1 files changed, 299 insertions, 83 deletions

diff --git a/arch/m68k/mm/motorola.c b/arch/m68k/mm/motorola.c
index 251c5437787b..62283bc2ed79 100644
--- a/arch/m68k/mm/motorola.c
+++ b/arch/m68k/mm/motorola.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
 /*
  * linux/arch/m68k/mm/motorola.c
  *
@@ -17,16 +18,15 @@
 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/init.h>
-#include <linux/bootmem.h>
+#include <linux/memblock.h>
 #include <linux/gfp.h>
 
 #include <asm/setup.h>
-#include <asm/uaccess.h>
+#include <linux/uaccess.h>
 #include <asm/page.h>
 #include <asm/pgalloc.h>
 #include <asm/machdep.h>
 #include <asm/io.h>
-#include <asm/dma.h>
 #ifdef CONFIG_ATARI
 #include <asm/atari_stram.h>
 #endif
@@ -44,31 +44,222 @@ unsigned long mm_cachebits;
 EXPORT_SYMBOL(mm_cachebits);
 #endif
 
+/* Prior to calling these routines, the page should have been flushed
+ * from both the cache and ATC, or the CPU might not notice that the
+ * cache setting for the page has been changed. -jskov
+ */
+static inline void nocache_page(void *vaddr)
+{
+	unsigned long addr = (unsigned long)vaddr;
+
+	if (CPU_IS_040_OR_060) {
+		pte_t *ptep = virt_to_kpte(addr);
+
+		*ptep = pte_mknocache(*ptep);
+	}
+}
+
+static inline void cache_page(void *vaddr)
+{
+	unsigned long addr = (unsigned long)vaddr;
+
+	if (CPU_IS_040_OR_060) {
+		pte_t *ptep = virt_to_kpte(addr);
+
+		*ptep = pte_mkcache(*ptep);
+	}
+}
+
+/*
+ * Motorola 680x0 user's manual recommends using uncached memory for address
+ * translation tables.
+ *
+ * Seeing how the MMU can be external on (some of) these chips, that seems like
+ * a very important recommendation to follow. Provide some helpers to combat
+ * 'variation' amongst the users of this.
+ */
+
+void mmu_page_ctor(void *page)
+{
+	__flush_pages_to_ram(page, 1);
+	flush_tlb_kernel_page(page);
+	nocache_page(page);
+}
+
+void mmu_page_dtor(void *page)
+{
+	cache_page(page);
+}
+
+/* ++andreas: {get,free}_pointer_table rewritten to use unused fields from
+   struct ptdesc instead of separately kmalloced struct.  Stolen from
+   arch/sparc/mm/srmmu.c ... */
+
+typedef struct list_head ptable_desc;
+
+static struct list_head ptable_list[3] = {
+	LIST_HEAD_INIT(ptable_list[0]),
+	LIST_HEAD_INIT(ptable_list[1]),
+	LIST_HEAD_INIT(ptable_list[2]),
+};
+
+#define PD_PTABLE(ptdesc) ((ptable_desc *)&(virt_to_ptdesc((void *)(ptdesc))->pt_list))
+#define PD_PTDESC(ptable) (list_entry(ptable, struct ptdesc, pt_list))
+#define PD_MARKBITS(dp) (*(unsigned int *)&PD_PTDESC(dp)->pt_index)
+
+static const int ptable_shift[3] = {
+	7+2, /* PGD */
+	7+2, /* PMD */
+	6+2, /* PTE */
+};
+
+#define ptable_size(type) (1U << ptable_shift[type])
+#define ptable_mask(type) ((1U << (PAGE_SIZE / ptable_size(type))) - 1)
+
+void __init init_pointer_table(void *table, int type)
+{
+	ptable_desc *dp;
+	unsigned long ptable = (unsigned long)table;
