> Where does the device come from? What device is it? At the higher level someone passed us a device and some mappings and function methods and said "this is an IDE controller" > Is that known already? The core code has no idea or interest in where it came from. > But at least on x86-64 the device is likely DMA capable. At least > PCMCIA usually is. Near all devices are DMA capable, except perhaps PCMCIA usally isn't. > So if I return NULL then either a really DMA capable device will > not work. Or you got a real oddball device that you shouldn't have gotten > in the first place. What about other platforms ? I don't want libata to have #ifdef CONFIG_X86_64 /* this platform is different) if (hack-around-in-dev-struct()) return NULL; #endif All I want is This is a device, the caller has said it may be DMA capable dma_alloc_coherent NULL. ok in this situation it isn't I don't want to know about arch internals. I don't want to know about platform specific DMA rules. I just want to be able to ask for DMA and get told yes or no. Oops is not a useful error return. - To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
