return enable_uring;
}
+static void fuse_uring_req_end(struct fuse_ring_ent *ent, struct fuse_req *req,
+ int error)
+{
+ ent->fuse_req = NULL;
+ if (error)
+ req->out.h.error = error;
+
+ clear_bit(FR_SENT, &req->flags);
+ fuse_request_end(req);
+}
+
void fuse_uring_destruct(struct fuse_conn *fc)
{
struct fuse_ring *ring = fc->ring;
continue;
WARN_ON(!list_empty(&queue->ent_avail_queue));
+ WARN_ON(!list_empty(&queue->ent_w_req_queue));
WARN_ON(!list_empty(&queue->ent_commit_queue));
+ WARN_ON(!list_empty(&queue->ent_in_userspace));
+ kfree(queue->fpq.processing);
kfree(queue);
ring->queues[qid] = NULL;
}
{
struct fuse_conn *fc = ring->fc;
struct fuse_ring_queue *queue;
+ struct list_head *pq;
queue = kzalloc(sizeof(*queue), GFP_KERNEL_ACCOUNT);
if (!queue)
return NULL;
+ pq = kcalloc(FUSE_PQ_HASH_SIZE, sizeof(struct list_head), GFP_KERNEL);
+ if (!pq) {
+ kfree(queue);
+ return NULL;
+ }
+
queue->qid = qid;
queue->ring = ring;
spin_lock_init(&queue->lock);
INIT_LIST_HEAD(&queue->ent_avail_queue);
INIT_LIST_HEAD(&queue->ent_commit_queue);
+ INIT_LIST_HEAD(&queue->ent_w_req_queue);
+ INIT_LIST_HEAD(&queue->ent_in_userspace);
+ INIT_LIST_HEAD(&queue->fuse_req_queue);
+
+ queue->fpq.processing = pq;
+ fuse_pqueue_init(&queue->fpq);
spin_lock(&fc->lock);
if (ring->queues[qid]) {
spin_unlock(&fc->lock);
+ kfree(queue->fpq.processing);
kfree(queue);
return ring->queues[qid];
}
return queue;
}
+/*
+ * Checks for errors and stores it into the request
+ */
+static int fuse_uring_out_header_has_err(struct fuse_out_header *oh,
+ struct fuse_req *req,
+ struct fuse_conn *fc)
+{
+ int err;
+
+ err = -EINVAL;
+ if (oh->unique == 0) {
+ /* Not supported through io-uring yet */
+ pr_warn_once("notify through fuse-io-uring not supported\n");
+ goto err;
+ }
+
+ if (oh->error <= -ERESTARTSYS || oh->error > 0)
+ goto err;
+
+ if (oh->error) {
+ err = oh->error;
+ goto err;
+ }
+
+ err = -ENOENT;
+ if ((oh->unique & ~FUSE_INT_REQ_BIT) != req->in.h.unique) {
+ pr_warn_ratelimited("unique mismatch, expected: %llu got %llu\n",
+ req->in.h.unique,
+ oh->unique & ~FUSE_INT_REQ_BIT);
+ goto err;
+ }
+
+ /*
+ * Is it an interrupt reply ID?
+ * XXX: Not supported through fuse-io-uring yet, it should not even
+ * find the request - should not happen.
