Calling into memory reclaim with a locked inode buffer can deadlock
if memory reclaim tries to lock the inode buffer during inode
teardown. Convert the relevant memory allocations to use KM_NOFS to
avoid this deadlock condition.
Reported-by: NPeter Watkins <treestem@gmail.com>
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NAlex Elder <aelder@sgi.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

xfs_trans_add_item() is called with ip->i_ilock held, which means it
is unsafe for memory reclaim to recurse back into the filesystem
(ilock is required in writeback). Hence the allocation needs to be
KM_NOFS to avoid recursion.

Lockdep report indicating memory allocation being called with the
ip->i_ilock held is as follows:

[ 1749.866796] =================================
[ 1749.867788] [ INFO: inconsistent lock state ]
[ 1749.868327] 2.6.35-rc3-dgc+ #25
[ 1749.868741] ---------------------------------
[ 1749.868741] inconsistent {IN-RECLAIM_FS-W} -> {RECLAIM_FS-ON-W} usage.
[ 1749.868741] dd/2835 [HC0[0]:SC0[0]:HE1:SE1] takes:
[ 1749.868741]  (&(&ip->i_lock)->mr_lock){++++?.}, at: [<ffffffff813170fb>] xfs_ilock+0x10b/0x190
[ 1749.868741] {IN-RECLAIM_FS-W} state was registered at:
[ 1749.868741]   [<ffffffff810b3a97>] __lock_acquire+0x437/0x1450
[ 1749.868741]   [<ffffffff810b4b56>] lock_acquire+0xa6/0x160
[ 1749.868741]   [<ffffffff810a20b5>] down_write_nested+0x65/0xb0
[ 1749.868741]   [<ffffffff813170fb>] xfs_ilock+0x10b/0x190
[ 1749.868741]   [<ffffffff8134e819>] xfs_reclaim_inode+0x99/0x310
[ 1749.868741]   [<ffffffff8134f56b>] xfs_inode_ag_walk+0x8b/0x150
[ 1749.868741]   [<ffffffff8134f6bb>] xfs_inode_ag_iterator+0x8b/0xf0
[ 1749.868741]   [<ffffffff8134f7a8>] xfs_reclaim_inode_shrink+0x88/0x90
[ 1749.868741]   [<ffffffff81119d07>] shrink_slab+0x137/0x1a0
[ 1749.868741]   [<ffffffff8111bbe1>] balance_pgdat+0x421/0x6a0
[ 1749.868741]   [<ffffffff8111bf7d>] kswapd+0x11d/0x320
[ 1749.868741]   [<ffffffff8109ce56>] kthread+0x96/0xa0
[ 1749.868741]   [<ffffffff81035de4>] kernel_thread_helper+0x4/0x10
[ 1749.868741] irq event stamp: 4234335
[ 1749.868741] hardirqs last  enabled at (4234335): [<ffffffff81147d25>] kmem_cache_free+0x115/0x220
[ 1749.868741] hardirqs last disabled at (4234334): [<ffffffff81147c4d>] kmem_cache_free+0x3d/0x220
[ 1749.868741] softirqs last  enabled at (4233112): [<ffffffff81084dd2>] __do_softirq+0x142/0x260
[ 1749.868741] softirqs last disabled at (4233095): [<ffffffff81035edc>] call_softirq+0x1c/0x50
[ 1749.868741] 
[ 1749.868741] other info that might help us debug this:
[ 1749.868741] 2 locks held by dd/2835:
[ 1749.868741]  #0:  (&(&ip->i_iolock)->mr_lock#2){+.+.+.}, at: [<ffffffff81316edd>] xfs_ilock_nowait+0xed/0x200
[ 1749.868741]  #1:  (&(&ip->i_lock)->mr_lock){++++?.}, at: [<ffffffff813170fb>] xfs_ilock+0x10b/0x190
[ 1749.868741] 
[ 1749.868741] stack backtrace:
[ 1749.868741] Pid: 2835, comm: dd Not tainted 2.6.35-rc3-dgc+ #25
[ 1749.868741] Call Trace:
[ 1749.868741]  [<ffffffff810b1faa>] print_usage_bug+0x18a/0x190
[ 1749.868741]  [<ffffffff8104264f>] ? save_stack_trace+0x2f/0x50
[ 1749.868741]  [<ffffffff810b2400>] ? check_usage_backwards+0x0/0xf0
[ 1749.868741]  [<ffffffff810b2f11>] mark_lock+0x331/0x400
[ 1749.868741]  [<ffffffff810b3047>] mark_held_locks+0x67/0x90
[ 1749.868741]  [<ffffffff810b3111>] lockdep_trace_alloc+0xa1/0xe0
[ 1749.868741]  [<ffffffff81147419>] kmem_cache_alloc+0x39/0x1e0
[ 1749.868741]  [<ffffffff8133f954>] kmem_zone_alloc+0x94/0xe0
[ 1749.868741]  [<ffffffff8133f9be>] kmem_zone_zalloc+0x1e/0x50
[ 1749.868741]  [<ffffffff81335f02>] xfs_trans_add_item+0x72/0xb0
[ 1749.868741]  [<ffffffff81339e41>] xfs_trans_ijoin+0xa1/0xd0
[ 1749.868741]  [<ffffffff81319f82>] xfs_itruncate_finish+0x312/0x5d0
[ 1749.868741]  [<ffffffff8133cb87>] xfs_free_eofblocks+0x227/0x280
[ 1749.868741]  [<ffffffff8133cd18>] xfs_release+0x138/0x190
[ 1749.868741]  [<ffffffff813464c5>] xfs_file_release+0x15/0x20
[ 1749.868741]  [<ffffffff81150ebf>] fput+0x13f/0x260
[ 1749.868741]  [<ffffffff8114d8c2>] filp_close+0x52/0x80
[ 1749.868741]  [<ffffffff8114d9a9>] sys_close+0xb9/0x120
[ 1749.868741]  [<ffffffff81034ff2>] system_call_fastpath+0x16/0x1b
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NAlex Elder <aelder@sgi.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

