target-arm: Split cpreg access checks out from read/write functions

Several of the system registers handled via the ARMCPRegInfo
mechanism have access trap control bits controlling whether the
registers are accessible to lower privilege levels. Replace
the existing mechanism (allowing the read and write functions
to return EXCP_UDEF if access is denied) with a dedicated
"check access rights" function pointer in the ARMCPRegInfo.
This will allow us to simplify some of the register definitions,
which no longer need read/write functions purely to handle
the access checks.

We take the opportunity to define the return value from the
access checking function in a way that allows us to set the
correct exception syndrome information for exceptions taken
to AArch64 (which may need to distinguish access failures due
to a configurable trap or enable from other kinds of access
failure).

This commit defines the new mechanism but does not move any
of the registers across to use it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
target-arm: Convert performance monitor reginfo to accessfn

Convert the performance monitor reginfo definitions to use
an accessfn rather than returning EXCP_UDEF from read and
write functions. This also allows us to fix a couple of XXX
cases where we weren't imposing the access restrictions on
RAZ/WI or constant registers.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
target-arm: Convert generic timer reginfo to accessfn

Convert the reginfo structs for the generic timer registers
to use access functions rather than returning EXCP_UDEF from
their read handlers. In some cases this allows us to remove
a read handler completely.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
target-arm: Convert miscellaneous reginfo structs to accessfn

Convert the remaining miscellaneous cases of reginfo read/write
functions returning EXCP_UDEF to use an accessfn instead:
TEEHBR, and the ATS address-translation operations.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
target-arm: Drop success/fail return from cpreg read and write functions

All cpreg read and write functions now return 0, so we can clean up
their prototypes:
 * write functions return void
 * read functions return the value rather than taking a pointer
   to write the value to

This is a fairly mechanical change which makes only the bare
minimum set of changes to the callers of read and write functions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
target-arm: Remove unnecessary code now read/write fns can't fail

Now that cpreg read and write functions can't fail and throw an
exception, we can remove the code from the translator that synchronises
the guest PC in case an exception is thrown.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
target-arm: Remove failure status return from read/write_raw_cp_reg

The read_raw_cp_reg and write_raw_cp_reg functions can now never
fail (in fact they should never have failed previously unless
there was a bug in a reginfo that meant no raw accessor was
provided for a might-trap register). This allows us to clean up
their prototypes so the write function returns void and the
read function returns the value read, which in turn lets us
simplify the callers.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
target-arm: Fix incorrect type for value argument to write_raw_cp_reg

The write_raw_cp_reg's value argument should be a uint64_t, since
that's what all its callers hand it and what all the functions it
calls take. A (harmless) typo meant we were accidentally declaring
it as int64_t.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
target-arm: A64: Implement store-exclusive for system mode

System mode store-exclusive use a different code path to usermode ones;
implement this missing code, in a similar way to the 32 bit version.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
target-arm: A64: Add opcode comments to disas_simd_three_reg_diff

The opcode switch in disas_simd_three_reg_diff() is missing the
customary comments indicating which cases correspond to which
instructions. Add them.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
target-arm: A64: Add most remaining three-reg-diff widening ops

Add the remainder of the 64x64->128 operations in the three-reg-diff
category except for PMULL, PMULL2.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
target-arm: A64: Implement the wide 3-reg-different operations

Implement the wide three-reg-different operations:
SADDW, UADDW, SSUBW and USUBW.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
target-arm: A64: Implement narrowing three-reg-diff operations

Implement the narrowing three-reg-diff operations: ADDHN,
RADDHN, SUBHN and RSUBHN.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
target-arm: A64: Implement unprivileged load/store

Implement the unprivileged load and store instructions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
linux-user: AArch64: Fix exclusive store of the zero register

Signed-off-by: Janne Grunau <j@jannau.net>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Merge remote-tracking branch 'remotes/qmp-unstable/queue/qmp' into staging

* remotes/qmp-unstable/queue/qmp:
  monitor: Add object_add class argument completion.
  monitor: Add object_del id argument completion.
  monitor: Add device_add device argument completion.
  monitor: Add device_del id argument completion.
  qmp: expose list of supported character device backends
  Use error_is_set() only when necessary
  QMP: allow JSON dict arguments in qmp-shell
  hmp: migrate command (without -d) now blocks correctly

Conflicts:
	blockdev.c

[PMM: resolved trivial conflict in blockdev.c]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
util: Split out exec_dir from os_find_datadir

With this change, main() calls qemu_init_exec_dir and uses argv[0] to
init exec_dir. The saved value can be retrieved with
qemu_get_exec_dir later. It will be reused by module loading.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
rules.mak: fix $(obj) to a real relative path

Makefile.target includes rule.mak and unnested common-obj-y, then prefix
them with '../', this will ignore object specific QEMU_CFLAGS in subdir
Makefile.objs:

    $(obj)/curl.o: QEMU_CFLAGS += $(CURL_CFLAGS)

Because $(obj) here is './block', instead of '../block'. This doesn't
hurt compiling because we basically build all .o from top Makefile,
before entering Makefile.target, but it will affact arriving per-object
libs support.

The starting point of $(obj) is passed in as argument of unnest-vars, as
well as nested variables, so that different Makefiles can pass in a
right value.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
rules.mak: allow per object cflags and libs

Adds extract-libs in LINK to expand any "per object libs", the syntax to define
such a libs options is like:

        foo.o-libs := $(CURL_LIBS)

in block/Makefile.objs.

Similarly,

        foo.o-cflags := $(FOO_CFLAGS)

is also supported.

"foo.o" must be listed in a nested var (e.g. common-obj-y) to make the
option variables effective.

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
block: use per-object cflags and libs

No longer adds flags and libs for them to global variables, instead
create config-host.mak variables like FOO_CFLAGS and FOO_LIBS, which is
used as per object cflags and libs.

This removes unwanted dependencies from libcacard.

Signed-off-by: Fam Zheng <famz@redhat.com>
[Split from Fam's patch to enable modules. - Paolo]
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

Signed-off-by: Fam Zheng <famz@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>