[PATCH RESEND 3/8] sparc: Start fallback of top-down mmap at mm->mmap_base

[Alexandre Ghiti]

In case of mmap failure in top-down mode, there is no need to go through
the whole address space again for the bottom-up fallback: the goal of this
fallback is to find, as a last resort, space between the top-down mmap base
and the stack, which is the only place not covered by the top-down mmap.

Signed-off-by: Alexandre Ghiti <a...@ghiti.fr>
---
 arch/sparc/kernel/sys_sparc_64.c | 2 +-
 arch/sparc/mm/hugetlbpage.c      | 2 +-
 2 files changed, 2 insertions(+), 2 deletions(-)

diff --git a/arch/sparc/kernel/sys_sparc_64.c b/arch/sparc/kernel/sys_sparc_64.c
index ccc88926bc00..ea1de1e5fa8d 100644
--- a/arch/sparc/kernel/sys_sparc_64.c
+++ b/arch/sparc/kernel/sys_sparc_64.c
@@ -206,7 +206,7 @@ arch_get_unmapped_area_topdown(struct file *filp, const 
unsigned long addr0,
        if (addr & ~PAGE_MASK) {
                VM_BUG_ON(addr != -ENOMEM);
                info.flags = 0;
-               info.low_limit = TASK_UNMAPPED_BASE;
+               info.low_limit = mm->mmap_base;
                info.high_limit = STACK_TOP32;
                addr = vm_unmapped_area(&info);
        }
diff --git a/arch/sparc/mm/hugetlbpage.c b/arch/sparc/mm/hugetlbpage.c
index f78793a06bbd..9c67f805abc8 100644
--- a/arch/sparc/mm/hugetlbpage.c
+++ b/arch/sparc/mm/hugetlbpage.c
@@ -86,7 +86,7 @@ hugetlb_get_unmapped_area_topdown(struct file *filp, const 
unsigned long addr0,
        if (addr & ~PAGE_MASK) {
                VM_BUG_ON(addr != -ENOMEM);
                info.flags = 0;
-               info.low_limit = TASK_UNMAPPED_BASE;
+               info.low_limit = mm->mmap_base;
                info.high_limit = STACK_TOP32;
                addr = vm_unmapped_area(&info);
        }
-- 
2.20.1