[PATCH 4/5] io_uring/kbuf: pass in 'len' argument for buffer commit

[Jens Axboe <axboe@kernel.dk>]

In preparation for needing the consumed length, pass in the length being
completed. Unused right now, but will be used when it is possible to
partially consume a buffer.

Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
 io_uring/io_uring.c |  2 +-
 io_uring/kbuf.c     | 10 +++++-----
 io_uring/kbuf.h     | 33 +++++++++++++++++----------------
 io_uring/net.c      |  8 ++++----
 io_uring/rw.c       |  8 ++++----
 5 files changed, 31 insertions(+), 30 deletions(-)

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 80bb6e2374e9..1aca501efaf6 100644
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -904,7 +904,7 @@ void io_req_defer_failed(struct io_kiocb *req, s32 res)
 	lockdep_assert_held(&req->ctx->uring_lock);
 
 	req_set_fail(req);
-	io_req_set_res(req, res, io_put_kbuf(req, IO_URING_F_UNLOCKED));
+	io_req_set_res(req, res, io_put_kbuf(req, res, IO_URING_F_UNLOCKED));
 	if (def->fail)
 		def->fail(req);
 	io_req_complete_defer(req);
diff --git a/io_uring/kbuf.c b/io_uring/kbuf.c
index 297c1d2c3c27..55d01861d8c5 100644
--- a/io_uring/kbuf.c
+++ b/io_uring/kbuf.c
@@ -70,7 +70,7 @@ bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags)
 	return true;
 }
 
-void __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags)
+void __io_put_kbuf(struct io_kiocb *req, int len, unsigned issue_flags)
 {
 	/*
 	 * We can add this buffer back to two lists:
@@ -88,12 +88,12 @@ void __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags)
 		struct io_ring_ctx *ctx = req->ctx;
 
 		spin_lock(&ctx->completion_lock);
-		__io_put_kbuf_list(req, &ctx->io_buffers_comp);
+		__io_put_kbuf_list(req, len, &ctx->io_buffers_comp);
 		spin_unlock(&ctx->completion_lock);
 	} else {
 		lockdep_assert_held(&req->ctx->uring_lock);
 
-		__io_put_kbuf_list(req, &req->ctx->io_buffers_cache);
+		__io_put_kbuf_list(req, len, &req->ctx->io_buffers_cache);
 	}
 }
 
@@ -165,7 +165,7 @@ static void __user *io_ring_buffer_select(struct io_kiocb *req, size_t *len,
 		 * the transfer completes (or if we get -EAGAIN and must poll of
 		 * retry).
 		 */
-		io_kbuf_commit(req, bl, 1);
+		io_kbuf_commit(req, bl, *len, 1);
 		req->buf_list = NULL;
 	}
 	return u64_to_user_ptr(buf->addr);
@@ -291,7 +291,7 @@ int io_buffers_select(struct io_kiocb *req, struct buf_sel_arg *arg,
 		 */
 		if (ret > 0) {
 			req->flags |= REQ_F_BUFFERS_COMMIT | REQ_F_BL_NO_RECYCLE;
-			io_kbuf_commit(req, bl, ret);
+			io_kbuf_commit(req, bl, arg->out_len, ret);
 		}
 	} else {
 		ret = io_provided_buffers_select(req, &arg->out_len, bl, arg->iovs);
diff --git a/io_uring/kbuf.h b/io_uring/kbuf.h
index 4c34ff3144b9..b41e2a0a0505 100644
--- a/io_uring/kbuf.h
+++ b/io_uring/kbuf.h
@@ -77,7 +77,7 @@ int io_register_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg);
 int io_unregister_pbuf_ring(struct io_ring_ctx *ctx, void __user *arg);
 int io_register_pbuf_status(struct io_ring_ctx *ctx, void __user *arg);
 
