| Message ID | 20240529-fuse-uring-for-6-9-rfc2-out-v1-12-d149476b1d65@ddn.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | fuse: fuse-over-io-uring | expand |
On Wed, May 29, 2024 at 08:00:47PM +0200, Bernd Schubert wrote: > This adds support for fuse request completion through ring SQEs > (FUSE_URING_REQ_COMMIT_AND_FETCH handling). After committing > the ring entry it becomes available for new fuse requests. > Handling of requests through the ring (SQE/CQE handling) > is complete now. > > Fuse request data are copied through the mmaped ring buffer, > there is no support for any zero copy yet. > > Signed-off-by: Bernd Schubert <bschubert@ddn.com> > --- > fs/fuse/dev_uring.c | 311 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 311 insertions(+) > > diff --git a/fs/fuse/dev_uring.c b/fs/fuse/dev_uring.c > index 48b1118b64f4..5269b3f8891e 100644 > --- a/fs/fuse/dev_uring.c > +++ b/fs/fuse/dev_uring.c > @@ -31,12 +31,23 @@ > #include <linux/topology.h> > #include <linux/io_uring/cmd.h> > > +static void fuse_uring_req_end_and_get_next(struct fuse_ring_ent *ring_ent, > + bool set_err, int error, > + unsigned int issue_flags); > + Just order this above all the users instead of putting a declaration here. > static void fuse_ring_ring_ent_unset_userspace(struct fuse_ring_ent *ent) > { > clear_bit(FRRS_USERSPACE, &ent->state); > list_del_init(&ent->list); > } > > +static void > +fuse_uring_async_send_to_ring(struct io_uring_cmd *cmd, > + unsigned int issue_flags) > +{ > + io_uring_cmd_done(cmd, 0, 0, issue_flags); > +} > + > /* Update conn limits according to ring values */ > static void fuse_uring_conn_cfg_limits(struct fuse_ring *ring) > { > @@ -350,6 +361,188 @@ int fuse_uring_queue_cfg(struct fuse_ring *ring, > return 0; > } > > +/* > + * Checks for errors and stores it into the request > + */ > +static int fuse_uring_ring_ent_has_err(struct fuse_ring *ring, > + struct fuse_ring_ent *ring_ent) > +{ > + struct fuse_conn *fc = ring->fc; > + struct fuse_req *req = ring_ent->fuse_req; > + struct fuse_out_header *oh = &req->out.h; > + int err; > + > + if (oh->unique == 0) { > + /* Not supportd through request based uring, this needs another > + * ring from user space to kernel > + */ > + pr_warn("Unsupported fuse-notify\n"); > + err = -EINVAL; > + goto seterr; > + } > + > + if (oh->error <= -512 || oh->error > 0) { What is -512? No magic numbers please. > + err = -EINVAL; > + goto seterr; > + } > + > + if (oh->error) { > + err = oh->error; > + pr_devel("%s:%d err=%d op=%d req-ret=%d", __func__, __LINE__, > + err, req->args->opcode, req->out.h.error); > + goto err; /* error already set */ > + } > + > + if ((oh->unique & ~FUSE_INT_REQ_BIT) != req->in.h.unique) { > + pr_warn("Unpexted seqno mismatch, expected: %llu got %llu\n", > + req->in.h.unique, oh->unique & ~FUSE_INT_REQ_BIT); > + err = -ENOENT; > + goto seterr; > + } > + > + /* Is it an interrupt reply ID? */ > + if (oh->unique & FUSE_INT_REQ_BIT) { > + err = 0; > + if (oh->error == -ENOSYS) > + fc->no_interrupt = 1; > + else if (oh->error == -EAGAIN) { > + /* XXX Interrupts not handled yet */ > + /* err = queue_interrupt(req); */ > + pr_warn("Intrerupt EAGAIN not supported yet"); > + err = -EINVAL; > + } > + > + goto seterr; > + } > + > + return 0; > + > +seterr: > + pr_devel("%s:%d err=%d op=%d req-ret=%d", __func__, __LINE__, err, > + req->args->opcode, req->out.h.error); > + oh->error = err; > +err: > + pr_devel("%s:%d err=%d op=%d req-ret=%d", __func__, __LINE__, err, > + req->args->opcode, req->out.h.error); > + return err; > +} > + > +/* > + * Copy data from the ring buffer to the