Merge branch 'linus' into cpus4096

Conflicts:

	drivers/acpi/processor_throttling.c

Signed-off-by: Ingo Molnar <mingo@elte.hu>

9 files changed, 558 insertions, 154 deletions

diff --git a/drivers/char/Kconfig b/drivers/char/Kconfig
index 2d854bb9373..650e6b44ce6 100644
--- a/drivers/char/Kconfig
+++ b/drivers/char/Kconfig
@@ -649,6 +649,14 @@ config HVCS
 	  which will also be compiled when this driver is built as a
 	  module.
 
+config IBM_BSR
+	tristate "IBM POWER Barrier Synchronization Register support"
+	depends on PPC_PSERIES
+	help
+	  This devices exposes a hardware mechanism for fast synchronization
+	  of threads across a large system which avoids bouncing a cacheline
+	  between several cores on a system
+
 source "drivers/char/ipmi/Kconfig"
 
 config DS1620
diff --git a/drivers/char/Makefile b/drivers/char/Makefile
index 81630a68475..0e0d12a0646 100644
--- a/drivers/char/Makefile
+++ b/drivers/char/Makefile
@@ -57,6 +57,7 @@ obj-$(CONFIG_MMTIMER)		+= mmtimer.o
 obj-$(CONFIG_VIOCONS)		+= viocons.o
 obj-$(CONFIG_VIOTAPE)		+= viotape.o
 obj-$(CONFIG_HVCS)		+= hvcs.o
+obj-$(CONFIG_IBM_BSR)		+= bsr.o
 obj-$(CONFIG_SGI_MBCS)		+= mbcs.o
 obj-$(CONFIG_BRIQ_PANEL)	+= briq_panel.o
 obj-$(CONFIG_BFIN_OTP)		+= bfin-otp.o
diff --git a/drivers/char/apm-emulation.c b/drivers/char/apm-emulation.c
index da8a1658a27..aaca40283be 100644
--- a/drivers/char/apm-emulation.c
+++ b/drivers/char/apm-emulation.c
@@ -59,6 +59,55 @@ struct apm_queue {
 };
 
 /*
+ * thread states (for threads using a writable /dev/apm_bios fd):
+ *
+ * SUSPEND_NONE:	nothing happening
+ * SUSPEND_PENDING:	suspend event queued for thread and pending to be read
+ * SUSPEND_READ:	suspend event read, pending acknowledgement
+ * SUSPEND_ACKED:	acknowledgement received from thread (via ioctl),
+ *			waiting for resume
+ * SUSPEND_ACKTO:	acknowledgement timeout
+ * SUSPEND_DONE:	thread had acked suspend and is now notified of
+ *			resume
+ *
+ * SUSPEND_WAIT:	this thread invoked suspend and is waiting for resume
+ *
+ * A thread migrates in one of three paths:
+ *	NONE -1-> PENDING -2-> READ -3-> ACKED -4-> DONE -5-> NONE
+ *				    -6-> ACKTO -7-> NONE
+ *	NONE -8-> WAIT -9-> NONE
+ *
+ * While in PENDING or READ, the thread is accounted for in the
+ * suspend_acks_pending counter.
+ *
+ * The transitions are invoked as follows:
+ *	1: suspend event is signalled from the core PM code
+ *	2: the suspend event is read from the fd by the userspace thread
+ *	3: userspace thread issues the APM_IOC_SUSPEND ioctl (as ack)
+ *	4: core PM code signals that we have resumed
+ *	5: APM_IOC_SUSPEND ioctl returns
+ *
+ *	6: the notifier invoked from the core PM code timed out waiting
+ *	   for all relevant threds to enter ACKED state and puts those
+ *	   that haven't into ACKTO
+ *	7: those threads issue APM_IOC_SUSPEND ioctl too late,
+ *	   get an error
+ *
+ *	8: userspace thread issues the APM_IOC_SUSPEND ioctl (to suspend),
+ *	   ioctl code invokes pm_suspend()
+ *	9: pm_suspend() returns indicating resume
+ */
+enum apm_suspend_state {
+	SUSPEND_NONE,
+	SUSPEND_PENDING,
+	SUSPEND_READ,
+	SUSPEND_ACKED,
+	SUSPEND_ACKTO,
+	SUSPEND_WAIT,
+	SUSPEND_DONE,
+};
+
+/*
  * The per-file APM data
  */
 struct apm_user {
@@ -69,13 +118,7 @@ struct apm_user {
 	unsigned int		reader: 1;
 
