Matthew Wilcox <willy@xxxxxxxxxxxxx> writes:
> On Wed, Jan 24, 2024 at 11:20:23AM +0000, Alice Ryhl wrote:
>> +impl Page {
>> + /// Allocates a new set of contiguous pages.
>> + pub fn new() -> Result<Self, AllocError> {
>> + // SAFETY: These are the correct arguments to allocate a single page.
>> + let page = unsafe {
>> + bindings::alloc_pages(
>> + bindings::GFP_KERNEL | bindings::__GFP_ZERO | bindings::__GFP_HIGHMEM,
>> + 0,
>> + )
>> + };
>
> This feels too Binder-specific to be 'Page'. Pages are not necessarily
> allocated with GFP_HIGHMEM, nor are they necessarily zeroed. Maybe you
> want a BinderPage type?
Rust null block uses the same definition of these flags [1], so there is
at least that synergy.
I feel like we had the discussion of the flags before, although I can't
find the thread now. I think the conclusion was that we fix them until
we have code that need to actually change them (as to not add dead
code).
BR Andreas
[1] https://github.com/metaspace/linux/blob/702026e6645193fc89b7d55e00dac75fd492bfb8/rust/kernel/pages.rs#L28