fuse request > + */ > +static int fuse_uring_copy_from_ring(struct fuse_ring *ring, > + struct fuse_req *req, > + struct fuse_ring_req *rreq) > +{ > + struct fuse_copy_state cs; > + struct fuse_args *args = req->args; > + > + fuse_copy_init(&cs, 0, NULL); > + cs.is_uring = 1; > + cs.ring.buf = rreq->in_out_arg; > + > + if (rreq->in_out_arg_len > ring->req_arg_len) { > + pr_devel("Max ring buffer len exceeded (%u vs %zu\n", > + rreq->in_out_arg_len, ring->req_arg_len); > + return -EINVAL; > + } > + cs.ring.buf_sz = rreq->in_out_arg_len; > + cs.req = req; > + > + pr_devel("%s:%d buf=%p len=%d args=%d\n", __func__, __LINE__, > + cs.ring.buf, cs.ring.buf_sz, args->out_numargs); > + > + return fuse_copy_out_args(&cs, args, rreq->in_out_arg_len); > +} > + > +/* > + * Copy data from the req to the ring buffer > + */ > +static int fuse_uring_copy_to_ring(struct fuse_ring *ring, struct fuse_req *req, > + struct fuse_ring_req *rreq) > +{ > + struct fuse_copy_state cs; > + struct fuse_args *args = req->args; > + int err; > + > + fuse_copy_init(&cs, 1, NULL); > + cs.is_uring = 1; > + cs.ring.buf = rreq->in_out_arg; > + cs.ring.buf_sz = ring->req_arg_len; > + cs.req = req; > + > + pr_devel("%s:%d buf=%p len=%d args=%d\n", __func__, __LINE__, > + cs.ring.buf, cs.ring.buf_sz, args->out_numargs); > + > + err = fuse_copy_args(&cs, args->in_numargs, args->in_pages, > + (struct fuse_arg *)args->in_args, 0); > + rreq->in_out_arg_len = cs.ring.offset; Is this ok if there's an error? I genuinely don't know, maybe add a comment for idiots like me? > + > + pr_devel("%s:%d buf=%p len=%d args=%d err=%d\n", __func__, __LINE__, > + cs.ring.buf, cs.ring.buf_sz, args->out_numargs, 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 void fuse_uring_send_to_ring(struct fuse_ring_ent *ring_ent, > + unsigned int issue_flags, bool send_in_task) > +{ > + struct fuse_ring *ring = ring_ent->queue->ring; > + struct fuse_ring_req *rreq = ring_ent->rreq; > + struct fuse_req *req = ring_ent->fuse_req; > + struct fuse_ring_queue *queue = ring_ent->queue; > + int err = 0; > + > + spin_lock(&queue->lock); > + > + if (WARN_ON(test_bit(FRRS_USERSPACE, &ring_ent->state) || > + (test_bit(FRRS_FREED, &ring_ent->state)))) { WARN_ON(x || b) Makes me sad when it trips because IDK which one it was, please make them have their own warn condition. Also I don't love using WARN_ON() in an if statement if it can be avoided, so maybe if (test_bit() || test_bit()) { WARN_ON_ONCE(test_bit(USERSPACE)); WARN_ON_ONCE(test_bit(FREED)); err = -EIO; } Also again I'm sorry for not bringing this up early, I'd prefer WARN_ON_ONCE(). History has shown me many a hung box because I thought this would never happen and now it's spewing stack traces to my slow ass serial console and I can't get the box to respond at all. > + pr_err("qid=%d tag=%d ring-req=%p buf_req=%p invalid state %lu on send\n", > + queue->qid, ring_ent->tag, ring_ent, rreq, > + ring_ent->state); > + err = -EIO; > + } else { > + set_bit(FRRS_USERSPACE, &ring_ent->state); > + list_add(&ring_ent->list, &queue->ent_in_userspace); > + } > + > + spin_unlock(&queue->lock); > + if (err) > + goto err; > + > + err = fuse_uring_copy_to_ring(ring, req, rreq); > + if (unlikely(err)) { > + spin_lock(&queue->lock); > + fuse_ring_ring_ent_unset_userspace(ring_ent); > + spin_unlock(&queue->lock); > + goto err; > + } > + > + /* ring req go directly into the shared memory buffer */ > + rreq->in = req->in.h; > + set_bit(FR_SENT, &req->flags); > + > + pr_devel("%s qid=%d tag=%d state=%lu cmd-done op=%d unique=%llu