From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx> Use a bit in page_type to mark pages which have been allocated through vmalloc. This can be helpful when debugging or analysing crashdumps. Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx> --- include/linux/page-flags.h | 6 ++++++ mm/vmalloc.c | 2 ++ 2 files changed, 8 insertions(+) diff --git a/include/linux/page-flags.h b/include/linux/page-flags.h index d151f590bbc6..8142ab716e90 100644 --- a/include/linux/page-flags.h +++ b/include/linux/page-flags.h @@ -643,6 +643,7 @@ PAGEFLAG_FALSE(DoubleMap) #define PG_buddy 0x00000080 #define PG_balloon 0x00000100 #define PG_kmemcg 0x00000200 +#define PG_vmalloc 0x00000400 #define PageType(page, flag) \ ((page->page_type & (PAGE_TYPE_BASE | flag)) == PAGE_TYPE_BASE) @@ -681,6 +682,11 @@ PAGE_TYPE_OPS(Balloon, balloon) */ PAGE_TYPE_OPS(Kmemcg, kmemcg) +/* + * Pages allocated through vmalloc are tagged with this bit. + */ +PAGE_TYPE_OPS(Vmalloc, vmalloc) + extern bool is_free_buddy_page(struct page *page); __PAGEFLAG(Isolated, isolated, PF_ANY); diff --git a/mm/vmalloc.c b/mm/vmalloc.c index ebff729cc956..3bc0538fc21b 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -1536,6 +1536,7 @@ static void __vunmap(const void *addr, int deallocate_pages) struct page *page = area->pages[i]; BUG_ON(!page); + __ClearPageVmalloc(page); __free_pages(page, 0); } @@ -1705,6 +1706,7 @@ static void *__vmalloc_area_node(struct vm_struct *area, gfp_t gfp_mask, area->nr_pages = i; goto fail; } + __SetPageVmalloc(page); area->pages[i] = page; if (gfpflags_allow_blocking(gfp_mask|highmem_mask)) cond_resched(); -- 2.16.1 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@xxxxxxxxx. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: <a href=mailto:"dont@xxxxxxxxx";> email@xxxxxxxxx </a>
