diff options
Diffstat (limited to 'mm/memory.c')
| -rw-r--r-- | mm/memory.c | 36 |
1 files changed, 23 insertions, 13 deletions
diff --git a/mm/memory.c b/mm/memory.c index 5d8c2afb07307..7206a634270be 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 |