 	int			suspend_result;
-	unsigned int		suspend_state;
-#define SUSPEND_NONE	0		/* no suspend pending */
-#define SUSPEND_PENDING	1		/* suspend pending read */
-#define SUSPEND_READ	2		/* suspend read, pending ack */
-#define SUSPEND_ACKED	3		/* suspend acked */
-#define SUSPEND_WAIT	4		/* waiting for suspend */
-#define SUSPEND_DONE	5		/* suspend completed */
+	enum apm_suspend_state	suspend_state;
 
 	struct apm_queue	queue;
 };
@@ -83,7 +126,8 @@ struct apm_user {
 /*
  * Local variables
  */
-static int suspends_pending;
+static atomic_t suspend_acks_pending = ATOMIC_INIT(0);
+static atomic_t userspace_notification_inhibit = ATOMIC_INIT(0);
 static int apm_disabled;
 static struct task_struct *kapmd_tsk;
 
@@ -166,78 +210,6 @@ static void queue_event(apm_event_t event)
 	wake_up_interruptible(&apm_waitqueue);
 }
 
-/*
- * queue_suspend_event - queue an APM suspend event.
- *
- * Check that we're in a state where we can suspend.  If not,
- * return -EBUSY.  Otherwise, queue an event to all "writer"
- * users.  If there are no "writer" users, return '1' to
- * indicate that we can immediately suspend.
- */
-static int queue_suspend_event(apm_event_t event, struct apm_user *sender)
-{
-	struct apm_user *as;
-	int ret = 1;
-
-	mutex_lock(&state_lock);
-	down_read(&user_list_lock);
-
-	/*
-	 * If a thread is still processing, we can't suspend, so reject
-	 * the request.
-	 */
-	list_for_each_entry(as, &apm_user_list, list) {
-		if (as != sender && as->reader && as->writer && as->suser &&
-		    as->suspend_state != SUSPEND_NONE) {
-			ret = -EBUSY;
-			goto out;
-		}
-	}
-
-	list_for_each_entry(as, &apm_user_list, list) {
-		if (as != sender && as->reader && as->writer && as->suser) {
-			as->suspend_state = SUSPEND_PENDING;
-			suspends_pending++;
-			queue_add_event(&as->queue, event);
-			ret = 0;
-		}
-	}
- out:
-	up_read(&user_list_lock);
-	mutex_unlock(&state_lock);
-	wake_up_interruptible(&apm_waitqueue);
-	return ret;
-}
-
-static void apm_suspend(void)
-{
-	struct apm_user *as;
-	int err = pm_suspend(PM_SUSPEND_MEM);
-
-	/*
-	 * Anyone on the APM queues will think we're still suspended.
-	 * Send a message so everyone knows we're now awake again.
-	 */
-	queue_event(APM_NORMAL_RESUME);
-
-	/*
-	 * Finally, wake up anyone who is sleeping on the suspend.
-	 */
-	mutex_lock(&state_lock);
-	down_read(&user_list_lock);
-	list_for_each_entry(as, &apm_user_list, list) {
-		if (as->suspend_state == SUSPEND_WAIT ||
-		    as->suspend_state == SUSPEND_ACKED) {
-			as->suspend_result = err;
-			as->suspend_state = SUSPEND_DONE;
-		}
-	}
-	up_read(&user_list_lock);
-	mutex_unlock(&state_lock);
-
-	wake_up(&apm_suspend_waitqueue);
-}
-
 static ssize_t apm_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos)
 {
 	struct apm_user *as = fp->private_data;
@@ -308,25 +280,22 @@ apm_ioctl(struct inode * inode, struct file *filp, u_int cmd, u_long arg)
 
 		as->suspend_result = -EINTR;
 
