patch-2.4.25 linux-2.4.25/arch/ia64/mm/hugetlbpage.c

• Lines: 514
• Date: 2004-02-18 05:36:30.000000000 -0800
• Orig file: linux-2.4.24/arch/ia64/mm/hugetlbpage.c
• Orig date: 1969-12-31 16:00:00.000000000 -0800

diff -urN linux-2.4.24/arch/ia64/mm/hugetlbpage.c linux-2.4.25/arch/ia64/mm/hugetlbpage.c
@@ -0,0 +1,513 @@
+/*
+ * IA-64 Huge TLB Page Support for Kernel.
+ *
+ * Copyright (C) 2002, Rohit Seth <rohit.seth@intel.com>
+ */
+
+#include <linux/config.h>
+#include <linux/init.h>
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/hugetlb.h>
+#include <linux/pagemap.h>
+#include <linux/smp_lock.h>
+#include <linux/slab.h>
+#include <linux/sysctl.h>
+#include <asm/mman.h>
+#include <asm/pgalloc.h>
+#include <asm/tlb.h>
+
+
+#define TASK_HPAGE_BASE (REGION_HPAGE << REGION_SHIFT)
+
+static long    htlbpagemem;
+int     htlbpage_max;
+static long    htlbzone_pages;
+
+struct vm_operations_struct hugetlb_vm_ops;
+static LIST_HEAD(htlbpage_freelist);
+static spinlock_t htlbpage_lock = SPIN_LOCK_UNLOCKED;
+
+static struct page *alloc_hugetlb_page(void)
+{
+	int i;
+	struct page *page;
+
+	spin_lock(&htlbpage_lock);
+	if (list_empty(&htlbpage_freelist)) {
+		spin_unlock(&htlbpage_lock);
+		return NULL;
+	}
+
+	page = list_entry(htlbpage_freelist.next, struct page, list);
+	list_del(&page->list);
+	htlbpagemem--;
+	spin_unlock(&htlbpage_lock);
+	set_page_count(page, 1);
+	for (i = 0; i < (HPAGE_SIZE/PAGE_SIZE); ++i)
+		clear_highpage(&page[i]);
+	return page;
+}
+
+static pte_t *
+huge_pte_alloc (struct mm_struct *mm, unsigned long addr)
+{
+	unsigned long taddr = htlbpage_to_page(addr);
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pte_t *pte = NULL;
+
+	pgd = pgd_offset(mm, taddr);
+	pmd = pmd_alloc(mm, pgd, taddr);
+	if (pmd)
+		pte = pte_alloc(mm, pmd, taddr);
+	return pte;
+}
+
+static pte_t *
+huge_pte_offset (struct mm_struct *mm, unsigned long addr)
+{
+	unsigned long taddr = htlbpage_to_page(addr);
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pte_t *pte = NULL;
+
+	pgd = pgd_offset(mm, taddr);
+	pmd = pmd_offset(pgd, taddr);
+	pte = pte_offset(pmd, taddr);
+	return pte;
+}
+
+#define mk_pte_huge(entry) { pte_val(entry) |= _PAGE_P; }
+
+static void
+set_huge_pte (struct mm_struct *mm, struct vm_area_struct *vma,
+	      struct page *page, pte_t * page_table, int write_access)
+{
+	pte_t entry;
+
+	mm->rss += (HPAGE_SIZE / PAGE_SIZE);
+	if (write_access) {
+		entry =
+		    pte_mkwrite(pte_mkdirty(mk_pte(page, vma->vm_page_prot)));
+	} else
+		entry = pte_wrprotect(mk_pte(page, vma->vm_page_prot));
+	entry = pte_mkyoung(entry);
+	mk_pte_huge(entry);
+	set_pte(page_table, entry);
+	return;
+}
+/*
+ * This function checks for proper alignment of input addr and len parameters.
+ */
+int is_aligned_hugepage_range(unsigned long addr, unsigned long len)
+{
+	if (len & ~HPAGE_MASK)
+		return -EINVAL;
+	if (addr & ~HPAGE_MASK)
+		return -EINVAL;
+	if (REGION_NUMBER(addr) != REGION_HPAGE)
+		return -EINVAL;
+
+	return 0;
+}
+/* This function checks if the address and address+len falls out of HugeTLB region.  It
+ * return -EINVAL if any part of address range falls in HugeTLB region.
