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2020-02-06fuse: use true,false for bool variablezhengbin
Fixes coccicheck warning: fs/fuse/readdir.c:335:1-19: WARNING: Assignment of 0/1 to bool variable fs/fuse/file.c:1398:2-19: WARNING: Assignment of 0/1 to bool variable fs/fuse/file.c:1400:2-20: WARNING: Assignment of 0/1 to bool variable fs/fuse/cuse.c:454:1-20: WARNING: Assignment of 0/1 to bool variable fs/fuse/cuse.c:455:1-19: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:497:2-17: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:504:2-23: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:511:2-22: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:518:2-23: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:522:2-26: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:526:2-18: WARNING: Assignment of 0/1 to bool variable fs/fuse/inode.c:1000:1-20: WARNING: Assignment of 0/1 to bool variable Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-24fuse: fix memleak in cuse_channel_openzhengbin
If cuse_send_init fails, need to fuse_conn_put cc->fc. cuse_channel_open->fuse_conn_init->refcount_set(&fc->count, 1) ->fuse_dev_alloc->fuse_conn_get ->fuse_dev_free->fuse_conn_put Fixes: cc080e9e9be1 ("fuse: introduce per-instance fuse_dev structure") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: zhengbin <zhengbin13@huawei.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-12fuse: separate fuse device allocation and installation in fuse_connVivek Goyal
As of now fuse_dev_alloc() both allocates a fuse device and installs it in fuse_conn list. fuse_dev_alloc() can fail if fuse_device allocation fails. virtio-fs needs to initialize multiple fuse devices (one per virtio queue). It initializes one fuse device as part of call to fuse_fill_super_common() and rest of the devices are allocated and installed after that. But, we can't afford to fail after calling fuse_fill_super_common() as we don't have a way to undo all the actions done by fuse_fill_super_common(). So to avoid failures after the call to fuse_fill_super_common(), pre-allocate all fuse devices early and install them into fuse connection later. This patch provides two separate helpers for fuse device allocation and fuse device installation in fuse_conn. Signed-off-by: Vivek Goyal <vgoyal@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-12fuse: add fuse_iqueue_ops callbacksStefan Hajnoczi
The /dev/fuse device uses fiq->waitq and fasync to signal that requests are available. These mechanisms do not apply to virtio-fs. This patch introduces callbacks so alternative behavior can be used. Note that queue_interrupt() changes along these lines: spin_lock(&fiq->waitq.lock); wake_up_locked(&fiq->waitq); + kill_fasync(&fiq->fasync, SIGIO, POLL_IN); spin_unlock(&fiq->waitq.lock); - kill_fasync(&fiq->fasync, SIGIO, POLL_IN); Since queue_request() and queue_forget() also call kill_fasync() inside the spinlock this should be safe. Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-10cuse: convert init to simple apiMiklos Szeredi
This is a straightforward conversion. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-09-02cuse: fix broken releaseMiklos Szeredi
The inode parameter in cuse_release() is likely *not* a fuse inode. It's a small wonder it didn't blow up until now. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-06-05treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428Thomas Gleixner
Based on 1 normalized pattern(s): this file is released under the gplv2 extracted by the scancode license scanner the SPDX license identifier GPL-2.0-only has been chosen to replace the boilerplate/reference in 68 file(s). Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Reviewed-by: Armijn Hemel <armijn@tjaldur.nl> Reviewed-by: Allison Randal <allison@lohutok.net> Cc: linux-spdx@vger.kernel.org Link: https://lkml.kernel.org/r/20190531190114.292346262@linutronix.de Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-04-24fuse: convert printk -> pr_*Kirill Smelkov
Functions, like pr_err, are a more modern variant of printing compared to printk. They could be used to denoise sources by using needed level in the print function name, and by automatically inserting per-driver / function / ... print prefix as defined by pr_fmt macro. pr_* are also said to be used in Documentation/process/coding-style.rst and more recent code - for example overlayfs - uses them instead of printk. Convert CUSE and FUSE to use the new pr_* functions. CUSE output stays completely unchanged, while FUSE output is amended a bit for "trying to steal weird page" warning - the second line now comes also with "fuse:" prefix. I hope it is ok. Suggested-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Kirill Smelkov <kirr@nexedi.com> Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: clean up abortedMiklos Szeredi