-		if (as->suspend_state == SUSPEND_READ) {
-			int pending;
-
+		switch (as->suspend_state) {
+		case SUSPEND_READ:
 			/*
 			 * If we read a suspend command from /dev/apm_bios,
 			 * then the corresponding APM_IOC_SUSPEND ioctl is
 			 * interpreted as an acknowledge.
 			 */
 			as->suspend_state = SUSPEND_ACKED;
-			suspends_pending--;
-			pending = suspends_pending == 0;
+			atomic_dec(&suspend_acks_pending);
 			mutex_unlock(&state_lock);
 
 			/*
-			 * If there are no further acknowledges required,
-			 * suspend the system.
+			 * suspend_acks_pending changed, the notifier needs to
+			 * be woken up for this
 			 */
-			if (pending)
-				apm_suspend();
+			wake_up(&apm_suspend_waitqueue);
 
 			/*
 			 * Wait for the suspend/resume to complete.  If there
@@ -342,35 +311,21 @@ apm_ioctl(struct inode * inode, struct file *filp, u_int cmd, u_long arg)
 			 * try_to_freeze() in freezer_count() will not trigger
 			 */
 			freezer_count();
-		} else {
+			break;
+		case SUSPEND_ACKTO:
+			as->suspend_result = -ETIMEDOUT;
+			mutex_unlock(&state_lock);
+			break;
+		default:
 			as->suspend_state = SUSPEND_WAIT;
 			mutex_unlock(&state_lock);
 
 			/*
 			 * Otherwise it is a request to suspend the system.
-			 * Queue an event for all readers, and expect an
-			 * acknowledge from all writers who haven't already
-			 * acknowledged.
-			 */
-			err = queue_suspend_event(APM_USER_SUSPEND, as);
-			if (err < 0) {
-				/*
-				 * Avoid taking the lock here - this
-				 * should be fine.
-				 */
-				as->suspend_state = SUSPEND_NONE;
-				break;
-			}
-
-			if (err > 0)
-				apm_suspend();
-
-			/*
-			 * Wait for the suspend/resume to complete.  If there
-			 * are pending acknowledges, we wait here for them.
+			 * Just invoke pm_suspend(), we'll handle it from
+			 * there via the notifier.
 			 */
-			wait_event_freezable(apm_suspend_waitqueue,
-					 as->suspend_state == SUSPEND_DONE);
+			as->suspend_result = pm_suspend(PM_SUSPEND_MEM);
 		}
 
 		mutex_lock(&state_lock);
@@ -386,7 +341,6 @@ apm_ioctl(struct inode * inode, struct file *filp, u_int cmd, u_long arg)
 static int apm_release(struct inode * inode, struct file * filp)
 {
 	struct apm_user *as = filp->private_data;
-	int pending = 0;
 
 	filp->private_data = NULL;
 
@@ -396,18 +350,15 @@ static int apm_release(struct inode * inode, struct file * filp)
 
 	/*
 	 * We are now unhooked from the chain.  As far as new
-	 * events are concerned, we no longer exist.  However, we
-	 * need to balance suspends_pending, which means the
-	 * possibility of sleeping.
+	 * events are concerned, we no longer exist.
 	 */
 	mutex_lock(&state_lock);
-	if (as->suspend_state != SUSPEND_NONE) {
-		suspends_pending -= 1;
-		pending = suspends_pending == 0;
-	}
+	if (as->suspend_state == SUSPEND_PENDING ||
+	    as->suspend_state == SUSPEND_READ)
+		atomic_dec(&suspend_acks_pending);
 	mutex_unlock(&state_lock);
-	if (pending)
-		apm_suspend();
+
+	wake_up(&apm_suspend_waitqueue);
 
 	kfree(as);
 	return 0;
@@ -545,7 +496,6 @@ static int kapmd(void *arg)
 {
 	do {
 		apm_event_t event;
-		int ret;
 
 		wait_event_interruptible(kapmd_wait,
 				!queue_empty(&kapmd_queue) || kthread_should_stop());
@@ -570,20 +520,13 @@ static int kapmd(void *arg)
 
