linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
* [PATCH] block: replace BKL with global mutex
@ 2010-06-01 21:33 Arnd Bergmann
  2010-06-01 21:37 ` Christoph Hellwig
  0 siblings, 1 reply; 5+ messages in thread
From: Arnd Bergmann @ 2010-06-01 21:33 UTC (permalink / raw)
  To: Jens Axboe
  Cc: Arnd Bergmann, Jens Axboe, Vivek Goyal, Tejun Heo,
	Frederic Weisbecker, FUJITA Tomonori, Martin K. Petersen,
	Steven Rostedt, Douglas Gilbert, Ingo Molnar, John Kacur,
	linux-scsi, linux-kernel

The block layer is one of the remaining users
of the Big Kernel Lock. In there, it is used
mainly for serializing the blkdev_get and
blkdev_put functions and some ioctl implementations
as well as some less common open functions of
related character devices following a previous
pushdown and parts of the blktrace code.

The only one that seems to be a bit nasty is the
blkdev_get function which is actually recursive
and may try to get the BKL twice.

All users except the one in blkdev_get seem to
be outermost locks, meaning we don't rely on
the release-on-sleep semantics to avoid deadlocks.

The ctl_mutex (pktcdvd.ko), raw_mutex (raw.ko),
state_mutex (dasd.ko), reconfig_mutex (md.ko),
and jfs_log_mutex (jfs.ko) may be held when
blkdev_get is called, but as far as I can tell,
these mutexes are never acquired from any of the
functions that get converted in this patch.

In order to get rid of the BKL, this introduces
a new global mutex called blkdev_mutex, which
replaces the BKL in all drivers that directly
interact with the block layer. In case of blkdev_get,
the mutex is moved outside of the function itself
in order to avoid the recursive taking of blkdev_mutex.

Testing so far has shown no problems whatsoever
from this patch, but the usage in blkdev_get
may introduce extra latencies, and I may have
missed corner cases where an block device ioctl
function sleeps for a significant amount of time,
which may be harmful to the performance of other
threads.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Cc: Jens Axboe <jaxboe@fusionio.com>
Cc: Vivek Goyal <vgoyal@redhat.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: FUJITA Tomonori <fujita.tomonori@lab.ntt.co.jp>
Cc: "Martin K. Petersen" <martin.petersen@oracle.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Douglas Gilbert <dgilbert@interlog.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: linux-scsi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
---

Jens, would you consider this patch for 2.6.36 and take it into
your -next tree?

 block/bsg.c             |    2 --
 block/compat_ioctl.c    |    8 ++++----
 block/ioctl.c           |   24 ++++++++++++------------
 drivers/block/DAC960.c  |    4 ++--
 drivers/block/cciss.c   |    4 ++--
 drivers/scsi/sg.c       |    4 ++--
 fs/block_dev.c          |   20 +++++++++++++-------
 include/linux/blkdev.h  |    6 ++++++
 kernel/trace/blktrace.c |   14 ++++++++------
 9 files changed, 49 insertions(+), 37 deletions(-)

diff --git a/block/bsg.c b/block/bsg.c
index 82d5882..7c50a26 100644
--- a/block/bsg.c
+++ b/block/bsg.c
@@ -843,9 +843,7 @@ static int bsg_open(struct inode *inode, struct file *file)
 {
 	struct bsg_device *bd;
 
-	lock_kernel();
 	bd = bsg_get_device(inode, file);
-	unlock_kernel();
 
 	if (IS_ERR(bd))
 		return PTR_ERR(bd);
diff --git a/block/compat_ioctl.c b/block/compat_ioctl.c
index f26051f..11cfd3c 100644
--- a/block/compat_ioctl.c
+++ b/block/compat_ioctl.c
@@ -802,16 +802,16 @@ long compat_blkdev_ioctl(struct file *file, unsigned cmd, unsigned long arg)
 		return compat_put_u64(arg, bdev->bd_inode->i_size);
 
 	case BLKTRACESETUP32:
-		lock_kernel();
+		mutex_lock(&blkdev_mutex);
 		ret = compat_blk_trace_setup(bdev, compat_ptr(arg));
-		unlock_kernel();
+		mutex_unlock(&blkdev_mutex);
 		return ret;
 	case BLKTRACESTART: /* compatible */
 	case BLKTRACESTOP:  /* compatible */
 	case BLKTRACETEARDOWN: /* compatible */
-		lock_kernel();
+		mutex_lock(&blkdev_mutex);
 		ret = blk_trace_ioctl(bdev, cmd, compat_ptr(arg));
-		unlock_kernel();
+		mutex_unlock(&blkdev_mutex);
 		return ret;
 	default:
 		if (disk->fops->compat_ioctl)
diff --git a/block/ioctl.c b/block/ioctl.c
index e8eb679..6b8fde1 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -169,9 +169,9 @@ int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
 		return disk->fops->ioctl(bdev, mode, cmd, arg);
 
 	if (disk->fops->locked_ioctl) {
-		lock_kernel();
+		mutex_lock(&blkdev_mutex);
 		ret = disk->fops->locked_ioctl(bdev, mode, cmd, arg);
-		unlock_kernel();
+		mutex_unlock(&blkdev_mutex);
 		return ret;
 	}
 
@@ -206,10 +206,10 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 		if (ret != -EINVAL && ret != -ENOTTY)
 			return ret;
 
-		lock_kernel();
+		mutex_lock(&blkdev_mutex);
 		fsync_bdev(bdev);
 		invalidate_bdev(bdev);
-		unlock_kernel();
+		mutex_unlock(&blkdev_mutex);
 		return 0;
 
 	case BLKROSET:
@@ -221,9 +221,9 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 			return -EACCES;
 		if (get_user(n, (int __user *)(arg)))
 			return -EFAULT;
-		lock_kernel();
+		mutex_lock(&blkdev_mutex);
 		set_device_ro(bdev, n);
-		unlock_kernel();
+		mutex_unlock(&blkdev_mutex);
 		return 0;
 
 	case BLKDISCARD: {
@@ -309,14 +309,14 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 			bd_release(bdev);
 		return ret;
 	case BLKPG:
-		lock_kernel();
+		mutex_lock(&blkdev_mutex);
 		ret = blkpg_ioctl(bdev, (struct blkpg_ioctl_arg __user *) arg);
-		unlock_kernel();
+		mutex_unlock(&blkdev_mutex);
 		break;
 	case BLKRRPART:
-		lock_kernel();
+		mutex_lock(&blkdev_mutex);
 		ret = blkdev_reread_part(bdev);
-		unlock_kernel();
+		mutex_unlock(&blkdev_mutex);
 		break;
 	case BLKGETSIZE:
 		size = bdev->bd_inode->i_size;
@@ -329,9 +329,9 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 	case BLKTRACESTOP:
 	case BLKTRACESETUP:
 	case BLKTRACETEARDOWN:
-		lock_kernel();
+		mutex_lock(&blkdev_mutex);
 		ret = blk_trace_ioctl(bdev, cmd, (char __user *) arg);
-		unlock_kernel();
+		mutex_unlock(&blkdev_mutex);
 		break;
 	default:
 		ret = __blkdev_driver_ioctl(bdev, mode, cmd, arg);
diff --git a/drivers/block/DAC960.c b/drivers/block/DAC960.c
index c5f22bb..8faaa12 100644
--- a/drivers/block/DAC960.c
+++ b/drivers/block/DAC960.c
@@ -6620,7 +6620,7 @@ static long DAC960_gam_ioctl(struct file *file, unsigned int Request,
   long ErrorCode = 0;
   if (!capable(CAP_SYS_ADMIN)) return -EACCES;
 
-  lock_kernel();
+  mutex_lock(&blkdev_mutex);
   switch (Request)
     {
     case DAC960_IOCTL_GET_CONTROLLER_COUNT:
@@ -7051,7 +7051,7 @@ static long DAC960_gam_ioctl(struct file *file, unsigned int Request,
       default:
 	ErrorCode = -ENOTTY;
     }
-  unlock_kernel();
+  mutex_unlock(&blkdev_mutex);
   return ErrorCode;
 }
 
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 51ceaee..6bb6c4d 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -1027,9 +1027,9 @@ static int do_ioctl(struct block_device *bdev, fmode_t mode,
 		    unsigned cmd, unsigned long arg)
 {
 	int ret;
-	lock_kernel();
+	mutex_lock(&blkdev_mutex);
 	ret = cciss_ioctl(bdev, mode, cmd, arg);
-	unlock_kernel();
+	mutex_unlock(&blkdev_mutex);
 	return ret;
 }
 
diff --git a/drivers/scsi/sg.c b/drivers/scsi/sg.c
index ef752b2..927aea6 100644
--- a/drivers/scsi/sg.c
+++ b/drivers/scsi/sg.c
@@ -229,7 +229,7 @@ sg_open(struct inode *inode, struct file *filp)
 	int res;
 	int retval;
 
-	lock_kernel();
+	mutex_lock(&blkdev_mutex);
 	nonseekable_open(inode, filp);
 	SCSI_LOG_TIMEOUT(3, printk("sg_open: dev=%d, flags=0x%x\n", dev, flags));
 	sdp = sg_get_dev(dev);
@@ -307,7 +307,7 @@ error_out:
 sg_put:
 	if (sdp)
 		sg_put_dev(sdp);
-	unlock_kernel();
+	mutex_unlock(&blkdev_mutex);
 	return retval;
 }
 
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 7346c96..06882f9 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -29,6 +29,9 @@
 #include <asm/uaccess.h>
 #include "internal.h"
 
+DEFINE_MUTEX(blkdev_mutex);
+EXPORT_SYMBOL_GPL(blkdev_mutex);
+
 struct bdev_inode {
 	struct block_device bdev;
 	struct inode vfs_inode;
@@ -1321,7 +1324,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
 		return ret;
 	}
 
-	lock_kernel();
  restart:
 
 	ret = -ENXIO;
@@ -1407,7 +1409,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
 	if (for_part)
 		bdev->bd_part_count++;
 	mutex_unlock(&bdev->bd_mutex);
-	unlock_kernel();
 	return 0;
 
  out_clear:
@@ -1421,7 +1422,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
  out_unlock_bdev:
 	mutex_unlock(&bdev->bd_mutex);
  out_unlock_kernel:
-	unlock_kernel();
 
 	if (disk)
 		module_put(disk->fops->owner);
@@ -1433,7 +1433,11 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
 
 int blkdev_get(struct block_device *bdev, fmode_t mode)
 {
-	return __blkdev_get(bdev, mode, 0);
+	int ret;
+	mutex_lock(&blkdev_mutex);
+	ret = __blkdev_get(bdev, mode, 0);
+	mutex_unlock(&blkdev_mutex);
+	return ret;
 }
 EXPORT_SYMBOL(blkdev_get);
 
@@ -1491,7 +1495,6 @@ static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
 	struct block_device *victim = NULL;
 
 	mutex_lock_nested(&bdev->bd_mutex, for_part);
-	lock_kernel();
 	if (for_part)
 		bdev->bd_part_count--;
 
@@ -1516,7 +1519,6 @@ static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
 			victim = bdev->bd_contains;
 		bdev->bd_contains = NULL;
 	}
-	unlock_kernel();
 	mutex_unlock(&bdev->bd_mutex);
 	bdput(bdev);
 	if (victim)
@@ -1526,7 +1528,11 @@ static int __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part)
 
 int blkdev_put(struct block_device *bdev, fmode_t mode)
 {
-	return __blkdev_put(bdev, mode, 0);
+	int ret;
+	mutex_lock(&blkdev_mutex);
+	ret = __blkdev_put(bdev, mode, 0);
+	mutex_unlock(&blkdev_mutex);
+	return ret;
 }
 EXPORT_SYMBOL(blkdev_put);
 
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8b7f5e0..69aa7f1 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1340,6 +1340,12 @@ struct block_device_operations {
 
 extern int __blkdev_driver_ioctl(struct block_device *, fmode_t, unsigned int,
 				 unsigned long);
+
+/*
+ * replaces the big kernel lock in the block subsystem
+ */
+extern struct mutex blkdev_mutex;
+
 #else /* CONFIG_BLOCK */
 /*
  * stubs for when the block layer is configured out
diff --git a/kernel/trace/blktrace.c b/kernel/trace/blktrace.c
index 36ea2b6..fcf17e7 100644
--- a/kernel/trace/blktrace.c
+++ b/kernel/trace/blktrace.c
@@ -305,7 +305,7 @@ static int blk_dropped_open(struct inode *inode, struct file *filp)
 {
 	filp->private_data = inode->i_private;
 
-	return 0;
+	return nonseekable_open(inode, filp);
 }
 
 static ssize_t blk_dropped_read(struct file *filp, char __user *buffer,
@@ -323,13 +323,14 @@ static const struct file_operations blk_dropped_fops = {
 	.owner =	THIS_MODULE,
 	.open =		blk_dropped_open,
 	.read =		blk_dropped_read,
+	.llseek =	no_llseek,
 };
 
 static int blk_msg_open(struct inode *inode, struct file *filp)
 {
 	filp->private_data = inode->i_private;
 
-	return 0;
+	return nonseekable_open(inode, filp);
 }
 
 static ssize_t blk_msg_write(struct file *filp, const char __user *buffer,
@@ -362,6 +363,7 @@ static const struct file_operations blk_msg_fops = {
 	.owner =	THIS_MODULE,
 	.open =		blk_msg_open,
 	.write =	blk_msg_write,
+	.llseek =	no_llseek,
 };
 
 /*
@@ -1601,7 +1603,7 @@ static ssize_t sysfs_blk_trace_attr_show(struct device *dev,
 	struct block_device *bdev;
 	ssize_t ret = -ENXIO;
 
-	lock_kernel();
+	mutex_lock(&blkdev_mutex);
 	bdev = bdget(part_devt(p));
 	if (bdev == NULL)
 		goto out_unlock_kernel;
@@ -1633,7 +1635,7 @@ out_unlock_bdev:
 out_bdput:
 	bdput(bdev);
 out_unlock_kernel:
-	unlock_kernel();
+	mutex_unlock(&blkdev_mutex);
 	return ret;
 }
 
@@ -1663,7 +1665,7 @@ static ssize_t sysfs_blk_trace_attr_store(struct device *dev,
 
 	ret = -ENXIO;
 
-	lock_kernel();
+	mutex_lock(&blkdev_mutex);
 	p = dev_to_part(dev);
 	bdev = bdget(part_devt(p));
 	if (bdev == NULL)
@@ -1703,7 +1705,7 @@ out_unlock_bdev:
 out_bdput:
 	bdput(bdev);
 out_unlock_kernel:
-	unlock_kernel();
+	mutex_unlock(&blkdev_mutex);
 out:
 	return ret ? ret : count;
 }
-- 
1.7.0.4


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH] block: replace BKL with global mutex
  2010-06-01 21:33 [PATCH] block: replace BKL with global mutex Arnd Bergmann
@ 2010-06-01 21:37 ` Christoph Hellwig
  2010-06-01 22:43   ` [PATCH] block: push down BKL into .locked_ioctl Arnd Bergmann
  0 siblings, 1 reply; 5+ messages in thread
From: Christoph Hellwig @ 2010-06-01 21:37 UTC (permalink / raw)
  To: Arnd Bergmann
  Cc: Jens Axboe, Vivek Goyal, Tejun Heo, Frederic Weisbecker,
	FUJITA Tomonori, Martin K. Petersen, Steven Rostedt,
	Douglas Gilbert, Ingo Molnar, John Kacur, linux-scsi,
	linux-kernel

NAK.  You're really only creation a mini-BKL here without
sorting out the locking.  Please go through the individual
callers and sort them out.  Start by pushing the remaining
ioctls to the unlocked version and moving the BKL into the
->open and ->release methods.


