ich9: honour 'enable_tco' property

An 'ICH9-LPC.enable_tco' property has been exposed for a
very long time, but attempts to set it have never been
honoured.

Originally, any user provided 'enable_tco' value was force
replaced by a value passed from the machine type setup
code that was determine by machine type compat properties.

  commit d6b304ba924b95d12edfddaac99777b577301309
  Author: Eduardo Habkost <ehabkost@redhat.com>
  Date:   Sat Jan 23 14:02:10 2016 -0200

    machine: Remove no_tco field

    The field is always set to zero, so it is not necessary anymore.

After legacy Q35 machine types were deleted in:

  commit 86165b499edf8b03bb2d0e926d116c2f12a95bfe
  Author: Eduardo Habkost <ehabkost@redhat.com>
  Date:   Sat Jan 23 14:02:09 2016 -0200

    q35: Remove old machine versions

the machine type code ended up just unconditionally passing
'true', all the time, so this was further simplified in

  commit d6b304ba924b95d12edfddaac99777b577301309
  Author: Eduardo Habkost <ehabkost@redhat.com>
  Date:   Sat Jan 23 14:02:10 2016 -0200

    machine: Remove no_tco field

    The field is always set to zero, so it is not necessary anymore.

  commit 18d6abae3ea092950629e5d26aff1dcfc9a2d78e
  Author: Eduardo Habkost <ehabkost@redhat.com>
  Date:   Sat Jan 23 14:02:11 2016 -0200

    ich9: Remove enable_tco arguments from init functions

    The enable_tco arguments are always true, so they are not needed
    anymore.

Leaving the ich9_pm_init to just force set 'enable_tco' to true.
This still overrides any user specified property. The initialization
of property defaults should be done when properties are first
registered, rather than during object construction.

Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221216125749.596075-6-berrange@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/isa: enable TCO watchdog reboot pin strap by default

The TCO watchdog implementation default behaviour from POV of the
guest OS relies on the initial values for two I/O ports:

  * TCO1_CNT == 0x0

    Since bit 11 (TCO Timer Halt) is clear, the watchdog state
    is considered to be initially running

  * GCS == 0x20

    Since bit 5 (No Reboot) is set, the watchdog will not trigger
    when the timer expires

This is a safe default, because the No Reboot bit will prevent the
watchdog from triggering if the guest OS is unaware of its existance,
or is slow in configuring it. When a Linux guest initializes the TCO
watchdog, it will attempt to clear the "No Reboot" flag, and read the
value back. If the clear was honoured, the driver will treat this as
an indicator that the watchdog is functional and create the guest
watchdog device.

QEMU implements a second "no reboot" flag, however, via pin straps
which overrides the behaviour of the guest controlled "no reboot"
flag:

  commit 5add35bec1e249bb5345a47008c8f298d4760be4
  Author: Paulo Alcantara <pcacjr@gmail.com>
  Date:   Sun Jun 28 14:58:58 2015 -0300

    ich9: implement strap SPKR pin logic

This second 'noreboot' pin was defaulted to high, which also inhibits
triggering of the requested watchdog actions, unless QEMU is launched
with the magic flag "-global ICH9-LPC.noreboot=false".

This is a bad default as we are exposing a watchdog to every guest OS
using the q35 machine type, but preventing it from actually doing what
it is designed to do. What is worse is that the guest OS and its apps
have no way to know that the watchdog is never going to fire, due to
this second 'noreboot' pin.

If a guest OS had no watchdog device at all, then apps whose operation
and/or data integrity relies on a watchdog can refuse to launch, and
alert the administrator of the problematic deployment. With Q35 machines
unconditionally exposing a watchdog though, apps will think their
deployment is correct but in fact have no protection at all.

This patch flips the default of the second 'no reboot' flag, so that
configured watchdog actions will be honoured out of the box for the
7.2 Q35 machine type onwards, if the guest enables use of the watchdog.

See also related bug reports

  https://bugzilla.redhat.com/show_bug.cgi?id=2080207
  https://bugzilla.redhat.com/show_bug.cgi?id=2136889
  https://bugzilla.redhat.com/show_bug.cgi?id=2137346

Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221216125749.596075-5-berrange@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

pc: clean up compat machines

We can move setting default_cpu_version into the base machine options,
and we need to unset alias and is_default only once.

Suggested-by: Thomas Huth <thuth@redhat.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20221212152145.124317-3-cohuck@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Thomas Huth <thuth@redhat.com>

hw: Add compat machines for 8.0

Add 8.0 machine types for arm/i440fx/m68k/q35/s390x/spapr.

Reviewed-by: Cédric Le Goater <clg@kaod.org> [ppc]
Reviewed-by: Thomas Huth <thuth@redhat.com> [s390x]
Reviewed-by: Greg Kurz <groug@kaod.org> [ppc]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20221212152145.124317-2-cohuck@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>

hw/watchdog: add trace events for watchdog action handling

The tracepoints aid in debugging the triggering of watchdog devices.

Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221216125749.596075-4-berrange@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/isa: add trace events for ICH9 LPC chip config access

These tracepoints aid in understanding and debugging the guest drivers
for the TCO watchdog.

Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221216125749.596075-3-berrange@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/acpi: add trace events for TCO watchdog register access

These tracepoints aid in understanding and debugging the guest drivers
for the TCO watchdog.

Reviewed-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Daniel P. Berrangé <berrange@redhat.com>
Message-Id: <20221216125749.596075-2-berrange@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

Merge tag 'pull-misc-20221218' of https://gitlab.com/rth7680/qemu into staging

Fix tricore gdbstub.
Fix superh_cpu_synchronize_from_tb.

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* tag 'pull-misc-20221218' of https://gitlab.com/rth7680/qemu:
  target/tricore: Fix gdbstub write to address registers
  target/sh4: Mask restore of env->flags from tb->flags

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/tricore: Fix gdbstub write to address registers

Typo had double-writes to data registers.

Resolves: https://gitlab.com/qemu-project/qemu/-/issues/1363
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

target/sh4: Mask restore of env->flags from tb->flags

The values in env->flags are a subset of tb->flags.
Restore only the bits that belong.

