Change some "/**" to "/*" since they are not kernel-doc comments:
Warning: fs/fuse/fuse_dev_i.h:25 This comment starts with '/**', but isn't a kernel-doc comment. Refer to Documentation/doc-guide/kernel-doc.rst
* Request flags
Warning: fs/fuse/fuse_dev_i.h:58 This comment starts with '/**', but isn't a kernel-doc comment. Refer to Documentation/doc-guide/kernel-doc.rst
* A request to the client
Warning: fs/fuse/fuse_dev_i.h:117 This comment starts with '/**', but isn't a kernel-doc comment. Refer to Documentation/doc-guide/kernel-doc.rst
* Input queue callbacks
Warning: fs/fuse/fuse_dev_i.h:289 This comment starts with '/**', but isn't a kernel-doc comment. Refer to Documentation/doc-guide/kernel-doc.rst
* Fuse device instance
and more like this.
Convert enum fuse_req_flag to kernel-doc format.
Convert struct fuse_req, struct fuse_iqueue_ops, and struct fuse_dev
to kernel-doc format.
These warnings remain:
Warning: fs/fuse/fuse_dev_i.h:115 struct member 'ring_entry' not described in 'fuse_req'
Warning: fs/fuse/fuse_dev_i.h:115 struct member 'ring_queue' not described in 'fuse_req'
Binary build output is the same before and after these changes.
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Prior to this patchset, fuse_dev (containing fuse_pqueue) was allocated on
mount. But now fuse_dev is allocated when opening /dev/fuse, even though
the queues are not needed at that time.
Delay allocation of the pqueue (4k worth of list_head) just before mounting
or cloning a device.
Various distributions (e.g. Debian/Fedora) configure /dev/fuse as world
writable, so the pqueue allocation should be deferred to a privileged
operation (mount) to prevent unprivileged userspace from consuming pinned
kernel memory.
[Li Wang: fix kernel NULL pointer dereference in fuse_uring_add_to_pq()]
[Fix race in fuse_dev_release()]
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Move a couple of function declarations from fuse_i.h to dev.h and
fuse_dev_i.h.
Add fuse_conn_get_id() helper that retrieves the connection ID (s_dev) from
fuse_conn.
With the exception of cuse.c, virtio_fs.c and trace.c source files now
either include fuse_i.h or fuse_dev_i/dev_uring_i.h but not both.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Set minor, max_write and max_pages in the fuse_chan. These match the same
fields in fuse_conn but are needed in both layers.
[Dongyang Jin: Pointers should use NULL instead of explicit '0']
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
- rename fuse_abort_conn() to fuse_chan_abort(), pass fuse_chan pointer
instead of fuse_conn
- pass an abort_with_err argument that tells fuse_dev_(read|write) to
return with ECONNABORTED instead of ENODEV
- move fc->aborted to fch->abort_with_err
- rename fuse_wait_aborted() to fuse_chan_wait_aborted()
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
And document which members they protect.
end_polls() is called with both, outer fch->lock is probably unnecessary,
but doesn't hurt for now.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Move the 'fiq' member from fuse_conn to fuse_chan.
Move iqueue related structure definitions and function declarations from
"fuse_i.h" to "fuse_dev_i.h".
Add a fuse_dev_chan_new() helper, that returns a fuse_chan initialized with
the fuse_dev_fiq_ops.
Add a fuse_chan_release() function, that calls fiq->ops->release().
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
The goal is to separate transport layer stuff out from struct fuse_conn,
leaving just the filesystem related members.
Add a new object referenced from fuse_conn. This patch just implements the
allocation and freeing of this object.
Following patches will move transport related members from fuse_conn to
fuse_chan.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
When a background request completes via the io_uring path, the
background queue gets flushed to dispatch pending background requests,
but this is done before the connection-level background counters
(fc->num_background, fc->active_background) are properly accounted,
which may reduce effective queue depth to one.
The connection-level counters are decremented in fuse_request_end(), but
flush_bg_queue() flushes the /dev/fuse path queue (fc->bg_queue), not
the io_uring per-queue bg one, which means pending uring background
requests on the queue are never dispatched in this path.
Fix this by accounting the connection-level background counters first
before flushing the queue's background queue. Since
fuse_request_bg_finish() clears FR_BACKGROUND, fuse_request_end() will
skip the background cleanup branch entirely, which avoids any
double-decrements; it will call the wake_up(&req->waitq) branch but this
is effectively a no-op as background requests have no waiters on
req->waitq.
Reviewed-by: Bernd Schubert <bernd@bsbernd.com>
Fixes: 857b0263f3 ("fuse: Allow to queue bg requests through io-uring")
Cc: stable@vger.kernel.org
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This will make it possible to grab the fuse_dev and subsequently release
the file that it came from.
In the above case, fud->fc will be set to FUSE_DEV_FC_DISCONNECTED to
indicate that this is no longer a functional device.
When trying to assign an fc to such a disconnected fuse_dev, the fc is set
to the disconnected state.
Use atomic operations xchg() and cmpxchg() to prevent races.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Allocate struct fuse_dev when opening the device. This means that unlike
before, ->private_data is always set to a valid pointer.
The use of USE_DEV_SYNC_INIT magic pointer for the private_data is now
replaced with a simple bool sync_init member.