+	unsigned long pt_addr = ptable & PAGE_MASK;
+	unsigned int mask = 1U << ((ptable - pt_addr)/ptable_size(type));
+
+	dp = PD_PTABLE(pt_addr);
+	if (!(PD_MARKBITS(dp) & mask)) {
+		PD_MARKBITS(dp) = ptable_mask(type);
+		list_add(dp, &ptable_list[type]);
+	}
+
+	PD_MARKBITS(dp) &= ~mask;
+	pr_debug("init_pointer_table: %lx, %x\n", ptable, PD_MARKBITS(dp));
+
+	/* unreserve the ptdesc so it's possible to free that ptdesc */
+	__ClearPageReserved(ptdesc_page(PD_PTDESC(dp)));
+	init_page_count(ptdesc_page(PD_PTDESC(dp)));
+
+	return;
+}
+
+void *get_pointer_table(struct mm_struct *mm, int type)
+{
+	ptable_desc *dp = ptable_list[type].next;
+	unsigned int mask = list_empty(&ptable_list[type]) ? 0 : PD_MARKBITS(dp);
+	unsigned int tmp, off;
+
+	/*
+	 * For a pointer table for a user process address space, a
+	 * table is taken from a ptdesc allocated for the purpose.  Each
+	 * ptdesc can hold 8 pointer tables.  The ptdesc is remapped in
+	 * virtual address space to be noncacheable.
+	 */
+	if (mask == 0) {
+		struct ptdesc *ptdesc;
+		ptable_desc *new;
+		void *pt_addr;
+
+		ptdesc = pagetable_alloc(GFP_KERNEL | __GFP_ZERO, 0);
+		if (!ptdesc)
+			return NULL;
+
+		pt_addr = ptdesc_address(ptdesc);
+
+		switch (type) {
+		case TABLE_PTE:
+			/*
+			 * m68k doesn't have SPLIT_PTE_PTLOCKS for not having
+			 * SMP.
+			 */
+			pagetable_pte_ctor(mm, ptdesc);
+			break;
+		case TABLE_PMD:
+			pagetable_pmd_ctor(mm, ptdesc);
+			break;
+		case TABLE_PGD:
+			pagetable_pgd_ctor(ptdesc);
+			break;
+		}
+
+		mmu_page_ctor(pt_addr);
+
+		new = PD_PTABLE(pt_addr);
+		PD_MARKBITS(new) = ptable_mask(type) - 1;
+		list_add_tail(new, dp);
+
+		return (pmd_t *)pt_addr;
+	}
+
+	for (tmp = 1, off = 0; (mask & tmp) == 0; tmp <<= 1, off += ptable_size(type))
+		;
+	PD_MARKBITS(dp) = mask & ~tmp;
+	if (!PD_MARKBITS(dp)) {
+		/* move to end of list */
+		list_move_tail(dp, &ptable_list[type]);
+	}
+	return ptdesc_address(PD_PTDESC(dp)) + off;
+}
+
+int free_pointer_table(void *table, int type)
+{
+	ptable_desc *dp;
+	unsigned long ptable = (unsigned long)table;
+	unsigned long pt_addr = ptable & PAGE_MASK;
+	unsigned int mask = 1U << ((ptable - pt_addr)/ptable_size(type));
+
+	dp = PD_PTABLE(pt_addr);
+	if (PD_MARKBITS (dp) & mask)
+		panic ("table already free!");
+
+	PD_MARKBITS (dp) |= mask;
+
+	if (PD_MARKBITS(dp) == ptable_mask(type)) {
+		/* all tables in ptdesc are free, free ptdesc */
+		list_del(dp);
+		mmu_page_dtor((void *)pt_addr);
+		pagetable_dtor_free(virt_to_ptdesc((void *)pt_addr));
+		return 1;
+	} else if (ptable_list[type].next != dp) {
+		/*
+		 * move this descriptor to the front of the list, since
+		 * it has one or more free tables.
+		 */
+		list_move(dp, &ptable_list[type]);
+	}
+	return 0;
+}
+
 /* size of memory already mapped in head.S */
-#define INIT_MAPPED_SIZE	(4UL<<20)
+extern __initdata unsigned long m68k_init_mapped_size;
 