Cc: qemu-stable@nongnu.org
Fixes: ab419fd8a035 ("target/sh4: Fix TB_FLAG_UNALIGN")
Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Message-ID: <20221212011345.GA2235238@roeck-us.net>
[rth: Reduce to only the the superh_cpu_synchronize_from_tb change]
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

Merge tag 'pull-hex-20221216-1' of https://github.com/quic/qemu into staging

1)
Performance improvement
Add pkt and insn to DisasContext
Many functions need information from all 3 structures, so merge
them together.

2)
Bug fix
Fix predicated assignment to .tmp and .cur

3)
Performance improvement
Add overrides for S2_asr_r_r_sat/S2_asl_r_r_sat
These functions will not be handled by idef-parser

4-11)
The final 8 patches improve change-of-flow handling.

Currently, we set the PC to a new address before exiting a TB.  The
ultimate goal is to use direct block chaining.  However, several steps
are needed along the way.

4)
When a packet has more than one change-of-flow (COF) instruction, only
the first one taken is considered.  The runtime bookkeeping is only
needed when there is more than one COF instruction in a packet.

5, 6)
Remove PC and next_PC from the runtime state and always use a
translation-time constant.  Note that next_PC is used by call instructions
to set LR and by conditional COF instructions to set the fall-through
address.

7, 8, 9)
Add helper overrides for COF instructions.  In particular, we must
distinguish those that use a PC-relative address for the destination.
These are candidates for direct block chaining later.

10)
Use direct block chaining for packets that have a single PC-relative
COF instruction.  Instead of generating the code while processing the
instruction, we record the effect in DisasContext and generate the code
during gen_end_tb.

11)
Use direct block chaining for tight loops.  We look for TBs that end
with an endloop0 that will branch back to the TB start address.

12-21)
Instruction definition parser (idef-parser) from rev.ng
Parses the instruction semantics and generates TCG

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* tag 'pull-hex-20221216-1' of https://github.com/quic/qemu: (21 commits)
  target/hexagon: import additional tests
  target/hexagon: call idef-parser functions
  target/hexagon: import parser for idef-parser
  target/hexagon: import lexer for idef-parser
  target/hexagon: prepare input for the idef-parser
  target/hexagon: introduce new helper functions
  target/hexagon: make helper functions non-static
  target/hexagon: make slot number an unsigned
  target/hexagon: import README for idef-parser
  target/hexagon: update MAINTAINERS for idef-parser
  Hexagon (target/hexagon) Use direct block chaining for tight loops
  Hexagon (target/hexagon) Use direct block chaining for direct jump/branch
  Hexagon (target/hexagon) Add overrides for various forms of jump
  Hexagon (target/hexagon) Add overrides for compound compare and jump
  Hexagon (target/hexagon) Add overrides for direct call instructions
  Hexagon (target/hexagon) Remove next_PC from runtime state
  Hexagon (target/hexagon) Remove PC from the runtime state
  Hexagon (target/hexagon) Only use branch_taken when packet has multi cof
  Hexagon (target/hexagon) Add overrides for S2_asr_r_r_sat/S2_asl_r_r_sat
  Hexagon (target/hexagon) Fix predicated assignment to .tmp and .cur
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Merge tag 'pull-loongarch-20221215' of https://gitlab.com/gaosong/qemu into staging

Add cfi01 pflash device

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* tag 'pull-loongarch-20221215' of https://gitlab.com/gaosong/qemu:
  hw/loongarch/virt: Add cfi01 pflash device

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Merge tag 'pull-target-arm-20221216' of https://git.linaro.org/people/pmaydell/qemu-arm into staging

reset refactoring queue:
 * remove uses of qdev_reset_all(), qbus_reset_all(), device_legacy_reset()
 * convert various devices to 3-phase reset, so we can remove their
   uses of device_class_set_parent_reset()

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* tag 'pull-target-arm-20221216' of https://git.linaro.org/people/pmaydell/qemu-arm: (36 commits)
  hw/pci-host/pnv_phb3_msi: Convert TYPE_PHB3_MSI to 3-phase reset
  hw/intc/xics: Convert TYPE_ICS to 3-phase reset
  hw/intc/xics: Reset TYPE_ICS objects with device_cold_reset()
  pci: Convert child classes of TYPE_PCIE_ROOT_PORT to 3-phase reset
  pci: Convert TYPE_PCIE_ROOT_PORT to 3-phase reset
  hw/display/virtio-vga: Convert TYPE_VIRTIO_VGA_BASE to 3-phase reset
  hw/virtio: Convert TYPE_VIRTIO_PCI to 3-phase reset
  target/xtensa: Convert to 3-phase reset
  target/tricore: Convert to 3-phase reset
  target/sparc: Convert to 3-phase reset
  target/sh4: Convert to 3-phase reset
  target/rx: Convert to 3-phase reset
  target/riscv: Convert to 3-phase reset
  target/ppc: Convert to 3-phase reset
  target/openrisc: Convert to 3-phase reset
  target/nios2: Convert to 3-phase reset
  target/mips: Convert to 3-phase reset
  target/microblaze: Convert to 3-phase reset
  target/m68k: Convert to 3-phase reset
  target/loongarch: Convert to 3-phase reset
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/hexagon: import additional tests

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Niccolò Izzo <nizzo@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-12-anjo@rev.ng>

target/hexagon: call idef-parser functions

Extend gen_tcg_funcs.py in order to emit calls to the functions emitted
by the idef-parser, if available.

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-11-anjo@rev.ng>

target/hexagon: import parser for idef-parser

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Paolo Montesel <babush@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-10-anjo@rev.ng>

target/hexagon: import lexer for idef-parser

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Paolo Montesel <babush@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-9-anjo@rev.ng>

target/hexagon: prepare input for the idef-parser

Introduce infrastructure necessary to produce a file suitable for being
parsed by the idef-parser. A build option is also added to fully disable
the output of idef-parser, which is useful for debugging.

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-8-anjo@rev.ng>

target/hexagon: introduce new helper functions

These helpers will be employed by the idef-parser generated code, to
correctly implement instruction semantics. "Helper" functions, in the
context of this patch, refers to functions which provide a manual TCG
implementation of certain features.

