diff options
Diffstat (limited to 'mm/hugetlb.c')
| -rw-r--r-- | mm/hugetlb.c | 67 |
1 files changed, 47 insertions, 20 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index 67a71191136e..ce8cbb29860b 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -262,7 +262,7 @@ struct resv_map { struct list_head regions; }; -struct resv_map *resv_map_alloc(void) +static struct resv_map *resv_map_alloc(void) { struct resv_map *resv_map = kmalloc(sizeof(*resv_map), GFP_KERNEL); if (!resv_map) @@ -274,7 +274,7 @@ struct resv_map *resv_map_alloc(void) return resv_map; } -void resv_map_release(struct kref *ref) +static void resv_map_release(struct kref *ref) { struct resv_map *resv_map = container_of(ref, struct resv_map, refs); @@ -289,7 +289,7 @@ static struct resv_map *vma_resv_map(struct vm_area_struct *vma) if (!(vma->vm_flags & VM_SHARED)) return (struct resv_map *)(get_vma_private_data(vma) & ~HPAGE_RESV_MASK); - return 0; + return NULL; } static void set_vma_resv_map(struct vm_area_struct *vma, struct resv_map *map) @@ -1459,11 +1459,11 @@ int hugetlb_report_meminfo(char *buf) { struct hstate *h = &default_hstate; return sprintf(buf, - "HugePages_Total: %5lu\n" - "HugePages_Free: %5lu\n" - "HugePages_Rsvd: %5lu\n" - "HugePages_Surp: %5lu\n" - "Hugepagesize: %5lu kB\n", + "HugePages_Total: %5lu\n" + "HugePages_Free: %5lu\n" + "HugePages_Rsvd: %5lu\n" + "HugePages_Surp: %5lu\n" + "Hugepagesize: %8lu kB\n", h->nr_huge_pages, h->free_huge_pages, h->resv_huge_pages, @@ -1747,10 +1747,8 @@ void unmap_hugepage_range(struct vm_area_struct *vma, unsigned long start, * from other VMAs and let the children be SIGKILLed if they are faulting the * same region. */ -int unmap_ref_private(struct mm_struct *mm, - struct vm_area_struct *vma, - struct page *page, - unsigned long address) +static int unmap_ref_private(struct mm_struct *mm, struct vm_area_struct *vma, + struct page *page, unsigned long address) { struct vm_area_struct *iter_vma; struct address_space *mapping; @@ -2008,7 +2006,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, entry = huge_ptep_get(ptep); if (huge_pte_none(entry)) { ret = hugetlb_no_page(mm, vma, address, ptep, write_access); - goto out_unlock; + goto out_mutex; } ret = 0; @@ -2024,7 +2022,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, if (write_access && !pte_write(entry)) { if (vma_needs_reservation(h, vma, address) < 0) { ret = VM_FAULT_OOM; - goto out_unlock; + goto out_mutex; } if (!(vma->vm_flags & VM_SHARED)) @@ -2034,10 +2032,23 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, spin_lock(&mm->page_table_lock); /* Check for a racing update before calling hugetlb_cow */ - if (likely(pte_same(entry, huge_ptep_get(ptep)))) - if (write_access && !pte_write(entry)) + if (unlikely(!pte_same(entry, huge_ptep_get(ptep)))) + goto out_page_table_lock; + + + if (write_access) { + if (!pte_write(entry)) { ret = hugetlb_cow(mm, vma, address, ptep, entry, pagecache_page); + goto out_page_table_lock; + } + entry = pte_mkdirty(entry); + } + entry = pte_mkyoung(entry); + if (huge_ptep_set_access_flags(vma, address, ptep, entry, write_access)) + update_mmu_cache(vma, address, entry); + +out_page_table_lock: spin_unlock(&mm->page_table_lock); if (pagecache_page) { @@ -2045,7 +2056,7 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, put_page(pagecache_page); } -out_unlock: +out_mutex: mutex_unlock(&hugetlb_instantiation_mutex); return ret; @@ -2060,6 +2071,14 @@ follow_huge_pud(struct mm_struct *mm, unsigned long address, return NULL; } +static int huge_zeropage_ok(pte_t *ptep, int write, int shared) +{ + if (!ptep || write || shared) + return 0; + else + return huge_pte_none(huge_ptep_get(ptep)); +} + 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, @@ -2069,6 +2088,8 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, unsigned long vaddr = *position; int remainder = *length; struct hstate *h = hstate_vma(vma); + int zeropage_ok = 0; + int shared = vma->vm_flags & VM_SHARED; spin_lock(&mm->page_table_lock); while (vaddr < vma->vm_end && remainder) { @@ -2081,8 +2102,11 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, * first, for the page indexing below to work. */ pte = huge_pte_offset(mm, vaddr & huge_page_mask(h)); + if (huge_zeropage_ok(pte, write, shared)) + zeropage_ok = 1; - if (!pte || huge_pte_none(huge_ptep_get(pte)) || + if (!pte || + (huge_pte_none(huge_ptep_get(pte)) && !zeropage_ok) || (write && !pte_write(huge_ptep_get(pte)))) { int ret; @@ -2102,8 +2126,11 @@ int follow_hugetlb_page(struct mm_struct *mm, struct vm_area_struct *vma, page = pte_page(huge_ptep_get(pte)); same_page: if (pages) { - get_page(page); - pages[i] = page + pfn_offset; + if (zeropage_ok) + pages[i] = ZERO_PAGE(0); + else + pages[i] = page + pfn_offset; + get_page(pages[i]); } if (vmas) |