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Diffstat (limited to 'mm/memory.c')
-rw-r--r--mm/memory.c36
1 files changed, 23 insertions, 13 deletions
diff --git a/mm/memory.c b/mm/memory.c
index 5d8c2afb0730..7206a634270b 100644
--- a/mm/memory.c
+++ b/mm/memory.c
@@ -817,17 +817,12 @@ static void print_bad_pte(struct vm_area_struct *vma, unsigned long addr,
* PFNMAP mappings in order to support COWable mappings.
*
*/
-#ifdef __HAVE_ARCH_PTE_SPECIAL
-# define HAVE_PTE_SPECIAL 1
-#else
-# define HAVE_PTE_SPECIAL 0
-#endif
struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
pte_t pte, bool with_public_device)
{
unsigned long pfn = pte_pfn(pte);
- if (HAVE_PTE_SPECIAL) {
+ if (IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL)) {
if (likely(!pte_special(pte)))
goto check_pfn;
if (vma->vm_ops && vma->vm_ops->find_special_page)
@@ -862,7 +857,7 @@ struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
return NULL;
}
- /* !HAVE_PTE_SPECIAL case follows: */
+ /* !CONFIG_ARCH_HAS_PTE_SPECIAL case follows: */
if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
if (vma->vm_flags & VM_MIXEDMAP) {
@@ -881,6 +876,7 @@ struct page *_vm_normal_page(struct vm_area_struct *vma, unsigned long addr,
if (is_zero_pfn(pfn))
return NULL;
+
check_pfn:
if (unlikely(pfn > highest_memmap_pfn)) {
print_bad_pte(vma, addr, pte, NULL);
@@ -904,7 +900,7 @@ struct page *vm_normal_page_pmd(struct vm_area_struct *vma, unsigned long addr,
/*
* There is no pmd_special() but there may be special pmds, e.g.
* in a direct-access (dax) mapping, so let's just replicate the
- * !HAVE_PTE_SPECIAL case from vm_normal_page() here.
+ * !CONFIG_ARCH_HAS_PTE_SPECIAL case from vm_normal_page() here.
*/
if (unlikely(vma->vm_flags & (VM_PFNMAP|VM_MIXEDMAP))) {
if (vma->vm_flags & VM_MIXEDMAP) {
@@ -1932,7 +1928,8 @@ static int __vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
* than insert_pfn). If a zero_pfn were inserted into a VM_MIXEDMAP
* without pte special, it would there be refcounted as a normal page.
*/
- if (!HAVE_PTE_SPECIAL && !pfn_t_devmap(pfn) && pfn_t_valid(pfn)) {
+ if (!IS_ENABLED(CONFIG_ARCH_HAS_PTE_SPECIAL) &&
+ !pfn_t_devmap(pfn) && pfn_t_valid(pfn)) {
struct page *page;
/*
@@ -1954,12 +1951,25 @@ int vm_insert_mixed(struct vm_area_struct *vma, unsigned long addr,
}
EXPORT_SYMBOL(vm_insert_mixed);
-int vm_insert_mixed_mkwrite(struct vm_area_struct *vma, unsigned long addr,
- pfn_t pfn)
+/*
+ * If the insertion of PTE failed because someone else already added a
+ * different entry in the mean time, we treat that as success as we assume
+ * the same entry was actually inserted.
+ */
+
+vm_fault_t vmf_insert_mixed_mkwrite(struct vm_area_struct *vma,
+ unsigned long addr, pfn_t pfn)
{
- return __vm_insert_mixed(vma, addr, pfn, true);
+ int err;
+
+ err = __vm_insert_mixed(vma, addr, pfn, true);
+ if (err == -ENOMEM)
+ return VM_FAULT_OOM;
+ if (err < 0 && err != -EBUSY)
+ return VM_FAULT_SIGBUS;
+ return VM_FAULT_NOPAGE;
}
-EXPORT_SYMBOL(vm_insert_mixed_mkwrite);
+EXPORT_SYMBOL(vmf_insert_mixed_mkwrite);
/*
* maps a range of physical memory into the requested pages. the old