Re: [PATCH v3 04/11] vpci/header: Add and remove register handlers dynamically

[Jan Beulich <jbeulich@xxxxxxxx>]

On 30.09.2021 09:52, Oleksandr Andrushchenko wrote:
> @@ -445,14 +456,25 @@ static void rom_write(const struct pci_dev *pdev, 
> unsigned int reg,
>          rom->addr = val & PCI_ROM_ADDRESS_MASK;
>  }
>  
> -static int add_bar_handlers(const struct pci_dev *pdev)
> +static void guest_rom_write(const struct pci_dev *pdev, unsigned int reg,
> +                            uint32_t val, void *data)
> +{
> +}
> +
> +static uint32_t guest_rom_read(const struct pci_dev *pdev, unsigned int reg,
> +                               void *data)
> +{
> +    return 0xffffffff;
> +}
> +
> +static int add_bar_handlers(const struct pci_dev *pdev, bool is_hwdom)

I remain unconvinced that this boolean is the best way to go here, but
I'll leave the decision there to Roger. Just a couple of nits:

> @@ -593,6 +625,30 @@ static int init_bars(struct pci_dev *pdev)
>  }
>  REGISTER_VPCI_INIT(init_bars, VPCI_PRIORITY_MIDDLE);
>  
> +#ifdef CONFIG_HAS_VPCI_GUEST_SUPPORT
> +int vpci_bar_add_handlers(const struct domain *d, const struct pci_dev *pdev)
> +{
> +    int rc;
> +
> +    /* Remove previously added registers. */
> +    vpci_remove_device_registers(pdev);
> +
> +    rc = add_bar_handlers(pdev, is_hardware_domain(d));
> +    if ( rc )
> +        gdprintk(XENLOG_ERR,
> +                 "%pp: failed to add BAR handlers for dom%pd: %d\n",

Only %pd please, as that already expands to d<num>.

> +                 &pdev->sbdf, d, rc);
> +    return rc;

Blank line please ahead of the main return statement of a function.

Jan