The only caller that needs fc->aborted set is fuse_conn_abort_write(). Setting fc->aborted is now racy (fuse_abort_conn() may already be in progress or finished) but there's no reason to care. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2019-02-13fuse: Add fuse_inode argument to fuse_prepare_release()Kirill Tkhai
Here is preparation for next patches, which introduce new fi->lock for protection of ff->write_entry linked into fi->write_files. This patch just passes new argument to the function. Signed-off-by: Kirill Tkhai <ktkhai@virtuozzo.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-03-20fuse: Support fuse filesystems outside of init_user_nsEric W. Biederman
In order to support mounts from namespaces other than init_user_ns, fuse must translate uids and gids to/from the userns of the process servicing requests on /dev/fuse. This patch does that, with a couple of restrictions on the namespace: - The userns for the fuse connection is fixed to the namespace from which /dev/fuse is opened. - The namespace must be the same as s_user_ns. These restrictions simplify the implementation by avoiding the need to pass around userns references and by allowing fuse to rely on the checks in setattr_prepare for ownership changes. Either restriction could be relaxed in the future if needed. For cuse the userns used is the opener of /dev/cuse. Semantically the cuse support does not appear safe for unprivileged users. Practically the permissions on /dev/cuse only make it accessible to the global root user. If something slips through the cracks in a user namespace the only users who will be able to use the cuse device are those users mapped into the user namespace. Translation in the posix acl is updated to use the uuser namespace of the filesystem. Avoiding cases which might bypass this translation is handled in a following change. This change is stronlgy based on a similar change from Seth Forshee and Dongsu Park. Cc: Seth Forshee <seth.forshee@canonical.com> Cc: Dongsu Park <dongsu@kinvolk.io> Signed-off-by: Eric W. Biederman <ebiederm@xmission.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2018-03-20fuse: return -ECONNABORTED on /dev/fuse read after abortSzymon Lukasz
Currently the userspace has no way of knowing whether the fuse connection ended because of umount or abort via sysfs. It makes it hard for filesystems to free the mountpoint after abort without worrying about removing some new mount. The patch fixes it by returning different errors when userspace reads from /dev/fuse (-ENODEV for umount and -ECONNABORTED for abort). Add a new capability flag FUSE_ABORT_ERROR. If set and the connection is gone because of sysfs abort, reading from the device will return -ECONNABORTED. Signed-off-by: Szymon Lukasz <noh4hss@gmail.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2017-09-12fuse: honor iocb sync flags on writeMiklos Szeredi
If the IOCB_DSYNC flag is set a sync is not being performed by fuse_file_write_iter. Honor IOCB_DSYNC/IOCB_SYNC by setting O_DYSNC/O_SYNC respectively in the flags filed of the write request. We don't need to sync data or metadata, since fuse_perform_write() does write-through and the filesystem is responsible for updating file times. Original patch by Vitaly Zolotusky. Reported-by: Nate Clark <nate@neworld.us> Cc: Vitaly Zolotusky <vitaly@unitc.com>. Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2016-03-14fuse: Add reference counting for fuse_io_privSeth Forshee
