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2009-06-15net: annotate inet_timewait_sock bitfieldsVegard Nossum2-1/+7
The use of bitfields here would lead to false positive warnings with kmemcheck. Silence them. (Additionally, one erroneous comment related to the bitfield was also fixed.) Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15ieee1394/csr1212: fix false positive kmemcheck reportVegard Nossum1-0/+2
kmemcheck reports a use of uninitialized memory here, but it's not a real error. The structure in question has just been allocated, and the whole field is initialized, but it happens in two steps. We fix the false positive by inserting a kmemcheck annotation. Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15ieee1394: annotate bitfieldVegard Nossum1-0/+5
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15net: annotate bitfields in struct inet_sockVegard Nossum1-4/+10
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15net: use kmemcheck bitfields API for skbuffVegard Nossum2-0/+15
Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: introduce bitfield APIVegard Nossum1-0/+50
Add the bitfield API which can be used to annotate bitfields in structs and get rid of false positive reports. According to Al Viro, the syntax we were using (putting #ifdef inside macro arguments) was not valid C. He also suggested using begin/end markers instead, which is what we do now. [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: add opcode self-testing at bootVegard Nossum4-17/+85
We've had some troubles in the past with weird instructions. This patch adds a self-test framework which can be used to verify that a certain set of opcodes are decoded correctly. Of course, the opcodes which are not tested can still give the wrong results. In short, this is just a safeguard to catch unintentional changes in the opcode decoder. It does not mean that errors can't still occur! [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15x86: unify pte_hiddenJeremy Fitzhardinge1-6/+2
Unify and demacro pte_hidden. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15x86: make _PAGE_HIDDEN conditionalJeremy Fitzhardinge1-1/+6
Only _PAGE_HIDDEN when CONFIG_KMEMCHECK is defined, otherwise set it to 0. Allows later cleanups. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: make kconfig accessible for other architecturesPekka Enberg4-88/+94
The Kconfig options of kmemcheck are hidden under arch/x86 which makes porting to other architectures harder. To fix that, move the Kconfig bits to lib/Kconfig.kmemcheck and introduce a CONFIG_HAVE_ARCH_KMEMCHECK config option that architectures can define. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: enable in the x86 KconfigVegard Nossum3-2/+91
let it rip! Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
2009-06-15kmemcheck: add hooks for the page allocatorVegard Nossum8-31/+122
This adds support for tracking the initializedness of memory that was allocated with the page allocator. Highmem requests are not tracked. Cc: Dave Hansen <dave@linux.vnet.ibm.com> Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> [build fix for !CONFIG_KMEMCHECK] Signed-off-by: Ingo Molnar <mingo@elte.hu> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: add hooks for page- and sg-dma-mappingsVegard Nossum1-0/+5
This is needed for page allocator support to prevent false positives when accessing pages which are dma-mapped. [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: don't track page tablesVegard Nossum3-8/+10
As these are allocated using the page allocator, we need to pass __GFP_NOTRACK before we add page allocator support to kmemcheck. Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15crypto: don't track xor test pages with kmemcheckVegard Nossum1-1/+6
The xor tests are run on uninitialized data, because it is doesn't really matter what the underlying data is. Annotate this false- positive warning. Acked-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15slab: add hooks for kmemcheckPekka Enberg1-2/+18
We now have SLAB support for kmemcheck! This means that it doesn't matter whether one chooses SLAB or SLUB, or indeed whether Linus chooses to chuck SLAB or SLUB.. ;-) Cc: Ingo Molnar <mingo@elte.hu> Cc: Christoph Lameter <clameter@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15slub: add hooks for kmemcheckVegard Nossum1-2/+19
Parts of this patch were contributed by Pekka Enberg but merged for atomicity. Cc: Christoph Lameter <clameter@sgi.com> Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
2009-06-15kmemcheck: add DMA hooksVegard Nossum2-0/+18
This patch hooks into the DMA API to prevent the reporting of the false positives that would otherwise be reported when memory is accessed that is also used directly by devices. [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: add mm functionsVegard Nossum7-9/+174
