hyperv/vmbus: add new vmbus methods to support PCIe pass-through

[decui_microsoft.com]

Summary

The new methods will be used by the coming pcib driver.

[sepherosa_gmail.com]

sys/dev/hyperv/vmbus/vmbus_if.m

49 ↗

(On Diff #21876)

This replaced by:
vmbus_chan_guid_inst(vmbus_get_channel(dev))

[decui_microsoft.com]

sys/dev/hyperv/vmbus/vmbus_if.m

49 ↗

(On Diff #21876)

OK, will remove this method.

[decui_microsoft.com]

removed the get instance guid method, and moved the get_vcpu_id method to a separate patch (https://reviews.freebsd.org/D8410)

[sepherosa_gmail.com]

sys/dev/hyperv/vmbus/vmbus.c

47–52

Move sys/rman.h to the above inclusion group. Group machine/*.h together

59

Move this after "acpi_if.h" inclusion. Strip the blank line bewteen dev/pci/*.h and dev/acpica/acpivar.h

[decui_microsoft.com]

This new version addressed Sephe's comments.

[decui_microsoft.com]

I uploaded the new version to address the comments.

[sepherosa_gmail.com]

Ship it!

[jhb]

This looks fine. Note that there is some existing code this somewhat duplicates. For example, the ACPI Host-PCI bridge driver also parses _CRS to determine valid ranges. It uses the pcib_host_res_* API to add those ranges to a list that it then iterates on allocation requests. I'm not sure if does the same trick of preferring > 4G ranges for 64-bit BARs (though if pcib_host_res_*() would otherwise work for you I'd be fine with fixing it to do the same).

[sepherosa_gmail.com]

In D8409#175275, @jhb wrote:

This looks fine. Note that there is some existing code this somewhat duplicates. For example, the ACPI Host-PCI bridge driver also parses _CRS to determine valid ranges. It uses the pcib_host_res_* API to add those ranges to a list that it then iterates on allocation requests. I'm not sure if does the same trick of preferring > 4G ranges for 64-bit BARs (though if pcib_host_res_*() would otherwise work for you I'd be fine with fixing it to do the same).

Hmm, we probably can reuse the existing APIs, but do two pass decodes, the first pass adds the 64-bits BARs, the second one adds 32-bits BARs.

[decui_microsoft.com]

Hi jhb, Thanks for the suggestion! I'll update the patch with the pcib_host_res_* APIs.

[decui_microsoft.com]

In D8409#175368, @sepherosa_gmail.com wrote:

In D8409#175275, @jhb wrote:

This looks fine. Note that there is some existing code this somewhat duplicates. For example, the ACPI Host-PCI bridge driver also parses _CRS to determine valid ranges. It uses the pcib_host_res_* API to add those ranges to a list that it then iterates on allocation requests. I'm not sure if does the same trick of preferring > 4G ranges for 64-bit BARs (though if pcib_host_res_*() would otherwise work for you I'd be fine with fixing it to do the same).

Hmm, we probably can reuse the existing APIs, but do two pass decodes, the first pass adds the 64-bits BARs, the second one adds 32-bits BARs.

Good suggestion! I've made a patch with the 2-pass method. Will upload it shortly.

[decui_microsoft.com]

This new version addressed jhb and sephe's comments.