Merge tag 'for-torvalds-20120418' of git://git.kernel.org/pub/scm/linux/kernel/git...

[pandora-kernel.git] / drivers / block / xen-blkfront.c

diff --git a/drivers/block/xen-blkfront.c b/drivers/block/xen-blkfront.c
index d5e1ab9..4e86393 100644 (file)
--- 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;
 }
@@ -1475,7 +1474,7 @@ static int __init xlblk_init(void)
        if (!xen_domain())
                return -ENODEV;
 
-       if (!xen_platform_pci_unplug)
+       if (xen_hvm_domain() && !xen_platform_pci_unplug)
                return -ENODEV;
 
        if (register_blkdev(XENVBD_MAJOR, DEV_NAME)) {