kernel.git/fs/fuse/fuse_dev_i.h, branch linux-6.15.y

fuse: add kernel-enforced timeout option for requests

2025-03-31T12:59:25Z

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 Reviewed-by: Jeff Layton Signed-off-by: Miklos Szeredi

fuse: {io-uring} Fix a possible req cancellation race

2025-03-31T12:53:02Z

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: c090c8abae4b ("fuse: Add io-uring sqe commit and fetch support") Cc: # v6.14 Reported-by: Joanne Koong Closes: https://lore.kernel.org/all/CAJnrk1ZgHNb78dz-yfNTpxmW7wtT88A=m-zF0ZoLXKLUHRjNTw@mail.gmail.com/ Signed-off-by: Bernd Schubert Reviewed-by: Joanne Koong Signed-off-by: Miklos Szeredi

fuse: {io-uring} Make fuse_dev_queue_{interrupt,forget} non-static

2025-01-27T17:01:22Z

These functions are also needed by fuse-over-io-uring. Signed-off-by: Bernd Schubert Reviewed-by: Luis Henriques Signed-off-by: Miklos Szeredi

fuse: {io-uring} Make hash-list req unique finding functions non-static

2025-01-24T10:54:20Z

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 Reviewed-by: Joanne Koong Reviewed-by: Luis Henriques Signed-off-by: Miklos Szeredi

fuse: Add fuse-io-uring handling into fuse_copy

2025-01-24T10:54:16Z

Add special fuse-io-uring into the fuse argument copy handler. Signed-off-by: Bernd Schubert Reviewed-by: Joanne Koong Reviewed-by: Luis Henriques Signed-off-by: Miklos Szeredi

fuse: Make fuse_copy non static

2025-01-24T10:54:12Z

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 Reviewed-by: Joanne Koong Reviewed-by: Luis Henriques Signed-off-by: Miklos Szeredi

fuse: Move request bits

2025-01-24T10:53:51Z

These are needed by fuse-over-io-uring. Signed-off-by: Bernd Schubert Reviewed-by: Josef Bacik Reviewed-by: Joanne Koong Reviewed-by: Luis Henriques Signed-off-by: Miklos Szeredi

fuse: Move fuse_get_dev to header file

2025-01-24T10:53:45Z

Another preparation patch, as this function will be needed by fuse/dev.c and fuse/dev_uring.c. Signed-off-by: Bernd Schubert Reviewed-by: Josef Bacik Reviewed-by: Joanne Koong Reviewed-by: Luis Henriques Signed-off-by: Miklos Szeredi

fuse: rename to fuse_dev_end_requests and make non-static

2025-01-24T10:53:25Z

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 Reviewed-by: Josef Bacik Reviewed-by: Joanne Koong Reviewed-by: Luis Henriques Signed-off-by: Miklos Szeredi