If sync INIT is not set, I/O on the device returns error before mount.
Keep this behavior by checking for the ->fc member. If fud->fc is set, the
mount has succeeded. Testing this used READ_ONCE(file->private_data) and
smp_mb() to try and provide the necessary semantics. Switch this to
smp_store_release() and smp_load_acquire().
Setting fud->fc is protected by fuse_mutex, this is unchanged.
Will need this later so the /dev/fuse open file reference is not held
during FSCONFIG_CMD_CREATE.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Reviewed-by: "Darrick J. Wong" <djwong@kernel.org>
FUSE_INIT has always been asynchronous with mount. That means that the
server processed this request after the mount syscall returned.
This means that FUSE_INIT can't supply the root inode's ID, hence it
currently has a hardcoded value. There are other limitations such as not
being able to perform getxattr during mount, which is needed by selinux.
To remove these limitations allow server to process FUSE_INIT while
initializing the in-core super block for the fuse filesystem. This can
only be done if the server is prepared to handle this, so add
FUSE_DEV_IOC_SYNC_INIT ioctl, which
a) lets the server know whether this feature is supported, returning
ENOTTY othewrwise.
b) lets the kernel know to perform a synchronous initialization
The implementation is slightly tricky, since fuse_dev/fuse_conn are set up
only during super block creation. This is solved by setting the private
data of the fuse device file to a special value ((struct fuse_dev *) 1) and
waiting for this to be turned into a proper fuse_dev before commecing with
operations on the device file.
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Currently, all folios associated with fuse are one page size. As part of
the work to enable large folios, this commit adds support for copying
to/from folios larger than one page size.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Reviewed-by: Bernd Schubert <bschubert@ddn.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Currently, when checking whether a request has timed out, we check
fpq processing, but fuse-over-io-uring has one fpq per core and 256
entries in the processing table. For systems where there are a
large number of cores, this may be too much overhead.
Instead of checking the fpq processing list, check ent_w_req_queue
and ent_in_userspace.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Bernd Schubert <bernd@bsbernd.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Refactor struct fuse_copy_state to use boolean bit-fields to improve
clarity/readability and be consistent with other fuse structs that use
bit-fields for boolean state (eg fuse_fs_context, fuse_args).
No functional changes.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Use a bitfield for 'write' in struct fuse_copy_state.
No functional changes.
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
There are situations where fuse servers can become unresponsive or
stuck, for example if the server is deadlocked. Currently, there's no
good way to detect if a server is stuck and needs to be killed manually.
This commit adds an option for enforcing a timeout (in seconds) for
requests where if the timeout elapses without the server responding to
the request, the connection will be automatically aborted.
Please note that these timeouts are not 100% precise. For example, the
request may take roughly an extra FUSE_TIMEOUT_TIMER_FREQ seconds beyond
the requested timeout due to internal implementation, in order to
mitigate overhead.
[SzM: Bump the API version number]
Signed-off-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
task-A (application) might be in request_wait_answer and
try to remove the request when it has FR_PENDING set.
task-B (a fuse-server io-uring task) might handle this
request with FUSE_IO_URING_CMD_COMMIT_AND_FETCH, when
fetching the next request and accessed the req from
the pending list in fuse_uring_ent_assign_req().
That code path was not protected by fiq->lock and so
might race with task-A.
For scaling reasons we better don't use fiq->lock, but
add a handler to remove canceled requests from the queue.
This also removes usage of fiq->lock from
fuse_uring_add_req_to_ring_ent() altogether, as it was
there just to protect against this race and incomplete.
Also added is a comment why FR_PENDING is not cleared.
Fixes: c090c8abae ("fuse: Add io-uring sqe commit and fetch support")
Cc: <stable@vger.kernel.org> # v6.14
Reported-by: Joanne Koong <joannelkoong@gmail.com>
Closes: https://lore.kernel.org/all/CAJnrk1ZgHNb78dz-yfNTpxmW7wtT88A=m-zF0ZoLXKLUHRjNTw@mail.gmail.com/
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Joanne Koong <joannelkoong@gmail.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
These functions are also needed by fuse-over-io-uring.
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Luis Henriques <luis@igalia.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
fuse-over-io-uring uses existing functions to find requests based
on their unique id - make these functions non-static.
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Luis Henriques <luis@igalia.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Move 'struct fuse_copy_state' and fuse_copy_* functions
to fuse_dev_i.h to make it available for fuse-io-uring.
'copy_out_args()' is renamed to 'fuse_copy_out_args'.
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Luis Henriques <luis@igalia.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
These are needed by fuse-over-io-uring.
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Luis Henriques <luis@igalia.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
Another preparation patch, as this function will be needed by
fuse/dev.c and fuse/dev_uring.c.
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Luis Henriques <luis@igalia.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
This function is needed by fuse_uring.c to clean ring queues,
so make it non static. Especially in non-static mode the function
name 'end_requests' should be prefixed with fuse_
Signed-off-by: Bernd Schubert <bschubert@ddn.com>
Reviewed-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: Joanne Koong <joannelkoong@gmail.com>
Reviewed-by: Luis Henriques <luis@igalia.com>
Signed-off-by: Miklos Szeredi <mszeredi@redhat.com>
