[RFC PATCH 03/18] fs/dax: use ptdesc in dax_pmd_load_hole

[alexs]

From: Alex Shi <alexs@xxxxxxxxxx>

Since we have ptdesc struct now, better to use replace pgtable_t, aka
'struct page *'.
It's a prepare for return ptdesc pointer in pte_alloc_one series
function.

Signed-off-by: Alex Shi <alexs@xxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Cc: nvdimm@xxxxxxxxxxxxxxx
Cc: linux-fsdevel@xxxxxxxxxxxxxxx
Cc: Christian Brauner <brauner@xxxxxxxxxx>
Cc: Alexander Viro <viro@xxxxxxxxxxxxxxxxxx>
Cc: Jan Kara <jack@xxxxxxx>
Cc: Matthew Wilcox <willy@xxxxxxxxxxxxx>
Cc: Dan Williams <dan.j.williams@xxxxxxxxx>
---
 fs/dax.c | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/fs/dax.c b/fs/dax.c
index becb4a6920c6..6f7cea248206 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -1206,7 +1206,7 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
 	unsigned long pmd_addr = vmf->address & PMD_MASK;
 	struct vm_area_struct *vma = vmf->vma;
 	struct inode *inode = mapping->host;
-	pgtable_t pgtable = NULL;
+	struct ptdesc *ptdesc = NULL;
 	struct folio *zero_folio;
 	spinlock_t *ptl;
 	pmd_t pmd_entry;
@@ -1222,8 +1222,8 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
 				  DAX_PMD | DAX_ZERO_PAGE);
 
 	if (arch_needs_pgtable_deposit()) {
-		pgtable = pte_alloc_one(vma->vm_mm);
-		if (!pgtable)
+		ptdesc = page_ptdesc(pte_alloc_one(vma->vm_mm));
+		if (!ptdesc)
 			return VM_FAULT_OOM;
 	}
 
@@ -1233,8 +1233,8 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
 		goto fallback;
 	}
 
-	if (pgtable) {
-		pgtable_trans_huge_deposit(vma->vm_mm, vmf->pmd, pgtable);
+	if (ptdesc) {
+		pgtable_trans_huge_deposit(vma->vm_mm, vmf->pmd, ptdesc_page(ptdesc));
 		mm_inc_nr_ptes(vma->vm_mm);
 	}
 	pmd_entry = mk_pmd(&zero_folio->page, vmf->vma->vm_page_prot);
@@ -1245,8 +1245,8 @@ static vm_fault_t dax_pmd_load_hole(struct xa_state *xas, struct vm_fault *vmf,
 	return VM_FAULT_NOPAGE;
 
 fallback:
-	if (pgtable)
-		pte_free(vma->vm_mm, pgtable);
+	if (ptdesc)
+		pte_free(vma->vm_mm, ptdesc_page(ptdesc));
 	trace_dax_pmd_load_hole_fallback(inode, vmf, zero_folio, *entry);
 	return VM_FAULT_FALLBACK;
 }
-- 
2.43.0