The qmp/hmp command 'system_wakeup' is simply a direct call to
'qemu_system_wakeup_request' from vl.c. This function verifies if
runstate is SUSPENDED and if the wake up reason is valid before
proceeding. However, no error or warning is thrown if any of those
pre-requirements isn't met. There is no way for the caller to
differentiate between a successful wakeup or an error state caused
when trying to wake up a guest that wasn't suspended.

This means that system_wakeup is silently failing, which can be
considered a bug. Adding error handling isn't an API break in this
case - applications that didn't check the result will remain broken,
the ones that check it will have a chance to deal with it.

Adding to that, the commit before previous created a new QMP API called
query-current-machine, with a new flag called wakeup-suspend-support,
that indicates if the guest has the capability of waking up from suspended
state. Although such guest will never reach SUSPENDED state and erroring
it out in this scenario would suffice, it is more informative for the user
to differentiate between a failure because the guest isn't suspended versus
a failure because the guest does not have support for wake up at all.

All this considered, this patch changes qmp_system_wakeup to check if
the guest is capable of waking up from suspend, and if it is suspended.
After this patch, this is the output of system_wakeup in a guest that
does not have wake-up from suspend support (ppc64):

(qemu) system_wakeup
wake-up from suspend is not supported by this guest
(qemu)

And this is the output of system_wakeup in a x86 guest that has the
support but isn't suspended:

(qemu) system_wakeup
Unable to wake up: guest is not in suspended state
(qemu)
Reported-by: NBalamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20181205194701.17836-4-danielhb413@gmail.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Acked-by: NEduardo Habkost <ehabkost@redhat.com>
Reviewed-by: NMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

This patch updates the descriptions of 'guest-suspend-ram' and
'guest-suspend-hybrid' to mention that both commands relies now
on the proper support for wake up from suspend, retrieved by the
'wakeup-suspend-support' attribute of the 'query-current-machine'
QMP command.
Reported-by: NBalamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: NMichael Roth <mdroth@linux.vnet.ibm.com>
Message-Id: <20181205194701.17836-3-danielhb413@gmail.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Acked-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

When issuing the qmp/hmp 'system_wakeup' command, what happens in a
nutshell is:

- qmp_system_wakeup_request set runstate to RUNNING, sets a wakeup_reason
and notify the event
- in the main_loop, all vcpus are paused, a system reset is issued, all
subscribers of wakeup_notifiers receives a notification, vcpus are then
resumed and the wake up QAPI event is fired

Note that this procedure alone doesn't ensure that the guest will awake
from SUSPENDED state - the subscribers of the wake up event must take
action to resume the guest, otherwise the guest will simply reboot. At
this moment, only the ACPI machines via acpi_pm1_cnt_init and xen_hvm_init
have wake-up from suspend support.

However, only the presence of 'system_wakeup' is required for QGA to
support 'guest-suspend-ram' and 'guest-suspend-hybrid' at this moment.
This means that the user/management will expect to suspend the guest using
one of those suspend commands and then resume execution using system_wakeup,
regardless of the support offered in system_wakeup in the first place.

This patch creates a new API called query-current-machine [1], that holds
a new flag called 'wakeup-suspend-support' that indicates if the guest
supports wake up from suspend via system_wakeup. The machine is considered
to implement wake-up support if a call to a new 'qemu_register_wakeup_support'
is made during its init, as it is now being done inside acpi_pm1_cnt_init
and xen_hvm_init. This allows for any other machine type to declare wake-up
support regardless of ACPI state or wakeup_notifiers subscription, making easier
for newer implementations that might have their own mechanisms in the future.

This is the expected output of query-current-machine when running a x86
guest:

{"execute" : "query-current-machine"}
{"return": {"wakeup-suspend-support": true}}

Running the same x86 guest, but with the --no-acpi option:

{"execute" : "query-current-machine"}
{"return": {"wakeup-suspend-support": false}}

This is the output when running a pseries guest:

{"execute" : "query-current-machine"}
{"return": {"wakeup-suspend-support": false}}

With this extra tool, management can avoid situations where a guest
that does not have proper suspend/wake capabilities ends up in
inconsistent state (e.g.
https://github.com/open-power-host-os/qemu/issues/31).

