Commit Graph

73 Commits

Author SHA1 Message Date
Al Viro babfe56046 exofs: i_nlink races in rename()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-03-03 01:28:17 -05:00
Boaz Harrosh 0b0abeaf3d Revert "exofs: Set i_mapping->backing_dev_info anyway"
This reverts commit 115e19c535.

Apparently setting inode->bdi to one's own sb->s_bdi stops VFS from
sending *read-aheads*.  This problem was bisected to this commit.  A
revert fixes it.  I'll investigate farther why is this happening for the
next Kernel, but for now a revert.

I'm sending to stable@kernel.org as well, since it exists also in
2.6.37.  2.6.36 is good and does not have this patch.

CC: Stable Tree <stable@kernel.org>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-02-02 17:53:27 -08:00
Nick Piggin fa0d7e3de6 fs: icache RCU free inodes
RCU free the struct inode. This will allow:

- Subsequent store-free path walking patch. The inode must be consulted for
  permissions when walking, so an RCU inode reference is a must.
- sb_inode_list_lock to be moved inside i_lock because sb list walkers who want
  to take i_lock no longer need to take sb_inode_list_lock to walk the list in
  the first place. This will simplify and optimize locking.
- Could remove some nested trylock loops in dcache code
- Could potentially simplify things a bit in VM land. Do not need to take the
  page lock to follow page->mapping.

The downsides of this is the performance cost of using RCU. In a simple
creat/unlink microbenchmark, performance drops by about 10% due to inability to
reuse cache-hot slab objects. As iterations increase and RCU freeing starts
kicking over, this increases to about 20%.

In cases where inode lifetimes are longer (ie. many inodes may be allocated
during the average life span of a single inode), a lot of this cache reuse is
not applicable, so the regression caused by this patch is smaller.

The cache-hot regression could largely be avoided by using SLAB_DESTROY_BY_RCU,
however this adds some complexity to list walking and store-free path walking,
so I prefer to implement this at a later date, if it is shown to be a win in
real situations. I haven't found a regression in any non-micro benchmark so I
doubt it will be a problem.

Signed-off-by: Nick Piggin <npiggin@kernel.dk>
2011-01-07 17:50:26 +11:00
Al Viro 3c26ff6e49 convert get_sb_nodev() users
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-29 04:16:31 -04:00
Al Viro 7de9c6ee3e new helper: ihold()
Clones an existing reference to inode; caller must already hold one.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25 21:26:11 -04:00
Christoph Hellwig c37650161a fs: add sync_inode_metadata
Add a new helper to write out the inode using the writeback code,
that is including the correct dirty bit and list manipulation.  A few
of filesystems already opencode this, and a lot of others should be
using it instead of using write_inode_now which also writes out the
data.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-10-25 21:18:19 -04:00
Boaz Harrosh fe2fd9ed5b exofs: Remove inode->i_count manipulation in exofs_new_inode
exofs_new_inode() was incrementing the inode->i_count and
decrementing it in create_done(), in a bad attempt to make sure
the inode will still be there when the asynchronous create_done()
finally arrives. This was very stupid because iput() was not called,
and if it was actually needed, it would leak the inode.

However all this is not needed, because at exofs_evict_inode()
we already wait for create_done() by waiting for the
object_created event. Therefore remove the superfluous ref counting
and just Thicken the comment at exofs_evict_inode() a bit.

While at it change places that open coded wait_obj_created()
to call the already available wrapper.

CC: Dave Chinner <dchinner@redhat.com>
CC: Christoph Hellwig <hch@lst.de>
CC: Nick Piggin <npiggin@kernel.dk>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2010-10-25 18:03:07 +02:00
Joe Perches 571f7f46bf fs/exofs: typo fix of faild to failed
Signed-off-by: Joe Perches <joe@perches.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2010-10-25 18:02:49 +02:00
Boaz Harrosh 115e19c535 exofs: Set i_mapping->backing_dev_info anyway
Though it has been promised that inode->i_mapping->backing_dev_info
is not used and the supporting code is fine. Until the pointer
will default to NULL, I'd rather it points to the correct thing
regardless.

