Merge tag 'for-linus-4.18' of git://github.com/cminyard/linux-ipmi

0eb00613 · Linus Torvalds <[email protected]> · 2018-06-06 15:48:10 -07:00

Pull IPMI updates from Corey Minyard:
 "It's been a busy release for the IPMI driver. Some notable changes:

   - A user was running into timeout issues doing maintenance commands
     over the IPMB network behind an IPMI controller.

     Extend the maintenance mode concept to messages over IPMB and allow
     the timeouts to be tuned.

   - Lots of cleanup, style fixing, some bugfixes, and such.

   - At least one user was having trouble with the way the IPMI driver
     would lock the i2c driver module it used.

     The IPMI driver was not designed for hotplug. However, hotplug is a
     reality now, so the IPMI driver was modified to support hotplug.

   - The proc interface code is now completely removed. Long live sysfs!"

* tag 'for-linus-4.18' of git://github.com/cminyard/linux-ipmi: (35 commits)
  ipmi: Properly release srcu locks on error conditions
  ipmi: NPCM7xx KCS BMC: enable interrupt to the host
  ipmi:bt: Set the timeout before doing a capabilities check
  ipmi: Remove the proc interface
  ipmi_ssif: Fix uninitialized variable issue
  ipmi: add an NPCM7xx KCS BMC driver
  ipmi_si: Clean up shutdown a bit
  ipmi_si: Rename intf_num to si_num
  ipmi: Remove smi->intf checks
  ipmi_ssif: Get rid of unused intf_num
  ipmi: Get rid of ipmi_user_t and ipmi_smi_t in include files
  ipmi: ipmi_unregister_smi() cannot fail, have it return void
  ipmi_devintf: Add an error return on invalid ioctls
  ipmi: Remove usecount function from interfaces
  ipmi_ssif: Remove usecount handling
  ipmi: Remove condition on interface shutdown
  ipmi_ssif: Convert over to a shutdown handler
  ipmi_si: Convert over to a shutdown handler
  ipmi: Rework locking and shutdown for hot remove
  ipmi: Fix some counter issues
  ...

Commit: 0eb0061381b2bac082cc26d573fc48fe99db3922
Parents: 84504930 · 048f7c3e

Merge commit. Changes below are compared with the first parent: 84504930.

Changes

13 files changed · +1752 −1883

File	Status	Add	Del	Content
Documentation/devicetree/bindings/ipmi/npcm7xx-kcs-bmc.txt	added	+39	−0	View file
drivers/char/ipmi/Kconfig	modified	+15	−8	View file
drivers/char/ipmi/Makefile	modified	+1	−0	View file
drivers/char/ipmi/ipmi_bt_sm.c	modified	+2	−1	View file
drivers/char/ipmi/ipmi_devintf.c	modified	+51	−78	View file
drivers/char/ipmi/ipmi_msghandler.c	modified	+1001	−1122	View file
drivers/char/ipmi/ipmi_poweroff.c	modified	+16	−16	View file
drivers/char/ipmi/ipmi_si_intf.c	modified	+30	−168	View file
drivers/char/ipmi/ipmi_ssif.c	modified	+33	−150	View file
drivers/char/ipmi/ipmi_watchdog.c	modified	+184	−223	View file
drivers/char/ipmi/kcs_bmc_npcm7xx.c	added	+215	−0	View file
include/linux/ipmi.h	modified	+96	−57	View file
include/linux/ipmi_smi.h	modified	+69	−60	View file

Only the first 600 diff lines are shown. Download the complete patch.