-void __io_put_kbuf(struct io_kiocb *req, unsigned issue_flags);
+void __io_put_kbuf(struct io_kiocb *req, int len, unsigned issue_flags);
 
 bool io_kbuf_recycle_legacy(struct io_kiocb *req, unsigned issue_flags);
 
@@ -125,7 +125,7 @@ static inline bool io_kbuf_recycle(struct io_kiocb *req, unsigned issue_flags)
 #define io_ring_head_to_buf(br, head, mask)	&(br)->bufs[(head) & (mask)]
 
 static inline void io_kbuf_commit(struct io_kiocb *req,
-				  struct io_buffer_list *bl, int nr)
+				  struct io_buffer_list *bl, int len, int nr)
 {
 	if (unlikely(!(req->flags & REQ_F_BUFFERS_COMMIT)))
 		return;
@@ -133,22 +133,22 @@ static inline void io_kbuf_commit(struct io_kiocb *req,
 	req->flags &= ~REQ_F_BUFFERS_COMMIT;
 }
 
-static inline void __io_put_kbuf_ring(struct io_kiocb *req, int nr)
+static inline void __io_put_kbuf_ring(struct io_kiocb *req, int len, int nr)
 {
 	struct io_buffer_list *bl = req->buf_list;
 
 	if (bl) {
-		io_kbuf_commit(req, bl, nr);
+		io_kbuf_commit(req, bl, len, nr);
 		req->buf_index = bl->bgid;
 	}
 	req->flags &= ~REQ_F_BUFFER_RING;
 }
 
-static inline void __io_put_kbuf_list(struct io_kiocb *req,
+static inline void __io_put_kbuf_list(struct io_kiocb *req, int len,
 				      struct list_head *list)
 {
 	if (req->flags & REQ_F_BUFFER_RING) {
-		__io_put_kbuf_ring(req, 1);
+		__io_put_kbuf_ring(req, len, 1);
 	} else {
 		req->buf_index = req->kbuf->bgid;
 		list_add(&req->kbuf->list, list);
@@ -163,11 +163,12 @@ static inline void io_kbuf_drop(struct io_kiocb *req)
 	if (!(req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING)))
 		return;
 
-	__io_put_kbuf_list(req, &req->ctx->io_buffers_comp);
+	/* len == 0 is fine here, non-ring will always drop all of it */
+	__io_put_kbuf_list(req, 0, &req->ctx->io_buffers_comp);
 }
 
-static inline unsigned int __io_put_kbufs(struct io_kiocb *req, int nbufs,
-					  unsigned issue_flags)
+static inline unsigned int __io_put_kbufs(struct io_kiocb *req, int len,
+					  int nbufs, unsigned issue_flags)
 {
 	unsigned int ret;
 
@@ -176,21 +177,21 @@ static inline unsigned int __io_put_kbufs(struct io_kiocb *req, int nbufs,
 
 	ret = IORING_CQE_F_BUFFER | (req->buf_index << IORING_CQE_BUFFER_SHIFT);
 	if (req->flags & REQ_F_BUFFER_RING)
-		__io_put_kbuf_ring(req, nbufs);
+		__io_put_kbuf_ring(req, len, nbufs);
 	else
-		__io_put_kbuf(req, issue_flags);
+		__io_put_kbuf(req, len, issue_flags);
 	return ret;
 }
 
-static inline unsigned int io_put_kbuf(struct io_kiocb *req,
+static inline unsigned int io_put_kbuf(struct io_kiocb *req, int len,
 				       unsigned issue_flags)
 {
-	return __io_put_kbufs(req, 1, issue_flags);
+	return __io_put_kbufs(req, len, 1, issue_flags);
 }
 
