Commit Graph

268 Commits

Author SHA1 Message Date
Jens Axboe d993831fa7 writeback: add name to backing_dev_info
This enables us to track who does what and print info. Its main use
is catching dirty inodes on the default_backing_dev_info, so we can
fix that up.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-09-11 09:20:26 +02:00
Linus Torvalds 81e4e1ba7e Revert "fuse: Fix build error" as unnecessary
This reverts commit 097041e576.

Trond had a better fix, which is the parent of this one ("Fix compile
error due to congestion_wait() changes")

Requested-by: Trond Myklebust <Trond.Myklebust@netapp.com>
Acked-by: Larry Finger <Larry.Finger@lwfinger.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-11 11:22:34 -07:00
Larry Finger 097041e576 fuse: Fix build error
When building v2.6.31-rc2-344-g69ca06c, the following build errors are
found due to missing includes:

 CC [M]  fs/fuse/dev.o
fs/fuse/dev.c: In function ‘request_end’:
fs/fuse/dev.c:289: error: ‘BLK_RW_SYNC’ undeclared (first use in this function)
...
fs/nfs/write.c: In function ‘nfs_set_page_writeback’:
fs/nfs/write.c:207: error: ‘BLK_RW_ASYNC’ undeclared (first use in this function)

Signed-off-by: Larry Finger@lwfinger.net>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-07-10 19:09:46 -07:00
Jens Axboe 8aa7e847d8 Fix congestion_wait() sync/async vs read/write confusion
Commit 1faa16d228 accidentally broke
the bdi congestion wait queue logic, causing us to wait on congestion
for WRITE (== 1) when we really wanted BLK_RW_ASYNC (== 0) instead.

Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
2009-07-10 20:31:53 +02:00
John Muir 3b463ae0c6 fuse: invalidation reverse calls
Add notification messages that allow the filesystem to invalidate VFS
caches.

Two notifications are added:

 1) inode invalidation

   - invalidate cached attributes
   - invalidate a range of pages in the page cache (this is optional)

 2) dentry invalidation

   - try to invalidate a subtree in the dentry cache

Care must be taken while accessing the 'struct super_block' for the
mount, as it can go away while an invalidation is in progress.  To
prevent this, introduce a rw-semaphore, that is taken for read during
the invalidation and taken for write in the ->kill_sb callback.

Cc: Csaba Henk <csaba@gluster.com>
Cc: Anand Avati <avati@zresearch.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-06-30 20:12:24 +02:00
Miklos Szeredi e0a43ddcc0 fuse: allow umask processing in userspace
This patch lets filesystems handle masking the file mode on creation.
This is needed if filesystem is using ACLs.

 - The CREATE, MKDIR and MKNOD requests are extended with a "umask"
   parameter.

 - A new FUSE_DONT_MASK flag is added to the INIT request/reply.  With
   this the filesystem may request that the create mode is not masked.

CC: Jean-Pierre André <jean-pierre.andre@wanadoo.fr>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-06-30 20:12:23 +02:00
Miklos Szeredi 201fa69a28 fuse: fix bad return value in fuse_file_poll()
Fix fuse_file_poll() which returned a -errno value instead of a poll
mask.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
2009-06-30 20:06:24 +02:00
Csaba Henk b4c458b3a2 fuse: fix return value of fuse_dev_write()
On 64 bit systems -- where sizeof(ssize_t) > sizeof(int) -- the following test
exposes a bug due to a non-careful return of an int or unsigned value:

implement a FUSE filesystem which sends an unsolicited notification to
the kernel with invalid opcode. The respective write to /dev/fuse
will return (1 << 32) - EINVAL with errno == 0 instead of -1 with
errno == EINVAL.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
2009-06-30 20:06:23 +02:00
Al Viro 66c6af2e8b fuse doesn't need BKL in ->umount_begin()
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-06-17 00:36:36 -04:00
Linus Torvalds c34752bc8b Merge branch 'cuse' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse
* 'cuse' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse:
  CUSE: implement CUSE - Character device in Userspace
  fuse: export symbols to be used by CUSE
  fuse: update fuse_conn_init() and separate out fuse_conn_kill()
  fuse: don't use inode in fuse_file_poll
  fuse: don't use inode in fuse_do_ioctl() helper
  fuse: don't use inode in fuse_sync_release()
  fuse: create fuse_do_open() helper for CUSE
  fuse: clean up args in fuse_finish_open() and fuse_release_fill()
  fuse: don't use inode in helpers called by fuse_direct_io()
  fuse: add members to struct fuse_file
  fuse: prepare fuse_direct_io() for CUSE
  fuse: clean up fuse_write_fill()
  fuse: use struct path in release structure
  fuse: misc cleanups
2009-06-12 09:31:20 -07:00
Tejun Heo 151060ac13 CUSE: implement CUSE - Character device in Userspace
CUSE enables implementing character devices in userspace.  With recent
additions of ioctl and poll support, FUSE already has most of what's
necessary to implement character devices.  All CUSE has to do is
bonding all those components - FUSE, chardev and the driver model -
nicely.

When client opens /dev/cuse, kernel starts conversation with
CUSE_INIT.  The client tells CUSE which device it wants to create.  As
the previous patch made fuse_file usable without associated
fuse_inode, CUSE doesn't create super block or inodes.  It attaches
fuse_file to cdev file->private_data during open and set ff->fi to
NULL.  The rest of the operation is almost identical to FUSE direct IO
case.

Each CUSE device has a corresponding directory /sys/class/cuse/DEVNAME
(which is symlink to /sys/devices/virtual/class/DEVNAME if
SYSFS_DEPRECATED is turned off) which hosts "waiting" and "abort"
among other things.  Those two files have the same meaning as the FUSE
control files.

The only notable lacking feature compared to in-kernel implementation
is mmap support.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-06-09 11:24:11 +02:00
Linus Torvalds a6aeeebf51 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: destroy bdi on error
2009-05-13 16:32:57 -07:00
Alessio Igor Bogani 67e55205ec vfs: umount_begin BKL pushdown
Push BKL down into ->umount_begin()

Signed-off-by: Alessio Igor Bogani <abogani@texware.it>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-05-09 10:49:38 -04:00
Tejun Heo 08cbf542bf fuse: export symbols to be used by CUSE
Export the following symbols for CUSE.

fuse_conn_put()
fuse_conn_get()
fuse_conn_kill()
fuse_send_init()
fuse_do_open()
fuse_sync_release()
fuse_direct_io()
fuse_do_ioctl()
fuse_file_poll()
fuse_request_alloc()
fuse_get_req()
fuse_put_request()
fuse_request_send()
fuse_abort_conn()
fuse_dev_release()
fuse_dev_operations

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:42 +02:00
Tejun Heo a325f9b922 fuse: update fuse_conn_init() and separate out fuse_conn_kill()
Update fuse_conn_init() such that it doesn't take @sb and move bdi
registration into a separate function.  Also separate out
fuse_conn_kill() from fuse_put_super().

These will be used to implement cuse.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:41 +02:00
Miklos Szeredi 797759aaf3 fuse: don't use inode in fuse_file_poll
Use ff->fc and ff->nodeid instead of file->f_dentry->d_inode in the
fuse_file_poll() implementation.

This prepares this function for use by CUSE, where the inode is not
owned by a fuse filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:41 +02:00
Miklos Szeredi d36f248710 fuse: don't use inode in fuse_do_ioctl() helper
Create a helper for sending an IOCTL request that doesn't use a struct
inode.

This prepares this function for use by CUSE, where the inode is not
owned by a fuse filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
Miklos Szeredi 8b0797a498 fuse: don't use inode in fuse_sync_release()
Make fuse_sync_release() a generic helper function that doesn't need a
struct inode pointer.  This makes it suitable for use by CUSE.

Change return value of fuse_release_common() from int to void.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:39 +02:00
Miklos Szeredi 91fe96b403 fuse: create fuse_do_open() helper for CUSE
Create a helper for sending an OPEN request that doesn't need a struct
inode pointer.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
Miklos Szeredi c7b7143c63 fuse: clean up args in fuse_finish_open() and fuse_release_fill()
Move setting ff->fh, ff->nodeid and file->private_data outside
fuse_finish_open().  Add ->open_flags member to struct fuse_file.