+ */
+ WARN_ON_ONCE(oh->unique & FUSE_INT_REQ_BIT);
+
+ err = 0;
+err:
+ return err;
+}
+
+static int fuse_uring_copy_from_ring(struct fuse_ring *ring,
+ struct fuse_req *req,
+ struct fuse_ring_ent *ent)
+{
+ struct fuse_copy_state cs;
+ struct fuse_args *args = req->args;
+ struct iov_iter iter;
+ int err;
+ struct fuse_uring_ent_in_out ring_in_out;
+
+ err = copy_from_user(&ring_in_out, &ent->headers->ring_ent_in_out,
+ sizeof(ring_in_out));
+ if (err)
+ return -EFAULT;
+
+ err = import_ubuf(ITER_SOURCE, ent->payload, ring->max_payload_sz,
+ &iter);
+ if (err)
+ return err;
+
+ fuse_copy_init(&cs, 0, &iter);
+ cs.is_uring = 1;
+ cs.req = req;
+
+ return fuse_copy_out_args(&cs, args, ring_in_out.payload_sz);
+}
+
+ /*
+ * Copy data from the req to the ring buffer
+ */
+static int fuse_uring_args_to_ring(struct fuse_ring *ring, struct fuse_req *req,
+ struct fuse_ring_ent *ent)
+{
+ struct fuse_copy_state cs;
+ struct fuse_args *args = req->args;
+ struct fuse_in_arg *in_args = args->in_args;
+ int num_args = args->in_numargs;
+ int err;
+ struct iov_iter iter;
+ struct fuse_uring_ent_in_out ent_in_out = {
+ .flags = 0,
+ .commit_id = req->in.h.unique,
+ };
+
+ err = import_ubuf(ITER_DEST, ent->payload, ring->max_payload_sz, &iter);
+ if (err) {
+ pr_info_ratelimited("fuse: Import of user buffer failed\n");
+ return err;
+ }
+
+ fuse_copy_init(&cs, 1, &iter);
+ cs.is_uring = 1;
+ cs.req = req;
+
+ if (num_args > 0) {
+ /*
+ * Expectation is that the first argument is the per op header.
+ * Some op code have that as zero size.
+ */
+ if (args->in_args[0].size > 0) {
+ err = copy_to_user(&ent->headers->op_in, in_args->value,
+ in_args->size);
+ if (err) {
+ pr_info_ratelimited(
+ "Copying the header failed.\n");
+ return -EFAULT;
+ }
+ }
+ in_args++;
+ num_args--;
+ }
+
+ /* copy the payload */
+ err = fuse_copy_args(&cs, num_args, args->in_pages,
+ (struct fuse_arg *)in_args, 0);
+ if (err) {
+ pr_info_ratelimited("%s fuse_copy_args failed\n", __func__);
+ return err;
+ }
+
+ ent_in_out.payload_sz = cs.ring.copied_sz;
+ err = copy_to_user(&ent->headers->ring_ent_in_out, &ent_in_out,
+ sizeof(ent_in_out));
+ return err ? -EFAULT : 0;
+}
+
+static int fuse_uring_copy_to_ring(struct fuse_ring_ent *ent,
+ struct fuse_req *req)
+{
+ struct fuse_ring_queue *queue = ent->queue;
+ struct fuse_ring *ring = queue->ring;
+ int err;
+
+ err = -EIO;
+ if (WARN_ON(ent->state != FRRS_FUSE_REQ)) {
+ pr_err("qid=%d ring-req=%p invalid state %d on send\n",
+ queue->qid, ent, ent->state);
+ return err;
+ }
+
+ err = -EINVAL;
+ if (WARN_ON(req->in.h.unique == 0))
+ return err;
+
+ /* copy the request */
+ err = fuse_uring_args_to_ring(ring, req, ent);
+ if (unlikely(err)) {
+ pr_info_ratelimited("Copy to ring failed: %d\n", err);
+ return err;
+ }
+
+ /* copy fuse_in_header */
+ err = copy_to_user(&ent->headers->in_out, &req->in.h,
+ sizeof(req->in.h));
+ if (err) {
