Commit Graph

699 Commits

Author SHA1 Message Date
Pavel Emelyanov 8373200b12 fuse: Trust kernel i_size only
Make fuse think that when writeback is on the inode's i_size is always
up-to-date and not update it with the value received from the userspace.
This is done because the page cache code may update i_size without letting
the FS know.

This assumption implies fixing the previously introduced short-read helper --
when a short read occurs the 'hole' is filled with zeroes.

fuse_file_fallocate() is also fixed because now we should keep i_size up to
date, so it must be updated if FUSE_FALLOCATE request succeeded.

Signed-off-by: Maxim V. Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-02 15:38:48 +02:00
Pavel Emelyanov d5cd66c58e fuse: Connection bit for enabling writeback
Off (0) by default. Will be used in the next patches and will be turned
on at the very end.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-02 15:38:48 +02:00
Pavel Emelyanov a92adc824e fuse: Prepare to handle short reads
A helper which gets called when read reports less bytes than was requested.
See patch "trust kernel i_size only" for details.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-02 15:38:47 +02:00
Pavel Emelyanov 650b22b941 fuse: Linking file to inode helper
When writeback is ON every writeable file should be in per-inode write list,
not only mmap-ed ones. Thus introduce a helper for this linkage.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-04-02 15:38:47 +02:00
Al Viro 5cb6c6c7eb generic_file_direct_write(): get rid of ppos argument
always equal to &iocb->ki_pos.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:35 -04:00
Al Viro 9e8c2af96e callers of iov_copy_from_user_atomic() don't need pagecache_disable()
... it does that itself (via kmap_atomic())

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:20 -04:00
Al Viro fbb32750a6 pipe: kill ->map() and ->unmap()
all pipe_buffer_operations have the same instances of those...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:19 -04:00
Al Viro 58bda1da4b fuse/dev: use atomic maps
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-01 23:19:18 -04:00
Rusty Russell 58f86cc89c VERIFY_OCTAL_PERMISSIONS: stricter checking for sysfs perms.
Summary of http://lkml.org/lkml/2014/3/14/363 :

  Ted: module_param(queue_depth, int, 444)
  Joe: 0444!
  Rusty: User perms >= group perms >= other perms?
  Joe: CLASS_ATTR, DEVICE_ATTR, SENSOR_ATTR and SENSOR_ATTR_2?

Side effect of stricter permissions means removing the unnecessary
S_IFREG from several callers.

Note that the BUILD_BUG_ON_ZERO((perm) & 2) test was removed: a fair
number of drivers fail this test, so that will be the debate for a
future patch.

Suggested-by: Joe Perches <joe@perches.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com> for drivers/pci/slot.c
Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2014-03-24 12:21:00 +10:30
Theodore Ts'o 02b9984d64 fs: push sync_filesystem() down to the file system's remount_fs()
Previously, the no-op "mount -o mount /dev/xxx" operation when the
file system is already mounted read-write causes an implied,
unconditional syncfs().  This seems pretty stupid, and it's certainly
documented or guaraunteed to do this, nor is it particularly useful,
except in the case where the file system was mounted rw and is getting
remounted read-only.

However, it's possible that there might be some file systems that are
actually depending on this behavior.  In most file systems, it's
probably fine to only call sync_filesystem() when transitioning from
read-write to read-only, and there are some file systems where this is
not needed at all (for example, for a pseudo-filesystem or something
like romfs).

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Cc: linux-fsdevel@vger.kernel.org
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Artem Bityutskiy <dedekind1@gmail.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Evgeniy Dushistov <dushistov@mail.ru>
Cc: Jan Kara <jack@suse.cz>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Cc: Anders Larsen <al@alarsen.net>
Cc: Phillip Lougher <phillip@squashfs.org.uk>
Cc: Kees Cook <keescook@chromium.org>
Cc: Mikulas Patocka <mikulas@artax.karlin.mff.cuni.cz>
Cc: Petr Vandrovec <petr@vandrovec.name>
Cc: xfs@oss.sgi.com
Cc: linux-btrfs@vger.kernel.org
Cc: linux-cifs@vger.kernel.org
Cc: samba-technical@lists.samba.org
Cc: codalist@coda.cs.cmu.edu
Cc: linux-ext4@vger.kernel.org
Cc: linux-f2fs-devel@lists.sourceforge.net
Cc: fuse-devel@lists.sourceforge.net
Cc: cluster-devel@redhat.com
Cc: linux-mtd@lists.infradead.org
Cc: jfs-discussion@lists.sourceforge.net
Cc: linux-nfs@vger.kernel.org
Cc: linux-nilfs@vger.kernel.org
Cc: linux-ntfs-dev@lists.sourceforge.net
Cc: ocfs2-devel@oss.oracle.com
Cc: reiserfs-devel@vger.kernel.org
2014-03-13 10:14:33 -04:00
Linus Torvalds bf3d846b78 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "Assorted stuff; the biggest pile here is Christoph's ACL series.  Plus
  assorted cleanups and fixes all over the place...

  There will be another pile later this week"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (43 commits)
  __dentry_path() fixes
  vfs: Remove second variable named error in __dentry_path
  vfs: Is mounted should be testing mnt_ns for NULL or error.
  Fix race when checking i_size on direct i/o read
  hfsplus: remove can_set_xattr
  nfsd: use get_acl and ->set_acl
  fs: remove generic_acl
  nfs: use generic posix ACL infrastructure for v3 Posix ACLs
  gfs2: use generic posix ACL infrastructure
  jfs: use generic posix ACL infrastructure
  xfs: use generic posix ACL infrastructure
  reiserfs: use generic posix ACL infrastructure
  ocfs2: use generic posix ACL infrastructure
  jffs2: use generic posix ACL infrastructure
  hfsplus: use generic posix ACL infrastructure
  f2fs: use generic posix ACL infrastructure
  ext2/3/4: use generic posix ACL infrastructure
  btrfs: use generic posix ACL infrastructure
  fs: make posix_acl_create more useful
  fs: make posix_acl_chmod more useful
  ...
2014-01-28 08:38:04 -08:00
Steven Whitehouse 9fe55eea7e Fix race when checking i_size on direct i/o read
So far I've had one ACK for this, and no other comments. So I think it
is probably time to send this via some suitable tree. I'm guessing that
the vfs tree would be the most appropriate route, but not sure that
there is one at the moment (don't see anything recent at kernel.org)
so in that case I think -mm is the "back up plan". Al, please let me
know if you will take this?

Steve.

---------------------

Following on from the "Re: [PATCH v3] vfs: fix a bug when we do some dio
reads with append dio writes" thread on linux-fsdevel, this patch is my
current version of the fix proposed as option (b) in that thread.

Removing the i_size test from the direct i/o read path at vfs level
means that filesystems now have to deal with requests which are beyond
i_size themselves. These I've divided into three sets:

 a) Those with "no op" ->direct_IO (9p, cifs, ceph)
These are obviously not going to be an issue

 b) Those with "home brew" ->direct_IO (nfs, fuse)
I've been told that NFS should not have any problem with the larger
i_size, however I've added an extra test to FUSE to duplicate the
original behaviour just to be on the safe side.

 c) Those using __blockdev_direct_IO()
These call through to ->get_block() which should deal with the EOF
condition correctly. I've verified that with GFS2 and I believe that
Zheng has verified it for ext4. I've also run the test on XFS and it
passes both before and after this change.

The part of the patch in filemap.c looks a lot larger than it really is
- there are only two lines of real change. The rest is just indentation
of the contained code.

There remains a test of i_size though, which was added for btrfs. It
doesn't cause the other filesystems a problem as the test is performed
after ->direct_IO has been called. It is possible that there is a race
that does matter to btrfs, however this patch doesn't change that, so
its still an overall improvement.

Signed-off-by: Steven Whitehouse <swhiteho@redhat.com>
Reported-by: Zheng Liu <gnehzuil.liu@gmail.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Dave Chinner <david@fromorbit.com>
Acked-by: Miklos Szeredi <miklos@szeredi.hu>
Cc: Chris Mason <clm@fb.com>
Cc: Josef Bacik <jbacik@fb.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-01-26 08:26:42 -05:00
Andrew Gallagher 7678ac5061 fuse: support clients that don't implement 'open'
open/release operations require userspace transitions to keep track
of the open count and to perform any FS-specific setup.  However,
for some purely read-only FSs which don't need to perform any setup
at open/release time, we can avoid the performance overhead of
calling into userspace for open/release calls.

This patch adds the necessary support to the fuse kernel modules to prevent
open/release operations from hitting in userspace. When the client returns
ENOSYS, we avoid sending the subsequent release to userspace, and also
remember this so that future opens also don't trigger a userspace
operation.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-01-22 19:36:59 +01:00
Andrew Gallagher 451418fc92 fuse: don't invalidate attrs when not using atime
Various read operations (e.g. readlink, readdir) invalidate the cached
attrs for atime changes.  This patch adds a new function
'fuse_invalidate_atime', which checks for a read-only super block and
avoids the attr invalidation in that case.

Signed-off-by: Andrew Gallagher <andrewjcg@fb.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-01-22 19:36:58 +01:00
Miklos Szeredi 063ec1e595 fuse: fix SetPageUptodate() condition in STORE
As noticed by Coverity the "num != 0" condition never triggers.  Instead it
should check for a complete page.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-01-22 19:36:58 +01:00
Miklos Szeredi 28a625cbc2 fuse: fix pipe_buf_operations
Having this struct in module memory could Oops when if the module is
unloaded while the buffer still persists in a pipe.

Since sock_pipe_buf_ops is essentially the same as fuse_dev_pipe_buf_steal
merge them into nosteal_pipe_buf_ops (this is the same as
default_pipe_buf_ops except stealing the page from the buffer is not
allowed).

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2014-01-22 19:36:57 +01:00
Linus Torvalds 9bc9ccd7db Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs updates from Al Viro:
 "All kinds of stuff this time around; some more notable parts:

   - RCU'd vfsmounts handling
   - new primitives for coredump handling
   - files_lock is gone
   - Bruce's delegations handling series
   - exportfs fixes

  plus misc stuff all over the place"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits)
  ecryptfs: ->f_op is never NULL
  locks: break delegations on any attribute modification
  locks: break delegations on link
  locks: break delegations on rename
  locks: helper functions for delegation breaking
  locks: break delegations on unlink
  namei: minor vfs_unlink cleanup
  locks: implement delegations
  locks: introduce new FL_DELEG lock flag
  vfs: take i_mutex on renamed file
  vfs: rename I_MUTEX_QUOTA now that it's not used for quotas
  vfs: don't use PARENT/CHILD lock classes for non-directories
  vfs: pull ext4's double-i_mutex-locking into common code
  exportfs: fix quadratic behavior in filehandle lookup
  exportfs: better variable name
  exportfs: move most of reconnect_path to helper function
  exportfs: eliminate unused "noprogress" counter
  exportfs: stop retrying once we race with rename/remove
  exportfs: clear DISCONNECTED on all parents sooner
  exportfs: more detailed comment for path_reconnect
  ...
2013-11-13 15:34:18 +09:00
Maxim Patlasov ce128de626 fuse: writepages: protect secondary requests from fuse file release
All async fuse requests must be supplied with extra reference to a fuse
file.  This is necessary to ensure that the fuse file is not released until
all in-flight requests are completed.  Fuse secondary writeback requests
must obey this rule as well.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 10:11:29 +01:00
Maxim Patlasov 41b6e41fc6 fuse: writepages: update bdi writeout when deleting secondary request
BDI_WRITTEN counter is used to estimate bdi bandwidth.  It must be
incremented every time as bdi ends page writeback.  No matter whether it
was fulfilled by actual write or by discarding the request (e.g. due to
shrunk i_size).

Note that even before writepages patches, the case "Got truncated off
completely" was handled in fuse_send_writepage() by calling
fuse_writepage_finish() which updated BDI_WRITTEN unconditionally.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 10:11:28 +01:00
Maxim Patlasov 6eaf4782eb fuse: writepages: crop secondary requests
If writeback happens while fuse is in FUSE_NOWRITE condition, the request
will be queued but not processed immediately (see fuse_flush_writepages()).
Until FUSE_NOWRITE becomes relaxed, more writebacks can happen.  They will
be queued as "secondary" requests to that first ("primary") request.

Existing implementation crops only primary request.  This is not correct
because a subsequent extending write(2) may increase i_size and then
secondary requests won't be cropped properly.  The result would be stale
data written to the server to a file offset where zeros must be.

Similar problem may happen if secondary requests are attached to an
in-flight request that was already cropped.

The patch solves the issue by cropping all secondary requests in
fuse_writepage_end().  Thanks to Miklos for idea.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 10:11:27 +01:00
Maxim Patlasov f6011081f5 fuse: writepages: roll back changes if request not found
fuse_writepage_in_flight() returns false if it fails to find request with
given index in fi->writepages.  Then the caller proceeds with populating
data->orig_pages[] and incrementing req->num_pages.  Hence,
fuse_writepage_in_flight() must revert changes it made in request before
returning false.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-11-05 10:11:26 +01:00
Al Viro dd3e2c55a4 fuse: rcu-delay freeing fuse_conn
makes ->permission() and ->d_revalidate() safety in RCU mode independent
from vfsmount_lock.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-24 23:45:13 -04:00
Miklos Szeredi b70a80e7a1 vfs: introduce d_instantiate_no_diralias()
...which just returns -EBUSY if a directory alias would be created.

