X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=arch%2Fi386%2Fmm%2Fhugetlbpage.c;h=a7d8915854116264048f62c84d63dc495fc212b7;hb=43bc926fffd92024b46cafaf7350d669ba9ca884;hp=a0eab6715cbd2e8bd748eea8085defbb4d7edd57;hpb=9bf4aaab3e101692164d49b7ca357651eb691cb6;p=linux-2.6.git

diff --git a/arch/i386/mm/hugetlbpage.c b/arch/i386/mm/hugetlbpage.c
index a0eab6715..a7d891585 100644
--- a/arch/i386/mm/hugetlbpage.c
+++ b/arch/i386/mm/hugetlbpage.c
@@ -18,124 +18,34 @@
 #include <asm/tlb.h>
 #include <asm/tlbflush.h>
 
-static pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_alloc(struct mm_struct *mm, unsigned long addr)
 {
 	pgd_t *pgd;
-	pmd_t *pmd = NULL;
+	pud_t *pud;
+	pte_t *pte = NULL;
 
 	pgd = pgd_offset(mm, addr);
-	pmd = pmd_alloc(mm, pgd, addr);
-	return (pte_t *) pmd;
+	pud = pud_alloc(mm, pgd, addr);
+	if (pud)
+		pte = (pte_t *) pmd_alloc(mm, pud, addr);
+	BUG_ON(pte && !pte_none(*pte) && !pte_huge(*pte));
+
+	return pte;
 }
 
-static pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
+pte_t *huge_pte_offset(struct mm_struct *mm, unsigned long addr)
 {
 	pgd_t *pgd;
+	pud_t *pud;
 	pmd_t *pmd = NULL;
 
 	pgd = pgd_offset(mm, addr);
-	pmd = pmd_offset(pgd, addr);
-	return (pte_t *) pmd;
-}
-
-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);
-	vx_rsspages_add(mm, 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);
-}
-
-/*
- * 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;
-	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);
-		// dst->rss += (HPAGE_SIZE / PAGE_SIZE);
-		vx_rsspages_add(dst, 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 *position, int *length, int i)
-{
-	unsigned long vpfn, vaddr = *position;
-	int remainder = *length;
-
-	WARN_ON(!is_vm_hugetlb_page(vma));
-
-	vpfn = vaddr/PAGE_SIZE;
-	while (vaddr < vma->vm_end && remainder) {
-
-		if (pages) {
-			pte_t *pte;
-			struct page *page;
-
-			pte = huge_pte_offset(mm, vaddr);
-
-			/* hugetlb should be locked, and hence, prefaulted */
-			WARN_ON(!pte || pte_none(*pte));
-
-			page = &pte_page(*pte)[vpfn % (HPAGE_SIZE/PAGE_SIZE)];
-
-			WARN_ON(!PageCompound(page));
-
-			get_page(page);
-			pages[i] = page;
-		}
-
-		if (vmas)
-			vmas[i] = vma;
-
-		vaddr += PAGE_SIZE;
-		++vpfn;
-		--remainder;
-		++i;
+	if (pgd_present(*pgd)) {
+		pud = pud_offset(pgd, addr);
+		if (pud_present(*pud))
+			pmd = pmd_offset(pud, addr);
 	}
-
-	*length = remainder;
-	*position = vaddr;
-
-	return i;
+	return (pte_t *) pmd;
 }
 
 #if 0	/* This is just for testing */
@@ -202,85 +112,166 @@ follow_huge_pmd(struct mm_struct *mm, unsigned long address,
 }
 #endif
 
-void unmap_hugepage_range(struct vm_area_struct *vma,
-		unsigned long start, unsigned long end)
+/* x86_64 also uses this file */
+
+#ifdef HAVE_ARCH_HUGETLB_UNMAPPED_AREA
+static unsigned long hugetlb_get_unmapped_area_bottomup(struct file *file,
+		unsigned long addr, unsigned long len,
+		unsigned long pgoff, unsigned long flags)
 {
-	struct mm_struct *mm = vma->vm_mm;
-	unsigned long address;
-	pte_t pte;
-	struct page *page;
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
+	unsigned long start_addr;
 
-	BUG_ON(start & (HPAGE_SIZE - 1));
-	BUG_ON(end & (HPAGE_SIZE - 1));
+	if (len > mm->cached_hole_size) {
+	        start_addr = mm->free_area_cache;
+	} else {
+	        start_addr = TASK_UNMAPPED_BASE;
+	        mm->cached_hole_size = 0;
+	}
 
-	for (address = start; address < end; address += HPAGE_SIZE) {
-		pte = ptep_get_and_clear(huge_pte_offset(mm, address));
-		if (pte_none(pte))
-			continue;
-		page = pte_page(pte);
-		put_page(page);
+full_search:
+	addr = ALIGN(start_addr, HPAGE_SIZE);
+
+	for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
+		/* At this point:  (!vma || addr < vma->vm_end). */
+		if (TASK_SIZE - len < addr) {
+			/*
+			 * Start a new search - just in case we missed
+			 * some holes.
+			 */
+			if (start_addr != TASK_UNMAPPED_BASE) {
+				start_addr = TASK_UNMAPPED_BASE;
+				mm->cached_hole_size = 0;
+				goto full_search;
+			}
+			return -ENOMEM;
+		}
+		if (!vma || addr + len <= vma->vm_start) {
+			mm->free_area_cache = addr + len;
+			return addr;
+		}
+		if (addr + mm->cached_hole_size < vma->vm_start)
+		        mm->cached_hole_size = vma->vm_start - addr;
+		addr = ALIGN(vma->vm_end, HPAGE_SIZE);
 	}
-	// mm->rss -= (end - start) >> PAGE_SHIFT;
-	vx_rsspages_sub(mm, (end - start) >> PAGE_SHIFT);
-	flush_tlb_range(vma, start, end);
 }
 