The 'reqs' member of fuse_io_priv serves two purposes. First is to track the number of oustanding async requests to the server and to signal that the io request is completed. The second is to be a reference count on the structure to know when it can be freed. For sync io requests these purposes can be at odds. fuse_direct_IO() wants to block until the request is done, and since the signal is sent when 'reqs' reaches 0 it cannot keep a reference to the object. Yet it needs to use the object after the userspace server has completed processing requests. This leads to some handshaking and special casing that it needlessly complicated and responsible for at least one race condition. It's much cleaner and safer to maintain a separate reference count for the object lifecycle and to let 'reqs' just be a count of outstanding requests to the userspace server. Then we can know for sure when it is safe to free the object without any handshaking or special cases. The catch here is that most of the time these objects are stack allocated and should not be freed. Initializing these objects with a single reference that is never released prevents accidental attempts to free the objects. Fixes: 9d5722b7777e ("fuse: handle synchronous iocbs internally") Cc: stable@vger.kernel.org # v4.1+ Signed-off-by: Seth Forshee <seth.forshee@canonical.com> Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
2015-11-10cuse: fix memory leakMiklos Szeredi
The problem is that fuse_dev_alloc() acquires an extra reference to cc.fc, and the original ref count is never dropped. Reported-by: Colin Ian King <colin.king@canonical.com> Signed-off-by: Miklos Szeredi <miklos@szeredi.hu> Fixes: cc080e9e9be1 ("fuse: introduce per-instance fuse_dev structure") Cc: <stable@vger.kernel.org> # v4.2+
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: 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>
2015-04-11make new_sync_{read,write}() staticAl Viro
All places outside of core VFS that checked ->read and ->write for being NULL or called the methods directly are gone now, so NULL {read,write} with non-NULL {read,write}_iter will do the right thing in all cases. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-04-11cuse: switch to iov_iterAl Viro
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2015-03-25fs: move struct kiocb to fs.hChristoph Hellwig
struct kiocb now is a generic I/O container, so move it to fs.h. Also do a #include diet for aio.h while we're at it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-12-12fuse: flush requests on umountMiklos Szeredi
Use fuse_abort_conn() instead of fuse_conn_kill() in fuse_put_super(). This flushes and aborts requests still on any queues. But since we've already reset fc->connected, those requests would not be useful anyway and would be flushed when the fuse device is closed. Next patches will rely on requests being flushed before the superblock is destroyed. Use fuse_abort_conn() in cuse_process_init_reply() too, since it makes no difference there, and we can get rid of fuse_conn_kill(). Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-05-06fuse: pull iov_iter initializations upAl Viro
... to fuse_direct_{read,write}(). ->direct_IO() path uses the iov_iter passed by the caller instead. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2014-04-06Merge tag 'modules-next-for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux Pull module updates from Rusty Russell: "Nothing major: the stricter permissions checking for sysfs broke a staging driver; fix included. Greg KH said he'd take the patch but hadn't as the merge window opened, so it's included here to avoid breaking build" * tag 'modules-next-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rusty/linux: staging: fix up speakup kobject mode Use 'E' instead of 'X' for unsigned module taint flag. VERIFY_OCTAL_PERMISSIONS: stricter checking for sysfs perms. kallsyms: fix percpu vars on x86-64 with relocation. kallsyms: generalize address range checking module: LLVMLinux: Remove unused function warning from __param_check macro Fix: module signature vs tracepoints: add new TAINT_UNSIGNED_MODULE module: remove MODULE_GENERIC_TABLE module: allow multiple calls to MODULE_DEVICE_TABLE() per module module: use pr_cont
2014-04-02fuse: Fix O_DIRECT operations vs cached writeback misorderPavel Emelyanov
The problem is: 1. write cached data to a file 2. read directly from the same file (via another fd) The 2nd operation may read stale data, i.e. the one that was in a file before the 1st op. Problem is in how fuse manages writeback. When direct op occurs the core kernel code calls filemap_write_and_wait to flush all the cached ops in flight. But fuse acks the writeback right after the ->writepages callback exits w/o waiting for the real write to happen. Thus the subsequent direct op proceeds while the real writeback is still in flight. This is a problem for backends that reorder operation. Fix this by making the fuse direct IO callback explicitly wait on the in-flight writeback to finish. Signed-off-by: Maxim Patlasov <MPatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2014-03-24VERIFY_OCTAL_PERMISSIONS: stricter checking for sysfs perms.Rusty Russell
