[PATCH v5 2/4] x86/mm/pat: Convert pte code to use ptdescs

From: Vishal Moola (Oracle)

Date: Wed Feb 11 2026 - 14:53:21 EST


We need all allocation and free sites to use the ptdesc APIs in order to
allocate them separately from regular pages. Convert these pte
allocation/free sites to use ptdescs.

Also, rename *_pte_page() functions to *_pte(). Rename them now to avoid
any confusion later. Eventually these allocations will be backed by a
ptdesc not a page, but that's not important to callers either.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx>
---
arch/x86/mm/pat/set_memory.c | 14 +++++++-------
1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index 6c6eb486f7a6..04eae65aedfc 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -1400,7 +1400,7 @@ static int collapse_large_pages(unsigned long addr, struct list_head *pgtables)
return collapsed;
}

-static bool try_to_free_pte_page(pte_t *pte)
+static bool try_to_free_pte(pte_t *pte)
{
int i;

@@ -1408,7 +1408,7 @@ static bool try_to_free_pte_page(pte_t *pte)
if (!pte_none(pte[i]))
return false;

- free_page((unsigned long)pte);
+ pgtable_free_addr(pte);
return true;
}

@@ -1435,7 +1435,7 @@ static bool unmap_pte_range(pmd_t *pmd, unsigned long start, unsigned long end)
pte++;
}

- if (try_to_free_pte_page((pte_t *)pmd_page_vaddr(*pmd))) {
+ if (try_to_free_pte((pte_t *)pmd_page_vaddr(*pmd))) {
pmd_clear(pmd);
return true;
}
@@ -1537,9 +1537,9 @@ static void unmap_pud_range(p4d_t *p4d, unsigned long start, unsigned long end)
*/
}

-static int alloc_pte_page(pmd_t *pmd)
+static int alloc_pte(pmd_t *pmd)
{
- pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
+ pte_t *pte = pgtable_alloc_addr(GFP_KERNEL, 0);
if (!pte)
return -1;

@@ -1600,7 +1600,7 @@ static long populate_pmd(struct cpa_data *cpa,
*/
pmd = pmd_offset(pud, start);
if (pmd_none(*pmd))
- if (alloc_pte_page(pmd))
+ if (alloc_pte(pmd))
return -1;

populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot);
@@ -1641,7 +1641,7 @@ static long populate_pmd(struct cpa_data *cpa,
if (start < end) {
pmd = pmd_offset(pud, start);
if (pmd_none(*pmd))
- if (alloc_pte_page(pmd))
+ if (alloc_pte(pmd))
return -1;

populate_pte(cpa, start, end, num_pages - cur_pages,
--
2.52.0