[+cc Martin] On Thu, Apr 2, 2015 at 4:28 PM, Michael S. Tsirkin <mst@xxxxxxxxxx> wrote: > On Thu, Apr 02, 2015 at 03:53:47PM -0500, Bjorn Helgaas wrote: >> On Mon, Mar 30, 2015 at 01:33:28PM +0200, Michael S. Tsirkin wrote: >> > The basic class ID macros in pci_ids.h are pretty useful for userspace >> > using the pci sysfs interface, and they aren't fundamentally different >> > from the constants in pci_regs.h - both are defined in the >> > pci spec. >> > >> > At the moment userspace is forced to duplicate these macros >> > (e.g. QEMU does this, so do seabios, gpxe, and others), it is better to >> > expose them in /usr/include/linux/pci_ids.h so everyone can just include >> > this header. >> >> I agree that it would be nice for applications to get these definitions >> from a single place, but I'm not sure that include/uapi/linux/pci_ids.h >> needs to be that place. >> >> These constants are just copies of what's in the spec, and I don't think >> you're suggesting that the constants are necessary to use a kernel API. >> >> I know the kernel does provide access to values via sysfs "class" files, >> but the kernel is just passing the values through from the hardware. >> That's analogous to reading the class with setpci, and I don't think it >> leads to a requirement that the kernel export all the information about how >> to interpret the class values. >> >> I haven't looked at libpci or libudev, but it sounds like you think those >> are not good solutions. Is that because they don't currently have this >> information? People don't want to add dependencies on them? > > People don't want to add dependencies on them. Why not? I'm not a user-space programmer, so it's not obvious to me what the problems with adding a dependency are. If a package provides functionality you want, it seems like a *good* thing to use it and depend on it rather than reimplementing the functionality yourself. The /usr/include/pci/header.h supplied by libpci-dev (on Ubuntu) looks like it has most or all of the constants you want. Bjorn -- To unsubscribe from this list: send the line "unsubscribe linux-api" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