+ */
+int  is_invalid_hugepage_range(unsigned long addr, unsigned long len)
+{
+	if (REGION_NUMBER(addr) == REGION_HPAGE)
+		return -EINVAL;
+	if (REGION_NUMBER(addr+len) == REGION_HPAGE)
+		return -EINVAL;
+	return 0;
+}
+
+/*
+ * Same as generic free_pgtables(), except constant PGDIR_* and pgd_offset
+ * are hugetlb region specific.
+ */
+void hugetlb_free_pgtables(struct mm_struct * mm, struct vm_area_struct *prev,
+	unsigned long start, unsigned long end)
+{
+	unsigned long first = start & HUGETLB_PGDIR_MASK;
+	unsigned long last = end + HUGETLB_PGDIR_SIZE - 1;
+	unsigned long start_index, end_index;
+
+	if (!prev) {
+		prev = mm->mmap;
+		if (!prev)
+			goto no_mmaps;
+		if (prev->vm_end > start) {
+			if (last > prev->vm_start)
+				last = prev->vm_start;
+			goto no_mmaps;
+		}
+	}
+	for (;;) {
+		struct vm_area_struct *next = prev->vm_next;
+
+		if (next) {
+			if (next->vm_start < start) {
+				prev = next;
+				continue;
+			}
+			if (last > next->vm_start)
+				last = next->vm_start;
+		}
+		if (prev->vm_end > first)
+			first = prev->vm_end + HUGETLB_PGDIR_SIZE - 1;
+		break;
+	}
+no_mmaps:
+	if (last < first)
+		return;
+	/*
+	 * If the PGD bits are not consecutive in the virtual address, the
+	 * old method of shifting the VA >> by PGDIR_SHIFT doesn't work.
+	 */
+	start_index = pgd_index(htlbpage_to_page(first));
+	end_index = pgd_index(htlbpage_to_page(last));
+	if (end_index > start_index) {
+		clear_page_tables(mm, start_index, end_index - start_index);
+		flush_tlb_pgtables(mm, first & HUGETLB_PGDIR_MASK,
+				   last & HUGETLB_PGDIR_MASK);
+	}
+}
+
+int copy_hugetlb_page_range(struct mm_struct *dst, struct mm_struct *src,
+			struct vm_area_struct *vma)
+{
+	pte_t *src_pte, *dst_pte, entry;
+	struct page *ptepage;
+	unsigned long addr = vma->vm_start;
+	unsigned long end = vma->vm_end;
+
+	while (addr < end) {
+		dst_pte = huge_pte_alloc(dst, addr);
+		if (!dst_pte)
+			goto nomem;
+		src_pte = huge_pte_offset(src, addr);
+		entry = *src_pte;
+		ptepage = pte_page(entry);
+		get_page(ptepage);
+		set_pte(dst_pte, entry);
+		dst->rss += (HPAGE_SIZE / PAGE_SIZE);
+		addr += HPAGE_SIZE;
+	}
+	return 0;
+nomem:
+	return -ENOMEM;
+}
+
+int
+follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma,
+		    struct page **pages, struct vm_area_struct **vmas,
+		    unsigned long *st, int *length, int i)
+{
+	pte_t *ptep, pte;
+	unsigned long start = *st;
+	unsigned long pstart;
+	int len = *length;
+	struct page *page;
+
+	do {
+		pstart = start;
+		ptep = huge_pte_offset(mm, start);
+		pte = *ptep;
+
+back1:
+		page = pte_page(pte);
+		if (pages) {
+			page += ((start & ~HPAGE_MASK) >> PAGE_SHIFT);
+			pages[i] = page;
+		}
+		if (vmas)
+			vmas[i] = vma;
+		i++;
+		len--;
+		start += PAGE_SIZE;
+		if (((start & HPAGE_MASK) == pstart) && len &&
+				(start < vma->vm_end))
+			goto back1;
+	} while (len && start < vma->vm_end);
+	*length = len;
+	*st = start;
+	return i;
+}
+
+void free_huge_page(struct page *page)
+{
+	BUG_ON(page_count(page));
+	BUG_ON(page->mapping);
+
+	INIT_LIST_HEAD(&page->list);
+
+	spin_lock(&htlbpage_lock);
+	list_add(&page->list, &htlbpage_freelist);
+	htlbpagemem++;
+	spin_unlock(&htlbpage_lock);
+}
+
+void huge_page_release(struct page *page)
+{
+	if (!put_page_testzero(page))
+		return;
+
+	free_huge_page(page);
+}
+
+void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, unsigned long end)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	unsigned long address;
