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  1. 24 8月, 2011 1 次提交
  3. 23 3月, 2011 1 次提交
  5. 21 3月, 2011 1 次提交
  7. 08 12月, 2010 2 次提交
    • M
      fuse: allow batching of FORGET requests · 02c048b9
      由 Miklos Szeredi 提交于 
      Terje Malmedal reports that a fuse filesystem with 32 million inodes
on a machine with lots of memory can take up to 30 minutes to process
FORGET requests when all those inodes are evicted from the icache.

To solve this, create a BATCH_FORGET request that allows up to about
8000 FORGET requests to be sent in a single message.

This request is only sent if userspace supports interface version 7.16
or later, otherwise fall back to sending individual FORGET messages.
Reported-by: NTerje Malmedal <terje.malmedal@usit.uio.no>
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      02c048b9
    • M
      fuse: separate queue for FORGET requests · 07e77dca
      由 Miklos Szeredi 提交于 
      Terje Malmedal reports that a fuse filesystem with 32 million inodes
on a machine with lots of memory can go unresponsive for up to 30
minutes when all those inodes are evicted from the icache.

The reason is that FORGET messages, sent when the inode is evicted,
are queued up together with regular filesystem requests, and while the
huge queue of FORGET messages are processed no other filesystem
operation can proceed.

Since a full fuse request structure is allocated for each inode, these
take up quite a bit of memory as well.

To solve these issues, create a slim 'fuse_forget_link' structure
containing just the minimum of information required to send the FORGET
request and chain these on a separate queue.

When userspace is asking for a request make sure that FORGET and
non-FORGET requests are selected fairly: for each 8 non-FORGET allow
16 FORGET requests.  This will make sure FORGETs do not pile up, yet
other requests are also allowed to proceed while the queued FORGETs
are processed.
Reported-by: NTerje Malmedal <terje.malmedal@usit.uio.no>
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      07e77dca
  9. 28 10月, 2010 1 次提交
  11. 27 10月, 2010 2 次提交
  13. 04 10月, 2010 1 次提交
  15. 07 9月, 2010 2 次提交
    • M
      fuse: fix lock annotations · b9ca67b2
      由 Miklos Szeredi 提交于 
      Sparse doesn't understand lock annotations of the form
__releases(&foo->lock).  Change them to __releases(foo->lock).  Same
for __acquires().
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      b9ca67b2
    • M
      fuse: flush background queue on connection close · 595afaf9
      由 Miklos Szeredi 提交于 
      David Bartly reported that fuse can hang in fuse_get_req_nofail() when
the connection to the filesystem server is no longer active.

If bg_queue is not empty then flush_bg_queue() called from
request_end() can put more requests on to the pending queue.  If this
happens while ending requests on the processing queue then those
background requests will be queued to the pending list and never
ended.

Another problem is that fuse_dev_release() didn't wake up processes
sleeping on blocked_waitq.

Solve this by:

 a) flushing the background queue before calling end_requests() on the
    pending and processing queues

 b) setting blocked = 0 and waking up processes waiting on
    blocked_waitq()

Thanks to David for an excellent bug report.
Reported-by: NDavid Bartley <andareed@gmail.com>
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
      595afaf9
  17. 12 7月, 2010 3 次提交
    • M
      fuse: add retrieve request · 2d45ba38
      由 Miklos Szeredi 提交于 
      Userspace filesystem can request data to be retrieved from the inode's
mapping.  This request is synchronous and the retrieved data is queued
as a new request.  If the write to the fuse device returns an error
then the retrieve request was not completed and a reply will not be
sent.

Only present pages are returned in the retrieve reply.  Retrieving
stops when it finds a non-present page and only data prior to that is
returned.

This request doesn't change the dirty state of pages.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      2d45ba38
    • M
      fuse: add store request · a1d75f25
      由 Miklos Szeredi 提交于 
      Userspace filesystem can request data to be stored in the inode's
mapping.  This request is synchronous and has no reply.  If the write
to the fuse device returns an error then the store request was not
fully completed (but may have updated some pages).

If the stored data overflows the current file size, then the size is
extended, similarly to a write(2) on the filesystem.

Pages which have been completely stored are marked uptodate.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      a1d75f25
    • M
      fuse: don't use atomic kmap · 7909b1c6
      由 Miklos Szeredi 提交于 
      Don't use atomic kmap for mapping userspace buffers in device
read/write/splice.

This is necessary because the next patch (adding store notify)
requires that caller of fuse_copy_page() may sleep between
invocations.  The simplest way to ensure this is to change the atomic
kmaps to non-atomic ones.

