On 26/03/2020 15:24, Alexandru Elisei wrote:
> During configuration of the BAR addresses, a Linux guest disables and
> enables access to I/O and memory space. When access is disabled, we don't
> stop emulating the memory regions described by the BARs. Now that we have
> callbacks for activating and deactivating emulation for a BAR region,
> let's use that to stop emulation when access is disabled, and
> re-activate it when access is re-enabled.
>
> Signed-off-by: Alexandru Elisei <alexandru.elisei@xxxxxxx>
Reviewed-by: Andre Przywara <andre.przywara@xxxxxxx>
Cheers,
Andre
> ---
> pci.c | 42 ++++++++++++++++++++++++++++++++++++++++++
> 1 file changed, 42 insertions(+)
>
> diff --git a/pci.c b/pci.c
> index 4ace190898f2..c2860e6707fe 100644
> --- a/pci.c
> +++ b/pci.c
> @@ -163,6 +163,42 @@ static struct ioport_operations pci_config_data_ops = {
> .io_out = pci_config_data_out,
> };
>
> +static void pci_config_command_wr(struct kvm *kvm,
> + struct pci_device_header *pci_hdr,
> + u16 new_command)
> +{
> + int i;
> + bool toggle_io, toggle_mem;
> +
> + toggle_io = (pci_hdr->command ^ new_command) & PCI_COMMAND_IO;
> + toggle_mem = (pci_hdr->command ^ new_command) & PCI_COMMAND_MEMORY;
> +
> + for (i = 0; i < 6; i++) {
> + if (!pci_bar_is_implemented(pci_hdr, i))
> + continue;
> +
> + if (toggle_io && pci__bar_is_io(pci_hdr, i)) {
> + if (__pci__io_space_enabled(new_command))
> + pci_hdr->bar_activate_fn(kvm, pci_hdr, i,
> + pci_hdr->data);
> + else
> + pci_hdr->bar_deactivate_fn(kvm, pci_hdr, i,
> + pci_hdr->data);
> + }
> +
> + if (toggle_mem && pci__bar_is_memory(pci_hdr, i)) {
> + if (__pci__memory_space_enabled(new_command))
> + pci_hdr->bar_activate_fn(kvm, pci_hdr, i,
> + pci_hdr->data);
> + else
> + pci_hdr->bar_deactivate_fn(kvm, pci_hdr, i,
> + pci_hdr->data);
> + }
> + }
> +
> + pci_hdr->command = new_command;
> +}
> +
> void pci__config_wr(struct kvm *kvm, union pci_config_address addr, void *data, int size)
> {
> void *base;
> @@ -188,6 +224,12 @@ void pci__config_wr(struct kvm *kvm, union pci_config_address addr, void *data,
> if (*(u32 *)(base + offset) == 0)
> return;
>
> + if (offset == PCI_COMMAND) {
> + memcpy(&value, data, size);
> + pci_config_command_wr(kvm, pci_hdr, (u16)value);
> + return;
> + }
> +
> bar = (offset - PCI_BAR_OFFSET(0)) / sizeof(u32);
>
> /*
>
