From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
This is another place where DAX assumed that pgtable_t was a pointer.
Open code the important parts of set_huge_zero_page() in DAX and make
set_huge_zero_page() static again.
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Signed-off-by: Matthew Wilcox <willy@xxxxxxxxxxxxxxx>
---
fs/dax.c | 18 ++++++++++++------
include/linux/huge_mm.h | 3 ---
mm/huge_memory.c | 2 +-
3 files changed, 13 insertions(+), 10 deletions(-)
diff --git a/fs/dax.c b/fs/dax.c
index 9daf005..bf9a22b 100644
--- a/fs/dax.c
+++ b/fs/dax.c
@@ -572,18 +572,24 @@ int __dax_pmd_fault(struct vm_area_struct *vma, unsigned long address,
unmap_mapping_range(mapping, pgoff << PAGE_SHIFT, PMD_SIZE, 0);
if (!write && !buffer_mapped(&bh) && buffer_uptodate(&bh)) {
- bool set;
spinlock_t *ptl;
- struct mm_struct *mm = vma->vm_mm;
+ pmd_t entry;
struct page *zero_page = get_huge_zero_page();
+
if (unlikely(!zero_page))
goto fallback;
- ptl = pmd_lock(mm, pmd);
- set = set_huge_zero_page(NULL, mm, vma, pmd_addr, pmd,
- zero_page);
- spin_unlock(ptl);
+ ptl = pmd_lock(vma->vm_mm, pmd);
+ if (!pmd_none(*pmd)) {
+ spin_unlock(ptl);
+ goto fallback;
+ }
+
+ entry = mk_pmd(zero_page, vma->vm_page_prot);
+ entry = pmd_mkhuge(entry);
+ set_pmd_at(vma->vm_mm, pmd_addr, pmd, entry);
result = VM_FAULT_NOPAGE;
+ spin_unlock(ptl);
} else {
sector = bh.b_blocknr << (blkbits - 9);
length = bdev_direct_access(bh.b_bdev, sector, &kaddr, &pfn,
diff --git a/include/linux/huge_mm.h b/include/linux/huge_mm.h
index f9b612f..ecb080d 100644
--- a/include/linux/huge_mm.h
+++ b/include/linux/huge_mm.h
@@ -163,9 +163,6 @@ static inline bool is_huge_zero_pmd(pmd_t pmd)
}
struct page *get_huge_zero_page(void);
-bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
- struct vm_area_struct *vma, unsigned long haddr,
- pmd_t *pmd, struct page *zero_page);
#else /* CONFIG_TRANSPARENT_HUGEPAGE */
#define HPAGE_PMD_SHIFT ({ BUILD_BUG(); 0; })
diff --git a/mm/huge_memory.c b/mm/huge_memory.c
index b51bed1..63c8fe5 100644
--- a/mm/huge_memory.c
+++ b/mm/huge_memory.c
@@ -767,7 +767,7 @@ static inline gfp_t alloc_hugepage_gfpmask(int defrag, gfp_t extra_gfp)
}
/* Caller must hold page table lock. */
-bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
+static bool set_huge_zero_page(pgtable_t pgtable, struct mm_struct *mm,
struct vm_area_struct *vma, unsigned long haddr, pmd_t *pmd,
struct page *zero_page)
{
--
2.1.4
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@xxxxxxxxx. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>