Martin Schwidefsky abf09bed3c s390/mm: implement software dirty bits ... The s390 architecture is unique in respect to dirty page detection, it uses the change bit in the per-page storage key to track page modifications. All other architectures track dirty bits by means of page table entries. This property of s390 has caused numerous problems in the past, e.g. see git commit ef5d437f71 "mm: fix XFS oops due to dirty pages without buffers on s390". To avoid future issues in regard to per-page dirty bits convert s390 to a fault based software dirty bit detection mechanism. All user page table entries which are marked as clean will be hardware read-only, even if the pte is supposed to be writable. A write by the user process will trigger a protection fault which will cause the user pte to be marked as dirty and the hardware read-only bit is removed. With this change the dirty bit in the storage key is irrelevant for Linux as a host, but the storage key is still required for KVM guests. The effect is that page_test_and_clear_dirty and the related code can be removed. The referenced bit in the storage key is still used by the page_test_and_clear_young primitive to provide page age information. For page cache pages of mappings with mapping_cap_account_dirty there will not be any change in behavior as the dirty bit tracking already uses read-only ptes to control the amount of dirty pages. Only for swap cache pages and pages of mappings without mapping_cap_account_dirty there can be additional protection faults. To avoid an excessive number of additional faults the mk_pte primitive checks for PageDirty if the pgprot value allows for writes and pre-dirties the pte. That avoids all additional faults for tmpfs and shmem pages until these pages are added to the swap cache. Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>		2013-02-14 15:55:23 +01:00
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alpha
arm	highbank fixes for 3.8	2013-02-09 20:55:03 -08:00
arm64	arm64: elf: fix core dumping to match what glibc expects	2013-01-22 17:50:59 +00:00
avr32	avr32: Provide dma_mmap_coherent() and dma_get_sgtable()	2013-01-29 08:11:14 +01:00
blackfin	blackfin: Provide dma_mmap_coherent() and dma_get_sgtable()	2013-01-29 08:11:14 +01:00
c6x	c6x: Provide dummy dma_mmap_coherent() and dma_get_sgtable()	2013-01-29 08:11:14 +01:00
cris	cris: Provide dma_mmap_coherent() and dma_get_sgtable()	2013-01-29 08:11:14 +01:00
frv	frv: Provide dummy dma_mmap_coherent() and dma_get_sgtable()	2013-01-29 08:11:15 +01:00
h8300
hexagon
ia64	ia64: kill thread_matches(), unexport ptrace_check_attach()	2013-01-20 12:26:05 -08:00
m32r
m68k	Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu into akpm	2013-02-12 16:15:39 -08:00
microblaze
mips	MIPS: Function tracer: Fix broken function tracing	2013-01-31 15:28:48 +01:00
mn10300	mn10300: Provide dummy dma_mmap_coherent() and dma_get_sgtable()	2013-01-29 08:27:40 +01:00
openrisc
parisc	parisc: Provide dummy dma_mmap_coherent() and dma_get_sgtable()	2013-01-29 08:27:41 +01:00
powerpc	powerpc/mm: Fix hash computation function	2013-02-04 15:15:08 +11:00
s390	s390/mm: implement software dirty bits	2013-02-14 15:55:23 +01:00
score
sh
sparc
tile	tile: tag some code with #ifdef CONFIG_COMPAT	2013-02-08 13:20:43 -05:00
um
unicore32
x86	x86/mm: Check if PUD is large when validating a kernel address	2013-02-13 10:02:55 +01:00
xtensa	xtensa: Provide dummy dma_mmap_coherent() and dma_get_sgtable()	2013-01-29 08:27:41 +01:00
.gitignore
Kconfig