 		case APM_USER_SUSPEND:
 		case APM_SYS_SUSPEND:
-			ret = queue_suspend_event(event, NULL);
-			if (ret < 0) {
-				/*
-				 * We were busy.  Try again in 50ms.
-				 */
-				queue_add_event(&kapmd_queue, event);
-				msleep(50);
-			}
-			if (ret > 0)
-				apm_suspend();
+			pm_suspend(PM_SUSPEND_MEM);
 			break;
 
 		case APM_CRITICAL_SUSPEND:
-			apm_suspend();
+			atomic_inc(&userspace_notification_inhibit);
+			pm_suspend(PM_SUSPEND_MEM);
+			atomic_dec(&userspace_notification_inhibit);
 			break;
 		}
 	} while (1);
@@ -591,6 +534,120 @@ static int kapmd(void *arg)
 	return 0;
 }
 
+static int apm_suspend_notifier(struct notifier_block *nb,
+				unsigned long event,
+				void *dummy)
+{
+	struct apm_user *as;
+	int err;
+
+	/* short-cut emergency suspends */
+	if (atomic_read(&userspace_notification_inhibit))
+		return NOTIFY_DONE;
+
+	switch (event) {
+	case PM_SUSPEND_PREPARE:
+		/*
+		 * Queue an event to all "writer" users that we want
+		 * to suspend and need their ack.
+		 */
+		mutex_lock(&state_lock);
+		down_read(&user_list_lock);
+
+		list_for_each_entry(as, &apm_user_list, list) {
+			if (as->suspend_state != SUSPEND_WAIT && as->reader &&
+			    as->writer && as->suser) {
+				as->suspend_state = SUSPEND_PENDING;
+				atomic_inc(&suspend_acks_pending);
+				queue_add_event(&as->queue, APM_USER_SUSPEND);
+			}
+		}
+
+		up_read(&user_list_lock);
+		mutex_unlock(&state_lock);
+		wake_up_interruptible(&apm_waitqueue);
+
+		/*
+		 * Wait for the the suspend_acks_pending variable to drop to
+		 * zero, meaning everybody acked the suspend event (or the
+		 * process was killed.)
+		 *
+		 * If the app won't answer within a short while we assume it
+		 * locked up and ignore it.
+		 */
+		err = wait_event_interruptible_timeout(
+			apm_suspend_waitqueue,
+			atomic_read(&suspend_acks_pending) == 0,
+			5*HZ);
+
+		/* timed out */
+		if (err == 0) {
+			/*
+			 * Move anybody who timed out to "ack timeout" state.
+			 *
+			 * We could time out and the userspace does the ACK
+			 * right after we time out but before we enter the
+			 * locked section here, but that's fine.
+			 */
+			mutex_lock(&state_lock);
+			down_read(&user_list_lock);
+			list_for_each_entry(as, &apm_user_list, list) {
+				if (as->suspend_state == SUSPEND_PENDING ||
+				    as->suspend_state == SUSPEND_READ) {
+					as->suspend_state = SUSPEND_ACKTO;
+					atomic_dec(&suspend_acks_pending);
+				}
+			}
+			up_read(&user_list_lock);
+			mutex_unlock(&state_lock);
+		}
+
+		/* let suspend proceed */
+		if (err >= 0)
+			return NOTIFY_OK;
+
+		/* interrupted by signal */
+		return NOTIFY_BAD;
+
+	case PM_POST_SUSPEND:
+		/*
+		 * Anyone on the APM queues will think we're still suspended.
+		 * Send a message so everyone knows we're now awake again.
+		 */
+		queue_event(APM_NORMAL_RESUME);
+
+		/*
+		 * Finally, wake up anyone who is sleeping on the suspend.
+		 */
+		mutex_lock(&state_lock);
+		down_read(&user_list_lock);
+		list_for_each_entry(as, &apm_user_list, list) {
+			if (as->suspend_state == SUSPEND_ACKED) {
+				/*
+				 * TODO: maybe grab error code, needs core
+				 * changes to push the error to the notifier
+				 * chain (could use the second parameter if
+				 * implemented)
+				 */
+				as->suspend_result = 0;
+				as->suspend_state = SUSPEND_DONE;
+			}
+		}
+		up_read(&user_list_lock);
+		mutex_unlock(&state_lock);
+
+		wake_up(&apm_suspend_waitqueue);
+		return NOTIFY_OK;
+
+	default:
+		return NOTIFY_DONE;
+	}
+}
+
+static struct notifier_block apm_notif_block = {
+	.notifier_call = apm_suspend_notifier,
+};
+
 static int __init apm_init(void)
 {
 	int ret;
@@ -604,7 +661,7 @@ static int __init apm_init(void)
 	if (IS_ERR(kapmd_tsk)) {
 		ret = PTR_ERR(kapmd_tsk);
 		kapmd_tsk = NULL;
-		return ret;
+		goto out;
 	}
 	wake_up_process(kapmd_tsk);
 