 extern unsigned long availmem;
 
+static pte_t *last_pte_table __initdata = NULL;
+
 static pte_t * __init kernel_page_table(void)
 {
-	pte_t *ptablep;
+	pte_t *pte_table = last_pte_table;
+
+	if (PAGE_ALIGNED(last_pte_table)) {
+		pte_table = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
+		if (!pte_table) {
+			panic("%s: Failed to allocate %lu bytes align=%lx\n",
+					__func__, PAGE_SIZE, PAGE_SIZE);
+		}
+
+		clear_page(pte_table);
+		mmu_page_ctor(pte_table);
 
-	ptablep = (pte_t *)alloc_bootmem_low_pages(PAGE_SIZE);
+		last_pte_table = pte_table;
+	}
 
-	clear_page(ptablep);
-	__flush_page_to_ram(ptablep);
-	flush_tlb_kernel_page(ptablep);
-	nocache_page(ptablep);
+	last_pte_table += PTRS_PER_PTE;
 
-	return ptablep;
+	return pte_table;
 }
 
-static pmd_t *last_pgtable __initdata = NULL;
-pmd_t *zero_pgtable __initdata = NULL;
+static pmd_t *last_pmd_table __initdata = NULL;
 
 static pmd_t * __init kernel_ptr_table(void)
 {
-	if (!last_pgtable) {
+	if (!last_pmd_table) {
 		unsigned long pmd, last;
 		int i;
 
@@ -78,38 +269,41 @@ static pmd_t * __init kernel_ptr_table(void)
 		 */
 		last = (unsigned long)kernel_pg_dir;
 		for (i = 0; i < PTRS_PER_PGD; i++) {
-			if (!pgd_present(kernel_pg_dir[i]))
+			pud_t *pud = (pud_t *)(&kernel_pg_dir[i]);
+
+			if (!pud_present(*pud))
 				continue;
-			pmd = __pgd_page(kernel_pg_dir[i]);
+			pmd = pgd_page_vaddr(kernel_pg_dir[i]);
 			if (pmd > last)
 				last = pmd;
 		}
 
-		last_pgtable = (pmd_t *)last;
+		last_pmd_table = (pmd_t *)last;
 #ifdef DEBUG
-		printk("kernel_ptr_init: %p\n", last_pgtable);
+		printk("kernel_ptr_init: %p\n", last_pmd_table);
 #endif
 	}
 
-	last_pgtable += PTRS_PER_PMD;
-	if (((unsigned long)last_pgtable & ~PAGE_MASK) == 0) {
-		last_pgtable = (pmd_t *)alloc_bootmem_low_pages(PAGE_SIZE);
+	last_pmd_table += PTRS_PER_PMD;
+	if (PAGE_ALIGNED(last_pmd_table)) {
+		last_pmd_table = memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
+		if (!last_pmd_table)
+			panic("%s: Failed to allocate %lu bytes align=%lx\n",
+			      __func__, PAGE_SIZE, PAGE_SIZE);
 
-		clear_page(last_pgtable);
-		__flush_page_to_ram(last_pgtable);
-		flush_tlb_kernel_page(last_pgtable);
-		nocache_page(last_pgtable);
+		clear_page(last_pmd_table);
+		mmu_page_ctor(last_pmd_table);
 	}
 
-	return last_pgtable;
+	return last_pmd_table;
 }
 
 static void __init map_node(int node)
 {
-#define PTRTREESIZE (256*1024)
-#define ROOTTREESIZE (32*1024*1024)
 	unsigned long physaddr, virtaddr, size;
 	pgd_t *pgd_dir;
+	p4d_t *p4d_dir;
+	pud_t *pud_dir;
 	pmd_t *pmd_dir;
 	pte_t *pte_dir;
 
@@ -123,56 +317,57 @@ static void __init map_node(int node)
 
 	while (size > 0) {
 #ifdef DEBUG
-		if (!(virtaddr & (PTRTREESIZE-1)))
+		if (!(virtaddr & (PMD_SIZE-1)))
 			printk ("\npa=%#lx va=%#lx ", physaddr & PAGE_MASK,
 				virtaddr);
 #endif
 		pgd_dir = pgd_offset_k(virtaddr);
 		if (virtaddr && CPU_IS_020_OR_030) {
-			if (!(virtaddr & (ROOTTREESIZE-1)) &&
-			    size >= ROOTTREESIZE) {
+			if (!(virtaddr & (PGDIR_SIZE-1)) &&
+			    size >= PGDIR_SIZE) {
 #ifdef DEBUG
 				printk ("[very early term]");
 #endif
 				pgd_val(*pgd_dir) = physaddr;
-				size -= ROOTTREESIZE;
-				virtaddr += ROOTTREESIZE;
-				physaddr += ROOTTREESIZE;
+				size -= PGDIR_SIZE;
+				virtaddr += PGDIR_SIZE;
+				physaddr += PGDIR_SIZE;
 				continue;
 			}
 		}
-		if (!pgd_present(*pgd_dir)) {
+		p4d_dir = p4d_offset(pgd_dir, virtaddr);
+		pud_dir = pud_offset(p4d_dir, virtaddr);
+		if (!pud_present(*pud_dir)) {
 			pmd_dir = kernel_ptr_table();
 #ifdef DEBUG
 			printk ("[new pointer %p]", pmd_dir);
 #endif
-			pgd_set(pgd_dir, pmd_dir);
+			pud_set(pud_dir, pmd_dir);
 		} else
-			pmd_dir = pmd_offset(pgd_dir, virtaddr);
+			pmd_dir = pmd_offset(pud_dir, virtaddr);
 