issue_flags=%u\n", > + __func__, ring_ent->queue->qid, ring_ent->tag, ring_ent->state, > + rreq->in.opcode, rreq->in.unique, issue_flags); > + > + if (send_in_task) > + io_uring_cmd_complete_in_task(ring_ent->cmd, > + fuse_uring_async_send_to_ring); > + else > + io_uring_cmd_done(ring_ent->cmd, 0, 0, issue_flags); > + > + return; > + > +err: > + fuse_uring_req_end_and_get_next(ring_ent, true, err, issue_flags); > +} > + > /* > * Put a ring request onto hold, it is no longer used for now. > */ > @@ -381,6 +574,104 @@ static void fuse_uring_ent_avail(struct fuse_ring_ent *ring_ent, > set_bit(FRRS_WAIT, &ring_ent->state); > } > > +/* > + * Assign a fuse queue entry to the given entry > + */ > +static void fuse_uring_add_req_to_ring_ent(struct fuse_ring_ent *ring_ent, > + struct fuse_req *req) > +{ > + clear_bit(FRRS_WAIT, &ring_ent->state); > + list_del_init(&req->list); > + clear_bit(FR_PENDING, &req->flags); > + ring_ent->fuse_req = req; > + set_bit(FRRS_FUSE_REQ, &ring_ent->state); > +} > + > +/* > + * Release a uring entry and fetch the next fuse request if available > + * > + * @return true if a new request has been fetched > + */ > +static bool fuse_uring_ent_release_and_fetch(struct fuse_ring_ent *ring_ent) > +{ > + struct fuse_req *req = NULL; > + struct fuse_ring_queue *queue = ring_ent->queue; > + struct list_head *req_queue = ring_ent->async ? > + &queue->async_fuse_req_queue : &queue->sync_fuse_req_queue; > + > + spin_lock(&ring_ent->queue->lock); > + fuse_uring_ent_avail(ring_ent, queue); > + if (!list_empty(req_queue)) { > + req = list_first_entry(req_queue, struct fuse_req, list); > + fuse_uring_add_req_to_ring_ent(ring_ent, req); > + list_del_init(&ring_ent->list); > + } > + spin_unlock(&ring_ent->queue->lock); > + > + return req ? true : false; > +} > + > +/* > + * Finalize a fuse request, then fetch and send the next entry, if available > + * > + * has lock/unlock/lock to avoid holding the lock on calling fuse_request_end > + */ > +static void fuse_uring_req_end_and_get_next(struct fuse_ring_ent *ring_ent, > + bool set_err, int error, > + unsigned int issue_flags) > +{ > + struct fuse_req *req = ring_ent->fuse_req; > + int has_next; > + > + if (set_err) > + req->out.h.error = error; The set_err thing seems redundant since we always have it set to true if error is set, so just drop this bit and set error if there's an error. > + > + clear_bit(FR_SENT, &req->flags); > + fuse_request_end(ring_ent->fuse_req); > + ring_ent->fuse_req = NULL; > + clear_bit(FRRS_FUSE_REQ, &ring_ent->state); > + > + has_next = fuse_uring_ent_release_and_fetch(ring_ent); > + if (has_next) { > + /* called within uring context - use provided flags */ > + fuse_uring_send_to_ring(ring_ent, issue_flags, false); > + } > +} > + > +/* > + * 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_and_release(struct fuse_dev *fud, > + struct fuse_ring_ent *ring_ent, > + unsigned int issue_flags) > +{ > + struct fuse_ring_req *rreq = ring_ent->rreq; > + struct fuse_req *req = ring_ent->fuse_req; > + ssize_t err = 0; > + bool set_err = false; > + > + req->out.h = rreq->out; > + > + err = fuse_uring_ring_ent_has_err(fud->fc->ring, ring_ent); > + if (err) { > + /* req->out.h.error already set */ > + pr_devel("%s:%d err=%zd oh->err=%d\n", __func__, __LINE__, err, > + req->out.h.error); > + goto out; > + } > + > + err = fuse_uring_copy_from_ring(fud->fc->ring, req, rreq); > + if (err) > + set_err = true; > + > +out: > + pr_devel("%s:%d ret=%zd op=%d req-ret=%d\n", __func__, __LINE__, err, > + req->args->opcode, req->out.h.error); > + fuse_uring_req_end_and_get_next(ring_ent, set_err, err, issue_flags); > +} > + > /* > * fuse_uring_req_fetch