[1] the decision of creating the query-current-machine API is based
on discussions in the QEMU mailing list where it was decided that
query-target wasn't a proper place to store the wake-up flag, neither
was query-machines because this isn't a static property of the
machine object. This new API can then be used to store other
dynamic machine properties that are scattered around the code
ATM. More info at:
https://lists.gnu.org/archive/html/qemu-devel/2018-05/msg04235.htmlReported-by: NBalamuruhan S <bala24@linux.vnet.ibm.com>
Signed-off-by: NDaniel Henrique Barboza <danielhb413@gmail.com>
Message-Id: <20181205194701.17836-2-danielhb413@gmail.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Acked-by: NEduardo Habkost <ehabkost@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

It is interesting to know whether the shutdown cause was 'quit' or
'reset', especially when using "--no-reboot". In that case, a management
layer can now determine if the guest wanted a reboot or shutdown, and
can act accordingly.

Changes the output of the reason in the iotests from 'host-qmp' to
'host-qmp-quit'. This does not break compatibility because
the field was introduced in the same version.
Signed-off-by: NDominik Csapak <d.csapak@proxmox.com>
Message-Id: <20181205110131.23049-4-d.csapak@proxmox.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
[Commit message tweaked]
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

This makes it possible to determine what the exact reason was for
a RESET or a SHUTDOWN. A management layer might need the specific reason
of those events to determine which cleanups or other actions it needs to do.

This patch also updates the iotests to the new expected output that includes
the reason.
Signed-off-by: NDominik Csapak <d.csapak@proxmox.com>
Message-Id: <20181205110131.23049-3-d.csapak@proxmox.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
[Commit message tweaked]
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

Needed so the patch after next can add ShutdownCause to QMP events
SHUTDOWN and RESET.
Signed-off-by: NDominik Csapak <d.csapak@proxmox.com>
Message-Id: <20181205110131.23049-2-d.csapak@proxmox.com>
Reviewed-by: NMarkus Armbruster <armbru@redhat.com>
Signed-off-by: NMarkus Armbruster <armbru@redhat.com>

- Remove retranslation remenents
- Return success from patch_reloc
- Preserve 32-bit values as zero-extended on x86_64
- Make bswap during memory ops as optional
- Cleanup xxhash
- Revert constant pooling for tcg/sparc/

# gpg: Signature made Mon 17 Dec 2018 03:25:21 GMT
# gpg:                using RSA key 64DF38E8AF7E215F
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>"
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/pull-tcg-20181216: (33 commits)
  xxhash: match output against the original xxhash32
  include: move exec/tb-hash-xx.h to qemu/xxhash.h
  exec: introduce qemu_xxhash{2,4,5,6,7}
  qht-bench: document -p flag
  tcg: Drop nargs from tcg_op_insert_{before,after}
  tcg/mips: Improve the add2/sub2 command to use TCG_TARGET_REG_BITS
  tcg: Add TCG_TARGET_HAS_MEMORY_BSWAP
  tcg/optimize: Optimize bswap
  tcg: Clean up generic bswap64
  tcg: Clean up generic bswap32
  tcg/i386: Add setup_guest_base_seg for FreeBSD
  tcg/i386: Precompute all guest_base parameters
  tcg/i386: Assume 32-bit values are zero-extended
  tcg/i386: Implement INDEX_op_extr{lh}_i64_i32 for 32-bit guests
  tcg/i386: Propagate is64 to tcg_out_qemu_ld_slow_path
  tcg/i386: Propagate is64 to tcg_out_qemu_ld_direct
  tcg/s390x: Return false on failure from patch_reloc
  tcg/ppc: Return false on failure from patch_reloc
  tcg/arm: Return false on failure from patch_reloc
  tcg/aarch64: Return false on failure from patch_reloc
  ...
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

The pkg.mxe.cc package repositories have been down for the last two
weeks causing the builds to fail when shippable re-builds the
containers.

