From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760137Ab3BZCW6 (ORCPT ); Mon, 25 Feb 2013 21:22:58 -0500 Received: from mailout02.c08.mtsvc.net ([205.186.168.190]:36913 "EHLO mailout02.c08.mtsvc.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760055Ab3BZCWk (ORCPT ); Mon, 25 Feb 2013 21:22:40 -0500 From: Peter Hurley To: Stanislav Kinsbursky Cc: Andrew Morton , linux-kernel@vger.kernel.org, Dave Jones , Peter Hurley Subject: [PATCH 03/10] ipc: Separate msg allocation from userspace copy Date: Mon, 25 Feb 2013 21:21:40 -0500 Message-Id: <1361845307-12737-4-git-send-email-peter@hurleysoftware.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1361845307-12737-1-git-send-email-peter@hurleysoftware.com> References: <1361845307-12737-1-git-send-email-peter@hurleysoftware.com> X-Authenticated-User: 125194 peter@hurleysoftware.com Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Separating msg allocation enables single-block vmalloc allocation instead. Signed-off-by: Peter Hurley --- ipc/msgutil.c | 52 ++++++++++++++++++++++++++++++++++++++-------------- 1 file changed, 38 insertions(+), 14 deletions(-) diff --git a/ipc/msgutil.c b/ipc/msgutil.c index 98b1c2b..0a5c8a9 100644 --- a/ipc/msgutil.c +++ b/ipc/msgutil.c @@ -44,21 +44,54 @@ struct msg_msgseg { #define DATALEN_MSG (int)(PAGE_SIZE-sizeof(struct msg_msg)) #define DATALEN_SEG (int)(PAGE_SIZE-sizeof(struct msg_msgseg)) -struct msg_msg *load_msg(const void __user *src, int len) + +static struct msg_msg *alloc_msg(int len) { struct msg_msg *msg; struct msg_msgseg **pseg; - int err; int alen; alen = min(len, DATALEN_MSG); msg = kmalloc(sizeof(*msg) + alen, GFP_KERNEL); if (msg == NULL) - return ERR_PTR(-ENOMEM); + return NULL; msg->next = NULL; msg->security = NULL; + len -= alen; + pseg = &msg->next; + while (len > 0) { + struct msg_msgseg *seg; + alen = min(len, DATALEN_SEG); + seg = kmalloc(sizeof(*seg) + alen, GFP_KERNEL); + if (seg == NULL) + goto out_err; + *pseg = seg; + seg->next = NULL; + pseg = &seg->next; + len -= alen; + } + + return msg; + +out_err: + free_msg(msg); + return NULL; +} + +struct msg_msg *load_msg(const void __user *src, int len) +{ + struct msg_msg *msg; + struct msg_msgseg *seg; + int err; + int alen; + + msg = alloc_msg(len); + if (msg == NULL) + return ERR_PTR(-ENOMEM); + + alen = min(len, DATALEN_MSG); if (copy_from_user(msg + 1, src, alen)) { err = -EFAULT; goto out_err; @@ -66,23 +99,14 @@ struct msg_msg *load_msg(const void __user *src, int len) len -= alen; src = ((char __user *)src) + alen; - pseg = &msg->next; + seg = msg->next; while (len > 0) { - struct msg_msgseg *seg; alen = min(len, DATALEN_SEG); - seg = kmalloc(sizeof(*seg) + alen, - GFP_KERNEL); - if (seg == NULL) { - err = -ENOMEM; - goto out_err; - } - *pseg = seg; - seg->next = NULL; if (copy_from_user(seg + 1, src, alen)) { err = -EFAULT; goto out_err; } - pseg = &seg->next; + seg = seg->next; len -= alen; src = ((char __user *)src) + alen; } -- 1.8.1.2