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Diffstat (limited to 'mm')
-rw-r--r--mm/hugetlb.c40
-rw-r--r--mm/userfaultfd.c37
2 files changed, 49 insertions, 28 deletions
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index b105a455124d..533e5a26e437 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -39,7 +39,6 @@
#include <linux/hugetlb.h>
#include <linux/hugetlb_cgroup.h>
#include <linux/node.h>
-#include <linux/userfaultfd_k.h>
#include <linux/page_owner.h>
#include "internal.h"
@@ -4865,8 +4864,10 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
struct vm_area_struct *dst_vma,
unsigned long dst_addr,
unsigned long src_addr,
+ enum mcopy_atomic_mode mode,
struct page **pagep)
{
+ bool is_continue = (mode == MCOPY_ATOMIC_CONTINUE);
struct address_space *mapping;
pgoff_t idx;
unsigned long size;
@@ -4876,8 +4877,17 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
spinlock_t *ptl;
int ret;
struct page *page;
+ int writable;
- if (!*pagep) {
+ mapping = dst_vma->vm_file->f_mapping;
+ idx = vma_hugecache_offset(h, dst_vma, dst_addr);
+
+ if (is_continue) {
+ ret = -EFAULT;
+ page = find_lock_page(mapping, idx);
+ if (!page)
+ goto out;
+ } else if (!*pagep) {
ret = -ENOMEM;
page = alloc_huge_page(dst_vma, dst_addr, 0);
if (IS_ERR(page))
@@ -4906,13 +4916,8 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
*/
__SetPageUptodate(page);
- mapping = dst_vma->vm_file->f_mapping;
- idx = vma_hugecache_offset(h, dst_vma, dst_addr);
-
- /*
- * If shared, add to page cache
- */
- if (vm_shared) {
+ /* Add shared, newly allocated pages to the page cache. */
+ if (vm_shared && !is_continue) {
size = i_size_read(mapping->host) >> huge_page_shift(h);
ret = -EFAULT;
if (idx >= size)
@@ -4957,8 +4962,14 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
hugepage_add_new_anon_rmap(page, dst_vma, dst_addr);
}
- _dst_pte = make_huge_pte(dst_vma, page, dst_vma->vm_flags & VM_WRITE);
- if (dst_vma->vm_flags & VM_WRITE)
+ /* For CONTINUE on a non-shared VMA, don't set VM_WRITE for CoW. */
+ if (is_continue && !vm_shared)
+ writable = 0;
+ else
+ writable = dst_vma->vm_flags & VM_WRITE;
+
+ _dst_pte = make_huge_pte(dst_vma, page, writable);
+ if (writable)
_dst_pte = huge_pte_mkdirty(_dst_pte);
_dst_pte = pte_mkyoung(_dst_pte);
@@ -4972,15 +4983,16 @@ int hugetlb_mcopy_atomic_pte(struct mm_struct *dst_mm,
update_mmu_cache(dst_vma, dst_addr, dst_pte);
spin_unlock(ptl);
- SetHPageMigratable(page);
- if (vm_shared)
+ if (!is_continue)
+ SetHPageMigratable(page);
+ if (vm_shared || is_continue)
unlock_page(page);
ret = 0;
out:
return ret;
out_release_unlock:
spin_unlock(ptl);
- if (vm_shared)
+ if (vm_shared || is_continue)
unlock_page(page);
out_release_nounlock:
put_page(page);
diff --git a/mm/userfaultfd.c b/mm/userfaultfd.c
index 063cbb17e8d8..e14b3820c6a8 100644
--- a/mm/userfaultfd.c
+++ b/mm/userfaultfd.c
@@ -207,7 +207,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
unsigned long dst_start,
unsigned long src_start,
unsigned long len,
- bool zeropage)
+ enum mcopy_atomic_mode mode)
{
int vm_alloc_shared = dst_vma->vm_flags & VM_SHARED;
int vm_shared = dst_vma->vm_flags & VM_SHARED;
@@ -227,7 +227,7 @@ static __always_inline ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
* by THP. Since we can not reliably insert a zero page, this
* feature is not supported.