xfs_ireclaim has to get and put te pag structure because it is only
called with the inode to reclaim. The one caller of this function
already has a reference on the pag and a pointer to is, so move the
radix tree delete to the caller and remove xfs_ireclaim completely.
This avoids a xfs_perag_get/put on every inode being reclaimed.

The overhead was noticed in a bug report at:

https://bugzilla.kernel.org/show_bug.cgi?id=16348Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NAlex Elder <aelder@sgi.com>
Signed-off-by: NDave Chinner <david@fromorbit.com>

xfs_buf_read() fails to detect dispatch errors before attempting to
wait on sychronous IO. If there was an error, it will get stuck
forever, waiting for an I/O that was never started. Make sure the
error is detected correctly.

Further, such a failure can leave locked pages in the page cache
which will cause a later operation to hang on the page. Ensure that
we correctly process pages in the buffers when we get a dispatch
error.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NDave Chinner <david@fromorbit.com>

I missed Dave Chinner's second revision of this change, and pushed
his first version out to the repository instead.

	commit a476c59ebb279d738718edc0e3fb76aab3687114
	Author: Dave Chinner <dchinner@redhat.com>

This commit compensates for that by moving a block of code up a bit
further, with a result that matches the the effect of Dave's second
version.

Dave's first version was:
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Dave's second version was:
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAlex Elder <aelder@sgi.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>

The open_exec file operation is only added by the external dmapi
patch.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NAlex Elder <aelder@sgi.com>
Signed-off-by: NAlex Elder <aelder@sgi.com>

These days we always have buffers thanks to ->page_mkwrite.  And we
already have an assert a few lines above tripping in case that was
not true due to a bug.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAlex Elder <aelder@sgi.com>

We only need disable I/O from direct or memcg reclaim.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAlex Elder <aelder@sgi.com>

We do need a barrier for the first buffer of a split log write.
Otherwise we might incorrectly stamp the tail LSN into transactions
in the first part of the split write, or not flush data I/O before
updating the inode size.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Signed-off-by: NAlex Elder <aelder@sgi.com>

Currently we don't remove the XFS mount from the shrinker list until
late in the unmount path. By this time, we have already torn down
the internals of the filesystem (e.g. the per-ag structures), and
hence if the shrinker is executed between the teardown and the
unregistering, the shrinker will get NULL per-ag structure pointers
and panic trying to dereference them.

Fix this by removing the xfs mount from the shrinker list before
tearing down it's internal structures.
Signed-off-by: NDave Chinner <dchinner@redhat.com>
Reviewed-by: NEric Sandeen <sandeen@redhat.com>
Signed-off-by: NAlex Elder <aelder@sgi.com>

Replace the xfs_itrace_entry catchall with specific trace points.  For
most simple callers we now use the simple inode class, which used to
be the iget class, but add more details tracing for namespace events,
which now includes the name of the directory entries manipulated.

