diff options
Diffstat (limited to 'mm/sparse.c')
| -rw-r--r-- | mm/sparse.c | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/mm/sparse.c b/mm/sparse.c index 347249a4917a..0d3bd4bf3aaa 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -72,6 +72,31 @@ static inline int sparse_index_init(unsigned long section_nr, int nid) } #endif +/* + * Although written for the SPARSEMEM_EXTREME case, this happens + * to also work for the flat array case becase + * NR_SECTION_ROOTS==NR_MEM_SECTIONS. + */ +int __section_nr(struct mem_section* ms) +{ + unsigned long root_nr; + struct mem_section* root; + + for (root_nr = 0; + root_nr < NR_MEM_SECTIONS; + root_nr += SECTIONS_PER_ROOT) { + root = __nr_to_section(root_nr); + + if (!root) + continue; + + if ((ms >= root) && (ms < (root + SECTIONS_PER_ROOT))) + break; + } + + return (root_nr * SECTIONS_PER_ROOT) + (ms - root); +} + /* Record a memory area against a node. */ void memory_present(int nid, unsigned long start, unsigned long end) { |