[XFS] Fix modular XFS builds (Makefile botch).

[sfrench/cifs-2.6.git] / mm / sparse.c

diff --git a/mm/sparse.c b/mm/sparse.c
index b54e304df4a70c7232dcc9464f69582d68339993..347249a4917afa922f4c8ae5d38fbfe81c189a5a 100644 (file)
--- a/mm/sparse.c
+++ b/mm/sparse.c
@@ -6,6 +6,7 @@
 #include <linux/mmzone.h>
 #include <linux/bootmem.h>
 #include <linux/module.h>
+#include <linux/spinlock.h>
 #include <asm/dma.h>
 
 /*
@@ -13,9 +14,64 @@
  *
  * 1) mem_section      - memory sections, mem_map's for valid memory
  */
-struct mem_section mem_section[NR_MEM_SECTIONS];
+#ifdef CONFIG_SPARSEMEM_EXTREME
+struct mem_section *mem_section[NR_SECTION_ROOTS]
+       ____cacheline_maxaligned_in_smp;
+#else
+struct mem_section mem_section[NR_SECTION_ROOTS][SECTIONS_PER_ROOT]
+       ____cacheline_maxaligned_in_smp;
+#endif
 EXPORT_SYMBOL(mem_section);
 
+#ifdef CONFIG_SPARSEMEM_EXTREME
+static struct mem_section *sparse_index_alloc(int nid)
+{
+       struct mem_section *section = NULL;
+       unsigned long array_size = SECTIONS_PER_ROOT *
+                                  sizeof(struct mem_section);
+
+       section = alloc_bootmem_node(NODE_DATA(nid), array_size);
+
+       if (section)
+               memset(section, 0, array_size);
+
+       return section;
+}
+
+static int sparse_index_init(unsigned long section_nr, int nid)
+{
+       static spinlock_t index_init_lock = SPIN_LOCK_UNLOCKED;
+       unsigned long root = SECTION_NR_TO_ROOT(section_nr);
+       struct mem_section *section;
+       int ret = 0;
+
+       if (mem_section[root])
+               return -EEXIST;
+
+       section = sparse_index_alloc(nid);
+       /*
+        * This lock keeps two different sections from
+        * reallocating for the same index
+        */
+       spin_lock(&index_init_lock);
+
+       if (mem_section[root]) {
+               ret = -EEXIST;
+               goto out;
+       }
+
+       mem_section[root] = section;
+out:
+       spin_unlock(&index_init_lock);
+       return ret;
+}
+#else /* !SPARSEMEM_EXTREME */
+static inline int sparse_index_init(unsigned long section_nr, int nid)
+{
+       return 0;
+}
+#endif
+
 /* Record a memory area against a node. */
 void memory_present(int nid, unsigned long start, unsigned long end)
 {
@@ -24,8 +80,13 @@ void memory_present(int nid, unsigned long start, unsigned long end)
        start &= PAGE_SECTION_MASK;
        for (pfn = start; pfn < end; pfn += PAGES_PER_SECTION) {
                unsigned long section = pfn_to_section_nr(pfn);
-               if (!mem_section[section].section_mem_map)
-                       mem_section[section].section_mem_map = SECTION_MARKED_PRESENT;
+               struct mem_section *ms;
+
+               sparse_index_init(section, nid);
+
+               ms = __nr_to_section(section);
+               if (!ms->section_mem_map)
+                       ms->section_mem_map = SECTION_MARKED_PRESENT;
        }
 }
 
@@ -85,6 +146,7 @@ static struct page *sparse_early_mem_map_alloc(unsigned long pnum)
 {
        struct page *map;
        int nid = early_pfn_to_nid(section_nr_to_pfn(pnum));
+       struct mem_section *ms = __nr_to_section(pnum);
 
        map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION);
        if (map)
@@ -96,7 +158,7 @@ static struct page *sparse_early_mem_map_alloc(unsigned long pnum)
                return map;
 
        printk(KERN_WARNING "%s: allocation failed\n", __FUNCTION__);
-       mem_section[pnum].section_mem_map = 0;
+       ms->section_mem_map = 0;
        return NULL;
 }
 
@@ -114,8 +176,9 @@ void sparse_init(void)
                        continue;
 
                map = sparse_early_mem_map_alloc(pnum);
-               if (map)
-                       sparse_init_one_section(&mem_section[pnum], pnum, map);
+               if (!map)
+                       continue;
+               sparse_init_one_section(__nr_to_section(pnum), pnum, map);
        }
 }