diff options
| author | Adam Litke <agl@us.ibm.com> | 2006-01-06 11:10:43 +0300 |
|---|---|---|
| committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-01-06 19:33:22 +0300 |
| commit | 86e5216f8d8aa258ba836caffe2613d79cc9aead (patch) | |
| tree | 33669c0194490700b575fceb0e5e010a4468a5fe | |
| parent | 85ef47f74afe96c8c23eaa605f28cc01443c905f (diff) | |
| download | linux-86e5216f8d8aa258ba836caffe2613d79cc9aead.tar.xz | |
[PATCH] Hugetlb: Reorganize hugetlb_fault to prepare for COW
This patch splits the "no_page()" type activity into its own function,
hugetlb_no_page(). hugetlb_fault() becomes the entry point for hugetlb faults
and delegates to the appropriate handler depending on the type of fault.
Right now we still have only hugetlb_no_page() but a later patch introduces a
COW fault.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Adam Litke <agl@us.ibm.com>
Cc: William Lee Irwin III <wli@holomorphy.com>
Cc: "Seth, Rohit" <rohit.seth@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
| -rw-r--r-- | mm/hugetlb.c | 34 |
1 files changed, 25 insertions, 9 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c index fdbbbb90caa2..cf8225108b2f 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -376,20 +376,15 @@ out: return page; } -int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, - unsigned long address, int write_access) +int hugetlb_no_page(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long address, pte_t *ptep) { int ret = VM_FAULT_SIGBUS; unsigned long idx; unsigned long size; - pte_t *pte; struct page *page; struct address_space *mapping; - pte = huge_pte_alloc(mm, address); - if (!pte) - goto out; - mapping = vma->vm_file->f_mapping; idx = ((address - vma->vm_start) >> HPAGE_SHIFT) + (vma->vm_pgoff >> (HPAGE_SHIFT - PAGE_SHIFT)); @@ -408,11 +403,11 @@ int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, goto backout; ret = VM_FAULT_MINOR; - if (!pte_none(*pte)) + if (!pte_none(*ptep)) goto backout; add_mm_counter(mm, file_rss, HPAGE_SIZE / PAGE_SIZE); - set_huge_pte_at(mm, address, pte, make_huge_pte(vma, page)); + set_huge_pte_at(mm, address, ptep, make_huge_pte(vma, page)); spin_unlock(&mm->page_table_lock); unlock_page(page); out: @@ -426,6 +421,27 @@ backout: goto out; } +int hugetlb_fault(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long address, int write_access) +{ + pte_t *ptep; + pte_t entry; + + ptep = huge_pte_alloc(mm, address); + if (!ptep) + return VM_FAULT_OOM; + + entry = *ptep; + if (pte_none(entry)) + return hugetlb_no_page(mm, vma, address, ptep); + + /* + * We could get here if another thread instantiated the pte + * before the test above. + */ + return VM_FAULT_MINOR; +} + 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) |