-static inline unsigned int io_put_kbufs(struct io_kiocb *req, int nbufs,
-					unsigned issue_flags)
+static inline unsigned int io_put_kbufs(struct io_kiocb *req, int len,
+					int nbufs, unsigned issue_flags)
 {
-	return __io_put_kbufs(req, nbufs, issue_flags);
+	return __io_put_kbufs(req, len, nbufs, issue_flags);
 }
 #endif
diff --git a/io_uring/net.c b/io_uring/net.c
index cc81bcacdc1b..f10f5a22d66a 100644
--- a/io_uring/net.c
+++ b/io_uring/net.c
@@ -497,11 +497,11 @@ static inline bool io_send_finish(struct io_kiocb *req, int *ret,
 	unsigned int cflags;
 
 	if (!(sr->flags & IORING_RECVSEND_BUNDLE)) {
-		cflags = io_put_kbuf(req, issue_flags);
+		cflags = io_put_kbuf(req, *ret, issue_flags);
 		goto finish;
 	}
 
-	cflags = io_put_kbufs(req, io_bundle_nbufs(kmsg, *ret), issue_flags);
+	cflags = io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret), issue_flags);
 
 	if (bundle_finished || req->flags & REQ_F_BL_EMPTY)
 		goto finish;
@@ -842,13 +842,13 @@ static inline bool io_recv_finish(struct io_kiocb *req, int *ret,
 		cflags |= IORING_CQE_F_SOCK_NONEMPTY;
 
 	if (sr->flags & IORING_RECVSEND_BUNDLE) {
-		cflags |= io_put_kbufs(req, io_bundle_nbufs(kmsg, *ret),
+		cflags |= io_put_kbufs(req, *ret, io_bundle_nbufs(kmsg, *ret),
 				      issue_flags);
 		/* bundle with no more immediate buffers, we're done */
 		if (req->flags & REQ_F_BL_EMPTY)
 			goto finish;
 	} else {
-		cflags |= io_put_kbuf(req, issue_flags);
+		cflags |= io_put_kbuf(req, *ret, issue_flags);
 	}
 
 	/*
diff --git a/io_uring/rw.c b/io_uring/rw.c
index c004d21e2f12..f5e0694538b9 100644
--- a/io_uring/rw.c
+++ b/io_uring/rw.c
@@ -511,7 +511,7 @@ void io_req_rw_complete(struct io_kiocb *req, struct io_tw_state *ts)
 	io_req_io_end(req);
 
 	if (req->flags & (REQ_F_BUFFER_SELECTED|REQ_F_BUFFER_RING))
-		req->cqe.flags |= io_put_kbuf(req, 0);
+		req->cqe.flags |= io_put_kbuf(req, req->cqe.res, 0);
 
 	io_req_rw_cleanup(req, 0);
 	io_req_task_complete(req, ts);
@@ -593,7 +593,7 @@ static int kiocb_done(struct io_kiocb *req, ssize_t ret,
 			 */
 			io_req_io_end(req);
 			io_req_set_res(req, final_ret,
-				       io_put_kbuf(req, issue_flags));
+				       io_put_kbuf(req, ret, issue_flags));
 			io_req_rw_cleanup(req, issue_flags);
 			return IOU_OK;
 		}
@@ -975,7 +975,7 @@ int io_read_mshot(struct io_kiocb *req, unsigned int issue_flags)
 		 * Put our buffer and post a CQE. If we fail to post a CQE, then
 		 * jump to the termination path. This request is then done.
 		 */
-		cflags = io_put_kbuf(req, issue_flags);
+		cflags = io_put_kbuf(req, ret, issue_flags);
 		rw->len = 0; /* similarly to above, reset len to 0 */
 
 		if (io_req_post_cqe(req, ret, cflags | IORING_CQE_F_MORE)) {
@@ -1167,7 +1167,7 @@ int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin)
 		if (!smp_load_acquire(&req->iopoll_completed))
 			break;
 		nr_events++;
-		req->cqe.flags = io_put_kbuf(req, 0);
+		req->cqe.flags = io_put_kbuf(req, req->cqe.res, 0);
 		if (req->opcode != IORING_OP_URING_CMD)
 			io_req_rw_cleanup(req, 0);
 	}
-- 
2.45.2