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Diffstat (limited to 'mm/pagewalk.c')
-rw-r--r--mm/pagewalk.c124
1 files changed, 72 insertions, 52 deletions
diff --git a/mm/pagewalk.c b/mm/pagewalk.c
index 8a92a961a2ee..b8762b673a3d 100644
--- a/mm/pagewalk.c
+++ b/mm/pagewalk.c
@@ -9,10 +9,11 @@ static int walk_pte_range(pmd_t *pmd, unsigned long addr, unsigned long end,
{
pte_t *pte;
int err = 0;
+ const struct mm_walk_ops *ops = walk->ops;
pte = pte_offset_map(pmd, addr);
for (;;) {
- err = walk->pte_entry(pte, addr, addr + PAGE_SIZE, walk);
+ err = ops->pte_entry(pte, addr, addr + PAGE_SIZE, walk);
if (err)
break;
addr += PAGE_SIZE;
@@ -30,6 +31,7 @@ static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
{
pmd_t *pmd;
unsigned long next;
+ const struct mm_walk_ops *ops = walk->ops;
int err = 0;
pmd = pmd_offset(pud, addr);
@@ -37,8 +39,8 @@ static int walk_pmd_range(pud_t *pud, unsigned long addr, unsigned long end,
again:
next = pmd_addr_end(addr, end);
if (pmd_none(*pmd) || !walk->vma) {
- if (walk->pte_hole)
- err = walk->pte_hole(addr, next, walk);
+ if (ops->pte_hole)
+ err = ops->pte_hole(addr, next, walk);
if (err)
break;
continue;
@@ -47,8 +49,8 @@ again:
* This implies that each ->pmd_entry() handler
* needs to know about pmd_trans_huge() pmds
*/
- if (walk->pmd_entry)
- err = walk->pmd_entry(pmd, addr, next, walk);
+ if (ops->pmd_entry)
+ err = ops->pmd_entry(pmd, addr, next, walk);
if (err)
break;
@@ -56,7 +58,7 @@ again:
* Check this here so we only break down trans_huge
* pages when we _need_ to
*/
- if (!walk->pte_entry)
+ if (!ops->pte_entry)
continue;
split_huge_pmd(walk->vma, pmd, addr);
@@ -75,6 +77,7 @@ static int walk_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
{
pud_t *pud;
unsigned long next;
+ const struct mm_walk_ops *ops = walk->ops;
int err = 0;
pud = pud_offset(p4d, addr);
@@ -82,18 +85,18 @@ static int walk_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
again:
next = pud_addr_end(addr, end);
if (pud_none(*pud) || !walk->vma) {
- if (walk->pte_hole)
- err = walk->pte_hole(addr, next, walk);
+ if (ops->pte_hole)
+ err = ops->pte_hole(addr, next, walk);
if (err)
break;
continue;
}
- if (walk->pud_entry) {
+ if (ops->pud_entry) {
spinlock_t *ptl = pud_trans_huge_lock(pud, walk->vma);
if (ptl) {
- err = walk->pud_entry(pud, addr, next, walk);
+ err = ops->pud_entry(pud, addr, next, walk);
spin_unlock(ptl);
if (err)
break;
@@ -105,7 +108,7 @@ static int walk_pud_range(p4d_t *p4d, unsigned long addr, unsigned long end,
if (pud_none(*pud))
goto again;
- if (walk->pmd_entry || walk->pte_entry)
+ if (ops->pmd_entry || ops->pte_entry)
err = walk_pmd_range(pud, addr, next, walk);
if (err)
break;
@@ -119,19 +122,20 @@ static int walk_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
{
p4d_t *p4d;
unsigned long next;
+ const struct mm_walk_ops *ops = walk->ops;
int err = 0;
p4d = p4d_offset(pgd, addr);
do {
next = p4d_addr_end(addr, end);
if (p4d_none_or_clear_bad(p4d)) {
- if (walk->pte_hole)
- err = walk->pte_hole(addr, next, walk);
+ if (ops->pte_hole)
+ err = ops->pte_hole(addr, next, walk);
if (err)
break;
continue;
}
- if (walk->pmd_entry || walk->pte_entry)
+ if (ops->pmd_entry || ops->pte_entry)
err = walk_pud_range(p4d, addr, next, walk);
if (err)
break;
@@ -145,19 +149,20 @@ static int walk_pgd_range(unsigned long addr, unsigned long end,
{
pgd_t *pgd;
unsigned long next;
+ const struct mm_walk_ops *ops = walk->ops;
int err = 0;
