Commit Graph

1415 Commits

Author SHA1 Message Date
Sergey Fedorov
6a3038db7c
cpu: Add callback to check architectural watchpoint match
When QEMU watchpoint matches, that is not definitely an architectural
watchpoint match yet. If it is a stop-before-access watchpoint then that
is hardly possible to ignore it after throwing a TCG exception.

A special callback is introduced to check for architectural watchpoint
match before raising a TCG exception.

Backports commit 568496c0c0f1863a4bc18539962cd8d81baa4e30 from qemu
2018-02-20 11:43:56 -05:00
Peter Maydell
3d5b54cf4b
target-arm: Fix IL bit reported for Thumb VFP and Neon traps
All Thumb Neon and VFP instructions are 32 bits, so the IL
bit in the syndrome register should be set. Pass false to the
syn_* function's is_16bit argument rather than s->thumb
so we report the correct IL bit.

Backports commit 7d197d2db5e99e4c8b20f6771ddc7303acaa1c89 from qemu
2018-02-20 11:39:39 -05:00
Peter Maydell
5b8ad0e2fc
target-arm: Fix IL bit reported for Thumb coprocessor traps
All Thumb coprocessor instructions are 32 bits, so the IL
bit in the syndrome register should be set. Pass false to the
syn_* function's is_16bit argument rather than s->thumb
so we report the correct IL bit.

Backports commit 4df322593037d2700f72dfdfb967300b7ad2e696 from qemu
2018-02-20 11:38:27 -05:00
Peter Maydell
814bffc1ee
target-arm: Correct misleading 'is_thumb' syn_* parameter names
In syndrome register values, the IL bit indicates the instruction
length, and is 1 for 4-byte instructions and 0 for 2-byte
instructions. All A64 and A32 instructions are 4-byte, but
Thumb instructions may be either 2 or 4 bytes long. Unfortunately
we named the parameter to the syn_* functions for constructing
syndromes "is_thumb", which falsely implies that it should be
set for all Thumb instructions, rather than only the 16-bit ones.
Fix the functions to name the parameter 'is_16bit' instead.

Backports commit fc05f4a62c568b607ec3fe428a419bb38205b570 from qemu
2018-02-20 11:36:55 -05:00
Peter Maydell
a3ff1c4a65
target-arm: Enable EL3 for Cortex-A53 and Cortex-A57
Enable EL3 support for our Cortex-A53 and Cortex-A57 CPU models.
We have enough implemented now to be able to run real world code
at least to some extent (I can boot ARM Trusted Firmware to the
point where it pulls in OP-TEE and then falls over because it
doesn't have a UEFI image it can chain to).

Backports commit 3ad901bc2b98f5539af9a7d4aef140a6d8fa6442 from qemu
2018-02-20 11:31:44 -05:00
Peter Maydell
aecf7b05dc
target-arm: Implement NSACR trapping behaviour
Implement some corner cases of the behaviour of the NSACR
register on ARMv8:
* if EL3 is AArch64 then accessing the NSACR from Secure EL1
with AArch32 should trap to EL3
* if EL3 is not present or is AArch64 then reads from NS EL1 and
NS EL2 return constant 0xc00

It would in theory be possible to implement all these with
a single reginfo definition, but for clarity we use three
separate definitions for the three cases and install the
right one based on the CPU feature flags.

Backports commit 2f027fc52d4b444a47cb05a9c96697372a6b57d2 from qemu
2018-02-20 11:29:29 -05:00
Peter Maydell
6dbc781ce3
target-arm: Add isread parameter to CPAccessFns
System registers might have access requirements which need to
be described via a CPAccessFn and which differ for reads and
writes. For this to be possible we need to pass the access
function a parameter to tell it whether the access being checked
is a read or a write.

Backports commit 3f208fd76bcc91a8506681bb8472f2398fe6f487 from qemu
2018-02-20 11:24:17 -05:00
Peter Maydell
4838c1dfe9
target-arm: Update arm_generate_debug_exceptions() to handle EL2/EL3
The arm_generate_debug_exceptions() function as originally implemented
assumes no EL2 or EL3. Since we now have much more of an implementation
of those now, fix this assumption.

