x86-32, numa: Make pgdat allocation use alloc_remap()

pgdat allocation is handled differnetly from other remap allocations -
it's reserved during initialization.  There's no reason to handle this
any differnetly.  Remap allocator is initialized for every node and if
init failed the allocation will fail and pgdat allocation can fall
back to generic code like anyone else.

Remove special init-time pgdat reservation and make allocate_pgdat()
use alloc_remap() like everyone else.

Signed-off-by: Tejun Heo <tj@kernel.org>
Link: http://lkml.kernel.org/r/1301955840-7246-12-git-send-email-tj@kernel.org
Acked-by: Yinghai Lu <yinghai@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>

arch/x86/mm/numa_32.c

@@ -160,9 +160,8 @@ static void __init allocate_pgdat(int nid)
 {
 	char buf[16];
 
-	if (node_has_online_mem(nid) && node_remap_start_vaddr[nid])
-		NODE_DATA(nid) = (pg_data_t *)node_remap_start_vaddr[nid];
-	else {
+	NODE_DATA(nid) = alloc_remap(nid, ALIGN(sizeof(pg_data_t), PAGE_SIZE));
+	if (!NODE_DATA(nid)) {
 		unsigned long pgdat_phys;
 		pgdat_phys = memblock_find_in_range(min_low_pfn<<PAGE_SHIFT,
 				 max_pfn_mapped<<PAGE_SHIFT,
@@ -301,7 +300,7 @@ static __init unsigned long init_alloc_remap(int nid, unsigned long offset)
 
 	node_remap_start_vaddr[nid] = remap_va;
 	node_remap_end_vaddr[nid] = remap_va + size;
-	node_remap_alloc_vaddr[nid] = remap_va + ALIGN(sizeof(pg_data_t), PAGE_SIZE);
+	node_remap_alloc_vaddr[nid] = remap_va;
 
 	printk(KERN_DEBUG "remap_alloc: node %d [%08llx-%08llx) -> [%p-%p)\n",
 	       nid, node_pa, node_pa + size, remap_va, remap_va + size);