On 22/01/2026 20:30, Ackerley Tng wrote:
Nikita Kalyazin <[email protected]> writes:
[...snip...]
@@ -533,6 +580,8 @@ static void kvm_gmem_free_folio(struct folio *folio)
kvm_pfn_t pfn = page_to_pfn(page);
int order = folio_order(folio);
+ kvm_gmem_folio_restore_direct_map(folio);
+
I can't decide if the kvm_gmem_folio_no_direct_map(folio) should be in
the caller or within kvm_gmem_folio_restore_direct_map(), since this
time it's a folio-specific property being checked.
I'm tempted to keep it similar to the kvm_gmem_folio_zap_direct_map()
case. How does the fact it's a folio-speicific property change your
reasoning?
This is good too:
if (kvm_gmem_folio_no_direct_map(folio))
kvm_gmem_folio_restore_direct_map(folio)
It turns out we can't do that because folio->mapping is gone by the time
filemap_free_folio() is called so we can't inspect the flags. Are you
ok with only having this check when zapping (but not when restoring)?
Do you think we should add a comment saying it's conditional here?
I thought kvm_gmem_folio_no_direct_map() only reads folio->private,
which I think should still be there at the point of
filemap_free_folio().
Oh, I misread your last reply. What you're proposing would work indeed.
[...snip...]