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH] block: push down BKL into .locked_ioctl
  2010-06-01 21:37 ` Christoph Hellwig
@ 2010-06-01 22:43   ` Arnd Bergmann
  2010-06-02 10:16     ` Christoph Hellwig
  0 siblings, 1 reply; 5+ messages in thread
From: Arnd Bergmann @ 2010-06-01 22:43 UTC (permalink / raw)
  To: Christoph Hellwig
  Cc: Jens Axboe, Vivek Goyal, Tejun Heo, Frederic Weisbecker,
	FUJITA Tomonori, Martin K. Petersen, Steven Rostedt,
	Douglas Gilbert, Ingo Molnar, John Kacur, linux-scsi,
	linux-kernel

As a preparation for the removal of the big kernel
lock in the block layer, this removes the BKL
from the common ioctl handling code, moving it
into every single driver still using it.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
 block/ioctl.c                   |   11 +----------
 drivers/block/amiflop.c         |   15 ++++++++++++++-
 drivers/block/ataflop.c         |   14 +++++++++++++-
 drivers/block/brd.c             |    5 ++++-
 drivers/block/cciss.c           |    8 +++++---
 drivers/block/cpqarray.c        |   18 ++++++++++++++++--
 drivers/block/floppy.c          |   15 ++++++++++++++-
 drivers/block/nbd.c             |    5 ++++-
 drivers/block/paride/pcd.c      |   11 +++++++++--
 drivers/block/paride/pd.c       |    5 ++++-
 drivers/block/paride/pf.c       |    6 +++++-
 drivers/block/pktcdvd.c         |   11 ++++++++---
 drivers/block/swim.c            |    5 ++++-
 drivers/block/swim3.c           |   15 ++++++++++++++-
 drivers/block/ub.c              |   10 ++++++++--
 drivers/block/virtio_blk.c      |   15 ++++++++++++++-
 drivers/block/xd.c              |   15 ++++++++++++++-
 drivers/block/xd.h              |    2 +-
 drivers/block/xen-blkfront.c    |    2 +-
 drivers/cdrom/gdrom.c           |   11 +++++++++--
 drivers/cdrom/viocd.c           |   11 +++++++++--
 drivers/ide/ide-cd.c            |   16 +++++++++++++++-
 drivers/ide/ide-disk_ioctl.c    |    9 +++++++--
 drivers/ide/ide-floppy_ioctl.c  |   12 +++++++++---
 drivers/ide/ide-gd.c            |    2 +-
 drivers/ide/ide-tape.c          |   10 ++++++++--
 drivers/message/i2o/i2o_block.c |   15 ++++++++++++++-
 drivers/mtd/mtd_blkdevs.c       |    5 ++++-
 drivers/scsi/sd.c               |   15 ++++++++++++++-
 drivers/scsi/sr.c               |   15 ++++++++++++++-
 include/linux/blkdev.h          |    1 -
 31 files changed, 257 insertions(+), 53 deletions(-)


On Tuesday 01 June 2010 23:37:55 Christoph Hellwig wrote:
> NAK.  You're really only creation a mini-BKL here without
> sorting out the locking.  Please go through the individual
> callers and sort them out.  Start by pushing the remaining
> ioctls to the unlocked version and moving the BKL into the
> ->open and ->release methods.
 
Ok, here comes the first step. Can you be more specific
about what you mean with the open and release methods? 
Do you mean the sg.c and bsg.c chrdev file operations?

	Arnd

diff --git a/block/ioctl.c b/block/ioctl.c
index e8eb679..1cfa8d4 100644
--- a/block/ioctl.c
+++ b/block/ioctl.c
@@ -163,18 +163,10 @@ int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
 			unsigned cmd, unsigned long arg)
 {
 	struct gendisk *disk = bdev->bd_disk;
-	int ret;
 
 	if (disk->fops->ioctl)
 		return disk->fops->ioctl(bdev, mode, cmd, arg);
 
-	if (disk->fops->locked_ioctl) {
-		lock_kernel();
-		ret = disk->fops->locked_ioctl(bdev, mode, cmd, arg);
-		unlock_kernel();
-		return ret;
-	}
-
 	return -ENOTTY;
 }
 /*
@@ -185,8 +177,7 @@ int __blkdev_driver_ioctl(struct block_device *bdev, fmode_t mode,
 EXPORT_SYMBOL_GPL(__blkdev_driver_ioctl);
 
 /*
- * always keep this in sync with compat_blkdev_ioctl() and
- * compat_blkdev_locked_ioctl()
+ * always keep this in sync with compat_blkdev_ioctl()
  */
 int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 			unsigned long arg)
diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index 832798a..7a51535 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -60,6 +60,7 @@
 #include <linux/hdreg.h>
 #include <linux/delay.h>
 #include <linux/init.h>
+#include <linux/smp_lock.h>
 #include <linux/amifdreg.h>
 #include <linux/amifd.h>
 #include <linux/buffer_head.h>
@@ -1500,6 +1501,18 @@ static int fd_ioctl(struct block_device *bdev, fmode_t mode,
 	return 0;
 }
 
+static int fd_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long param)
+{
+	int ret;
+
+	lock_kernel();
+	ret = fd_ioctl(bdev, mode, cmd, param);
+	unlock_kernel();
+
+	return ret;
+}
+
 static void fd_probe(int dev)
 {
 	unsigned long code;
@@ -1638,7 +1651,7 @@ static const struct block_device_operations floppy_fops = {
 	.owner		= THIS_MODULE,
 	.open		= floppy_open,
 	.release	= floppy_release,
-	.locked_ioctl	= fd_ioctl,
+	.ioctl		= fd_unlocked_ioctl,
 	.getgeo		= fd_getgeo,
 	.media_changed	= amiga_floppy_change,
 };
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index e35cf59..09ae46f 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -67,6 +67,7 @@
 #include <linux/delay.h>
 #include <linux/init.h>
 #include <linux/blkdev.h>
+#include <linux/smp_lock.h>
 
 #include <asm/atafd.h>
 #include <asm/atafdreg.h>
@@ -1665,6 +1666,17 @@ static int fd_ioctl(struct block_device *bdev, fmode_t mode,
 	}
 }
 
+static int fd_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long arg)
+{
+	int ret;
+
+	lock_kernel();
+	ret = fd_ioctl(bdev, mode, cmd, arg);
+	unlock_kernel();
+
+	return ret;
+}
 
 /* Initialize the 'unit' variable for drive 'drive' */
 
@@ -1855,7 +1867,7 @@ static const struct block_device_operations floppy_fops = {
 	.owner		= THIS_MODULE,
 	.open		= floppy_open,
 	.release	= floppy_release,
-	.locked_ioctl	= fd_ioctl,
+	.ioctl		= fd_unlocked_ioctl,
 	.media_changed	= check_floppy_change,
 	.revalidate_disk= floppy_revalidate,
 };
diff --git a/drivers/block/brd.c b/drivers/block/brd.c
index 6081e81..b424cca 100644
--- a/drivers/block/brd.c
+++ b/drivers/block/brd.c
@@ -15,6 +15,7 @@
 #include <linux/blkdev.h>
 #include <linux/bio.h>
 #include <linux/highmem.h>
+#include <linux/smp_lock.h>
 #include <linux/radix-tree.h>
 #include <linux/buffer_head.h> /* invalidate_bh_lrus() */
 #include <linux/slab.h>
@@ -355,6 +356,7 @@ static int brd_ioctl(struct block_device *bdev, fmode_t mode,
 	 * ram device BLKFLSBUF has special semantics, we want to actually
 	 * release and destroy the ramdisk data.
 	 */
+	lock_kernel();
 	mutex_lock(&bdev->bd_mutex);
 	error = -EBUSY;
 	if (bdev->bd_openers <= 1) {
@@ -371,13 +373,14 @@ static int brd_ioctl(struct block_device *bdev, fmode_t mode,
 		error = 0;
 	}
 	mutex_unlock(&bdev->bd_mutex);
+	unlock_kernel();
 
 	return error;
 }
 
 static const struct block_device_operations brd_fops = {
 	.owner =		THIS_MODULE,
-	.locked_ioctl =		brd_ioctl,
+	.ioctl =		brd_ioctl,
 #ifdef CONFIG_BLK_DEV_XIP
 	.direct_access =	brd_direct_access,
 #endif
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 51ceaee..6c3c8c4 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -170,6 +170,8 @@ static void do_cciss_request(struct request_queue *q);
 static irqreturn_t do_cciss_intr(int irq, void *dev_id);
 static int cciss_open(struct block_device *bdev, fmode_t mode);
 static int cciss_release(struct gendisk *disk, fmode_t mode);
+static int do_ioctl(struct block_device *bdev, fmode_t mode,
+		    unsigned int cmd, unsigned long arg);
 static int cciss_ioctl(struct block_device *bdev, fmode_t mode,
 		       unsigned int cmd, unsigned long arg);
 static int cciss_getgeo(struct block_device *bdev, struct hd_geometry *geo);
@@ -223,7 +225,7 @@ static const struct block_device_operations cciss_fops = {
 	.owner = THIS_MODULE,
 	.open = cciss_open,
 	.release = cciss_release,
-	.locked_ioctl = cciss_ioctl,
+	.ioctl = do_ioctl,
 	.getgeo = cciss_getgeo,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl = cciss_compat_ioctl,
@@ -1021,8 +1023,6 @@ static int cciss_release(struct gendisk *disk, fmode_t mode)
 	return 0;
 }
 
-#ifdef CONFIG_COMPAT
-
 static int do_ioctl(struct block_device *bdev, fmode_t mode,
 		    unsigned cmd, unsigned long arg)
 {
@@ -1033,6 +1033,8 @@ static int do_ioctl(struct block_device *bdev, fmode_t mode,
 	return ret;
 }
 
+#ifdef CONFIG_COMPAT
+
 static int cciss_ioctl32_passthru(struct block_device *bdev, fmode_t mode,
 				  unsigned cmd, unsigned long arg);
 static int cciss_ioctl32_big_passthru(struct block_device *bdev, fmode_t mode,
diff --git a/drivers/block/cpqarray.c b/drivers/block/cpqarray.c
index 91d1163..072e57c 100644
--- a/drivers/block/cpqarray.c
+++ b/drivers/block/cpqarray.c
@@ -35,6 +35,7 @@
 #include <linux/seq_file.h>
 #include <linux/init.h>
 #include <linux/hdreg.h>
+#include <linux/smp_lock.h>
 #include <linux/spinlock.h>
 #include <linux/blkdev.h>
 #include <linux/genhd.h>
@@ -159,7 +160,7 @@ static int sendcmd(
 
 static int ida_open(struct block_device *bdev, fmode_t mode);
 static int ida_release(struct gendisk *disk, fmode_t mode);
-static int ida_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg);
+static int ida_unlocked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg);
 static int ida_getgeo(struct block_device *bdev, struct hd_geometry *geo);
 static int ida_ctlr_ioctl(ctlr_info_t *h, int dsk, ida_ioctl_t *io);
 
@@ -197,7 +198,7 @@ static const struct block_device_operations ida_fops  = {
 	.owner		= THIS_MODULE,
 	.open		= ida_open,
 	.release	= ida_release,
-	.locked_ioctl	= ida_ioctl,
+	.ioctl		= ida_unlocked_ioctl,
 	.getgeo		= ida_getgeo,
 	.revalidate_disk= ida_revalidate,
 };
@@ -1192,6 +1193,19 @@ out_passthru:
 	}
 		
 }
+
+static int ida_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long param)
+{
+	int ret;
+
+	lock_kernel();
+	ret = ida_ioctl(bdev, mode, cmd, param);
+	unlock_kernel();
+
+	return ret;
+}
+
 /*
  * ida_ctlr_ioctl is for passing commands to the controller from userspace.
  * The command block (io) has already been copied to kernel space for us,
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index 90c4038..c61df47 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -178,6 +178,7 @@ static int print_unex = 1;
 #include <linux/slab.h>
 #include <linux/mm.h>
 #include <linux/bio.h>
+#include <linux/smp_lock.h>
 #include <linux/string.h>
 #include <linux/jiffies.h>
 #include <linux/fcntl.h>
@@ -3593,6 +3594,18 @@ static int fd_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
 	return 0;
 }
 
+static int fd_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long param)
+{
+	int ret;
+
+	lock_kernel();
+	ret = fd_ioctl(bdev, mode, cmd, param);
+	unlock_kernel();
+
+	return ret;
+}
+
 static void __init config_types(void)
 {
 	bool has_drive = false;
@@ -3893,7 +3906,7 @@ static const struct block_device_operations floppy_fops = {
 	.owner			= THIS_MODULE,
 	.open			= floppy_open,
 	.release		= floppy_release,
-	.locked_ioctl		= fd_ioctl,
+	.ioctl			= fd_unlocked_ioctl,
 	.getgeo			= fd_getgeo,
 	.media_changed		= check_floppy_change,
 	.revalidate_disk	= floppy_revalidate,
diff --git a/drivers/block/nbd.c b/drivers/block/nbd.c
index 218d091..9789907 100644
--- a/drivers/block/nbd.c
+++ b/drivers/block/nbd.c
@@ -24,6 +24,7 @@
 #include <linux/errno.h>
 #include <linux/file.h>
 #include <linux/ioctl.h>
+#include <linux/smp_lock.h>
 #include <linux/compiler.h>
 #include <linux/err.h>
 #include <linux/kernel.h>
@@ -716,9 +717,11 @@ static int nbd_ioctl(struct block_device *bdev, fmode_t mode,
 	dprintk(DBG_IOCTL, "%s: nbd_ioctl cmd=%s(0x%x) arg=%lu\n",
 			lo->disk->disk_name, ioctl_cmd_to_ascii(cmd), cmd, arg);
 
