arch/ia64/mm/hugetlbpage.c - pub/scm/linux/kernel/git/jes/linux - Git at Google

 /*
  * IA-64 Huge TLB Page Support for Kernel.
  *
  * Copyright (C) 2002-2004 Rohit Seth <rohit.seth@intel.com>
  * Copyright (C) 2003-2004 Ken Chen <kenneth.w.chen@intel.com>
  *
  * Sep, 2003: add numa support
  * Feb, 2004: dynamic hugetlb page size via boot parameter
  */

 #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>
 #include <asm/tlbflush.h>

 unsigned int hpage_shift=HPAGE_SHIFT_DEFAULT;

 static pte_t *
 huge_pte_alloc (struct mm_struct *mm, unsigned long addr)
 {
 	unsigned long taddr = htlbpage_to_page(addr);
 	pgd_t *pgd;
 	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte = NULL;

 	pgd = pgd_offset(mm, taddr);
 	pud = pud_alloc(mm, pgd, taddr);
 	if (pud) {
 		pmd = pmd_alloc(mm, pud, taddr);
 		if (pmd)
 			pte = pte_alloc_map(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;
 	pud_t *pud;
 	pmd_t *pmd;
 	pte_t *pte = NULL;

 	pgd = pgd_offset(mm, taddr);
 	if (pgd_present(*pgd)) {
 		pud = pud_offset(pgd, taddr);
 		if (pud_present(*pud)) {
 			pmd = pmd_offset(pud, taddr);
 			if (pmd_present(*pmd))
 				pte = pte_offset_map(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;

 	add_mm_counter(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;
 }

 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);
 		add_mm_counter(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 & HPAGE_MASK;
 		ptep = huge_pte_offset(mm, start);
 		pte = *ptep;

 back1:
 		page = pte_page(pte);
 		if (pages) {
 			page += ((start & ~HPAGE_MASK) >> PAGE_SHIFT);
 			get_page(page);
 			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;
 }

 struct page *follow_huge_addr(struct mm_struct *mm, unsigned long addr, int write)
 {
 	struct page *page;
 	pte_t *ptep;

 	if (REGION_NUMBER(addr) != REGION_HPAGE)
 		return ERR_PTR(-EINVAL);

 	ptep = huge_pte_offset(mm, addr);
 	if (!ptep || pte_none(*ptep))
 		return NULL;
 	page = pte_page(*ptep);
 	page += ((addr & ~HPAGE_MASK) >> PAGE_SHIFT);
 	return page;
 }
 int pmd_huge(pmd_t pmd)
 {
 	return 0;
 }
 struct page *
 follow_huge_pmd(struct mm_struct *mm, unsigned long address, pmd_t *pmd, int write)
 {
 	return NULL;
 }

 /*
  * Same as generic free_pgtables(), except constant PGDIR_* and pgd_offset
  * are hugetlb region specific.
  */
 void hugetlb_free_pgtables(struct mmu_gather *tlb, 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;
 	struct mm_struct *mm = tlb->mm;

 	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;
 		break;
 	}
 no_mmaps:
 	if (last < first)	/* for arches with discontiguous pgd indices */
 		return;
 	clear_page_range(tlb, first, last);
 }

 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);
 		put_page(page);
 		pte_clear(mm, address, pte);
 	}
 	add_mm_counter(mm, rss, - ((end - start) >> PAGE_SHIFT));
 	flush_tlb_range(vma, start, end);
 }

 int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
 {
 	struct mm_struct *mm = current->mm;
 	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_huge_page();
 			if (!page) {
 				hugetlb_put_quota(mapping);
 				ret = -ENOMEM;
 				goto out;
 			}
 			ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
 			if (! ret) {
 				unlock_page(page);
 			} else {
 				hugetlb_put_quota(mapping);
 				page_cache_release(page);
 				goto out;
 			}
 		}
 		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 = HPAGE_REGION_BASE;
 	else
 		addr = ALIGN(addr, HPAGE_SIZE);
 	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 = ALIGN(vmm->vm_end, HPAGE_SIZE);
 	}
 }

 static int __init hugetlb_setup_sz(char *str)
 {
 	u64 tr_pages;
 	unsigned long long size;

 	if (ia64_pal_vm_page_size(&tr_pages, NULL) != 0)
 		/*
 		 * shouldn't happen, but just in case.
 		 */
 		tr_pages = 0x15557000UL;

 	size = memparse(str, &str);
 	if (*str || (size & (size-1)) || !(tr_pages & size) ||
 		size <= PAGE_SIZE ||
 		size >= (1UL << PAGE_SHIFT << MAX_ORDER)) {
 		printk(KERN_WARNING "Invalid huge page size specified\n");
 		return 1;
 	}

 	hpage_shift = __ffs(size);
 	/*
 	 * boot cpu already executed ia64_mmu_init, and has HPAGE_SHIFT_DEFAULT
 	 * override here with new page shift.
 	 */
 	ia64_set_rr(HPAGE_REGION_BASE, hpage_shift << 2);
 	return 1;
 }
 __setup("hugepagesz=", hugetlb_setup_sz);
	/*
	* IA-64 Huge TLB Page Support for Kernel.
	*
	* Copyright (C) 2002-2004 Rohit Seth <rohit.seth@intel.com>
	* Copyright (C) 2003-2004 Ken Chen <kenneth.w.chen@intel.com>
	*
	* Sep, 2003: add numa support
	* Feb, 2004: dynamic hugetlb page size via boot parameter
	*/

