Instead of always splitting the file offset into 32-bit 'high' and 'low'
parts, just split them into the largest natural word-size - which in C
terms is 'unsigned long'.

This allows 64-bit architectures to avoid the unnecessary 32-bit
shifting and masking for native format (while the compat interfaces will
obviously always have to do it).

This also changes the order of 'high' and 'low' to be "low first".  Why?
Because when we have it like this, the 64-bit system calls now don't use
the "pos_high" argument at all, and it makes more sense for the native
system call to simply match the user-mode prototype.

This results in a much more natural calling convention, and allows the
compiler to generate much more straightforward code.  On x86-64, we now
generate

        testq   %rcx, %rcx      # pos_l
        js      .L122   #,
        movq    %rcx, -48(%rbp) # pos_l, pos

from the C source

        loff_t pos = pos_from_hilo(pos_h, pos_l);
	...
        if (pos < 0)
                return -EINVAL;

and the 'pos_h' register isn't even touched.  It used to generate code
like

        mov     %r8d, %r8d      # pos_low, pos_low
        salq    $32, %rcx       #, tmp71
        movq    %r8, %rax       # pos_low, pos.386
        orq     %rcx, %rax      # tmp71, pos.386
        js      .L122   #,
        movq    %rax, -48(%rbp) # pos.386, pos

which isn't _that_ horrible, but it does show how the natural word size
is just a more sensible interface (same arguments will hold in the user
level glibc wrapper function, of course, so the kernel side is just half
of the equation!)

Note: in all cases the user code wrapper can again be the same. You can
just do

	#define HALF_BITS (sizeof(unsigned long)*4)
	__syscall(PWRITEV, fd, iov, count, offset, (offset >> HALF_BITS) >> HALF_BITS);

or something like that.  That way the user mode wrapper will also be
nicely passing in a zero (it won't actually have to do the shifts, the
compiler will understand what is going on) for the last argument.

And that is a good idea, even if nobody will necessarily ever care: if
we ever do move to a 128-bit lloff_t, this particular system call might
be left alone.  Of course, that will be the least of our worries if we
really ever need to care, so this may not be worth really caring about.

[ Fixed for lost 'loff_t' cast noticed by Andrew Morton ]
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: linux-api@vger.kernel.org
Cc: linux-arch@vger.kernel.org
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Ralf Baechle <ralf@linux-mips.org>>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

Merge branch 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'x86-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  x86, mtrr: remove debug message
  x86: disable stack-protector for __restore_processor_state()
  x86: fix is_io_mapping_possible() build warning on i386 allnoconfig
  x86, setup: compile with -DDISABLE_BRANCH_PROFILING
  x86/dma: unify definition of pci_unmap_addr* and pci_unmap_len macros
  x86, mm: fix misuse of debug_kmap_atomic
  x86: remove duplicated code with pcpu_need_numa()
  x86,percpu: fix inverted NUMA test in setup_pcpu_remap()
  x86: signal: check sas_ss_size instead of sas_ss_flags()

Merge branch 'core-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'core-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  ptrace: remove a useless goto

Merge branch 'stacktrace-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

* 'stacktrace-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  symbols, stacktrace: look up init symbols after module symbols

* 'rcu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  rcu: rcu_barrier VS cpu_hotplug: Ensure callbacks in dead cpu are migrated to online cpu

* 'ipi-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  s390: remove arch specific smp_send_stop()
  panic: clean up kernel/panic.c
  panic, smp: provide smp_send_stop() wrapper on UP too
  panic: decrease oops_in_progress only after having done the panic
  generic-ipi: eliminate WARN_ON()s during oops/panic
  generic-ipi: cleanups
  generic-ipi: remove CSD_FLAG_WAIT
  generic-ipi: remove kmalloc()
  generic IPI: simplify barriers and locking

* 'locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip:
  locking: rename trace_softirq_[enter|exit] => lockdep_softirq_[enter|exit]
  lockdep: remove duplicate CONFIG_DEBUG_LOCKDEP definitions
  lockdep: require framepointers for x86
  lockdep: remove extra "irq" string
  lockdep: fix incorrect state name

The MTRR code grew a new debug message which triggers commonly:

[   40.142276]   get_mtrr: cpu0 reg00 base=0000000000 size=0000080000 write-back
[   40.142280]   get_mtrr: cpu0 reg01 base=0000080000 size=0000040000 write-back
[   40.142284]   get_mtrr: cpu0 reg02 base=0000100000 size=0000040000 write-back
[   40.142311]   get_mtrr: cpu0 reg00 base=0000000000 size=0000080000 write-back
[   40.142314]   get_mtrr: cpu0 reg01 base=0000080000 size=0000040000 write-back
[   40.142317]   get_mtrr: cpu0 reg02 base=0000100000 size=0000040000 write-back