Thankfully architectures where kmap() is not a no-op are going out of
fashion, so we can ignore the (probably negligible) performance impact
of this change.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      7909b1c6
  19. 26 5月, 2010 1 次提交
    • K
      driver core: add devname module aliases to allow module on-demand auto-loading · 578454ff
      由 Kay Sievers 提交于 
      This adds:
  alias: devname:<name>
to some common kernel modules, which will allow the on-demand loading
of the kernel module when the device node is accessed.

Ideally all these modules would be compiled-in, but distros seems too
much in love with their modularization that we need to cover the common
cases with this new facility. It will allow us to remove a bunch of pretty
useless init scripts and modprobes from init scripts.

The static device node aliases will be carried in the module itself. The
program depmod will extract this information to a file in the module directory:
  $ cat /lib/modules/2.6.34-00650-g537b60d1-dirty/modules.devname
  # Device nodes to trigger on-demand module loading.
  microcode cpu/microcode c10:184
  fuse fuse c10:229
  ppp_generic ppp c108:0
  tun net/tun c10:200
  dm_mod mapper/control c10:235

Udev will pick up the depmod created file on startup and create all the
static device nodes which the kernel modules specify, so that these modules
get automatically loaded when the device node is accessed:
  $ /sbin/udevd --debug
  ...
  static_dev_create_from_modules: mknod '/dev/cpu/microcode' c10:184
  static_dev_create_from_modules: mknod '/dev/fuse' c10:229
  static_dev_create_from_modules: mknod '/dev/ppp' c108:0
  static_dev_create_from_modules: mknod '/dev/net/tun' c10:200
  static_dev_create_from_modules: mknod '/dev/mapper/control' c10:235
  udev_rules_apply_static_dev_perms: chmod '/dev/net/tun' 0666
  udev_rules_apply_static_dev_perms: chmod '/dev/fuse' 0666

A few device nodes are switched to statically allocated numbers, to allow
the static nodes to work. This might also useful for systems which still run
a plain static /dev, which is completely unsafe to use with any dynamic minor
numbers.

Note:
The devname aliases must be limited to the *common* and *single*instance*
device nodes, like the misc devices, and never be used for conceptually limited
systems like the loop devices, which should rather get fixed properly and get a
control node for losetup to talk to, instead of creating a random number of
device nodes in advance, regardless if they are ever used.

This facility is to hide the mess distros are creating with too modualized
kernels, and just to hide that these modules are not compiled-in, and not to
paper-over broken concepts. Thanks! :)

Cc: Greg Kroah-Hartman <gregkh@suse.de>
Cc: David S. Miller <davem@davemloft.net>
Cc: Miklos Szeredi <miklos@szeredi.hu>
Cc: Chris Mason <chris.mason@oracle.com>
Cc: Alasdair G Kergon <agk@redhat.com>
Cc: Tigran Aivazian <tigran@aivazian.fsnet.co.uk>
Cc: Ian Kent <raven@themaw.net>
Signed-Off-By: NKay Sievers <kay.sievers@vrfy.org>
Signed-off-by: NGreg Kroah-Hartman <gregkh@suse.de>
      578454ff
  21. 25 5月, 2010 4 次提交
    • M
      fuse: support splice() reading from fuse device · c3021629
      由 Miklos Szeredi 提交于 
      Allow userspace filesystem implementation to use splice() to read from
the fuse device.

The userspace filesystem can now transfer data coming from a WRITE
request to an arbitrary file descriptor (regular file, block device or
socket) without having to go through a userspace buffer.

The semantics of using splice() to read messages are:

 1)  with a single splice() call move the whole message from the fuse
     device to a temporary pipe
 2)  read the header from the pipe and determine the message type
 3a) if message is a WRITE then splice data from pipe to destination
 3b) else read rest of message to userspace buffer
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      c3021629
    • M
      fuse: allow splice to move pages · ce534fb0
      由 Miklos Szeredi 提交于 
      When splicing buffers to the fuse device with SPLICE_F_MOVE, try to
move pages from the pipe buffer into the page cache.  This allows
populating the fuse filesystem's cache without ever touching the page
contents, i.e. zero copy read capability.

The following steps are performed when trying to move a page into the
page cache:

 - buf->ops->confirm() to make sure the new page is uptodate
 - buf->ops->steal() to try to remove the new page from it's previous place
 - remove_from_page_cache() on the old page
 - add_to_page_cache_locked() on the new page

If any of the above steps fail (non fatally) then the code falls back
to copying the page.  In particular ->steal() will fail if there are
external references (other than the page cache and the pipe buffer) to
the page.

