patch is a
strict renaming of generator code internals (including testsuite
comments), before later patches rename C interfaces.

No change to generated code with this patch.

Suggested-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1457021813-10704-2-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-05 10:40:52 +01:00
Daniel P. Berrange
e55250c6cb qmp-shell: fix pretty printing of JSON responses
Pretty printing of JSON responses is important to be able to understand
large responses from query commands in particular. Unfortunately this
was broken during the addition of the verbose flag in

  commit 1ceca07e48
  Author: John Snow <jsnow@redhat.com>
  Date:   Wed Apr 29 15:14:04 2015 -0400

    scripts: qmp-shell: Add verbose flag

This is because that change turned the python data structure into a
formatted JSON string before the pretty print was given it. So we're
just pretty printing a string, which is a no-op.

The original pretty printer would output python objects.

(QEMU) query-chardev
{   u'return': [   {   u'filename': u'vc',
                       u'frontend-open': False,
                       u'label': u'parallel0'},
                   {   u'filename': u'vc',
                       u'frontend-open': True,
                       u'label': u'serial0'},
                   {   u'filename': u'unix:/tmp/qemp,server',
                       u'frontend-open': True,
                       u'label': u'compat_monitor0'}]}

This fixes the problem by switching to outputting pretty formatted JSON
text instead. This has the added benefit that the pretty printed output
is now valid JSON text. Due to the way the verbose flag was handled, the
pretty printing now applies to the command sent, as well as its response:

(QEMU) query-chardev
{
    "execute": "query-chardev",
    "arguments": {}
}
{
    "return": [
        {
            "frontend-open": false,
            "label": "parallel0",
            "filename": "vc"
        },
        {
            "frontend-open": true,
            "label": "serial0",
            "filename": "vc"
        },
        {
            "frontend-open": true,
            "label": "compat_monitor0",
            "filename": "unix:/tmp/qmp,server"
        }
    ]
}

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Message-Id: <1456224706-1591-1-git-send-email-berrange@redhat.com>
Tested-by: Kashyap Chamarthy <kchamart@redhat.com>
Reviewed-by: John Snow <jsnow@redhat.com>
[Bonus fix: multiple -p now work]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-03-04 17:16:32 +01:00
Lluís Vilanova
4ade0541de trace: Add a proper API to manage auto-generated events from the 'tcg' property
Formalizes the existence of the 'event_trans' and 'event_exec' event
attributes, which until now were monkey-patched only when necessary.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 145640558759.20978.6374959404425591089.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:34:38 +00:00
Lluís Vilanova
3d211d9f4d trace: Add 'vcpu' event property to trace guest vCPU
This property identifies events that trace vCPU-specific information.

It adds a "CPUState*" argument to events with the property, identifying
the vCPU raising the event. TCG translation events also have a
"TCGv_env" implicit argument that is later used as the "CPUState*"
argument at execution time.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 145641861797.30295.6991314023181842105.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:27:10 +00:00
Lluís Vilanova
bc9beb47c7 trace: Add helper function to cast event arguments
Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 145641860680.30295.1873612736245870753.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:27:09 +00:00
Lluís Vilanova
56797b1fbc trace: Remove unnecessary intermediate event copies
The current code forces the use of a chain of ".original" dereferences,
which looks odd.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Message-id: 145641858988.30295.7223459456488075843.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:27:09 +00:00
Lluís Vilanova
3596f524d4 trace: Extend API to manage event arguments
Lets the user manage event arguments as a list, and simplifies argument
concatenation.

Signed-off-by: Lluís Vilanova <vilanova@ac.upc.edu>
Reviewed-by: Eric Blake <eblake@redhat.com>
Message-id: 145641858432.30295.3069911069472672646.stgit@localhost
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
2016-03-01 13:27:09 +00:00
Gerd Hoffmann
01df51432e qapi: rename InputAxis values.
Lowercase them.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-03-01 08:19:45 +01:00
Gerd Hoffmann
f22d0af076 qapi: rename input buttons
All lowercase, use-dash instead of CamelCase.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-03-01 08:19:07 +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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 Version: GnuPG v2
 
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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 Maydell
7bd57b5150 Queued TCG patches
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Merge remote-tracking branch 'remotes/rth/tags/pull-tcg-20160223' into staging