Documentation/devicetree/bindings/ipmi/npcm7xx-kcs-bmc.txt

View file

diff --git a/Documentation/devicetree/bindings/ipmi/npcm7xx-kcs-bmc.txt b/Documentation/devicetree/bindings/ipmi/npcm7xx-kcs-bmc.txt
new file mode 100644
index 0000000..3538a21
--- /dev/null
+++ b/Documentation/devicetree/bindings/ipmi/npcm7xx-kcs-bmc.txt
@@ -0,0 +1,39 @@
+* Nuvoton NPCM7xx KCS (Keyboard Controller Style) IPMI interface
+
+The Nuvoton SOCs (NPCM7xx) are commonly used as BMCs
+(Baseboard Management Controllers) and the KCS interface can be
+used to perform in-band IPMI communication with their host.
+
+Required properties:
+- compatible : should be one of
+    "nuvoton,npcm750-kcs-bmc"
+- interrupts : interrupt generated by the controller
+- kcs_chan : The KCS channel number in the controller
+
+Example:
+
+    lpc_kcs: lpc_kcs@f0007000 {
+        compatible = "nuvoton,npcm750-lpc-kcs", "simple-mfd", "syscon";
+        reg = <0xf0007000 0x40>;
+        reg-io-width = <1>;
+
+        #address-cells = <1>;
+        #size-cells = <1>;
+        ranges = <0x0 0xf0007000 0x40>;
+
+        kcs1: kcs1@0 {
+            compatible = "nuvoton,npcm750-kcs-bmc";
+            reg = <0x0 0x40>;
+            interrupts = <0 9 4>;
+            kcs_chan = <1>;
+            status = "disabled";
+        };
+
+        kcs2: kcs2@0 {
+            compatible = "nuvoton,npcm750-kcs-bmc";
+            reg = <0x0 0x40>;
+            interrupts = <0 9 4>;
+            kcs_chan = <2>;
+            status = "disabled";
+        };
+    };
\ No newline at end of file

drivers/char/ipmi/Kconfig

View file

diff --git a/drivers/char/ipmi/Kconfig b/drivers/char/ipmi/Kconfig
index 3bda116..c108441 100644
--- a/drivers/char/ipmi/Kconfig
+++ b/drivers/char/ipmi/Kconfig
@@ -22,14 +22,6 @@ config IPMI_DMI_DECODE
 
 if IPMI_HANDLER
 
-config IPMI_PROC_INTERFACE
-       bool 'Provide an interface for IPMI stats in /proc (deprecated)'
-       depends on PROC_FS
-       default y
-       help
-         Do not use this any more, use sysfs for this info.  It will be
-	 removed in future kernel versions.
-
 config IPMI_PANIC_EVENT
        bool 'Generate a panic event to all BMCs on a panic'
        help
@@ -111,6 +103,21 @@ config ASPEED_KCS_IPMI_BMC
 	  The driver implements the BMC side of the KCS contorller, it
 	  provides the access of KCS IO space for BMC side.
 
+config NPCM7XX_KCS_IPMI_BMC
+	depends on ARCH_NPCM7XX || COMPILE_TEST
+	select IPMI_KCS_BMC
+	select REGMAP_MMIO
+	tristate "NPCM7xx KCS IPMI BMC driver"
+	help
+	  Provides a driver for the KCS (Keyboard Controller Style) IPMI
+	  interface found on Nuvoton NPCM7xx SOCs.
+
+	  The driver implements the BMC side of the KCS contorller, it
+	  provides the access of KCS IO space for BMC side.
+
+	  This support is also available as a module.  If so, the module
+	  will be called kcs_bmc_npcm7xx.
+
 config ASPEED_BT_IPMI_BMC
 	depends on ARCH_ASPEED || COMPILE_TEST
        depends on REGMAP && REGMAP_MMIO && MFD_SYSCON

drivers/char/ipmi/Makefile

View file

diff --git a/drivers/char/ipmi/Makefile b/drivers/char/ipmi/Makefile
index 21e9e87..7a3baf3 100644
--- a/drivers/char/ipmi/Makefile
+++ b/drivers/char/ipmi/Makefile
@@ -24,3 +24,4 @@ obj-$(CONFIG_IPMI_POWEROFF) += ipmi_poweroff.o
 obj-$(CONFIG_IPMI_KCS_BMC) += kcs_bmc.o
 obj-$(CONFIG_ASPEED_BT_IPMI_BMC) += bt-bmc.o
 obj-$(CONFIG_ASPEED_KCS_IPMI_BMC) += kcs_bmc_aspeed.o
+obj-$(CONFIG_NPCM7XX_KCS_IPMI_BMC) += kcs_bmc_npcm7xx.o