This simplifies the argument passing to fuse_finish_open() and
fuse_release_fill(), and paves the way for creating an open helper
that doesn't need an inode pointer.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
Miklos Szeredi 2106cb1893 fuse: don't use inode in helpers called by fuse_direct_io()
Use ff->fc and ff->nodeid instead of passing down the inode.

This prepares this function for use by CUSE, where the inode is not
owned by a fuse filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:37 +02:00
Miklos Szeredi da5e471457 fuse: add members to struct fuse_file
Add new members ->fc and ->nodeid to struct fuse_file.  This will aid
in converting functions for use by CUSE, where the inode is not owned
by a fuse filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
Miklos Szeredi d09cb9d7f6 fuse: prepare fuse_direct_io() for CUSE
Move code operating on the inode out from fuse_direct_io().

This prepares this function for use by CUSE, where the inode is not
owned by a fuse filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
Miklos Szeredi 2d698b0703 fuse: clean up fuse_write_fill()
Move out code from fuse_write_fill() which is not common to all
callers.  Remove two function arguments which become unnecessary.

Also remove unnecessary memset(), the request is already initialized
to zero.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
Miklos Szeredi b0be46ebf7 fuse: use struct path in release structure
Use struct path instead of separate dentry and vfsmount in
req->misc.release.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:36 +02:00
Miklos Szeredi fd9db72977 fuse: destroy bdi on error
Destroy bdi on error in fuse_fill_super().

This was an omission from commit 26c3679101
"fuse: destroy bdi on umount", which moved the bdi_destroy() call from
fuse_conn_put() to fuse_put_super().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
2009-04-28 16:56:35 +02:00
Tejun Heo 6b2db28a7a fuse: misc cleanups
* fuse_file_alloc() was structured in weird way.  The success path was
  split between else block and code following the block.  Restructure
  the code such that it's easier to read and modify.

* Unindent success path of fuse_release_common() to ease future
  changes.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-28 16:56:35 +02:00
Miklos Szeredi 3121bfe763 fuse: fix "direct_io" private mmap
MAP_PRIVATE mmap could return stale data from the cache for
"direct_io" files.  Fix this by flushing the cache on mmap. 

Found with a slightly modified fsx-linux.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-09 17:37:53 +02:00
Miklos Szeredi ce60a2f157 fuse: fix argument type in fuse_get_user_pages()
Fix the following warning:

fs/fuse/file.c: In function 'fuse_direct_io':
fs/fuse/file.c:1002: warning: passing argument 3 of 'fuse_get_user_pages' from incompatible pointer type

This was introduced by commit f4975c67 "fuse: allow kernel to access
"direct_io" files".

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-09 17:37:52 +02:00
Miklos Szeredi fc280c9692 fuse: allow private mappings of "direct_io" files
Allow MAP_PRIVATE mmaps of "direct_io" files.  This is necessary for
execute support.

MAP_SHARED mappings require some sort of coherency between the
underlying file and the mapping.  With "direct_io" it is difficult to
provide this, so for the moment just disallow shared (read-write and
read-only) mappings altogether.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:35 +02:00
Miklos Szeredi f4975c67dd fuse: allow kernel to access "direct_io" files
Allow the kernel read and write on "direct_io" files.  This is
necessary for nfs export and execute support.

The implementation is simple: if an access from the kernel is
detected, don't perform get_user_pages(), just use the kernel address
provided by the requester to copy from/to the userspace filesystem.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-04-02 14:25:34 +02:00
Nick Piggin c2ec175c39 mm: page_mkwrite change prototype to match fault
Change the page_mkwrite prototype to take a struct vm_fault, and return
VM_FAULT_xxx flags.  There should be no functional change.

This makes it possible to return much more detailed error information to
the VM (and also can provide more information eg.  virtual_address to the
driver, which might be important in some special cases).

This is required for a subsequent fix.  And will also make it easier to
merge page_mkwrite() with fault() in future.

