CIFS: Simplify invalidate part (try #5)

[cascardo/linux.git] / fs / block_dev.c

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 7d02afb..257b00e 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -55,11 +55,13 @@ EXPORT_SYMBOL(I_BDEV);
 static void bdev_inode_switch_bdi(struct inode *inode,
                        struct backing_dev_info *dst)
 {
-       spin_lock(&inode_lock);
+       spin_lock(&inode_wb_list_lock);
+       spin_lock(&inode->i_lock);
        inode->i_data.backing_dev_info = dst;
        if (inode->i_state & I_DIRTY)
                list_move(&inode->i_wb_list, &dst->wb.b_dirty);
-       spin_unlock(&inode_lock);
+       spin_unlock(&inode->i_lock);
+       spin_unlock(&inode_wb_list_lock);
 }
 
 static sector_t max_block(struct block_device *bdev)
@@ -651,7 +653,7 @@ void bd_forget(struct inode *inode)
  * @whole: whole block device containing @bdev, may equal @bdev
  * @holder: holder trying to claim @bdev
  *
- * Test whther @bdev can be claimed by @holder.
+ * Test whether @bdev can be claimed by @holder.
  *
  * CONTEXT:
  * spin_lock(&bdev_lock).
@@ -1100,6 +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) {
@@ -1116,9 +1119,18 @@ 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 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;
+
                        if (!bdev->bd_openers) {
                                bd_set_size(bdev,(loff_t)get_capacity(disk)<<9);
                                bdi = blk_get_backing_dev_info(bdev);
@@ -1126,8 +1138,6 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
                                        bdi = &default_backing_dev_info;
                                bdev_inode_switch_bdi(bdev->bd_inode, bdi);
                        }
-                       if (bdev->bd_invalidated)
-                               rescan_partitions(disk, bdev);
                } else {
                        struct block_device *whole;
                        whole = bdget_disk(disk, 0);
@@ -1151,13 +1161,14 @@ 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);