drivers/char/ipmi/ipmi_bt_sm.c

View file

diff --git a/drivers/char/ipmi/ipmi_bt_sm.c b/drivers/char/ipmi/ipmi_bt_sm.c
index fd4ea8d..a339766 100644
--- a/drivers/char/ipmi/ipmi_bt_sm.c
+++ b/drivers/char/ipmi/ipmi_bt_sm.c
@@ -504,11 +504,12 @@ static enum si_sm_result bt_event(struct si_sm_data *bt, long time)
 		if (status & BT_H_BUSY)		/* clear a leftover H_BUSY */
 			BT_CONTROL(BT_H_BUSY);
 
+		bt->timeout = bt->BT_CAP_req2rsp;
+
 		/* Read BT capabilities if it hasn't been done yet */
 		if (!bt->BT_CAP_outreqs)
 			BT_STATE_CHANGE(BT_STATE_CAPABILITIES_BEGIN,
 					SI_SM_CALL_WITHOUT_DELAY);
-		bt->timeout = bt->BT_CAP_req2rsp;
 		BT_SI_SM_RETURN(SI_SM_IDLE);
 
 	case BT_STATE_XACTION_START:

drivers/char/ipmi/ipmi_devintf.c

View file

diff --git a/drivers/char/ipmi/ipmi_devintf.c b/drivers/char/ipmi/ipmi_devintf.c
index 8ecfd47..1a486ae 100644
--- a/drivers/char/ipmi/ipmi_devintf.c
+++ b/drivers/char/ipmi/ipmi_devintf.c
@@ -26,7 +26,7 @@
 
 struct ipmi_file_private
 {
-	ipmi_user_t          user;
+	struct ipmi_user     *user;
 	spinlock_t           recv_msg_lock;
 	struct list_head     recv_msgs;
 	struct file          *file;
@@ -37,7 +37,6 @@ struct ipmi_file_private
 	unsigned int         default_retry_time_ms;
 };
 
-static DEFINE_MUTEX(ipmi_mutex);
 static void file_receive_handler(struct ipmi_recv_msg *msg,
 				 void                 *handler_data)
 {
@@ -45,17 +44,15 @@ static void file_receive_handler(struct ipmi_recv_msg *msg,
 	int                      was_empty;
 	unsigned long            flags;
 
-	spin_lock_irqsave(&(priv->recv_msg_lock), flags);
-
-	was_empty = list_empty(&(priv->recv_msgs));
-	list_add_tail(&(msg->link), &(priv->recv_msgs));
+	spin_lock_irqsave(&priv->recv_msg_lock, flags);
+	was_empty = list_empty(&priv->recv_msgs);
+	list_add_tail(&msg->link, &priv->recv_msgs);
+	spin_unlock_irqrestore(&priv->recv_msg_lock, flags);
 
 	if (was_empty) {
 		wake_up_interruptible(&priv->wait);
 		kill_fasync(&priv->fasync_queue, SIGIO, POLL_IN);
 	}
-
-	spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
 }
 
 static __poll_t ipmi_poll(struct file *file, poll_table *wait)
@@ -68,7 +65,7 @@ static __poll_t ipmi_poll(struct file *file, poll_table *wait)
 
 	spin_lock_irqsave(&priv->recv_msg_lock, flags);
 
-	if (!list_empty(&(priv->recv_msgs)))
+	if (!list_empty(&priv->recv_msgs))
 		mask |= (EPOLLIN | EPOLLRDNORM);
 
 	spin_unlock_irqrestore(&priv->recv_msg_lock, flags);
@@ -79,13 +76,8 @@ static __poll_t ipmi_poll(struct file *file, poll_table *wait)
 static int ipmi_fasync(int fd, struct file *file, int on)
 {
 	struct ipmi_file_private *priv = file->private_data;
-	int                      result;
 
