arm64/mm: define ptdesc_t

Define ptdesc_t type which describes the basic page table descriptor
layout on arm64 platform.  Subsequently all level specific pxxval_t
descriptors are derived from ptdesc_t thus establishing a common original
format, which can also be appropriate for page table entries, masks and
protection values etc which are used at all page table levels.

Link: https://lkml.kernel.org/r/20250407053113.746295-4-anshuman.khandual@arm.com
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Suggested-by: Ryan Roberts <ryan.roberts@arm.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Ard Biesheuvel <ardb@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Gerald Schaefer <gerald.schaefer@linux.ibm.com>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Madhavan Srinivasan <maddy@linux.ibm.com>
Cc: Nicholas Piggin <npiggin@gmail.com>
Cc: Palmer Dabbelt <palmer@dabbelt.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/arch/arm64/include/asm/pgtable-types.h b/arch/arm64/include/asm/pgtable-types.h
index 6d6d4065b0cb4ed17ac8bba16495924c01d2e950..265e8301d7ba8f7db8370db6988682414537bbd7 100644 (file)
--- a/arch/arm64/include/asm/pgtable-types.h
+++ b/arch/arm64/include/asm/pgtable-types.h
@@ -11,11 +11,19 @@
 
 #include <asm/types.h>
 
-typedef u64 pteval_t;
-typedef u64 pmdval_t;
-typedef u64 pudval_t;
-typedef u64 p4dval_t;
-typedef u64 pgdval_t;
+/*
+ * Page Table Descriptor
+ *
+ * Generic page table descriptor format from which
+ * all level specific descriptors can be derived.
+ */
+typedef u64 ptdesc_t;
+
+typedef ptdesc_t pteval_t;
+typedef ptdesc_t pmdval_t;
+typedef ptdesc_t pudval_t;
+typedef ptdesc_t p4dval_t;
+typedef ptdesc_t pgdval_t;
 
 /*
  * These are used to make use of C type-checking..
@@ -46,7 +54,7 @@ typedef struct { pgdval_t pgd; } pgd_t;
 #define pgd_val(x)     ((x).pgd)
 #define __pgd(x)       ((pgd_t) { (x) } )
 
-typedef struct { pteval_t pgprot; } pgprot_t;
+typedef struct { ptdesc_t pgprot; } pgprot_t;
 #define pgprot_val(x)  ((x).pgprot)
 #define __pgprot(x)    ((pgprot_t) { (x) } )
 

diff --git a/arch/arm64/include/asm/ptdump.h b/arch/arm64/include/asm/ptdump.h
index 01033c1d38dc210de3ee31786afa84f880387a01..fded5358641f8f48c65142feff275fea8af3898b 100644 (file)
--- a/arch/arm64/include/asm/ptdump.h
+++ b/arch/arm64/include/asm/ptdump.h
@@ -24,8 +24,8 @@ struct ptdump_info {
 };
 
 struct ptdump_prot_bits {
-       u64             mask;
-       u64             val;
+       ptdesc_t        mask;
+       ptdesc_t        val;
        const char      *set;
        const char      *clear;
 };
@@ -34,7 +34,7 @@ struct ptdump_pg_level {
        const struct ptdump_prot_bits *bits;
        char name[4];
        int num;
-       u64 mask;
+       ptdesc_t mask;
 };
 
 /*
@@ -51,7 +51,7 @@ struct ptdump_pg_state {
        const struct mm_struct *mm;
        unsigned long start_address;
        int level;
-       u64 current_prot;
+       ptdesc_t current_prot;
        bool check_wx;
        unsigned long wx_pages;
        unsigned long uxn_pages;

diff --git a/arch/arm64/kernel/efi.c b/arch/arm64/kernel/efi.c
index 1d25d8899dbf7f32b54737fd04c303f09793cd0b..42e281c07c2f1a3a6d871c6e371a5a4c55e04777 100644 (file)
--- a/arch/arm64/kernel/efi.c
+++ b/arch/arm64/kernel/efi.c
@@ -29,7 +29,7 @@ static bool region_is_misaligned(const efi_memory_desc_t *md)
  * executable, everything else can be mapped with the XN bits
  * set. Also take the new (optional) RO/XP bits into account.
  */
-static __init pteval_t create_mapping_protection(efi_memory_desc_t *md)
+static __init ptdesc_t create_mapping_protection(efi_memory_desc_t *md)
 {
        u64 attr = md->attribute;
        u32 type = md->type;
@@ -83,7 +83,7 @@ static __init pteval_t create_mapping_protection(efi_memory_desc_t *md)
 
 int __init efi_create_mapping(struct mm_struct *mm, efi_memory_desc_t *md)
 {
-       pteval_t prot_val = create_mapping_protection(md);
+       ptdesc_t prot_val = create_mapping_protection(md);
        bool page_mappings_only = (md->type == EFI_RUNTIME_SERVICES_CODE ||
                                   md->type == EFI_RUNTIME_SERVICES_DATA);
 