command handling > */ > @@ -566,6 +857,26 @@ int fuse_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) > > spin_unlock(&queue->lock); > break; > + case FUSE_URING_REQ_COMMIT_AND_FETCH: > + if (unlikely(!ring->ready)) { > + pr_info("commit and fetch, but fuse-uringis not ready."); > + goto err_unlock; > + } > + > + if (!test_bit(FRRS_USERSPACE, &ring_ent->state)) { > + pr_info("qid=%d tag=%d state %lu SQE already handled\n", > + queue->qid, ring_ent->tag, ring_ent->state); > + goto err_unlock; > + } > + > + fuse_ring_ring_ent_unset_userspace(ring_ent); > + spin_unlock(&queue->lock); > + > + WRITE_ONCE(ring_ent->cmd, cmd); > + fuse_uring_commit_and_release(fud, ring_ent, issue_flags); > + > + ret = 0; > + break; Hmm ok this changes my comments on the previous patch slightly, tho I think still it would be better to push this code into a helper as well and do the locking in there, let me go look at the resulting code...yeah ok I think it's still better to just have these two cases in their own helper. Thanks, Josef
diff --git a/fs/fuse/dev_uring.c b/fs/fuse/dev_uring.c index 48b1118b64f4..5269b3f8891e 100644 --- a/fs/fuse/dev_uring.c +++ b/fs/fuse/dev_uring.c @@ -31,12 +31,23 @@ #include <linux/topology.h> #include <linux/io_uring/cmd.h> +static void fuse_uring_req_end_and_get_next(struct fuse_ring_ent *ring_ent, + bool set_err, int error, + unsigned int issue_flags); + static void fuse_ring_ring_ent_unset_userspace(struct fuse_ring_ent *ent) { clear_bit(FRRS_USERSPACE, &ent->state); list_del_init(&ent->list); } +static void +fuse_uring_async_send_to_ring(struct io_uring_cmd *cmd, + unsigned int issue_flags) +{ + io_uring_cmd_done(cmd, 0, 0, issue_flags); +} + /* Update conn limits according to ring values */ static void fuse_uring_conn_cfg_limits(struct fuse_ring *ring) { @@ -350,6 +361,188 @@ int fuse_uring_queue_cfg(struct fuse_ring *ring, return 0; } +/* + * Checks for errors and stores it into the request + */ +static int fuse_uring_ring_ent_has_err(struct fuse_ring *ring, + struct fuse_ring_ent *ring_ent) +{ + struct fuse_conn *fc = ring->fc; + struct fuse_req *req = ring_ent->fuse_req; + struct fuse_out_header *oh = &req->out.h; + int err; + + if (oh->unique == 0) { + /* Not supportd through request based uring, this needs another + * ring from user space to kernel + */ + pr_warn("Unsupported fuse-notify\n"); + err = -EINVAL; + goto seterr; + } + + if (oh->error <= -512 || oh->error > 0) { + err = -EINVAL; + goto seterr; + } + + if (oh->error) { + err = oh->error; + pr_devel("%s:%d err=%d op=%d req-ret=%d", __func__, __LINE__, + err, req->args->opcode, req->out.h.error); + goto err; /* error already set */ + } + + if ((oh->unique & ~FUSE_INT_REQ_BIT) != req->in.h.unique) { + pr_warn("Unpexted seqno mismatch, expected: %llu got %llu\n", + req->in.h.unique, oh->unique & ~FUSE_INT_REQ_BIT); + err = -ENOENT; + goto seterr; + } + + /* Is it an interrupt reply ID? */ + if (oh->unique & FUSE_INT_REQ_BIT) { + err = 0; + if (oh->error == -ENOSYS) + fc->no_interrupt = 1; + else if (oh->error == -EAGAIN) { + /* XXX Interrupts not handled yet */ + /* err = queue_interrupt(req); */ + pr_warn("Intrerupt EAGAIN not supported yet"); + err = -EINVAL; + } + + goto seterr; + } + + return 0; + +seterr: + pr_devel("%s:%d err=%d op=%d req-ret=%d", __func__, __LINE__, err, + req->args->opcode, req->out.h.error); + oh->error = err; +err: + pr_devel("%s:%d err=%d op=%d req-ret=%d", __func__, __LINE__, err, + req->args->opcode, req->out.h.error); + return err; +} + +/* + * Copy data from the ring buffer to the fuse request + */ +static int