[PATCH liburing v2 1/5] Add CQ ring 'flags' field

From: Stefano Garzarella
Date: Wed May 20 2020 - 13:07:36 EST


io_uring provides the new CQ ring 'flags' field if 'cq_off.flags'
is not zero. In this case we set the 'cq->kflags' pointer, otherwise
it will be NULL.

Signed-off-by: Stefano Garzarella <sgarzare@xxxxxxxxxx>
---
src/include/liburing.h | 1 +
src/include/liburing/io_uring.h | 4 +++-
src/setup.c | 2 ++
3 files changed, 6 insertions(+), 1 deletion(-)

diff --git a/src/include/liburing.h b/src/include/liburing.h
index 4311325..adc8db9 100644
--- a/src/include/liburing.h
+++ b/src/include/liburing.h
@@ -41,6 +41,7 @@ struct io_uring_cq {
unsigned *ktail;
unsigned *kring_mask;
unsigned *kring_entries;
+ unsigned *kflags;
unsigned *koverflow;
struct io_uring_cqe *cqes;

diff --git a/src/include/liburing/io_uring.h b/src/include/liburing/io_uring.h
index a279151..9860a8a 100644
--- a/src/include/liburing/io_uring.h
+++ b/src/include/liburing/io_uring.h
@@ -205,7 +205,9 @@ struct io_cqring_offsets {
__u32 ring_entries;
__u32 overflow;
__u32 cqes;
- __u64 resv[2];
+ __u32 flags;
+ __u32 resv1;
+ __u64 resv2;
};

/*
diff --git a/src/setup.c b/src/setup.c
index f783b6a..860c112 100644
--- a/src/setup.c
+++ b/src/setup.c
@@ -76,6 +76,8 @@ err:
cq->kring_entries = cq->ring_ptr + p->cq_off.ring_entries;
cq->koverflow = cq->ring_ptr + p->cq_off.overflow;
cq->cqes = cq->ring_ptr + p->cq_off.cqes;
+ if (p->cq_off.flags)
+ cq->kflags = cq->ring_ptr + p->cq_off.flags;
return 0;
}

--
2.25.4