On Tue, Feb 17, 2015 at 11:41:49AM -0800, Jake Oshins wrote: > This patch adds some wrapper functions in the pnp layer. The intent is > to allow memory address space claims by devices which are descendants > (a child or grandchild of) a device which is already part of the pnp > layer. This allows a device to make a resource claim that doesn't > conflict with its "aunts" and "uncles." > > This is useful in a Hyper-V VM because some paravirtual "devices" need > memory-mapped I/O space, and their aunts and uncles can be PCI devices. > Furthermore, the hypervisor expresses the possible memory address > combinations for the devices in the VM through the ACPI namespace. > The paravirtual devices need to suballocate from the ACPI nodes, and > they need to avoid conflicting with choices that the Linux PCI code > makes about the PCI devices in the VM. > > It might seem like this should be done in the platform layer rather > than the pnp layer, but the platform layer assumes that the > configuration of the devices in the machine are static, or at least > expressed by firmware in a static fashion. The nature of a Hyper-V > VM is that new devices can be added while the machine is running, > and the potential configurations for them are expressed as part of > the paravirtual communications channel. This much more naturally > aligns with the pnp layer. > > Signed-off-by: Jake Oshins <ja...@microsoft.com> > --- > drivers/pnp/Makefile | 2 +- > drivers/pnp/base.h | 2 + > drivers/pnp/core.c | 1 + > drivers/pnp/descendant.c | 117 > +++++++++++++++++++++++++++++++++++++++++++++++ > include/linux/pnp.h | 23 ++++++++++ > 5 files changed, 144 insertions(+), 1 deletion(-) > create mode 100644 drivers/pnp/descendant.c
At first glance, this looks ok. Does it change the sysfs layout of hyperv devices? also, I'd like KY to sign-off on it, verifying that he at least tested the series and it works for him. thanks, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