fuse_uring_copy_from_ring(struct fuse_ring *ring, + struct fuse_req *req, + struct fuse_ring_req *rreq) +{ + struct fuse_copy_state cs; + struct fuse_args *args = req->args; + + fuse_copy_init(&cs, 0, NULL); + cs.is_uring = 1; + cs.ring.buf = rreq->in_out_arg; + + if (rreq->in_out_arg_len > ring->req_arg_len) { + pr_devel("Max ring buffer len exceeded (%u vs %zu\n", + rreq->in_out_arg_len, ring->req_arg_len); + return -EINVAL; + } + cs.ring.buf_sz = rreq->in_out_arg_len; + cs.req = req; + + pr_devel("%s:%d buf=%p len=%d args=%d\n", __func__, __LINE__, + cs.ring.buf, cs.ring.buf_sz, args->out_numargs); + + return fuse_copy_out_args(&cs, args, rreq->in_out_arg_len); +} + +/* + * Copy data from the req to the ring buffer + */ +static int fuse_uring_copy_to_ring(struct fuse_ring *ring, struct fuse_req *req, + struct fuse_ring_req *rreq) +{ + struct fuse_copy_state cs; + struct fuse_args *args = req->args; + int err; + + fuse_copy_init(&cs, 1, NULL); + cs.is_uring = 1; + cs.ring.buf = rreq->in_out_arg; + cs.ring.buf_sz = ring->req_arg_len; + cs.req = req; + + pr_devel("%s:%d buf=%p len=%d args=%d\n", __func__, __LINE__, + cs.ring.buf, cs.ring.buf_sz, args->out_numargs); + + err = fuse_copy_args(&cs, args->in_numargs, args->in_pages, + (struct fuse_arg *)args->in_args, 0); + rreq->in_out_arg_len = cs.ring.offset; + + pr_devel("%s:%d buf=%p len=%d args=%d err=%d\n", __func__, __LINE__, + cs.ring.buf, cs.ring.buf_sz, args->out_numargs, 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 void fuse_uring_send_to_ring(struct fuse_ring_ent *ring_ent, + unsigned int issue_flags, bool send_in_task) +{ + struct fuse_ring *ring = ring_ent->queue->ring; + struct fuse_ring_req *rreq = ring_ent->rreq; + struct fuse_req *req = ring_ent->fuse_req; + struct fuse_ring_queue *queue = ring_ent->queue; + int err = 0; + + spin_lock(&queue->lock); + + if (WARN_ON(test_bit(FRRS_USERSPACE, &ring_ent->state) || + (test_bit(FRRS_FREED, &ring_ent->state)))) { + pr_err("qid=%d tag=%d ring-req=%p buf_req=%p invalid state %lu on send\n", + queue->qid, ring_ent->tag, ring_ent, rreq, + ring_ent->state); + err = -EIO; + } else { + set_bit(FRRS_USERSPACE, &ring_ent->state); + list_add(&ring_ent->list, &queue->ent_in_userspace); + } + + spin_unlock(&queue->lock); + if (err) + goto err; + + err = fuse_uring_copy_to_ring(ring, req, rreq); + if (unlikely(err)) { + spin_lock(&queue->lock); + fuse_ring_ring_ent_unset_userspace(ring_ent); + spin_unlock(&queue->lock); + goto err; + } + + /* ring req go directly into the shared memory buffer */ + rreq->in = req->in.h; + set_bit(FR_SENT, &req->flags); + + pr_devel("%s qid=%d tag=%d state=%lu cmd-done op=%d unique=%llu issue_flags=%u\n", + __func__, ring_ent->queue->qid, ring_ent->tag, ring_ent->state, + rreq->in.opcode, rreq->in.unique, issue_flags); + + if (send_in_task) + io_uring_cmd_complete_in_task(ring_ent->cmd, + fuse_uring_async_send_to_ring); + else + io_uring_cmd_done(ring_ent->cmd, 0, 0, issue_flags); + + return; + +err: + fuse_uring_req_end_and_get_next(ring_ent, true, err, issue_flags); +} + /* * Put a ring request onto hold, it is no longer used for now. */ @@ -381,6 +574,104 @@ static void fuse_uring_ent_avail(struct fuse_ring_ent *ring_ent, set_bit(FRRS_WAIT, &ring_ent->state); } +/* + * Assign a fuse queue entry to the given entry + */ +static void fuse_uring_add_req_to_ring_ent(struct fuse_ring_ent *ring_ent, + struct fuse_req *req) +{ + clear_bit(FRRS_WAIT, &ring_ent->state); + list_del_init(&req->list); + clear_bit(FR_PENDING, &req->flags); + ring_ent->fuse_req = req; + set_bit(FRRS_FUSE_REQ, &ring_ent->state); +} + +/* + * Release a