Commit Graph

520289 Commits

Author SHA1 Message Date
Miklos Szeredi
82cbdcd320 fuse: cleanup fuse_dev_do_read()
- locked list_add() + list_del_init() cancel out

 - common handling of case when request is ended here in the read phase

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:05 +02:00
Miklos Szeredi
f377cb799e fuse: move list_del_init() from request_end() into callers
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:04 +02:00
Miklos Szeredi
e96edd94d0 fuse: duplicate ->connected in pqueue
This will allow checking ->connected just with the processing queue lock.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:04 +02:00
Miklos Szeredi
3a2b5b9cd9 fuse: separate out processing queue
This is just two fields: fc->io and fc->processing.

This patch just rearranges the fields, no functional change.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:04 +02:00
Miklos Szeredi
5250921bb0 fuse: simplify request_wait()
wait_event_interruptible_exclusive_locked() will do everything
request_wait() does, so replace it.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:03 +02:00
Miklos Szeredi
fd22d62ed0 fuse: no fc->lock for iqueue parts
Remove fc->lock protection from input queue members, now protected by
fiq->waitq.lock.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:03 +02:00
Miklos Szeredi
8f7bb368db fuse: allow interrupt queuing without fc->lock
Interrupt is only queued after the request has been sent to userspace.
This is either done in request_wait_answer() or fuse_dev_do_read()
depending on which state the request is in at the time of the interrupt.
If it's not yet sent, then queuing the interrupt is postponed until the
request is read.  Otherwise (the request has already been read and is
waiting for an answer) the interrupt is queued immedidately.

We want to call queue_interrupt() without fc->lock protection, in which
case there can be a race between the two functions:

 - neither of them queue the interrupt (thinking the other one has already
   done it).

 - both of them queue the interrupt

The first one is prevented by adding memory barriers, the second is
prevented by checking (under fiq->waitq.lock) if the interrupt has already
been queued.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:03 +02:00
Miklos Szeredi
4ce6081260 fuse: iqueue locking
Use fiq->waitq.lock for protecting members of struct fuse_iqueue and
FR_PENDING request flag, previously protected by fc->lock.

Following patches will remove fc->lock protection from these members.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:02 +02:00
Miklos Szeredi
ef75925886 fuse: dev read: split list_move
Different lists will need different locks.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:02 +02:00
Miklos Szeredi
8c91189a2a fuse: abort: group iqueue accesses
Rearrange fuse_abort_conn() so that input queue accesses are grouped
together.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:02 +02:00
Miklos Szeredi
e16714d875 fuse: duplicate ->connected in iqueue
This will allow checking ->connected just with the input queue lock.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:01 +02:00
Miklos Szeredi
f88996a933 fuse: separate out input queue
The input queue contains normal requests (fc->pending), forgets
(fc->forget_*) and interrupts (fc->interrupts).  There's also fc->waitq and
fc->fasync for waking up the readers of the fuse device when a request is
available.

The fc->reqctr is also moved to the input queue (assigned to the request
when the request is added to the input queue.

This patch just rearranges the fields, no functional change.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:01 +02:00
Miklos Szeredi
33e14b4dfd fuse: req state use flags
Use flags for representing the state in fuse_req.  This is needed since
req->list will be protected by different locks in different states, hence
we'll want the state itself to be split into distinct bits, each protected
with the relevant lock in that state.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:01 +02:00
Miklos Szeredi
7a3b2c7547 fuse: simplify req states
FUSE_REQ_INIT is actually the same state as FUSE_REQ_PENDING and
FUSE_REQ_READING and FUSE_REQ_WRITING can be merged into a common
FUSE_REQ_IO state.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:00 +02:00
Miklos Szeredi
c47752673a fuse: don't hold lock over request_wait_answer()
Only hold fc->lock over sections of request_wait_answer() that actually
need it.  If wait_event_interruptible() returns zero, it means that the
request finished.  Need to add memory barriers, though, to make sure that
all relevant data in the request is synchronized.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01 16:26:00 +02:00
Miklos Szeredi
7d2e0a099c fuse: simplify unique ctr
Since it's a 64bit counter, it's never gonna wrap around.  Remove code
dealing with that possibility.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:26:00 +02:00
Miklos Szeredi
41f982747e fuse: rework abort
Splice fc->pending and fc->processing lists into a common kill list while
holding fc->lock.

By the time we release fc->lock, pending and processing lists are empty and
the io list contains only locked requests.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:59 +02:00
Miklos Szeredi
b716d42538 fuse: fold helpers into abort
Fold end_io_requests() and end_queued_requests() into fuse_abort_conn().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:59 +02:00
Miklos Szeredi
dc00809a53 fuse: use per req lock for lock/unlock_request()
Reuse req->waitq.lock for protecting FR_ABORTED and FR_LOCKED flags.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
Miklos Szeredi
825d6d3395 fuse: req use bitops
Finer grained locking will mean there's no single lock to protect
modification of bitfileds in fuse_req.

So move to using bitops.  Can use the non-atomic variants for those which
happen while the request definitely has only one reference.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
Miklos Szeredi
0d8e84b043 fuse: simplify request abort
- don't end the request while req->locked is true

 - make unlock_request() return an error if the connection was aborted

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:58 +02:00
Miklos Szeredi
ccd0a0bd16 fuse: call fuse_abort_conn() in dev release
fuse_abort_conn() does all the work done by fuse_dev_release() and more.
"More" consists of:

	end_io_requests(fc);
	wake_up_all(&fc->waitq);
	kill_fasync(&fc->fasync, SIGIO, POLL_IN);

All of which should be no-op (WARN_ON's added).

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:57 +02:00
Miklos Szeredi
f0139aa819 fuse: fold fuse_request_send_nowait() into single caller
And the same with fuse_request_send_nowait_locked().

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:57 +02:00
Miklos Szeredi
de15522646 fuse: check conn_error earlier
fc->conn_error is set once in FUSE_INIT reply and never cleared.  Check it
in request allocation, there's no sense in doing all the preparation if
sending will surely fail.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:57 +02:00
Miklos Szeredi
5437f24172 fuse: account as waiting before queuing for background
Move accounting of fc->num_waiting to the point where the request actually
starts waiting.  This is earlier than the current queue_request() for
background requests, since they might be waiting on the fc->bg_queue before
being queued on fc->pending.

Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01 16:25:56 +02:00