 		if (CPU_IS_020_OR_030) {
 			if (virtaddr) {
 #ifdef DEBUG
 				printk ("[early term]");
 #endif
-				pmd_dir->pmd[(virtaddr/PTRTREESIZE) & 15] = physaddr;
-				physaddr += PTRTREESIZE;
+				pmd_val(*pmd_dir) = physaddr;
+				physaddr += PMD_SIZE;
 			} else {
 				int i;
 #ifdef DEBUG
 				printk ("[zero map]");
 #endif
-				zero_pgtable = kernel_ptr_table();
-				pte_dir = (pte_t *)zero_pgtable;
-				pmd_dir->pmd[0] = virt_to_phys(pte_dir) |
-					_PAGE_TABLE | _PAGE_ACCESSED;
+				pte_dir = kernel_page_table();
+				pmd_set(pmd_dir, pte_dir);
+
 				pte_val(*pte_dir++) = 0;
 				physaddr += PAGE_SIZE;
-				for (i = 1; i < 64; physaddr += PAGE_SIZE, i++)
+				for (i = 1; i < PTRS_PER_PTE; physaddr += PAGE_SIZE, i++)
 					pte_val(*pte_dir++) = physaddr;
 			}
-			size -= PTRTREESIZE;
-			virtaddr += PTRTREESIZE;
+			size -= PMD_SIZE;
+			virtaddr += PMD_SIZE;
 		} else {
 			if (!pmd_present(*pmd_dir)) {
 #ifdef DEBUG
@@ -200,14 +395,43 @@ static void __init map_node(int node)
 }
 
 /*
+ * Alternate definitions that are compile time constants, for
+ * initializing protection_map.  The cachebits are fixed later.
+ */
+#define PAGE_NONE_C	__pgprot(_PAGE_PROTNONE | _PAGE_ACCESSED)
+#define PAGE_SHARED_C	__pgprot(_PAGE_PRESENT | _PAGE_ACCESSED)
+#define PAGE_COPY_C	__pgprot(_PAGE_PRESENT | _PAGE_RONLY | _PAGE_ACCESSED)
+#define PAGE_READONLY_C	__pgprot(_PAGE_PRESENT | _PAGE_RONLY | _PAGE_ACCESSED)
+
+static pgprot_t protection_map[16] __ro_after_init = {
+	[VM_NONE]					= PAGE_NONE_C,
+	[VM_READ]					= PAGE_READONLY_C,
+	[VM_WRITE]					= PAGE_COPY_C,
+	[VM_WRITE | VM_READ]				= PAGE_COPY_C,
+	[VM_EXEC]					= PAGE_READONLY_C,
+	[VM_EXEC | VM_READ]				= PAGE_READONLY_C,
+	[VM_EXEC | VM_WRITE]				= PAGE_COPY_C,
+	[VM_EXEC | VM_WRITE | VM_READ]			= PAGE_COPY_C,
+	[VM_SHARED]					= PAGE_NONE_C,
+	[VM_SHARED | VM_READ]				= PAGE_READONLY_C,
+	[VM_SHARED | VM_WRITE]				= PAGE_SHARED_C,
+	[VM_SHARED | VM_WRITE | VM_READ]		= PAGE_SHARED_C,
+	[VM_SHARED | VM_EXEC]				= PAGE_READONLY_C,
+	[VM_SHARED | VM_EXEC | VM_READ]			= PAGE_READONLY_C,
+	[VM_SHARED | VM_EXEC | VM_WRITE]		= PAGE_SHARED_C,
+	[VM_SHARED | VM_EXEC | VM_WRITE | VM_READ]	= PAGE_SHARED_C
+};
+DECLARE_VM_GET_PAGE_PROT
+
+/*
  * paging_init() continues the virtual memory environment setup which
  * was begun by the code in arch/head.S.
  */
 void __init paging_init(void)
 {
-	unsigned long zones_size[MAX_NR_ZONES] = { 0, };
+	unsigned long max_zone_pfn[MAX_NR_ZONES] = { 0, };
 	unsigned long min_addr, max_addr;
-	unsigned long addr, size, end;
+	unsigned long addr;
 	int i;
 
