Re: [RFC] generic device DMA implementation

From: James Bottomley (James.Bottomley@SteelEye.com)
Date: Fri Dec 06 2002 - 17:48:57 EST


davem@redhat.com said:
> It's like adding a new system call, and the same arguments apply.

> I don't want a 'flags' thing, because that tends to be the action
> which opens the flood gates for putting random feature-of-the-day new
> bits.

I did think of this. The flags are enums in include/linux/dma-mapping.h In
theory they can't be hijacked by an architecture without either changing this
global header or exciting compiler warnings.

However, I can only see their being two types of drivers: those which do all
the sync points and those which don't do any, so I can't see any reason for
there to be any more than two such flags.

I also want an active discouragement from using the may return inconsistent
API, and I think, given the general programmer predisposition not to want to
type, that a long flag name (or a long routine name) does this.

I just don't like API names that look like

dma_alloc_may_be_inconsistent()

but if that's what it takes, I'll do it

James

-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/



This archive was generated by hypermail 2b29 : Sat Dec 07 2002 - 22:00:28 EST