riscv: mm: Change attribute from __init to __meminit for page functions

Prepare for memory hotplugging support by changing from __init to
__meminit for the page table functions that are used by the upcoming
architecture specific callbacks.

Changing the __init attribute to __meminit, avoids that the functions
are removed after init. The __meminit attribute makes sure the
functions are kept in the kernel text post init, but only if memory
hotplugging is enabled for the build.
Reviewed-by: Alexandre Ghiti <alexghiti@rivosinc.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Signed-off-by: Björn Töpel <bjorn@rivosinc.com>
Link: https://lore.kernel.org/r/20240605114100.315918-4-bjorn@kernel.orgSigned-off-by: Palmer Dabbelt <palmer@rivosinc.com>

arch/riscv/include/asm/mmu.h

@@ -31,8 +31,8 @@ typedef struct {
 #define cntx2asid(cntx)		((cntx) & SATP_ASID_MASK)
 #define cntx2version(cntx)	((cntx) & ~SATP_ASID_MASK)
 
-void __init create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa,
-			       phys_addr_t sz, pgprot_t prot);
+void __meminit create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
+				  pgprot_t prot);
 #endif /* __ASSEMBLY__ */
 
 #endif /* _ASM_RISCV_MMU_H */

arch/riscv/include/asm/pgtable.h

@@ -165,7 +165,7 @@ struct pt_alloc_ops {
 #endif
 };
 
-extern struct pt_alloc_ops pt_ops __initdata;
+extern struct pt_alloc_ops pt_ops __meminitdata;
 
 #ifdef CONFIG_MMU
 /* Number of PGD entries that a user-mode program can use */

arch/riscv/mm/init.c

@@ -296,7 +296,7 @@ static void __init setup_bootmem(void)
 }
 
 #ifdef CONFIG_MMU
-struct pt_alloc_ops pt_ops __initdata;
+struct pt_alloc_ops pt_ops __meminitdata;
 
 pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
 pgd_t trampoline_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
@@ -358,7 +358,7 @@ static inline pte_t *__init get_pte_virt_fixmap(phys_addr_t pa)
 	return (pte_t *)set_fixmap_offset(FIX_PTE, pa);
 }
 
-static inline pte_t *__init get_pte_virt_late(phys_addr_t pa)
+static inline pte_t *__meminit get_pte_virt_late(phys_addr_t pa)
 {
 	return (pte_t *) __va(pa);
 }
@@ -377,7 +377,7 @@ static inline phys_addr_t __init alloc_pte_fixmap(uintptr_t va)
 	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 }
 
-static phys_addr_t __init alloc_pte_late(uintptr_t va)
+static phys_addr_t __meminit alloc_pte_late(uintptr_t va)
 {
 	struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
 
@@ -385,9 +385,8 @@ static phys_addr_t __init alloc_pte_late(uintptr_t va)
 	return __pa((pte_t *)ptdesc_address(ptdesc));
 }
 
-static void __init create_pte_mapping(pte_t *ptep,
-				      uintptr_t va, phys_addr_t pa,
-				      phys_addr_t sz, pgprot_t prot)
+static void __meminit create_pte_mapping(pte_t *ptep, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
+					 pgprot_t prot)
 {
 	uintptr_t pte_idx = pte_index(va);
 
@@ -441,7 +440,7 @@ static pmd_t *__init get_pmd_virt_fixmap(phys_addr_t pa)
 	return (pmd_t *)set_fixmap_offset(FIX_PMD, pa);
 }
 
-static pmd_t *__init get_pmd_virt_late(phys_addr_t pa)
+static pmd_t *__meminit get_pmd_virt_late(phys_addr_t pa)
 {
 	return (pmd_t *) __va(pa);
 }
@@ -458,7 +457,7 @@ static phys_addr_t __init alloc_pmd_fixmap(uintptr_t va)
 	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 }
 
-static phys_addr_t __init alloc_pmd_late(uintptr_t va)
+static phys_addr_t __meminit alloc_pmd_late(uintptr_t va)
 {
 	struct ptdesc *ptdesc = pagetable_alloc(GFP_KERNEL & ~__GFP_HIGHMEM, 0);
 
@@ -466,9 +465,9 @@ static phys_addr_t __init alloc_pmd_late(uintptr_t va)
 	return __pa((pmd_t *)ptdesc_address(ptdesc));
 }
 
-static void __init create_pmd_mapping(pmd_t *pmdp,
-				      uintptr_t va, phys_addr_t pa,
-				      phys_addr_t sz, pgprot_t prot)
+static void __meminit create_pmd_mapping(pmd_t *pmdp,
+					 uintptr_t va, phys_addr_t pa,
+					 phys_addr_t sz, pgprot_t prot)
 {
 	pte_t *ptep;
 	phys_addr_t pte_phys;
@@ -504,7 +503,7 @@ static pud_t *__init get_pud_virt_fixmap(phys_addr_t pa)
 	return (pud_t *)set_fixmap_offset(FIX_PUD, pa);
 }
 