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Niccolò Izzo <nizzo@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-6-anjo@rev.ng>

target/hexagon: make helper functions non-static

Make certain helper functions non-static, making them available outside
genptr.c. These functions are required by code generated by the
idef-parser.

This commit also makes some functions in op_helper.c non-static in order
to avoid having them marked as unused when using the idef-parser
generated code.

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Paolo Montesel <babush@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-5-anjo@rev.ng>

target/hexagon: make slot number an unsigned

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Paolo Montesel <babush@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Acked-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-4-anjo@rev.ng>

target/hexagon: import README for idef-parser

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-3-anjo@rev.ng>

target/hexagon: update MAINTAINERS for idef-parser

Signed-off-by: Alessandro Di Federico <ale@rev.ng>
Signed-off-by: Anton Johansson <anjo@rev.ng>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20220923173831.227551-2-anjo@rev.ng>

Hexagon (target/hexagon) Use direct block chaining for tight loops

Direct block chaining is documented here
https://qemu.readthedocs.io/en/latest/devel/tcg.html#direct-block-chaining

Hexagon inner loops end with the endloop0 instruction
To go back to the beginning of the loop, this instructions writes to PC
from register SA0 (start address 0).  To use direct block chaining, we
have to assign PC with a constant value.  So, we specialize the code
generation when the start of the translation block is equal to SA0.

When this is the case, we defer the compare/branch from endloop0 to
gen_end_tb.  When this is done, we can assign the start address of the TB
to PC.

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-12-tsimpson@quicinc.com>

Hexagon (target/hexagon) Use direct block chaining for direct jump/branch

Direct block chaining is documented here
https://qemu.readthedocs.io/en/latest/devel/tcg.html#direct-block-chaining

Recall that Hexagon allows packets with multiple jumps where only the
first one with a true predicate will actually jump.  We can  use
tcg_gen_goto_tb/tcg_gen_exit_tb when the packet contains a single
PC-relative branch or jump.  If not, we use tcg_gen_lookup_and_goto_ptr.

We add the following to DisasContext in order to delay the branching
until the end of packet commit (in gen_end_tb)
    branch_cond
        The TCGCond condition under which the branch is taken
        When branch_cond == TCG_COND_NEVER, there isn't a single
        direct branch in this packet.
        When branch_cond != TCG_COND_ALWAYS, the value is in
        hex_branch_taken
    branch_dest
        The destination of the branch

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-11-tsimpson@quicinc.com>

Hexagon (target/hexagon) Add overrides for various forms of jump

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-10-tsimpson@quicinc.com>

Hexagon (target/hexagon) Add overrides for compound compare and jump

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-9-tsimpson@quicinc.com>

Hexagon (target/hexagon) Add overrides for direct call instructions

Add overrides for
    J2_call
    J2_callt
    J2_callf

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-8-tsimpson@quicinc.com>

Hexagon (target/hexagon) Remove next_PC from runtime state

The imported files don't properly mark all CONDEXEC instructions, so
we add some logic to hex_common.py to add the attribute.

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-7-tsimpson@quicinc.com>

Hexagon (target/hexagon) Remove PC from the runtime state

Add pc field to Packet structure
For helpers that need PC, pass an extra argument
Remove slot arg from conditional jump helpers
On a trap0, copy pkt->pc into hex_gpr[HEX_REG_PC]

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-6-tsimpson@quicinc.com>

Hexagon (target/hexagon) Only use branch_taken when packet has multi cof

When a packet has more than one change-of-flow instruction, only the first
one to branch is considered.  We use the branch_taken variable to keep
track of this.

However, when there is a single cof instruction, we don't need the same
amount of bookkeeping.

We add the pkt_has_multi_cof member to the Packet structure, and pass this
information to the needed functions.

When there is a generated helper function with cof, the generator will
pass this pkt_has_multi_cof as a runtime value.

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-5-tsimpson@quicinc.com>

Hexagon (target/hexagon) Add overrides for S2_asr_r_r_sat/S2_asl_r_r_sat

These instructions will not be generated by idef-parser, so we override
them manually.

Test cases added to tests/tcg/hexagon/usr.c

Co-authored-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20221108162906.3166-4-tsimpson@quicinc.com>

Hexagon (target/hexagon) Fix predicated assignment to .tmp and .cur

Here are example instructions with a predicated .tmp/.cur assignment
    if (p1) v12.tmp = vmem(r7 + #0)
    if (p0) v12.cur = vmem(r9 + #0)
The .tmp/.cur indicates that references to v12 in the same packet
take the result of the load.  However, when the predicate is false,
the value at the start of the packet should be used.  After the packet
commits, the .tmp value is dropped, but the .cur value is maintained.

To fix this bug, we preload the original value from the HVX register
into the temporary used for the result.

Test cases added to tests/tcg/hexagon/hvx_misc.c

Acked-by: Richard Henderson <richard.henderson@linaro.org>
Co-authored-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Matheus Tavares Bernardino <quic_mathbern@quicinc.com>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-3-tsimpson@quicinc.com>

Hexagon (target/hexagon) Add pkt and insn to DisasContext

This enables us to reduce the number of parameters to many functions
In particular, the generated functions previously took all 3 as arguments

Not only does this simplify the code, it improves the translation time

Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Signed-off-by: Taylor Simpson <tsimpson@quicinc.com>
Message-Id: <20221108162906.3166-2-tsimpson@quicinc.com>

hw/pci-host/pnv_phb3_msi: Convert TYPE_PHB3_MSI to 3-phase reset

Convert the TYPE_PHB3_MSI class to 3-phase reset, so we can
avoid using the device_class_set_parent_reset() function.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221125115240.3005559-8-peter.maydell@linaro.org

hw/intc/xics: Convert TYPE_ICS to 3-phase reset

Convert the TYPE_ICS class to 3-phase reset; this will allow us
to convert the TYPE_PHB3_MSI class which inherits from it.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221125115240.3005559-7-peter.maydell@linaro.org

hw/intc/xics: Reset TYPE_ICS objects with device_cold_reset()

The realize method for the TYPE_ICS class uses qemu_register_reset()
to register a reset handler, as a workaround for the fact that
currently objects which directly inherit from TYPE_DEVICE don't get
automatically reset.  However, the reset function directly calls
ics_reset(), which is the function that implements the legacy reset
method.  This means that only the parent class's data gets reset, and
a subclass which also needs to handle reset, like TYPE_PHB3_MSI, has
to register its own reset function.