With kmemcheck enabled, the slab allocator needs to do this: 1. Tell kmemcheck to allocate the shadow memory which stores the status of each byte in the allocation proper, e.g. whether it is initialized or uninitialized. 2. Tell kmemcheck which parts of memory that should be marked uninitialized. There are actually a few more states, such as "not yet allocated" and "recently freed". If a slab cache is set up using the SLAB_NOTRACK flag, it will never return memory that can take page faults because of kmemcheck. If a slab cache is NOT set up using the SLAB_NOTRACK flag, callers can still request memory with the __GFP_NOTRACK flag. This does not prevent the page faults from occuring, however, but marks the object in question as being initialized so that no warnings will ever be produced for this object. In addition to (and in contrast to) __GFP_NOTRACK, the __GFP_NOTRACK_FALSE_POSITIVE flag indicates that the allocation should not be tracked _because_ it would produce a false positive. Their values are identical, but need not be so in the future (for example, we could now enable/disable false positives with a config option). Parts of this patch were contributed by Pekka Enberg but merged for atomicity. Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15x86: add hooks for kmemcheckVegard Nossum8-5/+66
The hooks that we modify are: - Page fault handler (to handle kmemcheck faults) - Debug exception handler (to hide pages after single-stepping the instruction that caused the page fault) Also redefine memset() to use the optimized version if kmemcheck is enabled. (Thanks to Pekka Enberg for minimizing the impact on the page fault handler.) As kmemcheck doesn't handle MMX/SSE instructions (yet), we also disable the optimized xor code, and rely instead on the generic C implementation in order to avoid false-positive warnings. Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no> [whitespace fixlet] Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
2009-06-15kmemcheck: use kmemcheck_pte_lookup() instead of open-coding itPekka Enberg1-6/+1
Lets use kmemcheck_pte_lookup() in kmemcheck_fault() instead of open-coding it there. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: move 64-bit ifdef out of kmemcheck_opcode_decode()Pekka Enberg1-2/+7
This patch moves the CONFIG_X86_64 ifdef out of kmemcheck_opcode_decode() by introducing a version of the function that always returns false for CONFIG_X86_32. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: remove multiple ifdef'd definitions of the same global variablePekka Enberg1-3/+5
Multiple ifdef'd definitions of the same global variable is ugly and error-prone. Fix that up. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: make initialization message less confusingPekka Enberg1-1/+1
The "Bugs, beware!" printout during is cute but confuses users that something bad happened so change the text to the more boring "Initialized" message. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-15kmemcheck: remove forward declarations from error.cPekka Enberg1-69/+68
This patch reorders code in error.c so that we can get rid of the forward declarations. Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-13kmemcheck: include module.h to prevent warningsRandy Dunlap1-0/+1
kmemcheck/shadow.c needs to include <linux/module.h> to prevent the following warnings: linux-next-20080724/arch/x86/mm/kmemcheck/shadow.c:64: warning : data definition has no type or storage class linux-next-20080724/arch/x86/mm/kmemcheck/shadow.c:64: warning : type defaults to 'int' in declaration of 'EXPORT_SYMBOL_GPL' linux-next-20080724/arch/x86/mm/kmemcheck/shadow.c:64: warning : parameter names (without types) in function declaration Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Cc: vegardno@ifi.uio.no Cc: penberg@cs.helsinki.fi Cc: akpm <akpm@linux-foundation.org> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-13kmemcheck: add the kmemcheck coreVegard Nossum19-2/+1304
General description: kmemcheck is a patch to the linux kernel that detects use of uninitialized memory. It does this by trapping every read and write to memory that was allocated dynamically (e.g. using kmalloc()). If a memory address is read that has not previously been written to, a message is printed to the kernel log. Thanks to Andi Kleen for the set_memory_4k() solution. Andrew Morton suggested documenting the shadow member of struct page. Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> [export kmemcheck_mark_initialized] [build fix for setup_max_cpus] Signed-off-by: Ingo Molnar <mingo@elte.hu> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegardno@ifi.uio.no>
2009-06-13kmemcheck: add the kmemcheck documentationVegard Nossum1-0/+773
Thanks to Sitsofe Wheeler, Randy Dunlap, and Jonathan Corbet for providing input and feedback on this! Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-13kmemcheck: add Vegard and Pekka to MAINTAINERSPekka Enberg1-6/+14
