linux.git/fs/fuse, branch v2.6.16

[PATCH] fuse: fix bug in negative lookup

2006-03-01T04:53:43+00:00

If negative entries (nodeid == 0) were sent in reply to LOOKUP requests,
two bugs could be triggered:

- looking up a negative entry would return -EIO,

- revaildate on an entry which turned negative would send a FORGET
  request with zero nodeid, which would cause an abort() in the
  library.

The above would only happen if the 'negative_timeout=N' option was used,
otherwise lookups reply -ENOENT, which worked correctly.

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: fix bug in aborted fuse_release_end()

2006-02-17T21:59:27+00:00

There's a rather theoretical case of the BUG triggering in
fuse_reset_request():

  - iget() fails because of OOM after a successful CREATE_OPEN request
  - during IO on the resulting RELEASE request the connection is aborted

Fix and add warning to fuse_reset_request().

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: fix request_end() vs fuse_reset_request() race

2006-02-05T19:06:51+00:00

The last fix for this function in fact opened up a much more often
triggering race.

It was uncommented tricky code, that was buggy.  Add comment, make it less
tricky and fix bug.

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: fix async read for legacy filesystems

2006-02-01T16:53:09+00:00

While asynchronous reads mean a performance improvement in most cases, if
the filesystem assumed that reads are synchronous, then async reads may
degrade performance (filesystem may receive reads out of order, which can
confuse it's own readahead logic).

With sshfs a 1.5 to 4 times slowdown can be measured.

There's also a need for userspace filesystems to know whether asynchronous
reads are supported by the kernel or not.

To achive these, negotiate in the INIT request whether async reads will be
used and the maximum readahead value.  Update interface version to 7.6

If userspace uses a version earlier than 7.6, then disable async reads, and
set maximum readahead value to the maximum read size, as done in previous
versions.

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: fix bitfield race

2006-01-17T07:15:31+00:00

Fix race in setting bitfields of fuse_conn.  Spotted by Andrew Morton.

The two fields ->connected and ->mounted were always changed with the
fuse_lock held.  But other bitfields in the same structure were changed
without the lock.  In theory this could lead to losing the assignment of
even the ones under lock.  The chosen solution is to change these two
fields to be a full unsigned type.  The other bitfields aren't "important"
enough to warrant the extra complexity of full locking or changing them to
bitops.

For all bitfields document why they are safe wrt. concurrent
assignments.

Also make the initialization of the 'num_waiting' atomic counter explicit.

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: use asynchronous READ requests for readpages

2006-01-17T07:15:31+00:00

This patch changes fuse_readpages() to send READ requests asynchronously.

This makes it possible for userspace filesystems to utilize the kernel
readahead logic instead of having to implement their own (resulting in double
caching).

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: READ request initialization

2006-01-17T07:15:31+00:00

Add a separate function for filling in the READ request.  This will make it
possible to send asynchronous READ requests as well as synchronous ones.

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: move INIT handling to inode.c

2006-01-17T07:15:31+00:00

Now the INIT requests can be completely handled in inode.c and the
fuse_send_init() function need not be global any more.

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: add asynchronous request support

2006-01-17T07:15:31+00:00

Add possibility for requests to run asynchronously and call an 'end' callback
when finished.

With this, the special handling of the INIT and RELEASE requests can be
cleaned up too.

Signed-off-by: Miklos Szeredi 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

[PATCH] fuse: add connection aborting

2006-01-17T07:15:30+00:00

Add ability to abort a filesystem connection.

With the introduction of asynchronous reads, the ability to interrupt any
request is not enough to dissolve deadlocks, since now waiting for the request
completion (page unlocked) is independent of the actual request, so in a
deadlock all threads will be uninterruptible.

The solution is to make it possible to abort all requests, even those
currently undergoing I/O to/from userspace.  The natural interface for this is
'mount -f mountpoint', but that only works as long as the filesystem is
attached.  So also add an 'abort' attribute to the sysfs view of the
connection.

Signed-off-by: Miklos Szeredi 
Cc: Greg KH 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds