patch-2.4.0-test12 linux/arch/parisc/mm/init.c

• Lines: 480
• Date: Tue Dec 5 12:29:39 2000
• Orig file: v2.4.0-test11/linux/arch/parisc/mm/init.c
• Orig date: Wed Dec 31 16:00:00 1969

diff -u --recursive --new-file v2.4.0-test11/linux/arch/parisc/mm/init.c linux/arch/parisc/mm/init.c
@@ -0,0 +1,479 @@
+/*
+ *  linux/arch/parisc/mm/init.c
+ *
+ *  Copyright (C) 1995	Linus Torvalds
+ *  Copyright 1999 SuSE GmbH
+ *    changed by Philipp Rumpf
+ *  Copyright 1999 Philipp Rumpf (prumpf@tux.org)
+ *
+ */
+
+#include <linux/config.h>
+
+#include <linux/mm.h>
+#include <linux/bootmem.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/pci.h>		/* for hppa_dma_ops and pcxl_dma_ops */
+#include <linux/swap.h>
+#include <linux/unistd.h>
+
+#include <asm/pgalloc.h>
+
+static unsigned long totalram_pages;
+extern unsigned long max_pfn, mem_max;
+
+void free_initmem(void)  {
+}
+
+/*
+ * Just an arbitrary offset to serve as a "hole" between mapping areas
+ * (between top of physical memory and a potential pcxl dma mapping
+ * area, and below the vmalloc mapping area).
+ *
+ * The current 32K value just means that there will be a 32K "hole"
+ * between mapping areas. That means that  any out-of-bounds memory
+ * accesses will hopefully be caught. The vmalloc() routines leaves
+ * a hole of 4kB between each vmalloced area for the same reason.
+ */
+
+#define VM_MAP_OFFSET  (32*1024)
+#define SET_MAP_OFFSET(x) ((void *)(((unsigned long)(x) + VM_MAP_OFFSET) \
+				     & ~(VM_MAP_OFFSET-1)))
+
+void *vmalloc_start;
+unsigned long pcxl_dma_start;
+
+void __init mem_init(void)
+{
+	max_mapnr = num_physpages = max_low_pfn;
+	high_memory = __va(max_low_pfn * PAGE_SIZE);
+
+	totalram_pages += free_all_bootmem();
+	printk("Memory: %luk available\n", totalram_pages << (PAGE_SHIFT-10));
+
+	if (hppa_dma_ops == &pcxl_dma_ops) {
+	    pcxl_dma_start = (unsigned long)SET_MAP_OFFSET(high_memory);
+	    vmalloc_start = SET_MAP_OFFSET(pcxl_dma_start + PCXL_DMA_MAP_SIZE);
+	}
+	else {
+	    pcxl_dma_start = 0;
+	    vmalloc_start = SET_MAP_OFFSET(high_memory);
+	}
+}
+
+void __bad_pgd(pgd_t *pgd)
+{
+	printk("Bad pgd in pmd_alloc: %08lx\n", pgd_val(*pgd));
+	pgd_val(*pgd) = _PAGE_TABLE + __pa(BAD_PAGETABLE);
+}
+
+void __bad_pmd(pmd_t *pmd)
+{
+	printk("Bad pmd in pte_alloc: %08lx\n", pmd_val(*pmd));
+	pmd_val(*pmd) = _PAGE_TABLE + __pa(BAD_PAGETABLE);
+}
+
+pte_t *get_pte_slow(pmd_t *pmd, unsigned long offset)
+{
+	pte_t *pte;
+
+	pte = (pte_t *) __get_free_page(GFP_KERNEL);
+
+	if (pmd_none(*pmd)) {
+		if (pte) {
+			clear_page(pte);
+			pmd_val(*pmd) = _PAGE_TABLE + __pa((unsigned long)pte);
+			return pte + offset;
+		}
+		pmd_val(*pmd) = _PAGE_TABLE + __pa(BAD_PAGETABLE);
+		return NULL;
+	}
+
+	free_page((unsigned long)pte);
+
+	if (pmd_bad(*pmd)) {
+		__bad_pmd(pmd);
+		return NULL;
+	}
+
+	return (pte_t *) pmd_page(*pmd) + offset;
+}
+
+int do_check_pgt_cache(int low, int high)
+{
+	return 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.