Summary of http://lkml.org/lkml/2014/3/14/363 : Ted: module_param(queue_depth, int, 444) Joe: 0444! Rusty: User perms >= group perms >= other perms? Joe: CLASS_ATTR, DEVICE_ATTR, SENSOR_ATTR and SENSOR_ATTR_2? Side effect of stricter permissions means removing the unnecessary S_IFREG from several callers. Note that the BUILD_BUG_ON_ZERO((perm) & 2) test was removed: a fair number of drivers fail this test, so that will be the debate for a future patch. Suggested-by: Joe Perches <joe@perches.com> Acked-by: Bjorn Helgaas <bhelgaas@google.com> for drivers/pci/slot.c Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Miklos Szeredi <miklos@szeredi.hu> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
2013-11-13Merge branch 'for-linus' of ↵Linus Torvalds
git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs Pull vfs updates from Al Viro: "All kinds of stuff this time around; some more notable parts: - RCU'd vfsmounts handling - new primitives for coredump handling - files_lock is gone - Bruce's delegations handling series - exportfs fixes plus misc stuff all over the place" * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs: (101 commits) ecryptfs: ->f_op is never NULL locks: break delegations on any attribute modification locks: break delegations on link locks: break delegations on rename locks: helper functions for delegation breaking locks: break delegations on unlink namei: minor vfs_unlink cleanup locks: implement delegations locks: introduce new FL_DELEG lock flag vfs: take i_mutex on renamed file vfs: rename I_MUTEX_QUOTA now that it's not used for quotas vfs: don't use PARENT/CHILD lock classes for non-directories vfs: pull ext4's double-i_mutex-locking into common code exportfs: fix quadratic behavior in filehandle lookup exportfs: better variable name exportfs: move most of reconnect_path to helper function exportfs: eliminate unused "noprogress" counter exportfs: stop retrying once we race with rename/remove exportfs: clear DISCONNECTED on all parents sooner exportfs: more detailed comment for path_reconnect ...
2013-10-24fuse: rcu-delay freeing fuse_connAl Viro
makes ->permission() and ->d_revalidate() safety in RCU mode independent from vfsmount_lock. Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2013-10-01cuse: add fix minor number to /dev/cuseTom Gundersen
This allows udev (or more recently systemd-tmpfiles) to create /dev/cuse on boot, in the same way as /dev/fuse is currently created, and the corresponding module to be loaded on first access. The corresponding functionalty was introduced for fuse in commit 578454f. Signed-off-by: Tom Gundersen <teg@jklm.no> Cc: Kay Sievers <kay@vrfy.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-07-26cuse: convert class code to use dev_groupsGreg Kroah-Hartman
The dev_attrs field of struct class is going away soon, dev_groups should be used instead. This converts the cuse class code to use the correct field. Acked-by: Miklos Szeredi <mszeredi@suse.cz> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-05-07Merge branch 'akpm' (incoming from Andrew)Linus Torvalds
Merge more incoming from Andrew Morton: - Various fixes which were stalled or which I picked up recently - A large rotorooting of the AIO code. Allegedly to improve performance but I don't really have good performance numbers (I might have lost the email) and I can't raise Kent today. I held this out of 3.9 and we could give it another cycle if it's all too late/scary. I ended up taking only the first two thirds of the AIO rotorooting. I left the percpu parts and the batch completion for later. - Linus * emailed patches from Andrew Morton <akpm@linux-foundation.org>: (33 commits) aio: don't include aio.h in sched.h aio: kill ki_retry aio: kill ki_key aio: give shared kioctx fields their own cachelines aio: kill struct aio_ring_info aio: kill batch allocation aio: change reqs_active to include unreaped completions aio: use cancellation list lazily aio: use flush_dcache_page() aio: make aio_read_evt() more efficient, convert to hrtimers wait: add wait_event_hrtimeout() aio: refcounting cleanup aio: make aio_put_req() lockless aio: do fget() after aio_get_req() aio: dprintk() -> pr_debug() aio: move private stuff out of aio.h aio: add kiocb_cancel() aio: kill return value of aio_complete() char: add aio_{read,write} to /dev/{null,zero} aio: remove retry-based AIO ...