+	lock_kernel();
 	mutex_lock(&lo->tx_lock);
 	error = __nbd_ioctl(bdev, lo, cmd, arg);
 	mutex_unlock(&lo->tx_lock);
+	unlock_kernel();
 
 	return error;
 }
@@ -726,7 +729,7 @@ static int nbd_ioctl(struct block_device *bdev, fmode_t mode,
 static const struct block_device_operations nbd_fops =
 {
 	.owner =	THIS_MODULE,
-	.locked_ioctl =	nbd_ioctl,
+	.ioctl =	nbd_ioctl,
 };
 
 /*
diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
index 71acf4e..daba7a6 100644
--- a/drivers/block/paride/pcd.c
+++ b/drivers/block/paride/pcd.c
@@ -138,6 +138,7 @@ enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_DLY};
 #include <linux/cdrom.h>
 #include <linux/spinlock.h>
 #include <linux/blkdev.h>
+#include <linux/smp_lock.h>
 #include <asm/uaccess.h>
 
 static DEFINE_SPINLOCK(pcd_lock);
@@ -238,7 +239,13 @@ static int pcd_block_ioctl(struct block_device *bdev, fmode_t mode,
 				unsigned cmd, unsigned long arg)
 {
 	struct pcd_unit *cd = bdev->bd_disk->private_data;
-	return cdrom_ioctl(&cd->info, bdev, mode, cmd, arg);
+	int ret;
+
+	lock_kernel();
+	ret = cdrom_ioctl(&cd->info, bdev, mode, cmd, arg);
+	unlock_kernel();
+
+	return ret;
 }
 
 static int pcd_block_media_changed(struct gendisk *disk)
@@ -251,7 +258,7 @@ static const struct block_device_operations pcd_bdops = {
 	.owner		= THIS_MODULE,
 	.open		= pcd_block_open,
 	.release	= pcd_block_release,
-	.locked_ioctl	= pcd_block_ioctl,
+	.ioctl		= pcd_block_ioctl,
 	.media_changed	= pcd_block_media_changed,
 };
 
diff --git a/drivers/block/paride/pd.c b/drivers/block/paride/pd.c
index c1e5cd0..b22943a 100644
--- a/drivers/block/paride/pd.c
+++ b/drivers/block/paride/pd.c
@@ -153,6 +153,7 @@ enum {D_PRT, D_PRO, D_UNI, D_MOD, D_GEO, D_SBY, D_DLY, D_SLV};
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
 #include <linux/kernel.h>
+#include <linux/smp_lock.h>
 #include <asm/uaccess.h>
 #include <linux/workqueue.h>
 
@@ -768,8 +769,10 @@ static int pd_ioctl(struct block_device *bdev, fmode_t mode,
 
 	switch (cmd) {
 	case CDROMEJECT:
+		lock_kernel();
 		if (disk->access == 1)
 			pd_special_command(disk, pd_eject);
+		unlock_kernel();
 		return 0;
 	default:
 		return -EINVAL;
@@ -812,7 +815,7 @@ static const struct block_device_operations pd_fops = {
 	.owner		= THIS_MODULE,
 	.open		= pd_open,
 	.release	= pd_release,
-	.locked_ioctl	= pd_ioctl,
+	.ioctl		= pd_ioctl,
 	.getgeo		= pd_getgeo,
 	.media_changed	= pd_check_media,
 	.revalidate_disk= pd_revalidate
diff --git a/drivers/block/paride/pf.c b/drivers/block/paride/pf.c
index c059aab..38b4d56 100644
--- a/drivers/block/paride/pf.c
+++ b/drivers/block/paride/pf.c
@@ -152,6 +152,7 @@ enum {D_PRT, D_PRO, D_UNI, D_MOD, D_SLV, D_LUN, D_DLY};
 #include <linux/spinlock.h>
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
+#include <linux/smp_lock.h>
 #include <asm/uaccess.h>
 
 static DEFINE_SPINLOCK(pf_spin_lock);
@@ -266,7 +267,7 @@ static const struct block_device_operations pf_fops = {
 	.owner		= THIS_MODULE,
 	.open		= pf_open,
 	.release	= pf_release,
-	.locked_ioctl	= pf_ioctl,
+	.ioctl		= pf_ioctl,
 	.getgeo		= pf_getgeo,
 	.media_changed	= pf_check_media,
 };
@@ -342,7 +343,10 @@ static int pf_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, u
 
 	if (pf->access != 1)
 		return -EBUSY;
+	lock_kernel();
 	pf_eject(pf);
+	unlock_kernel();
+
 	return 0;
 }
 
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 8a549db..1f70aec 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -57,6 +57,7 @@
 #include <linux/seq_file.h>
 #include <linux/miscdevice.h>
 #include <linux/freezer.h>
+#include <linux/smp_lock.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <scsi/scsi_cmnd.h>
@@ -2762,10 +2763,12 @@ out_mem:
 static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg)
 {
 	struct pktcdvd_device *pd = bdev->bd_disk->private_data;
+	int ret;
 
 	VPRINTK("pkt_ioctl: cmd %x, dev %d:%d\n", cmd,
 		MAJOR(bdev->bd_dev), MINOR(bdev->bd_dev));
 
+	lock_kernel();
 	switch (cmd) {
 	case CDROMEJECT:
 		/*
@@ -2783,12 +2786,14 @@ static int pkt_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd,
 	case CDROM_LAST_WRITTEN:
 	case CDROM_SEND_PACKET:
 	case SCSI_IOCTL_SEND_COMMAND:
-		return __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
+		ret = __blkdev_driver_ioctl(pd->bdev, mode, cmd, arg);
+		break;
 
 	default:
 		VPRINTK(DRIVER_NAME": Unknown ioctl for %s (%x)\n", pd->name, cmd);
-		return -ENOTTY;
+		ret = -ENOTTY;
 	}
+	unlock_kernel();
 
 	return 0;
 }
@@ -2812,7 +2817,7 @@ static const struct block_device_operations pktcdvd_ops = {
 	.owner =		THIS_MODULE,
 	.open =			pkt_open,
 	.release =		pkt_close,
-	.locked_ioctl =		pkt_ioctl,
+	.ioctl =		pkt_ioctl,
 	.media_changed =	pkt_media_changed,
 };
 
diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index e463657..f04f74e 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -20,6 +20,7 @@
 #include <linux/fd.h>
 #include <linux/slab.h>
 #include <linux/blkdev.h>
+#include <linux/smp_lock.h>
 #include <linux/hdreg.h>
 #include <linux/kernel.h>
 #include <linux/delay.h>
@@ -690,7 +691,9 @@ static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
 	case FDEJECT:
 		if (fs->ref_count != 1)
 			return -EBUSY;
+		lock_kernel();
 		err = floppy_eject(fs);
+		unlock_kernel();
 		return err;
 
 	case FDGETPRM:
@@ -753,7 +756,7 @@ static const struct block_device_operations floppy_fops = {
 	.owner		 = THIS_MODULE,
 	.open		 = floppy_open,
 	.release	 = floppy_release,
-	.locked_ioctl	 = floppy_ioctl,
+	.ioctl		 = floppy_ioctl,
 	.getgeo		 = floppy_getgeo,
 	.media_changed	 = floppy_check_change,
 	.revalidate_disk = floppy_revalidate,
diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c
index 52f2d11..4a83540 100644
--- a/drivers/block/swim3.c
+++ b/drivers/block/swim3.c
@@ -25,6 +25,7 @@
 #include <linux/ioctl.h>
 #include <linux/blkdev.h>
 #include <linux/interrupt.h>
+#include <linux/smp_lock.h>
 #include <linux/module.h>
 #include <linux/spinlock.h>
 #include <asm/io.h>
@@ -867,6 +868,18 @@ static int floppy_ioctl(struct block_device *bdev, fmode_t mode,
 	return -ENOTTY;
 }
 
+static int floppy_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+				 unsigned int cmd, unsigned long param)
+{
+	int ret;
+
+	lock_kernel();
+	ret = floppy_ioctl(bdev, mode, cmd, param);
+	unlock_kernel();
+
+	return ret;
+}
+
 static int floppy_open(struct block_device *bdev, fmode_t mode)
 {
 	struct floppy_state *fs = bdev->bd_disk->private_data;
@@ -997,7 +1010,7 @@ static int floppy_revalidate(struct gendisk *disk)
 static const struct block_device_operations floppy_fops = {
 	.open		= floppy_open,
 	.release	= floppy_release,
-	.locked_ioctl	= floppy_ioctl,
+	.ioctl		= floppy_unlocked_ioctl,
 	.media_changed	= floppy_check_change,
 	.revalidate_disk= floppy_revalidate,
 };
diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index 0536b5b..d6e14d2 100644
--- a/drivers/block/ub.c
+++ b/drivers/block/ub.c
@@ -28,6 +28,7 @@
 #include <linux/timer.h>
 #include <linux/scatterlist.h>
 #include <linux/slab.h>
+#include <linux/smp_lock.h>
 #include <scsi/scsi.h>
 
 #define DRV_NAME "ub"
@@ -1729,8 +1730,13 @@ static int ub_bd_ioctl(struct block_device *bdev, fmode_t mode,
 {
 	struct gendisk *disk = bdev->bd_disk;
 	void __user *usermem = (void __user *) arg;
+	int ret;
+
+	lock_kernel();
+	ret = scsi_cmd_ioctl(disk->queue, disk, mode, cmd, usermem);
+	unlock_kernel();
 
-	return scsi_cmd_ioctl(disk->queue, disk, mode, cmd, usermem);
+	return ret;
 }
 
 /*
@@ -1794,7 +1800,7 @@ static const struct block_device_operations ub_bd_fops = {
 	.owner		= THIS_MODULE,
 	.open		= ub_bd_open,
 	.release	= ub_bd_release,
-	.locked_ioctl	= ub_bd_ioctl,
+	.ioctl		= ub_bd_ioctl,
 	.media_changed	= ub_bd_media_changed,
 	.revalidate_disk = ub_bd_revalidate,
 };
diff --git a/drivers/block/virtio_blk.c b/drivers/block/virtio_blk.c
index 83fa09a..a0f9383 100644
--- a/drivers/block/virtio_blk.c
+++ b/drivers/block/virtio_blk.c
@@ -2,6 +2,7 @@
 #include <linux/spinlock.h>
 #include <linux/slab.h>
 #include <linux/blkdev.h>
+#include <linux/smp_lock.h>
 #include <linux/hdreg.h>
 #include <linux/virtio.h>
 #include <linux/virtio_blk.h>
@@ -245,6 +246,18 @@ static int virtblk_ioctl(struct block_device *bdev, fmode_t mode,
 			      (void __user *)data);
 }
 
+static int virtblk_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long param)
+{
+	int ret;
+
+	lock_kernel();
+	ret = virtblk_ioctl(bdev, mode, cmd, param);
+	unlock_kernel();
+
+	return ret;
+}
+
 /* We provide getgeo only to please some old bootloader/partitioning tools */
 static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
 {
@@ -271,7 +284,7 @@ static int virtblk_getgeo(struct block_device *bd, struct hd_geometry *geo)
 }
 
 static const struct block_device_operations virtblk_fops = {
-	.locked_ioctl = virtblk_ioctl,
+	.ioctl  = virtblk_unlocked_ioctl,
 	.owner  = THIS_MODULE,
 	.getgeo = virtblk_getgeo,
 };
diff --git a/drivers/block/xd.c b/drivers/block/xd.c
index 18a80ff..7f00543 100644
--- a/drivers/block/xd.c
+++ b/drivers/block/xd.c
@@ -46,6 +46,7 @@
 #include <linux/init.h>
 #include <linux/wait.h>
 #include <linux/blkdev.h>
+#include <linux/smp_lock.h>
 #include <linux/blkpg.h>
 #include <linux/delay.h>
 #include <linux/io.h>
@@ -133,7 +134,7 @@ static int xd_getgeo(struct block_device *bdev, struct hd_geometry *geo);
 
 static const struct block_device_operations xd_fops = {
 	.owner	= THIS_MODULE,
-	.locked_ioctl	= xd_ioctl,
+	.ioctl	= xd_unlocked_ioctl,
 	.getgeo = xd_getgeo,
 };
 static DECLARE_WAIT_QUEUE_HEAD(xd_wait_int);
@@ -375,6 +376,18 @@ static int xd_ioctl(struct block_device *bdev, fmode_t mode, u_int cmd, u_long a
 	}
 }
 
+static int xd_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long param)
+{
+	int ret;
+
+	lock_kernel();
+	ret = xd_ioctl(bdev, mode, cmd, param);
+	unlock_kernel();
+
+	return ret;
+}
+
 /* xd_readwrite: handle a read/write request */
 static int xd_readwrite (u_char operation,XD_INFO *p,char *buffer,u_int block,u_int count)
 {
diff --git a/drivers/block/xd.h b/drivers/block/xd.h
index 37cacef..bded505 100644
--- a/drivers/block/xd.h
+++ b/drivers/block/xd.h
@@ -105,7 +105,7 @@ static u_char xd_detect (u_char *controller, unsigned int *address);
 static u_char xd_initdrives (void (*init_drive)(u_char drive));
 
 static void do_xd_request (struct request_queue * q);
-static int xd_ioctl (struct block_device *bdev,fmode_t mode,unsigned int cmd,unsigned long arg);
+static int xd_unlocked_ioctl (struct block_device *bdev,fmode_t mode,unsigned int cmd,unsigned long arg);
 static int xd_readwrite (u_char operation,XD_INFO *disk,char *buffer,u_int block,u_int count);
 static void xd_recalibrate (u_char drive);
 