Remove the xfs_inactive trace point, which is a duplicate of the clear_inode
one, and the xfs_change_file_space trace point, which is immediately
followed by the more specific alloc/free space trace points.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

xfs_iput is just a small wrapper for xfs_iunlock + IRELE.  Having this
out of line wrapper means the trace events in those two can't track
their caller properly.  So just remove the wrapper and opencode the
unlock + rele in the few callers.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

We never get an i_mode of 0 or a locked VFS inode until we pass in the
XFS_IGET_CREATE flag to xfs_iget, which makes xfs_iput_new equivalent to
xfs_iput for the only caller.  In addition to that xfs_nfs_get_inode
does not even need to lock the inode given that the generation never changes
for a life inode, so just pass a 0 lock_flags to xfs_iget and release
the inode using IRELE in the error path.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

The xfs_iget_alloc/found tracepoints are a bit misnamed and misplaced.
Rename them to xfs_iget_hit/xfs_iget_miss and move them to the beggining
of the xfs_iget_cache_hit/miss functions.  Add a new xfs_iget_reclaim_fail
tracepoint for the case where we fail to re-initialize a VFS inode,
and add a second instance of the xfs_iget_skip tracepoint for the case
of a failed igrab() call.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

The tracing code can't print flags defined as enums.  Most flags that
we want to print are defines as macros already, but move the few remaining
ones over to make the trace output more useful.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

On the final put of a superblock the VFS already calls sync_filesystem
for us to write out all data and wait for it.  No need to start another
asynchronous writeback inside ->put_super.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Remove the flags argument to  __xfs_get_blocks as we can easily derive
it from the direct argument, and remove the unused BMAPI_MMAP flag.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

xfs_iomap passes a xfs_bmbt_irec pointer to xfs_iomap_write_direct and
xfs_iomap_write_allocate to give them the results of our read-only
xfs_bmapi query.  Instead of allocating a new xfs_bmbt_irec on stack
for the next call to xfs_bmapi re use the one we got passed as it's not
used after this point.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

We already rely on the fact that the sync code will cause a synchronous
log force later on (currently via xfs_fs_sync_fs -> xfs_quiesce_data ->
xfs_sync_data), so no need to do this here.  This allows us to avoid
a lot of synchronous log forces during sync, which pays of especially
with delayed logging enabled.   Some compilebench numbers that show
this:

xfs (delayed logging, 256k logbufs)
===================================

intial create		  25.94 MB/s	  25.75 MB/s	  25.64 MB/s
create			   8.54 MB/s	   9.12 MB/s	   9.15 MB/s
patch			   2.47 MB/s	   2.47 MB/s	   3.17 MB/s
compile			  29.65 MB/s	  30.51 MB/s	  27.33 MB/s
clean			  90.92 MB/s	  98.83 MB/s	 128.87 MB/s
read tree		  11.90 MB/s	  11.84 MB/s	   8.56 MB/s
read compiled		  28.75 MB/s	  29.96 MB/s	  24.25 MB/s
delete tree		8.39 seconds	8.12 seconds	8.46 seconds
delete compiled		8.35 seconds	8.44 seconds	5.11 seconds
stat tree		6.03 seconds	5.59 seconds	5.19 seconds
stat compiled tree	9.00 seconds	9.52 seconds	8.49 seconds

xfs + write_inode log_force removal
===================================
intial create		  25.87 MB/s	  25.76 MB/s	  25.87 MB/s
create			  15.18 MB/s	  14.80 MB/s	  14.94 MB/s
patch			   3.13 MB/s	   3.14 MB/s	   3.11 MB/s
compile			  36.74 MB/s	  37.17 MB/s	  36.84 MB/s
clean			 226.02 MB/s	 222.58 MB/s	 217.94 MB/s
read tree		  15.14 MB/s	  15.02 MB/s	  15.14 MB/s
read compiled tree	  29.30 MB/s	  29.31 MB/s	  29.32 MB/s
delete tree		6.22 seconds	6.14 seconds	6.15 seconds
delete compiled tree	5.75 seconds	5.92 seconds	5.81 seconds
stat tree		4.60 seconds	4.51 seconds	4.56 seconds
stat compiled tree	4.07 seconds	3.87 seconds	3.96 seconds

In addition to that also remove the delwri inode flush that is unessecary
now that bulkstat is always coherent.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

The writepage implementation in XFS still tries to deal with dirty but
unmapped buffers which used to caused by writes through shared mmaps.  Since
the introduction of ->page_mkwrite these can't happen anymore, so remove the
code dealing with them.