-	mutex_lock(&ipmi_mutex); /* could race against open() otherwise */
-	result = fasync_helper(fd, file, on, &priv->fasync_queue);
-	mutex_unlock(&ipmi_mutex);
-
-	return (result);
+	return fasync_helper(fd, file, on, &priv->fasync_queue);
 }
 
 static const struct ipmi_user_hndl ipmi_hndlrs =
@@ -99,18 +91,16 @@ static int ipmi_open(struct inode *inode, struct file *file)
 	int                      rv;
 	struct ipmi_file_private *priv;
 
-
 	priv = kmalloc(sizeof(*priv), GFP_KERNEL);
 	if (!priv)
 		return -ENOMEM;
 
-	mutex_lock(&ipmi_mutex);
 	priv->file = file;
 
 	rv = ipmi_create_user(if_num,
 			      &ipmi_hndlrs,
 			      priv,
-			      &(priv->user));
+			      &priv->user);
 	if (rv) {
 		kfree(priv);
 		goto out;
@@ -118,8 +108,8 @@ static int ipmi_open(struct inode *inode, struct file *file)
 
 	file->private_data = priv;
 
-	spin_lock_init(&(priv->recv_msg_lock));
-	INIT_LIST_HEAD(&(priv->recv_msgs));
+	spin_lock_init(&priv->recv_msg_lock);
+	INIT_LIST_HEAD(&priv->recv_msgs);
 	init_waitqueue_head(&priv->wait);
 	priv->fasync_queue = NULL;
 	mutex_init(&priv->recv_mutex);
@@ -129,7 +119,6 @@ static int ipmi_open(struct inode *inode, struct file *file)
 	priv->default_retry_time_ms = 0;
 
 out:
-	mutex_unlock(&ipmi_mutex);
 	return rv;
 }
 
@@ -137,7 +126,7 @@ static int ipmi_release(struct inode *inode, struct file *file)
 {
 	struct ipmi_file_private *priv = file->private_data;
 	int                      rv;
-	struct  ipmi_recv_msg *msg, *next;
+	struct ipmi_recv_msg *msg, *next;
 
 	rv = ipmi_destroy_user(priv->user);
 	if (rv)
@@ -146,13 +135,12 @@ static int ipmi_release(struct inode *inode, struct file *file)
 	list_for_each_entry_safe(msg, next, &priv->recv_msgs, link)
 		ipmi_free_recv_msg(msg);
 
-
 	kfree(priv);
 
 	return 0;
 }
 
-static int handle_send_req(ipmi_user_t     user,
+static int handle_send_req(struct ipmi_user *user,
 			   struct ipmi_req *req,
 			   int             retries,
 			   unsigned int    retry_time_ms)
@@ -189,8 +177,7 @@ static int handle_send_req(ipmi_user_t     user,
 
 		if (copy_from_user(msg.data,
 				   req->msg.data,
-				   req->msg.data_len))
-		{
+				   req->msg.data_len)) {
 			rv = -EFAULT;
 			goto out;
 		}
@@ -233,25 +220,24 @@ static int handle_recv(struct ipmi_file_private *priv,
 	mutex_lock(&priv->recv_mutex);
 
 	/* Grab the message off the list. */
-	spin_lock_irqsave(&(priv->recv_msg_lock), flags);
+	spin_lock_irqsave(&priv->recv_msg_lock, flags);
 	if (list_empty(&(priv->recv_msgs))) {
-		spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
+		spin_unlock_irqrestore(&priv->recv_msg_lock, flags);
 		rv = -EAGAIN;
 		goto recv_err;
 	}
 	entry = priv->recv_msgs.next;
 	msg = list_entry(entry, struct ipmi_recv_msg, link);
 	list_del(entry);
-	spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
+	spin_unlock_irqrestore(&priv->recv_msg_lock, flags);
 
 	addr_len = ipmi_addr_length(msg->addr.addr_type);
-	if (rsp->addr_len < addr_len)
-	{
+	if (rsp->addr_len < addr_len) {
 		rv = -EINVAL;
 		goto recv_putback_on_err;
 	}
 
