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path: root/fs/fuse/dev.c
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2017-11-15mm: remove cold parameter for release_pagesMel Gorman
All callers of release_pages claim the pages being released are cache hot. As no one cares about the hotness of pages being released to the allocator, just ditch the parameter. No performance impact is expected as the overhead is marginal. The parameter is removed simply because it is a bit stupid to have a useless parameter copied everywhere. Link: http://lkml.kernel.org/r/20171018075952.10627-7-mgorman@techsingularity.net Signed-off-by: Mel Gorman <mgorman@techsingularity.net> Acked-by: Vlastimil Babka <vbabka@suse.cz> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dave Chinner <david@fromorbit.com> Cc: Dave Hansen <dave.hansen@intel.com> Cc: Jan Kara <jack@suse.cz> Cc: Johannes Weiner <hannes@cmpxchg.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2017-10-25locking/atomics: COCCINELLE/treewide: Convert trivial ACCESS_ONCE() patterns ↵Mark Rutland
to READ_ONCE()/WRITE_ONCE() Please do not apply this to mainline directly, instead please re-run the coccinelle script shown below and apply its output. For several reasons, it is desirable to use {READ,WRITE}_ONCE() in preference to ACCESS_ONCE(), and new code is expected to use one of the former. So far, there's been no reason to change most existing uses of ACCESS_ONCE(), as these aren't harmful, and changing them results in churn. However, for some features, the read/write distinction is critical to correct operation. To distinguish these cases, separate read/write accessors must be used. This patch migrates (most) remaining ACCESS_ONCE() instances to {READ,WRITE}_ONCE(), using the following coccinelle script: ---- // Convert trivial ACCESS_ONCE() uses to equivalent READ_ONCE() and // WRITE_ONCE() // $ make coccicheck COCCI=/home/mark/once.cocci SPFLAGS="--include-headers" MODE=patch virtual patch @ depends on patch @ expression E1, E2; @@ - ACCESS_ONCE(E1) = E2 + WRITE_ONCE(E1, E2) @ depends on patch @ expression E; @@ - ACCESS_ONCE(E) + READ_ONCE(E) ---- Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: davem@davemloft.net Cc: linux-arch@vger.kernel.org Cc: mpe@ellerman.id.au Cc: shuah@kernel.org Cc: snitzer@redhat.com Cc: thor.thayer@linux.intel.com Cc: tj@kernel.org Cc: viro@zeniv.linux.org.uk Cc: will.deacon@arm.com Link: http://lkml.kernel.org/r/1508792849-3115-19-git-send-email-paulmck@linux.vnet.ibm.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-09-12fuse: allow server to run in different pid_nsMiklos Szeredi
Commit 0b6e9ea041e6 ("fuse: Add support for pid namespaces") broke Sandstorm.io development tools, which have been sending FUSE file descriptors across PID namespace boundaries since early 2014. The above patch added a check that prevented I/O on the fuse device file descriptor if the pid namespace of the reader/writer was different from the pid namespace of the mounter. With this change passing the device file descriptor to a different pid namespace simply doesn't work. The check was added because pids are transferred to/from the fuse userspace server in the namespace registered at mount time. To fix this regression, remove the checks and do the following: 1) the pid in the request header (the pid of the task that initiated the filesystem operation) is translated to the reader's pid namespace. If a mapping doesn't exist for this pid, then a zero pid is used. Note: even if a mapping would exist between the initiator task's pid namespace and the reader's pid namespace the pid will be zero if either mapping from initator's to mounter's namespace or mapping from mounter's to reader's namespace doesn't exist. 2) The lk.pid value in setlk/setlkw requests and getlk reply is left alone. Userspace should not interpret this value anyway. Also allow the setlk/setlkw operations if the pid of the task cannot be represented in the mounter's namespace (pid being zero in that case). Reported-by: Kenton Varda <kenton@sandstorm.io> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: 0b6e9ea041e6 ("fuse: Add support for pid namespaces") Cc: <stable@vger.kernel.org> # v4.12+ Cc: Eric W. Biederman <ebiederm@xmission.com> Cc: Seth Forshee <seth.forshee@canonical.com>