Backports commit 533e93f1cf12c570aab45f14663dab6fb8ea3ffc from qemu
2018-02-20 11:12:36 -05:00
Peter Maydell
4552444928
target-arm: Use access_trap_aa32s_el1() for SCR and MVBAR
The registers MVBAR and SCR should have the behaviour of trapping to
EL3 if accessed from Secure EL1, but we were incorrectly implementing
them to UNDEF (which would trap to EL1). Fix this by using the new
access_trap_aa32s_el1() access function.

Backports commit efe4a274083f61484a8f1478d93f229d43aa8095 from qemu
2018-02-20 11:10:38 -05:00
Peter Maydell
c0411e5422
target-arm: Implement MDCR_EL3 and SDCR
Implement the MDCR_EL3 register (which is SDCR for AArch32).
For the moment we implement it as reads-as-written.

Backports commit 5513c3abed8e5fabe116830c63f0d3fe1f94bd21 from qemu
2018-02-20 11:08:15 -05:00
Peter Maydell
a2fd906e8b
target-arm: Fix typo in comment in arm_is_secure_below_el3()
Fix a typo where "EL2" was written but "EL3" intended.

Backports commit 6b7f0b61f080b886c9b4bba8240379ce90e20b12 from qemu
2018-02-20 11:05:14 -05:00
Paolo Bonzini
98452daad6
target-i386: fix PSE36 mode
(pde & 0x1fe000) is a 32-bit integer; when shifting it
into bits 39-32 the result is zero. Fix it by making the
mask (and thus the result of the AND) a 64-bit integer.

Reported by Coverity.

Backports commit 388ee48a88e684e719660a2cae9c21897b94fa37 from qemu
2018-02-20 11:03:49 -05:00
Richard Henderson
65a78ebb26
target-i386: Deconstruct the cpu_T array
All references to cpu_T are done with a constant index. It aids
readability to decompose the array into two scalar variables.

Backports commit 1d1cc4d0f481b2939c7e9f6606e571b2fc81971a from qemu
2018-02-20 11:02:34 -05:00
Richard Henderson
5d45260df7
target-i386: Tidy gen_add_A0_im
Merge gen_op_addl_A0_im and gen_op_addq_A0_im into gen_add_A0_im
and clean up the ifdef.

Replace the one remaining user of gen_op_addl_A0_im with gen_add_A0_im.

Backports commit 4e85057b92d214decf10045d3d4faa2faf33d100 from qemu
2018-02-20 10:20:04 -05:00
Richard Henderson
0004dfcba3
target-i386: Rewrite leave
Unify the code across stack pointer widths. Fix the note about
not updating ESP before the potential exception.

Backports commit 2045f04c3ae030bda650f84035f114bbd84909a9 from qemu
2018-02-20 10:16:56 -05:00
Richard Henderson
7dd4fcc621
target-i386: Rewrite gen_enter inline
Use gen_lea_v_seg for centralized segment base knowledge. Unify
code across 32- and 64-bit. Fix note about "must save state"
before using the out-of-line helpers.

Backports commit 743e398e2fbf2f7183bf7a53c9d011fabcaa1770 from qemu
2018-02-20 10:13:43 -05:00
Richard Henderson
302752df8b
target-i386: Use gen_lea_v_seg in pusha/popa
More centralization of handling of segment bases.
Also fixes the note about 16-bit wrap around not fully handled.

Backports commit d37ea0c04723f3e15fde55fe97cff6278159929b from qemu
2018-02-20 10:07:46 -05:00
Richard Henderson
092c7bea97
target-i386: Access segs via TCG registers
Having segs[].base as a register significantly improves code
generation for real and protected modes, particularly for TBs
that have multiple memory references where the segment base
can be held in a hard register through the TB.

Backports commit 3558f8055f37a34762b7a2a0f02687e6eeab893d from qemu
2018-02-20 10:02:37 -05:00
Richard Henderson
969f8ab407
target-i386: Use gen_lea_v_seg in stack subroutines
I.e. gen_push_v, gen_pop_T0, gen_stack_A0.
More centralization of handling of segment bases.

