Re: [Qemu-devel] [PATCH 1/2] ide: core: add cleanup function

[Li Qiang]

Hello John, Paolo,

2017-03-01 8:47 GMT+08:00 John Snow <address@hidden>:

>
>
> On 02/09/2017 02:04 AM, Li Qiang wrote:
> > As the pci ahci can be hotplug and unplug, in the ahci unrealize
> > function it should free all the resource once allocated in the
> > realized function. This patch adds two cleanup function.
> >
>
> So, the peculiarities of the current arrangement of QDEV realization and
> unrealization is a bit of a mystery to me, so I'm hoping my suggestions
> here make sense.
>
> > Signed-off-by: Li Qiang <address@hidden>
> > ---
> >  hw/ide/core.c             | 21 +++++++++++++++++++++
> >  include/hw/ide/internal.h |  2 ++
> >  2 files changed, 23 insertions(+)
> >
> > diff --git a/hw/ide/core.c b/hw/ide/core.c
> > index 43709e5..8fe5896 100644
> > --- a/hw/ide/core.c
> > +++ b/hw/ide/core.c
> > @@ -2586,6 +2586,13 @@ void ide_register_restart_cb(IDEBus *bus)
> >      }
> >  }
> >
> > +void ide_unregister_restart_cb(IDEBus *bus)
> > +{
> > +    if (bus->dma->ops->restart_dma) {
> > +        qemu_del_vm_change_state_handler(bus->vmstate);
> > +    }
> > +}
> > +
>
> This works perfectly well, though I think the function is named
> incorrectly -- this should be an AHCI function, as it is AHCI's job to
> unregister the IDEBus it created (not IDE's -- the bus belongs to the
> HBA, not the IDE device.)
>
> However, we DO have the IDEBus unrealize code in qdev.c that should be
> handling this for us. Can we rename this function and just have it set
> the "realized" property of the IDEBus to false to handle this cleanup
> for us?
>
> I'm not well versed in qdev code management, but it definitely feels
> wrong to have the cleanup in two places.
>

 Agree, but I'm not familiar with qdev too, that's why we need Paolo's help.

@Paolo,
Could you please have a look at this issue?


> >  static IDEDMA ide_dma_nop = {
> >      .ops = &ide_dma_nop_ops,
> >      .aiocb = NULL,
> > @@ -2603,6 +2610,20 @@ void ide_init2(IDEBus *bus, qemu_irq irq)
> >      bus->dma = &ide_dma_nop;
> >  }
> >
> > +void ide_exit(IDEBus *bus)
> > +{
> > +    int i;
> > +
> > +    for (i = 0; i < 2; i++) {
> > +        IDEState *s = &bus->ifs[i];
> > +
> > +        timer_del(s->sector_write_timer);
> > +        timer_free(s->sector_write_timer);
> > +        qemu_vfree(s->smart_selftest_data);
> > +        qemu_vfree(s->io_buffer);
>
> I would prefer a function that cleans up a single IDE device, and the
> caller (which has knowledge of the HBA and the buses it owns) loops as
> appropriate. (In this case, ahci_uninit or ahci_unrealize or whichever.)
>
> It's correct otherwise, though.
>
> > +    }
> > +}
> > +
> >  static const MemoryRegionPortio ide_portio_list[] = {
> >      { 0, 8, 1, .read = ide_ioport_read, .write = ide_ioport_write },
> >      { 0, 1, 2, .read = ide_data_readw, .write = ide_data_writew },
> > diff --git a/include/hw/ide/internal.h b/include/hw/ide/internal.h
> > index 88dc118..09b0404 100644
> > --- a/include/hw/ide/internal.h
> > +++ b/include/hw/ide/internal.h
> > @@ -607,8 +607,10 @@ int ide_init_drive(IDEState *s, BlockBackend *blk,
> IDEDriveKind kind,
> >                     uint32_t cylinders, uint32_t heads, uint32_t secs,
> >                     int chs_trans);
> >  void ide_init2(IDEBus *bus, qemu_irq irq);
> > +void ide_exit(IDEBus *bus);
> >  void ide_init_ioport(IDEBus *bus, ISADevice *isa, int iobase, int
> iobase2);
> >  void ide_register_restart_cb(IDEBus *bus);
> > +void ide_unregister_restart_cb(IDEBus *bus);
> >
> >  void ide_exec_cmd(IDEBus *bus, uint32_t val);
> >
> >
>