Commit d913ed17 authored by Pavel Shilovsky's avatar Pavel Shilovsky Committed by Steve French
Browse files

CIFS: Optimize cifs_user_read() in a short read case on reconnects 



by filling the output buffer with a data got from a partially received
response and requesting the remaining data from the server. This is
suitable for non-signed connections.

Signed-off-by: default avatarPavel Shilovsky <pshilovsky@samba.org>
Signed-off-by: default avatarSteve French <smfrench@gmail.com>
parent fb8a3e52

fs/cifs/cifssmb.c

+6 −0
Original line number Diff line number Diff line
@@ -1561,6 +1561,12 @@ cifs_readv_callback(struct mid_q_entry *mid) 
	case MID_REQUEST_SUBMITTED:

	case MID_RETRY_NEEDED:

		rdata->result = -EAGAIN;

		if (server->sign && rdata->got_bytes)

			/* reset bytes number since we can not check a sign */

			rdata->got_bytes = 0;

		/* FIXME: should this be counted toward the initiating task? */

		task_io_account_read(rdata->got_bytes);

		cifs_stats_bytes_read(tcon, rdata->got_bytes);

		break;

	default:

		rdata->result = -EIO;

fs/cifs/file.c

+20 −3
Original line number Diff line number Diff line
@@ -3030,13 +3030,30 @@ ssize_t cifs_user_readv(struct kiocb *iocb, struct iov_iter *to) 
			else if (rdata->result == -EAGAIN) {

				/* resend call if it's a retryable error */

				struct list_head tmp_list;

				unsigned int got_bytes = rdata->got_bytes;



				list_del_init(&rdata->list);

				INIT_LIST_HEAD(&tmp_list);



				rc = cifs_send_async_read(rdata->offset,

						rdata->bytes, rdata->cfile,

						cifs_sb, &tmp_list);

				/*

				 * Got a part of data and then reconnect has

				 * happened -- fill the buffer and continue

				 * reading.

				 */

				if (got_bytes && got_bytes < rdata->bytes) {

					rc = cifs_readdata_to_iov(rdata, to);

					if (rc) {

						kref_put(&rdata->refcount,

						cifs_uncached_readdata_release);

						continue;

					}

				}



				rc = cifs_send_async_read(

						rdata->offset + got_bytes,

						rdata->bytes - got_bytes,

						rdata->cfile, cifs_sb,

						&tmp_list);



				list_splice(&tmp_list, &rdata_list);

fs/cifs/smb2pdu.c

+6 −0
Original line number Diff line number Diff line
@@ -1729,6 +1729,12 @@ smb2_readv_callback(struct mid_q_entry *mid) 
	case MID_REQUEST_SUBMITTED:

	case MID_RETRY_NEEDED:

		rdata->result = -EAGAIN;

		if (server->sign && rdata->got_bytes)

			/* reset bytes number since we can not check a sign */

			rdata->got_bytes = 0;

		/* FIXME: should this be counted toward the initiating task? */

		task_io_account_read(rdata->got_bytes);

		cifs_stats_bytes_read(tcon, rdata->got_bytes);

		break;

	default:

		if (rdata->result != -ENODATA)