Handle MAP_FIXED in ia64 arch_get_unmapped_area and
hugetlb_get_unmapped_area(), just call prepare_hugepage_range in the later and
is_hugepage_only_range() in the former.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Acked-by: William Irwin <bill.irwin@oracle.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
        if (len > RGN_MAP_LIMIT)
                return -ENOMEM;
 
+       /* handle fixed mapping: prevent overlap with huge pages */
+       if (flags & MAP_FIXED) {
+               if (is_hugepage_only_range(mm, addr, len))
+                       return -EINVAL;
+               return addr;
+       }
+
 #ifdef CONFIG_HUGETLB_PAGE
        if (REGION_NUMBER(addr) == RGN_HPAGE)
                addr = 0;
 
                return -ENOMEM;
        if (len & ~HPAGE_MASK)
                return -EINVAL;
+
+       /* Handle MAP_FIXED */
+       if (flags & MAP_FIXED) {
+               if (prepare_hugepage_range(addr, len, pgoff))
+                       return -EINVAL;
+               return addr;
+       }
+
        /* This code assumes that RGN_HPAGE != 0. */
        if ((REGION_NUMBER(addr) != RGN_HPAGE) || (addr & (HPAGE_SIZE - 1)))
                addr = HPAGE_REGION_BASE;