Make the TYPE_ICS reset function call device_cold_reset() instead:
this will handle reset for both the parent class and the subclass,
and will work whether the classes are using legacy reset or 3-phase
reset. This allows us to remove the reset function that the subclass
currently has to set up.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221125115240.3005559-6-peter.maydell@linaro.org

pci: Convert child classes of TYPE_PCIE_ROOT_PORT to 3-phase reset

Convert the TYPE_CXL_ROOT_PORT and TYPE_PNV_PHB_ROOT_PORT classes to
3-phase reset, so they don't need to use the deprecated
device_class_set_parent_reset() function any more.

We have to do both in the same commit, because they keep the
parent_reset field in their common parent class's class struct.

Note that pnv_phb_root_port_class_init() was pointlessly setting
dc->reset twice, once by calling device_class_set_parent_reset()
and once directly.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221125115240.3005559-5-peter.maydell@linaro.org

pci: Convert TYPE_PCIE_ROOT_PORT to 3-phase reset

Convert the TYPE_PCIE_ROOT_PORT device to 3-phase reset; this is a
necessary precursor to converting any of its child classes.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221125115240.3005559-4-peter.maydell@linaro.org

hw/display/virtio-vga: Convert TYPE_VIRTIO_VGA_BASE to 3-phase reset

Convert the TYPE_VIRTIO_VGA_BASE class to 3-phase reset, so we
don't need to use device_class_set_parent_reset() any more.

Note that this is an abstract class itself; none of the subclasses
override its reset method.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221125115240.3005559-3-peter.maydell@linaro.org

hw/virtio: Convert TYPE_VIRTIO_PCI to 3-phase reset

Convert the TYPE_VIRTIO_PCI class to 3-phase reset.  This is
necessary so that we can convert the subclass TYPE_VIRTIO_VGA_BASE
also to 3-phase reset.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Tested-by: Daniel Henrique Barboza <danielhb413@gmail.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221125115240.3005559-2-peter.maydell@linaro.org

target/xtensa: Convert to 3-phase reset

Convert the xtensa CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-id: 20221124115023.2437291-20-peter.maydell@linaro.org

target/tricore: Convert to 3-phase reset

Convert the tricore CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-id: 20221124115023.2437291-19-peter.maydell@linaro.org

target/sparc: Convert to 3-phase reset

Convert the sparc CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Reviewed-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Message-id: 20221124115023.2437291-18-peter.maydell@linaro.org

target/sh4: Convert to 3-phase reset

Convert the sh4 CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-id: 20221124115023.2437291-17-peter.maydell@linaro.org

target/rx: Convert to 3-phase reset

Convert the rx CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-id: 20221124115023.2437291-16-peter.maydell@linaro.org

target/riscv: Convert to 3-phase reset

Convert the riscv CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-id: 20221124115023.2437291-15-peter.maydell@linaro.org

target/ppc: Convert to 3-phase reset

Convert the ppc CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Reviewed-by: Greg Kurz <groug@kaod.org>
Message-id: 20221124115023.2437291-14-peter.maydell@linaro.org

target/openrisc: Convert to 3-phase reset

Convert the openrisc CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-id: 20221124115023.2437291-13-peter.maydell@linaro.org

target/nios2: Convert to 3-phase reset

Convert the nios2 CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-id: 20221124115023.2437291-12-peter.maydell@linaro.org

target/mips: Convert to 3-phase reset

Convert the mips CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-id: 20221124115023.2437291-11-peter.maydell@linaro.org

target/microblaze: Convert to 3-phase reset

Convert the microblaze CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-id: 20221124115023.2437291-10-peter.maydell@linaro.org

target/m68k: Convert to 3-phase reset

Convert the m68k CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-id: 20221124115023.2437291-9-peter.maydell@linaro.org

target/loongarch: Convert to 3-phase reset

Convert the loongarch CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-id: 20221124115023.2437291-8-peter.maydell@linaro.org

target/i386: Convert to 3-phase reset

Convert the i386 CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-id: 20221124115023.2437291-7-peter.maydell@linaro.org

target/hexagon: Convert to 3-phase reset

Convert the hexagon CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Reviewed-by: Taylor Simpson <tsimpson@quicinc.com>
Message-id: 20221124115023.2437291-6-peter.maydell@linaro.org

target/cris: Convert to 3-phase reset

Convert the cris CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Edgar E. Iglesias <edgar@zeroasic.com>
Message-id: 20221124115023.2437291-5-peter.maydell@linaro.org

target/avr: Convert to 3-phase reset

Convert the avr CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20221124115023.2437291-4-peter.maydell@linaro.org

target/arm: Convert to 3-phase reset

Convert the Arm CPU class to use 3-phase reset, so it doesn't
need to use device_class_set_parent_reset() any more.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Message-id: 20221124115023.2437291-3-peter.maydell@linaro.org

hw/core/cpu-common: Convert TYPE_CPU class to 3-phase reset

Convert the parent class TYPE_CPU to 3-phase reset. This
is a necessary prerequisite to converting the subclasses.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Alistair Francis <alistair.francis@wdc.com>
Message-id: 20221124115023.2437291-2-peter.maydell@linaro.org

hw/misc: Convert TYPE_MOS6522 subclasses to 3-phase reset

Convert the various subclasses of TYPE_MOS6522 to 3-phase reset.
This removes some uses of device_class_set_parent_reset(), which we
would eventually like to be able to get rid of.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221110143459.3833425-3-peter.maydell@linaro.org

hw/misc/mos6522: Convert TYPE_MOS6522 to 3-phase reset

Convert the TYPE_MOS6522 parent class to use 3-phase reset.  This is
a prerequisite for converting its subclasses.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Acked-by: Mark Cave-Ayland <mark.cave-ayland@ilande.co.uk>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20221110143459.3833425-2-peter.maydell@linaro.org

hw/input/ps2.c: Convert TYPE_PS2_{KBD, MOUSE}_DEVICE to 3-phase reset

Convert the child classes TYPE_PS2_KBD_DEVICE and
TYPE_PS2_MOUSE_DEVICE to the 3-phase reset system.  This allows us to
stop using the old device_class_set_parent_reset() function.

