On Sat, Mar 24, 2012 at 12:15:59PM -0700, H. Peter Anvin wrote: > On 03/24/2012 11:42 AM, Konrad Rzeszutek Wilk wrote: > > > > Probably should also have: > > u32 version; > > > > in case we decide to expand this structure in the future, and: > >> u32 type; /* 1 = file data, 2 = ACPI, 3 = microcode... */ > >> u32 length; /* Length of data object */ > >> }; > > > > and encapsulate the whole thing in a 4K union? > > > > For "version" you'd have to define what happens if you see a version > number you don't recognize, and why that is in any way better than > changing the magic number or the type. It is something that people like > to throw in without thinking about it, and that is a mistake. I was thinking of interface version. So the first would be 1, and if there are extensions (so version 2 for example), it should support 1 and 2. The idea is to expand past the structure with newer additions without breaking the binary interface. > > Forcing everything to be page-aligned may be a good idea, although that > assumes all bootloaders actually align them that way... Oh, and be 4K. > > > > > Perhaps the header should be in big-endian (that is the same as the network > > byte order, right?) and each sub-type can define its own endian? > > > > The content of the encapsulation is its own thing; it will be different > for different types as most of them already > > -hpa > > -- > H. Peter Anvin, Intel Open Source Technology Center > I work for Intel. I don't speak on their behalf. -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