-	if (copy_to_user(rsp->addr, &(msg->addr), addr_len)) {
+	if (copy_to_user(rsp->addr, &msg->addr, addr_len)) {
 		rv = -EFAULT;
 		goto recv_putback_on_err;
 	}
@@ -273,8 +259,7 @@ static int handle_recv(struct ipmi_file_private *priv,
 
 		if (copy_to_user(rsp->msg.data,
 				 msg->msg.data,
-				 msg->msg.data_len))
-		{
+				 msg->msg.data_len)) {
 			rv = -EFAULT;
 			goto recv_putback_on_err;
 		}
@@ -294,9 +279,9 @@ static int handle_recv(struct ipmi_file_private *priv,
 recv_putback_on_err:
 	/* If we got an error, put the message back onto
 	   the head of the queue. */
-	spin_lock_irqsave(&(priv->recv_msg_lock), flags);
-	list_add(entry, &(priv->recv_msgs));
-	spin_unlock_irqrestore(&(priv->recv_msg_lock), flags);
+	spin_lock_irqsave(&priv->recv_msg_lock, flags);
+	list_add(entry, &priv->recv_msgs);
+	spin_unlock_irqrestore(&priv->recv_msg_lock, flags);
 recv_err:
 	mutex_unlock(&priv->recv_mutex);
 	return rv;
@@ -307,9 +292,9 @@ static int copyout_recv(struct ipmi_recv *rsp, void __user *to)
 	return copy_to_user(to, rsp, sizeof(struct ipmi_recv)) ? -EFAULT : 0;
 }
 
-static int ipmi_ioctl(struct file   *file,
-		      unsigned int  cmd,
-		      unsigned long data)
+static long ipmi_ioctl(struct file   *file,
+		       unsigned int  cmd,
+		       unsigned long data)
 {
 	int                      rv = -EINVAL;
 	struct ipmi_file_private *priv = file->private_data;
@@ -320,16 +305,20 @@ static int ipmi_ioctl(struct file   *file,
 	case IPMICTL_SEND_COMMAND:
 	{
 		struct ipmi_req req;
+		int retries;
+		unsigned int retry_time_ms;
 
 		if (copy_from_user(&req, arg, sizeof(req))) {
 			rv = -EFAULT;
 			break;
 		}
 
-		rv = handle_send_req(priv->user,
-				     &req,
-				     priv->default_retries,
-				     priv->default_retry_time_ms);
+		mutex_lock(&priv->recv_mutex);
+		retries = priv->default_retries;
+		retry_time_ms = priv->default_retry_time_ms;
+		mutex_unlock(&priv->recv_mutex);
+
+		rv = handle_send_req(priv->user, &req, retries, retry_time_ms);
 		break;
 	}
 
@@ -569,8 +558,10 @@ static int ipmi_ioctl(struct file   *file,
 			break;
 		}
 
+		mutex_lock(&priv->recv_mutex);
 		priv->default_retries = parms.retries;
 		priv->default_retry_time_ms = parms.retry_time_ms;
+		mutex_unlock(&priv->recv_mutex);
 		rv = 0;
 		break;
 	}
@@ -579,8 +570,10 @@ static int ipmi_ioctl(struct file   *file,
 	{
 		struct ipmi_timing_parms parms;
 
+		mutex_lock(&priv->recv_mutex);
 		parms.retries = priv->default_retries;
 		parms.retry_time_ms = priv->default_retry_time_ms;
+		mutex_unlock(&priv->recv_mutex);
 
 		if (copy_to_user(arg, &parms, sizeof(parms))) {
 			rv = -EFAULT;
@@ -615,30 +608,16 @@ static int ipmi_ioctl(struct file   *file,
 		rv = ipmi_set_maintenance_mode(priv->user, mode);
 		break;
 	}
+
+	default:
+		rv = -ENOTTY;
+		break;
 	}
   
 	return rv;
 }
 
-/*
- * Note: it doesn't make sense to take the BKL here but
- *       not in compat_ipmi_ioctl. -arnd
- */
-static long ipmi_unlocked_ioctl(struct file   *file,
-			        unsigned int  cmd,
-			        unsigned long data)
-{
-	int ret;
-
-	mutex_lock(&ipmi_mutex);
-	ret = ipmi_ioctl(file, cmd, data);
-	mutex_unlock(&ipmi_mutex);
-
-	return ret;
-}
-
 #ifdef CONFIG_COMPAT
-
 /*
  * The following code contains code for supporting 32-bit compatible
  * ioctls on 64-bit kernels.  This allows running 32-bit apps on the
@@ -749,15 +728,21 @@ static long compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
 	{
 		struct ipmi_req	rp;
 		struct compat_ipmi_req r32;
+		int retries;
+		unsigned int retry_time_ms;
 
