Merge branch 'omap-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tmlind...

[pandora-kernel.git] / fs / block_dev.c

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 5147bdd..1f2b199 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1102,6 +1102,7 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                        if (!bdev->bd_part)
                                goto out_clear;
 
+                       ret = 0;
                        if (disk->fops->open) {
                                ret = disk->fops->open(bdev, mode);
                                if (ret == -ERESTARTSYS) {
@@ -1118,18 +1119,26 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                                        put_disk(disk);
                                        goto restart;
                                }
-                               if (ret)
-                                       goto out_clear;
                        }
-                       if (!bdev->bd_openers) {
+
+                       if (!ret && !bdev->bd_openers) {
                                bd_set_size(bdev,(loff_t)get_capacity(disk)<<9);
                                bdi = blk_get_backing_dev_info(bdev);
                                if (bdi == NULL)
                                        bdi = &default_backing_dev_info;
                                bdev_inode_switch_bdi(bdev->bd_inode, bdi);
                        }
-                       if (bdev->bd_invalidated)
+
+                       /*
+                        * If the device is invalidated, rescan partition
+                        * if open succeeded or failed with -ENOMEDIUM.
+                        * The latter is necessary to prevent ghost
+                        * partitions on a removed medium.
+                        */
+                       if (bdev->bd_invalidated && (!ret || ret == -ENOMEDIUM))
                                rescan_partitions(disk, bdev);
+                       if (ret)
+                               goto out_clear;
                } else {
                        struct block_device *whole;
                        whole = bdget_disk(disk, 0);
@@ -1153,13 +1162,14 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                }
        } else {
                if (bdev->bd_contains == bdev) {
-                       if (bdev->bd_disk->fops->open) {
+                       ret = 0;
+                       if (bdev->bd_disk->fops->open)
                                ret = bdev->bd_disk->fops->open(bdev, mode);
-                               if (ret)
-                                       goto out_unlock_bdev;
-                       }
-                       if (bdev->bd_invalidated)
+                       /* the same as first opener case, read comment there */
+                       if (bdev->bd_invalidated && (!ret || ret == -ENOMEDIUM))
                                rescan_partitions(bdev->bd_disk, bdev);
+                       if (ret)
+                               goto out_unlock_bdev;
                }
                /* only one opener holds refs to the module and disk */
                module_put(disk->fops->owner);
@@ -1228,6 +1238,8 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder)
        res = __blkdev_get(bdev, mode, 0);
 
        if (whole) {
+               struct gendisk *disk = whole->bd_disk;
+
                /* finish claiming */
                mutex_lock(&bdev->bd_mutex);
                spin_lock(&bdev_lock);
@@ -1254,15 +1266,16 @@ int blkdev_get(struct block_device *bdev, fmode_t mode, void *holder)
                spin_unlock(&bdev_lock);
 
                /*
-                * Block event polling for write claims.  Any write
-                * holder makes the write_holder state stick until all
-                * are released.  This is good enough and tracking
-                * individual writeable reference is too fragile given
-                * the way @mode is used in blkdev_get/put().
+                * Block event polling for write claims if requested.  Any
+                * write holder makes the write_holder state stick until
+                * all are released.  This is good enough and tracking
+                * individual writeable reference is too fragile given the
+                * way @mode is used in blkdev_get/put().
                 */
-               if (!res && (mode & FMODE_WRITE) && !bdev->bd_write_holder) {
+               if ((disk->flags & GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE) &&
+                   !res && (mode & FMODE_WRITE) && !bdev->bd_write_holder) {
                        bdev->bd_write_holder = true;
-                       disk_block_events(bdev->bd_disk);
+                       disk_block_events(disk);
                }
 
                mutex_unlock(&bdev->bd_mutex);