| From | Linus Torvalds <> | Date | Thu, 22 Nov 2018 08:50:47 -0800 | Subject | Re: remove the ->mapping_error method from dma_map_ops V2 |
| |
On Thu, Nov 22, 2018 at 6:03 AM Christoph Hellwig <hch@lst.de> wrote: > > The 0 return doesn't work for direct mappings that have ram at address > zero and a lot of IOMMUs that start allocating bus space from address > zero, so we can't consolidate on that, but I think we can move everyone > to all-Fs, which the patch here does.
Hmm. Maybe not limit it to just all ones, but actually use the (standard, for the kernel) IS_ERR_VALUE()?
That basically reserves the last 4095 values in an unsigned long for error values.
Then those functions could actually return *what* error they encountered, using just plain
return -ENOMEM;
or whatever?
Linus
|