bus: Make BUS_TRANSLATE_RESOURCE behave more like other bus methods

[markj]

Summary

• Return an errno value upon failure, instead of 1.
• Provide a bus_translate_resource() wrapper.
• Implement the generic version, which traverses the hierarchy until a bus driver with a non-trivial implementation is found, in subr_bus.c like other similar default implementations.
• Make ofw_pcib_translate_resource() return an error if a matching PCI address range is not found.
• Make generic_pcie_translate_resource_common() return an int instead of a bool. Fix up callers.

No functional change intended.

[jhb]

Thanks

[imp]

sys/dev/ofw/ofw_pcib.c

489

I'd kill this.

514

and instead put *newstart = start; return (0); here. There's no locking issues to worry about for the single in single out pattern, nor are there likely to be.

521

and kill this else and just return ENOENT always.

sys/dev/pci/pci_host_generic.c

426

shouldn't this be != 0? If it was unsuccessful, we want to print the error message, no?

480

Do you need to undo the effects of rman_activate_resource() above here?

[imp]

sys/dev/pci/pci_host_generic.c

426

The original looks wrong as well if translate_resource returned true for an error, so either it's wrong or the description in the review is wrong.

[markj]

sys/dev/pci/pci_host_generic.c

426

This should be != 0, thanks. The confusing bit is that generic_pcie_translate_resource_common() returned a bool, "found", and generic_pcie_translate_resource() inverted the result. The code was right before.

480

Hmm, probably yes. In practice I don't think this error can happen.

[markj]

Handle Warner's notes:

• Simplify ofw_pcib_translate_resource()
• Fix an inverted test
• Deactivate the resource in generic_pcie_activate_resource() if generic_pcie_translate_resource_common() fails

[imp]

Thanks! Looks good to go now.