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 82ed403..96a70bb 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -1046,7 +1046,7 @@ static const struct block_device_operations xlvbd_block_fops =
 	.open = blkif_open,
 	.release = blkif_release,
 	.getgeo = blkif_getgeo,
-	.locked_ioctl = blkif_ioctl,
+	.ioctl = blkif_ioctl,
 };
 
 
diff --git a/drivers/cdrom/gdrom.c b/drivers/cdrom/gdrom.c
index 03c71f7..7d7b894 100644
--- a/drivers/cdrom/gdrom.c
+++ b/drivers/cdrom/gdrom.c
@@ -32,6 +32,7 @@
 #include <linux/blkdev.h>
 #include <linux/interrupt.h>
 #include <linux/device.h>
+#include <linux/smp_lock.h>
 #include <linux/wait.h>
 #include <linux/workqueue.h>
 #include <linux/platform_device.h>
@@ -509,7 +510,13 @@ static int gdrom_bdops_mediachanged(struct gendisk *disk)
 static int gdrom_bdops_ioctl(struct block_device *bdev, fmode_t mode,
 	unsigned cmd, unsigned long arg)
 {
-	return cdrom_ioctl(gd.cd_info, bdev, mode, cmd, arg);
+	int ret;
+
+	lock_kernel();
+	ret = cdrom_ioctl(gd.cd_info, bdev, mode, cmd, arg);
+	unlock_kernel();
+
+	return ret;
 }
 
 static const struct block_device_operations gdrom_bdops = {
@@ -517,7 +524,7 @@ static const struct block_device_operations gdrom_bdops = {
 	.open			= gdrom_bdops_open,
 	.release		= gdrom_bdops_release,
 	.media_changed		= gdrom_bdops_mediachanged,
-	.locked_ioctl		= gdrom_bdops_ioctl,
+	.ioctl			= gdrom_bdops_ioctl,
 };
 
 static irqreturn_t gdrom_command_interrupt(int irq, void *dev_id)
diff --git a/drivers/cdrom/viocd.c b/drivers/cdrom/viocd.c
index 451cd70..203c87c 100644
--- a/drivers/cdrom/viocd.c
+++ b/drivers/cdrom/viocd.c
@@ -40,6 +40,7 @@
 #include <linux/module.h>
 #include <linux/completion.h>
 #include <linux/proc_fs.h>
+#include <linux/smp_lock.h>
 #include <linux/seq_file.h>
 #include <linux/scatterlist.h>
 
@@ -168,7 +169,13 @@ static int viocd_blk_ioctl(struct block_device *bdev, fmode_t mode,
 		unsigned cmd, unsigned long arg)
 {
 	struct disk_info *di = bdev->bd_disk->private_data;
-	return cdrom_ioctl(&di->viocd_info, bdev, mode, cmd, arg);
+	int ret;
+
+	lock_kernel();
+	ret = cdrom_ioctl(&di->viocd_info, bdev, mode, cmd, arg);
+	unlock_kernel();
+
+	return ret;
 }
 
 static int viocd_blk_media_changed(struct gendisk *disk)
@@ -181,7 +188,7 @@ static const struct block_device_operations viocd_fops = {
 	.owner =		THIS_MODULE,
 	.open =			viocd_blk_open,
 	.release =		viocd_blk_release,
-	.locked_ioctl =		viocd_blk_ioctl,
+	.ioctl =		viocd_blk_ioctl,
 	.media_changed =	viocd_blk_media_changed,
 };
 
diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
index 64207df..03c93ae 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -31,6 +31,7 @@
 #include <linux/delay.h>
 #include <linux/timer.h>
 #include <linux/seq_file.h>
+#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include <linux/errno.h>
@@ -1670,6 +1671,19 @@ static int idecd_ioctl(struct block_device *bdev, fmode_t mode,
 	return err;
 }
 
+static int idecd_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long arg)
+{
+	int ret;
+
+	lock_kernel();
+	ret = idecd_ioctl(bdev, mode, cmd, arg);
+	unlock_kernel();
+
+	return ret;
+}
+
+
 static int idecd_media_changed(struct gendisk *disk)
 {
 	struct cdrom_info *info = ide_drv_g(disk, cdrom_info);
@@ -1690,7 +1704,7 @@ static const struct block_device_operations idecd_ops = {
 	.owner			= THIS_MODULE,
 	.open			= idecd_open,
 	.release		= idecd_release,
-	.locked_ioctl		= idecd_ioctl,
+	.ioctl			= idecd_unlocked_ioctl,
 	.media_changed		= idecd_media_changed,
 	.revalidate_disk	= idecd_revalidate_disk
 };
diff --git a/drivers/ide/ide-disk_ioctl.c b/drivers/ide/ide-disk_ioctl.c
index 7b783dd..ec94c66 100644
--- a/drivers/ide/ide-disk_ioctl.c
+++ b/drivers/ide/ide-disk_ioctl.c
@@ -1,6 +1,7 @@
 #include <linux/kernel.h>
 #include <linux/ide.h>
 #include <linux/hdreg.h>
+#include <linux/smp_lock.h>
 
 #include "ide-disk.h"
 
@@ -18,9 +19,13 @@ int ide_disk_ioctl(ide_drive_t *drive, struct block_device *bdev, fmode_t mode,
 {
 	int err;
 
+	lock_kernel();
 	err = ide_setting_ioctl(drive, bdev, cmd, arg, ide_disk_ioctl_settings);
 	if (err != -EOPNOTSUPP)
-		return err;
+		goto out;
 
-	return generic_ide_ioctl(drive, bdev, cmd, arg);
+	err = generic_ide_ioctl(drive, bdev, cmd, arg);
+out:
+	unlock_kernel();
+	return err;
 }
diff --git a/drivers/ide/ide-floppy_ioctl.c b/drivers/ide/ide-floppy_ioctl.c
index 9c22882..fd3d05a 100644
--- a/drivers/ide/ide-floppy_ioctl.c
+++ b/drivers/ide/ide-floppy_ioctl.c
@@ -5,6 +5,7 @@
 #include <linux/kernel.h>
 #include <linux/ide.h>
 #include <linux/cdrom.h>
+#include <linux/smp_lock.h>
 
 #include <asm/unaligned.h>
 
@@ -275,12 +276,15 @@ int ide_floppy_ioctl(ide_drive_t *drive, struct block_device *bdev,
 	void __user *argp = (void __user *)arg;
 	int err;
 
-	if (cmd == CDROMEJECT || cmd == CDROM_LOCKDOOR)
-		return ide_floppy_lockdoor(drive, &pc, arg, cmd);
+	lock_kernel();
+	if (cmd == CDROMEJECT || cmd == CDROM_LOCKDOOR) {
+		err = ide_floppy_lockdoor(drive, &pc, arg, cmd);
+		goto out;
+	}
 
 	err = ide_floppy_format_ioctl(drive, &pc, mode, cmd, argp);
 	if (err != -ENOTTY)
-		return err;
+		goto out;
 
 	/*
 	 * skip SCSI_IOCTL_SEND_COMMAND (deprecated)
@@ -293,5 +297,7 @@ int ide_floppy_ioctl(ide_drive_t *drive, struct block_device *bdev,
 	if (err == -ENOTTY)
 		err = generic_ide_ioctl(drive, bdev, cmd, arg);
 
+out:
+	unlock_kernel();
 	return err;
 }
diff --git a/drivers/ide/ide-gd.c b/drivers/ide/ide-gd.c
index c102d23..883f0c9 100644
--- a/drivers/ide/ide-gd.c
+++ b/drivers/ide/ide-gd.c
@@ -323,7 +323,7 @@ static const struct block_device_operations ide_gd_ops = {
 	.owner			= THIS_MODULE,
 	.open			= ide_gd_open,
 	.release		= ide_gd_release,
-	.locked_ioctl		= ide_gd_ioctl,
+	.ioctl			= ide_gd_ioctl,
 	.getgeo			= ide_gd_getgeo,
 	.media_changed		= ide_gd_media_changed,
 	.unlock_native_capacity	= ide_gd_unlock_native_capacity,
diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index b072328..2487916 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -32,6 +32,7 @@
 #include <linux/errno.h>
 #include <linux/genhd.h>
 #include <linux/seq_file.h>
+#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <linux/pci.h>
 #include <linux/ide.h>
@@ -1926,9 +1927,14 @@ static int idetape_ioctl(struct block_device *bdev, fmode_t mode,
 {
 	struct ide_tape_obj *tape = ide_drv_g(bdev->bd_disk, ide_tape_obj);
 	ide_drive_t *drive = tape->drive;
-	int err = generic_ide_ioctl(drive, bdev, cmd, arg);
+	int err;
+
+	lock_kernel();
+	err = generic_ide_ioctl(drive, bdev, cmd, arg);
 	if (err == -EINVAL)
 		err = idetape_blkdev_ioctl(drive, cmd, arg);
+	unlock_kernel();
+
 	return err;
 }
 
@@ -1936,7 +1942,7 @@ static const struct block_device_operations idetape_block_ops = {
 	.owner		= THIS_MODULE,
 	.open		= idetape_open,
 	.release	= idetape_release,
-	.locked_ioctl	= idetape_ioctl,
+	.ioctl		= idetape_ioctl,
 };
 
 static int ide_tape_probe(ide_drive_t *drive)
diff --git a/drivers/message/i2o/i2o_block.c b/drivers/message/i2o/i2o_block.c
index fc593fb..1f3b080 100644
--- a/drivers/message/i2o/i2o_block.c
+++ b/drivers/message/i2o/i2o_block.c
@@ -53,6 +53,7 @@
 #include <linux/module.h>
 #include <linux/slab.h>
 #include <linux/i2o.h>
+#include <linux/smp_lock.h>
 
 #include <linux/mempool.h>
 
@@ -678,6 +679,18 @@ static int i2o_block_ioctl(struct block_device *bdev, fmode_t mode,
 	return -ENOTTY;
 };
 
+static int i2o_block_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long arg)
+{
+	int ret;
+
+	lock_kernel();
+	ret = i2o_block_ioctl(bdev, mode, cmd, arg);
+	unlock_kernel();
+
+	return ret;
+}
+
 /**
  *	i2o_block_media_changed - Have we seen a media change?
  *	@disk: gendisk which should be verified
@@ -930,7 +943,7 @@ static const struct block_device_operations i2o_block_fops = {
 	.owner = THIS_MODULE,
 	.open = i2o_block_open,
 	.release = i2o_block_release,
-	.locked_ioctl = i2o_block_ioctl,
+	.ioctl = i2o_block_unlocked_ioctl,
 	.getgeo = i2o_block_getgeo,
 	.media_changed = i2o_block_media_changed
 };
diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 03e19c1..3ddc95b 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -15,6 +15,7 @@
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
 #include <linux/spinlock.h>
+#include <linux/smp_lock.h>
 #include <linux/hdreg.h>
 #include <linux/init.h>
 #include <linux/mutex.h>
@@ -237,6 +238,7 @@ static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
 	if (!dev)
 		return ret;
 
+	lock_kernel();
 	mutex_lock(&dev->lock);
 
 	if (!dev->mtd)
@@ -250,6 +252,7 @@ static int blktrans_ioctl(struct block_device *bdev, fmode_t mode,
 	}
 unlock:
 	mutex_unlock(&dev->lock);
+	unlock_kernel();
 	blktrans_dev_put(dev);
 	return ret;
 }
@@ -258,7 +261,7 @@ static const struct block_device_operations mtd_blktrans_ops = {
 	.owner		= THIS_MODULE,
 	.open		= blktrans_open,
 	.release	= blktrans_release,
-	.locked_ioctl	= blktrans_ioctl,
+	.ioctl		= blktrans_ioctl,
 	.getgeo		= blktrans_getgeo,
 };
 
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 829cc37..858c89d 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -46,6 +46,7 @@
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
 #include <linux/delay.h>
+#include <linux/smp_lock.h>
 #include <linux/mutex.h>
 #include <linux/string_helpers.h>
 #include <linux/async.h>
@@ -914,6 +915,18 @@ static int sd_ioctl(struct block_device *bdev, fmode_t mode,
 	return scsi_ioctl(sdp, cmd, p);
 }
 
+static int sd_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+			     unsigned int cmd, unsigned long arg)
+{
+	int ret;
+
+	lock_kernel();
+	ret = sd_ioctl(bdev, mode, cmd, arg);
+	unlock_kernel();
+
+	return ret;
+}
+
 static void set_media_not_present(struct scsi_disk *sdkp)
 {
 	sdkp->media_present = 0;
@@ -1094,7 +1107,7 @@ static const struct block_device_operations sd_fops = {
 	.owner			= THIS_MODULE,
 	.open			= sd_open,
 	.release		= sd_release,
-	.locked_ioctl		= sd_ioctl,
+	.ioctl			= sd_unlocked_ioctl,
 	.getgeo			= sd_getgeo,
 #ifdef CONFIG_COMPAT
 	.compat_ioctl		= sd_compat_ioctl,
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 0a90abc..ad62aa8 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -44,6 +44,7 @@
 #include <linux/init.h>
 #include <linux/blkdev.h>
 #include <linux/mutex.h>
+#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <asm/uaccess.h>
 
@@ -520,6 +521,18 @@ static int sr_block_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 	return scsi_ioctl(sdev, cmd, argp);
 }
 
+static int sr_block_unlocked_ioctl(struct block_device *bdev, fmode_t mode,
+				   unsigned int cmd, unsigned long arg)
+{
+	int ret;
+
+	lock_kernel();
+	ret = sr_block_ioctl(bdev, mode, cmd, arg);
+	unlock_kernel();
+
+	return ret;
+}
+
 static int sr_block_media_changed(struct gendisk *disk)
 {
 	struct scsi_cd *cd = scsi_cd(disk);
@@ -531,7 +544,7 @@ static const struct block_device_operations sr_bdops =
 	.owner		= THIS_MODULE,
 	.open		= sr_block_open,
 	.release	= sr_block_release,
-	.locked_ioctl	= sr_block_ioctl,
+	.ioctl		= sr_block_unlocked_ioctl,
 	.media_changed	= sr_block_media_changed,
 	/* 
 	 * No compat_ioctl for now because sr_block_ioctl never
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 8b7f5e0..e947688 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1324,7 +1324,6 @@ static inline int blk_integrity_rq(struct request *rq)
 struct block_device_operations {
 	int (*open) (struct block_device *, fmode_t);
 	int (*release) (struct gendisk *, fmode_t);
-	int (*locked_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	int (*ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	int (*compat_ioctl) (struct block_device *, fmode_t, unsigned, unsigned long);
 	int (*direct_access) (struct block_device *, sector_t,
-- 
1.7.0.4


^ permalink raw reply related	[flat|nested] 5+ messages in thread

* Re: [PATCH] block: push down BKL into .locked_ioctl
  2010-06-01 22:43   ` [PATCH] block: push down BKL into .locked_ioctl Arnd Bergmann
@ 2010-06-02 10:16     ` Christoph Hellwig
  2010-06-02 14:46       ` [PATCH] block: push down BKL into .open and .release Arnd Bergmann
  0 siblings, 1 reply; 5+ messages in thread
From: Christoph Hellwig @ 2010-06-02 10:16 UTC (permalink / raw)
  To: Arnd Bergmann
  Cc: Christoph Hellwig, Jens Axboe, Vivek Goyal, Tejun Heo,
	Frederic Weisbecker, FUJITA Tomonori, Martin K. Petersen,
	Steven Rostedt, Douglas Gilbert, Ingo Molnar, John Kacur,
	linux-scsi, linux-kernel

> Ok, here comes the first step. Can you be more specific
> about what you mean with the open and release methods? 
> Do you mean the sg.c and bsg.c chrdev file operations?

