diff options
| author | Matthew Wilcox | 2015-09-08 14:58:48 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2015-09-08 15:35:28 -0700 |
| commit | b96375f74a6d4f39fc6cbdc0bce5175115c7f96f (patch) | |
| tree | cadd8fed9bf3c44ed91e435d0099151767d9b34d | |
| parent | 4897c7655d9419ba7e62bac145ec6a1847134d93 (diff) | |
mm: add a pmd_fault handler
Allow non-anonymous VMAs to provide huge pages in response to a page fault.
Signed-off-by: Matthew Wilcox <willy@linux.intel.com>
Cc: Hillf Danton <dhillf@gmail.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Theodore Ts'o <tytso@mit.edu>
Cc: Jan Kara <jack@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
| -rw-r--r-- | include/linux/mm.h | 2 | ||||
| -rw-r--r-- | mm/memory.c | 30 |
2 files changed, 26 insertions, 6 deletions
diff --git a/include/linux/mm.h b/include/linux/mm.h index dfb7ce05f1e3..e1fbd18b8c4b 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -249,6 +249,8 @@ struct vm_operations_struct { void (*close)(struct vm_area_struct * area); int (*mremap)(struct vm_area_struct * area); int (*fault)(struct vm_area_struct *vma, struct vm_fault *vmf); + int (*pmd_fault)(struct vm_area_struct *, unsigned long address, + pmd_t *, unsigned int flags); void (*map_pages)(struct vm_area_struct *vma, struct vm_fault *vmf); /* notification that a previously read-only page is about to become diff --git a/mm/memory.c b/mm/memory.c index 882c9d7ae2f5..a3f9a8ccec0f 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -3232,6 +3232,27 @@ out: return 0; } +static int create_huge_pmd(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long address, pmd_t *pmd, unsigned int flags) +{ + if (!vma->vm_ops) + return do_huge_pmd_anonymous_page(mm, vma, address, pmd, flags); + if (vma->vm_ops->pmd_fault) + return vma->vm_ops->pmd_fault(vma, address, pmd, flags); + return VM_FAULT_FALLBACK; +} + +static int wp_huge_pmd(struct mm_struct *mm, struct vm_area_struct *vma, + unsigned long address, pmd_t *pmd, pmd_t orig_pmd, + unsigned int flags) +{ + if (!vma->vm_ops) + return do_huge_pmd_wp_page(mm, vma, address, pmd, orig_pmd); + if (vma->vm_ops->pmd_fault) + return vma->vm_ops->pmd_fault(vma, address, pmd, flags); + return VM_FAULT_FALLBACK; +} + /* * These routines also need to handle stuff like marking pages dirty * and/or accessed for architectures that don't do it in hardware (most @@ -3334,10 +3355,7 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, if (!pmd) return VM_FAULT_OOM; if (pmd_none(*pmd) && transparent_hugepage_enabled(vma)) { - int ret = VM_FAULT_FALLBACK; - if (!vma->vm_ops) - ret = do_huge_pmd_anonymous_page(mm, vma, address, - pmd, flags); + int ret = create_huge_pmd(mm, vma, address, pmd, flags); if (!(ret & VM_FAULT_FALLBACK)) return ret; } else { @@ -3361,8 +3379,8 @@ static int __handle_mm_fault(struct mm_struct *mm, struct vm_area_struct *vma, orig_pmd, pmd); if (dirty && !pmd_write(orig_pmd)) { - ret = do_huge_pmd_wp_page(mm, vma, address, pmd, - orig_pmd); + ret = wp_huge_pmd(mm, vma, address, pmd, + orig_pmd, flags); if (!(ret & VM_FAULT_FALLBACK)) return ret; } else { |