2013-05-07aio: don't include aio.h in sched.hKent Overstreet
Faster kernel compiles by way of fewer unnecessary includes. [akpm@linux-foundation.org: fix fallout] [akpm@linux-foundation.org: fix build] Signed-off-by: Kent Overstreet <koverstreet@google.com> Cc: Zach Brown <zab@redhat.com> Cc: Felipe Balbi <balbi@ti.com> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org> Cc: Mark Fasheh <mfasheh@suse.com> Cc: Joel Becker <jlbec@evilplan.org> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Jens Axboe <axboe@kernel.dk> Cc: Asai Thambi S P <asamymuthupa@micron.com> Cc: Selvan Mani <smani@micron.com> Cc: Sam Bradshaw <sbradshaw@micron.com> Cc: Jeff Moyer <jmoyer@redhat.com> Cc: Al Viro <viro@zeniv.linux.org.uk> Cc: Benjamin LaHaise <bcrl@kvack.org> Reviewed-by: "Theodore Ts'o" <tytso@mit.edu> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-04-17fuse: make fuse_direct_io() aware about AIOMaxim Patlasov
The patch implements passing "struct fuse_io_priv *io" down the stack up to fuse_send_read/write where it is used to submit request asynchronously. io->async==0 designates synchronous processing. Non-trivial part of the patch is changes in fuse_direct_io(): resources like fuse requests and user pages cannot be released immediately in async case. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17fuse: skip blocking on allocations of synchronous requestsMaxim Patlasov
A task may have at most one synchronous request allocated. So these requests need not be otherwise limited. The patch re-works fuse_get_req() to follow this idea. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17fuse: add flag fc->initializedMaxim Patlasov
Existing flag fc->blocked is used to suspend request allocation both in case of many background request submitted and period of time before init_reply arrives from userspace. Next patch will skip blocking allocations of synchronous request (disregarding fc->blocked). This is mostly OK, but we still need to suspend allocations if init_reply is not arrived yet. The patch introduces flag fc->initialized which will serve this purpose. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-04-17fuse: make request allocations for background processing explicitMaxim Patlasov
There are two types of processing requests in FUSE: synchronous (via fuse_request_send()) and asynchronous (via adding to fc->bg_queue). Fortunately, the type of processing is always known in advance, at the time of request allocation. This preparatory patch utilizes this fact making fuse_get_req() aware about the type. Next patches will use it. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24fuse: cleanup fuse_direct_io()Miklos Szeredi
Fix the following sparse warnings: fs/fuse/file.c:1216:43: warning: cast removes address space of expression fs/fuse/file.c:1216:43: warning: incorrect type in initializer (different address spaces) fs/fuse/file.c:1216:43: expected void [noderef] <asn:1>*iov_base fs/fuse/file.c:1216:43: got void *<noident> fs/fuse/file.c:1241:43: warning: cast removes address space of expression fs/fuse/file.c:1241:43: warning: incorrect type in initializer (different address spaces) fs/fuse/file.c:1241:43: expected void [noderef] <asn:1>*iov_base fs/fuse/file.c:1241:43: got void *<noident> fs/fuse/file.c:1267:43: warning: cast removes address space of expression fs/fuse/file.c:1267:43: warning: incorrect type in initializer (different address spaces) fs/fuse/file.c:1267:43: expected void [noderef] <asn:1>*iov_base fs/fuse/file.c:1267:43: got void *<noident> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24fuse: use req->page_descs[] for argpages casesMaxim Patlasov
Previously, anyone who set flag 'argpages' only filled req->pages[] and set per-request page_offset. This patch re-works all cases where argpages=1 to fill req->page_descs[] properly. Having req->page_descs[] filled properly allows to re-work fuse_copy_pages() to copy page fragments described by req->page_descs[]. This will be useful for next patches optimizing direct_IO. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-24fuse: categorize fuse_get_req()Maxim Patlasov
The patch categorizes all fuse_get_req() invocations into two categories: - fuse_get_req_nopages(fc) - when caller doesn't care about req->pages - fuse_get_req(fc, n) - when caller need n page pointers (n > 0) Adding fuse_get_req_nopages() helps to avoid numerous fuse_get_req(fc, 0) scattered over code. Now it's clear from the first glance when a caller need fuse_req with page pointers. The patch doesn't make any logic changes. In multi-page case, it silly allocates array of FUSE_MAX_PAGES_PER_REQ page pointers. This will be amended by future patches. Signed-off-by: Maxim Patlasov <mpatlasov@parallels.com> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17cuse: fix uninitialized variable warningsMiklos Szeredi