+ */
+pte_t * __bad_pagetable(void)
+{
+	return (pte_t *) NULL;
+}
+
+unsigned long *empty_zero_page;
+unsigned long *empty_bad_page;
+
+pte_t __bad_page(void)
+{
+	return *(pte_t *)NULL;
+}
+
+void show_mem(void)
+{
+	int i,free = 0,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 (!atomic_read(&mem_map[i].count))
+			free++;
+		else
+			shared += atomic_read(&mem_map[i].count) - 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();
+}
+
+void set_pte_phys (unsigned long vaddr, unsigned long phys)
+{
+}
+
+
+/*
+ * pagetable_init() sets up the page tables
+ *
+ * Note that gateway_init() places the Linux gateway page at page 0.
+ * Since gateway pages cannot be dereferenced this has the desirable
+ * side effect of trapping those pesky NULL-reference errors in the
+ * kernel.
+ */
+static void __init pagetable_init(void)
+{
+	pgd_t *pg_dir;
+	pmd_t *pmd;
+	pte_t *pg_table;
+	unsigned long tmp1;
+	unsigned long tmp2;
+	unsigned long address;
+	unsigned long ro_start;
+	unsigned long ro_end;
+	unsigned long fv_addr;
+	extern  const int stext;
+	extern  int data_start;
+	extern  const unsigned long fault_vector_20;
+
+	ro_start = __pa((unsigned long)&stext);
+	ro_end   = __pa((unsigned long)&data_start);
+	fv_addr  = __pa((unsigned long)&fault_vector_20) & PAGE_MASK;
+
+	printk("pagetable_init\n");
+
+	/* Map whole memory from PAGE_OFFSET */
+	pg_dir = (pgd_t *)swapper_pg_dir + USER_PGD_PTRS;
+
+	address = 0;
+	while (address < mem_max) {
+		/* XXX: BTLB should be done here */
+
+#if PTRS_PER_PMD == 1
+		pmd = (pmd_t *)__pa(pg_dir);
+#else
+		pmd = (pmd_t *) (PAGE_MASK & pgd_val(*pg_dir));
+
+		/*
+		 * pmd is physical at this point
+		 */
+
+		if (!pmd) {
+			pmd = (pmd_t *) alloc_bootmem_low_pages(PAGE_SIZE);
+			pmd = (pmd_t *) __pa(pmd);
+		}
+
+		pgd_val(*pg_dir) = _PAGE_TABLE | (unsigned long) pmd;
+#endif
+		pg_dir++;
+
+		/* now change pmd to kernel virtual addresses */
+
+		pmd = (pmd_t *) __va(pmd);
+		for (tmp1 = 0 ; tmp1 < PTRS_PER_PMD ; tmp1++,pmd++) {
+
+			/*
+			 * pg_table is physical at this point
+			 */
+
+			pg_table = (pte_t *) (PAGE_MASK & pmd_val(*pmd));
+			if (!pg_table) {
+				pg_table = (pte_t *)
+					alloc_bootmem_low_pages(PAGE_SIZE);
+				pg_table = (pte_t *) __pa(pg_table);
+			}
+
+			pmd_val(*pmd) = _PAGE_TABLE |
+					   (unsigned long) pg_table;
+
+			/* now change pg_table to kernel virtual addresses */
+
+			pg_table = (pte_t *) __va(pg_table);
+			for (tmp2=0; tmp2 < PTRS_PER_PTE; tmp2++,pg_table++) {
+				pte_t pte;
+
+#if !defined(CONFIG_KWDB) && !defined(CONFIG_STI_CONSOLE)
+#warning STI console should explicitly allocate executable pages but does not
+/* KWDB needs to write kernel text when setting break points.