+	pte_t *pte;
+	struct page *page;
+
+	BUG_ON(start & (HPAGE_SIZE - 1));
+	BUG_ON(end & (HPAGE_SIZE - 1));
+
+	for (address = start; address < end; address += HPAGE_SIZE) {
+		pte = huge_pte_offset(mm, address);
+		if (pte_none(*pte))
+			continue;
+		page = pte_page(*pte);
+		huge_page_release(page);
+		pte_clear(pte);
+	}
+	mm->rss -= (end - start) >> PAGE_SHIFT;
+	flush_tlb_range(mm, start, end);
+}
+
+void zap_hugepage_range(struct vm_area_struct *vma, unsigned long start, unsigned long length)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	spin_lock(&mm->page_table_lock);
+	unmap_hugepage_range(vma, start, start + length);
+	spin_unlock(&mm->page_table_lock);
+}
+
+int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
+{
+	struct mm_struct *mm = current->mm;
+	struct inode *inode = mapping->host;
+	unsigned long addr;
+	int ret = 0;
+
+	BUG_ON(vma->vm_start & ~HPAGE_MASK);
+	BUG_ON(vma->vm_end & ~HPAGE_MASK);
+
+	spin_lock(&mm->page_table_lock);
+	for (addr = vma->vm_start; addr < vma->vm_end; addr += HPAGE_SIZE) {
+		unsigned long idx;
+		pte_t *pte = huge_pte_alloc(mm, addr);
+		struct page *page;
+
+		if (!pte) {
+			ret = -ENOMEM;
+			goto out;
+		}
+		if (!pte_none(*pte))
+			continue;
+
+		idx = ((addr - vma->vm_start) >> HPAGE_SHIFT)
+			+ (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT));
+		page = find_get_page(mapping, idx);
+		if (!page) {
+			/* charge the fs quota first */
+			if (hugetlb_get_quota(mapping)) {
+				ret = -ENOMEM;
+				goto out;
+			}
+			page = alloc_hugetlb_page();
+			if (!page) {
+				hugetlb_put_quota(mapping);
+				ret = -ENOMEM;
+				goto out;
+			}
+			add_to_page_cache(page, mapping, idx);
+			unlock_page(page);
+		}
+		set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE);
+	}
+out:
+	spin_unlock(&mm->page_table_lock);
+	return ret;
+}
+
+unsigned long hugetlb_get_unmapped_area(struct file *file, unsigned long addr, unsigned long len,
+		unsigned long pgoff, unsigned long flags)
+{
+	struct vm_area_struct *vmm;
+
+	if (len > RGN_MAP_LIMIT)
+		return -ENOMEM;
+	if (len & ~HPAGE_MASK)
+		return -EINVAL;
+	/* This code assumes that REGION_HPAGE != 0. */
+	if ((REGION_NUMBER(addr) != REGION_HPAGE) || (addr & (HPAGE_SIZE - 1)))
+		addr = TASK_HPAGE_BASE;
+	else
+		addr = COLOR_HALIGN(addr);
+	for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
+		/* At this point:  (!vmm || addr < vmm->vm_end). */
+		if (REGION_OFFSET(addr) + len > RGN_MAP_LIMIT)
+			return -ENOMEM;
+		if (!vmm || (addr + len) <= vmm->vm_start)
+			return addr;
+		addr = COLOR_HALIGN(vmm->vm_end);
+	}
+}
+void update_and_free_page(struct page *page)
+{
+	int j;
+	struct page *map;
+
+	map = page;
+	htlbzone_pages--;
+	for (j = 0; j < (HPAGE_SIZE / PAGE_SIZE); j++) {
+		map->flags &= ~(1 << PG_locked | 1 << PG_error | 1 << PG_referenced |
+				1 << PG_dirty | 1 << PG_active | 1 << PG_reserved);
+		set_page_count(map, 0);
+		map++;
+	}
+	set_page_count(page, 1);
+	__free_pages(page, HUGETLB_PAGE_ORDER);
+}
+
+int try_to_free_low(int count)
+{
+	struct list_head *p;
+	struct page *page, *map;
+
+	map = NULL;
+	spin_lock(&htlbpage_lock);
+	list_for_each(p, &htlbpage_freelist) {
+		if (map) {
+			list_del(&map->list);
+			update_and_free_page(map);
+			htlbpagemem--;
+			map = NULL;
+			if (++count == 0)
+				break;
+		}
+		page = list_entry(p, struct page, list);
+		if ((page_zone(page))->name[0] != 'H') //Look for non-Highmem zones.