Remove this annoyance.
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: allow private mappings of "direct_io" files
  fuse: allow kernel to access "direct_io" files

Bring the devices.txt back into some relationship with reality. Update the
documentation a bit.
Signed-off-by: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid:
  HID: remove compat stuff
  HID: constify arrays of struct apple_key_translation
  HID: add support for Kye/Genius Ergo 525V
  HID: Support Apple mini aluminum keyboard
  HID: support for Kensington slimblade device
  HID: DragonRise game controller force feedback driver
  HID: add support for another version of 0e8f:0003 device in hid-pl
  HID: fix race between usb_register_dev() and hiddev_open()
  HID: bring back possibility to specify vid/pid ignore on module load
  HID: make HID_DEBUG defaults consistent
  HID: autosuspend -- fix lockup of hid on reset
  HID: hid_reset_resume() needs to be defined only when CONFIG_PM is set
  HID: fix USB HID devices after STD with autosuspend
  HID: do not try to compile PM code with CONFIG_PM unset
  HID: autosuspend support for USB HID

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (28 commits)
  trivial: Update my email address
  trivial: NULL noise: drivers/mtd/tests/mtd_*test.c
  trivial: NULL noise: drivers/media/dvb/frontends/drx397xD_fw.h
  trivial: Fix misspelling of "Celsius".
  trivial: remove unused variable 'path' in alloc_file()
  trivial: fix a pdlfush -> pdflush typo in comment
  trivial: jbd header comment typo fix for JBD_PARANOID_IOFAIL
  trivial: wusb: Storage class should be before const qualifier
  trivial: drivers/char/bsr.c: Storage class should be before const qualifier
  trivial: h8300: Storage class should be before const qualifier
  trivial: fix where cgroup documentation is not correctly referred to
  trivial: Give the right path in Documentation example
  trivial: MTD: remove EOL from MODULE_DESCRIPTION
  trivial: Fix typo in bio_split()'s documentation
  trivial: PWM: fix of #endif comment
  trivial: fix typos/grammar errors in Kconfig texts
  trivial: Fix misspelling of firmware
  trivial: cgroups: documentation typo and spelling corrections
  trivial: Update contact info for Jochen Hein
  trivial: fix typo "resgister" -> "register"
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/czankel/xtensa-2.6: (21 commits)
  xtensa: we don't need to include asm/io.h
  xtensa: only build platform or variant if they contain a Makefile
  xtensa: make startup code discardable
  xtensa: ccount clocksource
  xtensa: remove platform rtc hooks
  xtensa: use generic sched_clock()
  xtensa: platform: s6105
  xtensa: let platform override KERNELOFFSET
  xtensa: s6000 variant
  xtensa: s6000 variant core definitions
  xtensa: variant irq set callbacks
  xtensa: variant-specific code
  xtensa: nommu support
  xtensa: add flat support
  xtensa: enforce slab alignment to maximum register width
  xtensa: cope with ram beginning at higher addresses
  xtensa: don't make bootmem bitmap larger than required
  xtensa: fix init_bootmem_node() argument order
  xtensa: use correct stack pointer for stack traces
  xtensa: beat Kconfig into shape
  ...

* git://git.kernel.org/pub/scm/linux/kernel/git/mason/btrfs-unstable:
  Btrfs: BUG to BUG_ON changes
  Btrfs: remove dead code
  Btrfs: remove dead code
  Btrfs: fix typos in comments
  Btrfs: remove unused ftrace include
  Btrfs: fix __ucmpdi2 compile bug on 32 bit builds
  Btrfs: free inode struct when btrfs_new_inode fails
  Btrfs: fix race in worker_loop
  Btrfs: add flushoncommit mount option
  Btrfs: notreelog mount option
  Btrfs: introduce btrfs_show_options
  Btrfs: rework allocation clustering
  Btrfs: Optimize locking in btrfs_next_leaf()
  Btrfs: break up btrfs_search_slot into smaller pieces
  Btrfs: kill the pinned_mutex
  Btrfs: kill the block group alloc mutex
  Btrfs: clean up find_free_extent
  Btrfs: free space cache cleanups
  Btrfs: unplug in the async bio submission threads
  Btrfs: keep processing bios for a given bdev if our proc is batching

pci mmap code was doing memtype reserve for a while now. Recently we
added memtype tracking in remap_pfn_range, and pci code indirectly calls
remap_pfn_range. So, we don't need seperate tracking in pci code
anymore. Which means a patch that removes ~50 lines of code :-).

