nvme/io_uring: use helper for polled completions

NVMe is making up issue_flags, which is a no-no in general, and to make
matters worse, they are completely the wrong ones. For a pure polled
request, which it does check for, we're already inside the
ctx->uring_lock when the completions are run off io_do_iopoll(). Hence
the correct flag would be '0' rather than IO_URING_F_UNLOCKED.

Reviewed-by: Pavel Begunkov <asml.silence@gmail.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Jens Axboe 2024-03-19 17:10:50 -06:00
parent 36a005b9c6
commit 1afdb76038
2 changed files with 22 additions and 4 deletions

View File

@ -423,13 +423,20 @@ static enum rq_end_io_ret nvme_uring_cmd_end_io(struct request *req,
pdu->result = le64_to_cpu(nvme_req(req)->result.u64);
/*
* For iopoll, complete it directly.
* For iopoll, complete it directly. Note that using the uring_cmd
* helper for this is safe only because we check blk_rq_is_poll().
* As that returns false if we're NOT on a polled queue, then it's
* safe to use the polled completion helper.
*
* Otherwise, move the completion to task work.
*/
if (blk_rq_is_poll(req))
nvme_uring_task_cb(ioucmd, IO_URING_F_UNLOCKED);
else
if (blk_rq_is_poll(req)) {
if (pdu->bio)
blk_rq_unmap_user(pdu->bio);
io_uring_cmd_iopoll_done(ioucmd, pdu->result, pdu->status);
} else {
io_uring_cmd_do_in_task_lazy(ioucmd, nvme_uring_task_cb);
}
return RQ_END_IO_FREE;
}

View File

@ -69,6 +69,17 @@ static inline void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
}
#endif
/*
* Polled completions must ensure they are coming from a poll queue, and
* hence are completed inside the usual poll handling loops.
*/
static inline void io_uring_cmd_iopoll_done(struct io_uring_cmd *ioucmd,
ssize_t ret, ssize_t res2)
{
lockdep_assert(in_task());
io_uring_cmd_done(ioucmd, ret, res2, 0);
}
/* users must follow the IOU_F_TWQ_LAZY_WAKE semantics */
static inline void io_uring_cmd_do_in_task_lazy(struct io_uring_cmd *ioucmd,
void (*task_work_cb)(struct io_uring_cmd *, unsigned))