+**
+** The right thing to do seems like KWDB modify only the pte which
+** has a break point on it...otherwise we might mask worse bugs.
+*/
+				if (address >= ro_start && address < ro_end
+							&& address != fv_addr)
+				    pte = __mk_pte(address, PAGE_KERNEL_RO);
+				else
+#endif
+				    pte = __mk_pte(address, PAGE_KERNEL);
+
+				if (address >= mem_max)
+					pte_val(pte) = 0;
+
+				set_pte(pg_table, pte);
+
+				address += PAGE_SIZE;
+			}
+
+			if (address >= mem_max)
+			    break;
+		}
+	}
+
+	empty_zero_page = alloc_bootmem_pages(PAGE_SIZE);
+	memset(empty_zero_page, 0, PAGE_SIZE);
+}
+
+unsigned long gateway_pgd_offset;
+unsigned long gateway_pgd_entry;
+
+static void __init gateway_init(void)
+{
+	unsigned long hpux_gateway_page_addr;
+	unsigned long linux_gateway_page_addr;
+	pgd_t *pg_dir;
+	pmd_t *pmd_base;
+	pmd_t *pmd;
+	pte_t *pg_table_base;
+	pte_t *pg_table;
+	/* FIXME: These are 'const' in order to trick the compiler
+           into not treating them as DP-relative data. */
+	extern void * const hpux_gateway_page;
+	extern void * const linux_gateway_page;
+	pte_t pte;
+
+	hpux_gateway_page_addr = HPUX_GATEWAY_ADDR & PAGE_MASK;
+	linux_gateway_page_addr = LINUX_GATEWAY_ADDR & PAGE_MASK;
+
+	gateway_pgd_offset = hpux_gateway_page_addr >> PGDIR_SHIFT;
+
+	/*
+	 * Setup Linux Gateway page.
+	 *
+	 * The Linux gateway page will reside in kernel space (on virtual
+	 * page 0), so it doesn't need to be aliased into user space.
+	 */
+
+	pg_dir = (pgd_t *)swapper_pg_dir;
+
+#if PTRS_PER_PMD == 1
+	pmd_base = (pmd_t *)pg_dir;
+	pmd = pmd_base +
+		((linux_gateway_page_addr) >> PGDIR_SHIFT);
+
+#else
+	pmd_base = (pmd_t *) alloc_bootmem_pages(PAGE_SIZE);
+	pgd_val(*(pg_dir + (linux_gateway_page_addr >> PGDIR_SHIFT))) =
+		_PAGE_TABLE | __pa(pmd_base);
+
+	pmd = pmd_base +
+		((linux_gateway_page_addr & (PMD_MASK) & (PGDIR_SIZE - 1)) >>
+								PMD_SHIFT);
+#endif
+
+	pg_table_base = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
+
+	pmd_val(*pmd) = _PAGE_TABLE | __pa(pg_table_base);
+
+	pte = __mk_pte(__pa(&linux_gateway_page), PAGE_GATEWAY);
+
+	pg_table = pg_table_base +
+		((linux_gateway_page_addr & (PAGE_MASK) & (PMD_SIZE - 1)) >>
+								PAGE_SHIFT);
+
+	set_pte(pg_table,pte);
+
+	/*
+	 * Setup HP-UX gateway page.
+	 * This page will be aliased into each user address space.
