patch-2.4.22 linux-2.4.22/arch/sh64/mm/init.c

• Lines: 204
• Date: 2003-08-25 04:44:40.000000000 -0700
• Orig file: linux-2.4.21/arch/sh64/mm/init.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.21/arch/sh64/mm/init.c linux-2.4.22/arch/sh64/mm/init.c
@@ -0,0 +1,203 @@
+/*
+ * This file is subject to the terms and conditions of the GNU General Public
+ * License.  See the file "COPYING" in the main directory of this archive
+ * for more details.
+ *
+ * arch/sh64/mm/init.c
+ *
+ * Copyright (C) 2000, 2001  Paolo Alberelli
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/swap.h>
+#include <linux/bootmem.h>
+#include <linux/highmem.h>
+
+#include <asm/mmu_context.h>
+#include <asm/page.h>
+#include <asm/pgalloc.h>
+#include <asm/pgtable.h>
+#include <asm/tlb.h>
+
+#ifdef CONFIG_BLK_DEV_INITRD
+#include <linux/blk.h>
+#endif
+
+mmu_gather_t mmu_gathers[NR_CPUS];
+
+/*
+ * Cache of MMU context last used.
+ */
+unsigned long mmu_context_cache;
+pgd_t * mmu_pdtp_cache;
+
+static unsigned long totalram_pages = 0;
+static unsigned long totalhigh_pages = 0;
+
+/*
+ * BAD_PAGE is the page that is used for page faults when linux
+ * is out-of-memory. Older versions of linux just did a
+ * do_exit(), but using this instead means there is less risk
+ * for a process dying in kernel mode, possibly leaving an inode
+ * unused etc..
+ *
+ * BAD_PAGETABLE is the accompanying page-table: it is initialized
+ * to point to BAD_PAGE entries.
+ *
+ * ZERO_PAGE is a special page that is used for zero-initialized
+ * data and COW.
+ */
+
+extern unsigned char empty_zero_page[PAGE_SIZE];
+extern unsigned char empty_bad_page[PAGE_SIZE];
+extern pte_t empty_bad_pte_table[PTRS_PER_PTE];
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+
+extern char _text, _etext, _edata, __bss_start, _end;
+extern char __init_begin, __init_end;
+
+/* It'd be good if these lines were in the standard header file. */
+#define START_PFN	(NODE_DATA(0)->bdata->node_boot_start >> PAGE_SHIFT)
+#define MAX_LOW_PFN	(NODE_DATA(0)->bdata->node_low_pfn)
+
+
+void show_mem(void)
+{
+	int i, total = 0, reserved = 0;
+	int shared = 0, cached = 0;
+
+	printk("Mem-info:\n");
+	show_free_areas();
+	printk("Free swap:       %6dkB\n",nr_swap_pages<<(PAGE_SHIFT-10));
+	i = max_mapnr;
+	while (i-- > 0) {
+		total++;
+		if (PageReserved(mem_map+i))
+			reserved++;
+		else if (PageSwapCache(mem_map+i))
+			cached++;
+		else if (page_count(mem_map+i))
+			shared += page_count(mem_map+i) - 1;
+	}
+	printk("%d pages of RAM\n",total);
+	printk("%d reserved pages\n",reserved);
+	printk("%d pages shared\n",shared);
+	printk("%d pages swap cached\n",cached);
+
+	show_buffers();
+}
+
+/*
+ * paging_init() sets up the page tables.
+ *
+ * head.S already did a lot to set up address translation for the kernel.
+ * Here we comes with:
+ * . MMU enabled
+ * . ASID set (SR)
+ * .  some 512MB regions being mapped of which the most relevant here is:
+ *   . CACHED segment (ASID 0 [irrelevant], shared AND NOT user)
+ * . possible variable length regions being mapped as:
+ *   . UNCACHED segment (ASID 0 [irrelevant], shared AND NOT user)
+ * . All of the memory regions are placed, independently from the platform
+ *   on high addresses, above 0x80000000.
+ * . swapper_pg_dir is already cleared out by the .space directive
+ *   in any case swapper does not require a real page directory since
+ *   it's all kernel contained.
+ *
+ * Those pesky NULL-reference errors in the kernel are then
+ * dealt with by not mapping address 0x00000000 at all.
+ *
+ */
+void __init paging_init(void)
+{
+	unsigned long zones_size[MAX_NR_ZONES] = {0, 0, 0};
+
+
+	mmu_context_cache = MMU_CONTEXT_FIRST_VERSION;
+
+        /*
+ 	 * All memory is good as ZONE_NORMAL (fall-through) and ZONE_DMA.
+         */
+	zones_size[ZONE_DMA] = MAX_LOW_PFN - START_PFN;
+
+	free_area_init_node(0, NODE_DATA(0), 0,zones_size, __MEMORY_START, 0);
+}
+
+void __init mem_init(void)
+{
+	int codesize, reservedpages, datasize, initsize;
+	int tmp;
+
+	max_mapnr = num_physpages = MAX_LOW_PFN - START_PFN;
+	high_memory = (void *)__va(MAX_LOW_PFN * PAGE_SIZE);
+
+	/*
+         * Clear the zero-page.
+         * This is not required but we might want to re-use
+         * this very page to pass boot parameters, one day.
+         */
+	memset(empty_zero_page, 0, PAGE_SIZE);
+
+	/* this will put all low memory onto the freelists */
+	totalram_pages += free_all_bootmem();
+	reservedpages = 0;
+	for (tmp = 0; tmp < num_physpages; tmp++)
+		/*
+		 * Only count reserved RAM pages
+		 */
+		if (PageReserved(mem_map+tmp))
+			reservedpages++;
+	codesize =  (unsigned long) &_etext - (unsigned long) &_text;
+	datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
+	initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
+
+	printk("Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, %dk init)\n",
+		(unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
+		max_mapnr << (PAGE_SHIFT-10),
+		codesize >> 10,
+		reservedpages << (PAGE_SHIFT-10),
+		datasize >> 10,
+		initsize >> 10);
+}
+
+void free_initmem(void)
+{
+	unsigned long addr;
+	
+	addr = (unsigned long)(&__init_begin);
+	for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
+		ClearPageReserved(mem_map + MAP_NR(addr));
+		set_page_count(mem_map+MAP_NR(addr), 1);
+		free_page(addr);
+		totalram_pages++;
+	}
+	printk ("Freeing unused kernel memory: %ldk freed\n", (&__init_end - &__init_begin) >> 10);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+	unsigned long p;
+	for (p = start; p < end; p += PAGE_SIZE) {
+		ClearPageReserved(mem_map + MAP_NR(p));
+		set_page_count(mem_map+MAP_NR(p), 1);
+		free_page(p);
+		totalram_pages++;
+	}
+	printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
+}
+#endif
+
+void si_meminfo(struct sysinfo *val)
+{
+	val->totalram = totalram_pages;
+	val->sharedram = 0;
+	val->freeram = nr_free_pages();
+	val->bufferram = atomic_read(&buffermem_pages);
+	val->totalhigh = totalhigh_pages;
+	val->freehigh = nr_free_highpages();
+	val->mem_unit = PAGE_SIZE;
+	return;
+}