pgd = pgd_offset(walk->mm, addr);
do {
next = pgd_addr_end(addr, end);
if (pgd_none_or_clear_bad(pgd)) {
- if (walk->pte_hole)
- err = walk->pte_hole(addr, next, walk);
+ if (ops->pte_hole)
+ err = ops->pte_hole(addr, next, walk);
if (err)
break;
continue;
}
- if (walk->pmd_entry || walk->pte_entry)
+ if (ops->pmd_entry || ops->pte_entry)
err = walk_p4d_range(pgd, addr, next, walk);
if (err)
break;
@@ -183,6 +188,7 @@ static int walk_hugetlb_range(unsigned long addr, unsigned long end,
unsigned long hmask = huge_page_mask(h);
unsigned long sz = huge_page_size(h);
pte_t *pte;
+ const struct mm_walk_ops *ops = walk->ops;
int err = 0;
do {
@@ -190,9 +196,9 @@ static int walk_hugetlb_range(unsigned long addr, unsigned long end,
pte = huge_pte_offset(walk->mm, addr & hmask, sz);
if (pte)
- err = walk->hugetlb_entry(pte, hmask, addr, next, walk);
- else if (walk->pte_hole)
- err = walk->pte_hole(addr, next, walk);
+ err = ops->hugetlb_entry(pte, hmask, addr, next, walk);
+ else if (ops->pte_hole)
+ err = ops->pte_hole(addr, next, walk);
if (err)
break;
@@ -220,9 +226,10 @@ static int walk_page_test(unsigned long start, unsigned long end,
struct mm_walk *walk)
{
struct vm_area_struct *vma = walk->vma;
+ const struct mm_walk_ops *ops = walk->ops;
- if (walk->test_walk)
- return walk->test_walk(start, end, walk);
+ if (ops->test_walk)
+ return ops->test_walk(start, end, walk);
/*
* vma(VM_PFNMAP) doesn't have any valid struct pages behind VM_PFNMAP
@@ -234,8 +241,8 @@ static int walk_page_test(unsigned long start, unsigned long end,
*/
if (vma->vm_flags & VM_PFNMAP) {
int err = 1;
- if (walk->pte_hole)
- err = walk->pte_hole(start, end, walk);
+ if (ops->pte_hole)
+ err = ops->pte_hole(start, end, walk);
return err ? err : 1;
}
return 0;
@@ -248,7 +255,7 @@ static int __walk_page_range(unsigned long start, unsigned long end,
struct vm_area_struct *vma = walk->vma;
if (vma && is_vm_hugetlb_page(vma)) {
- if (walk->hugetlb_entry)
+ if (walk->ops->hugetlb_entry)
err = walk_hugetlb_range(start, end, walk);
} else
err = walk_pgd_range(start, end, walk);
@@ -258,11 +265,13 @@ static int __walk_page_range(unsigned long start, unsigned long end,
/**
* walk_page_range - walk page table with caller specific callbacks
- * @start: start address of the virtual address range
- * @end: end address of the virtual address range
- * @walk: mm_walk structure defining the callbacks and the target address space
+ * @mm: mm_struct representing the target process of page table walk
+ * @start: start address of the virtual address range
+ * @end: end address of the virtual address range
+ * @ops: operation to call during the walk
+ * @private: private data for callbacks' usage
*
- * Recursively walk the page table tree of the process represented by @walk->mm
+ * Recursively walk the page table tree of the process represented by @mm
* within the virtual address range [@start, @end). During walking, we can do
* some caller-specific works for each entry, by setting up pmd_entry(),
* pte_entry(), and/or hugetlb_entry(). If you don't set up for some of these
@@ -278,47 +287,52 @@ static int __walk_page_range(unsigned long start, unsigned long end,
*
* Before starting to walk page table, some callers want to check whether
* they really want to walk over the current vma, typically by checking
- * its vm_flags. walk_page_test() and @walk->test_walk() are used for this
+ * its vm_flags. walk_page_test() and @ops->test_walk() are used for this
* purpose.
