[PATCH] NOMMU: make SYSV SHM nattch work correctly

[karo-tx-linux.git] / mm / nommu.c

diff --git a/mm/nommu.c b/mm/nommu.c
index ba6df4d2997922a337dbd7b76e67ee822cb2d371..cbbc1377481981ff26e065dbade356ec90ac0728 100644 (file)
--- a/mm/nommu.c
+++ b/mm/nommu.c
@@ -826,6 +826,11 @@ unsigned long do_mmap_pgoff(struct file *file,
                unsigned long pglen = (len + PAGE_SIZE - 1) >> PAGE_SHIFT;
                unsigned long vmpglen;
 
+               /* suppress VMA sharing for shared regions */
+               if (vm_flags & VM_SHARED &&
+                   capabilities & BDI_CAP_MAP_DIRECT)
+                       goto dont_share_VMAs;
+
                for (rb = rb_first(&nommu_vma_tree); rb; rb = rb_next(rb)) {
                        vma = rb_entry(rb, struct vm_area_struct, vm_rb);
 
@@ -859,6 +864,7 @@ unsigned long do_mmap_pgoff(struct file *file,
                        goto shared;
                }
 
+       dont_share_VMAs:
                vma = NULL;
 
                /* obtain the address at which to make a shared mapping