No, the open and release methods in struct block_device_operations.
After this the driver API for block devices is BKL free, which
is an important step.  To get there the locking in blkdev_get/put
needs to be sorted out first, though.


The ioctl pushdown patch looks good to me, btw.


^ permalink raw reply	[flat|nested] 5+ messages in thread

* [PATCH] block: push down BKL into .open and .release
  2010-06-02 10:16     ` Christoph Hellwig
@ 2010-06-02 14:46       ` Arnd Bergmann
  0 siblings, 0 replies; 5+ messages in thread
From: Arnd Bergmann @ 2010-06-02 14:46 UTC (permalink / raw)
  To: Christoph Hellwig
  Cc: Jens Axboe, Vivek Goyal, Tejun Heo, Frederic Weisbecker,
	FUJITA Tomonori, Martin K. Petersen, Steven Rostedt,
	Douglas Gilbert, Ingo Molnar, John Kacur, linux-scsi,
	linux-kernel

The open and release block_device_operations are currently
called with the BKL held. In order to change that, we must
first make sure that all drivers that currently rely
on this have no regressions.

This blindly pushes the BKL into all .open and .release
operations for all block drivers to prepare for the
next step. The drivers can subsequently replace the BKL
with their own locks or remove it completely when it can
be shown that it is not needed.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
On Wednesday 02 June 2010, Christoph Hellwig wrote:
> > Ok, here comes the first step. Can you be more specific
> > about what you mean with the open and release methods? 
> > Do you mean the sg.c and bsg.c chrdev file operations?
> 
> No, the open and release methods in struct block_device_operations.
> After this the driver API for block devices is BKL free, which
> is an important step.  To get there the locking in blkdev_get/put
> needs to be sorted out first, though.

I see. I hoped that I could get around fixing the blkdev_get/put
locking, since I'm not really familiar with that code.
Maybe someone else can step in for that. I can certainly do
the patch to add the BKL to all open/release block_device_operations,
which does not require deep understanding of what is actually
getting locked.

> The ioctl pushdown patch looks good to me, btw.

ok.

	Arnd
---

 arch/um/drivers/ubd_kern.c          |    7 ++++++-
 drivers/block/DAC960.c              |   13 +++++++++----
 drivers/block/amiflop.c             |   12 ++++++++++--
 drivers/block/aoe/aoeblk.c          |    3 +++
 drivers/block/ataflop.c             |   14 +++++++++++++-
 drivers/block/cciss.c               |   24 ++++++++++++++++++++----
 drivers/block/cpqarray.c            |   22 +++++++++++++++++++---
 drivers/block/drbd/drbd_main.c      |    4 ++++
 drivers/block/floppy.c              |    5 +++++
 drivers/block/loop.c                |    5 +++++
 drivers/block/paride/pcd.c          |   10 +++++++++-
 drivers/block/paride/pd.c           |    4 ++++
 drivers/block/paride/pf.c           |   20 +++++++++++++++-----
 drivers/block/pktcdvd.c             |    5 +++++
 drivers/block/swim.c                |   15 ++++++++++++++-
 drivers/block/swim3.c               |   15 ++++++++++++++-
 drivers/block/ub.c                  |   17 ++++++++++++++++-
 drivers/block/viodasd.c             |   19 ++++++++++++++++++-
 drivers/block/xen-blkfront.c        |    7 +++++++
 drivers/block/xsysace.c             |    6 ++++++
 drivers/block/z2ram.c               |   13 ++++++++++---
 drivers/cdrom/gdrom.c               |    8 +++++++-
 drivers/cdrom/viocd.c               |   10 +++++++++-
 drivers/ide/ide-cd.c                |   14 +++++++++-----
 drivers/ide/ide-gd.c                |   17 ++++++++++++++++-
 drivers/ide/ide-tape.c              |    9 ++++++++-
 drivers/md/dm.c                     |    7 +++++++
 drivers/md/md.c                     |    6 ++++++
 drivers/memstick/core/mspro_block.c |    9 ++++++++-
 drivers/message/i2o/i2o_block.c     |    4 ++++
 drivers/mmc/card/block.c            |    5 +++++
 drivers/mtd/mtd_blkdevs.c           |    6 +++++-
 drivers/s390/block/dasd.c           |    6 ++++++
 drivers/s390/block/dcssblk.c        |    5 +++++
 drivers/s390/char/tape_block.c      |    8 +++++++-
 drivers/scsi/sd.c                   |    5 +++++
 drivers/scsi/sr.c                   |    7 ++++++-
 drivers/staging/hv/blkvsc_drv.c     |    5 +++++
 38 files changed, 330 insertions(+), 41 deletions(-)

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index da992a3..1bcd208 100644
--- a/arch/um/drivers/ubd_kern.c
+++ b/arch/um/drivers/ubd_kern.c
@@ -33,6 +33,7 @@
 #include "linux/mm.h"
 #include "linux/slab.h"
 #include "linux/vmalloc.h"
+#include "linux/smp_lock.h"
 #include "linux/blkpg.h"
 #include "linux/genhd.h"
 #include "linux/spinlock.h"
@@ -1098,6 +1099,7 @@ static int ubd_open(struct block_device *bdev, fmode_t mode)
 	struct ubd *ubd_dev = disk->private_data;
 	int err = 0;
 
+	lock_kernel();
 	if(ubd_dev->count == 0){
 		err = ubd_open_dev(ubd_dev);
 		if(err){
@@ -1115,7 +1117,8 @@ static int ubd_open(struct block_device *bdev, fmode_t mode)
 	        if(--ubd_dev->count == 0) ubd_close_dev(ubd_dev);
 	        err = -EROFS;
 	}*/
- out:
+out:
+	unlock_kernel();
 	return err;
 }
 
@@ -1123,8 +1126,10 @@ static int ubd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct ubd *ubd_dev = disk->private_data;
 
+	lock_kernel();
 	if(--ubd_dev->count == 0)
 		ubd_close_dev(ubd_dev);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/block/DAC960.c b/drivers/block/DAC960.c
index c5f22bb..4e2c367 100644
--- a/drivers/block/DAC960.c
+++ b/drivers/block/DAC960.c
@@ -79,23 +79,28 @@ static int DAC960_open(struct block_device *bdev, fmode_t mode)
 	struct gendisk *disk = bdev->bd_disk;
 	DAC960_Controller_T *p = disk->queue->queuedata;
 	int drive_nr = (long)disk->private_data;
+	int ret = -ENXIO;
 
+	lock_kernel();
 	if (p->FirmwareType == DAC960_V1_Controller) {
 		if (p->V1.LogicalDriveInformation[drive_nr].
 		    LogicalDriveState == DAC960_V1_LogicalDrive_Offline)
-			return -ENXIO;
+			goto out;
 	} else {
 		DAC960_V2_LogicalDeviceInfo_T *i =
 			p->V2.LogicalDeviceInformation[drive_nr];
 		if (!i || i->LogicalDeviceState == DAC960_V2_LogicalDevice_Offline)
-			return -ENXIO;
+			goto out;
 	}
 
 	check_disk_change(bdev);
 
 	if (!get_capacity(p->disks[drive_nr]))
-		return -ENXIO;
-	return 0;
+		goto out;
+	ret = 0;
+out:
+	unlock_kernel();
+	return ret;
 }
 
 static int DAC960_getgeo(struct block_device *bdev, struct hd_geometry *geo)
diff --git a/drivers/block/amiflop.c b/drivers/block/amiflop.c
index 7a51535..8af7af7 100644
--- a/drivers/block/amiflop.c
+++ b/drivers/block/amiflop.c
@@ -1555,10 +1555,13 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	int old_dev;
 	unsigned long flags;
 
+	lock_kernel();
 	old_dev = fd_device[drive];
 
-	if (fd_ref[drive] && old_dev != system)
+	if (fd_ref[drive] && old_dev != system) {
+		unlock_kernel();
 		return -EBUSY;
+	}
 
 	if (mode & (FMODE_READ|FMODE_WRITE)) {
 		check_disk_change(bdev);
@@ -1571,8 +1574,10 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 			fd_deselect (drive);
 			rel_fdc();
 
-			if (wrprot)
+			if (wrprot) {
+				unlock_kernel();
 				return -EROFS;
+			}
 		}
 	}
 
@@ -1589,6 +1594,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	printk(KERN_INFO "fd%d: accessing %s-disk with %s-layout\n",drive,
 	       unit[drive].type->name, data_types[system].name);
 
+	unlock_kernel();
 	return 0;
 }
 
@@ -1597,6 +1603,7 @@ static int floppy_release(struct gendisk *disk, fmode_t mode)
 	struct amiga_floppy_struct *p = disk->private_data;
 	int drive = p - unit;
 
+	lock_kernel();
 	if (unit[drive].dirty == 1) {
 		del_timer (flush_track_timer + drive);
 		non_int_flush_track (drive);
@@ -1610,6 +1617,7 @@ static int floppy_release(struct gendisk *disk, fmode_t mode)
 /* the mod_use counter is handled this way */
 	floppy_off (drive | 0x40000000);
 #endif
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/block/aoe/aoeblk.c b/drivers/block/aoe/aoeblk.c
index 035cefe..1fad4e4 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -124,13 +124,16 @@ aoeblk_open(struct block_device *bdev, fmode_t mode)
 	struct aoedev *d = bdev->bd_disk->private_data;
 	ulong flags;
 
+	lock_kernel();
 	spin_lock_irqsave(&d->lock, flags);
 	if (d->flags & DEVFL_UP) {
 		d->nopen++;
 		spin_unlock_irqrestore(&d->lock, flags);
+		unlock_kernel();
 		return 0;
 	}
 	spin_unlock_irqrestore(&d->lock, flags);
+	unlock_kernel();
 	return -ENODEV;
 }
 
diff --git a/drivers/block/ataflop.c b/drivers/block/ataflop.c
index 09ae46f..f3eb6d9 100644
--- a/drivers/block/ataflop.c
+++ b/drivers/block/ataflop.c
@@ -1850,22 +1850,34 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
+static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	lock_kernel();
+	ret = floppy_open(bdev, mode);
+	unlock_kernel();
+
+	return ret;
+}
 
 static int floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	struct atari_floppy_struct *p = disk->private_data;
+	lock_kernel();
 	if (p->ref < 0)
 		p->ref = 0;
 	else if (!p->ref--) {
 		printk(KERN_ERR "floppy_release with fd_ref == 0");
 		p->ref = 0;
 	}
+	unlock_kernel();
 	return 0;
 }
 
 static const struct block_device_operations floppy_fops = {
 	.owner		= THIS_MODULE,
-	.open		= floppy_open,
+	.open		= floppy_unlocked_open,
 	.release	= floppy_release,
 	.ioctl		= fd_unlocked_ioctl,
 	.media_changed	= check_floppy_change,
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index 6c3c8c4..5142d87 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -168,7 +168,7 @@ static LIST_HEAD(scan_q);
 
 static void do_cciss_request(struct request_queue *q);
 static irqreturn_t do_cciss_intr(int irq, void *dev_id);
-static int cciss_open(struct block_device *bdev, fmode_t mode);
+static int cciss_unlocked_open(struct block_device *bdev, fmode_t mode);
 static int cciss_release(struct gendisk *disk, fmode_t mode);
 static int do_ioctl(struct block_device *bdev, fmode_t mode,
 		    unsigned int cmd, unsigned long arg);
@@ -223,7 +223,7 @@ static int cciss_compat_ioctl(struct block_device *, fmode_t,
 
 static const struct block_device_operations cciss_fops = {
 	.owner = THIS_MODULE,
-	.open = cciss_open,
+	.open = cciss_unlocked_open,
 	.release = cciss_release,
 	.ioctl = do_ioctl,
 	.getgeo = cciss_getgeo,
@@ -1006,13 +1006,28 @@ static int cciss_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
+static int cciss_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	lock_kernel();
+	ret = cciss_open(bdev, mode);
+	unlock_kernel();
+
+	return ret;
+}
+
 /*
  * Close.  Sync first.
  */
 static int cciss_release(struct gendisk *disk, fmode_t mode)
 {
-	ctlr_info_t *host = get_host(disk);
-	drive_info_struct *drv = get_drv(disk);
+	ctlr_info_t *host;
+	drive_info_struct *drv;
+
+	lock_kernel();
+	host = get_host(disk);
+	drv = get_drv(disk);
 
 #ifdef CCISS_DEBUG
 	printk(KERN_DEBUG "cciss_release %s\n", disk->disk_name);
@@ -1020,6 +1035,7 @@ static int cciss_release(struct gendisk *disk, fmode_t mode)
 
 	drv->usage_count--;
 	host->usage_count--;
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/block/cpqarray.c b/drivers/block/cpqarray.c
index 072e57c..a0fad65 100644
--- a/drivers/block/cpqarray.c
+++ b/drivers/block/cpqarray.c
@@ -158,7 +158,7 @@ static int sendcmd(
 	unsigned int blkcnt,
 	unsigned int log_unit );
 