Signed-off-by: Nick Piggin <npiggin@suse.de>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Trond Myklebust <trond.myklebust@fys.uio.no>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Steven Whitehouse <swhiteho@redhat.com>
Cc: Mark Fasheh <mfasheh@suse.com>
Cc: Joel Becker <joel.becker@oracle.com>
Cc: Artem Bityutskiy <dedekind@infradead.org>
Cc: Felix Blyakher <felixb@sgi.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-04-01 08:59:14 -07:00
Dan Carpenter 5291658d87 fuse: fix fuse_file_lseek returning with lock held
This bug was found with smatch (http://repo.or.cz/w/smatch.git/).  If
we return directly the inode->i_mutex lock doesn't get released.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
2009-03-30 17:26:24 +02:00
Al Viro 4269590a72 constify dentry_operations: FUSE
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2009-03-27 14:44:01 -04:00
Linus Torvalds a1c70a756f Merge branch 'Kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/misc
* 'Kconfig' of git://git.kernel.org/pub/scm/linux/kernel/git/adobriyan/misc: (36 commits)
  fs/Kconfig: move 9p out
  fs/Kconfig: move afs out
  fs/Kconfig: move coda out
  fs/Kconfig: move the rest of ncpfs out
  fs/Kconfig: move smbfs out
  fs/Kconfig: move sunrpc out
  fs/Kconfig: move nfsd out
  fs/Kconfig: move nfs out
  fs/Kconfig: move ufs out
  fs/Kconfig: move sysv out
  fs/Kconfig: move romfs out
  fs/Kconfig: move qnx4 out
  fs/Kconfig: move hpfs out
  fs/Kconfig: move omfs out
  fs/Kconfig: move minix out
  fs/Kconfig: move vxfs out
  fs/Kconfig: move squashfs out
  fs/Kconfig: move cramfs out
  fs/Kconfig: move efs out
  fs/Kconfig: move bfs out
  ...
2009-01-26 10:08:50 -08:00
Miklos Szeredi f6d47a1761 fuse: fix poll notify
Move fuse_copy_finish() to before calling fuse_notify_poll_wakeup().
This is not a big issue because fuse_notify_poll_wakeup() should be
atomic, but it's cleaner this way, and later uses of notification will
need to be able to finish the copying before performing some actions.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-01-26 15:00:59 +01:00
Miklos Szeredi 26c3679101 fuse: destroy bdi on umount
If a fuse filesystem is unmounted but the device file descriptor
remains open and a new mount reuses the old device number, then the
mount fails with EEXIST and the following warning is printed in the
kernel log:

  WARNING: at fs/sysfs/dir.c:462 sysfs_add_one+0x35/0x3d()
  sysfs: duplicate filename '0:15' can not be created

The cause is that the bdi belonging to the fuse filesystem was
destoryed only after the device file was released.  Fix this by
calling bdi_destroy() from fuse_put_super() instead.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
2009-01-26 15:00:59 +01:00
Miklos Szeredi c2b8f00690 fuse: fuse_fill_super error handling cleanup
Clean up error handling for the whole of fuse_fill_super() function.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2009-01-26 15:00:58 +01:00
Miklos Szeredi 3ddf1e7f57 fuse: fix missing fput on error
Fix the leaking file reference if allocation or initialization of
fuse_conn failed.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
2009-01-26 15:00:58 +01:00
Dan Carpenter bb875b38dc fuse: fix NULL deref in fuse_file_alloc()
ff is set to NULL and then dereferenced on line 65.  Compile tested only.

Signed-off-by: Dan Carpenter <error27@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
2009-01-26 15:00:58 +01:00
Alexey Dobriyan 3ef7784e47 fs/Kconfig: move fuse out
Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
2009-01-22 13:15:55 +03:00
Linus Torvalds 5fec8bdbf9 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: clean up annotations of fc->lock
  fuse: fix sparse warning in ioctl
  fuse: update interface version
  fuse: add fuse_conn->release()
  fuse: separate out fuse_conn_init() from new_conn()
  fuse: add fuse_ prefix to several functions
  fuse: implement poll support
  fuse: implement unsolicited notification
  fuse: add file kernel handle
  fuse: implement ioctl support
  fuse: don't let fuse_req->end() put the base reference
  fuse: move FUSE_MINOR to miscdevice.h
  fuse: style fixes
2009-01-06 17:01:20 -08:00
Nick Piggin 54566b2c15 fs: symlink write_begin allocation context fix
With the write_begin/write_end aops, page_symlink was broken because it
could no longer pass a GFP_NOFS type mask into the point where the
allocations happened.  They are done in write_begin, which would always
assume that the filesystem can be entered from reclaim.  This bug could
cause filesystem deadlocks.

