On Fri, Apr 07, 2023 at 12:16:33PM -0700, Keith Busch wrote:
From: Keith Busch <kbusch@xxxxxxxxxx>
Set the bio's bi_end_io to handle the cleanup so that uring_cmd doesn't
need this complex pdu->{bio,req} switchero and restore.
Signed-off-by: Keith Busch <kbusch@xxxxxxxxxx>
---
drivers/nvme/host/ioctl.c | 26 +++++++++-----------------
1 file changed, 9 insertions(+), 17 deletions(-)
diff --git a/drivers/nvme/host/ioctl.c b/drivers/nvme/host/ioctl.c
index d24ea2e051564..278c57ee0db91 100644
--- a/drivers/nvme/host/ioctl.c
+++ b/drivers/nvme/host/ioctl.c
@@ -159,6 +159,11 @@ static struct request *nvme_alloc_user_request(struct request_queue *q,
return req;
}
+static void nvme_uring_bio_end_io(struct bio *bio)
+{
+ blk_rq_unmap_user(bio);
+}
+
static int nvme_map_user_request(struct request *req, u64 ubuffer,
unsigned bufflen, void __user *meta_buffer, unsigned meta_len,
u32 meta_seed, void **metap, struct io_uring_cmd *ioucmd,
@@ -204,6 +209,7 @@ static int nvme_map_user_request(struct request *req, u64 ubuffer,
*metap = meta;
}
+ bio->bi_end_io = nvme_uring_bio_end_io;
return ret;
out_unmap:
@@ -249,8 +255,6 @@ static int nvme_submit_user_cmd(struct request_queue *q,
if (meta)
ret = nvme_finish_user_metadata(req, meta_buffer, meta,
meta_len, ret);
- if (bio)
- blk_rq_unmap_user(bio);
Is it safe to call blk_rq_unamp_user in irq context?
Agree that current code does some complex stuff, but that's to ensure
what the code-comment [1] says.
Also for polled-io, new-code will hit this warn-on [2] on calling
bio_put_percpu_cache.
[1]
623 * A matching blk_rq_unmap_user() must be issued at the end of I/O, while
624 * still in process context.
625 */
626 int blk_rq_map_user_iov(struct request_queue *q, struct request *rq,
627 struct rq_map_data *map_data,
[2]
773 if ((bio->bi_opf & REQ_POLLED) && !WARN_ON_ONCE(in_interrupt())) {
774 bio->bi_next = cache->free_list;
