diff options
Diffstat (limited to 'mm/mmap.c')
-rw-r--r-- | mm/mmap.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/mm/mmap.c b/mm/mmap.c index e6ee12344b1..c1868ecdbc5 100644 --- a/mm/mmap.c +++ b/mm/mmap.c @@ -96,7 +96,7 @@ int __vm_enough_memory(long pages, int cap_sys_admin) if (sysctl_overcommit_memory == OVERCOMMIT_GUESS) { unsigned long n; - free = get_page_cache_size(); + free = global_page_state(NR_FILE_PAGES); free += nr_swap_pages; /* @@ -1065,7 +1065,8 @@ munmap_back: vma->vm_start = addr; vma->vm_end = addr + len; vma->vm_flags = vm_flags; - vma->vm_page_prot = protection_map[vm_flags & 0x0f]; + vma->vm_page_prot = protection_map[vm_flags & + (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]; vma->vm_pgoff = pgoff; if (file) { @@ -1089,6 +1090,12 @@ munmap_back: goto free_vma; } + /* Don't make the VMA automatically writable if it's shared, but the + * backer wishes to know when pages are first written to */ + if (vma->vm_ops && vma->vm_ops->page_mkwrite) + vma->vm_page_prot = + protection_map[vm_flags & (VM_READ|VM_WRITE|VM_EXEC)]; + /* We set VM_ACCOUNT in a shared mapping's vm_flags, to inform * shmem_zero_setup (perhaps called through /dev/zero's ->mmap) * that memory reservation must be checked; but that reservation @@ -1921,7 +1928,8 @@ unsigned long do_brk(unsigned long addr, unsigned long len) vma->vm_end = addr + len; vma->vm_pgoff = pgoff; vma->vm_flags = flags; - vma->vm_page_prot = protection_map[flags & 0x0f]; + vma->vm_page_prot = protection_map[flags & + (VM_READ|VM_WRITE|VM_EXEC|VM_SHARED)]; vma_link(mm, vma, prev, rb_link, rb_parent); out: mm->total_vm += len >> PAGE_SHIFT; |