At least for future infrastructure coder it is a clear indication
of where are the key points that inodes are initialized.
I know because it took me time to find this out.

Signed-off-by: Boaz Harrosh <Boaz Harrosh bharrosh@panasas.com>
2010-10-18 20:16:02 +02:00
Boaz Harrosh 7aebf4106b exofs: Cleaup read path in regard with read_for_write
Last BUG fix added a flag to the the page_collect structure
to communicate with readpage_strip. This calls for a clean up
removing that flag's reincarnations in the read functions
parameters.

Signed-off-by: Boaz Harrosh <Boaz Harrosh bharrosh@panasas.com>
2010-10-18 20:16:02 +02:00
Boaz Harrosh f17b1f9f1a exofs: Fix double page_unlock BUG in write_begin/end
This BUG is there since the first submit of the code, but only triggered
in last Kernel. It's timing related do to the asynchronous object-creation
behaviour of exofs. (Which should be investigated farther)

The bug is obvious hence the fixed.

Signed-off-by: Boaz Harrosh <Boaz Harrosh bharrosh@panasas.com>
2010-10-08 11:26:54 -04:00
Linus Torvalds bf25db3654 Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osd
* 'for-linus' of git://git.open-osd.org/linux-open-osd:
  exofs: Fix groups code when num_devices is not divisible by group_width
  exofs: Remove useless optimization
  exofs: exofs_file_fsync and exofs_file_flush correctness
  exofs: Remove superfluous dependency on buffer_head and writeback
2010-08-11 09:19:43 -07:00
Linus Torvalds 2f9e825d3e Merge branch 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block
* 'for-2.6.36' of git://git.kernel.dk/linux-2.6-block: (149 commits)
  block: make sure that REQ_* types are seen even with CONFIG_BLOCK=n
  xen-blkfront: fix missing out label
  blkdev: fix blkdev_issue_zeroout return value
  block: update request stacking methods to support discards
  block: fix missing export of blk_types.h
  writeback: fix bad _bh spinlock nesting
  drbd: revert "delay probes", feature is being re-implemented differently
  drbd: Initialize all members of sync_conf to their defaults [Bugz 315]
  drbd: Disable delay probes for the upcomming release
  writeback: cleanup bdi_register
  writeback: add new tracepoints
  writeback: remove unnecessary init_timer call
  writeback: optimize periodic bdi thread wakeups
  writeback: prevent unnecessary bdi threads wakeups
  writeback: move bdi threads exiting logic to the forker thread
  writeback: restructure bdi forker loop a little
  writeback: move last_active to bdi
  writeback: do not remove bdi from bdi_list
  writeback: simplify bdi code a little
  writeback: do not lose wake-ups in bdi threads
  ...

Fixed up pretty trivial conflicts in drivers/block/virtio_blk.c and
drivers/scsi/scsi_error.c as per Jens.
2010-08-10 15:22:42 -07:00
Al Viro 4ec70c9b46 convert exofs to ->evict_inode()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:48:24 -04:00
Boaz Harrosh 2f246fd0f1 exofs: New truncate sequence
These changes are crafted based on the similar
conversion done to ext2 by Nick Piggin.

* Remove the deprecated ->truncate vector. Let exofs_setattr
  take care of on-disk size updates.
* Call truncate_pagecache on the unused pages if
  write_begin/end fails.
* Cleanup exofs_delete_inode that did stupid inode
  writes and updates on an inode that will be
  removed.
* And finally get rid of exofs_get_block. We never
  had any blocks it was all for calling nobh_truncate_page.
  nobh_truncate_page is not actually needed in exofs since
  the last page is complete and gone, just like all the other
  pages. There is no partial blocks in exofs.

I've tested with this patch, and there are no apparent
failures, so far.

CC: Nick Piggin <npiggin@suse.de>
CC: Christoph Hellwig <hch@lst.de>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:47:41 -04:00
Christoph Hellwig 1025774ce4 remove inode_setattr
Replace inode_setattr with opencoded variants of it in all callers.  This
moves the remaining call to vmtruncate into the filesystem methods where it
can be replaced with the proper truncate sequence.

