From patchwork series 487918

https://patchwork.ozlabs.org//project/linuxppc-dev/list/?series=487918

Author: Fox Snowpatch

Documentation/driver-api/cxl/linux/early-boot.rst

@@ -125,7 +125,7 @@ The contiguous memory allocator (CMA) enables reservation of contiguous memory
 regions on NUMA nodes during early boot.  However, CMA cannot reserve memory
 on NUMA nodes that are not online during early boot. ::
 
-  void __init hugetlb_cma_reserve(int order) {
+  void __init hugetlb_cma_reserve(void) {
     if (!node_online(nid))
       /* do not allow reservations */
   }

Documentation/mm/memory-model.rst

@@ -97,9 +97,6 @@ sections:
   `mem_section` objects and the number of rows is calculated to fit
   all the memory sections.
 
-The architecture setup code should call sparse_init() to
-initialize the memory sections and the memory maps.
-
 With SPARSEMEM there are two possible ways to convert a PFN to the
 corresponding `struct page` - a "classic sparse" and "sparse
 vmemmap". The selection is made at build time and it is determined by

Documentation/translations/zh_CN/mm/memory-model.rst

@@ -83,8 +83,6 @@ SPARSEMEM模型将物理内存显示为一个部分的集合。一个区段用me
   每一行包含价值 `PAGE_SIZE` 的 `mem_section` 对象，行数的计算是为了适应所有的
   内存区。
 
-架构设置代码应该调用sparse_init()来初始化内存区和内存映射。
-
 通过SPARSEMEM，有两种可能的方式将PFN转换为相应的 `struct page` --"classic sparse"和
  "sparse vmemmap"。选择是在构建时进行的，它由 `CONFIG_SPARSEMEM_VMEMMAP` 的
  值决定。

arch/alpha/kernel/setup.c

@@ -607,7 +607,6 @@ setup_arch(char **cmdline_p)
 	/* Find our memory.  */
 	setup_memory(kernel_end);
 	memblock_set_bottom_up(true);
-	sparse_init();
 
 	/* First guess at cpu cache sizes.  Do this before init_arch.  */
 	determine_cpu_caches(cpu->type);

arch/alpha/mm/init.c

@@ -208,24 +208,22 @@ callback_init(void * kernel_end)
 	return kernel_end;
 }
 
-/*
- * paging_init() sets up the memory map.
- */
-void __init paging_init(void)
+void __init arch_zone_limits_init(unsigned long *max_zone_pfn)
 {
-	unsigned long max_zone_pfn[MAX_NR_ZONES] = {0, };
 	unsigned long dma_pfn;
 
 	dma_pfn = virt_to_phys((char *)MAX_DMA_ADDRESS) >> PAGE_SHIFT;
 	max_pfn = max_low_pfn;
 
 	max_zone_pfn[ZONE_DMA] = dma_pfn;
 	max_zone_pfn[ZONE_NORMAL] = max_pfn;
+}
 
-	/* Initialize mem_map[].  */
-	free_area_init(max_zone_pfn);
-
-	/* Initialize the kernel's ZERO_PGE. */
+/*
+ * paging_init() initializes the kernel's ZERO_PGE.
+ */
+void __init paging_init(void)
+{
 	memset(absolute_pointer(ZERO_PGE), 0, PAGE_SIZE);
 }
 

arch/arc/mm/init.c

@@ -75,6 +75,25 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
 		base, TO_MB(size), !in_use ? "Not used":"");
 }
 
+void __init arch_zone_limits_init(unsigned long *max_zone_pfn)
+{
+	/*----------------- node/zones setup --------------------------*/
+	max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
+
+#ifdef CONFIG_HIGHMEM
+	/*
+	 * max_high_pfn should be ok here for both HIGHMEM and HIGHMEM+PAE.
+	 * For HIGHMEM without PAE max_high_pfn should be less than
+	 * min_low_pfn to guarantee that these two regions don't overlap.
+	 * For PAE case highmem is greater than lowmem, so it is natural
+	 * to use max_high_pfn.
+	 *
+	 * In both cases, holes should be handled by pfn_valid().
+	 */
+	max_zone_pfn[ZONE_HIGHMEM] = max_high_pfn;
+#endif
+}
+
 /*
  * First memory setup routine called from setup_arch()
  * 1. setup swapper's mm @init_mm
@@ -83,8 +102,6 @@ void __init early_init_dt_add_memory_arch(u64 base, u64 size)
  */
 void __init setup_arch_memory(void)
 {
-	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
-
 	setup_initial_init_mm(_text, _etext, _edata, _end);
 
 	/* first page of system - kernel .vector starts here */
@@ -122,9 +139,6 @@ void __init setup_arch_memory(void)
 
 	memblock_dump_all();
 
-	/*----------------- node/zones setup --------------------------*/
-	max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
-
 #ifdef CONFIG_HIGHMEM
 	/*
 	 * On ARC (w/o PAE) HIGHMEM addresses are actually smaller (0 based)
@@ -139,22 +153,9 @@ void __init setup_arch_memory(void)
 	min_high_pfn = PFN_DOWN(high_mem_start);
 	max_high_pfn = PFN_DOWN(high_mem_start + high_mem_sz);
 