This is really just a sticking plaster until we can get our own docker
hub images properly setup so we can avoid having dependencies on
external repos.
Signed-off-by: NAlex Bennée <alex.bennee@linaro.org>
Acked-by: NPhilippe Mathieu-Daudé <philmd@redhat.com>
Message-id: 20181214151718.5041-1-alex.bennee@linaro.org
Cc: Philippe Mathieu-Daudé <philmd@redhat.com>
Signed-off-by: NPeter Maydell <peter.maydell@linaro.org>

Change the order in which we extract a/b and c/d to
match the output of the upstream xxhash32.

Tested with:
  https://github.com/cota/xxhash/tree/qemuReviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Tested-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Before moving them all to include/qemu/xxhash.h.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Which we forgot to do in bd224fce ("qht-bench: add -p flag
to precompute hash values", 2018-09-26).
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

It's unused since 75e8b9b7.
Signed-off-by: NEmilio G. Cota <cota@braap.org>
Message-Id: <20181209193749.12277-9-cota@braap.org>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Instead of hard coding 31 for the shift right use TCG_TARGET_REG_BITS - 1.
Signed-off-by: NAlistair Francis <alistair.francis@wdc.com>
Message-Id: <7dfbddf7014a595150aa79011ddb342c3cc17ec3.1544648105.git.alistair.francis@wdc.com>
Reviewed-by: NRichard Henderson <richard.henderson@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

For now, defined universally as true, since we previously required
backends to implement swapped memory operations.  Future patches
may now remove that support where it is onerous.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Somehow we forgot these operations, once upon a time.
This will allow immediate stores to have their bswap
optimized away.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Based on the only current user, Sparc:

New code uses 2 constants that take 2 insns to load from constant pool,
plus 13.  Old code used 6 constants that took 1 or 2 insns to create,
plus 21.  The result is a new total of 17 vs an old total of 29.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Based on the only current user, Sparc:

New code uses 1 constant that takes 2 insns to create, plus 8.
Old code used 2 constants that took 2 insns to create, plus 9.
The result is a new total of 10 vs an old total of 13.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

These values are constant between all qemu_ld/st invocations;
there is no need to figure this out each time.  If we cannot
use a segment or an offset directly for guest_base, load the
value into a register in the prologue.
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

We now have an invariant that all TCG_TYPE_I32 values are
zero-extended, which means that we do not need to extend
them again during qemu_ld/st, either explicitly via a separate
tcg_out_ext32u or implicitly via P_ADDR32.
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

This preserves the invariant that all TCG_TYPE_I32 values are
zero-extended in the 64-bit host register.
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

This helps preserve the invariant that all TCG_TYPE_I32 values
are stored zero-extended in the 64-bit host registers.
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

This helps preserve the invariant that all TCG_TYPE_I32 values
are stored zero-extended in the 64-bit host registers.
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

This does require an extra two checks within the slow paths
to replace the assert that we're moving.  Also add two checks
within existing functions that lacked any kind of assert for
out of range branch.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

The reloc_pc{14,24}_val routines retain their asserts.
Use these directly within the slow paths.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

This does require an extra two checks within the slow paths
to replace the assert that we're moving.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

This does require an extra two checks within the slow paths
to replace the assert that we're moving.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

This will move the assert for success from within (subroutines of)
patch_reloc into the callers.  It will also let new code do something
different when a relocation is out of range.

For the moment, all backends are trivially converted to return true.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

There is no longer a need for preserving branch offset operands,
as we no longer re-translate.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

There is no longer a need for preserving branch offset operands,
as we no longer re-translate.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

There is no longer a need for preserving branch offset operands,
as we no longer re-translate.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

There is no longer a need for preserving branch offset operands,
as we no longer re-translate.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

There are one use apiece for these.  There is no longer a need for
preserving branch offset operands, as we no longer re-translate.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

It is unused since 3fb53fb4.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

There are one use apiece for these.  There is no longer a need for
preserving branch offset operands, as we no longer re-translate.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

It is unused since b68686bd.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>

For x86_64, this can remove a REX prefix resulting in smaller code
when manipulating globals of type i32, as we move them between backing
store via cpu_env, aka TCG_AREG0.
Reviewed-by: NAlex Bennée <alex.bennee@linaro.org>
Reviewed-by: NEmilio G. Cota <cota@braap.org>
Signed-off-by: NRichard Henderson <richard.henderson@linaro.org>