@@ -613,16 +670,27 @@ static int __init apm_init(void)
 #endif
 
 	ret = misc_register(&apm_device);
-	if (ret != 0) {
-		remove_proc_entry("apm", NULL);
-		kthread_stop(kapmd_tsk);
-	}
+	if (ret)
+		goto out_stop;
 
+	ret = register_pm_notifier(&apm_notif_block);
+	if (ret)
+		goto out_unregister;
+
+	return 0;
+
+ out_unregister:
+	misc_deregister(&apm_device);
+ out_stop:
+	remove_proc_entry("apm", NULL);
+	kthread_stop(kapmd_tsk);
+ out:
 	return ret;
 }
 
 static void __exit apm_exit(void)
 {
+	unregister_pm_notifier(&apm_notif_block);
 	misc_deregister(&apm_device);
 	remove_proc_entry("apm", NULL);
 
diff --git a/drivers/char/bsr.c b/drivers/char/bsr.c
new file mode 100644
index 00000000000..b650b4e48e5
--- /dev/null
+++ b/drivers/char/bsr.c
@@ -0,0 +1,312 @@
+/* IBM POWER Barrier Synchronization Register Driver
+ *
+ * Copyright IBM Corporation 2008
+ *
+ * Author: Sonny Rao <sonnyrao@us.ibm.com>
+ *
+ * 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
+ */
+
+#include <linux/kernel.h>
+#include <linux/of.h>
+#include <linux/of_device.h>
+#include <linux/of_platform.h>
+#include <linux/module.h>
+#include <linux/cdev.h>
+#include <linux/list.h>
+#include <linux/mm.h>
+#include <asm/io.h>
+
+/*
+ This driver exposes a special register which can be used for fast
+ synchronization across a large SMP machine.  The hardware is exposed
+ as an array of bytes where each process will write to one of the bytes to
+ indicate it has finished the current stage and this update is broadcast to
+ all processors without having to bounce a cacheline between them. In
+ POWER5 and POWER6 there is one of these registers per SMP,  but it is
+ presented in two forms; first, it is given as a whole and then as a number
+ of smaller registers which alias to parts of the single whole register.
+ This can potentially allow multiple groups of processes to each have their
+ own private synchronization device.
+
+ Note that this hardware *must* be written to using *only* single byte writes.
+ It may be read using 1, 2, 4, or 8 byte loads which must be aligned since
+ this region is treated as cache-inhibited  processes should also use a
+ full sync before and after writing to the BSR to ensure all stores and
+ the BSR update have made it to all chips in the system
+*/
+
+/* This is arbitrary number, up to Power6 it's been 17 or fewer  */
+#define BSR_MAX_DEVS (32)
+
+struct bsr_dev {
+	u64      bsr_addr;     /* Real address */
+	u64      bsr_len;      /* length of mem region we can map */
+	unsigned bsr_bytes;    /* size of the BSR reg itself */
+	unsigned bsr_stride;   /* interval at which BSR repeats in the page */
+	unsigned bsr_type;     /* maps to enum below */
+	unsigned bsr_num;      /* bsr id number for its type */
+	int      bsr_minor;
+
+	dev_t    bsr_dev;
+	struct cdev bsr_cdev;
+	struct device *bsr_device;
+	char     bsr_name[32];
+
+};
+
+static unsigned num_bsr_devs;