Queued TCG patches

# gpg: Signature made Tue 23 Feb 2016 18:27:44 GMT using RSA key ID 4DD0279B
# gpg: Good signature from "Richard Henderson <rth7680@gmail.com>"
# gpg:                 aka "Richard Henderson <rth@redhat.com>"
# gpg:                 aka "Richard Henderson <rth@twiddle.net>"

* remotes/rth/tags/pull-tcg-20160223:
  tcg: Remove unnecessary osdep.h includes from tcg-target.inc.c
  scripts/clean-includes: Ignore .inc.c files
  tcg: Rename tcg-target.c to tcg-target.inc.c
  target-sparc: Use global registers for the register window
  target-sparc: Tidy global register initialization
  tcg: Allocate indirect_base temporaries in a different order
  tcg: Implement indirect memory registers
  tcg: Work around clang bug wrt enum ranges, part 2

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-02-23 18:49:30 +00:00
Peter Maydell
f8e1f5d6a2 scripts/clean-includes: Ignore .inc.c files
Ignore files which have a .inc.c extension -- these are not headers
but they are not standalone C source files either, so we can't make
any automated decisions about what #include directives they should
have.

Reviewed-by: Eric Blake <eblake@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-Id: <1456238983-10160-3-git-send-email-peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
2016-02-23 08:30:59 -08:00
Peter Maydell
3174c64bb7 tracetool: Include osdep.h in generated-ust.c
When generating the trace/generated-ust.c source file, make sure
it includes osdep.h as its first include.

This fixes compilation with --enable-trace-backends=ust

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Message-id: 1456240661-15422-1-git-send-email-peter.maydell@linaro.org
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 15:43:30 +00:00
Peter Maydell
d57106a4b6 scripts/clean-includes: Add --all option
Add a --all option which will run the script on every C
source and header file in the repository (except for those
in a few directories which contain standalone guest code).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 12:43:05 +00:00
Peter Maydell
fd3e39a40c scripts/clean-includes: Enhance to handle header files
Enhance clean-includes to handle header files as well as .c source
files. For headers we merely remove all the redundant #include
lines, including any includes of qemu/osdep.h itself.

There is a simple mollyguard on the include file processing to
skip a few key headers like osdep.h itself, to avoid producing
bad patches if the script is run on every file in include/.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-23 12:43:05 +00:00
Fam Zheng
cf7ea1e60c scripts/kvm/kvm_stat: Fix missing right parantheses and ".format(...)"
They seem to have snuck in when applying Janosch Frank
<frankja@linux.vnet.ibm.com>'s previous patch.

Signed-off-by: Fam Zheng <famz@redhat.com>
Message-Id: <1455848416-13177-1-git-send-email-famz@redhat.com>
Reviewed-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Tested-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-22 18:40:22 +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
becceedc4d qapi: Don't box struct branch of alternate
There's no reason to do two malloc's for an alternate type visiting
a QAPI struct; let's just inline the struct directly as the C union
branch of the struct.

Surprisingly, no clients were actually using the struct member prior
to this patch outside of the testsuite; an earlier patch in the series
added some testsuite coverage to make the effect of this patch more
obvious.

In qapi.py, c_type() gains a new is_unboxed flag to control when we
are emitting a C struct unboxed within the context of an outer
struct (different from our other two modes of usage with no flags
for normal local variable declarations, and with is_param for adding
'const' in a parameter list).  I don't know if there is any more
pythonic way of collapsing the two flags into a single parameter,
as we never have a caller setting both flags at once.

Ultimately, we want to also unbox branches for QAPI unions, but as
that touches a lot more client code, it is better as separate
patches.  But since unions and alternates share gen_variants(), I
had to hack in a way to test if we are visiting an alternate type
for setting the is_unboxed flag: look for a non-object branch.
This works because alternates have at least two branches, with at
most one object branch, while unions have only object branches.
The hack will go away in a later patch.