 		if (copy_from_user(&r32, compat_ptr(arg), sizeof(r32)))
 			return -EFAULT;
 
 		get_compat_ipmi_req(&rp, &r32);
 
+		mutex_lock(&priv->recv_mutex);
+		retries = priv->default_retries;
+		retry_time_ms = priv->default_retry_time_ms;
+		mutex_unlock(&priv->recv_mutex);
+
 		return handle_send_req(priv->user, &rp,
-				priv->default_retries,
-				priv->default_retry_time_ms);
+				       retries, retry_time_ms);
 	}
 	case COMPAT_IPMICTL_SEND_COMMAND_SETTIME:
 	{
@@ -791,25 +776,13 @@ static long compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
 		return ipmi_ioctl(filep, cmd, arg);
 	}
 }
-
-static long unlocked_compat_ipmi_ioctl(struct file *filep, unsigned int cmd,
-				       unsigned long arg)
-{
-	int ret;
-
-	mutex_lock(&ipmi_mutex);
-	ret = compat_ipmi_ioctl(filep, cmd, arg);
-	mutex_unlock(&ipmi_mutex);
-
-	return ret;
-}
 #endif
 
 static const struct file_operations ipmi_fops = {
 	.owner		= THIS_MODULE,
-	.unlocked_ioctl	= ipmi_unlocked_ioctl,
+	.unlocked_ioctl	= ipmi_ioctl,
 #ifdef CONFIG_COMPAT
-	.compat_ioctl   = unlocked_compat_ipmi_ioctl,
+	.compat_ioctl   = compat_ipmi_ioctl,
 #endif
 	.open		= ipmi_open,
 	.release	= ipmi_release,

drivers/char/ipmi/ipmi_msghandler.c

View file

diff --git a/drivers/char/ipmi/ipmi_msghandler.c b/drivers/char/ipmi/ipmi_msghandler.c
index 3611489..51832b8 100644
--- a/drivers/char/ipmi/ipmi_msghandler.c
+++ b/drivers/char/ipmi/ipmi_msghandler.c
@@ -37,11 +37,30 @@
 static struct ipmi_recv_msg *ipmi_alloc_recv_msg(void);
 static int ipmi_init_msghandler(void);
 static void smi_recv_tasklet(unsigned long);
-static void handle_new_recv_msgs(ipmi_smi_t intf);
-static void need_waiter(ipmi_smi_t intf);
-static int handle_one_recv_msg(ipmi_smi_t          intf,
+static void handle_new_recv_msgs(struct ipmi_smi *intf);
+static void need_waiter(struct ipmi_smi *intf);
+static int handle_one_recv_msg(struct ipmi_smi *intf,
 			       struct ipmi_smi_msg *msg);
 
+#ifdef DEBUG
+static void ipmi_debug_msg(const char *title, unsigned char *data,
+			   unsigned int len)
+{
+	int i, pos;
+	char buf[100];
+
+	pos = snprintf(buf, sizeof(buf), "%s: ", title);
+	for (i = 0; i < len; i++)
+		pos += snprintf(buf + pos, sizeof(buf) - pos,
+				" %2.2x", data[i]);
+	pr_debug("%s\n", buf);
+}
+#else
+static void ipmi_debug_msg(const char *title, unsigned char *data,
+			   unsigned int len)
+{ }
+#endif
+
 static int initialized;
 
 enum ipmi_panic_event_op {
@@ -112,14 +131,13 @@ module_param_cb(panic_op, &panic_op_ops, NULL, 0600);
 MODULE_PARM_DESC(panic_op, "Sets if the IPMI driver will attempt to store panic information in the event log in the event of a panic.  Set to 'none' for no, 'event' for a single event, or 'string' for a generic event and the panic string in IPMI OEM events.");
 