-static int ida_open(struct block_device *bdev, fmode_t mode);
+static int ida_unlocked_open(struct block_device *bdev, fmode_t mode);
 static int ida_release(struct gendisk *disk, fmode_t mode);
 static int ida_unlocked_ioctl(struct block_device *bdev, fmode_t mode, unsigned int cmd, unsigned long arg);
 static int ida_getgeo(struct block_device *bdev, struct hd_geometry *geo);
@@ -196,7 +196,7 @@ static inline ctlr_info_t *get_host(struct gendisk *disk)
 
 static const struct block_device_operations ida_fops  = {
 	.owner		= THIS_MODULE,
-	.open		= ida_open,
+	.open		= ida_unlocked_open,
 	.release	= ida_release,
 	.ioctl		= ida_unlocked_ioctl,
 	.getgeo		= ida_getgeo,
@@ -841,13 +841,29 @@ static int ida_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
+static int ida_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	lock_kernel();
+	ret = ida_open(bdev, mode);
+	unlock_kernel();
+
+	return ret;
+}
+
 /*
  * Close.  Sync first.
  */
 static int ida_release(struct gendisk *disk, fmode_t mode)
 {
-	ctlr_info_t *host = get_host(disk);
+	ctlr_info_t *host;
+
+	lock_kernel();
+	host = get_host(disk);
 	host->usage_count--;
+	unlock_kernel();
+
 	return 0;
 }
 
diff --git a/drivers/block/drbd/drbd_main.c b/drivers/block/drbd/drbd_main.c
index be2d2da..b46db3b 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2619,6 +2619,7 @@ static int drbd_open(struct block_device *bdev, fmode_t mode)
 	unsigned long flags;
 	int rv = 0;
 
+	lock_kernel();
 	spin_lock_irqsave(&mdev->req_lock, flags);
 	/* to have a stable mdev->state.role
 	 * and no race with updating open_cnt */
@@ -2633,6 +2634,7 @@ static int drbd_open(struct block_device *bdev, fmode_t mode)
 	if (!rv)
 		mdev->open_cnt++;
 	spin_unlock_irqrestore(&mdev->req_lock, flags);
+	unlock_kernel();
 
 	return rv;
 }
@@ -2640,7 +2642,9 @@ static int drbd_open(struct block_device *bdev, fmode_t mode)
 static int drbd_release(struct gendisk *gd, fmode_t mode)
 {
 	struct drbd_conf *mdev = gd->private_data;
+	lock_kernel();
 	mdev->open_cnt--;
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/block/floppy.c b/drivers/block/floppy.c
index c61df47..73f1fd9 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -3662,6 +3662,7 @@ static int floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	int drive = (long)disk->private_data;
 
+	lock_kernel();
 	mutex_lock(&open_lock);
 	if (UDRS->fd_ref < 0)
 		UDRS->fd_ref = 0;
@@ -3672,6 +3673,7 @@ static int floppy_release(struct gendisk *disk, fmode_t mode)
 	if (!UDRS->fd_ref)
 		opened_bdev[drive] = NULL;
 	mutex_unlock(&open_lock);
+	unlock_kernel();
 
 	return 0;
 }
@@ -3689,6 +3691,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	int res = -EBUSY;
 	char *tmp;
 
+	lock_kernel();
 	mutex_lock(&open_lock);
 	old_dev = UDRS->fd_device;
 	if (opened_bdev[drive] && opened_bdev[drive] != bdev)
@@ -3765,6 +3768,7 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 			goto out;
 	}
 	mutex_unlock(&open_lock);
+	unlock_kernel();
 	return 0;
 out:
 	if (UDRS->fd_ref < 0)
@@ -3775,6 +3779,7 @@ out:
 		opened_bdev[drive] = NULL;
 out2:
 	mutex_unlock(&open_lock);
+	unlock_kernel();
 	return res;
 }
 
diff --git a/drivers/block/loop.c b/drivers/block/loop.c
index 6120922..b9f5026 100644
--- a/drivers/block/loop.c
+++ b/drivers/block/loop.c
@@ -67,6 +67,7 @@
 #include <linux/compat.h>
 #include <linux/suspend.h>
 #include <linux/freezer.h>
+#include <linux/smp_lock.h>
 #include <linux/writeback.h>
 #include <linux/buffer_head.h>		/* for invalidate_bdev() */
 #include <linux/completion.h>
@@ -1408,9 +1409,11 @@ static int lo_open(struct block_device *bdev, fmode_t mode)
 {
 	struct loop_device *lo = bdev->bd_disk->private_data;
 
+	lock_kernel();
 	mutex_lock(&lo->lo_ctl_mutex);
 	lo->lo_refcnt++;
 	mutex_unlock(&lo->lo_ctl_mutex);
+	unlock_kernel();
 
 	return 0;
 }
@@ -1420,6 +1423,7 @@ static int lo_release(struct gendisk *disk, fmode_t mode)
 	struct loop_device *lo = disk->private_data;
 	int err;
 
+	lock_kernel();
 	mutex_lock(&lo->lo_ctl_mutex);
 
 	if (--lo->lo_refcnt)
@@ -1444,6 +1448,7 @@ static int lo_release(struct gendisk *disk, fmode_t mode)
 out:
 	mutex_unlock(&lo->lo_ctl_mutex);
 out_unlocked:
+	lock_kernel();
 	return 0;
 }
 
diff --git a/drivers/block/paride/pcd.c b/drivers/block/paride/pcd.c
index daba7a6..76f8565 100644
--- a/drivers/block/paride/pcd.c
+++ b/drivers/block/paride/pcd.c
@@ -225,13 +225,21 @@ static char *pcd_buf;		/* buffer for request in progress */
 static int pcd_block_open(struct block_device *bdev, fmode_t mode)
 {
 	struct pcd_unit *cd = bdev->bd_disk->private_data;
-	return cdrom_open(&cd->info, bdev, mode);
+	int ret;
+
+	lock_kernel();
+	ret = cdrom_open(&cd->info, bdev, mode);
+	unlock_kernel();
+
+	return ret;
 }
 
 static int pcd_block_release(struct gendisk *disk, fmode_t mode)
 {
 	struct pcd_unit *cd = disk->private_data;
+	lock_kernel();
 	cdrom_release(&cd->info, mode);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/block/paride/pd.c b/drivers/block/paride/pd.c
index b22943a..ad8d3a8 100644
--- a/drivers/block/paride/pd.c
+++ b/drivers/block/paride/pd.c
@@ -736,12 +736,14 @@ static int pd_open(struct block_device *bdev, fmode_t mode)
 {
 	struct pd_unit *disk = bdev->bd_disk->private_data;
 
+	lock_kernel();
 	disk->access++;
 
 	if (disk->removable) {
 		pd_special_command(disk, pd_media_check);
 		pd_special_command(disk, pd_door_lock);
 	}
+	unlock_kernel();
 	return 0;
 }
 
@@ -783,8 +785,10 @@ static int pd_release(struct gendisk *p, fmode_t mode)
 {
 	struct pd_unit *disk = p->private_data;
 
+	lock_kernel();
 	if (!--disk->access && disk->removable)
 		pd_special_command(disk, pd_door_unlock);
+	unlock_kernel();
 
 	return 0;
 }
diff --git a/drivers/block/paride/pf.c b/drivers/block/paride/pf.c
index 38b4d56..4457b49 100644
--- a/drivers/block/paride/pf.c
+++ b/drivers/block/paride/pf.c
@@ -300,20 +300,26 @@ static void __init pf_init_units(void)
 static int pf_open(struct block_device *bdev, fmode_t mode)
 {
 	struct pf_unit *pf = bdev->bd_disk->private_data;
+	int ret;
 
+	lock_kernel();
 	pf_identify(pf);
 
+	ret = -ENODEV;
 	if (pf->media_status == PF_NM)
-		return -ENODEV;
+		goto out;
 
+	ret = -EROFS;
 	if ((pf->media_status == PF_RO) && (mode & FMODE_WRITE))
-		return -EROFS;
+		goto out;
 
+	ret = 0;
 	pf->access++;
 	if (pf->removable)
 		pf_lock(pf, 1);
-
-	return 0;
+out:
+	unlock_kernel();
+	return ret;
 }
 
 static int pf_getgeo(struct block_device *bdev, struct hd_geometry *geo)
@@ -354,14 +360,18 @@ static int pf_release(struct gendisk *disk, fmode_t mode)
 {
 	struct pf_unit *pf = disk->private_data;
 
-	if (pf->access <= 0)
+	lock_kernel();
+	if (pf->access <= 0) {
+		unlock_kernel();
 		return -EINVAL;
+	}
 
 	pf->access--;
 
 	if (!pf->access && pf->removable)
 		pf_lock(pf, 0);
 
+	unlock_kernel();
 	return 0;
 
 }
diff --git a/drivers/block/pktcdvd.c b/drivers/block/pktcdvd.c
index 1f70aec..4f2e12f 100644
--- a/drivers/block/pktcdvd.c
+++ b/drivers/block/pktcdvd.c
@@ -2383,6 +2383,7 @@ static int pkt_open(struct block_device *bdev, fmode_t mode)
 
 	VPRINTK(DRIVER_NAME": entering open\n");
 
+	lock_kernel();
 	mutex_lock(&ctl_mutex);
 	pd = pkt_find_dev_from_minor(MINOR(bdev->bd_dev));
 	if (!pd) {
@@ -2410,6 +2411,7 @@ static int pkt_open(struct block_device *bdev, fmode_t mode)
 	}
 
 	mutex_unlock(&ctl_mutex);
+	unlock_kernel();
 	return 0;
 
 out_dec:
@@ -2417,6 +2419,7 @@ out_dec:
 out:
 	VPRINTK(DRIVER_NAME": failed open (%d)\n", ret);
 	mutex_unlock(&ctl_mutex);
+	unlock_kernel();
 	return ret;
 }
 
@@ -2425,6 +2428,7 @@ static int pkt_close(struct gendisk *disk, fmode_t mode)
 	struct pktcdvd_device *pd = disk->private_data;
 	int ret = 0;
 
+	lock_kernel();
 	mutex_lock(&ctl_mutex);
 	pd->refcnt--;
 	BUG_ON(pd->refcnt < 0);
@@ -2433,6 +2437,7 @@ static int pkt_close(struct gendisk *disk, fmode_t mode)
 		pkt_release_dev(pd, flush);
 	}
 	mutex_unlock(&ctl_mutex);
+	unlock_kernel();
 	return ret;
 }
 
diff --git a/drivers/block/swim.c b/drivers/block/swim.c
index f04f74e..2e46815 100644
--- a/drivers/block/swim.c
+++ b/drivers/block/swim.c
@@ -662,11 +662,23 @@ out:
 	return err;
 }
 
+static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	lock_kernel();
+	ret = floppy_open(bdev, mode);
+	unlock_kernel();
+
+	return ret;
+}
+
 static int floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	struct floppy_state *fs = disk->private_data;
 	struct swim __iomem *base = fs->swd->base;
 
+	lock_kernel();
 	if (fs->ref_count < 0)
 		fs->ref_count = 0;
 	else if (fs->ref_count > 0)
@@ -674,6 +686,7 @@ static int floppy_release(struct gendisk *disk, fmode_t mode)
 
 	if (fs->ref_count == 0)
 		swim_motor(base, OFF);
+	unlock_kernel();
 
 	return 0;
 }
@@ -754,7 +767,7 @@ static int floppy_revalidate(struct gendisk *disk)
 
 static const struct block_device_operations floppy_fops = {
 	.owner		 = THIS_MODULE,
-	.open		 = floppy_open,
+	.open		 = floppy_unlocked_open,
 	.release	 = floppy_release,
 	.ioctl		 = floppy_ioctl,
 	.getgeo		 = floppy_getgeo,
diff --git a/drivers/block/swim3.c b/drivers/block/swim3.c
index 4a83540..8f1334e 100644
--- a/drivers/block/swim3.c
+++ b/drivers/block/swim3.c
@@ -949,15 +949,28 @@ static int floppy_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
+static int floppy_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	lock_kernel();
+	ret = floppy_open(bdev, mode);
+	unlock_kernel();
+
+	return ret;
+}
+
 static int floppy_release(struct gendisk *disk, fmode_t mode)
 {
 	struct floppy_state *fs = disk->private_data;
 	struct swim3 __iomem *sw = fs->swim3;
+	lock_kernel();
 	if (fs->ref_count > 0 && --fs->ref_count == 0) {
 		swim3_action(fs, MOTOR_OFF);
 		out_8(&sw->control_bic, 0xff);
 		swim3_select(fs, RELAX);
 	}
+	unlock_kernel();
 	return 0;
 }
 
@@ -1008,7 +1021,7 @@ static int floppy_revalidate(struct gendisk *disk)
 }
 
 static const struct block_device_operations floppy_fops = {
-	.open		= floppy_open,
+	.open		= floppy_unlocked_open,
 	.release	= floppy_release,
 	.ioctl		= floppy_unlocked_ioctl,
 	.media_changed	= floppy_check_change,
diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index d6e14d2..6701886 100644
--- a/drivers/block/ub.c
+++ b/drivers/block/ub.c
@@ -1711,6 +1711,18 @@ err_open:
 	return rc;
 }
 
+static int ub_bd_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	lock_kernel();
+	ret = ub_bd_open(bdev, mode);
+	unlock_kernel();
+
+	return ret;
+}
+
+
 /*
  */
 static int ub_bd_release(struct gendisk *disk, fmode_t mode)
@@ -1718,7 +1730,10 @@ static int ub_bd_release(struct gendisk *disk, fmode_t mode)
 	struct ub_lun *lun = disk->private_data;
 	struct ub_dev *sc = lun->udev;
 
+	lock_kernel();
 	ub_put(sc);
+	unlock_kernel();
+
 	return 0;
 }
 
@@ -1798,7 +1813,7 @@ static int ub_bd_media_changed(struct gendisk *disk)
 
 static const struct block_device_operations ub_bd_fops = {
 	.owner		= THIS_MODULE,
-	.open		= ub_bd_open,
+	.open		= ub_bd_unlocked_open,
 	.release	= ub_bd_release,
 	.ioctl		= ub_bd_ioctl,
 	.media_changed	= ub_bd_media_changed,
diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c
index 788d938..3cbc85c 100644
--- a/drivers/block/viodasd.c
+++ b/drivers/block/viodasd.c
@@ -41,6 +41,7 @@
 #include <linux/errno.h>
 #include <linux/init.h>
 #include <linux/string.h>
+#include <linux/smp_lock.h>
 #include <linux/dma-mapping.h>
 #include <linux/completion.h>
 #include <linux/device.h>
@@ -175,6 +176,18 @@ static int viodasd_open(struct block_device *bdev, fmode_t mode)
 	return 0;
 }
 
