[PATCH v2] arm64: mm: Use generic enum pgtable_level
From: Kevin Brodsky
Date: Wed Mar 18 2026 - 05:38:20 EST
enum pgtable_type was introduced for arm64 by commit c64f46ee1377
("arm64: mm: use enum to identify pgtable level instead of
*_SHIFT"). In the meantime, the generic enum pgtable_level got
introduced by commit b22cc9a9c7ff ("mm/rmap: convert "enum
rmap_level" to "enum pgtable_level"").
Let's switch to the generic enum pgtable_level. The only difference
is that it also includes PGD level; __pgd_pgtable_alloc() isn't
expected to create PGD tables so we add a VM_WARN_ON() for that
case.
Suggested-by: David Hildenbrand (Arm) <david@xxxxxxxxxx>
Reviewed-by: David Hildenbrand (Arm) <david@xxxxxxxxxx>
Reviewed-by: Ryan Roberts <ryan.roberts@xxxxxxx>
Signed-off-by: Kevin Brodsky <kevin.brodsky@xxxxxxx>
---
v1..v2:
- Add a VM_WARN_ON() for PGD in __pgd_pgtable_alloc() [Ryan, David]
Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
---
arch/arm64/include/asm/mmu.h | 7 -----
arch/arm64/mm/mmu.c | 59 +++++++++++++++++++-----------------
2 files changed, 31 insertions(+), 35 deletions(-)
diff --git a/arch/arm64/include/asm/mmu.h b/arch/arm64/include/asm/mmu.h
index 137a173df1ff..f28e6e215da4 100644
--- a/arch/arm64/include/asm/mmu.h
+++ b/arch/arm64/include/asm/mmu.h
@@ -17,13 +17,6 @@
#include <linux/refcount.h>
#include <asm/cpufeature.h>
-enum pgtable_type {
- TABLE_PTE,
- TABLE_PMD,
- TABLE_PUD,
- TABLE_P4D,
-};
-
typedef struct {
atomic64_t id;
#ifdef CONFIG_COMPAT
diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index a6a00accf4f9..c45a6a47dad0 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -112,7 +112,7 @@ pgprot_t phys_mem_access_prot(struct file *file, unsigned long pfn,
}
EXPORT_SYMBOL(phys_mem_access_prot);
-static phys_addr_t __init early_pgtable_alloc(enum pgtable_type pgtable_type)
+static phys_addr_t __init early_pgtable_alloc(enum pgtable_level pgtable_level)
{
phys_addr_t phys;
@@ -197,7 +197,7 @@ static void init_pte(pte_t *ptep, unsigned long addr, unsigned long end,
static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr,
unsigned long end, phys_addr_t phys,
pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(enum pgtable_type),
+ phys_addr_t (*pgtable_alloc)(enum pgtable_level),
int flags)
{
unsigned long next;
@@ -212,7 +212,7 @@ static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr,
if (flags & NO_EXEC_MAPPINGS)
pmdval |= PMD_TABLE_PXN;
BUG_ON(!pgtable_alloc);
- pte_phys = pgtable_alloc(TABLE_PTE);
+ pte_phys = pgtable_alloc(PGTABLE_LEVEL_PTE);
if (pte_phys == INVALID_PHYS_ADDR)
return -ENOMEM;
ptep = pte_set_fixmap(pte_phys);
@@ -252,7 +252,7 @@ static int alloc_init_cont_pte(pmd_t *pmdp, unsigned long addr,
static int init_pmd(pmd_t *pmdp, unsigned long addr, unsigned long end,
phys_addr_t phys, pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(enum pgtable_type), int flags)
+ phys_addr_t (*pgtable_alloc)(enum pgtable_level), int flags)
{
unsigned long next;