Also, recently we found out that the pci tracking is not working as we expect
it to work in some cases. Specifically, userlevel X mmap of pci, with some
recent version of X, is having a problem with vm_page_prot getting reset.
The pci tracking uses vm_page_prot to pass on the protection type from parent
to child during fork.
a) Parent does a pci mmap
b) We look at PAT and get either UC_MINUS or WC mapping for parent
c) Store that mapping type in vma vm_page_prot for future use
d) This thread does a fork
e) Fork results in mmap_ops ->open for the child process
f) We get the vm_page_prot from vma and reserve that type for the child process

But, between c) and e) above, the vma vm_page_prot is getting reset to zero.
This results in PAT reserve failing at the time of fork as in here.
http://marc.info/?l=linux-kernel&m=123858163103240&w=2

This cleanup makes the above problem go away as we do not depend on
vm_page_prot in our PAT code anymore.
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mfasheh/ocfs2: (32 commits)
  ocfs2: recover orphans in offline slots during recovery and mount
  ocfs2: Pagecache usage optimization on ocfs2
  ocfs2: fix rare stale inode errors when exporting via nfs
  ocfs2/dlm: Tweak mle_state output
  ocfs2/dlm: Do not purge lockres that is being migrated dlm_purge_lockres()
  ocfs2/dlm: Remove struct dlm_lock_name in struct dlm_master_list_entry
  ocfs2/dlm: Show the number of lockres/mles in dlm_state
  ocfs2/dlm: dlm_set_lockres_owner() and dlm_change_lockres_owner() inlined
  ocfs2/dlm: Improve lockres counts
  ocfs2/dlm: Track number of mles
  ocfs2/dlm: Indent dlm_cleanup_master_list()
  ocfs2/dlm: Activate dlm->master_hash for master list entries
  ocfs2/dlm: Create and destroy the dlm->master_hash
  ocfs2/dlm: Refactor dlm_clean_master_list()
  ocfs2/dlm: Clean up struct dlm_lock_name
  ocfs2/dlm: Encapsulate adding and removing of mle from dlm->master_list
  ocfs2: Optimize inode group allocation by recording last used group.
  ocfs2: Allocate inode groups from global_bitmap.
  ocfs2: Optimize inode allocation by remembering last group
  ocfs2: fix leaf start calculation in ocfs2_dx_dir_rebalance()
  ...

* 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx:
  dma: Add SoF and EoF debugging to ipu_idmac.c, minor cleanup
  dw_dmac: add cyclic API to DW DMA driver
  dmaengine: Add privatecnt to revert DMA_PRIVATE property
  dmatest: add dma interrupts and callbacks
  dmatest: add xor test
  dmaengine: allow dma support for async_tx to be toggled
  async_tx: provide __async_inline for HAS_DMA=n archs
  dmaengine: kill some unused headers
  dmaengine: initialize tx_list in dma_async_tx_descriptor_init
  dma: i.MX31 IPU DMA robustness improvements
  dma: improve section assignment in i.MX31 IPU DMA driver
  dma: ipu_idmac driver cosmetic clean-up
  dmaengine: fail device registration if channel registration fails

During recovery, a node recovers orphans in it's slot and the dead node(s). But
if the dead nodes were holding orphans in offline slots, they will be left
unrecovered.

If the dead node is the last one to die and is holding orphans in other slots
and is the first one to mount, then it only recovers it's own slot, which
leaves orphans in offline slots.

This patch queues complete_recovery to clean orphans for all offline slots
during mount and node recovery.
Signed-off-by: Srinivas Eeda <srinivas.eeda@oracle.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

A page can have multiple buffers and even if a page is not uptodate, some buffers
can be uptodate on pagesize != blocksize environment.
This aops checks that all buffers which correspond to a part of a file
that we want to read are uptodate. If so, we do not have to issue actual
read IO to HDD even if a page is not uptodate because the portion we
want to read are uptodate.
"block_is_partially_uptodate" function is already used by ext2/3/4.
With the following patch random read/write mixed workloads or random read after
random write workloads can be optimized and we can get performance improvement.
Signed-off-by: Hisashi Hifumi <hifumi.hisashi@oss.ntt.co.jp>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

For nfs exporting, ocfs2_get_dentry() returns the dentry for fh.
ocfs2_get_dentry() may read from disk when the inode is not in memory,
without any cross cluster lock. this leads to the file system loading a
stale inode.

This patch fixes above problem.

Solution is that in case of inode is not in memory, we get the cluster
lock(PR) of alloc inode where the inode in question is allocated from (this
causes node on which deletion is done sync the alloc inode) before reading
out the inode itsself. then we check the bitmap in the group (the inode in
question allcated from) to see if the bit is clear. if it's clear then it's
stale. if the bit is set, we then check generation as the existing code
does.

We have to read out the inode in question from disk first to know its alloc
slot and allot bit. And if its not stale we read it out using ocfs2_iget().
The second read should then be from cache.