The generated code difference to qapi-types.h is relatively small:

| struct BlockdevRef {
|     QType type;
|     union { /* union tag is @type */
|         void *data;
|-        BlockdevOptions *definition;
|+        BlockdevOptions definition;
|         char *reference;
|     } u;
| };

The corresponding spot in qapi-visit.c calls visit_type_FOO(), which
first calls visit_start_struct() to allocate or deallocate the member
and handle a layer of {} from the JSON stream, then visits the
members.  To peel off the indirection and the memory management that
comes with it, we inline this call, then suppress allocation /
deallocation by passing NULL to visit_start_struct(), and adjust the
member visit:

|     switch ((*obj)->type) {
|     case QTYPE_QDICT:
|-        visit_type_BlockdevOptions(v, name, &(*obj)->u.definition, &err);
|+        visit_start_struct(v, name, NULL, 0, &err);
|+        if (err) {
|+            break;
|+        }
|+        visit_type_BlockdevOptions_fields(v, &(*obj)->u.definition, &err);
|+        error_propagate(errp, err);
|+        err = NULL;
|+        visit_end_struct(v, &err);
|         break;
|     case QTYPE_QSTRING:
|         visit_type_str(v, name, &(*obj)->u.reference, &err);

The visit of non-object fields is unchanged.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-13-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:57 +01:00
Eric Blake
2208d64998 qapi-visit: Use common idiom in gen_visit_fields_decl()
We have several instances of methods that do an early exit if
output is not needed, then log that output is being generated,
and finally produce the output; see qapi-types.py:gen_object()
and qapi-visit.py:gen_visit_implicit_struct().  The odd man
out was gen_visit_fields_decl(); rearrange it to be more like
the others.  No semantic change or difference to generated code.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-12-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:57 +01:00
Eric Blake
1de5d4ca07 qapi: Emit structs used as variants in topological order
Right now, we emit the branches of union types as a boxed pointer,
and it suffices to have a forward declaration of the type.  However,
a future patch will swap things to directly use the branch type,
instead of hiding it behind a pointer.  For this to work, the
compiler needs the full definition of the type, not just a forward
declaration, prior to the union that is including the branch type.
This patch just adds topological sorting to hoist all types
mentioned in a branch of a union to be fully declared before the
union itself.  The sort is always possible, because we do not
allow circular union types that include themselves as a direct
branch (it is, however, still possible to include a branch type
that itself has a pointer to the union, for a type that can
indirectly recursively nest itself - that remains safe, because
that the member of the branch type will remain a pointer, and the
QMP representation of such a type adds another {} for each recurring
layer of the union type).

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-11-git-send-email-eblake@redhat.com>
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
655519030b qapi-visit: Less indirection in visit_type_Foo_fields()
We were passing 'Foo **obj' to the internal helper function, but
all uses within the helper were via reads of '*obj'.  Refactor
things to pass one less level of indirection, by having the
callers dereference before calling.

For an example of the generated code change:

|-static void visit_type_BalloonInfo_fields(Visitor *v, BalloonInfo **obj, Error **errp)
|+static void visit_type_BalloonInfo_fields(Visitor *v, BalloonInfo *obj, Error **errp)
| {
|     Error *err = NULL;
|
|-    visit_type_int(v, "actual", &(*obj)->actual, &err);
|+    visit_type_int(v, "actual", &obj->actual, &err);
|     error_propagate(errp, err);
| }
|
|@@ -261,7 +261,7 @@ void visit_type_BalloonInfo(Visitor *v,
|     if (!*obj) {
|         goto out_obj;
|     }
|-    visit_type_BalloonInfo_fields(v, obj, &err);
|+    visit_type_BalloonInfo_fields(v, *obj, &err);
| out_obj:

The refactoring will also make it easier to reuse the helpers in
a future patch when implicit structs are stored directly in the
parent struct rather than boxed through a pointer.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-9-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:57 +01:00
Markus Armbruster
59d9e84cc9 qapi-visit: Unify struct and union visit
gen_visit_union() is now just like gen_visit_struct().  Rename
it to gen_visit_object(), use it for structs, and drop
gen_visit_struct().  Output is unchanged.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1453902888-20457-4-git-send-email-armbru@redhat.com>
[split out variant handling, rebase to earlier changes]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-8-git-send-email-eblake@redhat.com>
2016-02-19 11:08:57 +01:00
Eric Blake
9a5cd424d5 qapi: Visit variants in visit_type_FOO_fields()
We initially created the static visit_type_FOO_fields() helper
function for reuse of code - we have cases where the initial
setup for a visit has different allocation (depending on whether
the fields represent a stand-alone type or are embedded as part
of a larger type), but where the actual field visits are
identical once a pointer is available.

Up until the previous patch, visit_type_FOO_fields() was only
used for structs (no variants), so it was covering every field
for each type where it was emitted.