Backports commit 77ebcad04f3659fa7eb799928fdd68280fac720d from qemu
2018-02-20 09:28:40 -05:00
Richard Henderson
0d1766a9f0
target-i386: Use gen_lea_v_seg in gen_lea_modrm
Centralize handling of segment bases.

Backports commit d6a2914984c89fa0a3125b9842e0cbf68de79a3d from qemu
2018-02-20 09:23:49 -05:00
Richard Henderson
f3220dbb8c
target-i386: Introduce mo_stacksize
Centralize computation of a MO_SIZE for the stack pointer.

Backports commit 64ae256c2450262e27f07657c5734d3197458d95 from qemu
2018-02-20 09:18:48 -05:00
Richard Henderson
63c4e79870
target-i386: Create gen_lea_v_seg
Add forgotten zero-extension in the TARGET_X86_64, !CODE64, ss32 case;
use this new function to implement gen_string_movl_A0_EDI,
gen_string_movl_A0_ESI, gen_add_A0_ds_seg.

Backports commit ca2f29f555805d07fb0b9ebfbbfc4e3656530977 from qemu
2018-02-20 09:17:13 -05:00
Lioncash
c658126845
include: Move RAMList to ramlist.h
Moves the struct back into qemu's headers
2018-02-20 08:47:51 -05:00
Lioncash
cdd4003ce9
Move RAMBlock to ram_addr.h
Moves it back into qemu's includes.
2018-02-20 08:35:44 -05:00
Paolo Bonzini
cbc56b3ceb
memory: add early bail out from cpu_physical_memory_set_dirty_range
This condition is true in the common case, so we can cut out the body of
the function. In addition, this makes it easier for the compiler to do
at least partial inlining, even if it decides that fully inlining the
function is unreasonable.

Backports commit 8bafcb21643a39a5b29109f8bd5ee5a6f0f6850b from qemu
2018-02-20 08:32:10 -05:00
Lioncash
a268815478
include: Add stubbed xen function
Will allow us to not comment out code all the time for xen checks (ideally)
2018-02-20 08:29:58 -05:00
Markus Armbruster
91b4e76fef
error: New error_fatal
Similar to error_abort, but doesn't report where the error was
created, and terminates the process with exit(1) rather than abort().

Backports commit a29a37b994ca3c5a1d39fa0e8934f7e0f2cf57ef from qemu
2018-02-20 08:22:27 -05:00
Markus Armbruster
c4a06e2d12
error: Improve documentation some more
Don't claim error_report_err() always reports to stderr. It actually
reports to the current monitor when we have one.

Clarify intended use of error_abort and error_fatal.

Backports commit 10303f04b98efa76e638b9ae4632688f56f088fc from qemu
2018-02-20 08:13:39 -05:00
Eric Blake
0c04f85d31
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.

Backports commit 86ae191163d48ff4ff9d9996868e6cfe92a82449 from qemu
2018-02-20 08:11:01 -05:00
Eric Blake
49b8891872
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.

Backports commit 455ba08afde784466420449d01c6458f88349d55 from qemu
2018-02-20 08:09:56 -05:00
Eric Blake
25dad6e8d5
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.

Backports commit a86156401559cb4401cf9ecc704faeab6fc8bb19 from qemu
2018-02-20 08:07:31 -05:00
Eric Blake
a2fc66a005
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().

Backports commit bdd8e6b5d8a9def83d491a3f41c10424fc366258 from qemu
2018-02-19 23:44:45 -05:00
Eric Blake
1f54314cbb
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.

Backports commit 337283dffbb5ad5860ed00408a5fd0665c21be07 from qemu
2018-02-19 23:43:54 -05:00
Eric Blake
844c136945
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).

Backports commit 0b2a0d6bb2446060944061e53e87d0c7addede79 from qemu
2018-02-19 23:36:52 -05:00
Eric Blake
4100f3b78a
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.

Backports commit 04e070d217b4414f1f91aa8ad25fc0ae7ca0be93 from qemu
2018-02-19 23:21:56 -05:00
Eric Blake
9ec25b4673
qom: Swap 'name' next to visitor in ObjectPropertyAccessor
Similar to the previous patch, it's nice to have all functions
in the tree that involve a visitor and a name for conversion to
or from QAPI to consistently stick the 'name' parameter next
to the Visitor parameter.

