diff options
author | Olof Johansson <olof@lixom.net> | 2012-11-06 06:48:05 -0800 |
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committer | Olof Johansson <olof@lixom.net> | 2012-11-06 06:48:05 -0800 |
commit | 3b19119b95a52200c8ae3df3aa89c21c9a1a8894 (patch) | |
tree | 3ae74b8a35b3d1f639a68c1690af1c06e14a1571 /mm/rmap.c | |
parent | ccb1cfcb964fa8a8acd58b7783b2e82d7ad7975b (diff) | |
parent | e095c0d122c09efabe7d4136ce77f72c636c4879 (diff) |
Merge tag 'calxeda-ecx-2000' of git://sources.calxeda.com/kernel/linux into next/soc
Support for Calxeda ECX-2000 SOC from Rob Herring
* tag 'calxeda-ecx-2000' of git://sources.calxeda.com/kernel/linux:
ARM: highbank: Add initial ECX-2000 support
ARM: highbank: abstract out SCU usage
ARM: smp_twd: don't warn on no DT node
ARM: dts: Add Calxeda ECX-2000 support
ARM: highbank: enable coherent DMA for xgmac in dts
ARM: highbank: disable unused sdhci and gpio in dts
+ sync to Linux 3.7-rc3
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); /* |