+			map = page;
+	}
+	if (map) {
+		list_del(&map->list);
+		update_and_free_page(map);
+		htlbpagemem--;
+		count++;
+	}
+	spin_unlock(&htlbpage_lock);
+	return count;
+}
+
+int set_hugetlb_mem_size(int count)
+{
+	int j, lcount;
+	struct page *page, *map;
+
+	if (count < 0)
+		lcount = count;
+	else
+		lcount = count - htlbzone_pages;
+
+	if (lcount == 0)
+		return (int)htlbzone_pages;
+	if (lcount > 0) {	/* Increase the mem size. */
+		while (lcount--) {
+			page = alloc_pages(__GFP_HIGHMEM, HUGETLB_PAGE_ORDER);
+			if (page == NULL)
+				break;
+			map = page;
+			for (j = 0; j < (HPAGE_SIZE / PAGE_SIZE); j++) {
+				SetPageReserved(map);
+				map++;
+			}
+			spin_lock(&htlbpage_lock);
+			list_add(&page->list, &htlbpage_freelist);
+			htlbpagemem++;
+			htlbzone_pages++;
+			spin_unlock(&htlbpage_lock);
+		}
+		return (int) htlbzone_pages;
+	}
+	/* Shrink the memory size. */
+	lcount = try_to_free_low(lcount);
+	while (lcount++ < 0) {
+		page = alloc_hugetlb_page();
+		if (page == NULL)
+			break;
+		spin_lock(&htlbpage_lock);
+		update_and_free_page(page);
+		spin_unlock(&htlbpage_lock);
+	}
+	return (int) htlbzone_pages;
+}
+
+int hugetlb_sysctl_handler(ctl_table *table, int write, struct file *file, void *buffer, size_t *length)
+{
+	proc_dointvec(table, write, file, buffer, length);
+	htlbpage_max = set_hugetlb_mem_size(htlbpage_max);
+	return 0;
+}
+
+static int __init hugetlb_setup(char *s)
+{
+	if (sscanf(s, "%d", &htlbpage_max) <= 0)
+		htlbpage_max = 0;
+	return 1;
+}
+__setup("hugepages=", hugetlb_setup);
+
+static int __init hugetlb_init(void)
+{
+	int i, j;
+	struct page *page;
+
+	for (i = 0; i < htlbpage_max; ++i) {
+		page = alloc_pages(__GFP_HIGHMEM, HUGETLB_PAGE_ORDER);
+		if (!page)
+			break;
+		for (j = 0; j < HPAGE_SIZE/PAGE_SIZE; ++j)
+			SetPageReserved(&page[j]);
+		spin_lock(&htlbpage_lock);
+		list_add(&page->list, &htlbpage_freelist);
+		spin_unlock(&htlbpage_lock);
+	}
+	htlbpage_max = htlbpagemem = htlbzone_pages = i;
+	printk("Total HugeTLB memory allocated, %ld\n", htlbpagemem);
+	return 0;
+}
+module_init(hugetlb_init);
+
+int hugetlb_report_meminfo(char *buf)
+{
+	return sprintf(buf,
+			"HugePages_Total: %5lu\n"
+			"HugePages_Free:  %5lu\n"
+			"Hugepagesize:    %5lu kB\n",
+			htlbzone_pages,
+			htlbpagemem,
+			HPAGE_SIZE/1024);
+}
+
+int is_hugepage_mem_enough(size_t size)
+{
+	if (size > (htlbpagemem << HPAGE_SHIFT))
+		return 0;
+	return 1;
+}
+
+static struct page *hugetlb_nopage(struct vm_area_struct * area, unsigned long address, int unused)
+{
+	BUG();
+	return NULL;
+}
+
+struct vm_operations_struct hugetlb_vm_ops = {
+	.nopage =	hugetlb_nopage,
+};