[PATCH v3 1/3] x86/mm/pat: Convert pte code to use ptdescs

["Vishal Moola (Oracle)" <vishal.moola@gmail.com>]

In order to separately allocate ptdescs from pages, we need all allocation
and free sites to use the appropriate functions. Convert these pte
allocation/free sites to use ptdescs.

Signed-off-by: Vishal Moola (Oracle) <vishal.moola@gmail.com>
---
 arch/x86/mm/pat/set_memory.c | 15 +++++++++------
 1 file changed, 9 insertions(+), 6 deletions(-)

diff --git a/arch/x86/mm/pat/set_memory.c b/arch/x86/mm/pat/set_memory.c
index 6c6eb486f7a6..f9f9d4ca8e71 100644
--- a/arch/x86/mm/pat/set_memory.c
+++ b/arch/x86/mm/pat/set_memory.c
@@ -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);
+	pagetable_free(virt_to_ptdesc((void *)pte));
 	return true;
 }
 
@@ -1537,12 +1537,15 @@ 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_ptdesc(pmd_t *pmd)
 {
-	pte_t *pte = (pte_t *)get_zeroed_page(GFP_KERNEL);
-	if (!pte)
+	pte_t *pte;
+	struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL | __GFP_ZERO, 0);
+
+	if (!ptdesc)
 		return -1;
 
+	pte = (pte_t *) ptdesc_address(ptdesc);
 	set_pmd(pmd, __pmd(__pa(pte) | _KERNPG_TABLE));
 	return 0;
 }
@@ -1600,7 +1603,7 @@ 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_ptdesc(pmd))
 				return -1;
 
 		populate_pte(cpa, start, pre_end, cur_pages, pmd, pgprot);
@@ -1641,7 +1644,7 @@ 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_ptdesc(pmd))
 				return -1;
 
 		populate_pte(cpa, start, end, num_pages - cur_pages,
-- 
2.52.0