@@ -292,7 +292,7 @@ static int init_pmd(pmd_t *pmdp, unsigned long addr, unsigned long end,
static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr,
unsigned long end, phys_addr_t phys,
pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(enum pgtable_type),
+ phys_addr_t (*pgtable_alloc)(enum pgtable_level),
int flags)
{
int ret;
@@ -311,7 +311,7 @@ static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr,
if (flags & NO_EXEC_MAPPINGS)
pudval |= PUD_TABLE_PXN;
BUG_ON(!pgtable_alloc);
- pmd_phys = pgtable_alloc(TABLE_PMD);
+ pmd_phys = pgtable_alloc(PGTABLE_LEVEL_PMD);
if (pmd_phys == INVALID_PHYS_ADDR)
return -ENOMEM;
pmdp = pmd_set_fixmap(pmd_phys);
@@ -349,7 +349,7 @@ static int alloc_init_cont_pmd(pud_t *pudp, unsigned long addr,
static int alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end,
phys_addr_t phys, pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(enum pgtable_type),
+ phys_addr_t (*pgtable_alloc)(enum pgtable_level),
int flags)
{
int ret = 0;
@@ -364,7 +364,7 @@ static int alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end,
if (flags & NO_EXEC_MAPPINGS)
p4dval |= P4D_TABLE_PXN;
BUG_ON(!pgtable_alloc);
- pud_phys = pgtable_alloc(TABLE_PUD);
+ pud_phys = pgtable_alloc(PGTABLE_LEVEL_PUD);
if (pud_phys == INVALID_PHYS_ADDR)
return -ENOMEM;
pudp = pud_set_fixmap(pud_phys);
@@ -415,7 +415,7 @@ static int alloc_init_pud(p4d_t *p4dp, unsigned long addr, unsigned long end,
static int alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end,
phys_addr_t phys, pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(enum pgtable_type),
+ phys_addr_t (*pgtable_alloc)(enum pgtable_level),
int flags)
{
int ret;
@@ -430,7 +430,7 @@ static int alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end,
if (flags & NO_EXEC_MAPPINGS)
pgdval |= PGD_TABLE_PXN;
BUG_ON(!pgtable_alloc);
- p4d_phys = pgtable_alloc(TABLE_P4D);
+ p4d_phys = pgtable_alloc(PGTABLE_LEVEL_P4D);
if (p4d_phys == INVALID_PHYS_ADDR)
return -ENOMEM;
p4dp = p4d_set_fixmap(p4d_phys);
@@ -467,7 +467,7 @@ static int alloc_init_p4d(pgd_t *pgdp, unsigned long addr, unsigned long end,
static int __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys,
unsigned long virt, phys_addr_t size,
pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(enum pgtable_type),
+ phys_addr_t (*pgtable_alloc)(enum pgtable_level),
int flags)
{
int ret;
@@ -500,7 +500,7 @@ static int __create_pgd_mapping_locked(pgd_t *pgdir, phys_addr_t phys,
static int __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys,
unsigned long virt, phys_addr_t size,
pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(enum pgtable_type),
+ phys_addr_t (*pgtable_alloc)(enum pgtable_level),
int flags)
{
int ret;
@@ -516,7 +516,7 @@ static int __create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys,
static void early_create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys,
unsigned long virt, phys_addr_t size,
pgprot_t prot,
- phys_addr_t (*pgtable_alloc)(enum pgtable_type),
