[PATCH v3 05/13] arm64: mm: Drop redundant pgd_t* argument from map_mem()

Ard Biesheuvel
2026-03-20T15:00:05Z

__map_memblock() and map_mem() always operate on swapper_pg_dir, so
there is no need to pass around a pgd_t pointer between them.

Reviewed-by: Ryan Roberts <ryan.roberts@arm.com>
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
---
arch/arm64/mm/mmu.c | 25 ++++++++++----------
1 file changed, 12 insertions(+), 13 deletions(-)

diff --git a/arch/arm64/mm/mmu.c b/arch/arm64/mm/mmu.c
index 652fe2c52b5a..744cf76f25aa 100644
--- a/arch/arm64/mm/mmu.c
+++ b/arch/arm64/mm/mmu.c
@@ -1019,11 +1019,11 @@ static void update_mapping_prot(phys_addr_t phys, unsigned long virt,
flush_tlb_kernel_range(virt, virt + size);
}

-static void __init __map_memblock(pgd_t *pgdp, phys_addr_t start,
- phys_addr_t end, pgprot_t prot, int flags)
+static void __init __map_memblock(phys_addr_t start, phys_addr_t end,
+ pgprot_t prot, int flags)
{
- early_create_pgd_mapping(pgdp, start, __phys_to_virt(start), end - start,
- prot, early_pgtable_alloc, flags);
+ early_create_pgd_mapping(swapper_pg_dir, start, __phys_to_virt(start),
+ end - start, prot, early_pgtable_alloc, flags);
}

void __init mark_linear_text_alias_ro(void)
@@ -1071,13 +1071,13 @@ static phys_addr_t __init arm64_kfence_alloc_pool(void)
return kfence_pool;
}

-static void __init arm64_kfence_map_pool(phys_addr_t kfence_pool, pgd_t *pgdp)
+static void __init arm64_kfence_map_pool(phys_addr_t kfence_pool)
{
if (!kfence_pool)
return;

/* KFENCE pool needs page-level mapping. */
- __map_memblock(pgdp, kfence_pool, kfence_pool + KFENCE_POOL_SIZE,
+ __map_memblock(kfence_pool, kfence_pool + KFENCE_POOL_SIZE,
pgprot_tagged(PAGE_KERNEL),
NO_BLOCK_MAPPINGS | NO_CONT_MAPPINGS);
memblock_clear_nomap(kfence_pool, KFENCE_POOL_SIZE);
@@ -1113,11 +1113,11 @@ bool arch_kfence_init_pool(void)
#else /* CONFIG_KFENCE */

static inline phys_addr_t arm64_kfence_alloc_pool(void) { return 0; }
-static inline void arm64_kfence_map_pool(phys_addr_t kfence_pool, pgd_t *pgdp) { }
+static inline void arm64_kfence_map_pool(phys_addr_t kfence_pool) { }

#endif /* CONFIG_KFENCE */

-static void __init map_mem(pgd_t *pgdp)
+static void __init map_mem(void)
{
static const u64 direct_map_end = _PAGE_END(VA_BITS_MIN);
phys_addr_t kernel_start = __pa_symbol(_text);
@@ -1162,7 +1162,7 @@ static void __init map_mem(pgd_t *pgdp)
* if MTE is present. Otherwise, it has the same attributes as
* PAGE_KERNEL.
*/
- __map_memblock(pgdp, start, end, pgprot_tagged(PAGE_KERNEL),
+ __map_memblock(start, end, pgprot_tagged(PAGE_KERNEL),
flags);
}

@@ -1176,10 +1176,9 @@ static void __init map_mem(pgd_t *pgdp)
* Note that contiguous mappings cannot be remapped in this way,
* so we should avoid them here.
*/
- __map_memblock(pgdp, kernel_start, kernel_end,
- PAGE_KERNEL, NO_CONT_MAPPINGS);
+ __map_memblock(kernel_start, kernel_end, PAGE_KERNEL, NO_CONT_MAPPINGS);
memblock_clear_nomap(kernel_start, kernel_end - kernel_start);
- arm64_kfence_map_pool(early_kfence_pool, pgdp);
+ arm64_kfence_map_pool(early_kfence_pool);
}

void mark_rodata_ro(void)
@@ -1401,7 +1400,7 @@ static void __init create_idmap(void)

void __init paging_init(void)
{
- map_mem(swapper_pg_dir);
+ map_mem();

memblock_allow_resize();

--
2.53.0.959.g497ff81fa9-goog