diff options
| author | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-29 08:46:28 -0700 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2012-10-29 08:46:28 -0700 |
| commit | 94b086b243e112030b815b76e61de6523e6fc700 (patch) | |
| tree | 3c7f2308e7e5afdb276a858c4960754168a92d8c /mm/rmap.c | |
| parent | 967857dfd990081f6702daebc6c9bc6f4ba7a39e (diff) | |
| parent | 8f0d8163b50e01f398b14bcd4dc039ac5ab18d64 (diff) | |
Merge 3.7-rc3 into driver-core-next
This pulls in the various driver core changes that were in 3.7-rc3 into the
driver-core-next branch.
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'mm/rmap.c')
| -rw-r--r-- | mm/rmap.c | 20 |
1 files changed, 15 insertions, 5 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index 7df7984d476..2ee1ef0f317 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -56,6 +56,7 @@ #include <linux/mmu_notifier.h> #include <linux/migrate.h> #include <linux/hugetlb.h> +#include <linux/backing-dev.h> #include <asm/tlbflush.h> @@ -926,11 +927,8 @@ int page_mkclean(struct page *page) if (page_mapped(page)) { struct address_space *mapping = page_mapping(page); - if (mapping) { + if (mapping) ret = page_mkclean_file(mapping, page); - if (page_test_and_clear_dirty(page_to_pfn(page), 1)) - ret = 1; - } } return ret; @@ -1116,6 +1114,7 @@ void page_add_file_rmap(struct page *page) */ void page_remove_rmap(struct page *page) { + struct address_space *mapping = page_mapping(page); bool anon = PageAnon(page); bool locked; unsigned long flags; @@ -1138,8 +1137,19 @@ void page_remove_rmap(struct page *page) * this if the page is anon, so about to be freed; but perhaps * not if it's in swapcache - there might be another pte slot * containing the swap entry, but page not yet written to swap. + * + * And we can skip it on file pages, so long as the filesystem + * participates in dirty tracking; but need to catch shm and tmpfs + * and ramfs pages which have been modified since creation by read + * fault. + * + * Note that mapping must be decided above, before decrementing + * mapcount (which luckily provides a barrier): once page is unmapped, + * it could be truncated and page->mapping reset to NULL at any moment. + * Note also that we are relying on page_mapping(page) to set mapping + * to &swapper_space when PageSwapCache(page). */ - if ((!anon || PageSwapCache(page)) && + if (mapping && !mapping_cap_account_dirty(mapping) && page_test_and_clear_dirty(page_to_pfn(page), 1)) set_page_dirty(page); /* |