Note that the all_bh variable which causes us to start I/O on all buffers on
the pages was controlled by the count of unmapped buffers, which also
included those not actually dirty.  It's now unconditionally initialized to
0 but set to 1 for the case of small file size extensions.  It probably can
be removed entirely, but that's left for another patch.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Currently the xfs releasepage implementation has code to deal with converting
delayed allocated and unwritten space.  But we never get called for those as
we always convert delayed and unwritten space when cleaning a page, or drop
the state from the buffers in block_invalidatepage.  We still keep a WARN_ON
on those cases for now, but remove all the case dealing with it, which allows
to fold xfs_page_state_convert into xfs_vm_writepage and remove the !startio
case from the whole writeback path.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

xfstests 194 first truncats a file back and then extends it again by
truncating it to a larger size.  This causes discard_buffer to drop
the mapped, but not the uptodate bit and thus creates something that
xfs_page_state_convert takes for unmapped space created by mmap because
it doesn't check for the dirty bit, which also gets cleared by
discard_buffer and checked by other ->writepage implementations like
block_write_full_page.  Handle this kind of buffers early, and unlike
Eric's first version of the patch simply ASSERT that the buffers is
dirty, given that the mmap write case can't happen anymore since the
introduction of ->page_mkwrite.  The now dead code dealing with that
will be deleted in a follow on patch.
Signed-off-by: NEric Sandeen <sandeen@sandeen.net>
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

This code was introduced four years ago in commit
3e57ecf6 without any review and has
been unused since.  Remove it just as the rest of the code introduced
in that commit to reduce that stack usage and complexity in this central
piece of code.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

By making this member a void pointer we can get rid of a lot of pointless
casts.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Currently we need to either call IHOLD or xfs_trans_ihold on an inode when
joining it to a transaction via xfs_trans_ijoin.

This patches instead makes xfs_trans_ijoin usable on it's own by doing
an implicity xfs_trans_ihold, which also allows us to drop the third
argument.  For the case where we want to hold a reference on the inode
a xfs_trans_ijoin_ref wrapper is added which does the IHOLD and marks
the inode for needing an xfs_iput.  In addition to the cleaner interface
to the caller this also simplifies the implementation.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Get rid of the xfs_buf_pin/xfs_buf_unpin/xfs_buf_ispin helpers and opencode
them in their only callers, just like we did for the inode pinning a while
ago.  Also remove duplicate trace points - the bufitem tracepoints cover
all the information that is present in a buffer tracepoint.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Stop the function pointer casting madness and give all the li_cb instances
correct prototype.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Stop the function pointer casting madness and give all the xfs_item_ops the
correct prototypes.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

The unpin_remove item operation instances always share most of the
implementation with the respective unpin implementation.  So instead
of keeping two different entry points add a remove flag to the unpin
operation and share the code more easily.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Currently we track log item descriptor belonging to a transaction using a
complex opencoded chunk allocator.  This code has been there since day one
and seems to work around the lack of an efficient slab allocator.

This patch replaces it with dynamically allocated log item descriptors
from a dedicated slab pool, linked to the transaction by a linked list.

This allows to greatly simplify the log item descriptor tracking to the
point where it's just a couple hundred lines in xfs_trans.c instead of
a separate file.  The external API has also been simplified while we're
at it - the xfs_trans_add_item and xfs_trans_del_item functions to add/
delete items from a transaction have been simplified to the bare minium,
and the xfs_trans_find_item function is replaced with a direct dereference
of the li_desc field.  All debug code walking the list of log items in
a transaction is down to a simple list_for_each_entry.

Note that we could easily use a singly linked list here instead of the
double linked list from list.h as the fastpath only does deletion from
sequential traversal.  But given that we don't have one available as
a library function yet I use the list.h functions for simplicity.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <david@fromorbit.com>

Dmapi support was never merged upstream, but we still have a lot of hooks
bloating XFS for it, all over the fast pathes of the filesystem.

This patch drops over 700 lines of dmapi overhead.  If we'll ever get HSM
support in mainline at least the namespace events can be done much saner
in the VFS instead of the individual filesystem, so it's not like this
is much help for future work.
Signed-off-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NDave Chinner <dchinner@redhat.com>

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
  Input: synaptics - relax capability ID checks on newer hardware
  Input: twl40300-keypad - fix handling of "all ground" rows
  Input: gamecon - reference correct pad in gc_psx_command()
  Input: gamecon - reference correct input device in NES mode
  Input: w90p910_keypad - change platfrom driver name to 'nuc900-kpi'
  Input: i8042 - add Gigabyte Spring Peak to dmi_noloop_table
  Input: qt2160 - rename kconfig symbol name

* 'drm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/drm-2.6:
  drm/radeon/kms: add quirk to make HP DV5000 laptop resume
  drm/radeon/kms: fix RADEON_INFO_CRTC_FROM_ID info ioctl
  Fix ttm_page_alloc.c build breakage
  drm/radeon/kms: fix legacy LVDS dpms sequence
  drm/radeon/kms: drop taking lock around crtc lookup.

* git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6:
  crypto: talitos - fix bug in sg_copy_end_to_buffer