We don't need to register an 'exit' phase function for the
subclasses, because they have no work to do in that phase.  Passing
NULL to resettable_class_set_parent_phases() will result in the
parent class method being called for that phase, so we don't need to
register a function purely to chain to the parent 'exit' phase
function.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221109170009.3498451-3-peter.maydell@linaro.org

hw/input/ps2: Convert TYPE_PS2_DEVICE to 3-phase reset

Convert the parent class TYPE_PS2_DEVICE to 3-phase reset.  Note that
we need an 'exit' phase function as well as the usual 'hold' phase
function, because changing outbound IRQ line state is only permitted
in 'exit'.  (Strictly speaking it's not supposed to be done in a
legacy reset handler either, but you can often get away with it.)

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20221109170009.3498451-2-peter.maydell@linaro.org

hw: Remove device_legacy_reset()

The device_legacy_reset() function is now not used anywhere, so we
can remove the implementation.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

qdev: Remove qdev_reset_all() and qbus_reset_all()

Remove the qdev_reset_all() and qbus_reset_all() functions, now we
have moved all the callers over to the new device_cold_reset() and
bus_cold_reset() functions.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Replace use of qdev_reset_all() with device_cold_reset()

The legacy function qdev_reset_all() performs a recursive reset,
starting from a qdev.  However, it does not permit any of the devices
in the tree to use three-phase reset, because device reset goes
through the device_legacy_reset() function that only calls the single
DeviceClass::reset method.

Switch to using the device_cold_reset() function instead.  This also
performs a recursive reset, where first the children are reset and
then finally the parent, but it uses the new (...in 2020...)
Resettable mechanism, which supports both the old style single-reset
method and also the new 3-phase reset handling.

This commit changes the five remaining uses of this function.

Commit created with:
 sed -i -e 's/qdev_reset_all/device_cold_reset/g' hw/i386/xen/xen_platform.c hw/input/adb.c hw/remote/vfio-user-obj.c hw/s390x/s390-virtio-ccw.c hw/usb/dev-uas.c

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/hyperv/vmbus: Use device_cold_reset() and bus_cold_reset()

In the vmbus code we currently use the legacy functions
qdev_reset_all() and qbus_reset_all().  These perform a recursive
reset, starting from either a qbus or a qdev.  However they do not
permit any of the devices in the tree to use three-phase reset,
because device reset goes through the device_legacy_reset() function
that only calls the single DeviceClass::reset method.

Switch to using the device_cold_reset() and bus_cold_reset()
functions.  These also perform a recursive reset, where first the
children are reset and then finally the parent, but they use the new
(...in 2020...) Resettable mechanism, which supports both the old
style single-reset method and also the new 3-phase reset handling.

This should be a no-behaviour-change commit which just reduces the
use of a deprecated API.

Commit created with:
  sed -i -e 's/qdev_reset_all/device_cold_reset/g;s/qbus_reset_all/bus_cold_reset/g' hw/hyperv/*.c

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

pci: Use device_cold_reset() and bus_cold_reset()

In the PCI subsystem we currently use the legacy function
qdev_reset_all() and qbus_reset_all().  These perform a recursive
reset, starting from either a qbus or a qdev.  However they do not
permit any of the devices in the tree to use three-phase reset,
because device reset goes through the device_legacy_reset() function
that only calls the single DeviceClass::reset method.

Switch to using the device_cold_reset() and bus_cold_reset()
functions.  These also perform a recursive reset, where first the
children are reset and then finally the parent, but they use the new
(...in 2020...) Resettable mechanism, which supports both the old
style single-reset method and also the new 3-phase reset handling.

This should be a no-behaviour-change commit which just reduces the
use of a deprecated API.

Commit created with:
 sed -i -e 's/qdev_reset_all/device_cold_reset/g;s/qbus_reset_all/bus_cold_reset/g' hw/pci/*.c

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/s390x/s390-pci-inst.c: Use device_cold_reset() to reset PCI devices

The semantic difference between the deprecated device_legacy_reset()
function and the newer device_cold_reset() function is that the new
function resets both the device itself and any qbuses it owns,
whereas the legacy function resets just the device itself and nothing
else.

In s390-pci-inst.c we use device_legacy_reset() to reset an
S390PCIBusDevice.  This device doesn't have any child qbuses, so the
functions do the same thing and we can stop using the deprecated one.

Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Merge tag 'for-upstream' of https://repo.or.cz/qemu/kevin into staging

Block layer patches

- Code cleanups around block graph modification
- Simplify drain
- coroutine_fn correctness fixes, including splitting generated
  coroutine wrappers into co_wrapper (to be called only from
  non-coroutine context) and co_wrapper_mixed (both coroutine and
  non-coroutine context)
- Introduce a block graph rwlock

# gpg: Signature made Thu 15 Dec 2022 15:08:34 GMT
# gpg:                using RSA key DC3DEB159A9AF95D3D7456FE7F09B272C88F2FD6
# gpg:                issuer "kwolf@redhat.com"
# gpg: Good signature from "Kevin Wolf <kwolf@redhat.com>" [full]
# Primary key fingerprint: DC3D EB15 9A9A F95D 3D74  56FE 7F09 B272 C88F 2FD6