+static int viodasd_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	lock_kernel();
+	ret = viodasd_open(bdev, mode);
+	unlock_kernel();
+
+	return ret;
+}
+
+
 /*
  * External release entry point.
  */
@@ -183,6 +196,7 @@ static int viodasd_release(struct gendisk *disk, fmode_t mode)
 	struct viodasd_device *d = disk->private_data;
 	HvLpEvent_Rc hvrc;
 
+	lock_kernel();
 	/* Send the event to OS/400.  We DON'T expect a response */
 	hvrc = HvCallEvent_signalLpEventFast(viopath_hostLp,
 			HvLpEvent_Type_VirtualIo,
@@ -195,6 +209,9 @@ static int viodasd_release(struct gendisk *disk, fmode_t mode)
 			0, 0, 0);
 	if (hvrc != 0)
 		pr_warning("HV close call failed %d\n", (int)hvrc);
+
+	unlock_kernel();
+
 	return 0;
 }
 
@@ -219,7 +236,7 @@ static int viodasd_getgeo(struct block_device *bdev, struct hd_geometry *geo)
  */
 static const struct block_device_operations viodasd_fops = {
 	.owner = THIS_MODULE,
-	.open = viodasd_open,
+	.open = viodasd_unlocked_open,
 	.release = viodasd_release,
 	.getgeo = viodasd_getgeo,
 };
diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 96a70bb..dfb3dce 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -41,6 +41,7 @@
 #include <linux/cdrom.h>
 #include <linux/module.h>
 #include <linux/slab.h>
+#include <linux/smp_lock.h>
 #include <linux/scatterlist.h>
 
 #include <xen/xen.h>
@@ -1019,13 +1020,18 @@ static int blkfront_is_ready(struct xenbus_device *dev)
 static int blkif_open(struct block_device *bdev, fmode_t mode)
 {
 	struct blkfront_info *info = bdev->bd_disk->private_data;
+
+	lock_kernel();
 	info->users++;
+	unlock_kernel();
+
 	return 0;
 }
 
 static int blkif_release(struct gendisk *disk, fmode_t mode)
 {
 	struct blkfront_info *info = disk->private_data;
+	lock_kernel();
 	info->users--;
 	if (info->users == 0) {
 		/* Check whether we have been instructed to close.  We will
@@ -1037,6 +1043,7 @@ static int blkif_release(struct gendisk *disk, fmode_t mode)
 		if (state == XenbusStateClosing && info->is_ready)
 			blkfront_closing(dev);
 	}
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/block/xsysace.c b/drivers/block/xsysace.c
index a7b83c0..8d435c9 100644
--- a/drivers/block/xsysace.c
+++ b/drivers/block/xsysace.c
@@ -89,6 +89,7 @@
 #include <linux/delay.h>
 #include <linux/slab.h>
 #include <linux/blkdev.h>
+#include <linux/smp_lock.h>
 #include <linux/ata.h>
 #include <linux/hdreg.h>
 #include <linux/platform_device.h>
@@ -901,11 +902,14 @@ static int ace_open(struct block_device *bdev, fmode_t mode)
 
 	dev_dbg(ace->dev, "ace_open() users=%i\n", ace->users + 1);
 
+	lock_kernel();
 	spin_lock_irqsave(&ace->lock, flags);
 	ace->users++;
 	spin_unlock_irqrestore(&ace->lock, flags);
 
 	check_disk_change(bdev);
+	unlock_kernel();
+
 	return 0;
 }
 
@@ -917,6 +921,7 @@ static int ace_release(struct gendisk *disk, fmode_t mode)
 
 	dev_dbg(ace->dev, "ace_release() users=%i\n", ace->users - 1);
 
+	lock_kernel();
 	spin_lock_irqsave(&ace->lock, flags);
 	ace->users--;
 	if (ace->users == 0) {
@@ -924,6 +929,7 @@ static int ace_release(struct gendisk *disk, fmode_t mode)
 		ace_out(ace, ACE_CTRL, val & ~ACE_CTRL_LOCKREQ);
 	}
 	spin_unlock_irqrestore(&ace->lock, flags);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/block/z2ram.c b/drivers/block/z2ram.c
index 9114654..d75b2bb 100644
--- a/drivers/block/z2ram.c
+++ b/drivers/block/z2ram.c
@@ -33,6 +33,7 @@
 #include <linux/module.h>
 #include <linux/blkdev.h>
 #include <linux/bitops.h>
+#include <linux/smp_lock.h>
 #include <linux/slab.h>
 
 #include <asm/setup.h>
@@ -153,6 +154,7 @@ static int z2_open(struct block_device *bdev, fmode_t mode)
 
     device = MINOR(bdev->bd_dev);
 
+    lock_kernel();
     if ( current_device != -1 && current_device != device )
     {
 	rc = -EBUSY;
@@ -294,20 +296,25 @@ static int z2_open(struct block_device *bdev, fmode_t mode)
 	set_capacity(z2ram_gendisk, z2ram_size >> 9);
     }
 
+    unlock_kernel();
     return 0;
 
 err_out_kfree:
     kfree(z2ram_map);
 err_out:
+    unlock_kernel();
     return rc;
 }
 
 static int
 z2_release(struct gendisk *disk, fmode_t mode)
 {
-    if ( current_device == -1 )
-	return 0;     
-
+    lock_kernel();
+    if ( current_device == -1 ) {
+    	unlock_kernel();
+    	return 0;
+    }
+    unlock_kernel();
     /*
      * FIXME: unmap memory
      */
diff --git a/drivers/cdrom/gdrom.c b/drivers/cdrom/gdrom.c
index 7d7b894..b5bacd1 100644
--- a/drivers/cdrom/gdrom.c
+++ b/drivers/cdrom/gdrom.c
@@ -493,12 +493,18 @@ static struct cdrom_device_ops gdrom_ops = {
 
 static int gdrom_bdops_open(struct block_device *bdev, fmode_t mode)
 {
-	return cdrom_open(gd.cd_info, bdev, mode);
+	int ret;
+	lock_kernel();
+	ret = cdrom_open(gd.cd_info, bdev, mode);
+	unlock_kernel();
+	return ret;
 }
 
 static int gdrom_bdops_release(struct gendisk *disk, fmode_t mode)
 {
+	lock_kernel();
 	cdrom_release(gd.cd_info, mode);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/cdrom/viocd.c b/drivers/cdrom/viocd.c
index 203c87c..74d7e55 100644
--- a/drivers/cdrom/viocd.c
+++ b/drivers/cdrom/viocd.c
@@ -155,13 +155,21 @@ static const struct file_operations proc_viocd_operations = {
 static int viocd_blk_open(struct block_device *bdev, fmode_t mode)
 {
 	struct disk_info *di = bdev->bd_disk->private_data;
-	return cdrom_open(&di->viocd_info, bdev, mode);
+	int ret;
+
+	lock_kernel();
+	ret = cdrom_open(&di->viocd_info, bdev, mode);
+	unlock_kernel();
+
+	return ret;
 }
 
 static int viocd_blk_release(struct gendisk *disk, fmode_t mode)
 {
 	struct disk_info *di = disk->private_data;
+	lock_kernel();
 	cdrom_release(&di->viocd_info, mode);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/ide/ide-cd.c b/drivers/ide/ide-cd.c
index 03c93ae..a7fb6ea 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -1585,17 +1585,19 @@ static struct ide_driver ide_cdrom_driver = {
 
 static int idecd_open(struct block_device *bdev, fmode_t mode)
 {
-	struct cdrom_info *info = ide_cd_get(bdev->bd_disk);
-	int rc = -ENOMEM;
+	struct cdrom_info *info;
+	int rc = -ENXIO;
 
+	lock_kernel();
+	info = ide_cd_get(bdev->bd_disk);
 	if (!info)
-		return -ENXIO;
+		goto out;
 
 	rc = cdrom_open(&info->devinfo, bdev, mode);
-
 	if (rc < 0)
 		ide_cd_put(info);
-
+out:
+	unlock_kernel();
 	return rc;
 }
 
@@ -1603,9 +1605,11 @@ static int idecd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct cdrom_info *info = ide_drv_g(disk, cdrom_info);
 
+	lock_kernel();
 	cdrom_release(&info->devinfo, mode);
 
 	ide_cd_put(info);
+	unlock_kernel();
 
 	return 0;
 }
diff --git a/drivers/ide/ide-gd.c b/drivers/ide/ide-gd.c
index 883f0c9..137337a 100644
--- a/drivers/ide/ide-gd.c
+++ b/drivers/ide/ide-gd.c
@@ -1,3 +1,4 @@
+#include <linux/smp_lock.h>
 #include <linux/module.h>
 #include <linux/types.h>
 #include <linux/string.h>
@@ -237,6 +238,18 @@ out_put_idkp:
 	return ret;
 }
 
+static int ide_gd_unlocked_open(struct block_device *bdev, fmode_t mode)
+{
+	int ret;
+
+	lock_kernel();
+	ret = ide_gd_open(bdev, mode);
+	unlock_kernel();
+
+	return ret;
+}
+
+
 static int ide_gd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct ide_disk_obj *idkp = ide_drv_g(disk, ide_disk_obj);
@@ -244,6 +257,7 @@ static int ide_gd_release(struct gendisk *disk, fmode_t mode)
 
 	ide_debug_log(IDE_DBG_FUNC, "enter");
 
+	lock_kernel();
 	if (idkp->openers == 1)
 		drive->disk_ops->flush(drive);
 
@@ -255,6 +269,7 @@ static int ide_gd_release(struct gendisk *disk, fmode_t mode)
 	idkp->openers--;
 
 	ide_disk_put(idkp);
+	unlock_kernel();
 
 	return 0;
 }
@@ -321,7 +336,7 @@ static int ide_gd_ioctl(struct block_device *bdev, fmode_t mode,
 
 static const struct block_device_operations ide_gd_ops = {
 	.owner			= THIS_MODULE,
-	.open			= ide_gd_open,
+	.open			= ide_gd_unlocked_open,
 	.release		= ide_gd_release,
 	.ioctl			= ide_gd_ioctl,
 	.getgeo			= ide_gd_getgeo,
diff --git a/drivers/ide/ide-tape.c b/drivers/ide/ide-tape.c
index 2487916..c50061e 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -1906,7 +1906,11 @@ static const struct file_operations idetape_fops = {
 
 static int idetape_open(struct block_device *bdev, fmode_t mode)
 {
-	struct ide_tape_obj *tape = ide_tape_get(bdev->bd_disk, false, 0);
+	struct ide_tape_obj *tape;
+
+	lock_kernel();
+	tape = ide_tape_get(bdev->bd_disk, false, 0);
+	unlock_kernel();
 
 	if (!tape)
 		return -ENXIO;
@@ -1918,7 +1922,10 @@ static int idetape_release(struct gendisk *disk, fmode_t mode)
 {
 	struct ide_tape_obj *tape = ide_drv_g(disk, ide_tape_obj);
 
+	lock_kernel();
 	ide_tape_put(tape);
+	unlock_kernel();
+
 	return 0;
 }
 
diff --git a/drivers/md/dm.c b/drivers/md/dm.c
index d21e128..40951a2 100644
--- a/drivers/md/dm.c
+++ b/drivers/md/dm.c
@@ -15,6 +15,7 @@
 #include <linux/blkpg.h>
 #include <linux/bio.h>
 #include <linux/buffer_head.h>
+#include <linux/smp_lock.h>
 #include <linux/mempool.h>
 #include <linux/slab.h>
 #include <linux/idr.h>
@@ -338,6 +339,7 @@ static int dm_blk_open(struct block_device *bdev, fmode_t mode)
 {
 	struct mapped_device *md;
 
+	lock_kernel();
 	spin_lock(&_minor_lock);
 
 	md = bdev->bd_disk->private_data;
@@ -355,6 +357,7 @@ static int dm_blk_open(struct block_device *bdev, fmode_t mode)
 
 out:
 	spin_unlock(&_minor_lock);
+	unlock_kernel();
 
 	return md ? 0 : -ENXIO;
 }
@@ -362,8 +365,12 @@ out:
 static int dm_blk_close(struct gendisk *disk, fmode_t mode)
 {
 	struct mapped_device *md = disk->private_data;
+
+	lock_kernel();
 	atomic_dec(&md->open_count);
 	dm_put(md);
+	unlock_kernel();
+
 	return 0;
 }
 
diff --git a/drivers/md/md.c b/drivers/md/md.c
index 46b3a04..3e8ae77 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -36,6 +36,7 @@
 #include <linux/blkdev.h>
 #include <linux/sysctl.h>
 #include <linux/seq_file.h>
+#include <linux/smp_lock.h>
 #include <linux/buffer_head.h> /* for invalidate_bdev */
 #include <linux/poll.h>
 #include <linux/ctype.h>
@@ -5876,6 +5877,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
 	mddev_t *mddev = mddev_find(bdev->bd_dev);
 	int err;
 
+	lock_kernel();
 	if (mddev->gendisk != bdev->bd_disk) {
 		/* we are racing with mddev_put which is discarding this
 		 * bd_disk.
@@ -5884,6 +5886,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
 		/* Wait until bdev->bd_disk is definitely gone */
 		flush_scheduled_work();
 		/* Then retry the open from the top */
+		unlock_kernel();
 		return -ERESTARTSYS;
 	}
 	BUG_ON(mddev != bdev->bd_disk->private_data);
@@ -5896,6 +5899,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
 	mutex_unlock(&mddev->open_mutex);
 
  out:
+	unlock_kernel();
 	return err;
 }
 
@@ -5904,8 +5908,10 @@ static int md_release(struct gendisk *disk, fmode_t mode)
  	mddev_t *mddev = disk->private_data;
 
 	BUG_ON(!mddev);
+	lock_kernel();
 	atomic_dec(&mddev->openers);
 	mddev_put(mddev);
+	unlock_kernel();
 
 	return 0;
 }
diff --git a/drivers/memstick/core/mspro_block.c b/drivers/memstick/core/mspro_block.c
index 8327e24..5b1c2cf 100644
--- a/drivers/memstick/core/mspro_block.c
+++ b/drivers/memstick/core/mspro_block.c
@@ -18,6 +18,7 @@
 #include <linux/kthread.h>
 #include <linux/delay.h>
 #include <linux/slab.h>
+#include <linux/smp_lock.h>
 #include <linux/memstick.h>
 