Fix the following compiler warnings: fs/fuse/cuse.c: In function 'cuse_process_init_reply': fs/fuse/cuse.c:288:24: warning: 'val' may be used uninitialized in this function [-Wmaybe-uninitialized] fs/fuse/cuse.c:272:14: note: 'val' was declared here fs/fuse/cuse.c:284:10: warning: 'key' may be used uninitialized in this function [-Wmaybe-uninitialized] fs/fuse/cuse.c:272:8: note: 'key' was declared here Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17cuse: do not register multiple devices with identical namesDavid Herrmann
Sysfs doesn't allow two devices with the same name, but we register a sysfs entry for each cuse device without checking for name collisions. This extends the registration to first check whether the name was already registered. To avoid race-conditions between the name-check and linking the device, we need to protect the whole registration with a mutex. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2013-01-17cuse: use mutex as registration lock instead of spinlocksDavid Herrmann
We need to check for name-collisions during cuse-device registration. To avoid race-conditions, this needs to be protected during the whole device registration. Therefore, replace the spinlocks by mutexes first so we can safely extend the locked regions to include more expensive or sleeping code paths. Signed-off-by: David Herrmann <dh.herrmann@googlemail.com> Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2012-08-30cuse: kill connection on initialization errorMiklos Szeredi
Luca Risolia reported that a CUSE daemon will continue to run even if initialization of the emulated device failes for some reason (e.g. the device number is already registered by another driver). This patch disconnects the fuse device on error, which will make the userspace CUSE daemon exit, albeit without indication about what the problem was. Reported-by: Luca Risolia <luca.risolia@studio.unibo.it> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-10-31fs: add module.h to files that were implicitly using itPaul Gortmaker
Some files were using the complete module.h infrastructure without actually including the header at all. Fix them up in advance so once the implicit presence is removed, we won't get failures like this: CC [M] fs/nfsd/nfssvc.o fs/nfsd/nfssvc.c: In function 'nfsd_create_serv': fs/nfsd/nfssvc.c:335: error: 'THIS_MODULE' undeclared (first use in this function) fs/nfsd/nfssvc.c:335: error: (Each undeclared identifier is reported only once fs/nfsd/nfssvc.c:335: error: for each function it appears in.) fs/nfsd/nfssvc.c: In function 'nfsd': fs/nfsd/nfssvc.c:555: error: implicit declaration of function 'module_put_and_exit' make[3]: *** [fs/nfsd/nfssvc.o] Error 1 Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
2011-03-22Merge branch 'for-linus' of ↵Linus Torvalds
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: make fuse_dentry_revalidate() RCU aware fuse: make fuse_permission() RCU aware fuse: wakeup pollers on connection release/abort fuse: reduce size of struct fuse_request
2011-03-21fuse: reduce size of struct fuse_requestMiklos Szeredi
Reduce the size of struct fuse_request by removing cuse_init_out from the request structure and allocating it dinamically instead. CC: Tejun Heo <tj@kernel.org> Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
2011-02-15fuse/cuse: fix comment typo initilaizationPaul Bolle
Signed-off-by: Paul Bolle <pebolle@tiscali.nl> Reviewed-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: Jiri Kosina <jkosina@suse.cz>
2010-10-15llseek: automatically add .llseek fopArnd Bergmann
All file_operations should get a .llseek operation so we can make nonseekable_open the default for future file operations without a .llseek pointer. The three cases that we can automatically detect are no_llseek, seq_lseek and default_llseek. For cases where we can we can automatically prove that the file offset is always ignored, we use noop_llseek, which maintains the current behavior of not returning an error from a seek. New drivers should normally not use noop_llseek but instead use no_llseek and call nonseekable_open at open time. Existing drivers can be converted to do the same when the maintainer knows for certain that no user code relies on calling seek on the device file. The generated code is often incorrectly indented and right now contains comments that clarify for each added line why a specific variant was chosen. In the version