*/
- if (zeropage) {
+ if (mode == MCOPY_ATOMIC_ZEROPAGE) {
mmap_read_unlock(dst_mm);
return -EINVAL;
}
@@ -273,8 +273,6 @@ retry:
}
while (src_addr < src_start + len) {
- pte_t dst_pteval;
-
BUG_ON(dst_addr >= dst_start + len);
/*
@@ -297,16 +295,16 @@ retry:
goto out_unlock;
}
- err = -EEXIST;
- dst_pteval = huge_ptep_get(dst_pte);
- if (!huge_pte_none(dst_pteval)) {
+ if (mode != MCOPY_ATOMIC_CONTINUE &&
+ !huge_pte_none(huge_ptep_get(dst_pte))) {
+ err = -EEXIST;
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
i_mmap_unlock_read(mapping);
goto out_unlock;
}
err = hugetlb_mcopy_atomic_pte(dst_mm, dst_pte, dst_vma,
- dst_addr, src_addr, &page);
+ dst_addr, src_addr, mode, &page);
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
i_mmap_unlock_read(mapping);
@@ -408,7 +406,7 @@ extern ssize_t __mcopy_atomic_hugetlb(struct mm_struct *dst_mm,
unsigned long dst_start,
unsigned long src_start,
unsigned long len,
- bool zeropage);
+ enum mcopy_atomic_mode mode);
#endif /* CONFIG_HUGETLB_PAGE */
static __always_inline ssize_t mfill_atomic_pte(struct mm_struct *dst_mm,
@@ -458,7 +456,7 @@ static __always_inline ssize_t __mcopy_atomic(struct mm_struct *dst_mm,
unsigned long dst_start,
unsigned long src_start,
unsigned long len,
- bool zeropage,
+ enum mcopy_atomic_mode mcopy_mode,
bool *mmap_changing,
__u64 mode)
{
@@ -469,6 +467,7 @@ static __always_inline ssize_t __mcopy_atomic(struct mm_struct *dst_mm,
long copied;
struct page *page;
bool wp_copy;
+ bool zeropage = (mcopy_mode == MCOPY_ATOMIC_ZEROPAGE);
/*
* Sanitize the command parameters:
@@ -527,10 +526,12 @@ retry:
*/
if (is_vm_hugetlb_page(dst_vma))
return __mcopy_atomic_hugetlb(dst_mm, dst_vma, dst_start,
- src_start, len, zeropage);
+ src_start, len, mcopy_mode);
if (!vma_is_anonymous(dst_vma) && !vma_is_shmem(dst_vma))
goto out_unlock;
+ if (mcopy_mode == MCOPY_ATOMIC_CONTINUE)
+ goto out_unlock;
/*
* Ensure the dst_vma has a anon_vma or this page
@@ -626,14 +627,22 @@ ssize_t mcopy_atomic(struct mm_struct *dst_mm, unsigned long dst_start,
unsigned long src_start, unsigned long len,
bool *mmap_changing, __u64 mode)
{
- return __mcopy_atomic(dst_mm, dst_start, src_start, len, false,
- mmap_changing, mode);
+ return __mcopy_atomic(dst_mm, dst_start, src_start, len,
+ MCOPY_ATOMIC_NORMAL, mmap_changing, mode);
}
ssize_t mfill_zeropage(struct mm_struct *dst_mm, unsigned long start,
unsigned long len, bool *mmap_changing)
{
- return __mcopy_atomic(dst_mm, start, 0, len, true, mmap_changing, 0);
+ return __mcopy_atomic(dst_mm, start, 0, len, MCOPY_ATOMIC_ZEROPAGE,
+ mmap_changing, 0);
+}
+
+ssize_t mcopy_continue(struct mm_struct *dst_mm, unsigned long start,
+ unsigned long len, bool *mmap_changing)
+{
+ return __mcopy_atomic(dst_mm, start, 0, len, MCOPY_ATOMIC_CONTINUE,
+ mmap_changing, 0);
}
int mwriteprotect_range(struct mm_struct *dst_mm, unsigned long start,
generated by cgit v1.2.3 (git 2.39.0) at 2025-03-10 09:51:23 +0300