From 540557b9439ec19668553830c90222f9fb0c2e95 Mon Sep 17 00:00:00 2001 From: Andy Whitcroft Date: Tue, 16 Oct 2007 01:24:11 -0700 Subject: sparsemem: record when a section has a valid mem_map We have flags to indicate whether a section actually has a valid mem_map associated with it. This is never set and we rely solely on the present bit to indicate a section is valid. By definition a section is not valid if it has no mem_map and there is a window during init where the present bit is set but there is no mem_map, during which pfn_valid() will return true incorrectly. Use the existing SECTION_HAS_MEM_MAP flag to indicate the presence of a valid mem_map. Switch valid_section{,_nr} and pfn_valid() to this bit. Add a new present_section{,_nr} and pfn_present() interfaces for those users who care to know that a section is going to be valid. [akpm@linux-foundation.org: coding-syle fixes] Signed-off-by: Andy Whitcroft Acked-by: Mel Gorman Cc: Christoph Lameter Cc: "Luck, Tony" Cc: Andi Kleen Cc: "David S. Miller" Cc: Paul Mackerras Cc: Benjamin Herrenschmidt Cc: KAMEZAWA Hiroyuki Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- mm/sparse.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) (limited to 'mm/sparse.c') diff --git a/mm/sparse.c b/mm/sparse.c index e8f36e4796d0..54f3940406cb 100644 --- a/mm/sparse.c +++ b/mm/sparse.c @@ -176,7 +176,7 @@ unsigned long __init node_memmap_size_bytes(int nid, unsigned long start_pfn, if (nid != early_pfn_to_nid(pfn)) continue; - if (pfn_valid(pfn)) + if (pfn_present(pfn)) nr_pages += PAGES_PER_SECTION; } @@ -206,11 +206,12 @@ struct page *sparse_decode_mem_map(unsigned long coded_mem_map, unsigned long pn static int __meminit sparse_init_one_section(struct mem_section *ms, unsigned long pnum, struct page *mem_map) { - if (!valid_section(ms)) + if (!present_section(ms)) return -EINVAL; ms->section_mem_map &= ~SECTION_MAP_MASK; - ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum); + ms->section_mem_map |= sparse_encode_mem_map(mem_map, pnum) | + SECTION_HAS_MEM_MAP; return 1; } @@ -256,7 +257,7 @@ void __init sparse_init(void) struct page *map; for (pnum = 0; pnum < NR_MEM_SECTIONS; pnum++) { - if (!valid_section_nr(pnum)) + if (!present_section_nr(pnum)) continue; map = sparse_early_mem_map_alloc(pnum); -- cgit v1.2.3-58-ga151