Commit 3e47d7fa authored by Konrad Sztyber's avatar Konrad Sztyber Committed by Tomasz Zawadzki
Browse files

sock: asynchronous readv interface 



This patch defines a new function, spdk_sock_readv_async(), which allows
the user to send a readv request and receive a callback once the
supplied buffer is filled with data from the socket.  It works simiarly
to asynchronous writes, but there can only be a single outstanding read
request at a time.

For now, the interface isn't implemented and any calls will return
-ENOTSUP.  Subsequent patches will add support for it in the uring
module and as well as emulation in the posix module.

Signed-off-by: default avatarKonrad Sztyber <konrad.sztyber@intel.com>
Change-Id: I924e2cdade49ffa18be6390109dc7e65c2728087
Reviewed-on: https://review.spdk.io/gerrit/c/spdk/spdk/+/12170


Tested-by: default avatarSPDK CI Jenkins <sys_sgci@intel.com>
Community-CI: Broadcom CI <spdk-ci.pdl@broadcom.com>
Community-CI: Mellanox Build Bot
Reviewed-by: default avatarShuhei Matsumoto <smatsumoto@nvidia.com>
Reviewed-by: default avatarBen Walker <benjamin.walker@intel.com>
parent 20cd4841

include/spdk/sock.h

+15 −1
Original line number Diff line number Diff line
@@ -34,7 +34,11 @@ struct spdk_sock_group; 
 */

struct spdk_sock_request {

	/* When the request is completed, this callback will be called.

	 * err will be 0 on success or a negated errno value on failure. */

	 * On success, err will be:

	 *   - for writes: 0,

	 *   - for reads: number of bytes read.

	 * On failure: negative errno value.

	 */

	void	(*cb_fn)(void *cb_arg, int err);

	void				*cb_arg;
@@ -332,6 +336,16 @@ void spdk_sock_writev_async(struct spdk_sock *sock, struct spdk_sock_request *re 
 */

ssize_t spdk_sock_readv(struct spdk_sock *sock, struct iovec *iov, int iovcnt);



/**

 * Read message from the given socket asynchronously, calling the provided callback when the whole

 * buffer is filled or an error is encountered.  Only a single read request can be active at a time

 * (including synchronous reads).

 *

 * \param sock Socket to receive message.

 * \param req The read request to submit.

 */

void spdk_sock_readv_async(struct spdk_sock *sock, struct spdk_sock_request *req);



/**

 * Set the value used to specify the low water mark (in bytes) for this socket.

 *

include/spdk_internal/sock.h

+8 −0
Original line number Diff line number Diff line
@@ -34,6 +34,7 @@ struct spdk_sock { 


	TAILQ_HEAD(, spdk_sock_request)	queued_reqs;

	TAILQ_HEAD(, spdk_sock_request)	pending_reqs;

	struct spdk_sock_request	*read_req;

	int				queued_iovcnt;

	int				cb_cnt;

	spdk_sock_cb			cb_fn;
@@ -77,6 +78,7 @@ struct spdk_net_impl { 
	ssize_t (*writev)(struct spdk_sock *sock, struct iovec *iov, int iovcnt);



	void (*writev_async)(struct spdk_sock *sock, struct spdk_sock_request *req);

	void (*readv_async)(struct spdk_sock *sock, struct spdk_sock_request *req);

	int (*flush)(struct spdk_sock *sock);



	int (*set_recvlowat)(struct spdk_sock *sock, int nbytes);
@@ -202,6 +204,12 @@ spdk_sock_abort_requests(struct spdk_sock *sock) 


		req = TAILQ_FIRST(&sock->queued_reqs);

	}



	req = sock->read_req;

	if (req != NULL) {

		sock->read_req = NULL;

		req->cb_fn(req->cb_arg, -ECANCELED);

	}

	assert(sock->cb_cnt > 0);

	sock->cb_cnt--;

lib/sock/sock.c

+19 −0
Original line number Diff line number Diff line
@@ -476,6 +476,25 @@ spdk_sock_readv(struct spdk_sock *sock, struct iovec *iov, int iovcnt) 
	return sock->net_impl->readv(sock, iov, iovcnt);

}



void

spdk_sock_readv_async(struct spdk_sock *sock, struct spdk_sock_request *req)

{

	assert(req->cb_fn != NULL);



	if (spdk_unlikely(sock == NULL || sock->flags.closed)) {

		req->cb_fn(req->cb_arg, -EBADF);

		return;

	}



	/* The socket needs to be part of a poll group */

	if (spdk_unlikely(sock->group_impl == NULL)) {

		req->cb_fn(req->cb_arg, -EPERM);

		return;

	}



	sock->net_impl->readv_async(sock, req);

}



ssize_t

spdk_sock_writev(struct spdk_sock *sock, struct iovec *iov, int iovcnt)

{

lib/sock/spdk_sock.map

+1 −0
Original line number Diff line number Diff line
@@ -15,6 +15,7 @@ 
	spdk_sock_writev;

	spdk_sock_writev_async;

	spdk_sock_readv;

	spdk_sock_readv_async;

	spdk_sock_set_recvlowat;

	spdk_sock_set_recvbuf;

	spdk_sock_set_sendbuf;

module/sock/posix/posix.c

+7 −0
Original line number Diff line number Diff line
@@ -1368,6 +1368,12 @@ posix_sock_recv(struct spdk_sock *sock, void *buf, size_t len) 
	return posix_sock_readv(sock, iov, 1);

}



static void

posix_sock_readv_async(struct spdk_sock *sock, struct spdk_sock_request *req)

{

	req->cb_fn(req->cb_arg, -ENOTSUP);

}



static ssize_t

posix_sock_writev(struct spdk_sock *_sock, struct iovec *iov, int iovcnt)

{
@@ -1957,6 +1963,7 @@ static struct spdk_net_impl g_posix_net_impl = { 
	.close		= posix_sock_close,

	.recv		= posix_sock_recv,

	.readv		= posix_sock_readv,

	.readv_async	= posix_sock_readv_async,

	.writev		= posix_sock_writev,

	.writev_async	= posix_sock_writev_async,

	.flush		= posix_sock_flush,