In a few cases it was obvious that we would never end up calling vmtruncate
so it was left out in the opencoded variant:

 spufs: explicitly checks for ATTR_SIZE earlier
 btrfs,hugetlbfs,logfs,dlmfs: explicitly clears ATTR_SIZE earlier
 ufs: contains an opencoded simple_seattr + truncate that sets the filesize just above

In addition to that ncpfs called inode_setattr with handcrafted iattrs,
which allowed to trim down the opencoded variant.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-08-09 16:47:37 -04:00
Christoph Hellwig 7b6d91daee block: unify flags for struct bio and struct request
Remove the current bio flags and reuse the request flags for the bio, too.
This allows to more easily trace the type of I/O from the filesystem
down to the block driver.  There were two flags in the bio that were
missing in the requests:  BIO_RW_UNPLUG and BIO_RW_AHEAD.  Also I've
renamed two request flags that had a superflous RW in them.

Note that the flags are in bio.h despite having the REQ_ name - as
blkdev.h includes bio.h that is the only way to go for now.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <jaxboe@fusionio.com>
2010-08-07 18:20:39 +02:00
Boaz Harrosh 5002dd18c5 exofs: Fix groups code when num_devices is not divisible by group_width
There is a bug when num_devices is not divisible by group_width * mirrors.
We would not return to the proper device and offset when looping on to the
next group.

The fix makes code simpler actually.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2010-08-04 13:17:58 +03:00
Boaz Harrosh 6e31609b1d exofs: Remove useless optimization
We used to compact all used devices in an IO to the beginning
of the device array in an io_state. And keep a last device used
so in later loops we don't iterate on all device slots. This
does not prevent us from checking if slots are empty since in
reads we only read from a single mirror and jump to the next
mirror-set.

This optimization is marginal, and needlessly complicates the
code. Specially when we will later want to support raid/456
with same abstract code. So remove the distinction between
"dev" and "comp". Only "dev" is used both as the device used
and as the index (component) in the device array.

[Note that now the io_state->dev member is redundant but I
 keep it because I might want to optimize by only IOing a
 single group, though keeping a group_width*mirrors devices
 in io_state, we now keep num-devices in each io_state]

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2010-08-04 13:17:57 +03:00
Boaz Harrosh b284834929 exofs: exofs_file_fsync and exofs_file_flush correctness
As per Christoph advise: no need to call filemap_write_and_wait().
In exofs all metadata is at the inode so just writing the inode is
all is needed. ->fsync implies this must be done synchronously.

But now exofs_file_fsync can not be used by exofs_file_flush.
vfs_fsync() should do that job correctly.

FIXME: remove the sb_sync and fix that sb_update better.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2010-08-04 13:17:56 +03:00
Boaz Harrosh 85dc7878c6 exofs: Remove superfluous dependency on buffer_head and writeback
exofs_releasepage && exofs_invalidatepage are never called.
Leave the WARN_ONs but remove any code. Remove the

cleanup other stale #includes.

Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2010-08-04 13:17:55 +03:00
Christoph Hellwig 7ea8085910 drop unused dentry argument to ->fsync
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-27 22:05:02 -04:00
Linus Torvalds 0163916f1d Merge branch 'for-linus' of git://git.open-osd.org/linux-open-osd
* 'for-linus' of git://git.open-osd.org/linux-open-osd:
  exofs: confusion between kmap() and kmap_atomic() api
  exofs: Add default address_space_operations
2010-05-24 07:57:41 -07:00
Dmitry Monakhov e00117f14f exofs: replace inode uid,gid,mode initialization with helper function
Ack-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Dmitry Monakhov <dmonakhov@openvz.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2010-05-21 18:31:23 -04:00
Dan Carpenter ddf08f4b90 exofs: confusion between kmap() and kmap_atomic() api
For kmap_atomic() we call kunmap_atomic() on the returned pointer.
That's different from kmap() and kunmap() and so it's easy to get them
backwards.

Cc: Stable <stable@kernel.org>
Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
2010-05-17 13:50:58 +03:00