+ err = -EFAULT;
+ return err;
+ }
+
+ return 0;
+}
+
+static int fuse_uring_prepare_send(struct fuse_ring_ent *ent,
+ struct fuse_req *req)
+{
+ int err;
+
+ err = fuse_uring_copy_to_ring(ent, req);
+ if (!err)
+ set_bit(FR_SENT, &req->flags);
+ else
+ fuse_uring_req_end(ent, req, err);
+
+ return err;
+}
+
+/*
+ * Write data to the ring buffer and send the request to userspace,
+ * userspace will read it
+ * This is comparable with classical read(/dev/fuse)
+ */
+static int fuse_uring_send_next_to_ring(struct fuse_ring_ent *ent,
+ struct fuse_req *req,
+ unsigned int issue_flags)
+{
+ struct fuse_ring_queue *queue = ent->queue;
+ int err;
+ struct io_uring_cmd *cmd;
+
+ err = fuse_uring_prepare_send(ent, req);
+ if (err)
+ return err;
+
+ spin_lock(&queue->lock);
+ cmd = ent->cmd;
+ ent->cmd = NULL;
+ ent->state = FRRS_USERSPACE;
+ list_move(&ent->list, &queue->ent_in_userspace);
+ spin_unlock(&queue->lock);
+
+ io_uring_cmd_done(cmd, 0, 0, issue_flags);
+ return 0;
+}
+
/*
* Make a ring entry available for fuse_req assignment
*/
ent->state = FRRS_AVAILABLE;
}
+/* Used to find the request on SQE commit */
+static void fuse_uring_add_to_pq(struct fuse_ring_ent *ent,
+ struct fuse_req *req)
+{
+ struct fuse_ring_queue *queue = ent->queue;
+ struct fuse_pqueue *fpq = &queue->fpq;
+ unsigned int hash;
+
+ req->ring_entry = ent;
+ hash = fuse_req_hash(req->in.h.unique);
+ list_move_tail(&req->list, &fpq->processing[hash]);
+}
+
+/*
+ * Assign a fuse queue entry to the given entry
+ */
+static void fuse_uring_add_req_to_ring_ent(struct fuse_ring_ent *ent,
+ struct fuse_req *req)
+{
+ struct fuse_ring_queue *queue = ent->queue;
+ struct fuse_conn *fc = req->fm->fc;
+ struct fuse_iqueue *fiq = &fc->iq;
+
+ lockdep_assert_held(&queue->lock);
+
+ if (WARN_ON_ONCE(ent->state != FRRS_AVAILABLE &&
+ ent->state != FRRS_COMMIT)) {
+ pr_warn("%s qid=%d state=%d\n", __func__, ent->queue->qid,
+ ent->state);
+ }
+
+ spin_lock(&fiq->lock);
+ clear_bit(FR_PENDING, &req->flags);
+ spin_unlock(&fiq->lock);
+ ent->fuse_req = req;
+ ent->state = FRRS_FUSE_REQ;
+ list_move(&ent->list, &queue->ent_w_req_queue);
+ fuse_uring_add_to_pq(ent, req);
+}
+
+/* Fetch the next fuse request if available */
+static struct fuse_req *fuse_uring_ent_assign_req(struct fuse_ring_ent *ent)
+ __must_hold(&queue->lock)
+{
+ struct fuse_req *req;
+ struct fuse_ring_queue *queue = ent->queue;
+ struct list_head *req_queue = &queue->fuse_req_queue;
+
+ lockdep_assert_held(&queue->lock);
+
+ /* get and assign the next entry while it is still holding the lock */
+ req = list_first_entry_or_null(req_queue, struct fuse_req, list);
+ if (req)
+ fuse_uring_add_req_to_ring_ent(ent, req);
+
+ return req;
+}
+
+/*
+ * Read data from the ring buffer, which user space has written to
+ * This is comparible with handling of classical write(/dev/fuse).
+ * Also make the ring request available again for new fuse requests.