+static struct bsr_dev *bsr_devs;
+static struct class *bsr_class;
+static int bsr_major;
+
+enum {
+	BSR_8   = 0,
+	BSR_16  = 1,
+	BSR_64  = 2,
+	BSR_128 = 3,
+	BSR_UNKNOWN = 4,
+	BSR_MAX = 5,
+};
+
+static unsigned bsr_types[BSR_MAX];
+
+static ssize_t
+bsr_size_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bsr_dev *bsr_dev = dev_get_drvdata(dev);
+	return sprintf(buf, "%u\n", bsr_dev->bsr_bytes);
+}
+
+static ssize_t
+bsr_stride_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bsr_dev *bsr_dev = dev_get_drvdata(dev);
+	return sprintf(buf, "%u\n", bsr_dev->bsr_stride);
+}
+
+static ssize_t
+bsr_len_show(struct device *dev, struct device_attribute *attr, char *buf)
+{
+	struct bsr_dev *bsr_dev = dev_get_drvdata(dev);
+	return sprintf(buf, "%lu\n", bsr_dev->bsr_len);
+}
+
+static struct device_attribute bsr_dev_attrs[] = {
+	__ATTR(bsr_size, S_IRUGO, bsr_size_show, NULL),
+	__ATTR(bsr_stride, S_IRUGO, bsr_stride_show, NULL),
+	__ATTR(bsr_length, S_IRUGO, bsr_len_show, NULL),
+	__ATTR_NULL
+};
+
+static int bsr_mmap(struct file *filp, struct vm_area_struct *vma)
+{
+	unsigned long size   = vma->vm_end - vma->vm_start;
+	struct bsr_dev *dev = filp->private_data;
+
+	if (size > dev->bsr_len || (size & (PAGE_SIZE-1)))
+		return -EINVAL;
+
+	vma->vm_flags |= (VM_IO | VM_DONTEXPAND);
+	vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
+
+	if (io_remap_pfn_range(vma, vma->vm_start, dev->bsr_addr >> PAGE_SHIFT,
+			       size, vma->vm_page_prot))
+		return -EAGAIN;
+
+	return 0;
+}
+
+static int bsr_open(struct inode * inode, struct file * filp)
+{
+	struct cdev *cdev = inode->i_cdev;
+	struct bsr_dev *dev = container_of(cdev, struct bsr_dev, bsr_cdev);
+
+	filp->private_data = dev;
+	return 0;
+}
+
+const static struct file_operations bsr_fops = {
+	.owner = THIS_MODULE,
+	.mmap  = bsr_mmap,
+	.open  = bsr_open,
+};
+
+static void bsr_cleanup_devs(void)
+{
+	int i;
+	for (i=0 ; i < num_bsr_devs; i++) {
+		struct bsr_dev *cur = bsr_devs + i;
+		if (cur->bsr_device) {
+			cdev_del(&cur->bsr_cdev);
+			device_del(cur->bsr_device);
+		}
+	}
+
+	kfree(bsr_devs);
+}
+
+static int bsr_create_devs(struct device_node *bn)
+{
+	int bsr_stride_len, bsr_bytes_len;
+	const u32 *bsr_stride;
+	const u32 *bsr_bytes;
+	unsigned i;
+
+	bsr_stride = of_get_property(bn, "ibm,lock-stride", &bsr_stride_len);
+	bsr_bytes  = of_get_property(bn, "ibm,#lock-bytes", &bsr_bytes_len);
+
+	if (!bsr_stride || !bsr_bytes ||
+	    (bsr_stride_len != bsr_bytes_len)) {
+		printk(KERN_ERR "bsr of-node has missing/incorrect property\n");
+		return -ENODEV;
+	}
+
+	num_bsr_devs = bsr_bytes_len / sizeof(u32);
+
+	/* only a warning, its informational since we'll fail and exit */
+	WARN_ON(num_bsr_devs > BSR_MAX_DEVS);
+
+	bsr_devs = kzalloc(sizeof(struct bsr_dev) * num_bsr_devs, GFP_KERNEL);
+	if (!bsr_devs)
+		return -ENOMEM;
+
+	for (i = 0 ; i < num_bsr_devs; i++) {
+		struct bsr_dev *cur = bsr_devs + i;
