path: root/mm/sparse-vmemmap.c
diff options
authorJohannes Weiner <>2013-04-29 15:07:50 -0700
committerLinus Torvalds <>2013-04-29 15:54:35 -0700
commit0aad818b2de455f1bfd7ef87c28cdbbaaed9a699 (patch)
treea86fe62f7c740d431f76bd2262abae5825e1a21e /mm/sparse-vmemmap.c
parent055e4fd96e95b0eee0d92fd54a26be7f0d3bcad0 (diff)
sparse-vmemmap: specify vmemmap population range in bytes
The sparse code, when asking the architecture to populate the vmemmap, specifies the section range as a starting page and a number of pages. This is an awkward interface, because none of the arch-specific code actually thinks of the range in terms of 'struct page' units and always translates it to bytes first. In addition, later patches mix huge page and regular page backing for the vmemmap. For this, they need to call vmemmap_populate_basepages() on sub-section ranges with PAGE_SIZE and PMD_SIZE in mind. But these are not necessarily multiples of the 'struct page' size and so this unit is too coarse. Just translate the section range into bytes once in the generic sparse code, then pass byte ranges down the stack. Signed-off-by: Johannes Weiner <> Cc: Ben Hutchings <> Cc: Bernhard Schmidt <> Cc: Johannes Weiner <> Cc: Russell King <> Cc: Ingo Molnar <> Cc: Thomas Gleixner <> Cc: "H. Peter Anvin" <> Cc: Benjamin Herrenschmidt <> Cc: "Luck, Tony" <> Cc: Heiko Carstens <> Acked-by: David S. Miller <> Tested-by: David S. Miller <> Cc: Wu Fengguang <> Signed-off-by: Andrew Morton <> Signed-off-by: Linus Torvalds <>
Diffstat (limited to 'mm/sparse-vmemmap.c')
1 files changed, 12 insertions, 7 deletions
diff --git a/mm/sparse-vmemmap.c b/mm/sparse-vmemmap.c
index 22b7e18e9dea..27eeab3be757 100644
--- a/mm/sparse-vmemmap.c
+++ b/mm/sparse-vmemmap.c
@@ -147,11 +147,10 @@ pgd_t * __meminit vmemmap_pgd_populate(unsigned long addr, int node)
return pgd;
-int __meminit vmemmap_populate_basepages(struct page *start_page,
- unsigned long size, int node)
+int __meminit vmemmap_populate_basepages(unsigned long start,
+ unsigned long end, int node)
- unsigned long addr = (unsigned long)start_page;
- unsigned long end = (unsigned long)(start_page + size);
+ unsigned long addr = start;
pgd_t *pgd;
pud_t *pud;
pmd_t *pmd;
@@ -178,9 +177,15 @@ int __meminit vmemmap_populate_basepages(struct page *start_page,
struct page * __meminit sparse_mem_map_populate(unsigned long pnum, int nid)
- struct page *map = pfn_to_page(pnum * PAGES_PER_SECTION);
- int error = vmemmap_populate(map, PAGES_PER_SECTION, nid);
- if (error)
+ unsigned long start;
+ unsigned long end;
+ struct page *map;
+ map = pfn_to_page(pnum * PAGES_PER_SECTION);
+ start = (unsigned long)map;
+ end = (unsigned long)(map + PAGES_PER_SECTION);
+ if (vmemmap_populate(start, end, nid))
return NULL;
return map;