that gets submitted upstream, the comments will be gone and I will manually fix the indentation, because there does not seem to be a way to do that using coccinelle. Some amount of new code is currently sitting in linux-next that should get the same modifications, which I will do at the end of the merge window. Many thanks to Julia Lawall for helping me learn to write a semantic patch that does all this. ===== begin semantic patch ===== // This adds an llseek= method to all file operations, // as a preparation for making no_llseek the default. // // The rules are // - use no_llseek explicitly if we do nonseekable_open // - use seq_lseek for sequential files // - use default_llseek if we know we access f_pos // - use noop_llseek if we know we don't access f_pos, // but we still want to allow users to call lseek // @ open1 exists @ identifier nested_open; @@ nested_open(...) { <+... nonseekable_open(...) ...+> } @ open exists@ identifier open_f; identifier i, f; identifier open1.nested_open; @@ int open_f(struct inode *i, struct file *f) { <+... ( nonseekable_open(...) | nested_open(...) ) ...+> } @ read disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ read_no_fpos disable optional_qualifier exists @ identifier read_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t read_f(struct file *f, char *p, size_t s, loff_t *off) { ... when != off } @ write @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; expression E; identifier func; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { <+... ( *off = E | *off += E | func(..., off, ...) | E = *off ) ...+> } @ write_no_fpos @ identifier write_f; identifier f, p, s, off; type ssize_t, size_t, loff_t; @@ ssize_t write_f(struct file *f, const char *p, size_t s, loff_t *off) { ... when != off } @ fops0 @ identifier fops; @@ struct file_operations fops = { ... }; @ has_llseek depends on fops0 @ identifier fops0.fops; identifier llseek_f; @@ struct file_operations fops = { ... .llseek = llseek_f, ... }; @ has_read depends on fops0 @ identifier fops0.fops; identifier read_f; @@ struct file_operations fops = { ... .read = read_f, ... }; @ has_write depends on fops0 @ identifier fops0.fops; identifier write_f; @@ struct file_operations fops = { ... .write = write_f, ... }; @ has_open depends on fops0 @ identifier fops0.fops; identifier open_f; @@ struct file_operations fops = { ... .open = open_f, ... }; // use no_llseek if we call nonseekable_open //////////////////////////////////////////// @ nonseekable1 depends on !has_llseek && has_open @ identifier fops0.fops; identifier nso ~= "nonseekable_open"; @@ struct file_operations fops = { ... .open = nso, ... +.llseek = no_llseek, /* nonseekable */ }; @ nonseekable2 depends on !has_llseek @ identifier fops0.fops; identifier open.open_f; @@ struct file_operations fops = { ... .open = open_f, ... +.llseek = no_llseek, /* open uses nonseekable */ }; // use seq_lseek for sequential files ///////////////////////////////////// @ seq depends on !has_llseek @ identifier fops0.fops; identifier sr ~= "seq_read"; @@ struct file_operations fops = { ... .read = sr, ... +.llseek = seq_lseek, /* we have seq_read */ }; // use default_llseek if there is a readdir /////////////////////////////////////////// @ fops1 depends on !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier readdir_e; @@ // any other fop is used that changes pos struct file_operations fops = { ... .readdir = readdir_e, ... +.llseek = default_llseek, /* readdir is present */ }; // use default_llseek if at least one of read/write touches f_pos ///////////////////////////////////////////////////////////////// @ fops2 depends on !fops1 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read.read_f; @@ // read fops use offset struct file_operations fops = { ... .read = read_f, ... +.llseek = default_llseek, /* read accesses f_pos */ }; @ fops3 depends on !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, ... + .llseek = default_llseek, /* write accesses f_pos */ }; // Use noop_llseek if neither read nor write accesses f_pos /////////////////////////////////////////////////////////// @ fops4 depends on !fops1 && !fops2 && !fops3 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; identifier write_no_fpos.write_f; @@ // write fops use offset struct file_operations fops = { ... .write = write_f, .read = read_f, ... +.llseek = noop_llseek, /* read and write both use no f_pos */ }; @ depends on has_write && !has_read && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier write_no_fpos.write_f; @@ struct file_operations fops = { ... .write = write_f, ... +.llseek = noop_llseek, /* write uses no f_pos */ }; @ depends on has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; identifier read_no_fpos.read_f; @@ struct file_operations fops = { ... .read = read_f, ... +.llseek = noop_llseek, /* read uses no f_pos */ }; @ depends on !has_read && !has_write && !fops1 && !fops2 && !has_llseek && !nonseekable1 && !nonseekable2 && !seq @ identifier fops0.fops; @@ struct file_operations fops = { ... +.llseek = noop_llseek, /* no read or write fn */ }; ===== End semantic patch ===== Signed-off-by: Arnd Bergmann <arnd@arndb.de> Cc: Julia Lawall <julia@diku.dk> Cc: Christoph Hellwig <hch@infradead.org>