Done by manually changing include/qom/object.h and qom/object.c,
then running this Coccinelle script and touching up the fallout
(Coccinelle insisted on adding some trailing whitespace).

@ rule1 @
identifier fn;
typedef Object, Visitor, Error;
identifier obj, v, opaque, name, errp;
@@
void fn
- (Object *obj, Visitor *v, void *opaque, const char *name,
+ (Object *obj, Visitor *v, const char *name, void *opaque,
Error **errp) { ... }

@@
identifier rule1.fn;
expression obj, v, opaque, name, errp;
@@
fn(obj, v,
- opaque, name,
+ name, opaque,
errp)

Backports commit d7bce9999df85c56c8cb1fcffd944d51bff8ff48 from qemu
2018-02-19 23:14:37 -05:00
Eric Blake
5dd5646a9a
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)
)

Backports commit 51e72bc1dd6ace6e91d675f41a1f09bd00ab8043 from qemu
2018-02-19 22:45:07 -05:00
Eric Blake
5b6f0cbdb7
qom: Use typedef for Visitor
No need to repeat 'struct Visitor' when we already have it in
typedefs.h. Omitting the redundant 'struct' also makes a later
patch easier to search for all object property callbacks that
are associated with a Visitor.

Backports commit 4fa45492c3387c0fa51e8e81160ac9a7814f44a2 from qemu
2018-02-19 22:26:47 -05:00
Eric Blake
b978871f20
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;
| }

Backports commit 395a233f7c089f23e3c0d43ce34c709dc5acd7de from qemu
2018-02-19 22:24:19 -05:00
Eric Blake
7e83274012
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).

Backports commit 7c91aabd8964cfdf637f302c579c95401f21ce92 from qemu
2018-02-19 22:22:24 -05:00
Eric Blake
264748ad06
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);
| }

Backports commit 92b09babc11b60458c28cfe37eaa314de50e6241 from qemu
2018-02-19 22:19:40 -05:00
Eric Blake
4f513b2070
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.

Backports commit a16e3e5c5825c90887a863513916f93eeec16c55 from qemu
2018-02-19 22:18:31 -05:00
Eric Blake
b847298d08
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.

Backports commit e408311546b633b232312450d9017f4db21df0dc from qemu
2018-02-19 22:16:16 -05:00
Markus Armbruster
b2c9386111
qapi: Use Python 2.6 "except E as ..." syntax
PEP 8 calls for it, because it's forward compatible with Python 3.
Supported since Python 2.6, which we require (commit fec2103).

Backports commit 291928a80f39670929fcce222acd5e21d1434692 from qemu
2018-02-19 22:14:39 -05:00
Eric Blake
f7d5b1c833
qapi: Detect base class loops
It should be fairly obvious that qapi base classes need to
form an acyclic graph, since QMP cannot specify the same
key more than once, while base classes are included as flat
members alongside other members added by the child. But the
old check_member_clash() parser function was not prepared to
check for this, and entered an infinite recursion (at least
until Python gives up, complaining about nesting too deep).

Now that check_member_clash() has been recently removed,
attempts at self-inheritance trigger an assertion failure
introduced by commit ac88219a. The obvious fix is to turn
the assertion into a conditional.

This patch includes both the tests (base-cycle-direct and
base-cycle-indirect) and the fix, since the .err file output
for the unfixed case is not useful (particularly when it was
warning about unbounded recursion, as that limit may be
platform-specific).

We don't need to worry about cycles in flat unions (neither
the base type nor the type of a variant can be a union) nor
in alternates (alternate branches cannot themselves be an
alternate). But if we later allow a union type as a variant,
we will still be okay, as QAPISchemaObjectTypeVariants.check()
triggers the same QAPISchemaObjectType.check() that will
detect any loops.

Likewise, we need not worry about the case of diamond
inheritance where the same class is used for a flat union base
class and one of its variants; either both uses will introduce
a collision in trying to insert the same member name twice, or
the shared type is empty and changes nothing.

