Hi Weiping, > currently, there are four combinations as following: "write through", > "none", "write back", "write back, no read (daft)" > > cache_type can control both write and read cache, but for "write > through" and "write back" we can not know clearly how to control the > read cache.
That's what I meant by using the term "arcane" and alluding to the fact that this interface is not well enough documented. > I prefer use words like"w0r1", "w0r0", "w1r1", "w1r0", that "1" means > enable, "0" means disable. The user know clearly what they are doing > when typing these short words. We can't change the existing interface without breaking stuff. We can entertain adding stuff, but I do think that a better solution is to document what's there so the effect of echoing each of the following strings becomes crystal clear: static const char *sd_cache_types[] = { "write through", "none", "write back", "write back, no read (daft)" }; I would also like to see the "temporary" string documented. -- Martin K. Petersen Oracle Linux Engineering