This is to be used by fuse mkdir to make sure that a buggy or malicious
userspace filesystem doesn't do anything nasty.  Previously fuse used a
private mutex for this purpose, which can now go away.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-24 23:41:37 -04:00
Tom Gundersen cb2ffb26e6 cuse: add fix minor number to /dev/cuse
This allows udev (or more recently systemd-tmpfiles) to create /dev/cuse on
boot, in the same way as /dev/fuse is currently created, and the corresponding
module to be loaded on first access.

The corresponding functionalty was introduced for fuse in commit 578454f.

Signed-off-by: Tom Gundersen <teg@jklm.no>
Cc: Kay Sievers <kay@vrfy.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:54 +02:00
Miklos Szeredi ff17be0864 fuse: writepage: skip already in flight
If ->writepage() tries to write back a page whose copy is still in flight,
then just skip by calling redirty_page_for_writepage().

This is OK, since now ->writepage() should never be called for data
integrity sync.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
Miklos Szeredi 8b284dc472 fuse: writepages: handle same page rewrites
As Maxim Patlasov pointed out, it's possible to get a dirty page while it's
copy is still under writeback, despite fuse_page_mkwrite() doing its thing
(direct IO).

This could result in two concurrent write request for the same offset, with
data corruption if they get mixed up.

To prevent this, fuse needs to check and delay such writes.  This
implementation does this by:

 1. check if page is still under writeout, if so create a new, single page
    secondary request for it

 2. chain this secondary request onto the in-flight request

 2/a. if a seconday request for the same offset was already chained to the
    in-flight request, then just copy the contents of the page and discard
    the new secondary request.  This makes sure that for each page will
    have at most two requests associated with it

 3. when the in-flight request finished, send off all secondary requests
    chained onto it

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
Miklos Szeredi 1e112a484e fuse: writepages: fix aggregation
Checking against tmp-page indexes is not very useful, and results in one
(or rarely two) page requests.  Which is not much of an improvement...

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
Maxim Patlasov 2d033eaa00 fuse: fix race in fuse_writepages()
The patch fixes a race between ftruncate(2), mmap-ed write and write(2):

1) An user makes a page dirty via mmap-ed write.
2) The user performs shrinking truncate(2) intended to purge the page.
3) Before fuse_do_setattr calls truncate_pagecache, the page goes to
   writeback. fuse_writepages_fill attaches a new page to FUSE_WRITE request,
   then releases the original page by end_page_writeback and unlock it.
4) fuse_do_setattr completes and successfully returns. Since now, i_mutex
   is free.
5) Ordinary write(2) extends i_size back to cover the page. Note that
   fuse_send_write_pages do wait for fuse writeback, but for another
   page->index.
6) fuse_writepages_fill attaches more pages to the request (if any), then
   fuse_writepages_send is eventually called. It is supposed to crop
   inarg->size of the request, but it doesn't because i_size has already been
   extended back.

Moving end_page_writeback behind fuse_writepages_send guarantees that
__fuse_release_nowrite (called from fuse_do_setattr) will crop inarg->size
of the request before write(2) gets the chance to extend i_size.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:53 +02:00
Pavel Emelyanov 26d614df1d fuse: Implement writepages callback
The .writepages one is required to make each writeback request carry more than
one page on it. The patch enables optimized behaviour unconditionally,
i.e. mmap-ed writes will benefit from the patch even if fc->writeback_cache=0.

[SzM: simplify, add comments]

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
Miklos Szeredi 72523425fb fuse: don't BUG on no write file
Don't bug if there's no writable files found for page writeback.  If ever
this is triggered, a WARN_ON helps debugging it much better then a BUG_ON.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:52 +02:00
Miklos Szeredi cca2437045 fuse: lock page in mkwrite
Lock the page in fuse_page_mkwrite() to protect against a race with
fuse_writepage() where the page is redirtied before the actual writeback
begins.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:51 +02:00
Pavel Emelyanov 385b126815 fuse: Prepare to handle multiple pages in writeback
The .writepages callback will issue writeback requests with more than one
page aboard. Make existing end/check code be aware of this.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:51 +02:00
Pavel Emelyanov adcadfa8f3 fuse: Getting file for writeback helper
There will be a .writepageS callback implementation which will need to
get a fuse_file out of a fuse_inode, thus make a helper for this.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Pavel Emelyanov <xemul@openvz.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:44:50 +02:00
Miklos Szeredi 698fa1d163 fuse: no RCU mode in fuse_access()
fuse_access() is never called in RCU walk, only on the final component of
access(2) and chdir(2)...

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-10-01 16:41:23 +02:00
Miklos Szeredi 6314efee3c fuse: readdirplus: fix RCU walk
Doing dput(parent) is not valid in RCU walk mode.  In RCU mode it would
probably be okay to update the parent flags, but it's actually not
necessary most of the time...

So only set the FUSE_I_ADVISE_RDPLUS flag on the parent when the entry was
recently initialized by READDIRPLUS.

This is achieved by setting FUSE_I_INIT_RDPLUS on entries added by
READDIRPLUS and only dropping out of RCU mode if this flag is set.
FUSE_I_INIT_RDPLUS is cleared once the FUSE_I_ADVISE_RDPLUS flag is set in
the parent.

Reported-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2013-10-01 16:41:22 +02:00
Miklos Szeredi 3c70b8eeda fuse: don't check_submounts_and_drop() in RCU walk
If revalidate finds an invalid dentry in RCU walk mode, let the VFS deal
with it instead of calling check_submounts_and_drop() which is not prepared
for being called from RCU walk.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2013-10-01 16:41:22 +02:00
Maxim Patlasov 0ab08f576b fuse: fix fallocate vs. ftruncate race
A former patch introducing FUSE_I_SIZE_UNSTABLE flag provided detailed
description of races between ftruncate and anyone who can extend i_size:

> 1. As in the previous scenario fuse_dentry_revalidate() discovered that i_size
> changed (due to our own fuse_do_setattr()) and is going to call
> truncate_pagecache() for some  'new_size' it believes valid right now. But by
> the time that particular truncate_pagecache() is called ...
> 2. fuse_do_setattr() returns (either having called truncate_pagecache() or
> not -- it doesn't matter).
> 3. The file is extended either by write(2) or ftruncate(2) or fallocate(2).
> 4. mmap-ed write makes a page in the extended region dirty.

This patch adds necessary bits to fuse_file_fallocate() to protect from that
race.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2013-09-18 14:19:59 +02:00
Maxim Patlasov bde52788bd fuse: wait for writeback in fuse_file_fallocate()
The patch fixes a race between mmap-ed write and fallocate(PUNCH_HOLE):

1) An user makes a page dirty via mmap-ed write.
2) The user performs fallocate(2) with mode == PUNCH_HOLE|KEEP_SIZE
   and <offset, size> covering the page.
3) Before truncate_pagecache_range call from fuse_file_fallocate,
   the page goes to write-back. The page is fully processed by fuse_writepage
   (including end_page_writeback on the page), but fuse_flush_writepages did
   nothing because fi->writectr < 0.
4) truncate_pagecache_range is called and fuse_file_fallocate is finishing
   by calling fuse_release_nowrite. The latter triggers processing queued
   write-back request which will write stale data to the hole soon.

Changed in v2 (thanks to Brian for suggestion):
 - Do not truncate page cache until FUSE_FALLOCATE succeeded. Otherwise,
   we can end up in returning -ENOTSUPP while user data is already punched
   from page cache. Use filemap_write_and_wait_range() instead.
Changed in v3 (thanks to Miklos for suggestion):
 - fuse_wait_on_writeback() is prone to livelocks; use fuse_set_nowrite()
   instead. So far as we need a dirty-page barrier only, fuse_sync_writes()
   should be enough.
 - rebased to for-linus branch of fuse.git

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2013-09-18 14:19:59 +02:00
Kirill A. Shutemov 7caef26767 truncate: drop 'oldsize' truncate_pagecache() parameter
truncate_pagecache() doesn't care about old size since commit
cedabed49b ("vfs: Fix vmtruncate() regression").  Let's drop it.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-12 15:38:02 -07:00
Maxim Patlasov 5a53748568 mm/page-writeback.c: add strictlimit feature
The feature prevents mistrusted filesystems (ie: FUSE mounts created by
unprivileged users) to grow a large number of dirty pages before
throttling.  For such filesystems balance_dirty_pages always check bdi
counters against bdi limits.  I.e.  even if global "nr_dirty" is under
"freerun", it's not allowed to skip bdi checks.  The only use case for now
is fuse: it sets bdi max_ratio to 1% by default and system administrators
are supposed to expect that this limit won't be exceeded.

The feature is on if a BDI is marked by BDI_CAP_STRICTLIMIT flag.  A
filesystem may set the flag when it initializes its BDI.

The problematic scenario comes from the fact that nobody pays attention to
the NR_WRITEBACK_TEMP counter (i.e.  number of pages under fuse
writeback).  The implementation of fuse writeback releases original page
(by calling end_page_writeback) almost immediately.  A fuse request queued
for real processing bears a copy of original page.  Hence, if userspace
fuse daemon doesn't finalize write requests in timely manner, an
aggressive mmap writer can pollute virtually all memory by those temporary
fuse page copies.  They are carefully accounted in NR_WRITEBACK_TEMP, but
nobody cares.

To make further explanations shorter, let me use "NR_WRITEBACK_TEMP
problem" as a shortcut for "a possibility of uncontrolled grow of amount
of RAM consumed by temporary pages allocated by kernel fuse to process
writeback".

The problem was very easy to reproduce.  There is a trivial example
filesystem implementation in fuse userspace distribution: fusexmp_fh.c.  I
added "sleep(1);" to the write methods, then recompiled and mounted it.
Then created a huge file on the mount point and run a simple program which
mmap-ed the file to a memory region, then wrote a data to the region.  An
hour later I observed almost all RAM consumed by fuse writeback.  Since
then some unrelated changes in kernel fuse made it more difficult to
reproduce, but it is still possible now.

Putting this theoretical happens-in-the-lab thing aside, there is another
thing that really hurts real world (FUSE) users.  This is write-through
page cache policy FUSE currently uses.  I.e.  handling write(2), kernel
fuse populates page cache and flushes user data to the server
synchronously.  This is excessively suboptimal.  Pavel Emelyanov's patches
("writeback cache policy") solve the problem, but they also make resolving
NR_WRITEBACK_TEMP problem absolutely necessary.  Otherwise, simply copying
a huge file to a fuse mount would result in memory starvation.  Miklos,
the maintainer of FUSE, believes strictlimit feature the way to go.

And eventually putting FUSE topics aside, there is one more use-case for
strictlimit feature.  Using a slow USB stick (mass storage) in a machine
with huge amount of RAM installed is a well-known pain.  Let's make simple
computations.  Assuming 64GB of RAM installed, existing implementation of
balance_dirty_pages will start throttling only after 9.6GB of RAM becomes
dirty (freerun == 15% of total RAM).  So, the command "cp 9GB_file
/media/my-usb-storage/" may return in a few seconds, but subsequent
"umount /media/my-usb-storage/" will take more than two hours if effective
throughput of the storage is, to say, 1MB/sec.

After inclusion of strictlimit feature, it will be trivial to add a knob
(e.g.  /sys/devices/virtual/bdi/x:y/strictlimit) to enable it on demand.
Manually or via udev rule.  May be I'm wrong, but it seems to be quite a
natural desire to limit the amount of dirty memory for some devices we are
not fully trust (in the sense of sustainable throughput).

[akpm@linux-foundation.org: fix warning in page-writeback.c]
Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Cc: Jan Kara <jack@suse.cz>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-09-11 15:58:04 -07:00
Linus Torvalds 16d70e1529 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse bugfixes from Miklos Szeredi:
 "Just a bunch of bugfixes"

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: use list_for_each_entry() for list traversing
  fuse: readdir: check for slash in names
  fuse: hotfix truncate_pagecache() issue
  fuse: invalidate inode attributes on xattr modification
  fuse: postpone end_page_writeback() in fuse_writepage_locked()
2013-09-09 09:18:23 -07:00
Anand Avati 46ea1562da fuse: drop dentry on failed revalidate
Drop a subtree when we find that it has moved or been delated.  This can be
done as long as there are no submounts under this location.

If the directory was moved and we come across the same directory in a
future lookup it will be reconnected by d_materialise_unique().

Signed-off-by: Anand Avati <avati@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-05 16:23:54 -04:00
Miklos Szeredi e2a6b95236 fuse: clean up return in fuse_dentry_revalidate()
On errors unrelated to the filesystem's state (ENOMEM, ENOTCONN) return the
error itself from ->d_revalidate() insted of returning zero (invalid).

Also make a common label for invalidating the dentry.  This will be used by
the next patch.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-05 16:23:54 -04:00
Miklos Szeredi 5835f3390e fuse: use d_materialise_unique()
Use d_materialise_unique() instead of d_splice_alias().  This allows dentry
subtrees to be moved to a new place if there moved, even if something is
referencing a dentry in the subtree (open fd, cwd, etc..).