+	 */
+
+	pg_table_base = (pte_t *) alloc_bootmem_pages(PAGE_SIZE);
+
+	pte = __mk_pte(__pa(&hpux_gateway_page), PAGE_GATEWAY);
+	pg_table = pg_table_base +
+		((hpux_gateway_page_addr & (PAGE_MASK) & (PMD_SIZE - 1)) >>
+								PAGE_SHIFT);
+
+	set_pte(pg_table,pte);
+
+
+#if PTRS_PER_PMD == 1
+	pmd_base = (pmd_t *)pg_table_base;
+#else
+	pmd_base = (pmd_t *) alloc_bootmem_pages(PAGE_SIZE);
+	pmd = pmd_base +
+		((hpux_gateway_page_addr & (PMD_MASK) & (PGDIR_SIZE - 1)) >>
+								PMD_SHIFT);
+	pmd_val(*pmd) = _PAGE_TABLE | __pa(pg_table_base);
+#endif
+
+	gateway_pgd_entry = _PAGE_TABLE | __pa(pmd_base);
+
+	/*
+	 * We will be aliasing the HP-UX gateway page into all HP-UX
+	 * user spaces at the same address (not counting the space register
+	 * value) that will be equivalently mapped as long as space register
+	 * hashing is disabled. It will be a problem if anyone touches
+	 * the gateway pages at its "kernel" address, since that is
+	 * NOT equivalently mapped. We'll flush the caches at this
+	 * point, just in case some code has touched those addresses
+	 * previous to this, but all bets are off if they get touched
+	 * after this point.
+	 */
+
+	flush_all_caches();
+
+	return;
+}
+
+void __init paging_init(void)
+{
+	pagetable_init();
+	gateway_init();
+
+	{
+		unsigned long zones_size[MAX_NR_ZONES] = { max_pfn/2, max_pfn/2, };
+
+		free_area_init(zones_size);
+	}
+}
+
+#define NR_SPACE_IDS	8192
+
+static unsigned long space_id[NR_SPACE_IDS / (8 * sizeof(long))];
+static unsigned long space_id_index;
+static unsigned long free_space_ids = NR_SPACE_IDS;
+
+/*
+ * XXX: We should probably unfold the set_bit / test_bit / clear_bit
+ * locking out of these two functions and have a single spinlock on the
+ * space_id data structures.
+ *
+ * Don't bother. This is all going to be significantly changed in the
+ * very near future.
+ */
+
+#define SPACEID_SHIFT (PAGE_SHIFT + (PT_NLEVELS)*(PAGE_SHIFT - PT_NLEVELS) - 32)
+
+unsigned long alloc_sid(void)
+{
+	unsigned long index;
+
+	if (free_space_ids == 0)
+		BUG();
+
+	free_space_ids--;
+
+	do {
+		index = find_next_zero_bit(space_id, NR_SPACE_IDS, space_id_index);
+	} while(test_and_set_bit(index, space_id));
+
+	space_id_index = index;
+
+	return index << SPACEID_SHIFT;
+}
+
+void free_sid(unsigned long spaceid)
+{
+	unsigned long index = spaceid >> SPACEID_SHIFT;
+	if (index < 0)
+		BUG();
+
+	clear_bit(index, space_id);
+
+	if (space_id_index > index) {
+		space_id_index = index;
+	}
+	free_space_ids++;
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+#if 0
+	for (; start < end; start += PAGE_SIZE) {
+		ClearPageReserved(mem_map + MAP_NR(start));
+		set_page_count(mem_map+MAP_NR(start), 1);
+		free_page(start);
+		totalram_pages++;
+	}
+	printk ("Freeing initrd memory: %ldk freed\n", (end - start) >> 10);
+#endif
+}
+#endif
+
+void si_meminfo(struct sysinfo *val)
+{
+	int i;
+
+	i = max_mapnr;
+	val->totalram = totalram_pages;
+	val->sharedram = 0;
+	val->freeram = nr_free_pages();
+	val->bufferram = atomic_read(&buffermem_pages);
+#if 0
+	while (i-- > 0)  {
+		if (PageReserved(mem_map+i))
+			continue;
+		val->totalram++;
+		if (!atomic_read(&mem_map[i].count))
+			continue;
+		val->sharedram += atomic_read(&mem_map[i].count) - 1;
+	}
+	val->totalram <<= PAGE_SHIFT;
+	val->sharedram <<= PAGE_SHIFT;
+#endif
+	val->totalhigh = 0;
+	val->freehigh = 0;
+	return;
+}