diff --git a/arch/arm64/kernel/pi/map_kernel.c b/arch/arm64/kernel/pi/map_kernel.c
index c6650cfe706c34e8c4f5c178420b406e12b839c6..0f4bd77718590c970710f132aaca42f3790f01ef 100644 (file)
--- a/arch/arm64/kernel/pi/map_kernel.c
+++ b/arch/arm64/kernel/pi/map_kernel.c
@@ -159,7 +159,7 @@ static void noinline __section(".idmap.text") set_ttbr0_for_lpa2(u64 ttbr)
 static void __init remap_idmap_for_lpa2(void)
 {
        /* clear the bits that change meaning once LPA2 is turned on */
-       pteval_t mask = PTE_SHARED;
+       ptdesc_t mask = PTE_SHARED;
 
        /*
         * We have to clear bits [9:8] in all block or page descriptors in the

diff --git a/arch/arm64/kernel/pi/map_range.c b/arch/arm64/kernel/pi/map_range.c
index 81345f68f9fc04ef2a7549acdc4f1e181a4bdcc0..7982788e7b9aaa78fe199b832d3b65d2c31cfead 100644 (file)
--- a/arch/arm64/kernel/pi/map_range.c
+++ b/arch/arm64/kernel/pi/map_range.c
@@ -30,7 +30,7 @@ void __init map_range(u64 *pte, u64 start, u64 end, u64 pa, pgprot_t prot,
                      int level, pte_t *tbl, bool may_use_cont, u64 va_offset)
 {
        u64 cmask = (level == 3) ? CONT_PTE_SIZE - 1 : U64_MAX;
-       pteval_t protval = pgprot_val(prot) & ~PTE_TYPE_MASK;
+       ptdesc_t protval = pgprot_val(prot) & ~PTE_TYPE_MASK;
        int lshift = (3 - level) * PTDESC_TABLE_SHIFT;
        u64 lmask = (PAGE_SIZE << lshift) - 1;
 
@@ -87,7 +87,7 @@ void __init map_range(u64 *pte, u64 start, u64 end, u64 pa, pgprot_t prot,
        }
 }
 
-asmlinkage u64 __init create_init_idmap(pgd_t *pg_dir, pteval_t clrmask)
+asmlinkage u64 __init create_init_idmap(pgd_t *pg_dir, ptdesc_t clrmask)
 {
        u64 ptep = (u64)pg_dir + PAGE_SIZE;
        pgprot_t text_prot = PAGE_KERNEL_ROX;

diff --git a/arch/arm64/kernel/pi/pi.h b/arch/arm64/kernel/pi/pi.h
index c91e5e965cd39a1a353712353cee5e8ec09c8426..91dcb5b6bbd1f2c4b989a9a79bc80b1e4060a0e9 100644 (file)
--- a/arch/arm64/kernel/pi/pi.h
+++ b/arch/arm64/kernel/pi/pi.h
@@ -33,4 +33,4 @@ void map_range(u64 *pgd, u64 start, u64 end, u64 pa, pgprot_t prot,
 
 asmlinkage void early_map_kernel(u64 boot_status, void *fdt);
 
-asmlinkage u64 create_init_idmap(pgd_t *pgd, pteval_t clrmask);
+asmlinkage u64 create_init_idmap(pgd_t *pgd, ptdesc_t clrmask);

diff --git a/arch/arm64/mm/mmap.c b/arch/arm64/mm/mmap.c
index 07aeab8a760652efa3dcaeb154ea73c6a2185069..c86c348857c405ee138970511649e161b3ec2fca 100644 (file)
--- a/arch/arm64/mm/mmap.c
+++ b/arch/arm64/mm/mmap.c
@@ -83,7 +83,7 @@ arch_initcall(adjust_protection_map);
 
 pgprot_t vm_get_page_prot(unsigned long vm_flags)
 {
-       pteval_t prot;
+       ptdesc_t prot;
 
        /* Short circuit GCS to avoid bloating the table. */
        if (system_supports_gcs() && (vm_flags & VM_SHADOW_STACK)) {

diff --git a/arch/arm64/mm/ptdump.c b/arch/arm64/mm/ptdump.c
index ac0c20ba0cd9d3693ea00f28248509d84d5bfa63..421a5de806c62d5850dcba5d7030adf0b24dc7b9 100644 (file)
--- a/arch/arm64/mm/ptdump.c
+++ b/arch/arm64/mm/ptdump.c
@@ -194,7 +194,7 @@ void note_page(struct ptdump_state *pt_st, unsigned long addr, int level,
        struct ptdump_pg_state *st = container_of(pt_st, struct ptdump_pg_state, ptdump);
        struct ptdump_pg_level *pg_level = st->pg_level;
        static const char units[] = "KMGTPE";
-       u64 prot = 0;
+       ptdesc_t prot = 0;
 
        /* check if the current level has been folded dynamically */
        if (st->mm && ((level == 1 && mm_p4d_folded(st->mm)) ||