2017-05-10Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: "Support for pid namespaces from Seth and refcount_t work from Elena" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: Add support for pid namespaces fuse: convert fuse_conn.count from atomic_t to refcount_t fuse: convert fuse_req.count from atomic_t to refcount_t fuse: convert fuse_file.count from atomic_t to refcount_t
2017-04-20fuse: Get rid of bdi_initializedJan Kara
It is not needed anymore since bdi is initialized whenever superblock exists. CC: Miklos Szeredi <miklos@szeredi.hu> CC: linux-fsdevel@vger.kernel.org Suggested-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-20fuse: Convert to separately allocated bdiJan Kara
Allocate struct backing_dev_info separately instead of embedding it inside the superblock. This unifies handling of bdi among users. CC: Miklos Szeredi <miklos@szeredi.hu> CC: linux-fsdevel@vger.kernel.org Acked-by: Miklos Szeredi <mszeredi@redhat.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Jan Kara <jack@suse.cz> Signed-off-by: Jens Axboe <axboe@fb.com>
2017-04-18fuse: Add support for pid namespacesSeth Forshee
When the userspace process servicing fuse requests is running in a pid namespace then pids passed via the fuse fd are not being translated into that process' namespace. Translation is necessary for the pid to be useful to that process. Since no use case currently exists for changing namespaces all translations can be done relative to the pid namespace in use when fuse_conn_init() is called. For fuse this translates to mount time, and for cuse this is when /dev/cuse is opened. IO for this connection from another namespace will return errors. Requests from processes whose pid cannot be translated into the target namespace will have a value of 0 for in.h.pid. File locking changes based on previous work done by Eric Biederman. Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-04-18fuse: convert fuse_req.count from atomic_t to refcount_tElena Reshetova
refcount_t type and corresponding API should be used instead of atomic_t when the variable is used as a reference counter. This allows to avoid accidental refcounter overflows that might lead to use-after-free situations. Signed-off-by: Elena Reshetova <elena.reshetova@intel.com> Signed-off-by: Hans Liljestrand <ishkamiel@gmail.com> Signed-off-by: Kees Cook <keescook@chromium.org> Signed-off-by: David Windsor <dwindsor@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-03-02sched/headers: Prepare to move signal wakeup & sigpending methods from ↵Ingo Molnar
<linux/sched.h> into <linux/sched/signal.h> Fix up affected files that include this signal functionality via sched.h. Acked-by: Linus Torvalds <torvalds@linux-foundation.org> Cc: Mike Galbraith <efault@gmx.de> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: linux-kernel@vger.kernel.org Signed-off-by: Ingo Molnar <mingo@kernel.org>
2017-02-16fuse: fix uninitialized flags in pipe_bufferMiklos Szeredi
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: d82718e348fe ("fuse_dev_splice_read(): switch to add_to_pipe()") Cc: <stable@vger.kernel.org> # 4.9+
2017-02-15fuse: fix use after free issue in fuse_dev_do_read()Sahitya Tummala
There is a potential race between fuse_dev_do_write() and request_wait_answer() contexts as shown below: TASK 1: __fuse_request_send(): |--spin_lock(&fiq->waitq.lock); |--queue_request(); |--spin_unlock(&fiq->waitq.lock); |--request_wait_answer(): |--if (test_bit(FR_SENT, &req->flags)) <gets pre-empted after it is validated true> TASK 2: fuse_dev_do_write(): |--clears bit FR_SENT, |--request_end(): |--sets bit FR_FINISHED |--spin_lock(&fiq->waitq.lock); |--list_del_init(&req->intr_entry); |--spin_unlock(&fiq->waitq.lock); |--fuse_put_request(); |--queue_interrupt(); <request gets queued to interrupts list> |--wake_up_locked(&fiq->waitq); |--wait_event_freezable(); <as FR_FINISHED is set, it returns and then the caller frees this request> Now, the next fuse_dev_do_read(), see interrupts list is not empty and then calls fuse_read_interrupt() which tries to access the request which is already free'd and gets the below crash: [11432.401266] Unable to handle kernel paging request at virtual address 6b6b6b6b6b6b6b6b ... [11432.418518] Kernel BUG at ffffff80083720e0 [11432.456168] PC is at __list_del_entry+0x6c/0xc4 [11432.463573] LR is at fuse_dev_do_read+0x1ac/0x474 ... [11432.679999] [<ffffff80083720e0>] __list_del_entry+0x6c/0xc4 [11432.687794] [<ffffff80082c65e0>] fuse_dev_do_read+0x1ac/0x474 [11432.693180] [<ffffff80082c6b14>] fuse_dev_read+0x6c/0x78 [11432.699082] [<ffffff80081d5638>] __vfs_read+0xc0/0xe8 [11432.704459] [<ffffff80081d5efc>] vfs_read+0x90/0x108 [11432.709406] [<ffffff80081d67f0>] SyS_read+0x58/0x94 As FR_FINISHED bit is set before deleting the intr_entry with input queue lock in request completion path, do the testing of this flag and queueing atomically with the same lock in queue_interrupt(). Signed-off-by: Sahitya Tummala <stummala@codeaurora.org> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Fixes: fd22d62ed0c3 ("fuse: no fc->lock for iqueue parts") Cc: <stable@vger.kernel.org> # 4.2+
2017-01-13fuse: clear FR_PENDING flag when moving requests out of pending queueTahsin Erdogan
fuse_abort_conn() moves requests from pending list to a temporary list before canceling them. This operation races with request_wait_answer() which also tries to remove the request after it gets a fatal signal. It checks FR_PENDING flag to determine whether the request is still in the pending list. Make fuse_abort_conn() clear FR_PENDING flag so that request_wait_answer() does not remove the request from temporary list. This bug causes an Oops when trying to delete an already deleted list entry in end_requests(). Fixes: ee314a870e40 ("fuse: abort: no fc->lock needed for request ending") Signed-off-by: Tahsin Erdogan <tahsin@google.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Cc: <stable@vger.kernel.org> # 4.2+
2016-10-07Merge branch 'work.splice_read' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull VFS splice updates from Al Viro: "There's a bunch of branches this cycle, both mine and from other folks and I'd rather send pull requests separately. This one is the conversion of ->splice_read() to ITER_PIPE iov_iter (and introduction of such). Gets rid of a lot of code in fs/splice.c and elsewhere; there will be followups, but these are for the next cycle... Some pipe/splice-related cleanups from Miklos in the same branch as well" * 'work.splice_read' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: pipe: fix comment in pipe_buf_operations pipe: add pipe_buf_steal() helper pipe: add pipe_buf_confirm() helper pipe: add pipe_buf_release() helper pipe: add pipe_buf_get() helper relay: simplify relay_file_read() switch default_file_splice_read() to use of pipe-backed iov_iter switch generic_file_splice_read() to use of ->read_iter() new iov_iter flavour: pipe-backed fuse_dev_splice_read(): switch to add_to_pipe() skb_splice_bits(): get rid of callback new helper: add_to_pipe() splice: lift pipe_lock out of splice_to_pipe() splice: switch get_iovec_page_array() to iov_iter splice_to_pipe(): don't open-code wakeup_pipe_readers() consistent treatment of EFAULT on O_DIRECT read/write
2016-10-05pipe: add pipe_buf_steal() helperMiklos Szeredi
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-05pipe: add pipe_buf_confirm() helperMiklos Szeredi
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-05pipe: add pipe_buf_release() helperMiklos Szeredi
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-05pipe: add pipe_buf_get() helperMiklos Szeredi
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-03fuse_dev_splice_read(): switch to add_to_pipe()Al Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-03splice: lift pipe_lock out of splice_to_pipe()Al Viro
* splice_to_pipe() stops at pipe overflow and does *not* take pipe_lock * ->splice_read() instances do the same * vmsplice_to_pipe() and do_splice() (ultimate callers of splice_to_pipe()) arrange for waiting, looping, etc. themselves. That should make pipe_lock the outermost one. Unfortunately, existing rules for the amount passed by vmsplice_to_pipe() and do_splice() are quite ugly _and_ userland code can be easily broken by changing those. It's not even "no more than the maximal capacity of this pipe" - it's "once we'd fed pipe->nr_buffers pages into the pipe, leave instead of waiting". Considering how poorly these rules are documented, let's try "wait for some space to appear, unless given SPLICE_F_NONBLOCK, then push into pipe and if we run into overflow, we are done". Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-10-01fuse: remove duplicate cs->offset assignmentMiklos Szeredi
