qdev: Replace no_user by cannot_instantiate_with_device_add_yet

In an ideal world, machines can be built by wiring devices together
with configuration, not code.  Unfortunately, that's not the world we
live in right now.  We still have quite a few devices that need to be
wired up by code.  If you try to device_add such a device, it'll fail
in sometimes mysterious ways.  If you're lucky, you get an
unmysterious immediate crash.

To protect users from such badness, DeviceClass member no_user used to
make device models unavailable with -device / device_add, but that
regressed in commit 18b6dad.  The device model is still omitted from
help, but is available anyway.

Attempts to fix the regression have been rejected with the argument
that the purpose of no_user isn't clear, and it's prone to misuse.

This commit clarifies no_user's purpose.  Anthony suggested to rename
it cannot_instantiate_with_device_add_yet_due_to_internal_bugs, which
I shorten somewhat to keep checkpatch happy.  While there, make it
bool.

Every use of cannot_instantiate_with_device_add_yet gets a FIXME
comment asking for rationale.  The next few commits will clean them
all up, either by providing a rationale, or by getting rid of the use.

With that done, the regression fix is hopefully acceptable.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
sysbus: Set cannot_instantiate_with_device_add_yet

device_add plugs devices into suitable bus.  For "real" buses, that
actually connects the device.  For sysbus, the connections need to be
made separately, and device_add can't do that.  The device would be
left unconnected, and could not possibly work.

Quite a few, but not all sysbus devices already set
cannot_instantiate_with_device_add_yet in their class init function.

Set it in their abstract base's class init function
sysbus_device_class_init(), and remove the now redundant assignments
from device class init functions.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
cpu: Document why cannot_instantiate_with_device_add_yet

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
apic: Document why cannot_instantiate_with_device_add_yet

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
pci-host: Consistently set cannot_instantiate_with_device_add_yet

Many PCI host bridges consist of a sysbus device and a PCI device.
You need both for the thing to work.  Arguably, these bridges should
be modelled as a single, composite devices instead of pairs of
seemingly independent devices you can only use together, but we're not
there, yet.

Since the sysbus part can't be instantiated with device_add, yet,
permitting it with the PCI part is useless.  We shouldn't offer
useless options to the user, so let's set
cannot_instantiate_with_device_add_yet for them.

It's already set for Bonito, Grackle, i440FX and Raven.  Document why.

Set it for the others: dec-21154, e500-host-bridge, gt64120_pci, mch,
pbm-pci, ppc4xx-host-bridge, sh_pci_host, u3-agp, uni-north-agp,
uni-north-internal-pci, uni-north-pci, and versatile_pci_host.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
ich9: Document why cannot_instantiate_with_device_add_yet

An ICH9 southbridge contains several PCI devices, some of them with
multiple functions.  We model each function as a separate qdev.  Two
of them need some special wiring set up in pc_q35_init() to work: the
LPC controller at 00:1f.0, and the SMBus controller at 00:1f.3.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
piix3 piix4: Clean up use of cannot_instantiate_with_device_add_yet

A PIIX3/PIIX4 southbridge has multiple functions.  We model each
function as a separate qdev.  Two of them need some special wiring set
up in pc_init1() or mips_malta_init() to work: the ISA bridge at 01.0,
and the SMBus controller at 01.3.

The IDE controller at 01.1 (piix3-ide, piix3-ide-xen, piix4-ide) has
always had cannot_instantiate_with_device_add_yet set, but there is no
obvious reason why device_add could not work for them.  Drop it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
vt82c686: Clean up use of cannot_instantiate_with_device_add_yet

A VT82C686B southbridge has multiple functions.  We model each
function as a separate qdev.  One of them need some special wiring set
up in mips_fulong2e_init() to work: the ISA bridge at 05.0.

The IDE controller at 05.1 (via-ide) has always had
cannot_instantiate_with_device_add_yet set, but there is no obvious
reason why device_add could not work for them.  Drop it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Andreas Färber <afaerber@suse.de>
isa: Clean up use of cannot_instantiate_with_device_add_yet

Drop it when there's no obvious reason why device_add could not work.
Else keep and document why.

