x86_64: allocate sparsemem memmap above 4G

On systems with huge amount of physical memory, VFS cache and memory memmap
may eat all available system memory under 4G, then the system may fail to
allocate swiotlb bounce buffer.

There was a fix for this issue in arch/x86_64/mm/numa.c, but that fix dose
not cover sparsemem model.

This patch add fix to sparsemem model by first try to allocate memmap above
4G.

Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
Acked-by: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Andi Kleen <ak@suse.de>
Cc: <stable@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 6 insertions, 0 deletions

diff --git a/arch/x86_64/mm/init.c b/arch/x86_64/mm/init.c
index 1336da8bdee1..1ad5111aec38 100644
--- a/arch/x86_64/mm/init.c
+++ b/arch/x86_64/mm/init.c
@@ -761,3 +761,9 @@ int in_gate_area_no_task(unsigned long addr)
 {
         return (addr >= VSYSCALL_START) && (addr < VSYSCALL_END);
 }
+
+void *alloc_bootmem_high_node(pg_data_t *pgdat, unsigned long size)
+{
+        return __alloc_bootmem_core(pgdat->bdata, size,
+                        SMP_CACHE_BYTES, (4UL*1024*1024*1024), 0);
+}