 
-#ifdef CONFIG_IPMI_PROC_INTERFACE
-static struct proc_dir_entry *proc_ipmi_root;
-#endif /* CONFIG_IPMI_PROC_INTERFACE */
+#define MAX_EVENTS_IN_QUEUE	25
 
 /* Remain in auto-maintenance mode for this amount of time (in ms). */
-#define IPMI_MAINTENANCE_MODE_TIMEOUT 30000
-
-#define MAX_EVENTS_IN_QUEUE	25
+static unsigned long maintenance_mode_timeout_ms = 30000;
+module_param(maintenance_mode_timeout_ms, ulong, 0644);
+MODULE_PARM_DESC(maintenance_mode_timeout_ms,
+		 "The time (milliseconds) after the last maintenance message that the connection stays in maintenance mode.");
 
 /*
  * Don't let a message sit in a queue forever, always time it with at lest
@@ -127,6 +145,31 @@ static struct proc_dir_entry *proc_ipmi_root;
  */
 #define MAX_MSG_TIMEOUT		60000
 
+/*
+ * Timeout times below are in milliseconds, and are done off a 1
+ * second timer.  So setting the value to 1000 would mean anything
+ * between 0 and 1000ms.  So really the only reasonable minimum
+ * setting it 2000ms, which is between 1 and 2 seconds.
+ */
+
+/* The default timeout for message retries. */
+static unsigned long default_retry_ms = 2000;
+module_param(default_retry_ms, ulong, 0644);
+MODULE_PARM_DESC(default_retry_ms,
+		 "The time (milliseconds) between retry sends");
+
+/* The default timeout for maintenance mode message retries. */
+static unsigned long default_maintenance_retry_ms = 3000;
+module_param(default_maintenance_retry_ms, ulong, 0644);
+MODULE_PARM_DESC(default_maintenance_retry_ms,
+		 "The time (milliseconds) between retry sends in maintenance mode");
+
+/* The default maximum number of retries */
+static unsigned int default_max_retries = 4;
+module_param(default_max_retries, uint, 0644);
+MODULE_PARM_DESC(default_max_retries,
+		 "The time (milliseconds) between retry sends in maintenance mode");
+
 /* Call every ~1000 ms. */
 #define IPMI_TIMEOUT_TIME	1000
 
@@ -150,8 +193,12 @@ static struct proc_dir_entry *proc_ipmi_root;
 struct ipmi_user {
 	struct list_head link;
 
-	/* Set to false when the user is destroyed. */
-	bool valid;
+	/*
+	 * Set to NULL when the user is destroyed, a pointer to myself
+	 * so srcu_dereference can be used on it.
+	 */
+	struct ipmi_user *self;
+	struct srcu_struct release_barrier;
 
 	struct kref refcount;
 
@@ -160,16 +207,33 @@ struct ipmi_user {
 	void             *handler_data;
 
 	/* The interface this user is bound to. */
-	ipmi_smi_t intf;
+	struct ipmi_smi *intf;
 
 	/* Does this interface receive IPMI events? */
 	bool gets_events;
 };
 
+static struct ipmi_user *acquire_ipmi_user(struct ipmi_user *user, int *index)
+	__acquires(user->release_barrier)
+{
+	struct ipmi_user *ruser;
+
+	*index = srcu_read_lock(&user->release_barrier);
+	ruser = srcu_dereference(user->self, &user->release_barrier);
+	if (!ruser)
+		srcu_read_unlock(&user->release_barrier, *index);
+	return ruser;
+}
+
+static void release_ipmi_user(struct ipmi_user *user, int index)
+{
+	srcu_read_unlock(&user->release_barrier, index);
+}
+
 struct cmd_rcvr {
 	struct list_head link;
 
-	ipmi_user_t   user;
+	struct ipmi_user *user;
 	unsigned char netfn;
 	unsigned char cmd;
 	unsigned int  chans;
@@ -247,13 +311,6 @@ struct ipmi_my_addrinfo {
 	unsigned char lun;
 };
 