* tag 'for-upstream' of https://repo.or.cz/qemu/kevin: (50 commits)
  block: GRAPH_RDLOCK for functions only called by co_wrappers
  block: use co_wrapper_mixed_bdrv_rdlock in functions taking the rdlock
  block-coroutine-wrapper.py: introduce annotations that take the graph rdlock
  Mark assert_bdrv_graph_readable/writable() GRAPH_RD/WRLOCK
  graph-lock: TSA annotations for lock/unlock functions
  block: assert that graph read and writes are performed correctly
  block: remove unnecessary assert_bdrv_graph_writable()
  block: wrlock in bdrv_replace_child_noperm
  block: Fix locking in external_snapshot_prepare()
  test-bdrv-drain: Fix incorrrect drain assumptions
  clang-tsa: Add macros for shared locks
  clang-tsa: Add TSA_ASSERT() macro
  Import clang-tsa.h
  async: Register/unregister aiocontext in graph lock list
  graph-lock: Implement guard macros
  graph-lock: Introduce a lock to protect block graph operations
  block: Factor out bdrv_drain_all_begin_nopoll()
  block/dirty-bitmap: convert coroutine-only functions to co_wrapper
  block: convert bdrv_create to co_wrapper
  block-coroutine-wrapper.py: support also basic return types
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Merge tag 'pull-request-2022-12-15' of https://gitlab.com/thuth/qemu into staging

* s390x PCI fixes and improvements (for the ISM device)
* Fix emulated MVCP and MVCS s390x instructions
* Clean-ups for the e1000e qtest
* Enable qtests on Windows
* Update FreeBSD CI to version 12.4
* Check --disable-tcg for ppc64 in the CI
* Improve scripts/make-releases a little bit
* Many other misc small clean-ups and fixes here and there

# gpg: Signature made Thu 15 Dec 2022 15:05:44 GMT
# gpg:                using RSA key 27B88847EEE0250118F3EAB92ED9D774FE702DB5
# gpg:                issuer "thuth@redhat.com"
# gpg: Good signature from "Thomas Huth <th.huth@gmx.de>" [full]
# gpg:                 aka "Thomas Huth <thuth@redhat.com>" [full]
# gpg:                 aka "Thomas Huth <huth@tuxfamily.org>" [full]
# gpg:                 aka "Thomas Huth <th.huth@posteo.de>" [unknown]
# Primary key fingerprint: 27B8 8847 EEE0 2501 18F3  EAB9 2ED9 D774 FE70 2DB5

* tag 'pull-request-2022-12-15' of https://gitlab.com/thuth/qemu: (23 commits)
  tests/qtest/vhost-user-blk-test: don't abort all qtests on missing envar
  .gitlab/issue_templates: Move suggestions into comments
  gitlab-ci: Check building ppc64 without TCG
  FreeBSD: Upgrade to 12.4 release
  tests/qtest: Enable qtest build on Windows
  .gitlab-ci.d/windows.yml: Exclude qTests from 64-bit CI job for now
  .gitlab-ci.d/windows.yml: Keep 64-bit and 32-bit build scripts consistent
  .gitlab-ci.d/windows.yml: Unify the prerequisite packages
  tests/qtest/libqos/e1000e: Correctly group register accesses
  tests/qtest/e1000e-test: De-duplicate constants
  tests/qtest/libqos/e1000e: Remove "other" interrupts
  hw: Include the VMWare devices only in the x86 targets
  MAINTAINERS: Add documentation files to the corresponding sections
  util/oslib-win32: Remove obsolete reference to g_poll code
  util/qemu-config: Fix "query-command-line-options" to provide the right values
  scripts/make-release: Only clone single branches to speed up the script
  scripts/make-release: Add a simple help text for the script
  monitor/misc: Remove superfluous include statements
  target/s390x: The MVCP and MVCS instructions are not privileged
  target/s390x/tcg/mem_helper: Test the right bits in psw_key_valid()
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

Merge tag 'pull-target-arm-20221215-1' of https://git.linaro.org/people/pmaydell/qemu-arm into staging

target-arm queue:
 * hw/arm/virt: Add properties to allow more granular
   configuration of use of highmem space
 * target/arm: Add Cortex-A55 CPU
 * hw/intc/arm_gicv3: Fix GICD_TYPER ITLinesNumber advertisement
 * Implement FEAT_EVT
 * Some 3-phase-reset conversions for Arm GIC, SMMU
 * hw/arm/boot: set initrd with #address-cells type in fdt
 * hw/misc: Move some arm-related files from specific_ss into softmmu_ss
 * Restrict arm_cpu_exec_interrupt() to TCG accelerator

# gpg: Signature made Thu 15 Dec 2022 17:38:36 GMT
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# gpg:                issuer "peter.maydell@linaro.org"
# gpg: Good signature from "Peter Maydell <peter.maydell@linaro.org>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@gmail.com>" [ultimate]
# gpg:                 aka "Peter Maydell <pmaydell@chiark.greenend.org.uk>" [ultimate]
# gpg:                 aka "Peter Maydell <peter@archaic.org.uk>" [ultimate]
# Primary key fingerprint: E1A5 C593 CD41 9DE2 8E83  15CF 3C25 25ED 1436 0CDE

* tag 'pull-target-arm-20221215-1' of https://git.linaro.org/people/pmaydell/qemu-arm: (28 commits)
  target/arm: Restrict arm_cpu_exec_interrupt() to TCG accelerator
  hw/misc: Move some arm-related files from specific_ss into softmmu_ss
  hw/arm/boot: set initrd with #address-cells type in fdt
  hw/intc: Convert TYPE_KVM_ARM_ITS to 3-phase reset
  hw/intc: Convert TYPE_ARM_GICV3_ITS to 3-phase reset
  hw/intc: Convert TYPE_ARM_GICV3_ITS_COMMON to 3-phase reset
  hw/intc: Convert TYPE_KVM_ARM_GICV3 to 3-phase reset
  hw/intc: Convert TYPE_ARM_GICV3_COMMON to 3-phase reset
  hw/intc: Convert TYPE_ARM_GIC_KVM to 3-phase reset
  hw/intc: Convert TYPE_ARM_GIC_COMMON to 3-phase reset
  hw/arm: Convert TYPE_ARM_SMMUV3 to 3-phase reset
  hw/arm: Convert TYPE_ARM_SMMU to 3-phase reset
  target/arm: Report FEAT_EVT for TCG '-cpu max'
  target/arm: Implement HCR_EL2.TID4 traps
  target/arm: Implement HCR_EL2.TICAB,TOCU traps
  target/arm: Implement HCR_EL2.TTLBOS traps
  target/arm: Implement HCR_EL2.TTLBIS traps
  target/arm: Allow relevant HCR bits to be written for FEAT_EVT
  hw/intc/arm_gicv3: Fix GICD_TYPER ITLinesNumber advertisement
  target/arm: Add Cortex-A55 CPU
  ...