This will also allow us to drop a subtree if it is found to be replaced by
something else.  In this case the disconnected subtree can later be
reconnected to its new location.

d_materialise_unique() ensures that a directory entry only ever has one
alias.  We keep fc->inst_mutex around the calls for d_materialise_unique()
on directories to prevent a race with mkdir "stealing" the inode.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-09-05 16:23:53 -04:00
Dong Fang 05726acabe fuse: use list_for_each_entry() for list traversing
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-09-04 17:42:42 +02:00
Miklos Szeredi efeb9e60d4 fuse: readdir: check for slash in names
Userspace can add names containing a slash character to the directory
listing.  Don't allow this as it could cause all sorts of trouble.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2013-09-03 14:28:38 +02:00
Maxim Patlasov 06a7c3c278 fuse: hotfix truncate_pagecache() issue
The way how fuse calls truncate_pagecache() from fuse_change_attributes()
is completely wrong. Because, w/o i_mutex held, we never sure whether
'oldsize' and 'attr->size' are valid by the time of execution of
truncate_pagecache(inode, oldsize, attr->size). In fact, as soon as we
released fc->lock in the middle of fuse_change_attributes(), we completely
loose control of actions which may happen with given inode until we reach
truncate_pagecache. The list of potentially dangerous actions includes
mmap-ed reads and writes, ftruncate(2) and write(2) extending file size.

The typical outcome of doing truncate_pagecache() with outdated arguments
is data corruption from user point of view. This is (in some sense)
acceptable in cases when the issue is triggered by a change of the file on
the server (i.e. externally wrt fuse operation), but it is absolutely
intolerable in scenarios when a single fuse client modifies a file without
any external intervention. A real life case I discovered by fsx-linux
looked like this:

1. Shrinking ftruncate(2) comes to fuse_do_setattr(). The latter sends
FUSE_SETATTR to the server synchronously, but before getting fc->lock ...
2. fuse_dentry_revalidate() is asynchronously called. It sends FUSE_LOOKUP
to the server synchronously, then calls fuse_change_attributes(). The
latter updates i_size, releases fc->lock, but before comparing oldsize vs
attr->size..
3. fuse_do_setattr() from the first step proceeds by acquiring fc->lock and
updating attributes and i_size, but now oldsize is equal to
outarg.attr.size because i_size has just been updated (step 2). Hence,
fuse_do_setattr() returns w/o calling truncate_pagecache().
4. As soon as ftruncate(2) completes, the user extends file size by
write(2) making a hole in the middle of file, then reads data from the hole
either by read(2) or mmap-ed read. The user expects to get zero data from
the hole, but gets stale data because truncate_pagecache() is not executed
yet.

The scenario above illustrates one side of the problem: not truncating the
page cache even though we should. Another side corresponds to truncating
page cache too late, when the state of inode changed significantly.
Theoretically, the following is possible:

1. As in the previous scenario fuse_dentry_revalidate() discovered that
i_size changed (due to our own fuse_do_setattr()) and is going to call
truncate_pagecache() for some 'new_size' it believes valid right now. But
by the time that particular truncate_pagecache() is called ...
2. fuse_do_setattr() returns (either having called truncate_pagecache() or
not -- it doesn't matter).
3. The file is extended either by write(2) or ftruncate(2) or fallocate(2).
4. mmap-ed write makes a page in the extended region dirty.

The result will be the lost of data user wrote on the fourth step.

The patch is a hotfix resolving the issue in a simplistic way: let's skip
dangerous i_size update and truncate_pagecache if an operation changing
file size is in progress. This simplistic approach looks correct for the
cases w/o external changes. And to handle them properly, more sophisticated
and intrusive techniques (e.g. NFS-like one) would be required. I'd like to
postpone it until the issue is well discussed on the mailing list(s).

Changed in v2:
 - improved patch description to cover both sides of the issue.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2013-09-03 13:41:58 +02:00
Anand Avati d331a415ae fuse: invalidate inode attributes on xattr modification
Calls like setxattr and removexattr result in updation of ctime.
Therefore invalidate inode attributes to force a refresh.

Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2013-09-03 13:41:58 +02:00
Maxim Patlasov 4a4ac4eba1 fuse: postpone end_page_writeback() in fuse_writepage_locked()
The patch fixes a race between ftruncate(2), mmap-ed write and write(2):

1) An user makes a page dirty via mmap-ed write.
2) The user performs shrinking truncate(2) intended to purge the page.
3) Before fuse_do_setattr calls truncate_pagecache, the page goes to
   writeback. fuse_writepage_locked fills FUSE_WRITE request and releases
   the original page by end_page_writeback.
4) fuse_do_setattr() completes and successfully returns. Since now, i_mutex
   is free.
5) Ordinary write(2) extends i_size back to cover the page. Note that
   fuse_send_write_pages do wait for fuse writeback, but for another
   page->index.
6) fuse_writepage_locked proceeds by queueing FUSE_WRITE request.
   fuse_send_writepage is supposed to crop inarg->size of the request,
   but it doesn't because i_size has already been extended back.

Moving end_page_writeback to the end of fuse_writepage_locked fixes the
race because now the fact that truncate_pagecache is successfully returned
infers that fuse_writepage_locked has already called end_page_writeback.
And this, in turn, infers that fuse_flush_writepages has already called
fuse_send_writepage, and the latter used valid (shrunk) i_size. write(2)
could not extend it because of i_mutex held by ftruncate(2).

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2013-09-03 13:41:57 +02:00
Greg Kroah-Hartman b78b6b3a9a Merge 3.11-rc3 into driver-core-next
We want these fixes in this branch.

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-29 12:30:13 -07:00
Greg Kroah-Hartman 4183fb9503 cuse: convert class code to use dev_groups
The dev_attrs field of struct class is going away soon, dev_groups
should be used instead.  This converts the cuse class code to use the
correct field.

Acked-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-07-26 18:05:18 -07:00
Miklos Szeredi c7263bcdc4 fuse: readdirplus: cleanup
Niels noted that we don't need the 'dentry = NULL' line.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Niels de Vos <ndevos@redhat.com>
2013-07-17 14:53:54 +02:00
Miklos Szeredi fa2b721360 fuse: readdirplus: change attributes once
If we got the inode through fuse_iget() then the attributes are already
up-to-date.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-07-17 14:53:53 +02:00
Miklos Szeredi 2914941e31 fuse: readdirplus: fix instantiate
Fuse does instantiation slightly differently from NFS/CIFS which use
d_materialise_unique().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@vger.kernel.org
2013-07-17 14:53:53 +02:00
Miklos Szeredi a28ef45cbb fuse: readdirplus: sanity checks
Add sanity checks before adding or updating an entry with data received
from readdirplus.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@vger.kernel.org
2013-07-17 14:53:53 +02:00
Niels de Vos 53ce9a3364 fuse: readdirplus: fix dentry leak
In case d_lookup() returns a dentry with d_inode == NULL, the dentry is not
returned with dput(). This results in triggering a BUG() in
shrink_dcache_for_umount_subtree():

  BUG: Dentry ...{i=0,n=...} still in use (1) [unmount of fuse fuse]

[SzM: need to d_drop() as well]

Reported-by: Justin Clift <jclift@redhat.com>
Signed-off-by: Niels de Vos <ndevos@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Brian Foster <bfoster@redhat.com>
Tested-by: Niels de Vos <ndevos@redhat.com>
CC: stable@vger.kernel.org
2013-07-17 14:53:53 +02:00
Jiang Liu 0ed5fd1385 mm: use totalram_pages instead of num_physpages at runtime
The global variable num_physpages is scheduled to be removed, so use
totalram_pages instead of num_physpages at runtime.

Signed-off-by: Jiang Liu <jiang.liu@huawei.com>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Alexey Kuznetsov <kuznet@ms2.inr.ac.ru>
Cc: James Morris <jmorris@namei.org>
Cc: Hideaki YOSHIFUJI <yoshfuji@linux-ipv6.org>
Cc: Patrick McHardy <kaber@trash.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-07-03 16:07:35 -07:00
Linus Torvalds 790eac5640 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull second set of VFS changes from Al Viro:
 "Assorted f_pos race fixes, making do_splice_direct() safe to call with
  i_mutex on parent, O_TMPFILE support, Jeff's locks.c series,
  ->d_hash/->d_compare calling conventions changes from Linus, misc
  stuff all over the place."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (63 commits)
  Document ->tmpfile()
  ext4: ->tmpfile() support
  vfs: export lseek_execute() to modules
  lseek_execute() doesn't need an inode passed to it
  block_dev: switch to fixed_size_llseek()
  cpqphp_sysfs: switch to fixed_size_llseek()
  tile-srom: switch to fixed_size_llseek()
  proc_powerpc: switch to fixed_size_llseek()
  ubi/cdev: switch to fixed_size_llseek()
  pci/proc: switch to fixed_size_llseek()
  isapnp: switch to fixed_size_llseek()
  lpfc: switch to fixed_size_llseek()
  locks: give the blocked_hash its own spinlock
  locks: add a new "lm_owner_key" lock operation
  locks: turn the blocked_list into a hashtable
  locks: convert fl_link to a hlist_node
  locks: avoid taking global lock if possible when waking up blocked waiters
  locks: protect most of the file_lock handling with i_lock
  locks: encapsulate the fl_link list handling
  locks: make "added" in __posix_lock_file a bool
  ...
2013-07-03 09:10:19 -07:00
Linus Torvalds 63580e51bb Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull VFS patches (part 1) from Al Viro:
 "The major change in this pile is ->readdir() replacement with
  ->iterate(), dealing with ->f_pos races in ->readdir() instances for
  good.

  There's a lot more, but I'd prefer to split the pull request into
  several stages and this is the first obvious cutoff point."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (67 commits)
  [readdir] constify ->actor
  [readdir] ->readdir() is gone
  [readdir] convert ecryptfs
  [readdir] convert coda
  [readdir] convert ocfs2
  [readdir] convert fatfs
  [readdir] convert xfs
  [readdir] convert btrfs
  [readdir] convert hostfs
  [readdir] convert afs
  [readdir] convert ncpfs
  [readdir] convert hfsplus
  [readdir] convert hfs
  [readdir] convert befs
  [readdir] convert cifs
  [readdir] convert freevxfs
  [readdir] convert fuse
  [readdir] convert hpfs
  reiserfs: switch reiserfs_readdir_dentry to inode
  reiserfs: is_privroot_deh() needs only directory inode, actually
  ...
2013-07-02 09:28:37 -07:00
Al Viro cb5e05d1a6 fuse: another open-coded file_inode()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:57:24 +04:00
Al Viro 8d3af7f333 [readdir] convert fuse
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-06-29 12:56:52 +04:00
Maxim Patlasov 14c14414d1 fuse: hold i_mutex in fuse_file_fallocate()
Changing size of a file on server and local update (fuse_write_update_size)
should be always protected by inode->i_mutex. Otherwise a race like this is
possible:

1. Process 'A' calls fallocate(2) to extend file (~FALLOC_FL_KEEP_SIZE).
fuse_file_fallocate() sends FUSE_FALLOCATE request to the server.
2. Process 'B' calls ftruncate(2) shrinking the file. fuse_do_setattr()
sends shrinking FUSE_SETATTR request to the server and updates local i_size
by i_size_write(inode, outarg.attr.size).
3. Process 'A' resumes execution of fuse_file_fallocate() and calls
fuse_write_update_size(inode, offset + length). But 'offset + length' was
obsoleted by ftruncate from previous step.

Changed in v2 (thanks Brian and Anand for suggestions):
 - made relation between mutex_lock() and fuse_set_nowrite(inode) more
   explicit and clear.
 - updated patch description to use ftruncate(2) in example

Signed-off-by: Maxim V. Patlasov <MPatlasov@parallels.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-18 01:39:03 +02:00
Maxim Patlasov e5c5f05dca fuse: fix alignment in short read optimization for async_dio
The bug was introduced with async_dio feature: trying to optimize short reads,
we cut number-of-bytes-to-read to i_size boundary. Hence the following example:

	truncate --size=300 /mnt/file
	dd if=/mnt/file of=/dev/null iflag=direct

led to FUSE_READ request of 300 bytes size. This turned out to be problem
for userspace fuse implementations who rely on assumption that kernel fuse
does not change alignment of request from client FS.

The patch turns off the optimization if async_dio is disabled. And, if it's
enabled, the patch fixes adjustment of number-of-bytes-to-read to preserve
alignment.

Note, that we cannot throw out short read optimization entirely because
otherwise a direct read of a huge size issued on a tiny file would generate
a huge amount of fuse requests and most of them would be ACKed by userspace
with zero bytes read.

Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-03 15:15:42 +02:00
Brian Foster c9ecf989cc fuse: return -EIOCBQUEUED from fuse_direct_IO() for all async requests
If request submission fails for an async request (i.e.,
get_user_pages() returns -ERESTARTSYS), we currently skip the
-EIOCBQUEUED return and drop into wait_for_sync_kiocb() forever.

Avoid this by always returning -EIOCBQUEUED for async requests. If
an error occurs, the error is passed into fuse_aio_complete(),
returned via aio_complete() and thus propagated to userspace via
io_getevents().

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Maxim Patlasov <MPatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-06-03 15:15:42 +02:00
Miklos Szeredi 28420dad23 fuse: fix readdirplus Oops in fuse_dentry_revalidate
Fix bug introduced by commit 4582a4ab2a "FUSE: Adapt readdirplus to application
usage patterns".

We need to check for a positive dentry; negative dentries are not added by
readdirplus.  Secondly we need to advise the use of readdirplus on the *parent*,
otherwise the whole thing is useless.  Thirdly all this is only relevant if
"readdirplus_auto" mode is selected by the filesystem.

We advise the use of readdirplus only if the dentry was still valid.  If we had
to redo the lookup then there was no use in doing the -plus version.

