From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758639Ab2KVWjY (ORCPT ); Thu, 22 Nov 2012 17:39:24 -0500 Received: from mail.kernel.org ([198.145.19.201]:49023 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753550Ab2KVSdl (ORCPT ); Thu, 22 Nov 2012 13:33:41 -0500 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: Greg Kroah-Hartman , alan@lxorguk.ukuu.org.uk, Sage Weil , Alex Elder Subject: [ 159/171] libceph: change ceph_con_in_msg_alloc convention to be less weird Date: Wed, 21 Nov 2012 16:41:45 -0800 Message-Id: <20121122004049.307758673@linuxfoundation.org> X-Mailer: git-send-email 1.8.0.197.g5a90748 In-Reply-To: <20121122004033.298367941@linuxfoundation.org> References: <20121122004033.298367941@linuxfoundation.org> User-Agent: quilt/0.60-2.1.2 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sage Weil (cherry picked from commit 4740a623d20c51d167da7f752b63e2b8714b2543) This function's calling convention is very limiting. In particular, we can't return any error other than ENOMEM (and only implicitly), which is a problem (see next patch). Instead, return an normal 0 or error code, and make the skip a pointer output parameter. Drop the useless in_hdr argument (we have the con pointer). Signed-off-by: Sage Weil Reviewed-by: Alex Elder Signed-off-by: Greg Kroah-Hartman --- net/ceph/messenger.c | 56 ++++++++++++++++++++++++++++----------------------- 1 file changed, 31 insertions(+), 25 deletions(-) --- a/net/ceph/messenger.c +++ b/net/ceph/messenger.c @@ -1733,9 +1733,7 @@ static int read_partial_message_section( return 1; } -static bool ceph_con_in_msg_alloc(struct ceph_connection *con, - struct ceph_msg_header *hdr); - +static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip); static int read_partial_message_pages(struct ceph_connection *con, struct page **pages, @@ -1864,9 +1862,14 @@ static int read_partial_message(struct c /* allocate message? */ if (!con->in_msg) { + int skip = 0; + dout("got hdr type %d front %d data %d\n", con->in_hdr.type, con->in_hdr.front_len, con->in_hdr.data_len); - if (ceph_con_in_msg_alloc(con, &con->in_hdr)) { + ret = ceph_con_in_msg_alloc(con, &skip); + if (ret < 0) + return ret; + if (skip) { /* skip this message */ dout("alloc_msg said skip message\n"); BUG_ON(con->in_msg); @@ -1876,12 +1879,8 @@ static int read_partial_message(struct c con->in_seq++; return 0; } - if (!con->in_msg) { - con->error_msg = - "error allocating memory for incoming message"; - return -ENOMEM; - } + BUG_ON(!con->in_msg); BUG_ON(con->in_msg->con != con); m = con->in_msg; m->front.iov_len = 0; /* haven't read it yet */ @@ -2715,43 +2714,50 @@ static int ceph_alloc_middle(struct ceph * connection, and save the result in con->in_msg. Uses the * connection's private alloc_msg op if available. * - * Returns true if the message should be skipped, false otherwise. - * If true is returned (skip message), con->in_msg will be NULL. - * If false is returned, con->in_msg will contain a pointer to the - * newly-allocated message, or NULL in case of memory exhaustion. + * Returns 0 on success, or a negative error code. + * + * On success, if we set *skip = 1: + * - the next message should be skipped and ignored. + * - con->in_msg == NULL + * or if we set *skip = 0: + * - con->in_msg is non-null. + * On error (ENOMEM, EAGAIN, ...), + * - con->in_msg == NULL */ -static bool ceph_con_in_msg_alloc(struct ceph_connection *con, - struct ceph_msg_header *hdr) +static int ceph_con_in_msg_alloc(struct ceph_connection *con, int *skip) { + struct ceph_msg_header *hdr = &con->in_hdr; int type = le16_to_cpu(hdr->type); int front_len = le32_to_cpu(hdr->front_len); int middle_len = le32_to_cpu(hdr->middle_len); - int ret; + int ret = 0; BUG_ON(con->in_msg != NULL); if (con->ops->alloc_msg) { - int skip = 0; - mutex_unlock(&con->mutex); - con->in_msg = con->ops->alloc_msg(con, hdr, &skip); + con->in_msg = con->ops->alloc_msg(con, hdr, skip); mutex_lock(&con->mutex); if (con->in_msg) { con->in_msg->con = con->ops->get(con); BUG_ON(con->in_msg->con == NULL); } - if (skip) + if (*skip) { con->in_msg = NULL; - - if (!con->in_msg) - return skip != 0; + return 0; + } + if (!con->in_msg) { + con->error_msg = + "error allocating memory for incoming message"; + return -ENOMEM; + } } if (!con->in_msg) { con->in_msg = ceph_msg_new(type, front_len, GFP_NOFS, false); if (!con->in_msg) { pr_err("unable to allocate msg type %d len %d\n", type, front_len); - return false; + return -ENOMEM; } con->in_msg->con = con->ops->get(con); BUG_ON(con->in_msg->con == NULL); @@ -2767,7 +2773,7 @@ static bool ceph_con_in_msg_alloc(struct } } - return false; + return ret; }