+		struct resource res;
+		int result;
+
+		result = of_address_to_resource(bn, i, &res);
+		if (result < 0) {
+			printk(KERN_ERR "bsr of-node has invalid reg property\n");
+			goto out_err;
+		}
+
+		cur->bsr_minor  = i;
+		cur->bsr_addr   = res.start;
+		cur->bsr_len    = res.end - res.start + 1;
+		cur->bsr_bytes  = bsr_bytes[i];
+		cur->bsr_stride = bsr_stride[i];
+		cur->bsr_dev    = MKDEV(bsr_major, i);
+
+		switch(cur->bsr_bytes) {
+		case 8:
+			cur->bsr_type = BSR_8;
+			break;
+		case 16:
+			cur->bsr_type = BSR_16;
+			break;
+		case 64:
+			cur->bsr_type = BSR_64;
+			break;
+		case 128:
+			cur->bsr_type = BSR_128;
+			break;
+		default:
+			cur->bsr_type = BSR_UNKNOWN;
+			printk(KERN_INFO "unknown BSR size %d\n",cur->bsr_bytes);
+		}
+
+		cur->bsr_num = bsr_types[cur->bsr_type];
+		bsr_types[cur->bsr_type] = cur->bsr_num + 1;
+		snprintf(cur->bsr_name, 32, "bsr%d_%d",
+			 cur->bsr_bytes, cur->bsr_num);
+
+		cdev_init(&cur->bsr_cdev, &bsr_fops);
+		result = cdev_add(&cur->bsr_cdev, cur->bsr_dev, 1);
+		if (result)
+			goto out_err;
+
+		cur->bsr_device = device_create_drvdata(bsr_class, NULL,
+							cur->bsr_dev,
+							cur, cur->bsr_name);
+		if (!cur->bsr_device) {
+			printk(KERN_ERR "device_create failed for %s\n",
+			       cur->bsr_name);
+			cdev_del(&cur->bsr_cdev);
+			goto out_err;
+		}
+	}
+
+	return 0;
+
+ out_err:
+
+	bsr_cleanup_devs();
+	return -ENODEV;
+}
+
+static int __init bsr_init(void)
+{
+	struct device_node *np;
+	dev_t bsr_dev = MKDEV(bsr_major, 0);
+	int ret = -ENODEV;
+	int result;
+
+	np = of_find_compatible_node(NULL, "ibm,bsr", "ibm,bsr");
+	if (!np)
+		goto out_err;
+
+	bsr_class = class_create(THIS_MODULE, "bsr");
+	if (IS_ERR(bsr_class)) {
+		printk(KERN_ERR "class_create() failed for bsr_class\n");
+		goto out_err_1;
+	}
+	bsr_class->dev_attrs = bsr_dev_attrs;
+
+	result = alloc_chrdev_region(&bsr_dev, 0, BSR_MAX_DEVS, "bsr");
+	bsr_major = MAJOR(bsr_dev);
+	if (result < 0) {
+		printk(KERN_ERR "alloc_chrdev_region() failed for bsr\n");
+		goto out_err_2;
+	}
+
+	if ((ret = bsr_create_devs(np)) < 0)
+		goto out_err_3;
+
+	of_node_put(np);
+
+	return 0;
+
+ out_err_3:
+	unregister_chrdev_region(bsr_dev, BSR_MAX_DEVS);
+
+ out_err_2:
+	class_destroy(bsr_class);
+
+ out_err_1:
+	of_node_put(np);
+
+ out_err:
+
+	return ret;
+}
+
+static void __exit  bsr_exit(void)
+{
+
+	bsr_cleanup_devs();
+
+	if (bsr_class)
+		class_destroy(bsr_class);
+
+	if (bsr_major)
+		unregister_chrdev_region(MKDEV(bsr_major, 0), BSR_MAX_DEVS);
+}
+
+module_init(bsr_init);
+module_exit(bsr_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Sonny Rao <sonnyrao@us.ibm.com>");
diff --git a/drivers/char/hvc_console.c b/drivers/char/hvc_console.c
index 44160d5ebca..2f9759d625c 100644
--- a/drivers/char/hvc_console.c
+++ b/drivers/char/hvc_console.c
@@ -675,12 +675,6 @@ static int hvc_poll(struct hvc_struct *hp)
 	return poll_mask;
 }
 