The funny thing with having a gfp_t mask there is that it doesn't really
allow the caller to arbitrarily tinker with the context in which it can be
called.  It couldn't ever be GFP_ATOMIC, for example, because it needs to
take the page lock.  The only thing any callers care about is __GFP_FS
anyway, so turn that into a single flag.

Add a new flag for write_begin, AOP_FLAG_NOFS.  Filesystems can now act on
this flag in their write_begin function.  Change __grab_cache_page to
accept a nofs argument as well, to honour that flag (while we're there,
change the name to grab_cache_page_write_begin which is more instructive
and does away with random leading underscores).

This is really a more flexible way to go in the end anyway -- if a
filesystem happens to want any extra allocations aside from the pagecache
ones in ints write_begin function, it may now use GFP_KERNEL (rather than
GFP_NOFS) for common case allocations (eg.  ocfs2_alloc_write_ctxt, for a
random example).

[kosaki.motohiro@jp.fujitsu.com: fix ubifs]
[kosaki.motohiro@jp.fujitsu.com: fix fuse]
Signed-off-by: Nick Piggin <npiggin@suse.de>
Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Cc: <stable@kernel.org>		[2.6.28.x]
Signed-off-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
[ Cleaned up the calling convention: just pass in the AOP flags
  untouched to the grab_cache_page_write_begin() function.  That
  just simplifies everybody, and may even allow future expansion of the
  logic.   - Linus ]
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2009-01-04 13:33:20 -08:00
Harvey Harrison 5d9ec854bf fuse: clean up annotations of fc->lock
Makes the existing annotations match the more common one per line style
and adds a few missing annotations.

Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-12-02 14:49:42 +01:00
Miklos Szeredi c9f0523d88 fuse: fix sparse warning in ioctl
Fix sparse warning:

  CHECK   fs/fuse/file.c
fs/fuse/file.c:1615:17: warning: incorrect type in assignment (different address spaces)
fs/fuse/file.c:1615:17:    expected void [noderef] <asn:1>*iov_base
fs/fuse/file.c:1615:17:    got void *<noident>

This was introduced by "fuse: implement ioctl support".

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-12-02 14:49:42 +01:00
Tejun Heo 43901aabd7 fuse: add fuse_conn->release()
Add fuse_conn->release() so that fuse_conn can be embedded in other
structures.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:56 +01:00
Tejun Heo 0d179aa592 fuse: separate out fuse_conn_init() from new_conn()
Separate out fuse_conn_init() from new_conn() and while at it
initialize fuse_conn->entry during conn initialization.

This will be used by CUSE.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
Tejun Heo b93f858ab2 fuse: add fuse_ prefix to several functions
Add fuse_ prefix to request_send*() and get_root_inode() as some of
those functions will be exported for CUSE.  With or without CUSE
export, having the function names scoped is a good idea for
debuggability.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
Tejun Heo 95668a69a4 fuse: implement poll support
Implement poll support.  Polled files are indexed using kh in a RB
tree rooted at fuse_conn->polled_files.

Client should send FUSE_NOTIFY_POLL notification once after processing
FUSE_POLL which has FUSE_POLL_SCHEDULE_NOTIFY set.  Sending
notification unconditionally after the latest poll or everytime file
content might have changed is inefficient but won't cause malfunction.

fuse_file_poll() can sleep and requires patches from the following
thread which allows f_op->poll() to sleep.

  http://thread.gmane.org/gmane.linux.kernel/726176

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00
Tejun Heo 8599396b50 fuse: implement unsolicited notification
Clients always used to write only in response to read requests.  To
implement poll efficiently, clients should be able to issue
unsolicited notifications.  This patch implements basic notification
support.

Zero fuse_out_header.unique is now accepted and considered unsolicited
notification and the error field contains notification code.  This
patch doesn't implement any actual notification.

Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2008-11-26 12:03:55 +01:00