2010-03-30include cleanup: Update gfp.h and slab.h includes to prepare for breaking ↵Tejun Heo
implicit slab.h inclusion from percpu.h percpu.h is included by sched.h and module.h and thus ends up being included when building most .c files. percpu.h includes slab.h which in turn includes gfp.h making everything defined by the two files universally available and complicating inclusion dependencies. percpu.h -> slab.h dependency is about to be removed. Prepare for this change by updating users of gfp and slab facilities include those headers directly instead of assuming availability. As this conversion needs to touch large number of source files, the following script is used as the basis of conversion. http://userweb.kernel.org/~tj/misc/slabh-sweep.py The script does the followings. * Scan files for gfp and slab usages and update includes such that only the necessary includes are there. ie. if only gfp is used, gfp.h, if slab is used, slab.h. * When the script inserts a new include, it looks at the include blocks and try to put the new include such that its order conforms to its surrounding. It's put in the include block which contains core kernel includes, in the same order that the rest are ordered - alphabetical, Christmas tree, rev-Xmas-tree or at the end if there doesn't seem to be any matching order. * If the script can't find a place to put a new include (mostly because the file doesn't have fitting include block), it prints out an error message indicating which .h file needs to be added to the file. The conversion was done in the following steps. 1. The initial automatic conversion of all .c files updated slightly over 4000 files, deleting around 700 includes and adding ~480 gfp.h and ~3000 slab.h inclusions. The script emitted errors for ~400 files. 2. Each error was manually checked. Some didn't need the inclusion, some needed manual addition while adding it to implementation .h or embedding .c file was more appropriate for others. This step added inclusions to around 150 files. 3. The script was run again and the output was compared to the edits from #2 to make sure no file was left behind. 4. Several build tests were done and a couple of problems were fixed. e.g. lib/decompress_*.c used malloc/free() wrappers around slab APIs requiring slab.h to be added manually. 5. The script was run on all .h files but without automatically editing them as sprinkling gfp.h and slab.h inclusions around .h files could easily lead to inclusion dependency hell. Most gfp.h inclusion directives were ignored as stuff from gfp.h was usually wildly available and often used in preprocessor macros. Each slab.h inclusion directive was examined and added manually as necessary. 6. percpu.h was updated not to include slab.h. 7. Build test were done on the following configurations and failures were fixed. CONFIG_GCOV_KERNEL was turned off for all tests (as my distributed build env didn't work with gcov compiles) and a few more options had to be turned off depending on archs to make things build (like ipr on powerpc/64 which failed due to missing writeq). * x86 and x86_64 UP and SMP allmodconfig and a custom test config. * powerpc and powerpc64 SMP allmodconfig * sparc and sparc64 SMP allmodconfig * ia64 SMP allmodconfig * s390 SMP allmodconfig * alpha SMP allmodconfig * um on x86_64 SMP allmodconfig 8. percpu.h modifications were reverted so that it could be applied as a separate patch and serve as bisection point. Given the fact that I had only a couple of failures from tests on step 6, I'm fairly confident about the coverage of this conversion patch. If there is a breakage, it's likely to be something in one of the arch headers which should be easily discoverable easily on most builds of the specific arch. Signed-off-by: Tejun Heo <tj@kernel.org> Guess-its-ok-by: Christoph Lameter <cl@linux-foundation.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
2009-06-09CUSE: implement CUSE - Character device in UserspaceTejun Heo
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>