[PATCH 1/3] mm: generalize kernel PTE table allocation

[Muchun Song <songmuchun@bytedance.com>]

Architectures whose empty kernel PTE representation is not all zero must
initialize new kernel PTE tables. LoongArch therefore wraps
__pte_alloc_one_kernel() solely to call kernel_pte_init().

Call the architecture initialization hook from the generic allocator so
LoongArch can use it directly. The default hook is empty, so this does not
change other architectures.

Assisted-by: LLM
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
---
 arch/loongarch/include/asm/pgalloc.h | 11 -----------
 include/asm-generic/pgalloc.h        |  6 +++++-
 2 files changed, 5 insertions(+), 12 deletions(-)

diff --git a/arch/loongarch/include/asm/pgalloc.h b/arch/loongarch/include/asm/pgalloc.h
index 248f62d0b590..a3f93a8b58be 100644
--- a/arch/loongarch/include/asm/pgalloc.h
+++ b/arch/loongarch/include/asm/pgalloc.h
@@ -10,7 +10,6 @@
 
 #define __HAVE_ARCH_PMD_ALLOC_ONE
 #define __HAVE_ARCH_PUD_ALLOC_ONE
-#define __HAVE_ARCH_PTE_ALLOC_ONE_KERNEL
 #include <asm-generic/pgalloc.h>
 
 static inline void pmd_populate_kernel(struct mm_struct *mm,
@@ -45,16 +44,6 @@ extern void pagetable_init(void);
 
 extern pgd_t *pgd_alloc(struct mm_struct *mm);
 
-static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm)
-{
-	pte_t *pte = __pte_alloc_one_kernel(mm);
-
-	if (pte)
-		kernel_pte_init(pte);
-
-	return pte;
-}
-
 #define __pte_free_tlb(tlb, pte, address)	tlb_remove_ptdesc((tlb), page_ptdesc(pte))
 
 #ifndef __PAGETABLE_PMD_FOLDED
diff --git a/include/asm-generic/pgalloc.h b/include/asm-generic/pgalloc.h
index 051aa1331051..a1de7d246754 100644
--- a/include/asm-generic/pgalloc.h
+++ b/include/asm-generic/pgalloc.h
@@ -19,6 +19,7 @@
 static inline pte_t *__pte_alloc_one_kernel_noprof(struct mm_struct *mm)
 {
 	struct ptdesc *ptdesc = pagetable_alloc_noprof(GFP_PGTABLE_KERNEL, 0);
+	pte_t *pte;
 
 	if (!ptdesc)
 		return NULL;
@@ -29,7 +30,10 @@ static inline pte_t *__pte_alloc_one_kernel_noprof(struct mm_struct *mm)
 
 	ptdesc_set_kernel(ptdesc);
 
-	return ptdesc_address(ptdesc);
+	pte = ptdesc_address(ptdesc);
+	kernel_pte_init(pte);
+
+	return pte;
 }
 #define __pte_alloc_one_kernel(...)	alloc_hooks(__pte_alloc_one_kernel_noprof(__VA_ARGS__))
 
-- 
2.54.0