-	/*
-	 * max_high_pfn should be ok here for both HIGHMEM and HIGHMEM+PAE.
-	 * For HIGHMEM without PAE max_high_pfn should be less than
-	 * min_low_pfn to guarantee that these two regions don't overlap.
-	 * For PAE case highmem is greater than lowmem, so it is natural
-	 * to use max_high_pfn.
-	 *
-	 * In both cases, holes should be handled by pfn_valid().
-	 */
-	max_zone_pfn[ZONE_HIGHMEM] = max_high_pfn;
-
 	arch_pfn_offset = min(min_low_pfn, min_high_pfn);
 	kmap_init();
 #endif /* CONFIG_HIGHMEM */
-
-	free_area_init(max_zone_pfn);
 }
 
 void __init arch_mm_preinit(void)

arch/arm/include/asm/pgtable.h

@@ -15,8 +15,8 @@
  * ZERO_PAGE is a global shared page that is always zero: used
  * for zero-mapped memory areas etc..
  */
-extern struct page *empty_zero_page;
-#define ZERO_PAGE(vaddr)	(empty_zero_page)
+extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
+#define ZERO_PAGE(vaddr)	(virt_to_page(empty_zero_page))
 #endif
 
 #include <asm-generic/pgtable-nopud.h>

arch/arm/mm/init.c

@@ -107,19 +107,15 @@ void __init setup_dma_zone(const struct machine_desc *mdesc)
 #endif
 }
 
-static void __init zone_sizes_init(unsigned long min, unsigned long max_low,
-	unsigned long max_high)
+void __init arch_zone_limits_init(unsigned long *max_zone_pfn)
 {
-	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0 };
-
 #ifdef CONFIG_ZONE_DMA
-	max_zone_pfn[ZONE_DMA] = min(arm_dma_pfn_limit, max_low);
+	max_zone_pfn[ZONE_DMA] = min(arm_dma_pfn_limit, max_low_pfn);
 #endif
-	max_zone_pfn[ZONE_NORMAL] = max_low;
+	max_zone_pfn[ZONE_NORMAL] = max_low_pfn;
 #ifdef CONFIG_HIGHMEM
-	max_zone_pfn[ZONE_HIGHMEM] = max_high;
+	max_zone_pfn[ZONE_HIGHMEM] = max_pfn;
 #endif
-	free_area_init(max_zone_pfn);
 }
 
 #ifdef CONFIG_HAVE_ARCH_PFN_VALID
@@ -211,19 +207,6 @@ void __init bootmem_init(void)
 
 	early_memtest((phys_addr_t)min_low_pfn << PAGE_SHIFT,
 		      (phys_addr_t)max_low_pfn << PAGE_SHIFT);
-
-	/*
-	 * sparse_init() tries to allocate memory from memblock, so must be
-	 * done after the fixed reservations
-	 */
-	sparse_init();
-
-	/*
-	 * Now free the memory - free_area_init needs
-	 * the sparse mem_map arrays initialized by sparse_init()
-	 * for memmap_init_zone(), otherwise all PFNs are invalid.
-	 */
-	zone_sizes_init(min_low_pfn, max_low_pfn, max_pfn);
 }
 
 /*

arch/arm/mm/mmu.c

@@ -45,7 +45,7 @@ extern unsigned long __atags_pointer;
  * empty_zero_page is a special page that is used for
  * zero-initialized data and COW.
  */
-struct page *empty_zero_page;
+unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
 EXPORT_SYMBOL(empty_zero_page);
 
 /*
@@ -1754,8 +1754,6 @@ static void __init early_fixmap_shutdown(void)
  */
 void __init paging_init(const struct machine_desc *mdesc)
 {
-	void *zero_page;
-
 #ifdef CONFIG_XIP_KERNEL
 	/* Store the kernel RW RAM region start/end in these variables */
 	kernel_sec_start = CONFIG_PHYS_OFFSET & SECTION_MASK;
@@ -1781,13 +1779,7 @@ void __init paging_init(const struct machine_desc *mdesc)
 
 	top_pmd = pmd_off_k(0xffff0000);
 
-	/* allocate the zero page. */
-	zero_page = early_alloc(PAGE_SIZE);
-
 	bootmem_init();
-
-	empty_zero_page = virt_to_page(zero_page);
-	__flush_dcache_folio(NULL, page_folio(empty_zero_page));
 }
 
 void __init early_mm_init(const struct machine_desc *mdesc)

arch/arm/mm/nommu.c

@@ -31,7 +31,7 @@ unsigned long vectors_base;
  * empty_zero_page is a special page that is used for
  * zero-initialized data and COW.
  */
-struct page *empty_zero_page;
+unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)] __page_aligned_bss;
 EXPORT_SYMBOL(empty_zero_page);
 
 #ifdef CONFIG_ARM_MPU
@@ -156,18 +156,10 @@ void __init adjust_lowmem_bounds(void)
  */
 void __init paging_init(const struct machine_desc *mdesc)
 {
-	void *zero_page;
-
 	early_trap_init((void *)vectors_base);
 	mpu_setup();
 
-	/* allocate the zero page. */
-	zero_page = (void *)memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
-
 	bootmem_init();
-
-	empty_zero_page = virt_to_page(zero_page);
-	flush_dcache_page(empty_zero_page);
 }
 
 /*