The patch titled
hugetlb: follow_hugetlb_page() for write access
has been removed from the -mm tree. Its filename was
hugetlb-follow_hugetlb_page-for-write-access.patch
This patch was dropped because it was merged into mainline or a subsystem tree
------------------------------------------------------
Subject: hugetlb: follow_hugetlb_page() for write access
From: Adam Litke <agl@xxxxxxxxxx>
When calling get_user_pages(), a write flag is passed in by the caller to
indicate if write access is required on the faulted-in pages. Currently,
follow_hugetlb_page() ignores this flag and always faults pages for
read-only access. This can cause data corruption because a device driver
that calls get_user_pages() with write set will not expect COW faults to
occur on the returned pages.
This patch passes the write flag down to follow_hugetlb_page() and makes
sure hugetlb_fault() is called with the right write_access parameter.
[ezk@xxxxxxxxxxxxx: build fix]
Signed-off-by: Adam Litke <agl@xxxxxxxxxx>
Reviewed-by: Ken Chen <kenchen@xxxxxxxxxx>
Cc: David Gibson <hermes@xxxxxxxxxxxxxxxxxxxxx>
Cc: William Lee Irwin III <wli@xxxxxxxxxxxxxx>
Cc: Badari Pulavarty <pbadari@xxxxxxxxxx>
Signed-off-by: Erez Zadok <ezk@xxxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
include/linux/hugetlb.h | 4 ++--
mm/hugetlb.c | 5 +++--
mm/memory.c | 2 +-
3 files changed, 6 insertions(+), 5 deletions(-)
diff -puN include/linux/hugetlb.h~hugetlb-follow_hugetlb_page-for-write-access include/linux/hugetlb.h
--- a/include/linux/hugetlb.h~hugetlb-follow_hugetlb_page-for-write-access
+++ a/include/linux/hugetlb.h
@@ -19,7 +19,7 @@ static inline int is_vm_hugetlb_page(str
int hugetlb_sysctl_handler(struct ctl_table *, int, struct file *, void __user *, size_t *, loff_t *);
int hugetlb_treat_movable_handler(struct ctl_table *, int, struct file *, void __user *, size_t *, loff_t *);
int copy_hugetlb_page_range(struct mm_struct *, struct mm_struct *, struct vm_area_struct *);
-int follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *, struct page **, struct vm_area_struct **, unsigned long *, int *, int);
+int follow_hugetlb_page(struct mm_struct *, struct vm_area_struct *, struct page **, struct vm_area_struct **, unsigned long *, int *, int, int);
void unmap_hugepage_range(struct vm_area_struct *, unsigned long, unsigned long);
void __unmap_hugepage_range(struct vm_area_struct *, unsigned long, unsigned long);
int hugetlb_prefault(struct address_space *, struct vm_area_struct *);
@@ -106,7 +106,7 @@ static inline unsigned long hugetlb_tota
return 0;
}
-#define follow_hugetlb_page(m,v,p,vs,a,b,i) ({ BUG(); 0; })
+#define follow_hugetlb_page(m,v,p,vs,a,b,i,w) ({ BUG(); 0; })
#define follow_huge_addr(mm, addr, write) ERR_PTR(-EINVAL)
#define copy_hugetlb_page_range(src, dst, vma) ({ BUG(); 0; })
#define hugetlb_prefault(mapping, vma) ({ BUG(); 0; })
diff -puN mm/hugetlb.c~hugetlb-follow_hugetlb_page-for-write-access mm/hugetlb.c
--- a/mm/hugetlb.c~hugetlb-follow_hugetlb_page-for-write-access
+++ a/mm/hugetlb.c
@@ -868,7 +868,8 @@ int hugetlb_fault(struct mm_struct *mm,
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 *position, int *length, int i,
+ int write)
{
unsigned long pfn_offset;
unsigned long vaddr = *position;
@@ -890,7 +891,7 @@ int follow_hugetlb_page(struct mm_struct
int ret;
spin_unlock(&mm->page_table_lock);
- ret = hugetlb_fault(mm, vma, vaddr, 0);
+ ret = hugetlb_fault(mm, vma, vaddr, write);
spin_lock(&mm->page_table_lock);
if (!(ret & VM_FAULT_ERROR))
continue;
diff -puN mm/memory.c~hugetlb-follow_hugetlb_page-for-write-access mm/memory.c
--- a/mm/memory.c~hugetlb-follow_hugetlb_page-for-write-access
+++ a/mm/memory.c
@@ -1036,7 +1036,7 @@ int get_user_pages(struct task_struct *t
if (is_vm_hugetlb_page(vma)) {
i = follow_hugetlb_page(mm, vma, pages, vmas,
- &start, &len, i);
+ &start, &len, i, write);
continue;
}
_
Patches currently in -mm which might be from agl@xxxxxxxxxx are
origin.patch
hugetlb-allow-sticky-directory-mount-option.patch
-
To unsubscribe from this list: send the line "unsubscribe mm-commits" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