Meanwhile, the code for visiting unions looks like:

static visit_type_U_fields() {
    visit base;
    visit local_members;
}
visit_type_U() {
    visit_start_struct();
    visit_type_U_fields();
    visit variants;
    visit_end_struct();
}

which splits the fields of the union visit across two functions.
Move the code to visit variants to live inside visit_type_U_fields(),
while making it conditional on having variants so that all other
instances of the helper function remain unchanged.  This is also
a step closer towards unifying struct and union visits, and towards
allowing one union type to be the branch of another flat union.

The resulting diff to the generated code is a bit hard to read,
but it can be verified that it touches only union types, and that
the end result is the following general structure:

static visit_type_U_fields() {
    visit base;
    visit local_members;
    visit variants;
}
visit_type_U() {
    visit_start_struct();
    visit_type_U_fields();
    visit_end_struct();
}

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-7-git-send-email-eblake@redhat.com>
[gen_visit_struct_fields() parameter variants made mandatory]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:57 +01:00
Markus Armbruster
d7445b57f4 qapi-visit: Simplify how we visit common union members
For a simple union SU, gen_visit_union() generates a visit of its
single tag member, like this:

    visit_type_SUKind(v, "type", &(*obj)->type, &err);

For a flat union FU with base B, it generates a visit of its base
fields:

    visit_type_B_fields(v, (B **)obj, &err);

Instead, we can simply visit the common members using the same fields
visit function we use for structs, generated with
gen_visit_struct_fields().  This function visits the base if any, then
the local members.

For a simple union SU, visit_type_SU_fields() contains exactly the old
tag member visit, because there is no base, and the tag member is the
only member.  For instance, the code generated for qapi-schema.json's
KeyValue changes like this:

    +static void visit_type_KeyValue_fields(Visitor *v, KeyValue **obj, Error **errp)
    +{
    +    Error *err = NULL;
    +
    +    visit_type_KeyValueKind(v, "type", &(*obj)->type, &err);
    +    if (err) {
    +        goto out;
    +    }
    +
    +out:
    +    error_propagate(errp, err);
    +}
    +
     void visit_type_KeyValue(Visitor *v, const char *name, KeyValue **obj, Error **errp)
     {
         Error *err = NULL;
    @@ -4863,7 +4911,7 @@ void visit_type_KeyValue(Visitor *v, con
         if (!*obj) {
             goto out_obj;
         }
    -    visit_type_KeyValueKind(v, "type", &(*obj)->type, &err);
    +    visit_type_KeyValue_fields(v, obj, &err);
         if (err) {
             goto out_obj;
         }

For a flat union FU, visit_type_FU_fields() contains exactly the old
base fields visit, because there is a base, but no members.  For
instance, the code generated for qapi-schema.json's CpuInfo changes
like this:

     static void visit_type_CpuInfoBase_fields(Visitor *v, CpuInfoBase **obj, Error **errp);

    +static void visit_type_CpuInfo_fields(Visitor *v, CpuInfo **obj, Error **errp)
    +{
    +    Error *err = NULL;
    +
    +    visit_type_CpuInfoBase_fields(v, (CpuInfoBase **)obj, &err);
    +    if (err) {
    +        goto out;
    +    }
    +
    +out:
    +    error_propagate(errp, err);
    +}
    +
     static void visit_type_CpuInfoX86_fields(Visitor *v, CpuInfoX86 **obj, Error **errp)
...
    @@ -3485,7 +3509,7 @@ void visit_type_CpuInfo(Visitor *v, cons
         if (!*obj) {
             goto out_obj;
         }
    -    visit_type_CpuInfoBase_fields(v, (CpuInfoBase **)obj, &err);
    +    visit_type_CpuInfo_fields(v, obj, &err);
         if (err) {
             goto out_obj;
         }

As you see, the generated code grows a bit, but in practice, it's lost
in the noise: qapi-schema.json's qapi-visit.c gains roughly 1%.

This simplification became possible with commit 441cbac "qapi-visit:
Convert to QAPISchemaVisitor, fixing bugs".  It's a step towards
unifying gen_struct() and gen_union().

