On 11/27/24 13:40, Bernd Schubert wrote:
This prepares queueing and sending foreground requests through
io-uring.
Signed-off-by: Bernd Schubert <bschubert@xxxxxxx>
---
fs/fuse/dev.c | 5 +-
fs/fuse/dev_uring.c | 159 ++++++++++++++++++++++++++++++++++++++++++++++++++
fs/fuse/dev_uring_i.h | 8 +++
fs/fuse/fuse_dev_i.h | 5 ++
4 files changed, 175 insertions(+), 2 deletions(-)
...
+
+/*
+ * This prepares and sends the ring request in fuse-uring task context.
+ * User buffers are not mapped yet - the application does not have permission
+ * to write to it - this has to be executed in ring task context.
+ */
+static void
+fuse_uring_send_req_in_task(struct io_uring_cmd *cmd,
+ unsigned int issue_flags)
+{
+ struct fuse_uring_cmd_pdu *pdu = (struct fuse_uring_cmd_pdu *)cmd->pdu;
+ struct fuse_ring_ent *ring_ent = pdu->ring_ent;
+ struct fuse_ring_queue *queue = ring_ent->queue;
+ int err;
+
+ BUILD_BUG_ON(sizeof(pdu) > sizeof(cmd->pdu));
+
+ err = fuse_uring_prepare_send(ring_ent);
+ if (err)
+ goto err;
+
+ io_uring_cmd_done(cmd, 0, 0, issue_flags);
+
+ spin_lock(&queue->lock);
+ ring_ent->state = FRRS_USERSPACE;
I haven't followed the cancellation/teardown path well, but don't
you need to set FRRS_USERSPACE before io_uring_cmd_done()?
E.g. while we're just before the spin_lock above here, can
fuse_uring_stop_list_entries() find the request, see that the state
is not FRRS_USERSPACE
bool need_cmd_done = ent->state != FRRS_USERSPACE;
and call io_uring_cmd_done a second time?
--
Pavel Begunkov