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-07-29Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse Pull fuse updates from Miklos Szeredi: "This fixes error propagation from writeback to fsync/close for writeback cache mode as well as adding a missing capability flag to the INIT message. The rest are cleanups. (The commits are recent but all the code actually sat in -next for a while now. The recommits are due to conflict avoidance and the addition of Cc: stable@...)" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/fuse: fuse: use filemap_check_errors() mm: export filemap_check_errors() to modules fuse: fix wrong assignment of ->flags in fuse_send_init() fuse: fuse_flush must check mapping->flags for errors fuse: fsync() did not return IO errors fuse: don't mess with blocking signals new helper: wait_event_killable_exclusive() fuse: improve aio directIO write performance for size extending writes
2016-07-19fuse: don't mess with blocking signalsAl Viro
just use wait_event_killable{,_exclusive}(). Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2016-06-10vfs: make the string hashes salt the hashLinus Torvalds
We always mixed in the parent pointer into the dentry name hash, but we did it late at lookup time. It turns out that we can simplify that lookup-time action by salting the hash with the parent pointer early instead of late. A few other users of our string hashes also wanted to mix in their own pointers into the hash, and those are updated to use the same mechanism. Hash users that don't have any particular initial salt can just use the NULL pointer as a no-salt. Cc: Vegard Nossum <vegard.nossum@oracle.com> Cc: George Spelvin <linux@sciencehorizons.net> Cc: Al Viro <viro@zeniv.linux.org.uk> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2016-04-04mm, fs: get rid of PAGE_CACHE_* and page_cache_{get,release} macrosKirill A. Shutemov
PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} macros were introduced *long* time ago with promise that one day it will be possible to implement page cache with bigger chunks than PAGE_SIZE. This promise never materialized. And unlikely will. We have many places where PAGE_CACHE_SIZE assumed to be equal to PAGE_SIZE. And it's constant source of confusion on whether PAGE_CACHE_* or PAGE_* constant should be used in a particular case, especially on the border between fs and mm. Global switching to PAGE_CACHE_SIZE != PAGE_SIZE would cause to much breakage to be doable. Let's stop pretending that pages in page cache are special. They are not. The changes are pretty straight-forward: - <foo> << (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - <foo> >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) -> <foo>; - PAGE_CACHE_{SIZE,SHIFT,MASK,ALIGN} -> PAGE_{SIZE,SHIFT,MASK,ALIGN}; - page_cache_get() -> get_page(); - page_cache_release() -> put_page(); This patch contains automated changes generated with coccinelle using script below. For some reason, coccinelle doesn't patch header files. I've called spatch for them manually. The only adjustment after coccinelle is revert of changes to PAGE_CAHCE_ALIGN definition: we are going to drop it later. There are few places in the code where coccinelle didn't reach. I'll fix them manually in a separate patch. Comments and documentation also will be addressed with the separate patch. virtual patch @@ expression E; @@ - E << (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ expression E; @@ - E >> (PAGE_CACHE_SHIFT - PAGE_SHIFT) + E @@ @@ - PAGE_CACHE_SHIFT + PAGE_SHIFT @@ @@ - PAGE_CACHE_SIZE + PAGE_SIZE @@ @@ - PAGE_CACHE_MASK + PAGE_MASK @@ expression E; @@ - PAGE_CACHE_ALIGN(E) + PAGE_ALIGN(E) @@ expression E; @@ - page_cache_get(E) + get_page(E) @@ expression E; @@ - page_cache_release(E) + put_page(E) Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Acked-by: Michal Hocko <mhocko@suse.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-08-16fs/fuse: fix ioctl type confusionJann Horn
fuse_dev_ioctl() performed fuse_get_dev() on a user-supplied fd, leading to a type confusion issue. Fix it by checking file->f_op. Signed-off-by: Jann Horn <jann@thejh.net> Acked-by: Miklos Szeredi <miklos@szeredi.hu> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2015-07-01fuse: separate pqueue for clonesMiklos Szeredi