Reported-by: Bernd Schubert <bernd.schubert@itwm.fraunhofer.de>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: Feng Shuo <steve.shuo.feng@gmail.com>
CC: stable@vger.kernel.org
2013-06-03 14:40:22 +02:00
Brian Foster bee6c30780 fuse: update inode size and invalidate attributes on fallocate
An fallocate request without FALLOC_FL_KEEP_SIZE set can extend the
size of a file. Update the inode size after a successful fallocate.

Also invalidate the inode attributes after a successful fallocate
to ensure we pick up the latest attribute values (i.e., i_blocks).

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-20 16:58:58 +02:00
Brian Foster 3634a63278 fuse: truncate pagecache range on hole punch
fuse supports hole punch via the fallocate() FALLOC_FL_PUNCH_HOLE
interface. When a hole punch is passed through, the page cache
is not cleared and thus allows reading stale data from the cache.

This is easily demonstrable (using FOPEN_KEEP_CACHE) by reading a
smallish random data file into cache, punching a hole and creating
a copy of the file. Drop caches or remount and observe that the
original file no longer matches the file copied after the hole
punch. The original file contains a zeroed range and the latter
file contains stale data.

Protect against writepage requests in progress and punch out the
associated page cache range after a successful client fs hole
punch.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-20 16:58:57 +02:00
Brian Foster de82b92301 fuse: allocate for_background dio requests based on io->async state
Commit 8b41e671 introduced explicit background checking for fuse_req
structures with BUG_ON() checks for the appropriate type of request in
in the associated send functions. Commit bcba24cc introduced the ability
to send dio requests as background requests but does not update the
request allocation based on the type of I/O request. As a result, a
BUG_ON() triggers in the fuse_request_send_background() background path if
an async I/O is sent.

Allocate a request based on the async state of the fuse_io_priv to avoid
the BUG.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-14 18:25:44 +02:00
Linus Torvalds 5af43c24ca Merge branch 'akpm' (incoming from Andrew)
Merge more incoming from Andrew Morton:

 - Various fixes which were stalled or which I picked up recently

 - A large rotorooting of the AIO code.  Allegedly to improve
   performance but I don't really have good performance numbers (I might
   have lost the email) and I can't raise Kent today.  I held this out
   of 3.9 and we could give it another cycle if it's all too late/scary.

I ended up taking only the first two thirds of the AIO rotorooting.  I
left the percpu parts and the batch completion for later.  - Linus

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (33 commits)
  aio: don't include aio.h in sched.h
  aio: kill ki_retry
  aio: kill ki_key
  aio: give shared kioctx fields their own cachelines
  aio: kill struct aio_ring_info
  aio: kill batch allocation
  aio: change reqs_active to include unreaped completions
  aio: use cancellation list lazily
  aio: use flush_dcache_page()
  aio: make aio_read_evt() more efficient, convert to hrtimers
  wait: add wait_event_hrtimeout()
  aio: refcounting cleanup
  aio: make aio_put_req() lockless
  aio: do fget() after aio_get_req()
  aio: dprintk() -> pr_debug()
  aio: move private stuff out of aio.h
  aio: add kiocb_cancel()
  aio: kill return value of aio_complete()
  char: add aio_{read,write} to /dev/{null,zero}
  aio: remove retry-based AIO
  ...
2013-05-07 20:49:51 -07:00
Kent Overstreet a27bb332c0 aio: don't include aio.h in sched.h
Faster kernel compiles by way of fewer unnecessary includes.

[akpm@linux-foundation.org: fix fallout]
[akpm@linux-foundation.org: fix build]
Signed-off-by: Kent Overstreet <koverstreet@google.com>
Cc: Zach Brown <zab@redhat.com>
Cc: Felipe Balbi <balbi@ti.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <jlbec@evilplan.org>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Asai Thambi S P <asamymuthupa@micron.com>
Cc: Selvan Mani <smani@micron.com>
Cc: Sam Bradshaw <sbradshaw@micron.com>
Cc: Jeff Moyer <jmoyer@redhat.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Benjamin LaHaise <bcrl@kvack.org>
Reviewed-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-05-07 20:16:25 -07:00
Linus Torvalds a26ea93a3d Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi:
 "This contains two patchsets from Maxim Patlasov.

  The first reworks the request throttling so that only async requests
  are throttled.  Wakeup of waiting async requests is also optimized.

  The second series adds support for async processing of direct IO which
  optimizes direct IO and enables the use of the AIO userspace
  interface."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: add flag to turn on async direct IO
  fuse: truncate file if async dio failed
  fuse: optimize short direct reads
  fuse: enable asynchronous processing direct IO
  fuse: make fuse_direct_io() aware about AIO
  fuse: add support of async IO
  fuse: move fuse_release_user_pages() up
  fuse: optimize wake_up
  fuse: implement exclusive wakeup for blocked_waitq
  fuse: skip blocking on allocations of synchronous requests
  fuse: add flag fc->initialized
  fuse: make request allocations for background processing explicit
2013-05-07 10:12:32 -07:00
Miklos Szeredi 60b9df7a54 fuse: add flag to turn on async direct IO
Without async DIO write requests to a single file were always serialized.
With async DIO that's no longer the case.

So don't turn on async DIO by default for fear of breaking backward
compatibility.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-05-01 14:37:21 +02:00
Maxim Patlasov efb9fa9e91 fuse: truncate file if async dio failed
The patch improves error handling in fuse_direct_IO(): if we successfully
submitted several fuse requests on behalf of synchronous direct write
extending file and some of them failed, let's try to do our best to clean-up.

Changed in v2: reuse fuse_do_setattr(). Thanks to Brian for suggestion.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-18 10:55:24 +02:00
Maxim Patlasov 439ee5f0c5 fuse: optimize short direct reads
If user requested direct read beyond EOF, we can skip sending fuse requests
for positions beyond EOF because userspace would ACK them with zero bytes read
anyway. We can trust to i_size in fuse_direct_IO for such cases because it's
called from fuse_file_aio_read() and the latter updates fuse attributes
including i_size.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 21:50:59 +02:00
Maxim Patlasov bcba24ccdc fuse: enable asynchronous processing direct IO
In case of synchronous DIO request (i.e. read(2) or write(2) for a file
opened with O_DIRECT), the patch submits fuse requests asynchronously, but
waits for their completions before return from fuse_direct_IO().

In case of asynchronous DIO request (i.e. libaio io_submit() or a file opened
with O_DIRECT), the patch submits fuse requests asynchronously and return
-EIOCBQUEUED immediately.

The only special case is async DIO extending file. Here the patch falls back
to old behaviour because we can't return -EIOCBQUEUED and update i_size later,
without i_mutex hold. And we have no method to wait on real async I/O
requests.

The patch also clean __fuse_direct_write() up: it's better to update i_size
in its callers. Thanks Brian for suggestion.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 21:50:59 +02:00
Maxim Patlasov 36cf66ed9f fuse: make fuse_direct_io() aware about AIO
The patch implements passing "struct fuse_io_priv *io" down the stack up to
fuse_send_read/write where it is used to submit request asynchronously.
io->async==0 designates synchronous processing.

Non-trivial part of the patch is changes in fuse_direct_io(): resources
like fuse requests and user pages cannot be released immediately in async
case.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 21:50:59 +02:00
Maxim Patlasov 01e9d11a3e fuse: add support of async IO
The patch implements a framework to process an IO request asynchronously. The
idea is to associate several fuse requests with a single kiocb by means of
fuse_io_priv structure. The structure plays the same role for FUSE as 'struct
dio' for direct-io.c.

The framework is supposed to be used like this:
 - someone (who wants to process an IO asynchronously) allocates fuse_io_priv
   and initializes it setting 'async' field to non-zero value.
 - as soon as fuse request is filled, it can be submitted (in non-blocking way)
   by fuse_async_req_send()
 - when all submitted requests are ACKed by userspace, io->reqs drops to zero
   triggering aio_complete()

In case of IO initiated by libaio, aio_complete() will finish processing the
same way as in case of dio_complete() calling aio_complete(). But the
framework may be also used for internal FUSE use when initial IO request
was synchronous (from user perspective), but it's beneficial to process it
asynchronously. Then the caller should wait on kiocb explicitly and
aio_complete() will wake the caller up.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 21:50:59 +02:00
Maxim Patlasov 187c5c3633 fuse: move fuse_release_user_pages() up
fuse_release_user_pages() will be indirectly used by fuse_send_read/write
in future patches.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 21:50:58 +02:00
Miklos Szeredi 3c18ef8117 fuse: optimize wake_up
Normally blocked_waitq will be inactive, so optimize this case.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 21:50:58 +02:00
Maxim Patlasov 722d2bea8c fuse: implement exclusive wakeup for blocked_waitq
The patch solves thundering herd problem. So far as previous patches ensured
that only allocations for background may block, it's safe to wake up one
waiter. Whoever it is, it will wake up another one in request_end() afterwards.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 12:31:45 +02:00
Maxim Patlasov 0aada88476 fuse: skip blocking on allocations of synchronous requests
A task may have at most one synchronous request allocated. So these
requests need not be otherwise limited.

The patch re-works fuse_get_req() to follow this idea.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 12:31:45 +02:00
Maxim Patlasov 796523fb24 fuse: add flag fc->initialized
Existing flag fc->blocked is used to suspend request allocation both in case
of many background request submitted and period of time before init_reply
arrives from userspace. Next patch will skip blocking allocations of
synchronous request (disregarding fc->blocked). This is mostly OK, but
we still need to suspend allocations if init_reply is not arrived yet. The
patch introduces flag fc->initialized which will serve this purpose.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 12:31:44 +02:00
Maxim Patlasov 8b41e6715e fuse: make request allocations for background processing explicit
There are two types of processing requests in FUSE: synchronous (via
fuse_request_send()) and asynchronous (via adding to fc->bg_queue).

Fortunately, the type of processing is always known in advance, at the time
of request allocation. This preparatory patch utilizes this fact making
fuse_get_req() aware about the type. Next patches will use it.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17 12:31:44 +02:00
Al Viro 6447a3cf19 get rid of pipe->inode
it's used only as a flag to distinguish normal pipes/FIFOs from the
internal per-task one used by file-to-file splice.  And pipe->files
would work just as well for that purpose...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-09 14:13:01 -04:00
Al Viro 8d71db4f08 lift sb_start_write/sb_end_write out of ->aio_write()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-04-09 14:12:55 -04:00
Eric W. Biederman 7f78e03513 fs: Limit sys_mount to only request filesystem modules.
Modify the request_module to prefix the file system type with "fs-"
and add aliases to all of the filesystems that can be built as modules
to match.

A common practice is to build all of the kernel code and leave code
that is not commonly needed as modules, with the result that many
users are exposed to any bug anywhere in the kernel.

Looking for filesystems with a fs- prefix limits the pool of possible
modules that can be loaded by mount to just filesystems trivially
making things safer with no real cost.

Using aliases means user space can control the policy of which
filesystem modules are auto-loaded by editing /etc/modprobe.d/*.conf
with blacklist and alias directives.  Allowing simple, safe,
well understood work-arounds to known problematic software.

This also addresses a rare but unfortunate problem where the filesystem
name is not the same as it's module name and module auto-loading
would not work.  While writing this patch I saw a handful of such
cases.  The most significant being autofs that lives in the module
autofs4.

This is relevant to user namespaces because we can reach the request
module in get_fs_type() without having any special permissions, and
people get uncomfortable when a user specified string (in this case
the filesystem type) goes all of the way to request_module.

After having looked at this issue I don't think there is any
particular reason to perform any filtering or permission checks beyond
making it clear in the module request that we want a filesystem
module.  The common pattern in the kernel is to call request_module()
without regards to the users permissions.  In general all a filesystem
module does once loaded is call register_filesystem() and go to sleep.
Which means there is not much attack surface exposed by loading a
filesytem module unless the filesystem is mounted.  In a user
namespace filesystems are not mounted unless .fs_flags = FS_USERNS_MOUNT,
which most filesystems do not set today.

Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Acked-by: Kees Cook <keescook@chromium.org>
Reported-by: Kees Cook <keescook@google.com>
Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
2013-03-03 19:36:31 -08:00
Al Viro 6131ffaa1f more file_inode() open-coded instances
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-27 16:59:05 -05:00
Linus Torvalds d895cb1af1 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile (part one) from Al Viro:
 "Assorted stuff - cleaning namei.c up a bit, fixing ->d_name/->d_parent
  locking violations, etc.

  The most visible changes here are death of FS_REVAL_DOT (replaced with
  "has ->d_weak_revalidate()") and a new helper getting from struct file
  to inode.  Some bits of preparation to xattr method interface changes.

  Misc patches by various people sent this cycle *and* ocfs2 fixes from
  several cycles ago that should've been upstream right then.

  PS: the next vfs pile will be xattr stuff."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (46 commits)
  saner proc_get_inode() calling conventions
  proc: avoid extra pde_put() in proc_fill_super()
  fs: change return values from -EACCES to -EPERM
  fs/exec.c: make bprm_mm_init() static
  ocfs2/dlm: use GFP_ATOMIC inside a spin_lock
  ocfs2: fix possible use-after-free with AIO
  ocfs2: Fix oops in ocfs2_fast_symlink_readpage() code path
  get_empty_filp()/alloc_file() leave both ->f_pos and ->f_version zero
  target: writev() on single-element vector is pointless
  export kernel_write(), convert open-coded instances
  fs: encode_fh: return FILEID_INVALID if invalid fid_type
  kill f_vfsmnt
  vfs: kill FS_REVAL_DOT by adding a d_weak_revalidate dentry op
  nfsd: handle vfs_getattr errors in acl protocol
  switch vfs_getattr() to struct path
  default SET_PERSONALITY() in linux/elf.h
  ceph: prepopulate inodes only when request is aborted
  d_hash_and_lookup(): export, switch open-coded instances
  9p: switch v9fs_set_create_acl() to inode+fid, do it before d_instantiate()
  9p: split dropping the acls from v9fs_set_create_acl()
  ...
2013-02-26 20:16:07 -08:00
Namjae Jeon 94e07a7590 fs: encode_fh: return FILEID_INVALID if invalid fid_type
This patch is a follow up on below patch:

[PATCH] exportfs: add FILEID_INVALID to indicate invalid fid_type
commit: 216b6cbdcb

Signed-off-by: Namjae Jeon <namjae.jeon@samsung.com>
Signed-off-by: Vivek Trivedi <t.vivek@samsung.com>
Acked-by: Steven Whitehouse <swhiteho@redhat.com>
Acked-by: Sage Weil <sage@inktank.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-26 02:46:10 -05:00
Al Viro 496ad9aa8e new helper: file_inode(file)
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-02-22 23:31:31 -05:00
Eric Wong 634734b63a fuse: allow control of adaptive readdirplus use
For some filesystems (e.g. GlusterFS), the cost of performing a
normal readdir and readdirplus are identical.  Since adaptively
using readdirplus has no benefit for those systems, give
users/filesystems the option to control adaptive readdirplus use.

v2 of this patch incorporates Miklos's suggestion to simplify the code,
as well as improving consistency of macro names and documentation.

Signed-off-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-02-07 14:25:44 +01:00
Enke Chen 0415d29102 fuse: send poll events
commit 626cf23660 "poll: add poll_requested_events()..." enabled us to send the
requested events to the filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-02-04 16:14:32 +01:00
Miklos Szeredi dfca7cebc2 fuse: don't WARN when nlink is zero
drop_nlink() warns if nlink is already zero.  This is triggerable by a buggy
userspace filesystem.  The cure, I think, is worse than the disease so disable
the warning.

Reported-by: Tero Roponen <tero.roponen@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-02-04 15:57:42 +01:00
Eric Wong 6a4e922c3d fuse: avoid out-of-scope stack access
The all pointers within fuse_req must point to valid memory once
fuse_force_forget() returns.

This bug appeared in "fuse: implement NFS-like readdirplus support"
and was never in any official Linux release.

I tested the fuse_force_forget() code path by injecting to fake -ENOMEM and
verified the FORGET operation was called properly in userspace.

Signed-off-by: Eric Wong <normalperson@yhbt.net>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-02-04 15:22:23 +01:00
Feng Shuo 4582a4ab2a FUSE: Adapt readdirplus to application usage patterns
Use the same adaptive readdirplus mechanism as NFS:

http://permalink.gmane.org/gmane.linux.nfs/49299

If the user space implementation wants to disable readdirplus
temporarily, it could just return ENOTSUPP. Then kernel will
recall it with readdir.

Signed-off-by: Feng Shuo <steve.shuo.feng@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-31 17:08:11 +01:00
Anatol Pomozov c2132c1bc7 Do not use RCU for current process credentials
Commit c69e8d9c0 added rcu lock to fuse/dir.c It was assuming
that 'task' is some other process but in fact this parameter always
equals to 'current'. Inline this parameter to make it more readable
and remove RCU lock as it is not needed when access current process
credentials.

Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-31 17:08:10 +01:00
Miklos Szeredi fb05f41f5f fuse: cleanup fuse_direct_io()
Fix the following sparse warnings:

fs/fuse/file.c:1216:43: warning: cast removes address space of expression
fs/fuse/file.c:1216:43: warning: incorrect type in initializer (different address spaces)
fs/fuse/file.c:1216:43:    expected void [noderef] <asn:1>*iov_base
fs/fuse/file.c:1216:43:    got void *<noident>
fs/fuse/file.c:1241:43: warning: cast removes address space of expression
fs/fuse/file.c:1241:43: warning: incorrect type in initializer (different address spaces)
fs/fuse/file.c:1241:43:    expected void [noderef] <asn:1>*iov_base
fs/fuse/file.c:1241:43:    got void *<noident>
fs/fuse/file.c:1267:43: warning: cast removes address space of expression
fs/fuse/file.c:1267:43: warning: incorrect type in initializer (different address spaces)
fs/fuse/file.c:1267:43:    expected void [noderef] <asn:1>*iov_base
fs/fuse/file.c:1267:43:    got void *<noident>

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:28 +01:00
Maxim Patlasov 5565a9d884 fuse: optimize __fuse_direct_io()
__fuse_direct_io() allocates fuse-requests by calling fuse_get_req(fc, n). The
patch calculates 'n' based on iov[] array. This is useful because allocating
FUSE_MAX_PAGES_PER_REQ page pointers and descriptors for each fuse request
would be waste of memory in case of iov-s of smaller size.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:28 +01:00
Maxim Patlasov 7c190c8b9c fuse: optimize fuse_get_user_pages()
Let fuse_get_user_pages() pack as many iov-s to a single fuse_req as
possible. This is very beneficial in case of iov[] consisting of many
iov-s of relatively small sizes (e.g. PAGE_SIZE).

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:27 +01:00
Maxim Patlasov b98d023a24 fuse: pass iov[] to fuse_get_user_pages()
The patch makes preliminary work for the next patch optimizing scatter-gather
direct IO. The idea is to allow fuse_get_user_pages() to pack as many iov-s
to each fuse request as possible. So, here we only rework all related
call-paths to carry iov[] from fuse_direct_IO() to fuse_get_user_pages().

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:27 +01:00
Maxim Patlasov 85f40aec88 fuse: use req->page_descs[] for argpages cases
Previously, anyone who set flag 'argpages' only filled req->pages[] and set
per-request page_offset. This patch re-works all cases where argpages=1 to
fill req->page_descs[] properly.

Having req->page_descs[] filled properly allows to re-work fuse_copy_pages()
to copy page fragments described by req->page_descs[]. This will be useful
for next patches optimizing direct_IO.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:27 +01:00
Maxim Patlasov b2430d7567 fuse: add per-page descriptor <offset, length> to fuse_req
The ability to save page pointers along with lengths and offsets in fuse_req
will be useful to cover several iovec-s with a single fuse_req.

Per-request page_offset is removed because anybody who need it can use
req->page_descs[0].offset instead.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:27 +01:00
Maxim Patlasov 54b966702d fuse: rework fuse_do_ioctl()
fuse_do_ioctl() already calculates the number of pages it's going to use. It is
stored in 'num_pages' variable. So the patch simply uses it for allocating
fuse_req.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:26 +01:00
Maxim Patlasov d07f09f509 fuse: rework fuse_perform_write()
The patch allocates as many page pointers in fuse_req as needed to cover
interval [pos .. pos+len-1]. Inline helper fuse_wr_pages() is introduced
to hide this cumbersome arithmetic.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:26 +01:00
Maxim Patlasov f8dbdf8182 fuse: rework fuse_readpages()
The patch uses 'nr_pages' argument of fuse_readpages() as heuristics for the
number of page pointers to allocate.

This can be improved further by taking in consideration fc->max_read and gaps
between page indices, but it's not clear whether it's worthy or not.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:26 +01:00
Maxim Patlasov 4d53dc99ba fuse: rework fuse_retrieve()
The patch reworks fuse_retrieve() to allocate only so many page pointers
as needed. The core part of the patch is the following calculation:

	num_pages = (num + offset + PAGE_SIZE - 1) >> PAGE_SHIFT;

(thanks Miklos for formula). All other changes are mostly shuffling lines.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:26 +01:00
Maxim Patlasov b111c8c0e3 fuse: categorize fuse_get_req()
The patch categorizes all fuse_get_req() invocations into two categories:
 - fuse_get_req_nopages(fc) - when caller doesn't care about req->pages
 - fuse_get_req(fc, n) - when caller need n page pointers (n > 0)

Adding fuse_get_req_nopages() helps to avoid numerous fuse_get_req(fc, 0)
scattered over code. Now it's clear from the first glance when a caller need
fuse_req with page pointers.

The patch doesn't make any logic changes. In multi-page case, it silly
allocates array of FUSE_MAX_PAGES_PER_REQ page pointers. This will be amended
by future patches.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:25 +01:00
Maxim Patlasov 4250c0668e fuse: general infrastructure for pages[] of variable size
The patch removes inline array of FUSE_MAX_PAGES_PER_REQ page pointers from
fuse_req. Instead of that, req->pages may now point either to small inline
array or to an array allocated dynamically.

This essentially means that all callers of fuse_request_alloc[_nofs] should
pass the number of pages needed explicitly.

The patch doesn't make any logic changes.

Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:25 +01:00
Anand V. Avati 0b05b18381 fuse: implement NFS-like readdirplus support
This patch implements readdirplus support in FUSE, similar to NFS.
The payload returned in the readdirplus call contains
'fuse_entry_out' structure thereby providing all the necessary inputs
for 'faking' a lookup() operation on the spot.

If the dentry and inode already existed (for e.g. in a re-run of ls -l)
then just the inode attributes timeout and dentry timeout are refreshed.

With a simple client->network->server implementation of a FUSE based
filesystem, the following performance observations were made:

Test: Performing a filesystem crawl over 20,000 files with

sh# time ls -lR /mnt

Without readdirplus:
Run 1: 18.1s
Run 2: 16.0s
Run 3: 16.2s

With readdirplus:
Run 1: 4.1s
Run 2: 3.8s
Run 3: 3.8s

The performance improvement is significant as it avoided 20,000 upcalls
calls (lookup). Cache consistency is no worse than what already is.

Signed-off-by: Anand V. Avati <avati@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24 16:21:25 +01:00
Wei Yongjun 8f706111a8 fuse: remove unused variable in fuse_try_move_page()
The variables mapping,index are initialized but never used
otherwise, so remove the unused variables.

dpatch engine is used to auto generate this patch.
(https://github.com/weiyj/dpatch)

Signed-off-by: Wei Yongjun <yongjun_wei@trendmicro.com.cn>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17 13:09:59 +01:00
Miklos Szeredi cdadb11cef fuse: make fuse_file_fallocate() static
Fix the following sparse warning:

fs/fuse/file.c:2249:6: warning: symbol 'fuse_file_fallocate' was not declared. Should it be static?

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17 13:09:47 +01:00
Robert P. J. Day 807185eb3e fuse: Move CUSE Kconfig entry from fs/Kconfig into fs/fuse/Kconfig
Given that CUSE depends on FUSE, it only makes sense to move its
Kconfig entry into the FUSE Kconfig file.  Also, add a few grammatical
and semantic touchups.

Signed-off-by: Robert P. J. Day <rpjday@crashcourse.ca>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17 13:08:45 +01:00
Miklos Szeredi e2560362cc cuse: fix uninitialized variable warnings
Fix the following compiler warnings:

fs/fuse/cuse.c: In function 'cuse_process_init_reply':
fs/fuse/cuse.c:288:24: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized]
fs/fuse/cuse.c:272:14: note: 'val' was declared here
fs/fuse/cuse.c:284:10: warning: 'key' may be used uninitialized in this function [-Wmaybe-uninitialized]
fs/fuse/cuse.c:272:8: note: 'key' was declared here

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17 13:05:52 +01:00
David Herrmann 30783587b0 cuse: do not register multiple devices with identical names
Sysfs doesn't allow two devices with the same name, but we register a
sysfs entry for each cuse device without checking for name collisions.
This extends the registration to first check whether the name was already
registered.

To avoid race-conditions between the name-check and linking the device, we
need to protect the whole registration with a mutex.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17 13:04:57 +01:00
David Herrmann 8ce03fd76d cuse: use mutex as registration lock instead of spinlocks
We need to check for name-collisions during cuse-device registration. To
avoid race-conditions, this needs to be protected during the whole device
registration. Therefore, replace the spinlocks by mutexes first so we can
safely extend the locked regions to include more expensive or sleeping
code paths.

Signed-off-by: David Herrmann <dh.herrmann@googlemail.com>
Acked-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17 13:04:51 +01:00
Linus Torvalds 848b81415c Merge branch 'akpm' (Andrew's patch-bomb)
Merge misc patches from Andrew Morton:
 "Incoming:

   - lots of misc stuff

   - backlight tree updates

   - lib/ updates

   - Oleg's percpu-rwsem changes

   - checkpatch

   - rtc

   - aoe

   - more checkpoint/restart support

  I still have a pile of MM stuff pending - Pekka should be merging
  later today after which that is good to go.  A number of other things
  are twiddling thumbs awaiting maintainer merges."

* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (180 commits)
  scatterlist: don't BUG when we can trivially return a proper error.
  docs: update documentation about /proc/<pid>/fdinfo/<fd> fanotify output
  fs, fanotify: add @mflags field to fanotify output
  docs: add documentation about /proc/<pid>/fdinfo/<fd> output
  fs, notify: add procfs fdinfo helper
  fs, exportfs: add exportfs_encode_inode_fh() helper
  fs, exportfs: escape nil dereference if no s_export_op present
  fs, epoll: add procfs fdinfo helper
  fs, eventfd: add procfs fdinfo helper
  procfs: add ability to plug in auxiliary fdinfo providers
  tools/testing/selftests/kcmp/kcmp_test.c: print reason for failure in kcmp_test
  breakpoint selftests: print failure status instead of cause make error
  kcmp selftests: print fail status instead of cause make error
  kcmp selftests: make run_tests fix
  mem-hotplug selftests: print failure status instead of cause make error
  cpu-hotplug selftests: print failure status instead of cause make error
  mqueue selftests: print failure status instead of cause make error
  vm selftests: print failure status instead of cause make error
  ubifs: use prandom_bytes
  mtd: nandsim: use prandom_bytes
  ...
2012-12-17 20:58:12 -08:00
Andrew Morton 965c8e59cf lseek: the "whence" argument is called "whence"
But the kernel decided to call it "origin" instead.  Fix most of the
sites.