Acked-by: Vegard Nossum <vegardno@ifi.uio.no> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> Signed-off-by: Ingo Molnar <mingo@elte.hu>
2009-06-13tasklets: new tasklet scheduling functionVegard Nossum2-0/+25
Rationale: kmemcheck needs to be able to schedule a tasklet without touching any dynamically allocated memory _at_ _all_ (since that would lead to a recursive page fault). This tasklet is used for writing the error reports to the kernel log. The new scheduling function avoids touching any other tasklets by inserting the new tasklist as the head of the "tasklet_hi" list instead of on the tail. Also don't wake up the softirq thread lest the scheduler access some tracked memory and we go down with a recursive page fault. In this case, we'd better just wait for the maximum time of 1/HZ for the message to appear. Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-13slab: move struct kmem_cache to headersPekka Enberg2-81/+81
Move the SLAB struct kmem_cache definition to <linux/slab_def.h> like with SLUB so kmemcheck can access ->ctor and ->flags. Cc: Ingo Molnar <mingo@elte.hu> Cc: Christoph Lameter <clameter@sgi.com> Cc: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Pekka Enberg <penberg@cs.helsinki.fi> [rebased for mainline inclusion] Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-12stacktrace: add forward-declaration struct task_structVegard Nossum1-0/+2
This is needed if the header is to be free-standing. Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-12x86: add save_stack_trace_bp() for tracing from a specific stack frameVegard Nossum2-0/+8
This will help kmemcheck (and possibly other debugging tools) since we can now simply pass regs->bp to the stack tracer instead of specifying the number of stack frames to skip, which is unreliable if gcc decides to inline functions, etc. Note that this makes the API incomplete for other architectures, but I expect that those can be updated lazily, e.g. when they need it. Cc: Arjan van de Ven <arjan@linux.intel.com> Signed-off-by: Vegard Nossum <vegard.nossum@gmail.com>
2009-06-11block: fix kernel-doc in recent block/ changesRandy Dunlap2-13/+14
Fix kernel-doc warnings in recently changed block/ source code. Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6Linus Torvalds147-1834/+1707
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (87 commits) nilfs2: get rid of bd_mount_sem use from nilfs nilfs2: correct exclusion control in nilfs_remount function nilfs2: simplify remaining sget() use nilfs2: get rid of sget use for checking if current mount is present nilfs2: get rid of sget use for acquiring nilfs object nilfs2: remove meaningless EBUSY case from nilfs_get_sb function remove the call to ->write_super in __sync_filesystem nilfs2: call nilfs2_write_super from nilfs2_sync_fs jffs2: call jffs2_write_super from jffs2_sync_fs ufs: add ->sync_fs sysv: add ->sync_fs hfsplus: add ->sync_fs hfs: add ->sync_fs fat: add ->sync_fs ext2: add ->sync_fs exofs: add ->sync_fs bfs: add ->sync_fs affs: add ->sync_fs sanitize ->fsync() for affs repair bfs_write_inode(), switch bfs to simple_fsync() ...
2009-06-11Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommuLinus Torvalds23-187/+178
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/gerg/m68knommu: m68knommu: remove unecessary include of thread_info.h in entry.S m68knommu: enumerate INIT_THREAD fields properly headers_check fix: m68k, swab.h arch/m68knommu: Convert #ifdef DEBUG printk(KERN_DEBUG to pr_debug( m68knommu: remove obsolete reset code m68knommu: move CPU reset code for the 5272 ColdFire into its platform code m68knommu: move CPU reset code for the 528x ColdFire into its platform code m68knommu: move CPU reset code for the 527x ColdFire into its platform code m68knommu: move CPU reset code for the 523x ColdFire into its platform code m68knommu: move CPU reset code for the 520x ColdFire into its platform code m68knommu: add CPU reset code for the 532x ColdFire m68knommu: add CPU reset code for the 5249 ColdFire m68knommu: add CPU reset code for the 5206e ColdFire m68knommu: add CPU reset code for the 5206 ColdFire m68knommu: add CPU reset code for the 5407 ColdFire m68knommu: add CPU reset code for the 5307 ColdFire m68knommu: merge system reset for code ColdFire 523x family m68knommu: fix system reset for ColdFire 527x family
2009-06-11kvm: remove the duplicated cpumask_clearYinghai Lu1-1/+0
zalloc_cpumask_var already cleared it. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11x86: use zalloc_cpumask_var in arch_early_irq_initYinghai Lu1-2/+2
So we make sure MAXSMP gets a cleared cpumask Signed-off-by: Yinghai Lu <yinghai@kernel.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11perfcounters: remove powerpc definitions of perf_counter_do_pendingStephen Rothwell2-3/+1
