In xfs_ialloc we just want to set all timestamps to the current time. We
don't need to mark the inode dirty like xfs_ichgtime does, and we don't
need nor want the opimizations in xfs_ichgtime that I will introduce in
the next patch.

So just opencode the timestamp update in xfs_ialloc, and remove the new
unused XFS_ICHGTIME_ACC case in xfs_ichgtime.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31825a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Now that all users of the sema_t are gone from XFS we can finally kill it.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31823a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Use the new completion flush code to implement the dquot flush lock.
Removes one of the final users of semaphores in the XFS code base.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31822a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Use the new completion flush code to implement the inode flush lock.
Removes one of the final users of semaphores in the XFS code base.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31817a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

XFS object flushing doesn't quite match existing completion semantics.  It
mixed exclusive access with completion.  That is, we need to mark an object as
being flushed before flushing it to disk, and then block any other attempt to
flush it until the completion occurs.  We do this but adding an extra count to
the completion before we start using them.  However, we still need to
determine if there is a completion in progress, and allow no-blocking attempts
fo completions to decrement the count.

To do this we introduce:

int try_wait_for_completion(struct completion *x)
	returns a failure status if done == 0, otherwise decrements done
	to zero and returns a "started" status. This is provided
	to allow counted completions to begin safely while holding
	object locks in inverted order.

int completion_done(struct completion *x)
	returns 1 if there is no waiter, 0 if there is a waiter
	(i.e. a completion in progress).

This replaces the use of semaphores for providing this exclusion
and completion mechanism.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31816a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

The xfs_buf_t b_iodonesema is really just a semaphore that wants to be a
completion. Change it to a completion and remove the last user of the
sema_t from XFS.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31815a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

A lot of code has been converted away from semaphores, but there are still
comments that reference semaphore behaviour. The log code is the worst
offender. Update the comments to reflect what the code really does now.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31814a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31813a
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

SGI-PV: 957103

SGI-Modid: xfs-linux-melb:xfs-kern:31804a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

The alloc and inobt btree use the same agbp/agno pair in the btree_cur
union. Make them use the same bc_private.a union member so that code for
these two short form btree implementations can be shared.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31788a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Remove unneeded xfs_btree_get_block forward declaration. Move
xfs_btree_firstrec next to xfs_btree_lastrec.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31787a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Sanitize setting up the Linux indode.

Setting up the xfs_inode <-> inode link is opencoded in xfs_iget_core now
because that's the only place it needs to be done, xfs_initialize_vnode is
renamed to xfs_setup_inode and loses all superflous paramaters. The check
for I_NEW is removed because it always is true and the di_mode check moves
into xfs_iget_core because it's only needed there.

xfs_set_inodeops and xfs_revalidate_inode are merged into xfs_setup_inode
and the whole things is moved into xfs_iops.c where it belongs.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31782a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

All remaining bhv_vnode_t instance are in code that's more or less Linux
specific. (Well, for xfs_acl.c that could be argued, but that code is on
the removal list, too). So just do an s/bhv_vnode_t/struct inode/ over the
whole tree. We can clean up variable naming and some useless helpers
later.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31781a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

In various places we can just move a VFS_I call into the argument list of
called functions/macros instead of having a local bhv_vnode_t.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31776a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

When multiple inodes are locked in XFS it happens in order of the inode
number, with the everything but the first inode trylocked if any of the
previous inodes is in the AIL.

Except for the sorting of the inodes this logic is implemented in
xfs_lock_inodes, but also partially duplicated in xfs_lock_dir_and_entry
in a particularly stupid way adds a lock roundtrip if the inode ordering
is not optimal.

This patch adds a new helper xfs_lock_two_inodes that takes two inodes and
locks them in the most optimal way according to the above locking protocol
and uses it for all places that want to lock two inodes.

The only caller of xfs_lock_inodes is xfs_rename which might lock up to
four inodes.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31772a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

All the error injection is already enabled through ifdef DEBUG, so kill
the never set second cpp symbol to activate it without the rest of the
debugging infrastructure.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31771a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Now that all direct calls to VN_HOLD/VN_RELE are gone we can implement
IHOLD/IRELE directly.

For the IHOLD case also replace igrab with a direct increment of i_count
because we are guaranteed to already have a live and referenced inode by
the VFS. Also remove the vn_hold statistic because it's been rather
meaningless for some time with most references done by other callers.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31764a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Use IHOLD(ip) instead of VN_HOLD(VFS_I(ip)).