Acked-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-12-17 17:15:12 -08:00
Eric W. Biederman 499dcf2024 userns: Support fuse interacting with multiple user namespaces
Use kuid_t and kgid_t in struct fuse_conn and struct fuse_mount_data.

The connection between between a fuse filesystem and a fuse daemon is
established when a fuse filesystem is mounted and provided with a file
descriptor the fuse daemon created by opening /dev/fuse.

For now restrict the communication of uids and gids between the fuse
filesystem and the fuse daemon to the initial user namespace.  Enforce
this by verifying the file descriptor passed to the mount of fuse was
opened in the initial user namespace.  Ensuring the mount happens in
the initial user namespace is not necessary as mounts from non-initial
user namespaces are not yet allowed.

In fuse_req_init_context convert the currrent fsuid and fsgid into the
initial user namespace for the request that will be sent to the fuse
daemon.

In fuse_fill_attr convert the uid and gid passed from the fuse daemon
from the initial user namespace into kuids and kgids.

In iattr_to_fattr called from fuse_setattr convert kuids and kgids
into the uids and gids in the initial user namespace before passing
them to the fuse filesystem.

In fuse_change_attributes_common called from fuse_dentry_revalidate,
fuse_permission, fuse_geattr, and fuse_setattr, and fuse_iget convert
the uid and gid from the fuse daemon into a kuid and a kgid to store
on the fuse inode.

By default fuse mounts are restricted to task whose uid, suid, and
euid matches the fuse user_id and whose gid, sgid, and egid matches
the fuse group id.  Convert the user_id and group_id mount options
into kuids and kgids at mount time, and use uid_eq and gid_eq to
compare the in fuse_allow_task.

Cc: Miklos Szeredi <miklos@szeredi.hu>
Acked-by: Serge Hallyn <serge.hallyn@canonical.com>
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
2012-11-14 22:05:33 -08:00
Konstantin Khlebnikov 0b173bc4da mm: kill vma flag VM_CAN_NONLINEAR
Move actual pte filling for non-linear file mappings into the new special
vma operation: ->remap_pages().

Filesystems must implement this method to get non-linear mapping support,
if it uses filemap_fault() then generic_file_remap_pages() can be used.

Now device drivers can implement this method and obtain nonlinear vma support.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@openvz.org>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Carsten Otte <cotte@de.ibm.com>
Cc: Chris Metcalf <cmetcalf@tilera.com>	#arch/tile
Cc: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Eric Paris <eparis@redhat.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: James Morris <james.l.morris@oracle.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Kentaro Takeda <takedakn@nttdata.co.jp>
Cc: Matt Helsley <matthltc@us.ibm.com>
Cc: Nick Piggin <npiggin@kernel.dk>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Suresh Siddha <suresh.b.siddha@intel.com>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Venkatesh Pallipadi <venki@google.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2012-10-09 16:22:17 +09:00
Kirill A. Shutemov 8c0a853770 fs: push rcu_barrier() from deactivate_locked_super() to filesystems
There's no reason to call rcu_barrier() on every
deactivate_locked_super().  We only need to make sure that all delayed rcu
free inodes are flushed before we destroy related cache.

Removing rcu_barrier() from deactivate_locked_super() affects some fast
paths.  E.g.  on my machine exit_group() of a last process in IPC
namespace takes 0.07538s.  rcu_barrier() takes 0.05188s of that time.

Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-10-02 21:35:55 -04:00
Al Viro cb0942b812 make get_file() return its argument
simplifies a bunch of callers...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-09-26 21:10:25 -04:00
Miklos Szeredi c9e67d4837 fuse: fix retrieve length
In some cases fuse_retrieve() would return a short byte count if offset was
non-zero.  The data returned was correct, though.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Cc: stable@vger.kernel.org
2012-09-04 18:45:54 +02:00
Daniel Mack 381bf7cad9 fuse: mark variables uninitialized
gcc 4.6.3 complains about uninitialized variables in fs/fuse/control.c:

  CC      fs/fuse/control.o
fs/fuse/control.c: In function 'fuse_conn_congestion_threshold_write':
fs/fuse/control.c:165:29: warning: 'val' may be used uninitialized in this function [-Wuninitialized]
fs/fuse/control.c: In function 'fuse_conn_max_background_write':
fs/fuse/control.c:128:23: warning: 'val' may be used uninitialized in this function [-Wuninitialized]

fuse_conn_limit_write() will always return non-zero unless the &val
is modified, so the warning is misleading. Let the compiler know
about it by marking 'val' with 'uninitialized_var'.

Signed-off-by: Daniel Mack <zonque@gmail.com>
Cc: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-09-03 17:44:06 +02:00
Miklos Szeredi 8d39d801d6 cuse: kill connection on initialization error
Luca Risolia reported that a CUSE daemon will continue to run even if
initialization of the emulated device failes for some reason (e.g. the device
number is already registered by another driver).

This patch disconnects the fuse device on error, which will make the userspace
CUSE daemon exit, albeit without indication about what the problem was.

Reported-by: Luca Risolia <luca.risolia@studio.unibo.it>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-08-30 19:24:35 +02:00
Miklos Szeredi bbd9979797 cuse: fix fuse_conn_kill()
fuse_conn_kill() removed fc->entry, called fuse_ctl_remove_conn() and
fuse_bdi_destroy().  None of which is appropriate for cuse cleanup.

The fuse_ctl_remove_conn() decrements the nlink on the control filesystem, which
is totally bogus.  The others are harmless but unnecessary.

So move these out from fuse_conn_kill() to fuse_put_super() where they belong.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-08-30 19:24:34 +02:00
Linus Torvalds 20fb1936de Merge branch 'vfs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs
Pull vfs fixes from Miklos Szeredi.

This mainly fixes some confusion about whether the open 'mode' variable
passed around should contain the full file type (S_IFREG etc)
information or just the permission mode.  In particular, the lack of
proper file type information had confused fuse.

* 'vfs-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
  vfs: fix propagation of atomic_open create error on negative dentry
  fuse: check create mode in atomic open
  vfs: pass right create mode to may_o_create()
  vfs: atomic_open(): fix create mode usage
  vfs: canonicalize create mode in build_open_flags()
2012-08-18 10:02:17 -07:00
Linus Torvalds 2eac9eb8a2 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: verify all ioctl retry iov elements
  fuse: add missing INIT flag descriptions
  fuse: add missing INIT flags
  fuse: update attributes on aio_read
  fuse: invalidate inode mapping if mtime changes
  fuse: add FUSE_AUTO_INVAL_DATA init flag
2012-08-16 11:46:31 -07:00
Miklos Szeredi af109bca94 fuse: check create mode in atomic open
Verify that the VFS is passing us a complete create mode with the S_IFREG to
atomic open.

Reported-by: Steve <steveamigauk@yahoo.co.uk>
Reported-by: Richard W.M. Jones <rjones@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Richard W.M. Jones <rjones@redhat.com>
2012-08-15 13:01:24 +02:00
Zach Brown fb6ccff667 fuse: verify all ioctl retry iov elements
Commit 7572777eef attempted to verify that
the total iovec from the client doesn't overflow iov_length() but it
only checked the first element.  The iovec could still overflow by
starting with a small element.  The obvious fix is to check all the
elements.

The overflow case doesn't look dangerous to the kernel as the copy is
limited by the length after the overflow.  This fix restores the
intention of returning an error instead of successfully copying less
than the iovec represented.

I found this by code inspection.  I built it but don't have a test case.
I'm cc:ing stable because the initial commit did as well.

Signed-off-by: Zach Brown <zab@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: <stable@vger.kernel.org>         [2.6.37+]
2012-08-06 18:19:24 +02:00
Jan Kara 58ef6a75c3 fuse: Convert to new freezing mechanism
Convert check in fuse_file_aio_write() to using new freeze protection.

CC: fuse-devel@lists.sourceforge.net
CC: Miklos Szeredi <miklos@szeredi.hu>
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-31 09:45:50 +04:00
Miklos Szeredi 69fe05c90e fuse: add missing INIT flags
Add missing flags that userspace derived from the protocol version number.  This
makes the protocol more flexible.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-07-18 16:09:40 +02:00
Brian Foster a8894274a3 fuse: update attributes on aio_read
A fuse-based network filesystem might allow for the inode
and/or file data to change unexpectedly. A local client
that opens and repeatedly reads a file might never pick
up on such changes and indefinitely return stale data.

Always invoke fuse_update_attributes() in the read path
to cause an attr revalidation when the attributes expire.
This leads to a page cache invalidation if necessary and
ensures fuse issues new read requests to the fuse client.

The original logic (reval only on reads beyond EOF) is
preserved unless the client specifies FUSE_AUTO_INVAL_DATA
on init.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-07-18 16:09:40 +02:00
Brian Foster eed2179efe fuse: invalidate inode mapping if mtime changes
We currently invalidate the inode address space mapping
if the file size changes unexpectedly. In the case of a
fuse network filesystem, a portion of a file could be
overwritten remotely without changing the file size.
Compare the old mtime as well to detect this condition
and invalidate the mapping if the file has been updated.

The original logic (to ignore changes in mtime) is
preserved unless the client specifies FUSE_AUTO_INVAL_DATA
on init.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-07-18 16:09:40 +02:00
Brian Foster 72d0d248ca fuse: add FUSE_AUTO_INVAL_DATA init flag
FUSE_AUTO_INVAL_DATA is provided to enable updated/auto cache
invalidation logic.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-07-18 16:09:40 +02:00
Al Viro ebfc3b49a7 don't pass nameidata to ->create()
boolean "does it have to be exclusive?" flag is passed instead;
Local filesystem should just ignore it - the object is guaranteed
not to be there yet.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:47 +04:00
Al Viro 00cd8dd3bf stop passing nameidata to ->lookup()
Just the flags; only NFS cares even about that, but there are
legitimate uses for such argument.  And getting rid of that
completely would require splitting ->lookup() into a couple
of methods (at least), so let's leave that alone for now...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:32 +04:00
Al Viro 0b728e1911 stop passing nameidata * to ->d_revalidate()
Just the lookup flags.  Die, bastard, die...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:34:14 +04:00
Al Viro e45198a6ac make finish_no_open() return int
namely, 1 ;-)  That's what we want to return from ->atomic_open()
instances after finish_no_open().

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:45 +04:00
Al Viro 30d9049474 kill struct opendata
Just pass struct file *.  Methods are happier that way...
There's no need to return struct file * from finish_open() now,
so let it return int.  Next: saner prototypes for parts in
namei.c

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:39 +04:00
Al Viro d95852777b make ->atomic_open() return int
Change of calling conventions:
old		new
NULL		1
file		0
ERR_PTR(-ve)	-ve

Caller *knows* that struct file *; no need to return it.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:35 +04:00
Al Viro 47237687d7 ->atomic_open() prototype change - pass int * instead of bool *
... and let finish_open() report having opened the file via that sucker.
Next step: don't modify od->filp at all.

[AV: FILE_CREATE was already used by cifs; Miklos' fix folded]

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:31 +04:00
Miklos Szeredi c8ccbe032f fuse: implement i_op->atomic_open()
Add an ->atomic_open implementation which replaces the atomic open+create
operation implemented via ->create.  No functionality is changed.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:33:14 +04:00
Al Viro b3d9b7a3c7 vfs: switch i_dentry/d_alias to hlist
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-07-14 16:32:55 +04:00
Linus Torvalds f9ba7179ce Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: fix blksize calculation
  fuse: fix stat call on 32 bit platforms
  fuse: optimize fallocate on permanent failure
  fuse: add FALLOCATE operation
  fuse: Convert to kstrtoul_from_user
2012-06-05 10:11:11 -07:00
Josef Bacik c3b2da3148 fs: introduce inode operation ->update_time
Btrfs has to make sure we have space to allocate new blocks in order to modify
the inode, so updating time can fail.  We've gotten around this by having our
own file_update_time but this is kind of a pain, and Christoph has indicated he
would like to make xfs do something different with atime updates.  So introduce
->update_time, where we will deal with i_version an a/m/c time updates and
indicate which changes need to be made.  The normal version just does what it
has always done, updates the time and marks the inode dirty, and then
filesystems can choose to do something different.

I've gone through all of the users of file_update_time and made them check for
errors with the exception of the fault code since it's complicated and I wasn't
quite sure what to do there, also Jan is going to be pushing the file time
updates into page_mkwrite for those who have it so that should satisfy btrfs and
make it not a big deal to check the file_update_time() return code in the
generic fault path. Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
2012-06-01 12:07:25 -04:00
Al Viro b0b0382bb4 ->encode_fh() API change
pass inode + parent's inode or NULL instead of dentry + bool saying
whether we want the parent or not.

NOTE: that needs ceph fix folded in.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-05-29 23:28:33 -04:00
Linus Torvalds 90324cc1b1 avoid iput() from flusher thread
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Merge tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux

Pull writeback tree from Wu Fengguang:
 "Mainly from Jan Kara to avoid iput() in the flusher threads."