 #define DRIVER_NAME "mspro_block"
@@ -179,6 +180,7 @@ static int mspro_block_bd_open(struct block_device *bdev, fmode_t mode)
 	struct mspro_block_data *msb = disk->private_data;
 	int rc = -ENXIO;
 
+	lock_kernel();
 	mutex_lock(&mspro_block_disk_lock);
 
 	if (msb && msb->card) {
@@ -190,6 +192,7 @@ static int mspro_block_bd_open(struct block_device *bdev, fmode_t mode)
 	}
 
 	mutex_unlock(&mspro_block_disk_lock);
+	unlock_kernel();
 
 	return rc;
 }
@@ -221,7 +224,11 @@ static int mspro_block_disk_release(struct gendisk *disk)
 
 static int mspro_block_bd_release(struct gendisk *disk, fmode_t mode)
 {
-	return mspro_block_disk_release(disk);
+	int ret;
+	lock_kernel();
+	ret = mspro_block_disk_release(disk);
+	unlock_kernel();
+	return ret;
 }
 
 static int mspro_block_bd_getgeo(struct block_device *bdev,
diff --git a/drivers/message/i2o/i2o_block.c b/drivers/message/i2o/i2o_block.c
index 1f3b080..5a9e477 100644
--- a/drivers/message/i2o/i2o_block.c
+++ b/drivers/message/i2o/i2o_block.c
@@ -578,6 +578,7 @@ static int i2o_block_open(struct block_device *bdev, fmode_t mode)
 	if (!dev->i2o_dev)
 		return -ENODEV;
 
+	lock_kernel();
 	if (dev->power > 0x1f)
 		i2o_block_device_power(dev, 0x02);
 
@@ -586,6 +587,7 @@ static int i2o_block_open(struct block_device *bdev, fmode_t mode)
 	i2o_block_device_lock(dev->i2o_dev, -1);
 
 	osm_debug("Ready.\n");
+	unlock_kernel();
 
 	return 0;
 };
@@ -616,6 +618,7 @@ static int i2o_block_release(struct gendisk *disk, fmode_t mode)
 	if (!dev->i2o_dev)
 		return 0;
 
+	lock_kernel();
 	i2o_block_device_flush(dev->i2o_dev);
 
 	i2o_block_device_unlock(dev->i2o_dev, -1);
@@ -626,6 +629,7 @@ static int i2o_block_release(struct gendisk *disk, fmode_t mode)
 		operation = 0x24;
 
 	i2o_block_device_power(dev, operation);
+	unlock_kernel();
 
 	return 0;
 }
diff --git a/drivers/mmc/card/block.c b/drivers/mmc/card/block.c
index cb9fbc8..8433cde 100644
--- a/drivers/mmc/card/block.c
+++ b/drivers/mmc/card/block.c
@@ -29,6 +29,7 @@
 #include <linux/kdev_t.h>
 #include <linux/blkdev.h>
 #include <linux/mutex.h>
+#include <linux/smp_lock.h>
 #include <linux/scatterlist.h>
 #include <linux/string_helpers.h>
 
@@ -107,6 +108,7 @@ static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
 	struct mmc_blk_data *md = mmc_blk_get(bdev->bd_disk);
 	int ret = -ENXIO;
 
+	lock_kernel();
 	if (md) {
 		if (md->usage == 2)
 			check_disk_change(bdev);
@@ -117,6 +119,7 @@ static int mmc_blk_open(struct block_device *bdev, fmode_t mode)
 			ret = -EROFS;
 		}
 	}
+	unlock_kernel();
 
 	return ret;
 }
@@ -125,7 +128,9 @@ static int mmc_blk_release(struct gendisk *disk, fmode_t mode)
 {
 	struct mmc_blk_data *md = disk->private_data;
 
+	lock_kernel();
 	mmc_blk_put(md);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/mtd/mtd_blkdevs.c b/drivers/mtd/mtd_blkdevs.c
index 3ddc95b..7133918 100644
--- a/drivers/mtd/mtd_blkdevs.c
+++ b/drivers/mtd/mtd_blkdevs.c
@@ -165,8 +165,9 @@ static int blktrans_open(struct block_device *bdev, fmode_t mode)
 	int ret;
 
 	if (!dev)
-		return -ERESTARTSYS;
+		return -ERESTARTSYS; /* FIXME: busy loop! -arnd*/
 
+	lock_kernel();
 	mutex_lock(&dev->lock);
 
 	if (!dev->mtd) {
@@ -183,6 +184,7 @@ static int blktrans_open(struct block_device *bdev, fmode_t mode)
 unlock:
 	mutex_unlock(&dev->lock);
 	blktrans_dev_put(dev);
+	unlock_kernel();
 	return ret;
 }
 
@@ -194,6 +196,7 @@ static int blktrans_release(struct gendisk *disk, fmode_t mode)
 	if (!dev)
 		return ret;
 
+	lock_kernel();
 	mutex_lock(&dev->lock);
 
 	/* Release one reference, we sure its not the last one here*/
@@ -206,6 +209,7 @@ static int blktrans_release(struct gendisk *disk, fmode_t mode)
 unlock:
 	mutex_unlock(&dev->lock);
 	blktrans_dev_put(dev);
+	unlock_kernel();
 	return ret;
 }
 
diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 33975e9..ae9da0d 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -21,6 +21,7 @@
 #include <linux/hdreg.h>
 #include <linux/async.h>
 #include <linux/mutex.h>
+#include <linux/smp_lock.h>
 
 #include <asm/ccwdev.h>
 #include <asm/ebcdic.h>
@@ -2235,6 +2236,7 @@ static int dasd_open(struct block_device *bdev, fmode_t mode)
 	if (!block)
 		return -ENODEV;
 
+	lock_kernel();
 	base = block->base;
 	atomic_inc(&block->open_count);
 	if (test_bit(DASD_FLAG_OFFLINE, &base->flags)) {
@@ -2269,12 +2271,14 @@ static int dasd_open(struct block_device *bdev, fmode_t mode)
 		goto out;
 	}
 
+	unlock_kernel();
 	return 0;
 
 out:
 	module_put(base->discipline->owner);
 unlock:
 	atomic_dec(&block->open_count);
+	unlock_kernel();
 	return rc;
 }
 
@@ -2282,8 +2286,10 @@ static int dasd_release(struct gendisk *disk, fmode_t mode)
 {
 	struct dasd_block *block = disk->private_data;
 
+	lock_kernel();
 	atomic_dec(&block->open_count);
 	module_put(block->base->discipline->owner);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/s390/block/dcssblk.c b/drivers/s390/block/dcssblk.c
index 9b43ae9..2bd72aa 100644
--- a/drivers/s390/block/dcssblk.c
+++ b/drivers/s390/block/dcssblk.c
@@ -14,6 +14,7 @@
 #include <linux/init.h>
 #include <linux/slab.h>
 #include <linux/blkdev.h>
+#include <linux/smp_lock.h>
 #include <linux/completion.h>
 #include <linux/interrupt.h>
 #include <linux/platform_device.h>
@@ -775,6 +776,7 @@ dcssblk_open(struct block_device *bdev, fmode_t mode)
 	struct dcssblk_dev_info *dev_info;
 	int rc;
 
+	lock_kernel();
 	dev_info = bdev->bd_disk->private_data;
 	if (NULL == dev_info) {
 		rc = -ENODEV;
@@ -784,6 +786,7 @@ dcssblk_open(struct block_device *bdev, fmode_t mode)
 	bdev->bd_block_size = 4096;
 	rc = 0;
 out:
+	unlock_kernel();
 	return rc;
 }
 
@@ -794,6 +797,7 @@ dcssblk_release(struct gendisk *disk, fmode_t mode)
 	struct segment_info *entry;
 	int rc;
 
+	lock_kernel();
 	if (!dev_info) {
 		rc = -ENODEV;
 		goto out;
@@ -811,6 +815,7 @@ dcssblk_release(struct gendisk *disk, fmode_t mode)
 	up_write(&dcssblk_devices_sem);
 	rc = 0;
 out:
+	unlock_kernel();
 	return rc;
 }
 
diff --git a/drivers/s390/char/tape_block.c b/drivers/s390/char/tape_block.c
index 097da8c..b7de025 100644
--- a/drivers/s390/char/tape_block.c
+++ b/drivers/s390/char/tape_block.c
@@ -16,6 +16,7 @@
 #include <linux/fs.h>
 #include <linux/module.h>
 #include <linux/blkdev.h>
+#include <linux/smp_lock.h>
 #include <linux/interrupt.h>
 #include <linux/buffer_head.h>
 #include <linux/kernel.h>
@@ -361,6 +362,7 @@ tapeblock_open(struct block_device *bdev, fmode_t mode)
 	struct tape_device *	device;
 	int			rc;
 
+	lock_kernel();
 	device = tape_get_device(disk->private_data);
 
 	if (device->required_tapemarks) {
@@ -384,12 +386,14 @@ tapeblock_open(struct block_device *bdev, fmode_t mode)
 	 *       is called.
 	 */
 	tape_state_set(device, TS_BLKUSE);
+	unlock_kernel();
 	return 0;
 
 release:
 	tape_release(device);
  put_device:
 	tape_put_device(device);
+	unlock_kernel();
 	return rc;
 }
 
@@ -403,10 +407,12 @@ static int
 tapeblock_release(struct gendisk *disk, fmode_t mode)
 {
 	struct tape_device *device = disk->private_data;
-
+ 
+	lock_kernel();
 	tape_state_set(device, TS_IN_USE);
 	tape_release(device);
 	tape_put_device(device);
+	unlock_kernel();
 
 	return 0;
 }
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 858c89d..01fbfe1 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -757,6 +757,7 @@ static int sd_open(struct block_device *bdev, fmode_t mode)
 
 	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_open\n"));
 
+	lock_kernel();
 	sdev = sdkp->device;
 
 	/*
@@ -800,10 +801,12 @@ static int sd_open(struct block_device *bdev, fmode_t mode)
 			scsi_set_medium_removal(sdev, SCSI_REMOVAL_PREVENT);
 	}
 
+	unlock_kernel();
 	return 0;
 
 error_out:
 	scsi_disk_put(sdkp);
+	unlock_kernel();
 	return retval;	
 }
 
@@ -825,6 +828,7 @@ static int sd_release(struct gendisk *disk, fmode_t mode)
 
 	SCSI_LOG_HLQUEUE(3, sd_printk(KERN_INFO, sdkp, "sd_release\n"));
 
+	lock_kernel();
 	if (!--sdkp->openers && sdev->removable) {
 		if (scsi_block_when_processing_errors(sdev))
 			scsi_set_medium_removal(sdev, SCSI_REMOVAL_ALLOW);
@@ -835,6 +839,7 @@ static int sd_release(struct gendisk *disk, fmode_t mode)
 	 * XXX is followed by a "rmmod sd_mod"?
 	 */
 	scsi_disk_put(sdkp);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index ad62aa8..906f8e7 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -467,22 +467,27 @@ static int sr_prep_fn(struct request_queue *q, struct request *rq)
 
 static int sr_block_open(struct block_device *bdev, fmode_t mode)
 {
-	struct scsi_cd *cd = scsi_cd_get(bdev->bd_disk);
+	struct scsi_cd *cd;
 	int ret = -ENXIO;
 
+	lock_kernel();
+	cd = scsi_cd_get(bdev->bd_disk);
 	if (cd) {
 		ret = cdrom_open(&cd->cdi, bdev, mode);
 		if (ret)
 			scsi_cd_put(cd);
 	}
+	unlock_kernel();
 	return ret;
 }
 
 static int sr_block_release(struct gendisk *disk, fmode_t mode)
 {
 	struct scsi_cd *cd = scsi_cd(disk);
+	lock_kernel();
 	cdrom_release(&cd->cdi, mode);
 	scsi_cd_put(cd);
+	unlock_kernel();
 	return 0;
 }
 
diff --git a/drivers/staging/hv/blkvsc_drv.c b/drivers/staging/hv/blkvsc_drv.c
index 61bd0be..d3947ca 100644
--- a/drivers/staging/hv/blkvsc_drv.c
+++ b/drivers/staging/hv/blkvsc_drv.c
@@ -25,6 +25,7 @@
 #include <linux/major.h>
 #include <linux/delay.h>
 #include <linux/hdreg.h>
+#include <linux/smp_lock.h>
 #include <linux/slab.h>
 #include <scsi/scsi.h>
 #include <scsi/scsi_cmnd.h>
@@ -1324,6 +1325,7 @@ static int blkvsc_open(struct block_device *bdev, fmode_t mode)
 	DPRINT_DBG(BLKVSC_DRV, "- users %d disk %s\n", blkdev->users,
 		   blkdev->gd->disk_name);
 
+	lock_kernel();
 	spin_lock(&blkdev->lock);
 
 	if (!blkdev->users && blkdev->device_type == DVD_TYPE) {
@@ -1335,6 +1337,7 @@ static int blkvsc_open(struct block_device *bdev, fmode_t mode)
 	blkdev->users++;
 
 	spin_unlock(&blkdev->lock);
+	unlock_kernel();
 	return 0;
 }
 
@@ -1345,6 +1348,7 @@ static int blkvsc_release(struct gendisk *disk, fmode_t mode)
 	DPRINT_DBG(BLKVSC_DRV, "- users %d disk %s\n", blkdev->users,
 		   blkdev->gd->disk_name);
 
+	lock_kernel();
 	spin_lock(&blkdev->lock);
 	if (blkdev->users == 1) {
 		spin_unlock(&blkdev->lock);
@@ -1355,6 +1359,7 @@ static int blkvsc_release(struct gendisk *disk, fmode_t mode)
 	blkdev->users--;
 
 	spin_unlock(&blkdev->lock);
+	unlock_kernel();
 	return 0;
 }
 

^ permalink raw reply related	[flat|nested] 5+ messages in thread

end of thread, other threads:[~2010-06-02 14:46 UTC | newest]

Thread overview: 5+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2010-06-01 21:33 [PATCH] block: replace BKL with global mutex Arnd Bergmann
2010-06-01 21:37 ` Christoph Hellwig
2010-06-01 22:43   ` [PATCH] block: push down BKL into .locked_ioctl Arnd Bergmann
2010-06-02 10:16     ` Christoph Hellwig
2010-06-02 14:46       ` [PATCH] block: push down BKL into .open and .release Arnd Bergmann

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).