Also since the remove_from_page_cache() + add_to_page_cache_locked()
are non-atomic it is possible that the page cache is repopulated in
between the two and add_to_page_cache_locked() will fail.  This could
be fixed by creating a new atomic replace_page_cache_page() function.

fuse_readpages_end() needed to be reworked so it works even if
page->mapping is NULL for some or all pages which can happen if the
add_to_page_cache_locked() failed.

A number of sanity checks were added to make sure the stolen pages
don't have weird flags set, etc...  These could be moved into generic
splice/steal code.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      ce534fb0
    • M
      fuse: support splice() writing to fuse device · dd3bb14f
      由 Miklos Szeredi 提交于 
      Allow userspace filesystem implementation to use splice() to write to
the fuse device.  The semantics of using splice() are:

 1) buffer the message header and data in a temporary pipe
 2) with a *single* splice() call move the message from the temporary pipe
    to the fuse device

The READ reply message has the most interesting use for this, since
now the data from an arbitrary file descriptor (which could be a
regular file, a block device or a socket) can be tranferred into the
fuse device without having to go through a userspace buffer.  It will
also allow zero copy moving of pages.

One caveat is that the protocol on the fuse device requires the length
of the whole message to be written into the header.  But the length of
the data transferred into the temporary pipe may not be known in
advance.  The current library implementation works around this by
using vmplice to write the header and modifying the header after
splicing the data into the pipe (error handling omitted):

	struct fuse_out_header out;

	iov.iov_base = &out;
	iov.iov_len = sizeof(struct fuse_out_header);
	vmsplice(pip[1], &iov, 1, 0);
	len = splice(input_fd, input_offset, pip[1], NULL, len, 0);
	/* retrospectively modify the header: */
	out.len = len + sizeof(struct fuse_out_header);
	splice(pip[0], NULL, fuse_chan_fd(req->ch), NULL, out.len, flags);

This works since vmsplice only saves a pointer to the data, it does
not copy the data itself.

Since pipes are currently limited to 16 pages and messages need to be
spliced atomically, the length of the data is limited to 15 pages (or
60kB for 4k pages).
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      dd3bb14f
    • M
      fuse: use get_user_pages_fast() · 1bf94ca7
      由 Miklos Szeredi 提交于 
      Replace uses of get_user_pages() with get_user_pages_fast().  It looks
nicer and should be faster in most cases.
Signed-off-by: NMiklos Szeredi <mszeredi@suse.cz>
      1bf94ca7
  23. 05 2月, 2010 2 次提交
  25. 12 7月, 2009 1 次提交
  27. 11 7月, 2009 2 次提交
  29. 07 7月, 2009 1 次提交
  31. 01 7月, 2009 2 次提交
    • J
      fuse: invalidation reverse calls · 3b463ae0
      由 John Muir 提交于 
      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: NMiklos Szeredi <mszeredi@suse.cz>
      3b463ae0
    • C
      fuse: fix return value of fuse_dev_write() · b4c458b3
      由 Csaba Henk 提交于 
      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: NMiklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
      b4c458b3
  33. 28 4月, 2009 2 次提交
  35. 26 1月, 2009 2 次提交
    • M
      fuse: fix poll notify · f6d47a17
      由 Miklos Szeredi 提交于 
      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: NMiklos Szeredi <mszeredi@suse.cz>
      f6d47a17
    • M
      fuse: destroy bdi on umount · 26c36791
      由 Miklos Szeredi 提交于 
      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: NMiklos Szeredi <mszeredi@suse.cz>
CC: stable@kernel.org
      26c36791
  37. 02 12月, 2008 1 次提交
  39. 26 11月, 2008 5 次提交
  41. 14 11月, 2008 1 次提交
  43. 02 11月, 2008 1 次提交
    • A
      saner FASYNC handling on file close · 233e70f4
      由 Al Viro 提交于 
      As it is, all instances of ->release() for files that have ->fasync()
need to remember to evict file from fasync lists; forgetting that
creates a hole and we actually have a bunch that *does* forget.

So let's keep our lives simple - let __fput() check FASYNC in
file->f_flags and call ->fasync() there if it's been set.  And lose that
crap in ->release() instances - leaving it there is still valid, but we
don't have to bother anymore.
Signed-off-by: NAl Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>
      233e70f4
  45. 30 4月, 2008 1 次提交