39 files changed, 334 insertions, 48 deletions

diff --git a/arch/um/drivers/ubd_kern.c b/arch/um/drivers/ubd_kern.c
index da992a3ad6b7..1bcd208c459f 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 c5f22bb0a48e..4e2c367fec11 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 0fa26359304c..76f114f0bba3 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 65deffde60ac..a946929735a5 100644
--- a/drivers/block/aoe/aoeblk.c
+++ b/drivers/block/aoe/aoeblk.c
@@ -12,6 +12,7 @@
 #include <linux/slab.h>
 #include <linux/genhd.h>
 #include <linux/netdevice.h>
+#include <linux/smp_lock.h>
 #include "aoe.h"
 
 static struct kmem_cache *buf_pool_cache;
@@ -124,13 +125,16 @@ 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 1bb8bfcfdbd9..aceb96476524 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_ioctl,
         .media_changed  = check_floppy_change,
diff --git a/drivers/block/cciss.c b/drivers/block/cciss.c
index a6c0494dd054..665a470310a9 100644
--- a/drivers/block/cciss.c
+++ b/drivers/block/cciss.c
@@ -178,6 +178,7 @@ static void do_cciss_request(struct request_queue *q);
 static irqreturn_t do_cciss_intx(int irq, void *dev_id);
 static irqreturn_t do_cciss_msix_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);
@@ -237,7 +238,7 @@ 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,
@@ -1042,13 +1043,28 @@ 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);
@@ -1056,6 +1072,7 @@ 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 c459aeea3c0c..28937b661564 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_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_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 e2ab13d99d69..d2b6764a7b1f 100644
--- a/drivers/block/drbd/drbd_main.c
+++ b/drivers/block/drbd/drbd_main.c
@@ -2604,6 +2604,7 @@ 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 */
@@ -2618,6 +2619,7 @@ 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;
 }
@@ -2625,7 +2627,9 @@ 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 40419b066aa9..3126d5122b2b 100644
--- a/drivers/block/floppy.c
+++ b/drivers/block/floppy.c
@@ -3616,6 +3616,7 @@ 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;
@@ -3626,6 +3627,7 @@ 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;
 }
@@ -3643,6 +3645,7 @@ 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)
@@ -3719,6 +3722,7 @@ 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)
@@ -3729,6 +3733,7 @@ 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 d285a5481965..f3c636d23718 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 daba7a62a663..76f8565e1e8d 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 c4d6ed9846ca..985f0d4f1d1e 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 38b4d566b816..4457b494882a 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 40f1e31f42c4..b1cbeb59bb76 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 f04f74e3758f..2e46815876df 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 f3657b2a5386..cc6a3864822c 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_ioctl,
         .media_changed  = floppy_check_change,
diff --git a/drivers/block/ub.c b/drivers/block/ub.c
index 102ed52d0e0f..c48e14878582 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 5663d3c284c8..f651e51a3319 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 9119cd3d56a4..91374282755d 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>
@@ -1018,13 +1019,18 @@ 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
@@ -1036,6 +1042,7 @@ 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 ac278ac908d5..b71888b909a0 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 9114654b54d9..d75b2bb601ad 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 1772fd914fb9..261107d1457c 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 16dada0627ee..56bf9f44700c 100644
--- a/drivers/cdrom/viocd.c
+++ b/drivers/cdrom/viocd.c
@@ -154,13 +154,21 @@ 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 bf9f61a5c2f8..5108e9739c96 100644
--- a/drivers/ide/ide-cd.c
+++ b/drivers/ide/ide-cd.c
@@ -1591,17 +1591,19 @@ 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;
 }
 
@@ -1609,9 +1611,11 @@ 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 883f0c979c9f..137337a795a9 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 39b0a5c45f07..6d622cb5ac81 100644
--- a/drivers/ide/ide-tape.c
+++ b/drivers/ide/ide-tape.c
@@ -1907,7 +1907,11 @@ 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;
@@ -1919,7 +1923,10 @@ 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 d505a96845c1..a3f21dc02bd8 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 1893af678779..700c96edf9b2 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>
@@ -5902,6 +5903,7 @@ 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.
@@ -5910,6 +5912,7 @@ 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);
@@ -5923,6 +5926,7 @@ static int md_open(struct block_device *bdev, fmode_t mode)
 
         check_disk_size_change(mddev->gendisk, bdev);
  out:
+        unlock_kernel();
         return err;
 }
 
@@ -5931,8 +5935,10 @@ 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 56645408d225..eef78a068fd1 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 d1bdf8abe5db..a5bc3ee0d93e 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>
 
@@ -577,6 +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);
 
@@ -585,6 +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;
 };
@@ -615,6 +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);
@@ -625,6 +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 cb9fbc83b090..8433cde29c8b 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 8c83b11a77d5..5ca80aee2ed0 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 17b033d0e050..1a84fae155e1 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 9b43ae94beba..2bd72aa34c59 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 097da8ce6be6..b7de02525ec9 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 633ac32b25c1..01680c7c8507 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -795,6 +795,7 @@ 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;
 
         /*
@@ -838,10 +839,12 @@ 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;  
 }
 
@@ -863,6 +866,7 @@ 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);
@@ -873,6 +877,7 @@ 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 d42fa6468f41..ba9c3e0387ce 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 a9aff90e58e0..87a11c9293e9 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>
@@ -1326,6 +1327,7 @@ 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) {
@@ -1337,6 +1339,7 @@ static int blkvsc_open(struct block_device *bdev, fmode_t mode)
         blkdev->users++;
 
         spin_unlock(&blkdev->lock);
+        unlock_kernel();
         return 0;
 }
 
@@ -1347,6 +1350,7 @@ 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);
@@ -1357,6 +1361,7 @@ static int blkvsc_release(struct gendisk *disk, fmode_t mode)
         blkdev->users--;
 
         spin_unlock(&blkdev->lock);
+        unlock_kernel();
         return 0;
 }
 
diff --git a/fs/block_dev.c b/fs/block_dev.c
index 99d6af811747..693c2bf5d65e 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1345,13 +1345,12 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                 return ret;
         }
 
-        lock_kernel();
  restart:
 
         ret = -ENXIO;
         disk = get_gendisk(bdev->bd_dev, &partno);
         if (!disk)
-                goto out_unlock_kernel;
+                goto out;
 
         mutex_lock_nested(&bdev->bd_mutex, for_part);
         if (!bdev->bd_openers) {
@@ -1431,7 +1430,6 @@ 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:
@@ -1444,9 +1442,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
         bdev->bd_contains = NULL;
  out_unlock_bdev:
         mutex_unlock(&bdev->bd_mutex);
- out_unlock_kernel:
-        unlock_kernel();
-
+ out:
         if (disk)
                 module_put(disk->fops->owner);
         put_disk(disk);
@@ -1515,7 +1511,6 @@ 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--;
 
@@ -1540,7 +1535,6 @@ 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)