Backports commit bac5429ccb4f41d421ec641b11f1852c8420fdb7 from qemu
2018-02-19 22:12:19 -05:00
Eric Blake
63f288263a
qapi: Move duplicate collision checks to schema check()
With the recent commit 'qapi: Detect collisions in C member
names', we have two different locations for detecting clashes -
one at parse time, and another at QAPISchema*.check() time.
Remove all of the ad hoc parser checks, and delete associated
code (for example, the global check_member_clash() method is
no longer needed).

Testing this showed that the test union-bad-branch wasn't adding
much: union-clash-branches also exposes the error message when
branches collide, and we've recently fixed things to avoid an
implicit collision with max. Likewise, the error for
enum-clash-member changes to report our new detection of
upper case in a value name, unless we modify the test to use
all lower case.

The wording of several error messages has changed, but the
change is generally an improvement rather than a regression.

No change to generated code.

Backports commit 01cfbaa4c36ecd9f1c7bcbad50c92758e1d147c4 from qemu
2018-02-19 22:11:28 -05:00
Eric Blake
514226002a
qapi: Enforce (or whitelist) case conventions on qapi members
We document that members of enums and objects should be
'lower-case', although we were not enforcing it. We have to
whitelist a few pre-existing entities that violate the norms.
Add three new tests to expose the new error message, each of
which first uses the whitelisted name 'UuidInfo' to prove the
whitelist works, then triggers the failure (this is the same
pattern used in the existing returns-whitelist.json test).

Note that by adding this check, we have effectively forbidden
an entity with a case-insensitive clash of member names, for
any entity that is not on the whitelist (although there is
still the possibility to clash via '-' vs. '_').

Not done here: a future patch should also add naming convention
support and whitelist exceptions for command, event, and type
names.

The additions to QAPISchemaMember.check_clash() check whether
info['name'] is in the whitelist (the top-most entity name at
the point 'info' tracks), rather than self.owner (the type,
possibly implicit, that directly owns the member), because it
is easier to maintain the whitelist by the names actually in
the user's .json file, rather than worrying about the names
of implicit types.

Backports commit 893e1f2c5170d54316f1dcf3fefae679175622fc from qemu
2018-02-19 22:09:45 -05:00
Eric Blake
2e1e2c4d51
qapi: Track enum values by QAPISchemaMember, not string
Rather than using just an array of strings, make enum.values be
an array of the new QAPISchemaMember type, and add a helper
member_names() method to get back at the original list of names.
Likewise, creating an enum requires wrapping strings, via a new
QAPISchema._make_enum_members() method. The benefit of wrapping
enum members in a QAPISchemaMember Python object is that we now
share the existing code for C name clash detection (although the
code is not yet active until a later commit removes the earlier
ad hoc parser checks).

In a related change, the QAPISchemaMember._pretty_owner() method
needs to learn about one more implicit type name: the generated
enum associated with a simple union.

In the interest of keeping the changes of this patch local to one
file, the visitor interface still passes just a list of names
rather than the full list of QAPISchemaMember instances. We may
want to revisit this in the future, if the consistency with
visit_object_type() is worth it.

Backports commit 93bda4dd461358b4fc05dfd8e2d6419cdd574789 from qemu
2018-02-19 22:07:17 -05:00
Eric Blake
ff43b7446a
qapi: Prepare new QAPISchemaMember base class
We want to share some clash detection code between enum values
and object type members. To assist with that, split off part
of QAPISchemaObjectTypeMember into a new base class
QAPISchemaMember that tracks name, owner, and common clash
detection code; while the former keeps the additional fields
for type and optional flag.

Backports commit d44f9ac80c43e34b1522cde8829f0ab371f086ca from qemu
2018-02-19 22:04:41 -05:00
Eric Blake
994490d197
qapi: Shorter visits of optional fields
For less code, reflect the determined boolean value of an optional
visit back to the caller instead of making the caller read the
boolean after the fact.

The resulting generated code has the following diff:

|- visit_optional(v, &has_fdset_id, "fdset-id");
|- if (has_fdset_id) {
|+ if (visit_optional(v, &has_fdset_id, "fdset-id")) {
| visit_type_int(v, &fdset_id, "fdset-id", &err);
| if (err) {
| goto out;
| }
| }

Backports commit 29637a6ee913df8fcdf371426ee48956b945b618 from qemu
2018-02-19 22:03:23 -05:00