* tag 'writeback' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux:
  writeback: Avoid iput() from flusher thread
  vfs: Rename end_writeback() to clear_inode()
  vfs: Move waiting for inode writeback from end_writeback() to evict_inode()
  writeback: Refactor writeback_single_inode()
  writeback: Remove wb->list_lock from writeback_single_inode()
  writeback: Separate inode requeueing after writeback
  writeback: Move I_DIRTY_PAGES handling
  writeback: Move requeueing when I_SYNC set to writeback_sb_inodes()
  writeback: Move clearing of I_SYNC into inode_sync_complete()
  writeback: initialize global_dirty_limit
  fs: remove 8 bytes of padding from struct writeback_control on 64 bit builds
  mm: page-writeback.c: local functions should not be exposed globally
2012-05-28 09:54:45 -07:00
Miklos Szeredi 203627bbc9 fuse: fix blksize calculation
Don't use inode->i_blkbits which might be stale, instead calculate the blksize
information from the freshly obtained attributes.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-05-14 17:12:56 +02:00
Pavel Shilovsky 45c72cd73c fuse: fix stat call on 32 bit platforms
Now we store attr->ino at inode->i_ino, return attr->ino at the
first time and then return inode->i_ino if the attribute timeout
isn't expired. That's wrong on 32 bit platforms because attr->ino
is 64 bit and inode->i_ino is 32 bit in this case.

Fix this by saving 64 bit ino in fuse_inode structure and returning
it every time we call getattr. Also squash attr->ino into inode->i_ino
explicitly.

Signed-off-by: Pavel Shilovsky <piastry@etersoft.ru>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-05-14 17:06:42 +02:00
Jan Kara dbd5768f87 vfs: Rename end_writeback() to clear_inode()
After we moved inode_sync_wait() from end_writeback() it doesn't make sense
to call the function end_writeback() anymore. Rename it to clear_inode()
which well says what the function really does - set I_CLEAR flag.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Fengguang Wu <fengguang.wu@intel.com>
2012-05-06 13:43:41 +08:00
Miklos Szeredi 519c6040ce fuse: optimize fallocate on permanent failure
If userspace filesystem doesn't support fallocate, remember this and don't send
request next time.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-26 10:56:36 +02:00
Anatol Pomozov 05ba1f0823 fuse: add FALLOCATE operation
fallocate filesystem operation preallocates media space for the given file.
If fallocate returns success then any subsequent write to the given range
never fails with 'not enough space' error.

Signed-off-by: Anatol Pomozov <anatol.pomozov@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-25 12:25:05 +02:00
Peter Huewe e2690695ce fuse: Convert to kstrtoul_from_user
This patch replaces the code for getting an number from a
userspace buffer by a simple call to kstroul_from_user.
This makes it easier to read and less error prone.

Signed-off-by: Peter Huewe <peterhuewe@gmx.de>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-25 12:25:05 +02:00
Linus Torvalds dbfad21422 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
Pull fuse updates from Miklos Szeredi.

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: use flexible array in fuse.h
  fuse: allow nanosecond granularity
  fuse: O_DIRECT support for files
  fuse: fix nlink after unlink
2012-04-18 17:29:05 -07:00
Miklos Szeredi 0a2da9b2ef fuse: allow nanosecond granularity
Derrik Pates reports that an utimensat with a NULL argument results in the
current time being sent from the kernel with 1 second granularity.

Reported-by: Derrik Pates <demon@now.ai>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-04-11 11:45:06 +02:00
Linus Torvalds e2a0883e40 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
Pull vfs pile 1 from Al Viro:
 "This is _not_ all; in particular, Miklos' and Jan's stuff is not there
  yet."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (64 commits)
  ext4: initialization of ext4_li_mtx needs to be done earlier
  debugfs-related mode_t whack-a-mole
  hfsplus: add an ioctl to bless files
  hfsplus: change finder_info to u32
  hfsplus: initialise userflags
  qnx4: new helper - try_extent()
  qnx4: get rid of qnx4_bread/qnx4_getblk
  take removal of PF_FORKNOEXEC to flush_old_exec()
  trim includes in inode.c
  um: uml_dup_mmap() relies on ->mmap_sem being held, but activate_mm() doesn't hold it
  um: embed ->stub_pages[] into mmu_context
  gadgetfs: list_for_each_safe() misuse
  ocfs2: fix leaks on failure exits in module_init
  ecryptfs: make register_filesystem() the last potential failure exit
  ntfs: forgets to unregister sysctls on register_filesystem() failure
  logfs: missing cleanup on register_filesystem() failure
  jfs: mising cleanup on register_filesystem() failure
  make configfs_pin_fs() return root dentry on success
  configfs: configfs_create_dir() has parent dentry in dentry->d_parent
  configfs: sanitize configfs_create()
  ...
2012-03-21 13:36:41 -07:00
Al Viro 48fde701af switch open-coded instances of d_make_root() to new helper
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-03-20 21:29:35 -04:00
Cong Wang 2408f6ef6b fuse: remove the second argument of k[un]map_atomic()
Signed-off-by: Cong Wang <amwang@redhat.com>
2012-03-20 21:48:22 +08:00
Anand Avati 4273b793ec fuse: O_DIRECT support for files
Implement ->direct_IO() method in aops. The ->direct_IO() method combines
the existing fuse_direct_read/fuse_direct_write methods to implement
O_DIRECT functionality.

Reaching ->direct_IO() in the read path via generic_file_aio_read ensures
proper synchronization with page cache with its existing framework.

Reaching ->direct_IO() in the write path via fuse_file_aio_write is made
to come via generic_file_direct_write() which makes it play nice with
the page cache w.r.t other mmap pages etc.

On files marked 'direct_io' by the filesystem server, IO always follows
the fuse_direct_read/write path. There is no effect of fcntl(O_DIRECT)
and it always succeeds.

On files not marked with 'direct_io' by the filesystem server, the IO
path depends on O_DIRECT flag by the application. This can be passed
at the time of open() as well as via fcntl().

Note that asynchronous O_DIRECT iocb jobs are completed synchronously
always (this has been the case with FUSE even before this patch)

Signed-off-by: Anand Avati <avati@redhat.com>
Reviewed-by: Jeff Moyer <jmoyer@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-03-05 15:48:11 +01:00
Miklos Szeredi ac45d61357 fuse: fix nlink after unlink
Anand Avati reports that the following sequence of system calls fail on a fuse
filesystem:


 	create("filename") => 0
 	link("filename", "linkname") => 0
 	unlink("filename") => 0
 	link("linkname", "filename") => -ENOENT ### BUG ###

vfs_link() fails with ENOENT if i_nlink is zero, this is done to prevent
resurrecting already deleted files.

Fuse clears i_nlink on unlink even if there are other links pointing to the
file.

Reported-by: Anand Avati <avati@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-03-05 15:48:11 +01:00
Linus Torvalds 6733e54b66 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  FUSE: Notifying the kernel of deletion.
  fuse: support ioctl on directories
  fuse: Use kcalloc instead of kzalloc to allocate array
  fuse: llseek optimize SEEK_CUR and SEEK_SET
2012-01-12 12:39:21 -08:00
Al Viro 34c80b1d93 vfs: switch ->show_options() to struct dentry *
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-06 23:19:54 -05:00
Al Viro 541af6a074 fuse: propagate umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:55:07 -05:00
Al Viro 1a67aafb5f switch ->mknod() to umode_t
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:54 -05:00
Al Viro 4acdaf27eb switch ->create() to umode_t
vfs_create() ignores everything outside of 16bit subset of its
mode argument; switching it to umode_t is obviously equivalent
and it's the only caller of the method

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Al Viro 18bb1db3e7 switch vfs_mkdir() and ->mkdir() to umode_t
vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:54:53 -05:00
Al Viro 6b520e0565 vfs: fix the stupidity with i_dentry in inode destructors
Seeing that just about every destructor got that INIT_LIST_HEAD() copied into
it, there is no point whatsoever keeping this INIT_LIST_HEAD in inode_init_once();
the cost of taking it into inode_init_always() will be negligible for pipes
and sockets and negative for everything else.  Not to mention the removal of
boilerplate code from ->destroy_inode() instances...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2012-01-03 22:52:40 -05:00
Linus Torvalds 30aaca4582 Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: llseek fix race
  fuse: fix llseek bug
  fuse: fix fuse_retrieve
2011-12-14 18:23:35 -08:00
Al Viro 988f032567 fuse: register_filesystem() called too early
same story as with ubifs

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-12-13 12:35:14 -05:00
John Muir 451d0f5999 FUSE: Notifying the kernel of deletion.
Allows a FUSE file-system to tell the kernel when a file or directory is
deleted. If the specified dentry has the specified inode number, the kernel will
unhash it.

The current 'fuse_notify_inval_entry' does not cause the kernel to clean up
directories that are in use properly, and as a result the users of those
directories see incorrect semantics from the file-system. The error condition
seen when 'fuse_notify_inval_entry' is used to notify of a deleted directory is
avoided when 'fuse_notify_delete' is used instead.

The following scenario demonstrates the difference:
1. User A chdirs into 'testdir' and starts reading 'testfile'.
2. User B rm -rf 'testdir'.
3. User B creates 'testdir'.
4. User C chdirs into 'testdir'.

If you run the above within the same machine on any file-system (including fuse
file-systems), there is no problem: user C is able to chdir into the new
testdir. The old testdir is removed from the dentry tree, but still open by user
A.

If operations 2 and 3 are performed via the network such that the fuse
file-system uses one of the notify functions to tell the kernel that the nodes
are gone, then the following error occurs for user C while user A holds the
original directory open:

muirj@empacher:~> ls /test/testdir
ls: cannot access /test/testdir: No such file or directory

The issue here is that the kernel still has a dentry for testdir, and so it is
requesting the attributes for the old directory, while the file-system is
responding that the directory no longer exists.

If on the other hand, if the file-system can notify the kernel that the
directory is deleted using the new 'fuse_notify_delete' function, then the above
ls will find the new directory as expected.

Signed-off-by: John Muir <john@jmuir.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:58:49 +01:00
Miklos Szeredi b18da0c56e fuse: support ioctl on directories
Multiplexing filesystems may want to support ioctls on the underlying
files and directores (e.g. FS_IOC_{GET,SET}FLAGS).

Ioctl support on directories was missing so add it now.

Reported-by: Antonio SJ Musumeci <bile@landofbile.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:58:49 +01:00
Thomas Meyer c411cc88d8 fuse: Use kcalloc instead of kzalloc to allocate array
The advantage of kcalloc is, that will prevent integer overflows which could
result from the multiplication of number of elements and size and it is also
a bit nicer to read.

The semantic patch that makes this change is available
in https://lkml.org/lkml/2011/11/25/107

Signed-off-by: Thomas Meyer <thomas@m3y3r.de>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:58:49 +01:00
Miklos Szeredi c07c3d1934 fuse: llseek optimize SEEK_CUR and SEEK_SET
Use generic_file_llseek() instead of open coding the seek function.

i_mutex protection is only necessary for SEEK_END (and SEEK_HOLE, SEEK_DATA), so
move SEEK_CUR and SEEK_SET out from under i_mutex.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:58:48 +01:00
Miklos Szeredi 73104b6e37 fuse: llseek fix race
Fix race between lseek(fd, 0, SEEK_CUR) and read/write.  This was fixed in
generic code by commit 5b6f1eb97d (vfs: lseek(fd, 0, SEEK_CUR) race condition).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-12-13 11:40:59 +01:00
Roel Kluin b48c6af208 fuse: fix llseek bug
The test in fuse_file_llseek() "not SEEK_CUR or not SEEK_SET" always evaluates
to true.

This was introduced in 3.1 by commit 06222e49 (fs: handle SEEK_HOLE/SEEK_DATA
properly in all fs's that define their own llseek) and changed the behavior of
SEEK_CUR and SEEK_SET to always retrieve the file attributes.  This is a
performance regression.

Fix the test so that it makes sense.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@vger.kernel.org
CC: Josef Bacik <josef@redhat.com>
CC: Al Viro <viro@zeniv.linux.org.uk>
2011-12-13 10:37:00 +01:00
Miklos Szeredi 48706d0a91 fuse: fix fuse_retrieve
Fix two bugs in fuse_retrieve():

 - retrieving more than one page would yield repeated instances of the
   first page

 - if more than FUSE_MAX_PAGES_PER_REQ pages were requested than the
   request page array would overflow

fuse_retrieve() was added in 2.6.36 and these bugs had been there since the
beginning.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@vger.kernel.org
2011-12-13 10:36:59 +01:00
Linus Torvalds 32aaeffbd4 Merge branch 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux
* 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits)
  Revert "tracing: Include module.h in define_trace.h"
  irq: don't put module.h into irq.h for tracking irqgen modules.
  bluetooth: macroize two small inlines to avoid module.h
  ip_vs.h: fix implicit use of module_get/module_put from module.h
  nf_conntrack.h: fix up fallout from implicit moduleparam.h presence
  include: replace linux/module.h with "struct module" wherever possible
  include: convert various register fcns to macros to avoid include chaining
  crypto.h: remove unused crypto_tfm_alg_modname() inline
  uwb.h: fix implicit use of asm/page.h for PAGE_SIZE
  pm_runtime.h: explicitly requires notifier.h
  linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h
  miscdevice.h: fix up implicit use of lists and types
  stop_machine.h: fix implicit use of smp.h for smp_processor_id
  of: fix implicit use of errno.h in include/linux/of.h
  of_platform.h: delete needless include <linux/module.h>
  acpi: remove module.h include from platform/aclinux.h
  miscdevice.h: delete unnecessary inclusion of module.h
  device_cgroup.h: delete needless include <linux/module.h>
  net: sch_generic remove redundant use of <linux/module.h>
  net: inet_timewait_sock doesnt need <linux/module.h>
  ...