+ phys_addr_t (*pgtable_alloc)(enum pgtable_level),
int flags)
{
int ret;
@@ -528,7 +528,7 @@ static void early_create_pgd_mapping(pgd_t *pgdir, phys_addr_t phys,
}
static phys_addr_t __pgd_pgtable_alloc(struct mm_struct *mm, gfp_t gfp,
- enum pgtable_type pgtable_type)
+ enum pgtable_level pgtable_level)
{
/* Page is zeroed by init_clear_pgtable() so don't duplicate effort. */
struct ptdesc *ptdesc = pagetable_alloc(gfp & ~__GFP_ZERO, 0);
@@ -539,40 +539,43 @@ static phys_addr_t __pgd_pgtable_alloc(struct mm_struct *mm, gfp_t gfp,
pa = page_to_phys(ptdesc_page(ptdesc));
- switch (pgtable_type) {
- case TABLE_PTE:
+ switch (pgtable_level) {
+ case PGTABLE_LEVEL_PTE:
BUG_ON(!pagetable_pte_ctor(mm, ptdesc));
break;
- case TABLE_PMD:
+ case PGTABLE_LEVEL_PMD:
BUG_ON(!pagetable_pmd_ctor(mm, ptdesc));
break;
- case TABLE_PUD:
+ case PGTABLE_LEVEL_PUD:
pagetable_pud_ctor(ptdesc);
break;
- case TABLE_P4D:
+ case PGTABLE_LEVEL_P4D:
pagetable_p4d_ctor(ptdesc);
break;
+ case PGTABLE_LEVEL_PGD:
+ VM_WARN_ON(1);
+ break;
}
return pa;
}
static phys_addr_t
-pgd_pgtable_alloc_init_mm_gfp(enum pgtable_type pgtable_type, gfp_t gfp)
+pgd_pgtable_alloc_init_mm_gfp(enum pgtable_level pgtable_level, gfp_t gfp)
{
- return __pgd_pgtable_alloc(&init_mm, gfp, pgtable_type);
+ return __pgd_pgtable_alloc(&init_mm, gfp, pgtable_level);
}
static phys_addr_t __maybe_unused
-pgd_pgtable_alloc_init_mm(enum pgtable_type pgtable_type)
+pgd_pgtable_alloc_init_mm(enum pgtable_level pgtable_level)
{
- return pgd_pgtable_alloc_init_mm_gfp(pgtable_type, GFP_PGTABLE_KERNEL);
+ return pgd_pgtable_alloc_init_mm_gfp(pgtable_level, GFP_PGTABLE_KERNEL);
}
static phys_addr_t
-pgd_pgtable_alloc_special_mm(enum pgtable_type pgtable_type)
+pgd_pgtable_alloc_special_mm(enum pgtable_level pgtable_level)
{
- return __pgd_pgtable_alloc(NULL, GFP_PGTABLE_KERNEL, pgtable_type);
+ return __pgd_pgtable_alloc(NULL, GFP_PGTABLE_KERNEL, pgtable_level);
}
static void split_contpte(pte_t *ptep)
@@ -593,7 +596,7 @@ static int split_pmd(pmd_t *pmdp, pmd_t pmd, gfp_t gfp, bool to_cont)
pte_t *ptep;
int i;
- pte_phys = pgd_pgtable_alloc_init_mm_gfp(TABLE_PTE, gfp);
+ pte_phys = pgd_pgtable_alloc_init_mm_gfp(PGTABLE_LEVEL_PTE, gfp);
if (pte_phys == INVALID_PHYS_ADDR)
return -ENOMEM;
ptep = (pte_t *)phys_to_virt(pte_phys);
@@ -638,7 +641,7 @@ static int split_pud(pud_t *pudp, pud_t pud, gfp_t gfp, bool to_cont)
pmd_t *pmdp;
int i;
- pmd_phys = pgd_pgtable_alloc_init_mm_gfp(TABLE_PMD, gfp);
+ pmd_phys = pgd_pgtable_alloc_init_mm_gfp(PGTABLE_LEVEL_PMD, gfp);
if (pmd_phys == INVALID_PHYS_ADDR)
return -ENOMEM;
pmdp = (pmd_t *)phys_to_virt(pmd_phys);
@@ -1226,7 +1229,7 @@ static void __init declare_vma(struct vm_struct *vma,
static phys_addr_t kpti_ng_temp_alloc __initdata;
-static phys_addr_t __init kpti_ng_pgd_alloc(enum pgtable_type type)
+static phys_addr_t __init kpti_ng_pgd_alloc(enum pgtable_level pgtable_level)
{
kpti_ng_temp_alloc -= PAGE_SIZE;
return kpti_ng_temp_alloc;
--
2.51.2