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

target/arm: Restrict arm_cpu_exec_interrupt() to TCG accelerator

When building with --disable-tcg on Darwin we get:

  target/arm/cpu.c:725:16: error: incomplete definition of type 'struct TCGCPUOps'
    cc->tcg_ops->do_interrupt(cs);
    ~~~~~~~~~~~^

Commit 083afd18a9 ("target/arm: Restrict cpu_exec_interrupt()
handler to sysemu") limited this block to system emulation,
but neglected to also limit it to TCG.

Signed-off-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Fabiano Rosas <farosas@suse.de>
Message-id: 20221209110823.59495-1-philmd@linaro.org
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

hw/misc: Move some arm-related files from specific_ss into softmmu_ss

The header target/arm/kvm-consts.h checks CONFIG_KVM which is marked as
poisoned in common code, so the files that include this header have to
be added to specific_ss and recompiled for each, qemu-system-arm and
qemu-system-aarch64. However, since the kvm headers are only optionally
used in kvm-constants.h for some sanity checks, we can additionally
check the NEED_CPU_H macro first to avoid the poisoned CONFIG_KVM macro,
so kvm-constants.h can also be used from "common" files (without the
sanity checks - which should be OK since they are still done from other
target-specific files instead). This way, and by adjusting some other
include statements in the related files here and there, we can move some
files from specific_ss into softmmu_ss, so that they only need to be
compiled once during the build process.

Signed-off-by: Thomas Huth <thuth@redhat.com>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Message-id: 20221202154023.293614-1-thuth@redhat.com
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

block: GRAPH_RDLOCK for functions only called by co_wrappers

The generated coroutine wrappers already take care to take the lock in
the non-coroutine path, and assume that the lock is already taken in the
coroutine path.

The only thing we need to do for the wrapped function is adding the
GRAPH_RDLOCK annotation. Doing so also allows us to mark the
corresponding callbacks in BlockDriver as GRAPH_RDLOCK_PTR.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-19-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: use co_wrapper_mixed_bdrv_rdlock in functions taking the rdlock

Take the rdlock already, before we add the assertions.

All these functions either read the graph recursively, or call
BlockDriver callbacks that will eventually need to be protected by the
graph rdlock.

Do it now to all functions together, because many of these recursively
call each other.

For example, bdrv_co_truncate calls BlockDriver->bdrv_co_truncate, and
some driver callbacks implement their own .bdrv_co_truncate by calling
bdrv_flush inside. So if bdrv_flush asserts but bdrv_truncate does not
take the rdlock yet, the assertion will always fail.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-18-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block-coroutine-wrapper.py: introduce annotations that take the graph rdlock

Add co_wrapper_bdrv_rdlock and co_wrapper_mixed_bdrv_rdlock option to
the block-coroutine-wrapper.py script.

This "_bdrv_rdlock" option takes and releases the graph rdlock when a
coroutine function is created.

This means that when used together with "_mixed", the function marked
with co_wrapper_mixed_bdrv_rdlock will support both coroutine and
non-coroutine case, and in the latter case it will create a coroutine
that takes and releases the rdlock. When called from a coroutine, the
caller must already hold the graph lock.

Example:
void co_wrapper_mixed_bdrv_rdlock bdrv_f1();

Becomes

static void bdrv_co_enter_f1()
{
    bdrv_graph_co_rdlock();
    bdrv_co_function();
    bdrv_graph_co_rdunlock();
}

void bdrv_f1()
{
    if (qemu_in_coroutine) {
        assume_graph_lock();
        bdrv_co_function();
    } else {
        qemu_co_enter(bdrv_co_enter_f1);
        ...
    }
}

When used alone, the function will not work in coroutine context, and
when called in non-coroutine context it will create a new coroutine that
takes care of taking and releasing the rdlock automatically.

Example:
void co_wrapper_bdrv_rdlock bdrv_f1();

Becomes

static void bdrv_co_enter_f1()
{
    bdrv_graph_co_rdlock();
    bdrv_co_function();
    bdrv_graph_co_rdunlock();
}

void bdrv_f1()
{
    assert(!qemu_in_coroutine());
    qemu_co_enter(bdrv_co_enter_f1);
    ...
}

About their usage:
- co_wrapper does not take the rdlock, so it can be used also outside
  the block layer.
- co_wrapper_mixed will be used by many blk_* functions, since the
  coroutine function needs to call blk_wait_while_drained() and
  the rdlock *must* be taken afterwards, otherwise it's a deadlock.
  In the future this annotation will go away, and blk_* will use
  co_wrapper directly.
- co_wrapper_bdrv_rdlock will be used by BlockDriver callbacks, ideally
  by all of them in the future.
- co_wrapper_mixed_bdrv_rdlock will be used by the remaining functions
  that are still called by coroutine and non-coroutine context. In the
  future this annotation will go away, as we will split such mixed
  functions.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-17-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Mark assert_bdrv_graph_readable/writable() GRAPH_RD/WRLOCK

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-16-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

graph-lock: TSA annotations for lock/unlock functions

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-15-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: assert that graph read and writes are performed correctly

Remove the old assert_bdrv_graph_writable, and replace it with
the new version using graph-lock API.

See the function documentation for more information.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-14-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: remove unnecessary assert_bdrv_graph_writable()

We don't protect bdrv->aio_context with the graph rwlock,
so these assertions are not needed

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-13-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: wrlock in bdrv_replace_child_noperm

Protect the main function where graph is modified.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-12-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: Fix locking in external_snapshot_prepare()

bdrv_img_create() polls internally (when calling bdrv_create(), which is
a co_wrapper), so it can't be called while holding the lock of any
AioContext except the current one without causing deadlocks. Drop the
lock around the call in external_snapshot_prepare().