And also we have to add a per superblock nfs_sync_lock to cover the lock for
alloc inode and that for inode in question. this is because ocfs2_get_dentry()
and ocfs2_delete_inode() lock on them in reverse order. nfs_sync_lock is locked
in EX mode in ocfs2_get_dentry() and in PR mode in ocfs2_delete_inode(). so
that mutliple ocfs2_delete_inode() can run concurrently in normal case.

[mfasheh@suse.com: build warning fixes and comment cleanups]
Signed-off-by: Wengang Wang <wen.gang.wang@oracle.com>
Acked-by: Joel Becker <joel.becker@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

The debugfs file, mle_state, now prints the number of largest number of mles
in one hash link.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch attempts to fix a fine race between purging and migration.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch removes struct dlm_lock_name and adds the entries directly
to struct dlm_master_list_entry. Under the new scheme, both mles that
are backed by a lockres or not, will have the name populated in mle->mname.
This allows us to get rid of code that was figuring out the location of
the mle name.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch shows the number of lockres' and mles in the debugfs file, dlm_state.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch inlines dlm_set_lockres_owner() and dlm_change_lockres_owner().
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch replaces the lockres counts that tracked the number number of
locally and remotely mastered lockres' with a current and total count. The
total count is the number of lockres' that have been created since the dlm
domain was created.

The number of locally and remotely mastered counts can be computed using
the locking_state output.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

The lifetime of a mle is limited to the duration of the lockres mastery
process. While typically this lifetime is fairly short, we have noticed
the number of mles explode under certain circumstances. This patch tracks
the number of each different types of mles and should help us determine
how best to speed up the mastery process.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

The previous patch explicitly did not indent dlm_cleanup_master_list()
so as to make the patch readable. This patch properly indents the
function.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

With this patch, the mles are stored in a hash and not a simple list.
This should improve the mle lookup time when the number of outstanding
masteries is large.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch adds code to create and destroy the dlm->master_hash.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch refactors dlm_clean_master_list() so as to make it
easier to convert the mle list to a hash.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

For master mle, the name it stored in the attached lockres in struct qstr.
For block and migration mle, the name is stored inline in struct dlm_lock_name.
This patch attempts to make struct dlm_lock_name look like a struct qstr. While
we could use struct qstr, we don't because we want to avoid having to malloc
and free the lockname string as the mle's lifetime is fairly short.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

This patch encapsulates adding and removing of the mle from the
dlm->master_list. This patch is part of the series of patches that
converts the mle list to a mle hash.
Signed-off-by: Sunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

In ocfs2, the block group search looks for the "emptiest" group
to allocate from. So if the allocator has many equally(or almost
equally) empty groups, new block group will tend to get spread
out amongst them.

So we add osb_inode_alloc_group in ocfs2_super to record the last
used inode allocation group.
For more details, please see
http://oss.oracle.com/osswiki/OCFS2/DesignDocs/InodeAllocationStrategy.

I have done some basic test and the results are a ten times improvement on
some cold-cache stat workloads.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

Inode groups used to be allocated from local alloc file,
but since we want all inodes to be contiguous enough, we
will try to allocate them directly from global_bitmap.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

In ocfs2, the inode block search looks for the "emptiest" inode
group to allocate from. So if an inode alloc file has many equally
(or almost equally) empty groups, new inodes will tend to get
spread out amongst them, which in turn can put them all over the
disk. This is undesirable because directory operations on conceptually
"nearby" inodes force a large number of seeks.

So we add ip_last_used_group in core directory inodes which records
the last used allocation group. Another field named ip_last_used_slot
is also added in case inode stealing happens. When claiming new inode,
we passed in directory's inode so that the allocation can use this
information.
For more details, please see
http://oss.oracle.com/osswiki/OCFS2/DesignDocs/InodeAllocationStrategy.
Signed-off-by: Tao Ma <tao.ma@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

ocfs2_dx_dir_rebalance() is passed the block offset of a dx leaf which needs
rebalancing. Since we rebalance an entire cluster at a time however, this
function needs to calculate the beginning of that cluster, in blocks. The
calculation was wrong, which would result in a read of non-leaf blocks. Fix
the calculation by adding ocfs2_block_to_cluster_start() which is a more
straight-forward way of determining this.
Reported-by: Tristan Ye <tristan.ye@oracle.com>
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

ocfs2_empty_dir() is far more expensive than checking link count. Since both
need to be checked at the same time, we can improve performance by checking
link count first.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>

Since the disk format is finalized, we can set this feature bit in the
supported mask.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>
Acked-by: Joel Becker <Joel.Becker@oracle.com>

This little bit of extra accounting speeds up ocfs2_empty_dir()
dramatically by allowing us to short-circuit the full directory scan.
Signed-off-by: Mark Fasheh <mfasheh@suse.com>