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1453902888-20457-2-git-send-email-armbru@redhat.com>
[improve commit message examples]
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-6-git-send-email-eblake@redhat.com>
[Commit message tweaked]
2016-02-19 11:08:57 +01:00
Eric Blake
46534309e6 qapi: Forbid 'any' inside an alternate
The whole point of an alternate is to allow some type-safety while
still accepting more than one JSON type.  Meanwhile, the 'any'
type exists to bypass type-safety altogether.  The two are
incompatible: you can't accept every type, and still tell which
branch of the alternate to use for the parse; fix this to give a
sane error instead of a Python stack trace.

Note that other types that can't be alternate members are caught
earlier, by check_type().

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-4-git-send-email-eblake@redhat.com>
[Commit message tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:56 +01:00
Eric Blake
02a57ae32b qapi: Forbid empty unions and useless alternates
Empty unions serve no purpose, and while we compile with gcc
which permits them, strict C99 forbids them.  We happen to inject
a dummy 'void *data' member into the C unions that represent QAPI
unions and alternates, but we want to get rid of that member (it
pollutes the namespace for no good reason), which would leave us
with an empty union if the user didn't provide any branches.  While
empty structs make sense in QAPI, empty unions don't add any
expressiveness to the QMP language.  So prohibit them at parse
time.  Update the documentation and testsuite to match.

Note that the documentation already mentioned that alternates
should have "two or more JSON data types"; so this also fixes
the code to enforce that.  However, we have existing uses of a
union type with only one branch, so the 2-or-more strictness
is intentionally limited to alternates.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455778109-6278-3-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:56 +01:00
Eric Blake
9d3524b39e qapi-visit: Honor prefix of discriminator enum
When we added support for a user-specified prefix for an enum
type (commit 351d36e), we forgot to teach the qapi-visit code
to honor that prefix in the case of using a prefixed enum as
the discriminator for a flat union.  While there is still some
on-list debate on whether we want to keep prefixes, we should
at least make it work as long as it is still part of the code
base.

Reported-by: Daniel P. Berrange <berrange@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1455665965-27638-1-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-19 11:08:56 +01:00
Peter Maydell
3fc63c3f33 * Coverity fixes for IPMI and mptsas
* qemu-char fixes from Daniel and Marc-André
 * Bug fixes that break qemu-iotests
 * Changes to fix reset from panicked state
 * checkpatch false positives for designated initializers
 * TLS support in the NBD servers and clients
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Merge remote-tracking branch 'remotes/bonzini/tags/for-upstream' into staging

* Coverity fixes for IPMI and mptsas
* qemu-char fixes from Daniel and Marc-André
* Bug fixes that break qemu-iotests
* Changes to fix reset from panicked state
* checkpatch false positives for designated initializers
* TLS support in the NBD servers and clients

# gpg: Signature made Tue 16 Feb 2016 16:27:17 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: (28 commits)
  nbd: enable use of TLS with nbd-server-start command
  nbd: enable use of TLS with qemu-nbd server
  nbd: enable use of TLS with NBD block driver
  nbd: implement TLS support in the protocol negotiation
  nbd: use "" as a default export name if none provided
  nbd: always query export list in fixed new style protocol
  nbd: allow setting of an export name for qemu-nbd server
  nbd: make client request fixed new style if advertised
  nbd: make server compliant with fixed newstyle spec
  nbd: invert client logic for negotiating protocol version
  nbd: convert to using I/O channels for actual socket I/O
  nbd: convert blockdev NBD server to use I/O channels for connection setup
  nbd: convert qemu-nbd server to use I/O channels for connection setup
  nbd: convert block client to use I/O channels for connection setup
  qemu-nbd: add support for --object command line arg
  qom: add helpers for UserCreatable object types
  ipmi: sensor number should not exceed MAX_SENSORS
  mptsas: fix wrong formula
  mptsas: fix memory leak
  mptsas: add missing va_end
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
2016-02-16 17:31:56 +00:00
Peter Maydell
2aef8c9134 scripts/tracetool: Include qemu/osdep.h in generated .c files
Include qemu/osdep.h as the first include in generated .c files,
so they don't implicitly rely on some other included header
to pull it in.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-16 14:29:27 +00:00
Peter Maydell
253785e3b9 scripts/feature_to_c.sh: Include qemu/osdep.h rather than config.h
In the .c files generated by this script, include qemu/osdep.h
as the first included header, not config.h.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-16 14:29:27 +00:00
Eric Blake
9167ebd98f qapi: Clean up includes in generated files
As a followup to commit cbf2115, clean up the includes in files
generated by QAPI so that osdep.h is included first in .c files,
and headers which it implies are not included manually.  This
patch is done manually, since Coccinelle (and therefore
scripts/clean-includes) doesn't see into the generator scripts.

