virtio_pci_legacy: Use the table BAR and PBA BAR from MSI-X cap

[khng300_gmail.com]

Summary

The MSI-X resource shouldn't be assumed to be always on BAR1.
The Virtio v1.1 Spec did not specify that MSI-X table and PBA BAR has to
be BAR1 either.

Reported by: Yuan Rui <[e-mail]>
MFC after: 2 weeks

[khng300_gmail.com]

@number201724_me.com Could you test this patch on FreeBSD 13 BETA2? Thanks.

[bryanv]

sys/dev/virtio/pci/virtio_pci_legacy.c

234

This error message isn't necessarily correct, and if the MSIX allocs fail, we don't release BAR 0 (both are existing issues before this change).

Moving the MSIX stuff out of vtpci_legacy_alloc_resources() and calling vtpci_legacy_setup_msix() from this function probably fits the existing flow the best, so we can jump to fail to do the cleanup.

[khng300_gmail.com]

• Moved virtio_legacy_setup_msix to virtio_legacy_attach
• Moved virtio_legacy_cleanup_msix to virtio_legacy_detach

[khng300_gmail.com]

Fix compilation.

[jhb]

I think this looks fine. Minor nit: I think we tend to use 'teardown' or 'free' more commonly in device drivers rather than 'cleanup'.

[number201724_me.com]

After testing, this patch runs normally on alibabacloud

[khng300_gmail.com]

Nit: naming

[khng300_gmail.com]

In D28817#647763, @jhb wrote:

I think this looks fine. Minor nit: I think we tend to use 'teardown' or 'free' more commonly in device drivers rather than 'cleanup'.

Changed to match our naming convention.