[SPARC64]: Top-down address space allocation for 32-bit tasks.

Currently allocations are very constrained for 32-bit processes.
It grows down-up from 0x70000000 to 0xf0000000 which gives about
2GB of stack + dynamic mmap() space.

So support the top-down method, and we need to override the
generic helper function in order to deal with D-cache coloring.

With these changes I was able to squeeze out a mmap() just over
3.6GB in size in a 32-bit process.

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/arch/sparc64/kernel/binfmt_aout32.c b/arch/sparc64/kernel/binfmt_aout32.c
index cb9ecd0172c0..d7caa60a0074 100644
--- a/arch/sparc64/kernel/binfmt_aout32.c
+++ b/arch/sparc64/kernel/binfmt_aout32.c
@@ -239,6 +239,8 @@ static int load_aout32_binary(struct linux_binprm * bprm, struct pt_regs * regs)
                 (current->mm->start_data = N_DATADDR(ex));
         current->mm->brk = ex.a_bss +
                 (current->mm->start_brk = N_BSSADDR(ex));
+        current->mm->free_area_cache = current->mm->mmap_base;
+        current->mm->cached_hole_size = 0;
 
         current->mm->mmap = NULL;
         compute_creds(bprm);