#include <linux/mmzone.h>
#include <linux/bootmem.h>
#include <linux/module.h>
+#include <linux/spinlock.h>
#include <asm/dma.h>
/*
*
* 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)
{
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 = (void *) -1;
+ 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;
}
}
return nr_pages * sizeof(struct page);
}
+/*
+ * Subtle, we encode the real pfn into the mem_map such that
+ * the identity pfn - section_mem_map will return the actual
+ * physical page frame number.
+ */
+static unsigned long sparse_encode_mem_map(struct page *mem_map, unsigned long pnum)
+{
+ return (unsigned long)(mem_map - (section_nr_to_pfn(pnum)));
+}
+
+/*
+ * We need this if we ever free the mem_maps. While not implemented yet,
+ * this function is included for parity with its sibling.
+ */
+static __attribute((unused))
+struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pnum)
+{
+ return ((struct page *)coded_mem_map) + section_nr_to_pfn(pnum);
+}
+
+static int sparse_init_one_section(struct mem_section *ms,
+ unsigned long pnum, struct page *mem_map)
+{
+ if (!valid_section(ms))
+ return -EINVAL;
+
+ ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum);
+
+ return 1;
+}
+
+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)
+ return map;
+
+ map = alloc_bootmem_node(NODE_DATA(nid),
+ sizeof(struct page) * PAGES_PER_SECTION);
+ if (map)
+ return map;
+
+ printk(KERN_WARNING "%s: allocation failed\n", __FUNCTION__);
+ ms->section_mem_map = 0;
+ return NULL;
+}
+
/*
* Allocate the accumulated non-linear sections, allocate a mem_map
* for each and record the physical to section mapping.
{
unsigned long pnum;
struct page *map;
- int nid;
for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) {
- if (!mem_section[pnum].section_mem_map)
+ if (!valid_section_nr(pnum))
continue;
- nid = early_pfn_to_nid(section_nr_to_pfn(pnum));
- map = alloc_remap(nid, sizeof(struct page) * PAGES_PER_SECTION);
+ map = sparse_early_mem_map_alloc(pnum);
if (!map)
- map = alloc_bootmem_node(NODE_DATA(nid),
- sizeof(struct page) * PAGES_PER_SECTION);
- if (!map) {
- mem_section[pnum].section_mem_map = 0;
continue;
- }
-
- /*
- * Subtle, we encode the real pfn into the mem_map such that
- * the identity pfn - section_mem_map will return the actual
- * physical page frame number.
- */
- mem_section[pnum].section_mem_map = map -
- section_nr_to_pfn(pnum);
+ sparse_init_one_section(__nr_to_section(pnum), pnum, map);
}
}
+
+/*
+ * returns the number of sections whose mem_maps were properly
+ * set. If this is <=0, then that means that the passed-in
+ * map was not consumed and must be freed.
+ */
+int sparse_add_one_section(unsigned long start_pfn, int nr_pages, struct page *map)
+{
+ struct mem_section *ms = __pfn_to_section(start_pfn);
+
+ if (ms->section_mem_map & SECTION_MARKED_PRESENT)
+ return -EEXIST;
+
+ ms->section_mem_map |= SECTION_MARKED_PRESENT;
+
+ return sparse_init_one_section(ms, pfn_to_section_nr(start_pfn), map);
+}
projects / linux-2.6 / blobdiff