*
* struct mm_walk keeps current values of some common data like vma and pmd,
* which are useful for the access from callbacks. If you want to pass some
- * caller-specific data to callbacks, @walk->private should be helpful.
+ * caller-specific data to callbacks, @private should be helpful.
*
* Locking:
- * Callers of walk_page_range() and walk_page_vma() should hold
- * @walk->mm->mmap_sem, because these function traverse vma list and/or
- * access to vma's data.
+ * Callers of walk_page_range() and walk_page_vma() should hold @mm->mmap_sem,
+ * because these function traverse vma list and/or access to vma's data.
*/
-int walk_page_range(unsigned long start, unsigned long end,
- struct mm_walk *walk)
+int walk_page_range(struct mm_struct *mm, unsigned long start,
+ unsigned long end, const struct mm_walk_ops *ops,
+ void *private)
{
int err = 0;
unsigned long next;
struct vm_area_struct *vma;
+ struct mm_walk walk = {
+ .ops = ops,
+ .mm = mm,
+ .private = private,
+ };
if (start >= end)
return -EINVAL;
- if (!walk->mm)
+ if (!walk.mm)
return -EINVAL;
- VM_BUG_ON_MM(!rwsem_is_locked(&walk->mm->mmap_sem), walk->mm);
+ VM_BUG_ON_MM(!rwsem_is_locked(&walk.mm->mmap_sem), walk.mm);
- vma = find_vma(walk->mm, start);
+ vma = find_vma(walk.mm, start);
do {
if (!vma) { /* after the last vma */
- walk->vma = NULL;
+ walk.vma = NULL;
next = end;
} else if (start < vma->vm_start) { /* outside vma */
- walk->vma = NULL;
+ walk.vma = NULL;
next = min(end, vma->vm_start);
} else { /* inside vma */
- walk->vma = vma;
+ walk.vma = vma;
next = min(end, vma->vm_end);
vma = vma->vm_next;
- err = walk_page_test(start, next, walk);
+ err = walk_page_test(start, next, &walk);
if (err > 0) {
/*
* positive return values are purely for
@@ -331,28 +345,34 @@ int walk_page_range(unsigned long start, unsigned long end,
if (err < 0)
break;
}
- if (walk->vma || walk->pte_hole)
- err = __walk_page_range(start, next, walk);
+ if (walk.vma || walk.ops->pte_hole)
+ err = __walk_page_range(start, next, &walk);
if (err)
break;
} while (start = next, start < end);
return err;
}
-int walk_page_vma(struct vm_area_struct *vma, struct mm_walk *walk)
+int walk_page_vma(struct vm_area_struct *vma, const struct mm_walk_ops *ops,
+ void *private)
{
+ struct mm_walk walk = {
+ .ops = ops,
+ .mm = vma->vm_mm,
+ .vma = vma,
+ .private = private,
+ };
int err;
- if (!walk->mm)
+ if (!walk.mm)
return -EINVAL;
- VM_BUG_ON(!rwsem_is_locked(&walk->mm->mmap_sem));
- VM_BUG_ON(!vma);
- walk->vma = vma;
- err = walk_page_test(vma->vm_start, vma->vm_end, walk);
+ VM_BUG_ON(!rwsem_is_locked(&vma->vm_mm->mmap_sem));
+
+ err = walk_page_test(vma->vm_start, vma->vm_end, &walk);
if (err > 0)
return 0;
if (err < 0)
return err;
- return __walk_page_range(vma->vm_start, vma->vm_end, walk);
+ return __walk_page_range(vma->vm_start, vma->vm_end, &walk);
}
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-12-24 21:22:27 +0000