Make each fuse device clone refer to a separate processing queue. The only constraint on userspace code is that the request answer must be written to the same device clone as it was read off. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01fuse: introduce per-instance fuse_dev structureMiklos Szeredi
Allow fuse device clones to refer to be distinguished. This patch just adds the infrastructure by associating a separate "struct fuse_dev" with each clone. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: device fd cloneMiklos Szeredi
Allow an open fuse device to be "cloned". Userspace can create a clone by: newfd = open("/dev/fuse", O_RDWR) ioctl(newfd, FUSE_DEV_IOC_CLONE, &oldfd); At this point newfd will refer to the same fuse connection as oldfd. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: abort: no fc->lock needed for request endingMiklos Szeredi
In fuse_abort_conn() when all requests are on private lists we no longer need fc->lock protection. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: no fc->lock for pqueue partsMiklos Szeredi
Remove fc->lock protection from processing queue members, now protected by fpq->lock. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: no fc->lock in request_end()Miklos Szeredi
No longer need to call request_end() with the connection lock held. We still protect the background counters and queue with fc->lock, so acquire it if necessary. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: cleanup request_end()Miklos Szeredi
Now that we atomically test having already done everything we no longer need other protection. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: request_end(): do onceMiklos Szeredi
When the connection is aborted it is possible that request_end() will be called twice. Use atomic test and set to do the actual ending only once. test_and_set_bit() also provides the necessary barrier semantics so no explicit smp_wmb() is necessary. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: add req flag for private listMiklos Szeredi
When an unlocked request is aborted, it is moved from fpq->io to a private list. Then, after unlocking fpq->lock, the private list is processed and the requests are finished off. To protect the private list, we need to mark the request with a flag, so if in the meantime the request is unlocked the list is not corrupted. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: pqueue lockingMiklos Szeredi
Add a fpq->lock for protecting members of struct fuse_pqueue and FR_LOCKED request flag. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: abort: group pqueue accessesMiklos Szeredi
Rearrange fuse_abort_conn() so that processing queue accesses are grouped together. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: cleanup fuse_dev_do_read()Miklos Szeredi
- 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>
2015-07-01fuse: move list_del_init() from request_end() into callersMiklos Szeredi
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2015-07-01fuse: duplicate ->connected in pqueueMiklos Szeredi
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>
2015-07-01fuse: separate out processing queueMiklos Szeredi
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>
2015-07-01fuse: simplify request_wait()Miklos Szeredi
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>
2015-07-01fuse: no fc->lock for iqueue partsMiklos Szeredi
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>
2015-07-01fuse: allow interrupt queuing without fc->lockMiklos Szeredi
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>
2015-07-01fuse: iqueue lockingMiklos Szeredi
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>
2015-07-01fuse: dev read: split list_moveMiklos Szeredi
Different lists will need different locks. Signed-off-by: Miklos Szeredi <mszeredi@suse.cz> Reviewed-by: Ashish Samant <ashish.samant@oracle.com>
2015-07-01fuse: abort: group iqueue accessesMiklos Szeredi
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>
2015-07-01fuse: duplicate ->connected in iqueueMiklos Szeredi
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>
2015-07-01fuse: separate out input queueMiklos Szeredi
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>
2015-07-01fuse: req state use flagsMiklos Szeredi
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>
2015-07-01fuse: simplify req statesMiklos Szeredi
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>