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-11-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

test-bdrv-drain: Fix incorrrect drain assumptions

The test case assumes that a drain only happens in one specific place
where it drains explicitly. This assumption happened to hold true until
now, but block layer functions may drain interally (any graph
modifications are going to do that through bdrv_graph_wrlock()), so this
is incorrect. Make sure that the test code in .drained_begin only runs
where we actually want it to run.

When scheduling a BH from .drained_begin, we also need to increase the
in_flight counter to make sure that the operation is actually completed
in time before the node that it works on goes away.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-10-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

clang-tsa: Add macros for shared locks

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-8-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

clang-tsa: Add TSA_ASSERT() macro

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-7-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

Import clang-tsa.h

This defines macros that allow clang to perform Thread Safety Analysis
based on function and variable annotations that specify the locking
rules. On non-clang compilers, the annotations are ignored.

Imported tsa.h from the original repository with the pthread_mutex_t
wrapper removed:

https://github.com/jhi/clang-thread-safety-analysis-for-c.git

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-6-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

async: Register/unregister aiocontext in graph lock list

Add/remove the AioContext in aio_context_list in graph-lock.c when it is
created/destroyed. This allows using the graph locking operations from
this AioContext.

In order to allow linking util/async.c with binaries that don't include
the block layer, introduce stubs for (un)register_aiocontext().

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-5-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

graph-lock: Implement guard macros

Similar to the implementation in lockable.h, implement macros to
automatically take and release the rdlock.

Create the empty GraphLockable and GraphLockableMainloop structs only to
use it as a type for G_DEFINE_AUTOPTR_CLEANUP_FUNC.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-4-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

graph-lock: Introduce a lock to protect block graph operations

Block layer graph operations are always run under BQL in the main loop.
This is proved by the assertion qemu_in_main_thread() and its wrapper
macro GLOBAL_STATE_CODE.

However, there are also concurrent coroutines running in other iothreads
that always try to traverse the graph. Currently this is protected
(among various other things) by the AioContext lock, but once this is
removed, we need to make sure that reads do not happen while modifying
the graph.

We distinguish between writer (main loop, under BQL) that modifies the
graph, and readers (all other coroutines running in various AioContext),
that go through the graph edges, reading ->parents and->children.

The writer (main loop) has "exclusive" access, so it first waits for any
current read to finish, and then prevents incoming ones from entering
while it has the exclusive access.

The readers (coroutines in multiple AioContext) are free to access the
graph as long the writer is not modifying the graph. In case it is, they
go in a CoQueue and sleep until the writer is done.

If a coroutine changes AioContext, the counter in the original and new
AioContext are left intact, since the writer does not care where the
reader is, but only if there is one.

As a result, some AioContexts might have a negative reader count, to
balance the positive count of the AioContext that took the lock.  This
also means that when an AioContext is deleted it may have a nonzero
reader count. In that case we transfer the count to a global shared
counter so that the writer is always aware of all readers.

Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-3-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: Factor out bdrv_drain_all_begin_nopoll()

Provide a separate function that just quiesces the users of a node to
prevent new requests from coming in, but without waiting for the already
in-flight I/O to complete.

This function can be used in contexts where polling is not allowed.

Signed-off-by: Kevin Wolf <kwolf@redhat.com>
Message-Id: <20221207131838.239125-2-kwolf@redhat.com>
Reviewed-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block/dirty-bitmap: convert coroutine-only functions to co_wrapper

bdrv_can_store_new_dirty_bitmap and bdrv_remove_persistent_dirty_bitmap
check if they are running in a coroutine, directly calling the
coroutine callback if it's the case.
Except that no coroutine calls such functions, therefore that check
can be removed, and function creation can be offloaded to
c_w.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20221128142337.657646-15-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: convert bdrv_create to co_wrapper

This function is never called in coroutine context, therefore
instead of manually creating a new coroutine, delegate it to the
block-coroutine-wrapper script, defining it as co_wrapper.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20221128142337.657646-14-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block-coroutine-wrapper.py: support also basic return types

Extend the regex to cover also return type, pointers included.
This implies that the value returned by the function cannot be
a simple "int" anymore, but the custom return type.
Therefore remove poll_state->ret and instead use a per-function
custom "ret" field.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20221128142337.657646-13-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block-coroutine-wrapper.py: support functions without bs arg

Right now, we take the first parameter of the function to get the
BlockDriverState to pass to bdrv_poll_co(), that internally calls
functions that figure in which aiocontext the coroutine should run.

However, it is useless to pass a bs just to get its own AioContext,
so instead pass it directly, and default to the main loop if no
BlockDriverState is passed as parameter.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20221128142337.657646-12-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block-coroutine-wrapper.py: introduce co_wrapper

This new annotation starts just a function wrapper that creates
a new coroutine. It assumes the caller is not a coroutine.
It will be the default annotation to be used in the future.

This is much better as c_w_mixed, because it is clear if the caller
is a coroutine or not, and provides the advantage of automating
the code creation. In the future all c_w_mixed functions will be
substituted by co_wrapper.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20221128142337.657646-11-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: rename generated_co_wrapper in co_wrapper_mixed

In preparation to the incoming new function specifiers,
rename g_c_w with a more meaningful name and document it.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20221128142337.657646-10-eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: bdrv_create_file is a coroutine_fn

It is always called in coroutine_fn callbacks, therefore
it can directly call bdrv_co_create().

Rename it to bdrv_co_create_file too.

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20221128142337.657646-9-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>

block: distinguish between bdrv_create running in coroutine and not

Call two different functions depending on whether bdrv_create
is in coroutine or not, following the same pattern as
generated_co_wrapper functions.

This allows to also call the coroutine function directly,
without using CreateCo or relying in bdrv_create().

Signed-off-by: Emanuele Giuseppe Esposito <eesposit@redhat.com>
Reviewed-by: Kevin Wolf <kwolf@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@yandex-team.ru>
Message-Id: <20221128142337.657646-8-eesposit@redhat.com>
Signed-off-by: Kevin Wolf <kwolf@redhat.com>