 #ifdef DEBUG
@@ -225,7 +449,9 @@ void __init paging_init(void)
 	}
 
 	min_addr = m68k_memory[0].addr;
-	max_addr = min_addr + m68k_memory[0].size;
+	max_addr = min_addr + m68k_memory[0].size - 1;
+	memblock_add_node(m68k_memory[0].addr, m68k_memory[0].size, 0,
+			  MEMBLOCK_NONE);
 	for (i = 1; i < m68k_num_memory;) {
 		if (m68k_memory[i].addr < min_addr) {
 			printk("Ignoring memory chunk at 0x%lx:0x%lx before the first chunk\n",
@@ -233,74 +459,64 @@ void __init paging_init(void)
 			printk("Fix your bootloader or use a memfile to make use of this area!\n");
 			m68k_num_memory--;
 			memmove(m68k_memory + i, m68k_memory + i + 1,
-				(m68k_num_memory - i) * sizeof(struct mem_info));
+				(m68k_num_memory - i) * sizeof(struct m68k_mem_info));
 			continue;
 		}
-		addr = m68k_memory[i].addr + m68k_memory[i].size;
+		memblock_add_node(m68k_memory[i].addr, m68k_memory[i].size, i,
+				  MEMBLOCK_NONE);
+		addr = m68k_memory[i].addr + m68k_memory[i].size - 1;
 		if (addr > max_addr)
 			max_addr = addr;
 		i++;
 	}
 	m68k_memoffset = min_addr - PAGE_OFFSET;
-	m68k_virt_to_node_shift = fls(max_addr - min_addr - 1) - 6;
+	m68k_virt_to_node_shift = fls(max_addr - min_addr) - 6;
 
 	module_fixup(NULL, __start_fixup, __stop_fixup);
 	flush_icache();
 
-	high_memory = phys_to_virt(max_addr);
+	high_memory = phys_to_virt(max_addr) + 1;
 
 	min_low_pfn = availmem >> PAGE_SHIFT;
-	max_low_pfn = max_addr >> PAGE_SHIFT;
+	max_pfn = max_low_pfn = (max_addr >> PAGE_SHIFT) + 1;
 
-	for (i = 0; i < m68k_num_memory; i++) {
-		addr = m68k_memory[i].addr;
-		end = addr + m68k_memory[i].size;
-		m68k_setup_node(i);
-		availmem = PAGE_ALIGN(availmem);
-		availmem += init_bootmem_node(NODE_DATA(i),
-					      availmem >> PAGE_SHIFT,
-					      addr >> PAGE_SHIFT,
-					      end >> PAGE_SHIFT);
-	}
+	/* Reserve kernel text/data/bss and the memory allocated in head.S */
+	memblock_reserve(m68k_memory[0].addr, availmem - m68k_memory[0].addr);
 
 	/*
 	 * Map the physical memory available into the kernel virtual
-	 * address space. First initialize the bootmem allocator with
-	 * the memory we already mapped, so map_node() has something
-	 * to allocate.
+	 * address space. Make sure memblock will not try to allocate
+	 * pages beyond the memory we already mapped in head.S
 	 */
-	addr = m68k_memory[0].addr;
-	size = m68k_memory[0].size;
-	free_bootmem_node(NODE_DATA(0), availmem, min(INIT_MAPPED_SIZE, size) - (availmem - addr));
-	map_node(0);
-	if (size > INIT_MAPPED_SIZE)
-		free_bootmem_node(NODE_DATA(0), addr + INIT_MAPPED_SIZE, size - INIT_MAPPED_SIZE);
-
-	for (i = 1; i < m68k_num_memory; i++)
+	memblock_set_bottom_up(true);
+
+	for (i = 0; i < m68k_num_memory; i++) {
+		m68k_setup_node(i);
 		map_node(i);
+	}
 
 	flush_tlb_all();
 
+	early_memtest(min_addr, max_addr);
+
 	/*
 	 * initialize the bad page table and bad page to point
 	 * to a couple of allocated pages
 	 */
-	empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
+	empty_zero_page = memblock_alloc_or_panic(PAGE_SIZE, PAGE_SIZE);
 
 	/*
 	 * Set up SFC/DFC registers
 	 */
-	set_fs(KERNEL_DS);
+	set_fc(USER_DATA);
 
 #ifdef DEBUG
 	printk ("before free_area_init\n");
 #endif
-	for (i = 0; i < m68k_num_memory; i++) {
-		zones_size[ZONE_DMA] = m68k_memory[i].size >> PAGE_SHIFT;
-		free_area_init_node(i, zones_size,
-				    m68k_memory[i].addr >> PAGE_SHIFT, NULL);
+	for (i = 0; i < m68k_num_memory; i++)
 		if (node_present_pages(i))
 			node_set_state(i, N_NORMAL_MEMORY);
-	}
-}
 
+	max_zone_pfn[ZONE_DMA] = memblock_end_of_DRAM();
+	free_area_init(max_zone_pfn);
+}