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Eric Blake <eblake@redhat.com>
2016-02-16 14:29:27 +00:00
Leonid Bloch
8800cf0a33 checkpatch: Eliminate false positive in case of space before square bracket in a definition
Now, macro definition such as "#define abc(x) [x] = y" should pass
without an error.

Signed-off-by: Leonid Bloch <leonid@daynix.com>
Message-Id: <1446112118-12376-3-git-send-email-leonid@daynix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-15 20:02:09 +01:00
Leonid Bloch
409db6eb71 checkpatch: Eliminate false positive in case of comma-space-square bracket
Previously, an error was printed in cases such as:
{ [1] = 5, [2] = 6 }
The space passed OK after a curly brace, but not after a comma.
Now, a space before a square bracket is allowed, if a comma comes before
it.

Signed-off-by: Leonid Bloch <leonid@daynix.com>
Message-Id: <1446112118-12376-2-git-send-email-leonid@daynix.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-15 20:02:09 +01:00
Paolo Bonzini
4db84796e7 get_maintainer.pl: fall back to git if only lists are found
It's not 100% obvious to project newcomers that all patches should be sent
there; checkpatch doesn't say so, and since it mentions other lists to CC,
the wording "the list" from the SubmitAPatch wiki page can be taken
to mean only those lists, not the main list too.  We would like therefore
to add a catch-all entry for qemu-devel@nongnu.org.

On its own, this would break fallback to git, because now every file
has a maintainer of sorts.  Modify get_maintainer.pl so that mailing
lists (L: lines) no longer prevent the fallback, only humans (M:
entries).

Several pre-existing entries have a list but no human.  These now
fall back to git.  That's a feature.

Cc: Paolo Bonzini <pbonzini@redhat.com>
Cc: Markus Armbruster <armbru@redhat.com>
Cc: John Snow <jsnow@redhat.com>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Message-Id: <1454987065-12961-1-git-send-email-swarren@wwwdotorg.org>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-09 17:07:55 +01:00
Janosch Frank
e3dd68df52 scripts/kvm/kvm_stat: Fix tracefs access checking
On kernels build without CONFIG_TRACING kvm_stat will bail out even
when traces are not used. This is not very helpful, especially if the
user can't install a new kernel. Instead, we should warn the user and
fall back to debugfs statistics.

These changes check if trace statistics were selected without kernel
support, warn with a small timeout, set the debugfs statistics option
to True and the tracefs one to False.

Fixes: 7aa4ee5 ('scripts/kvm/kvm_stat: Improve debugfs access checking')
Signed-off-by: Janosch Frank <frankja@linux.vnet.ibm.com>
Message-Id: <1454485291-43849-2-git-send-email-frankja@linux.vnet.ibm.com>
[Exit if -t is passed explicitly. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
2016-02-09 15:45:26 +01:00
Eric Blake
86ae191163 qapi: Fix compilation failure on MIPS and SPARC
Commit 86f4b687 broke compilation on MIPS and SPARC, which have a
preprocessor pollution of '#define mips 1' and '#define sparc 1',
respectively.  Treat it the same way as we do for the pollution with
'unix', so that QMP remains backwards compatible and only the C code
needs to use the alternative 'q_mips', 'q_sparc' spelling.

CC: James Hogan <james.hogan@imgtec.com>
CC: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Eric Blake <eblake@redhat.com>
Tested-by: James Hogan <james.hogan@imgtec.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
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
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
395a233f7c qapi: Don't cast Enum* to int*
C compilers are allowed to represent enums as a smaller type
than int, if all enum values fit in the smaller type.  There
are even compiler flags that force the use of this smaller
representation, although using them changes the ABI of a
binary. Therefore, our generated code for visit_type_ENUM()
(for all qapi enums) was wrong for casting Enum* to int* when
calling visit_type_enum().

It appears that no one has been using compiler ABI switches
for qemu, because if they had, we are potentially dereferencing
beyond bounds or even risking a SIGBUS on platforms where
unaligned pointer dereferencing is fatal.  But it is still
better to avoid the practice entirely, and just use the correct
types.