-int hugetlb_prefault(struct address_space *mapping, struct vm_area_struct *vma)
+static unsigned long hugetlb_get_unmapped_area_topdown(struct file *file,
+		unsigned long addr0, unsigned long len,
+		unsigned long pgoff, unsigned long flags)
 {
 	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;
+	struct vm_area_struct *vma, *prev_vma;
+	unsigned long base = mm->mmap_base, addr = addr0;
+	unsigned long largest_hole = mm->cached_hole_size;
+	int first_time = 1;
+
+	/* don't allow allocations above current base */
+	if (mm->free_area_cache > base)
+		mm->free_area_cache = base;
+
+	if (len <= largest_hole) {
+	        largest_hole = 0;
+		mm->free_area_cache  = base;
+	}
+try_again:
+	/* make sure it can fit in the remaining address space */
+	if (mm->free_area_cache < len)
+		goto fail;
+
+	/* either no address requested or cant fit in requested address hole */
+	addr = (mm->free_area_cache - len) & HPAGE_MASK;
+	do {
+		/*
+		 * Lookup failure means no vma is above this address,
+		 * i.e. return with success:
+		 */
+		if (!(vma = find_vma_prev(mm, addr, &prev_vma)))
+			return addr;
+
+		/*
+		 * new region fits between prev_vma->vm_end and
+		 * vma->vm_start, use it:
+		 */
+		if (addr + len <= vma->vm_start &&
+		            (!prev_vma || (addr >= prev_vma->vm_end))) {
+			/* remember the address as a hint for next time */
+		        mm->cached_hole_size = largest_hole;
+		        return (mm->free_area_cache = addr);
+		} else {
+			/* pull free_area_cache down to the first hole */
+		        if (mm->free_area_cache == vma->vm_end) {
+				mm->free_area_cache = vma->vm_start;
+				mm->cached_hole_size = largest_hole;
+			}
 		}
 
-		if (!pte_none(*pte)) {
-			pmd_t *pmd = (pmd_t *) pte;
+		/* remember the largest hole we saw so far */
+		if (addr + largest_hole < vma->vm_start)
+		        largest_hole = vma->vm_start - addr;
+
+		/* try just below the current vma->vm_start */
+		addr = (vma->vm_start - len) & HPAGE_MASK;
+	} while (len <= vma->vm_start);
+
+fail:
+	/*
+	 * if hint left us with no space for the requested
+	 * mapping then try again:
+	 */
+	if (first_time) {
+		mm->free_area_cache = base;
+		largest_hole = 0;
+		first_time = 0;
+		goto try_again;
+	}
+	/*
+	 * A failed mmap() very likely causes application failure,
+	 * so fall back to the bottom-up function here. This scenario
+	 * can happen with large stack limits and large mmap()
+	 * allocations.
+	 */
+	mm->free_area_cache = TASK_UNMAPPED_BASE;
+	mm->cached_hole_size = ~0UL;
+	addr = hugetlb_get_unmapped_area_bottomup(file, addr0,
+			len, pgoff, flags);
+
+	/*
+	 * Restore the topdown base:
+	 */
+	mm->free_area_cache = base;
+	mm->cached_hole_size = ~0UL;
+
+	return addr;
+}
 
-			page = pmd_page(*pmd);
-			pmd_clear(pmd);
-			dec_page_state(nr_page_table_pages);
-			page_cache_release(page);
-		}
+unsigned long
+hugetlb_get_unmapped_area(struct file *file, unsigned long addr,
+		unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+	struct mm_struct *mm = current->mm;
+	struct vm_area_struct *vma;
 
-		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);
-				free_huge_page(page);
-				goto out;
-			}
-		}
-		set_huge_pte(mm, vma, page, pte, vma->vm_flags & VM_WRITE);
+	if (len & ~HPAGE_MASK)
+		return -EINVAL;
+	if (len > TASK_SIZE)
+		return -ENOMEM;
+
+	if (addr) {
+		addr = ALIGN(addr, HPAGE_SIZE);
+		vma = find_vma(mm, addr);
+		if (TASK_SIZE - len >= addr &&
+		    (!vma || addr + len <= vma->vm_start))
+			return addr;
 	}
-out:
-	spin_unlock(&mm->page_table_lock);
-	return ret;
+	if (mm->get_unmapped_area == arch_get_unmapped_area)
+		return hugetlb_get_unmapped_area_bottomup(file, addr, len,
+				pgoff, flags);
+	else
+		return hugetlb_get_unmapped_area_topdown(file, addr, len,
+				pgoff, flags);
 }
+
+#endif /*HAVE_ARCH_HUGETLB_UNMAPPED_AREA*/
+