Commit 925d519ab82b6dd7aca9420d809ee83819c08db2 ("perf_counter: unify and fix delayed counter wakeup") added global definitions. Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au> Acked-by: Paul Mackerras <paulus@samba.org> Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-06-11nilfs2: get rid of bd_mount_sem use from nilfsRyusuke Konishi4-9/+12
This will remove every bd_mount_sem use in nilfs. The intended exclusion control was replaced by the previous patch ("nilfs2: correct exclusion control in nilfs_remount function") for nilfs_remount(), and this patch will replace remains with a new mutex that this inserts in nilfs object. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Christoph Hellwig <hch@infradead.org> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11nilfs2: correct exclusion control in nilfs_remount functionRyusuke Konishi3-31/+33
nilfs_remount() changes mount state of a superblock instance. Even though nilfs accesses other superblock instances during mount or remount, the mount state was not properly protected in nilfs_remount(). Moreover, nilfs_remount() has a lock order reversal problem; nilfs_get_sb() holds: 1. bdev->bd_mount_sem 2. sb->s_umount (sget acquires) and nilfs_remount() holds: 1. sb->s_umount (locked by the caller in vfs) 2. bdev->bd_mount_sem To avoid these problems, this patch divides a semaphore protecting super block instances from nilfs->ns_sem, and applies it to the mount state protection in nilfs_remount(). With this change, bd_mount_sem use is removed from nilfs_remount() and the lock order reversal will be resolved. And the new rw-semaphore, nilfs->ns_super_sem will properly protect the mount state except the modification from nilfs_error function. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11nilfs2: simplify remaining sget() useRyusuke Konishi4-25/+75
This simplifies the test function passed on the remaining sget() callsite in nilfs. Instead of checking mount type (i.e. ro-mount/rw-mount/snapshot mount) in the test function passed to sget(), this patch first looks up the nilfs_sb_info struct which the given mount type matches, and then acquires the super block instance holding the nilfs_sb_info. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11nilfs2: get rid of sget use for checking if current mount is presentRyusuke Konishi2-60/+35
This stops using sget() for checking if an r/w-mount or an r/o-mount exists on the device. This elimination uses a back pointer to the current mount added to nilfs object. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11nilfs2: get rid of sget use for acquiring nilfs objectRyusuke Konishi3-65/+76
This will change the way to obtain nilfs object in nilfs_get_sb() function. Previously, a preliminary sget() call was performed, and the nilfs object was acquired from a super block instance found by the sget() call. This patch, instead, instroduces a new dedicated function find_or_create_nilfs(); as the name implies, the function finds an existent nilfs object from a global list or creates a new one if no object is found on the device. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11nilfs2: remove meaningless EBUSY case from nilfs_get_sb functionRyusuke Konishi1-2/+0
The following EBUSY case in nilfs_get_sb() is meaningless. Indeed, this error code is never returned to the caller. if (!s->s_root) { ... } else if (!(s->s_flags & MS_RDONLY)) { err = -EBUSY; } This simply removes the else case. Signed-off-by: Ryusuke Konishi <konishi.ryusuke@lab.ntt.co.jp> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11remove the call to ->write_super in __sync_filesystemChristoph Hellwig1-2/+0
Now that all filesystems provide ->sync_fs methods we can change __sync_filesystem to only call ->sync_fs. This gives us a clear separation between periodic writeouts which are driven by ->write_super and data integrity syncs that go through ->sync_fs. (modulo file_fsync which is also going away) Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11nilfs2: call nilfs2_write_super from nilfs2_sync_fsChristoph Hellwig1-0/+2
The call to ->write_super from __sync_filesystem will go away, so make sure nilfs2 performs the same actions from inside ->sync_fs. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11jffs2: call jffs2_write_super from jffs2_sync_fsChristoph Hellwig1-0/+2
The call to ->write_super from __sync_filesystem will go away, so make sure jffs2 performs the same actions from inside ->sync_fs. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11ufs: add ->sync_fsChristoph Hellwig1-10/+22
Add a ->sync_fs method for data integrity syncs, and reimplement ->write_super ontop of it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-11sysv: add ->sync_fsChristoph Hellwig1-6/+13
Add a ->sync_fs method for data integrity syncs, and reimplement ->write_super ontop of it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>