Fix up trivial conflicts (other header files, and  removal of the ab3550 mfd driver) in
 - drivers/media/dvb/frontends/dibx000_common.c
 - drivers/media/video/{mt9m111.c,ov6650.c}
 - drivers/mfd/ab3550-core.c
 - include/linux/dmaengine.h
2011-11-06 19:44:47 -08:00
Miklos Szeredi bfe8684869 filesystems: add set_nlink()
Replace remaining direct i_nlink updates with a new set_nlink()
updater function.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Toshiyuki Okajima <toshi.okajima@jp.fujitsu.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2011-11-02 12:53:43 +01:00
Paul Gortmaker 143cb494cb fs: add module.h to files that were implicitly using it
Some files were using the complete module.h infrastructure without
actually including the header at all.  Fix them up in advance so
once the implicit presence is removed, we won't get failures like this:

  CC [M]  fs/nfsd/nfssvc.o
fs/nfsd/nfssvc.c: In function 'nfsd_create_serv':
fs/nfsd/nfssvc.c:335: error: 'THIS_MODULE' undeclared (first use in this function)
fs/nfsd/nfssvc.c:335: error: (Each undeclared identifier is reported only once
fs/nfsd/nfssvc.c:335: error: for each function it appears in.)
fs/nfsd/nfssvc.c: In function 'nfsd':
fs/nfsd/nfssvc.c:555: error: implicit declaration of function 'module_put_and_exit'
make[3]: *** [fs/nfsd/nfssvc.o] Error 1

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-10-31 19:30:31 -04:00
Miklos Szeredi 5dfcc87fd7 fuse: fix memory leak
kmemleak is reporting that 32 bytes are being leaked by FUSE:

  unreferenced object 0xe373b270 (size 32):
  comm "fusermount", pid 1207, jiffies 4294707026 (age 2675.187s)
  hex dump (first 32 bytes):
    01 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<b05517d7>] kmemleak_alloc+0x27/0x50
    [<b0196435>] kmem_cache_alloc+0xc5/0x180
    [<b02455be>] fuse_alloc_forget+0x1e/0x20
    [<b0245670>] fuse_alloc_inode+0xb0/0xd0
    [<b01b1a8c>] alloc_inode+0x1c/0x80
    [<b01b290f>] iget5_locked+0x8f/0x1a0
    [<b0246022>] fuse_iget+0x72/0x1a0
    [<b02461da>] fuse_get_root_inode+0x8a/0x90
    [<b02465cf>] fuse_fill_super+0x3ef/0x590
    [<b019e56f>] mount_nodev+0x3f/0x90
    [<b0244e95>] fuse_mount+0x15/0x20
    [<b019d1bc>] mount_fs+0x1c/0xc0
    [<b01b5811>] vfs_kern_mount+0x41/0x90
    [<b01b5af9>] do_kern_mount+0x39/0xd0
    [<b01b7585>] do_mount+0x2e5/0x660
    [<b01b7966>] sys_mount+0x66/0xa0

This leak report is consistent and happens once per boot on
3.1.0-rc5-dirty.

This happens if a FORGET request is queued after the fuse device was
released.

Reported-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Sitsofe Wheeler <sitsofe@yahoo.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-12 11:47:10 -07:00
Miklos Szeredi 24114504c4 fuse: fix flock breakage
Commit 37fb3a30b4 ("fuse: fix flock") added in 3.1-rc4 caused flock() to
fail with ENOSYS with the kernel ABI version 7.16 or earlier.

Fix by falling back to testing FUSE_POSIX_LOCKS for ABI versions 7.16
and earlier.

Reported-by: Martin Ziegler <ziegler@email.mathematik.uni-freiburg.de>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Tested-by: Martin Ziegler <ziegler@email.mathematik.uni-freiburg.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2011-09-12 11:47:10 -07:00
Linus Torvalds 051732bcbe Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  fuse: check size of FUSE_NOTIFY_INVAL_ENTRY message
  fuse: mark pages accessed when written to
  fuse: delete dead .write_begin and .write_end aops
  fuse: fix flock
  fuse: fix non-ANSI void function notation
2011-08-24 09:14:42 -07:00
Miklos Szeredi c2183d1e9b fuse: check size of FUSE_NOTIFY_INVAL_ENTRY message
FUSE_NOTIFY_INVAL_ENTRY didn't check the length of the write so the
message processing could overrun and result in a "kernel BUG at
fs/fuse/dev.c:629!"

Reported-by: Han-Wen Nienhuys <hanwenn@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
2011-08-24 10:20:17 +02:00
Johannes Weiner 478e0841b3 fuse: mark pages accessed when written to
As fuse does not use the page cache library functions when userspace
writes to a file, it did not benefit from 'c8236db mm: mark page
accessed before we write_end()' that made sure pages are properly
marked accessed when written to.

Signed-off-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-08-08 16:08:08 +02:00
Johannes Weiner b40cdd56df fuse: delete dead .write_begin and .write_end aops
Ever since 'ea9b990 fuse: implement perform_write', the .write_begin
and .write_end aops have been dead code.

Their task - acquiring a page from the page cache, sending out a write
request and releasing the page again - is now done batch-wise to
maximize the number of pages send per userspace request.

Signed-off-by: Johannes Weiner <jweiner@redhat.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-08-08 16:08:08 +02:00
Miklos Szeredi 37fb3a30b4 fuse: fix flock
Commit a9ff4f87 "fuse: support BSD locking semantics" overlooked a
number of issues with supporing flock locks over existing POSIX
locking infrastructure:

  - it's not backward compatible, passing flock(2) calls to userspace
    unconditionally (if userspace sets FUSE_POSIX_LOCKS)

  - it doesn't cater for the fact that flock locks are automatically
    unlocked on file release

  - it doesn't take into account the fact that flock exclusive locks
    (write locks) don't need an fd opened for write.

The last one invalidates the original premise of the patch that flock
locks can be emulated with POSIX locks.

This patch fixes the first two issues.  The last one needs to be fixed
in userspace if the filesystem assumed that a write lock will happen
only on a file operned for write (as in the case of the current fuse
library).

Reported-by: Sebastian Pipping <webmaster@hartwork.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-08-08 16:08:08 +02:00
Linus Torvalds 2dad3206db Merge branch 'for-3.1' of git://linux-nfs.org/~bfields/linux
* 'for-3.1' of git://linux-nfs.org/~bfields/linux:
  nfsd: don't break lease on CLAIM_DELEGATE_CUR
  locks: rename lock-manager ops
  nfsd4: update nfsv4.1 implementation notes
  nfsd: turn on reply cache for NFSv4
  nfsd4: call nfsd4_release_compoundargs from pc_release
  nfsd41: Deny new lock before RECLAIM_COMPLETE done
  fs: locks: remove init_once
  nfsd41: check the size of request
  nfsd41: error out when client sets maxreq_sz or maxresp_sz too small
  nfsd4: fix file leak on open_downgrade
  nfsd4: remember to put RW access on stateid destruction
  NFSD: Added TEST_STATEID operation
  NFSD: added FREE_STATEID operation
  svcrpc: fix list-corrupting race on nfsd shutdown
  rpc: allow autoloading of gss mechanisms
  svcauth_unix.c: quiet sparse noise
  svcsock.c: include sunrpc.h to quiet sparse noise
  nfsd: Remove deprecated nfsctl system call and related code.
  NFSD: allow OP_DESTROY_CLIENTID to be only op in COMPOUND

Fix up trivial conflicts in Documentation/feature-removal-schedule.txt
2011-07-25 22:49:19 -07:00
Josef Bacik 02c24a8218 fs: push i_mutex and filemap_write_and_wait down into ->fsync() handlers
Btrfs needs to be able to control how filemap_write_and_wait_range() is called
in fsync to make it less of a painful operation, so push down taking i_mutex and
the calling of filemap_write_and_wait() down into the ->fsync() handlers.  Some
file systems can drop taking the i_mutex altogether it seems, like ext3 and
ocfs2.  For correctness sake I just pushed everything down in all cases to make
sure that we keep the current behavior the same for everybody, and then each
individual fs maintainer can make up their mind about what to do from there.
Thanks,

Acked-by: Jan Kara <jack@suse.cz>
Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 20:47:59 -04:00
Josef Bacik 06222e491e fs: handle SEEK_HOLE/SEEK_DATA properly in all fs's that define their own llseek
This converts everybody to handle SEEK_HOLE/SEEK_DATA properly.  In some cases
we just return -EINVAL, in others we do the normal generic thing, and in others
we're simply making sure that the properly due-dilligence is done.  For example
in NFS/CIFS we need to make sure the file size is update properly for the
SEEK_HOLE and SEEK_DATA case, but since it calls the generic llseek stuff itself
that is all we have to do.  Thanks,

Signed-off-by: Josef Bacik <josef@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 20:47:58 -04:00
J. Bruce Fields 8fb47a4fbf locks: rename lock-manager ops
Both the filesystem and the lock manager can associate operations with a
lock.  Confusingly, one of them (fl_release_private) actually has the
same name in both operation structures.

It would save some confusion to give the lock-manager ops different
names.

Signed-off-by: J. Bruce Fields <bfields@redhat.com>
2011-07-20 20:23:19 -04:00
Al Viro dd7dd556e4 no need to check for LOOKUP_OPEN in ->create() instances
... it will be set in nd->flag for all cases with non-NULL nd
(i.e. when called from do_last()).

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:56 -04:00
Al Viro 8a5e929dd2 don't transliterate lower bits of ->intent.open.flags to FMODE_...
->create() instances are much happier that way...

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:52 -04:00
Al Viro 10556cb21a ->permission() sanitizing: don't pass flags to ->permission()
not used by the instances anymore.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:24 -04:00
Al Viro 2830ba7f34 ->permission() sanitizing: don't pass flags to generic_permission()
redundant; all callers get it duplicated in mask & MAY_NOT_BLOCK and none of
them removes that bit.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:22 -04:00
Al Viro 178ea73521 kill check_acl callback of generic_permission()
its value depends only on inode and does not change; we might as
well store it in ->i_op->check_acl and be done with that.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-07-20 01:43:16 -04:00
Al Viro 9e1f1de02c more conservative S_NOSEC handling
Caching "we have already removed suid/caps" was overenthusiastic as merged.
On network filesystems we might have had suid/caps set on another client,
silently picked by this client on revalidate, all of that *without* clearing
the S_NOSEC flag.

AFAICS, the only reasonably sane way to deal with that is
	* new superblock flag; unless set, S_NOSEC is not going to be set.
	* local block filesystems set it in their ->mount() (more accurately,
mount_bdev() does, so does btrfs ->mount(), users of mount_bdev() other than
local block ones clear it)
	* if any network filesystem (or a cluster one) wants to use S_NOSEC,
it'll need to set MS_NOSEC in sb->s_flags *AND* take care to clear S_NOSEC when
inode attribute changes are picked from other clients.

It's not an earth-shattering hole (anybody that can set suid on another client
will almost certainly be able to write to the file before doing that anyway),
but it's a bug that needs fixing.

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-06-03 18:24:58 -04:00
Randy Dunlap a2daff6803 fuse: fix non-ANSI void function notation
Fix void function parameter list sparse warning:

fs/fuse/inode.c:74:44: warning: non-ANSI function declaration of function 'fuse_alloc_forget'

Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-06-01 16:09:32 +02:00
Sage Weil 526e7ce552 fuse: remove unnecessary dentry_unhash on rmdir, dir rename
Fuse has no problems with references to unlinked directories.

CC: Miklos Szeredi <miklos@szeredi.hu>
CC: fuse-devel@lists.sourceforge.net
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-28 01:02:53 -04:00
Linus Torvalds 32e51f141f Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (25 commits)
  cifs: remove unnecessary dentry_unhash on rmdir/rename_dir
  ocfs2: remove unnecessary dentry_unhash on rmdir/rename_dir
  exofs: remove unnecessary dentry_unhash on rmdir/rename_dir
  nfs: remove unnecessary dentry_unhash on rmdir/rename_dir
  ext2: remove unnecessary dentry_unhash on rmdir/rename_dir
  ext3: remove unnecessary dentry_unhash on rmdir/rename_dir
  ext4: remove unnecessary dentry_unhash on rmdir/rename_dir
  btrfs: remove unnecessary dentry_unhash in rmdir/rename_dir
  ceph: remove unnecessary dentry_unhash calls
  vfs: clean up vfs_rename_other
  vfs: clean up vfs_rename_dir
  vfs: clean up vfs_rmdir
  vfs: fix vfs_rename_dir for FS_RENAME_DOES_D_MOVE filesystems
  libfs: drop unneeded dentry_unhash
  vfs: update dentry_unhash() comment
  vfs: push dentry_unhash on rename_dir into file systems
  vfs: push dentry_unhash on rmdir into file systems
  vfs: remove dget() from dentry_unhash()
  vfs: dentry_unhash immediately prior to rmdir
  vfs: Block mmapped writes while the fs is frozen
  ...
2011-05-26 09:52:14 -07:00
Sage Weil e4eaac06bc vfs: push dentry_unhash on rename_dir into file systems
Only a few file systems need this.  Start by pushing it down into each
rename method (except gfs2 and xfs) so that it can be dealt with on a
per-fs basis.

Acked-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2011-05-26 07:26:48 -04:00