-static pud_t *__init get_pud_virt_late(phys_addr_t pa)
+static pud_t *__meminit get_pud_virt_late(phys_addr_t pa)
 {
 	return (pud_t *)__va(pa);
 }
@@ -522,7 +521,7 @@ static phys_addr_t __init alloc_pud_fixmap(uintptr_t va)
 	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 }
 
-static phys_addr_t alloc_pud_late(uintptr_t va)
+static phys_addr_t __meminit alloc_pud_late(uintptr_t va)
 {
 	unsigned long vaddr;
 
@@ -542,7 +541,7 @@ static p4d_t *__init get_p4d_virt_fixmap(phys_addr_t pa)
 	return (p4d_t *)set_fixmap_offset(FIX_P4D, pa);
 }
 
-static p4d_t *__init get_p4d_virt_late(phys_addr_t pa)
+static p4d_t *__meminit get_p4d_virt_late(phys_addr_t pa)
 {
 	return (p4d_t *)__va(pa);
 }
@@ -560,7 +559,7 @@ static phys_addr_t __init alloc_p4d_fixmap(uintptr_t va)
 	return memblock_phys_alloc(PAGE_SIZE, PAGE_SIZE);
 }
 
-static phys_addr_t alloc_p4d_late(uintptr_t va)
+static phys_addr_t __meminit alloc_p4d_late(uintptr_t va)
 {
 	unsigned long vaddr;
 
@@ -569,9 +568,8 @@ static phys_addr_t alloc_p4d_late(uintptr_t va)
 	return __pa(vaddr);
 }
 
-static void __init create_pud_mapping(pud_t *pudp,
-				      uintptr_t va, phys_addr_t pa,
-				      phys_addr_t sz, pgprot_t prot)
+static void __meminit create_pud_mapping(pud_t *pudp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
+					 pgprot_t prot)
 {
 	pmd_t *nextp;
 	phys_addr_t next_phys;
@@ -596,9 +594,8 @@ static void __init create_pud_mapping(pud_t *pudp,
 	create_pmd_mapping(nextp, va, pa, sz, prot);
 }
 
-static void __init create_p4d_mapping(p4d_t *p4dp,
-				      uintptr_t va, phys_addr_t pa,
-				      phys_addr_t sz, pgprot_t prot)
+static void __meminit create_p4d_mapping(p4d_t *p4dp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
+					 pgprot_t prot)
 {
 	pud_t *nextp;
 	phys_addr_t next_phys;
@@ -654,9 +651,8 @@ static void __init create_p4d_mapping(p4d_t *p4dp,
 #define create_pmd_mapping(__pmdp, __va, __pa, __sz, __prot) do {} while(0)
 #endif /* __PAGETABLE_PMD_FOLDED */
 
-void __init create_pgd_mapping(pgd_t *pgdp,
-				      uintptr_t va, phys_addr_t pa,
-				      phys_addr_t sz, pgprot_t prot)
+void __meminit create_pgd_mapping(pgd_t *pgdp, uintptr_t va, phys_addr_t pa, phys_addr_t sz,
+				  pgprot_t prot)
 {
 	pgd_next_t *nextp;
 	phys_addr_t next_phys;
@@ -681,8 +677,7 @@ void __init create_pgd_mapping(pgd_t *pgdp,
 	create_pgd_next_mapping(nextp, va, pa, sz, prot);
 }
 
-static uintptr_t __init best_map_size(phys_addr_t pa, uintptr_t va,
-				      phys_addr_t size)
+static uintptr_t __meminit best_map_size(phys_addr_t pa, uintptr_t va, phys_addr_t size)
 {
 	if (debug_pagealloc_enabled())
 		return PAGE_SIZE;
@@ -718,7 +713,7 @@ asmlinkage void __init __copy_data(void)
 #endif
 
 #ifdef CONFIG_STRICT_KERNEL_RWX
-static __init pgprot_t pgprot_from_va(uintptr_t va)
+static __meminit pgprot_t pgprot_from_va(uintptr_t va)
 {
 	if (is_va_kernel_text(va))
 		return PAGE_KERNEL_READ_EXEC;
@@ -743,7 +738,7 @@ void mark_rodata_ro(void)
 				  set_memory_ro);
 }
 #else
-static __init pgprot_t pgprot_from_va(uintptr_t va)
+static __meminit pgprot_t pgprot_from_va(uintptr_t va)
 {
 	if (IS_ENABLED(CONFIG_64BIT) && !is_kernel_mapping(va))
 		return PAGE_KERNEL;
@@ -1235,9 +1230,8 @@ asmlinkage void __init setup_vm(uintptr_t dtb_pa)
 	pt_ops_set_fixmap();
 }
 
-static void __init create_linear_mapping_range(phys_addr_t start,
-					       phys_addr_t end,
-					       uintptr_t fixed_map_size)
+static void __meminit create_linear_mapping_range(phys_addr_t start, phys_addr_t end,
+						  uintptr_t fixed_map_size)
 {
 	phys_addr_t pa;
 	uintptr_t va, map_size;