uring entry and fetch the next fuse request if available + * + * @return true if a new request has been fetched + */ +static bool fuse_uring_ent_release_and_fetch(struct fuse_ring_ent *ring_ent) +{ + struct fuse_req *req = NULL; + struct fuse_ring_queue *queue = ring_ent->queue; + struct list_head *req_queue = ring_ent->async ? + &queue->async_fuse_req_queue : &queue->sync_fuse_req_queue; + + spin_lock(&ring_ent->queue->lock); + fuse_uring_ent_avail(ring_ent, queue); + if (!list_empty(req_queue)) { + req = list_first_entry(req_queue, struct fuse_req, list); + fuse_uring_add_req_to_ring_ent(ring_ent, req); + list_del_init(&ring_ent->list); + } + spin_unlock(&ring_ent->queue->lock); + + return req ? true : false; +} + +/* + * Finalize a fuse request, then fetch and send the next entry, if available + * + * has lock/unlock/lock to avoid holding the lock on calling fuse_request_end + */ +static void fuse_uring_req_end_and_get_next(struct fuse_ring_ent *ring_ent, + bool set_err, int error, + unsigned int issue_flags) +{ + struct fuse_req *req = ring_ent->fuse_req; + int has_next; + + if (set_err) + req->out.h.error = error; + + clear_bit(FR_SENT, &req->flags); + fuse_request_end(ring_ent->fuse_req); + ring_ent->fuse_req = NULL; + clear_bit(FRRS_FUSE_REQ, &ring_ent->state); + + has_next = fuse_uring_ent_release_and_fetch(ring_ent); + if (has_next) { + /* called within uring context - use provided flags */ + fuse_uring_send_to_ring(ring_ent, issue_flags, false); + } +} + +/* + * 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_and_release(struct fuse_dev *fud, + struct fuse_ring_ent *ring_ent, + unsigned int issue_flags) +{ + struct fuse_ring_req *rreq = ring_ent->rreq; + struct fuse_req *req = ring_ent->fuse_req; + ssize_t err = 0; + bool set_err = false; + + req->out.h = rreq->out; + + err = fuse_uring_ring_ent_has_err(fud->fc->ring, ring_ent); + if (err) { + /* req->out.h.error already set */ + pr_devel("%s:%d err=%zd oh->err=%d\n", __func__, __LINE__, err, + req->out.h.error); + goto out; + } + + err = fuse_uring_copy_from_ring(fud->fc->ring, req, rreq); + if (err) + set_err = true; + +out: + pr_devel("%s:%d ret=%zd op=%d req-ret=%d\n", __func__, __LINE__, err, + req->args->opcode, req->out.h.error); + fuse_uring_req_end_and_get_next(ring_ent, set_err, err, issue_flags); +} + /* * fuse_uring_req_fetch command handling */ @@ -566,6 +857,26 @@ int fuse_uring_cmd(struct io_uring_cmd *cmd, unsigned int issue_flags) spin_unlock(&queue->lock); break; + case FUSE_URING_REQ_COMMIT_AND_FETCH: + if (unlikely(!ring->ready)) { + pr_info("commit and fetch, but fuse-uringis not ready."); + goto err_unlock; + } + + if (!test_bit(FRRS_USERSPACE, &ring_ent->state)) { + pr_info("qid=%d tag=%d state %lu SQE already handled\n", + queue->qid, ring_ent->tag, ring_ent->state); + goto err_unlock; + } + + fuse_ring_ring_ent_unset_userspace(ring_ent); + spin_unlock(&queue->lock); + + WRITE_ONCE(ring_ent->cmd, cmd); + fuse_uring_commit_and_release(fud, ring_ent, issue_flags); + + ret = 0; + break; default: ret = -EINVAL; pr_devel("Unknown uring command %d", cmd_op);
This adds support for fuse request completion through ring SQEs (FUSE_URING_REQ_COMMIT_AND_FETCH handling). After committing the ring entry it becomes available for new fuse requests. Handling of requests through the ring (SQE/CQE handling) is complete now. Fuse request data are copied through the mmaped ring buffer, there is no support for any zero copy yet. Signed-off-by: Bernd Schubert <bschubert@ddn.com> --- fs/fuse/dev_uring.c | 311 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 311 insertions(+)