diff options
author | Arnd Bergmann <arnd@arndb.de> | 2012-11-15 17:27:43 +0100 |
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committer | Arnd Bergmann <arnd@arndb.de> | 2012-11-15 17:27:43 +0100 |
commit | 12480c2e53d355223cf6884ed1f56e6ac9b7c21f (patch) | |
tree | c244c5b4f265dc38f7658fbe5714ba2c402aef28 /mm/rmap.c | |
parent | 6c8e94a57c30e31d0807f038b4f98b659fd67776 (diff) | |
parent | 936407358759adb302df93ab61fa68141897270c (diff) |
Merge tag 'omap-for-v3.8/fixes-non-critical-v4-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap into next/fixes-non-critical
From Tony Lindgren <tony@atomide.com>:
Non critical omap fixes that were not considered urgent
for the -rc cycle.
* tag 'omap-for-v3.8/fixes-non-critical-v4-signed' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind/linux-omap: (645 commits)
ARM: OMAP4: PM: fix errata handling when CONFIG_PM=n
ARM: OMAP4: retrigger localtimers after re-enabling gic
ARM: OMAP4460: Workaround for ROM bug because of CA9 r2pX GIC control register change.
ARM: OMAP4: PM: add errata support
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
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 7df7984d476c..2ee1ef0f317b 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); /* |