[2.6.23 PATCH 13/18] dm: netlink

Alasdair G Kergon
2007-07-11T21:04:15Z

From: Mike Anderson <andmike@us.ibm.com>

This patch adds a dm-netlink skeleton support to the Makefile, and the dm
directory.

Signed-off-by: Mike Anderson <andmike@us.ibm.com>
Signed-off-by: Alasdair G Kergon <agk@redhat.com>
---

drivers/md/Kconfig | 5 ++
drivers/md/Makefile | 4 +
drivers/md/dm-netlink.c | 103 ++++++++++++++++++++++++++++++++++++++++++++++++
drivers/md/dm-netlink.h | 50 +++++++++++++++++++++++
drivers/md/dm.c | 3 +
include/linux/netlink.h | 2
6 files changed, 166 insertions(+), 1 deletion(-)

Index: linux/drivers/md/Kconfig
===================================================================
--- linux.orig/drivers/md/Kconfig 2007-07-11 21:37:31.000000000 +0100
+++ linux/drivers/md/Kconfig 2007-07-11 21:37:50.000000000 +0100
@@ -271,6 +271,11 @@ config DM_DELAY

If unsure, say N.

+config DM_NETLINK
+ bool "DM netlink events (EXPERIMENTAL)"
+ depends on BLK_DEV_DM && EXPERIMENTAL
+ ---help---
+ Generate netlink events for DM events.
endmenu

endif
Index: linux/drivers/md/Makefile
===================================================================
--- linux.orig/drivers/md/Makefile 2007-07-11 21:37:31.000000000 +0100
+++ linux/drivers/md/Makefile 2007-07-11 21:37:50.000000000 +0100
@@ -46,6 +46,10 @@ ifeq ($(CONFIG_ALTIVEC),y)
altivec_flags := -maltivec -mabi=altivec
endif

+ifeq ($(CONFIG_DM_NETLINK),y)
+dm-mod-objs += dm-netlink.o
+endif
+
targets += raid6int1.c
$(obj)/raid6int1.c: UNROLL := 1
$(obj)/raid6int1.c: $(src)/raid6int.uc $(src)/unroll.pl FORCE
Index: linux/drivers/md/dm-netlink.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux/drivers/md/dm-netlink.c 2007-07-11 21:37:50.000000000 +0100
@@ -0,0 +1,103 @@
+/*
+ * Device Mapper Netlink Support (dm-netlink)
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2005, 2006
+ * Author: Mike Anderson <andmike@us.ibm.com>
+ */
+#include <linux/module.h>
+#include <linux/mempool.h>
+#include <linux/time.h>
+#include <linux/jiffies.h>
+#include <linux/security.h>
+#include <net/sock.h>
+#include <net/netlink.h>
+
+#include "dm.h"
+#include "dm-netlink.h"
+
+#define DM_MSG_PREFIX "netlink"
+
+#define DM_EVENT_SKB_SIZE NLMSG_GOODSIZE
+
+struct dm_event_cache {
+ struct kmem_cache *cache;
+ unsigned skb_size;
+};
+
+static struct dm_event_cache _dme_cache;
+
+static int dme_cache_init(struct dm_event_cache *dc, unsigned skb_size)
+{
+ dc->skb_size = skb_size;
+
+ dc->cache = KMEM_CACHE(dm_event, 0);
+ if (!dc->cache)
+ return -ENOMEM;
+
+ return 0;
+}
+
+static void dme_cache_destroy(struct dm_event_cache *dc)
+{
+ kmem_cache_destroy(dc->cache);
+}
+
+static void dme_cache_event_put(struct dm_event *evt)
+{
+ struct dm_event_cache *dc = evt->cdata;
+
+ kmem_cache_free(dc->cache, evt);
+}
+
+static struct dm_event *dme_cache_event_get(struct dm_event_cache *dc,
+ struct mapped_device *md)
+{
+ struct dm_event *evt;
+
+ evt = kmem_cache_alloc(dc->cache, GFP_ATOMIC);
+ if (!evt)
+ return NULL;
+
+ INIT_LIST_HEAD(&evt->elist);
+ evt->cdata = dc;
+ evt->md = md;
+ evt->skb = alloc_skb(dc->skb_size, GFP_ATOMIC);
+ if (!evt->skb)
+ goto cache_err;
+
+ return evt;
+
+cache_err:
+ dme_cache_event_put(evt);
+ return NULL;
+}
+
+int __init dm_netlink_init(void)
+{
+ int r;
+
+ r = dme_cache_init(&_dme_cache, DM_EVENT_SKB_SIZE);
+ if (!r)
+ DMINFO("version 1.0.0 loaded");
+
+ return r;
+}
+
+void dm_netlink_exit(void)
+{
+ dme_cache_destroy(&_dme_cache);
+}
Index: linux/drivers/md/dm-netlink.h
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux/drivers/md/dm-netlink.h 2007-07-11 21:37:50.000000000 +0100
@@ -0,0 +1,50 @@
+/*
+ * Device Mapper Netlink Support
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ *
+ * Copyright IBM Corporation, 2005, 2006
+ * Author: Mike Anderson <andmike@us.ibm.com>
+ */
+#ifndef DM_NETLINK_H
+#define DM_NETLINK_H
+
+struct dm_event_cache;
+struct mapped_device;
+struct dm_event {
+ struct dm_event_cache *cdata;
+ struct mapped_device *md;
+ struct sk_buff *skb;
+ struct list_head elist;
+};
+
+#ifdef CONFIG_DM_NETLINK
+
+int dm_netlink_init(void);
+void dm_netlink_exit(void);
+
+#else /* CONFIG_DM_NETLINK */
+
+static inline int __init dm_netlink_init(void)
+{
+ return 0;
+}
+static inline void dm_netlink_exit(void)
+{
+}
+
+#endif /* CONFIG_DM_NETLINK */
+
+#endif /* DM_NETLINK_H */
Index: linux/drivers/md/dm.c
===================================================================
--- linux.orig/drivers/md/dm.c 2007-07-11 21:37:47.000000000 +0100
+++ linux/drivers/md/dm.c 2007-07-11 21:37:50.000000000 +0100
@@ -7,6 +7,7 @@

#include "dm.h"
#include "dm-bio-list.h"
+#include "dm-netlink.h"

#include <linux/init.h>
#include <linux/module.h>
@@ -176,6 +177,7 @@ int (*_inits[])(void) __initdata = {
dm_linear_init,
dm_stripe_init,
dm_interface_init,
+ dm_netlink_init,
};

void (*_exits[])(void) = {
@@ -184,6 +186,7 @@ void (*_exits[])(void) = {
dm_linear_exit,
dm_stripe_exit,
dm_interface_exit,
+ dm_netlink_exit,
};

static int __init dm_init(void)
Index: linux/include/linux/netlink.h
===================================================================
--- linux.orig/include/linux/netlink.h 2007-07-11 21:37:31.000000000 +0100
+++ linux/include/linux/netlink.h 2007-07-11 21:37:50.000000000 +0100
@@ -21,7 +21,7 @@
#define NETLINK_DNRTMSG 14 /* DECnet routing messages */
#define NETLINK_KOBJECT_UEVENT 15 /* Kernel messages to userspace */
#define NETLINK_GENERIC 16
-/* leave room for NETLINK_DM (DM Events) */
+#define NETLINK_DM 17 /* Device Mapper */
#define NETLINK_SCSITRANSPORT 18 /* SCSI Transports */
#define NETLINK_ECRYPTFS 19