This matches the fix for alternate qapi types, done earlier in
commit 0426d53 "qapi: Simplify visiting of alternate types",
with generated code changing as:

| void visit_type_QType(Visitor *v, QType *obj, const char *name, Error **errp)
| {
|-    visit_type_enum(v, (int *)obj, QType_lookup, "QType", name, errp);
|+    int value = *obj;
|+    visit_type_enum(v, &value, QType_lookup, "QType", name, errp);
|+    *obj = value;
| }

Signed-off-by: Eric Blake <eblake@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Message-Id: <1454075341-13658-17-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
92b09babc1 qapi: Track all failures between visit_start/stop
Inside the generated code between visit_start_struct() and
visit_end_struct(), we were blindly setting the error into
the caller's errp parameter.  But a future patch to split
visit_end_struct() will require that we take action based
on whether an error has occurred, which requires us to track
all actions through a local err.  Rewrite the visits to be
more in line with the other generated calls.

Generated code changes look like:

|     visit_start_struct(v, (void **)obj, "Abort", name, sizeof(Abort), &err);
|-    if (!err) {
|-        if (*obj) {
|-            visit_type_Abort_fields(v, obj, errp);
|-        }
|-        visit_end_struct(v, &err);
|+    if (err) {
|+        goto out;
|     }
|+    if (!*obj) {
|+        goto out_obj;
|+    }
|+    visit_type_Abort_fields(v, obj, &err);
|+    error_propagate(errp, err);
|+    err = NULL;
|+out_obj:
|+    visit_end_struct(v, &err);
|+out:
|     error_propagate(errp, err);
| }

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-12-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:55 +01:00
Eric Blake
a16e3e5c58 qapi: Improve generated event use of qapi visitor
All other successful clients of visit_start_struct() were paired
with an unconditional visit_end_struct(); but the generated
code for events was relying on qmp_output_visitor_cleanup() to
work on an incomplete visit.  Alter the code to guarantee that
the struct is completed, which will make a future patch to
split visit_end_struct() easier to reason about.  While at it,
drop some assertions and comments that are not present in other
uses of the qmp output visitor, and pass NULL rather than "" as
the 'kind' parameter (matching most other uses where obj is NULL).

The changes to the generated code look like:

|     qmp = qmp_event_build_dict("DEVICE_TRAY_MOVED");
|
|     qov = qmp_output_visitor_new();
|-    g_assert(qov);
|-
|     v = qmp_output_get_visitor(qov);
|-    g_assert(v);
|
|-    /* Fake visit, as if all members are under a structure */
|-    visit_start_struct(v, NULL, "", "DEVICE_TRAY_MOVED", 0, &err);
|+    visit_start_struct(v, NULL, NULL, "DEVICE_TRAY_MOVED", 0, &err);
|     if (err) {
|         goto out;
|     }
|     visit_type_str(v, (char **)&device, "device", &err);
|     if (err) {
|-        goto out;
|+        goto out_obj;
|     }
|     visit_type_bool(v, &tray_open, "tray-open", &err);
|     if (err) {
|-        goto out;
|+        goto out_obj;
|     }
|-    visit_end_struct(v, &err);
|+out_obj:
|+    visit_end_struct(v, err ? NULL : &err);
|     if (err) {
|         goto out;
|     }
|
|     obj = qmp_output_get_qobject(qov);
|-    g_assert(obj != NULL);
|+    g_assert(obj);
|
|     qdict_put_obj(qmp, "data", obj);
|     emit(QAPI_EVENT_DEVICE_TRAY_MOVED, qmp, &err);

Note that the 'goto out_obj' with no intervening code before the
label, as well as the construct of 'err ? NULL : &err', are both
a bit unusual but also temporary; they get fixed in a later patch
that splits visit_end_struct() to drop its errp parameter by moving
some checking before the label.  But until that time, this was the
simplest way to avoid the appearance of passing a possibly-set
error to visit_end_struct(), even though actual code inspection
shows that visit_end_struct() for a QMP output visitor will never
set an error.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-11-git-send-email-eblake@redhat.com>
[Commit message's code diff tweaked]
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:55 +01:00
Eric Blake
e408311546 qapi: Drop dead parameter in gen_params()
Commit 5cdc8831 reworked gen_params() to be simpler, but forgot
to clean up a now-unused errp named argument.

No change to generated code.

Reported-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <1454075341-13658-6-git-send-email-eblake@redhat.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
2016-02-08 17:29:55 +01:00