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31765a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

All the ACL routines are called from inode operations which are guaranteed
to have a referenced inode by the VFS, so there's no need for the ACL code
to grab another temporary one.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31763a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

bhv_vnode_t is just a typedef for struct inode, so there's
no need for a helper to convert between the two.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31761a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

bhv_vnode_t is just a typedef for struct inode, so there's
no need for a helper to convert between the two.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31760a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31758a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Looks like somehow xfs got missed in the conversion that took place in
e231c2ee, "Convert ERR_PTR(PTR_ERR(p))
instances to ERR_CAST(p)
<http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit
diff;h=e231c2ee>"

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31757a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Acked-by: David Howells <dhowells@redhat.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Thanks to hch's endian work, INT_GET etc are no longer used, and may as
well be removed. INT_SET is still used in the acl code, though.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31756a
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Move it from the attr code to the transaction code and make
the attr code call the new function.

We rolltrans is really usefull whenever we want to use rolling
transaction, should be generic, it isn't dependent on any part
of the attr code anyway.

We use this excuse to change all the:

if ((error = xfs_attr_rolltrans()))

calls into:

error = xfs_trans_roll();

if (error)

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31729a
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Add a helper to free the m_fsname/m_rtname/m_logname allocations and use
it properly for all mount failure cases. Also switch the allocations for
these to kstrdup while we're at it.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31728a
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

We will need that to be able to calculate the size of log we need for a
specific attr (for Create+EA). The local flag is needed so that we can
fail if we run into ENOSPC when trying to alloc blocks.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31727a
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Tim Shimmin <tes@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

If we allow incore extent tree allocations to recurse into the
filesystem under memory pressure, new delayed allocations through
xfs_iomap_write_delay() can deadlock on themselves if memory
reclaim tries to write back dirty pages from that inode.

It will deadlock in xfs_iomap_write_allocate() trying to take the
ilock we already hold. This can also show up as complex ABBA deadlocks
when multiple threads are triggering memory reclaim when trying to
allocate extents.

The main cause of this is the fact that delayed allocation is not done in
a transaction, so KM_NOFS is not automatically added to the allocations to
prevent this recursion.

Mark all allocations done for the incore inode extent tree as KM_NOFS to
ensure they never recurse back into the filesystem.

Version 2: o KM_NOFS implies KM_SLEEP, so just use KM_NOFS

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31726a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

xfs_vtoi() is redundant and only unsed in small sections of code.
Replace them with widely used XFS_I() inline and kill xfs_vtoi().

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31725a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Replace XFS_ITOV() with the new VFS_I() inline.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31724a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

Replace XFS_ITOV_NULL() with the new VFS_I() inline.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31722a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

In several places we directly convert from the XFS inode
to the linux (VFS) inode by a simple deference of ip->i_vnode.
We should not do this - a helper function should be used to
extract the VFS inode from the XFS inode.

Introduce the function VFS_I() to extract the VFS inode
from the XFS inode. The name was chosen to match XFS_I() which
is used to extract the XFS inode from the VFS inode.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31720a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Niv Sardi <xaiki@sgi.com>
Signed-off-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

We should not access a buffer after dropping it's reference count
otherwise we could race with another thread that releases the final
reference count and frees the buffer causing us to access potentially
unmapped memory. The bug this change fixes only occured on DEBUG XFS since
the offending code was in an ASSERT.

SGI-PV: 984429

SGI-Modid: xfs-linux-melb:xfs-kern:31715a
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>
Signed-off-by: David Chinner <david@fromorbit.com>

This keeps xfs_lowbit64 as it was since there aren't good generic helpers
there ... Patch inspired by Andi Kleen.

SGI-PV: 981498

SGI-Modid: xfs-linux-melb:xfs-kern:31472a
Signed-off-by: David Chinner <david@fromorbit.com>
Signed-off-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Donald Douwsma <donaldd@sgi.com>
Signed-off-by: Lachlan McIlroy <lachlan@sgi.com>

* 'for-linus' of git://git.o-hand.com/linux-mfd:
  mfd: tc6393 cleanup and update
  mfd: have TMIO drivers and subdevices depend on ARM
  mfd: TMIO MMC driver
  mfd: driver for the TMIO NAND controller
  mfd: t7l66 MMC platform data
  mfd: tc6387 MMC platform data
  mfd: Fix 7l66 and 6387 according to the new mfd-core API
  mfd: Fix tc6393 according to the new tmio.h
  mfd: driver for the TC6387XB TMIO controller.
  mfd: driver for the T7L66XB TMIO SoC
  mfd: TMIO MMC structures and accessors.