+ */
+static void fuse_uring_commit(struct fuse_ring_ent *ent, struct fuse_req *req,
+ unsigned int issue_flags)
+{
+ struct fuse_ring *ring = ent->queue->ring;
+ struct fuse_conn *fc = ring->fc;
+ ssize_t err = 0;
+
+ err = copy_from_user(&req->out.h, &ent->headers->in_out,
+ sizeof(req->out.h));
+ if (err) {
+ req->out.h.error = -EFAULT;
+ goto out;
+ }
+
+ err = fuse_uring_out_header_has_err(&req->out.h, req, fc);
+ if (err) {
+ /* req->out.h.error already set */
+ goto out;
+ }
+
+ err = fuse_uring_copy_from_ring(ring, req, ent);
+out:
+ fuse_uring_req_end(ent, req, err);
+}
+
+/*
+ * Get the next fuse req and send it
+ */
+static void fuse_uring_next_fuse_req(struct fuse_ring_ent *ent,
+ struct fuse_ring_queue *queue,
+ unsigned int issue_flags)
+{
+ int err;
+ struct fuse_req *req;
+
+retry:
+ spin_lock(&queue->lock);
+ fuse_uring_ent_avail(ent, queue);
+ req = fuse_uring_ent_assign_req(ent);
+ spin_unlock(&queue->lock);
+
+ if (req) {
+ err = fuse_uring_send_next_to_ring(ent, req, issue_flags);
+ if (err)
+ goto retry;
+ }
+}
+
+static int fuse_ring_ent_set_commit(struct fuse_ring_ent *ent)
+{
+ struct fuse_ring_queue *queue = ent->queue;
+
+ lockdep_assert_held(&queue->lock);
+
+ if (WARN_ON_ONCE(ent->state != FRRS_USERSPACE))
+ return -EIO;
+
+ ent->state = FRRS_COMMIT;
+ list_move(&ent->list, &queue->ent_commit_queue);
+
+ return 0;
+}
+
+/* FUSE_URING_CMD_COMMIT_AND_FETCH handler */
+static int fuse_uring_commit_fetch(struct io_uring_cmd *cmd, int issue_flags,
+ struct fuse_conn *fc)
+{
+ const struct fuse_uring_cmd_req *cmd_req = io_uring_sqe_cmd(cmd->sqe);
+ struct fuse_ring_ent *ent;
+ int err;
+ struct fuse_ring *ring = fc->ring;
+ struct fuse_ring_queue *queue;
+ uint64_t commit_id = READ_ONCE(cmd_req->commit_id);
+ unsigned int qid = READ_ONCE(cmd_req->qid);
+ struct fuse_pqueue *fpq;
+ struct fuse_req *req;
+
+ err = -ENOTCONN;
+ if (!ring)
+ return err;
+
+ if (qid >= ring->nr_queues)
+ return -EINVAL;
+
+ queue = ring->queues[qid];
+ if (!queue)
+ return err;
+ fpq = &queue->fpq;
+
+ spin_lock(&queue->lock);
+ /* Find a request based on the unique ID of the fuse request
+ * This should get revised, as it needs a hash calculation and list
+ * search. And full struct fuse_pqueue is needed (memory overhead).
+ * As well as the link from req to ring_ent.
+ */
+ req = fuse_request_find(fpq, commit_id);
+ err = -ENOENT;
+ if (!req) {
+ pr_info("qid=%d commit_id %llu not found\n", queue->qid,
+ commit_id);
+ spin_unlock(&queue->lock);
+ return err;
+ }
+ list_del_init(&req->list);
+ ent = req->ring_entry;
+ req->ring_entry = NULL;
+
+ err = fuse_ring_ent_set_commit(ent);
+ if (err != 0) {
+ pr_info_ratelimited("qid=%d commit_id %llu state %d",
+ queue->qid, commit_id, ent->state);
+ spin_unlock(&queue->lock);
+ req->out.h.error = err;
+ clear_bit(FR_SENT, &req->flags);
+ fuse_request_end(req);
+ return err;
+ }
+
+ ent->cmd = cmd;
+ spin_unlock(&queue->lock);
+
+ /* without the queue lock, as other locks are taken */
+ fuse_uring_commit(ent, req, issue_flags);
+
+ /*
+ * Fetching the next request is absolutely required as queued
+ * fuse requests would otherwise not get processed - committing
+ * and fetching is done in one step vs legacy fuse, which has separated
+ * read (fetch request) and write (commit result).
+ */
+ fuse_uring_next_fuse_req(ent, queue, issue_flags);
+ return 0;
+}
+
/*
* fuse_uring_req_fetch command handling
*/
return err;
}
break;
+ case FUSE_IO_URING_CMD_COMMIT_AND_FETCH:
+ err = fuse_uring_commit_fetch(cmd, issue_flags, fc);
+ if (err) {
+ pr_info_once("FUSE_IO_URING_COMMIT_AND_FETCH failed err=%d\n",
+ err);
+ return err;
+ }
+ break;
default:
return -EINVAL;
}
projects / users / willy / pagecache.git / commitdiff