-#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
-extern cpumask_t cpus_in_xmon;
-#else
-static const cpumask_t cpus_in_xmon = CPU_MASK_NONE;
-#endif
-
 /*
  * This kthread is either polling or interrupt driven.  This is determined by
  * calling hvc_poll() who determines whether a console adapter support
@@ -698,7 +692,7 @@ static int khvcd(void *unused)
 		hvc_kicked = 0;
 		try_to_freeze();
 		wmb();
-		if (cpus_empty(cpus_in_xmon)) {
+		if (!cpus_are_in_xmon()) {
 			spin_lock(&hvc_structs_lock);
 			list_for_each_entry(hp, &hvc_structs, next) {
 				poll_mask |= hvc_poll(hp);
diff --git a/drivers/char/hvc_console.h b/drivers/char/hvc_console.h
index 8c59818050e..42ffb17e15d 100644
--- a/drivers/char/hvc_console.h
+++ b/drivers/char/hvc_console.h
@@ -60,4 +60,14 @@ extern struct hvc_struct * __devinit hvc_alloc(uint32_t vtermno, int irq,
 /* remove a vterm from hvc tty operation (modele_exit or hotplug remove) */
 extern int __devexit hvc_remove(struct hvc_struct *hp);
 
+
+#if defined(CONFIG_XMON) && defined(CONFIG_SMP)
+#include <asm/xmon.h>
+#else
+static inline int cpus_are_in_xmon(void)
+{
+	return 0;
+}
+#endif
+
 #endif // HVC_CONSOLE_H
diff --git a/drivers/char/hw_random/pasemi-rng.c b/drivers/char/hw_random/pasemi-rng.c
index 6d50e9bc700..7fa61dd1d9d 100644
--- a/drivers/char/hw_random/pasemi-rng.c
+++ b/drivers/char/hw_random/pasemi-rng.c
@@ -24,7 +24,7 @@
 #include <linux/platform_device.h>
 #include <linux/hw_random.h>
 #include <linux/delay.h>
-#include <asm/of_platform.h>
+#include <linux/of_platform.h>
 #include <asm/io.h>
 
 #define SDCRNG_CTL_REG			0x00
diff --git a/drivers/char/pcmcia/cm4000_cs.c b/drivers/char/pcmcia/cm4000_cs.c
index 59ca35156d8..e4a4fbd37d7 100644
--- a/drivers/char/pcmcia/cm4000_cs.c
+++ b/drivers/char/pcmcia/cm4000_cs.c
@@ -1439,7 +1439,7 @@ static long cmm_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 		DEBUGP(4, dev, "CMM_ABSENT flag set\n");
 		goto out;
 	}
-	rc = EINVAL;
+	rc = -EINVAL;
 
 	if (_IOC_TYPE(cmd) != CM_IOC_MAGIC) {
 		DEBUGP(4, dev, "ioctype mismatch\n");
diff --git a/drivers/char/viotape.c b/drivers/char/viotape.c
index 977f7d35e76..e5da98d8f9c 100644
--- a/drivers/char/viotape.c
+++ b/drivers/char/viotape.c
@@ -678,6 +678,17 @@ free_op:
 	return ret;
 }
 
+static long viotap_unlocked_ioctl(struct file *file,
+		unsigned int cmd, unsigned long arg)
+{
+	long rc;
+
+	lock_kernel();
+	rc = viotap_ioctl(file->f_path.dentry->d_inode, file, cmd, arg);
+	unlock_kernel();
+	return rc;
+}
+
 static int viotap_open(struct inode *inode, struct file *file)
 {
 	HvLpEvent_Rc hvrc;
@@ -786,12 +797,12 @@ free_op:
 }
 
 const struct file_operations viotap_fops = {
-	.owner =	THIS_MODULE,
-	.read =		viotap_read,
-	.write =	viotap_write,
-	.ioctl =	viotap_ioctl,
-	.open =		viotap_open,
-	.release =	viotap_release,
+	.owner =		THIS_MODULE,
+	.read =			viotap_read,
+	.write =		viotap_write,
+	.unlocked_ioctl =	viotap_unlocked_ioctl,
+	.open =			viotap_open,
+	.release =		viotap_release,
 };
 
 /* Handle interrupt events for tape */