diff --git a/Documentation/nommu-mmap.txt b/Documentation/nommu-mmap.txt index 4db7c18bf68c..7714f57caad5 100644 --- a/Documentation/nommu-mmap.txt +++ b/Documentation/nommu-mmap.txt @@ -138,6 +138,16 @@ mode. The former through the usual mechanism, the latter through files created on ramfs or tmpfs mounts. +======= +FUTEXES +======= + +Futexes are supported in NOMMU mode if the arch supports them. An error will +be given if an address passed to the futex system call lies outside the +mappings made by a process or if the mapping in which the address lies does not +support futexes (such as an I/O chardev mapping). + + ============= NO-MMU MREMAP ============= diff --git a/mm/nommu.c b/mm/nommu.c index 23cfa8ec914a..564540662192 100644 --- a/mm/nommu.c +++ b/mm/nommu.c @@ -349,6 +349,15 @@ struct vm_area_struct *find_vma(struct mm_struct *mm, unsigned long addr) } EXPORT_SYMBOL(find_vma); +/* + * find a VMA + * - we don't extend stack VMAs under NOMMU conditions + */ +struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr) +{ + return find_vma(mm, addr); +} + /* * look up the first VMA exactly that exactly matches addr * - should be called with mm->mmap_sem at least held readlocked @@ -1153,11 +1162,6 @@ struct page *follow_page(struct vm_area_struct *vma, unsigned long address, return NULL; } -struct vm_area_struct *find_extend_vma(struct mm_struct *mm, unsigned long addr) -{ - return NULL; -} - int remap_pfn_range(struct vm_area_struct *vma, unsigned long from, unsigned long to, unsigned long size, pgprot_t prot) {