* isa-fdc: drop

* i8042: drop, even though its I/O base is hardcoded (because you
  could conceivably still add one to a board that has none), and even
  though PC board code wires up the A20 line (because that wiring is
  optional)

* port92: keep because it needs additional wiring by port92_init()

* mc146818rtc: keep because it needs to be wired up by rtc_init()

* m48t59_isa: keep because needs to be wired up by m48t59_init_isa()

* isa-pit, kvm-pit: keep (in their abstract base pic-common) because
  the PIT needs additional wiring by board code, depending on HPET
  presence

* pcspk: keep because of pointer property pit, and because realize
  sets global pcspk_state

* vmmouse: keep because of pointer property ps2_mouse

* vmport: keep because realize sets global port_state

* isa-i8259, kvm-i8259: keep (in their abstract base pic-common),
  because the PICs' IRQ input lines are set up by board code, and the
  wiring of the slave to the master is hard-coded in device model code

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
qdev: Do not let the user try to device_add when it cannot work

Such devices have always been unavailable and omitted from the list of
available devices shown by device_add help.  Until commit 18b6dad
silently broke the former, setting up nasty traps for unwary users,
like this one:

    $ qemu-system-x86_64 -nodefaults -monitor stdio -display none
    QEMU 1.6.50 monitor - type 'help' for more information
    (qemu) device_add apic
    Segmentation fault (core dumped)

I call that a regression.  Fix it.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Marcel Apfelbaum <marcel.a@redhat.com>
Signed-off-by: Andreas Färber <afaerber@suse.de>
hw/arm/highbank: Simplify code (memory region in device state)

The memory region can be included by value instead of by reference in the
device state.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Peter Crosthwaite <peter.crosthwaite@xilinx.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
openrisc: Fix spelling in comment (transaltion -> translation)

I also removed two hyphens in the same comment.

Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Jia Liu <proljc@gmail.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
misc: Use macro ARRAY_SIZE where possible

This improves readability and simplifies the code.

Cc: Anthony Liguori <aliguori@amazon.com>
Cc: Gerd Hoffmann <kraxel@redhat.com>
Cc: Stefan Hajnoczi <stefanha@redhat.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
ui/cocoa: Use macro ARRAY_SIZE where possible

This improves readability and simplifies the code.

Cc: Andreas Färber <andreas.faerber@web.de>
Cc: Anthony Liguori <aliguori@amazon.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
exynos4210: Use macro ARRAY_SIZE where possible

This improves readability and simplifies the code.

Cc: Dmitry Solodkiy <d.solodkiy@samsung.com>
Cc: Evgeny Voevodin <e.voevodin@samsung.com>
Cc: Igor Mitsyanko <i.mitsyanko@gmail.com>
Cc: Maksim Kozlov <m.kozlov@samsung.com>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
linux-user: Use macro TARGET_NSIG_WORDS where possible

This improves readability and simplifies the code.

Cc: Riku Voipio <riku.voipio@iki.fi>
Signed-off-by: Stefan Weil <sw@weilnetz.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
x86: only allow real mode to access 32bit without LMA

When we're running in non-64bit mode with qemu-system-x86_64 we can
still end up with virtual addresses that are above the 32bit boundary
if a segment offset is set up.

GNU Hurd does exactly that. It sets the segment offset to 0x80000000 and
puts its EIP value to 0x8xxxxxxx to access low memory.

This doesn't hit us when we enable paging, as there we just mask away the
unused bits. But with real mode, we assume that vaddr == paddr which is
wrong in this case. Real hardware wraps the virtual address around at the
32bit boundary. So let's do the same.

This fixes booting GNU Hurd in qemu-system-x86_64 for me.

Reported-by: Michael Tokarev <mjt@tls.msk.ru>
Signed-off-by: Alexander Graf <agraf@suse.de>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
vl: make boot_strict variable static (not used outside vl.c)

Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
Reviewed-by: Amos Kong <akong@redhat.com>
fix -boot strict regressed in commit 6ef4716

Commit 6ef4716 cleaned up parsing of -boot option argument, but
accidentally dropped parameter strict.  It should have been updated
exactly like parameter menu. Do that.

Signed-off-by: Amos Kong <akong@redhat.com>
Reviewed-by: Markus Armbruster <armbru@redhat.com>
Signed-off-by: Michael Tokarev <mjt@tls.msk.ru>
target-arm: A64: add support for ld/st pair

This patch support the basic load and store pair instructions and
includes the generic helper functions:

  * do_gpr_st()
  * do_fp_st()
  * do_gpr_ld()
  * do_fp_ld()
  * read_cpu_reg_sp()
  * gen_check_sp_alignment()

The last function gen_check_sp_alignment() is a NULL op currently but
put in place to make it easy to add SP alignment checking later.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>