1 files changed, 20 insertions, 21 deletions

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index 98cbeba8cd53..4e86393a09cf 100644
--- a/drivers/block/xen-blkfront.c
+++ b/drivers/block/xen-blkfront.c
@@ -43,6 +43,7 @@
 #include <linux/slab.h>
 #include <linux/mutex.h>
 #include <linux/scatterlist.h>
+#include <linux/bitmap.h>
 
 #include <xen/xen.h>
 #include <xen/xenbus.h>
@@ -81,6 +82,7 @@ static const struct block_device_operations xlvbd_block_fops;
  */
 struct blkfront_info
 {
+        spinlock_t io_lock;
         struct mutex mutex;
         struct xenbus_device *xbdev;
         struct gendisk *gd;
@@ -105,8 +107,6 @@ struct blkfront_info
         int is_ready;
 };
 
-static DEFINE_SPINLOCK(blkif_io_lock);
-
 static unsigned int nr_minors;
 static unsigned long *minors;
 static DEFINE_SPINLOCK(minor_lock);
@@ -177,8 +177,7 @@ static int xlbd_reserve_minors(unsigned int minor, unsigned int nr)
 
         spin_lock(&minor_lock);
         if (find_next_bit(minors, end, minor) >= end) {
-                for (; minor < end; ++minor)
-                        __set_bit(minor, minors);
+                bitmap_set(minors, minor, nr);
                 rc = 0;
         } else
                 rc = -EBUSY;
@@ -193,8 +192,7 @@ static void xlbd_release_minors(unsigned int minor, unsigned int nr)
 
         BUG_ON(end > nr_minors);
         spin_lock(&minor_lock);
-        for (; minor < end; ++minor)
-                __clear_bit(minor, minors);
+        bitmap_clear(minors,  minor, nr);
         spin_unlock(&minor_lock);
 }
 
@@ -419,7 +417,7 @@ static int xlvbd_init_blk_queue(struct gendisk *gd, u16 sector_size)
         struct request_queue *rq;
         struct blkfront_info *info = gd->private_data;
 
-        rq = blk_init_queue(do_blkif_request, &blkif_io_lock);
+        rq = blk_init_queue(do_blkif_request, &info->io_lock);
         if (rq == NULL)
                 return -1;
 
@@ -636,14 +634,14 @@ static void xlvbd_release_gendisk(struct blkfront_info *info)
         if (info->rq == NULL)
                 return;
 
-        spin_lock_irqsave(&blkif_io_lock, flags);
+        spin_lock_irqsave(&info->io_lock, flags);
 
         /* No more blkif_request(). */
         blk_stop_queue(info->rq);
 
         /* No more gnttab callback work. */
         gnttab_cancel_free_callback(&info->callback);
-        spin_unlock_irqrestore(&blkif_io_lock, flags);
+        spin_unlock_irqrestore(&info->io_lock, flags);
 
         /* Flush gnttab callback work. Must be done with no locks held. */
         flush_work_sync(&info->work);
@@ -675,16 +673,16 @@ static void blkif_restart_queue(struct work_struct *work)
 {
         struct blkfront_info *info = container_of(work, struct blkfront_info, work);
 
-        spin_lock_irq(&blkif_io_lock);
+        spin_lock_irq(&info->io_lock);
         if (info->connected == BLKIF_STATE_CONNECTED)
                 kick_pending_request_queues(info);
-        spin_unlock_irq(&blkif_io_lock);
+        spin_unlock_irq(&info->io_lock);
 }
 
 static void blkif_free(struct blkfront_info *info, int suspend)
 {
         /* Prevent new requests being issued until we fix things up. */
-        spin_lock_irq(&blkif_io_lock);
+        spin_lock_irq(&info->io_lock);
         info->connected = suspend ?
                 BLKIF_STATE_SUSPENDED : BLKIF_STATE_DISCONNECTED;
         /* No more blkif_request(). */
@@ -692,7 +690,7 @@ static void blkif_free(struct blkfront_info *info, int suspend)
                 blk_stop_queue(info->rq);
         /* No more gnttab callback work. */
         gnttab_cancel_free_callback(&info->callback);
-        spin_unlock_irq(&blkif_io_lock);
+        spin_unlock_irq(&info->io_lock);
 
         /* Flush gnttab callback work. Must be done with no locks held. */
         flush_work_sync(&info->work);
@@ -728,10 +726,10 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
         struct blkfront_info *info = (struct blkfront_info *)dev_id;
         int error;
 
-        spin_lock_irqsave(&blkif_io_lock, flags);
+        spin_lock_irqsave(&info->io_lock, flags);
 
         if (unlikely(info->connected != BLKIF_STATE_CONNECTED)) {
-                spin_unlock_irqrestore(&blkif_io_lock, flags);
+                spin_unlock_irqrestore(&info->io_lock, flags);
                 return IRQ_HANDLED;
         }
 
@@ -816,7 +814,7 @@ static irqreturn_t blkif_interrupt(int irq, void *dev_id)
 
         kick_pending_request_queues(info);
 
-        spin_unlock_irqrestore(&blkif_io_lock, flags);
+        spin_unlock_irqrestore(&info->io_lock, flags);
 
         return IRQ_HANDLED;
 }
@@ -991,6 +989,7 @@ static int blkfront_probe(struct xenbus_device *dev,
         }
 
         mutex_init(&info->mutex);
+        spin_lock_init(&info->io_lock);
         info->xbdev = dev;
         info->vdevice = vdevice;
         info->connected = BLKIF_STATE_DISCONNECTED;
@@ -1068,7 +1067,7 @@ static int blkif_recover(struct blkfront_info *info)
 
         xenbus_switch_state(info->xbdev, XenbusStateConnected);
 
-        spin_lock_irq(&blkif_io_lock);
+        spin_lock_irq(&info->io_lock);
 
         /* Now safe for us to use the shared ring */
         info->connected = BLKIF_STATE_CONNECTED;
@@ -1079,7 +1078,7 @@ static int blkif_recover(struct blkfront_info *info)
         /* Kick any other new requests queued since we resumed */
         kick_pending_request_queues(info);
 
-        spin_unlock_irq(&blkif_io_lock);
+        spin_unlock_irq(&info->io_lock);
 
         return 0;
 }
@@ -1277,10 +1276,10 @@ static void blkfront_connect(struct blkfront_info *info)
         xenbus_switch_state(info->xbdev, XenbusStateConnected);
 
         /* Kick pending requests. */
-        spin_lock_irq(&blkif_io_lock);
+        spin_lock_irq(&info->io_lock);
         info->connected = BLKIF_STATE_CONNECTED;
         kick_pending_request_queues(info);
-        spin_unlock_irq(&blkif_io_lock);
+        spin_unlock_irq(&info->io_lock);
 
         add_disk(info->gd);
 
@@ -1410,7 +1409,6 @@ static int blkif_release(struct gendisk *disk, fmode_t mode)
         mutex_lock(&blkfront_mutex);
 
         bdev = bdget_disk(disk, 0);
-        bdput(bdev);
 
         if (bdev->bd_openers)
                 goto out;
@@ -1441,6 +1439,7 @@ static int blkif_release(struct gendisk *disk, fmode_t mode)
         }
 
 out:
+        bdput(bdev);
         mutex_unlock(&blkfront_mutex);
         return 0;
 }