	#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>
	#include <asm/tlbflush.h>

	unsigned int hpage_shift=HPAGE_SHIFT_DEFAULT;

	static pte_t *
	huge_pte_alloc (struct mm_struct *mm, unsigned long addr)
	{
	unsigned long taddr = htlbpage_to_page(addr);
	pgd_t *pgd;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte = NULL;

	pgd = pgd_offset(mm, taddr);
	pud = pud_alloc(mm, pgd, taddr);
	if (pud) {
	pmd = pmd_alloc(mm, pud, taddr);
	if (pmd)
	pte = pte_alloc_map(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;
	pud_t *pud;
	pmd_t *pmd;
	pte_t *pte = NULL;

	pgd = pgd_offset(mm, taddr);
	if (pgd_present(*pgd)) {
	pud = pud_offset(pgd, taddr);
	if (pud_present(*pud)) {
	pmd = pmd_offset(pud, taddr);
	if (pmd_present(*pmd))
	pte = pte_offset_map(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;

	add_mm_counter(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;
	}

	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);
	add_mm_counter(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 & HPAGE_MASK;
	ptep = huge_pte_offset(mm, start);
	pte = *ptep;

	back1:
	page = pte_page(pte);
	if (pages) {
	page += ((start & ~HPAGE_MASK) >> PAGE_SHIFT);
	get_page(page);
	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;
	}

	struct page follow_huge_addr(struct mm_struct mm, unsigned long addr, int write)
	{
	struct page *page;
	pte_t *ptep;

	if (REGION_NUMBER(addr) != REGION_HPAGE)
	return ERR_PTR(-EINVAL);

	ptep = huge_pte_offset(mm, addr);
	if (!ptep \|\| pte_none(*ptep))
	return NULL;
	page = pte_page(*ptep);
	page += ((addr & ~HPAGE_MASK) >> PAGE_SHIFT);
	return page;
	}
	int pmd_huge(pmd_t pmd)
	{
	return 0;
	}
	struct page *
	follow_huge_pmd(struct mm_struct mm, unsigned long address, pmd_t pmd, int write)
	{
	return NULL;
	}

	/*
	* Same as generic free_pgtables(), except constant PGDIR_* and pgd_offset
	* are hugetlb region specific.
	*/
	void hugetlb_free_pgtables(struct mmu_gather tlb, 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;
	struct mm_struct *mm = tlb->mm;

	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;
	break;
	}
	no_mmaps:
	if (last < first) /* for arches with discontiguous pgd indices */
	return;
	clear_page_range(tlb, first, last);
	}

	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);
	put_page(page);
	pte_clear(mm, address, pte);
	}
	add_mm_counter(mm, rss, - ((end - start) >> PAGE_SHIFT));
	flush_tlb_range(vma, start, end);
	}

	int hugetlb_prefault(struct address_space mapping, struct vm_area_struct vma)
	{
	struct mm_struct *mm = current->mm;
	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_huge_page();
	if (!page) {
	hugetlb_put_quota(mapping);
	ret = -ENOMEM;
	goto out;
	}
	ret = add_to_page_cache(page, mapping, idx, GFP_ATOMIC);
	if (! ret) {
	unlock_page(page);
	} else {
	hugetlb_put_quota(mapping);
	page_cache_release(page);
	goto out;
	}
	}
	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 = HPAGE_REGION_BASE;
	else
	addr = ALIGN(addr, HPAGE_SIZE);
	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 = ALIGN(vmm->vm_end, HPAGE_SIZE);
	}
	}

	static int __init hugetlb_setup_sz(char *str)
	{
	u64 tr_pages;
	unsigned long long size;

	if (ia64_pal_vm_page_size(&tr_pages, NULL) != 0)
	/*
	* shouldn't happen, but just in case.
	*/
	tr_pages = 0x15557000UL;

	size = memparse(str, &str);
	if (*str \|\| (size & (size-1)) \|\| !(tr_pages & size) \|\|
	size <= PAGE_SIZE \|\|
	size >= (1UL << PAGE_SHIFT << MAX_ORDER)) {
	printk(KERN_WARNING "Invalid huge page size specified\n");
	return 1;
	}

	hpage_shift = __ffs(size);
	/*
	* boot cpu already executed ia64_mmu_init, and has HPAGE_SHIFT_DEFAULT
	* override here with new page shift.
	*/
	ia64_set_rr(HPAGE_REGION_BASE, hpage_shift << 2);
	return 1;
	}
	__setup("hugepagesz=", hugetlb_setup_sz);