mm: larger stack guard gap, between vmas

[pandora-kernel.git] / arch / ia64 / kernel / sys_ia64.c

diff --git a/arch/ia64/kernel/sys_ia64.c b/arch/ia64/kernel/sys_ia64.c
index 609d500..77c0aff 100644 (file)
--- a/arch/ia64/kernel/sys_ia64.c
+++ b/arch/ia64/kernel/sys_ia64.c
@@ -27,7 +27,8 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len
        long map_shared = (flags & MAP_SHARED);
        unsigned long start_addr, align_mask = PAGE_SIZE - 1;
        struct mm_struct *mm = current->mm;
-       struct vm_area_struct *vma;
+       struct vm_area_struct *vma, *prev;
+       unsigned long prev_end;
 
        if (len > RGN_MAP_LIMIT)
                return -ENOMEM;
@@ -58,7 +59,17 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len
   full_search:
        start_addr = addr = (addr + align_mask) & ~align_mask;
 
-       for (vma = find_vma(mm, addr); ; vma = vma->vm_next) {
+       for (vma = find_vma_prev(mm, addr, &prev); ; prev = vma,
+                                               vma = vma->vm_next) {
+               if (prev) {
+                       prev_end = vm_end_gap(prev);
+                       if (addr < prev_end) {
+                               addr = (prev_end + align_mask) & ~align_mask;
+                               /* If vma already violates gap, forget it */
+                               if (vma && addr > vma->vm_start)
+                                       addr = vma->vm_start;
+                       }
+               }
                /* At this point:  (!vma || addr < vma->vm_end). */
                if (TASK_SIZE - len < addr || RGN_MAP_LIMIT - len < REGION_OFFSET(addr)) {
                        if (start_addr != TASK_UNMAPPED_BASE) {
@@ -68,12 +79,11 @@ arch_get_unmapped_area (struct file *filp, unsigned long addr, unsigned long len
                        }
                        return -ENOMEM;
                }
-               if (!vma || addr + len <= vma->vm_start) {
+               if (!vma || addr + len <= vm_start_gap(vma)) {
                        /* Remember the address where we stopped this search:  */
                        mm->free_area_cache = addr + len;
                        return addr;
                }
-               addr = (vma->vm_end + align_mask) & ~align_mask;
        }
 }