* 'i2c-for-linus' of git://jdelvare.pck.nerim.net/jdelvare-2.6:
  hwmon: (lm75) Drop legacy i2c driver
  i2c: correct some size_t printk formats
  i2c: Check for address business before creating clients
  i2c: Let users select algorithm drivers manually again
  i2c: Fix NULL pointer dereference in i2c_new_probed_device
  i2c: Fix oops on bus multiplexer driver loading

* git://git.kernel.org/pub/scm/linux/kernel/git/wim/linux-2.6-watchdog:
  [WATCHDOG] pcwd.c - fix open_allowed type.
  [WATCHDOG] fix watchdog/ixp4xx_wdt.c compilation
  [WATCHDOG] fix watchdog/wdt285.c compilation
  [WATCHDOG] fix watchdog/at91rm9200_wdt.c compilation
  [WATCHDOG] fix watchdog/shwdt.c compilation
  [WATCHDOG] fix watchdog/txx9wdt.c compilation
  [WATCHDOG] MAINTAINERS: remove ZF MACHZ WATCHDOG entry
  [WATCHDOG] Fix build with CONFIG_ITCO_VENDOR_SUPPORT=n

* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc:
  powerpc: Remove include/linux/harrier_defs.h
  powerpc: Do not ignore arch/powerpc/include
  powerpc: Delete completed "ppc removal" task from feature removal file
  powerpc/mm: Fix attribute confusion with htab_bolt_mapping()
  powerpc/pci: Don't keep ISA memory hole resources in the tree
  powerpc: Zero fill the return values of rtas argument buffer
  powerpc/4xx: Update defconfig files for 2.6.27-rc1
  powerpc/44x: Incorrect NOR offset in Warp DTS
  powerpc/44x: Warp DTS changes for board updates
  powerpc/4xx: Cleanup Warp for i2c driver changes.
  powerpc/44x: Adjust warp-nand resource end address

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jbarnes/pci-2.6:
  PCI: Limit VPD length for Broadcom 5708S
  PCI PM: Export pci_pme_active to drivers
  PCI: remove duplicate symbol from pci_ids.h
  PCI: check the return value of device_create_bin_file() in pci_create_bus()
  PCI: fully restore MSI state at resume time
  DMA: make dma-coherent.c documentation kdoc-friendly
  PCI: make pci_register_driver() a macro
  PCI: add Broadcom 5708S to VPD length quirk

While testing our KVM code for s390 (starting and killall kvm in a loop)
I can reproduce the following oops:

  Unable to handle kernel pointer dereference at virtual kernel address 6b6b6b6b6b6b6000 Oops: 0038 [#1] SMP
  Modules linked in: dm_multipath sunrpc qeth_l3 qeth_l2 dm_mod qeth
  ccwgroup CPU: 1 Not tainted 2.6.27-rc1 #54
  Process kuli (pid: 4409, task: 00000000b6aa5940, ksp: 00000000b7343e10)
  Krnl PSW : 0704e00180000000 00000000002e0b8c
  (disassociate_ctty+0x1c0/0x288) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3
  CC:2 PM:0 EA:3 Krnl GPRS: 0000000000000000 6b6b6b6b6b6b6b6b
  0000000000000001 00000000000003a6 00000000002e0a46 00000000004b4160
  0000000000000001 00000000bbd79758 00000000b7343e58 00000000b8854148
  00000000bd34dea0 00000000b7343c20 0000000000000001 00000000004b6d08
  00000000002e0a46 00000000b7343c20 Krnl Code: 00000000002e0b7e:
  eb9fb0a00004	lmg	%r9,%r15,160(%r11) 00000000002e0b84:
  07f4		bcr	15,%r4 00000000002e0b86:
  e31090080004	lg	%r1,8(%r9) >00000000002e0b8c:
  d501109cd000	clc	156(2,%r1),0(%r13) 00000000002e0b92:
  a784ff5d		brc	8,2e0a4c 00000000002e0b96:
  b9040029		lgr	%r2,%r9 00000000002e0b9a:
  c0e5fffff9c3	brasl	%r14,2dff20 00000000002e0ba0:
  a7f4ff56		brc	15,2e0a4c Call Trace:
  ([<00000000002e0a46>] disassociate_ctty+0x7a/0x288)
   [<0000000000141fe6>] do_exit+0x212/0x8d4
   [<0000000000142708>] do_group_exit+0x60/0xcc
   [<0000000000150660>] get_signal_to_deliver+0x270/0x3ac
   [<000000000010bfd6>] do_signal+0x8e/0x8dc
   [<0000000000113772>] sysc_sigpending+0xe/0x22
   [<000001ff0000b134>] 0x1ff0000b134
  INFO: lockdep is turned off.
  Last Breaking-Event-Address:
   [<00000000002e0a48>] disassociate_ctty+0x7c/0x288
  Kernel panic - not syncing: Fatal exception: panic_on_oops

It seems that tty was already free in disassocate_ctty when it tries
to dereference tty->driver.

After moving the lock_kernel before the mutex_unlock, I can no longer
reproduce the problem.

[ This is a temporary partial fix for the documented and long standing
  race in disassociate_tty.  This stops most problem cases for now.

  For the next release the -next tree has an initial implementation of
  kref counting for tty structures and this quickfix will be dropped.

                                                              - Alan ]
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by; Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>