Merge tag 'v3.7-rc6' into asoc-wm2200

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

diff --git a/fs/block_dev.c b/fs/block_dev.c
index b3c1d3d..1a1e5e3 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1661,6 +1661,39 @@ static int blkdev_mmap(struct file *file, struct vm_area_struct *vma)
        return ret;
 }
 
+static ssize_t blkdev_splice_read(struct file *file, loff_t *ppos,
+                                 struct pipe_inode_info *pipe, size_t len,
+                                 unsigned int flags)
+{
+       ssize_t ret;
+       struct block_device *bdev = I_BDEV(file->f_mapping->host);
+
+       percpu_down_read(&bdev->bd_block_size_semaphore);
+
+       ret = generic_file_splice_read(file, ppos, pipe, len, flags);
+
+       percpu_up_read(&bdev->bd_block_size_semaphore);
+
+       return ret;
+}
+
+static ssize_t blkdev_splice_write(struct pipe_inode_info *pipe,
+                                  struct file *file, loff_t *ppos, size_t len,
+                                  unsigned int flags)
+{
+       ssize_t ret;
+       struct block_device *bdev = I_BDEV(file->f_mapping->host);
+
+       percpu_down_read(&bdev->bd_block_size_semaphore);
+
+       ret = generic_file_splice_write(pipe, file, ppos, len, flags);
+
+       percpu_up_read(&bdev->bd_block_size_semaphore);
+
+       return ret;
+}
+
+
 /*
  * Try to release a page associated with block device when the system
  * is under memory pressure.
@@ -1699,8 +1732,8 @@ const struct file_operations def_blk_fops = {
 #ifdef CONFIG_COMPAT
        .compat_ioctl   = compat_blkdev_ioctl,
 #endif
-       .splice_read    = generic_file_splice_read,
-       .splice_write   = generic_file_splice_write,
+       .splice_read    = blkdev_splice_read,
+       .splice_write   = blkdev_splice_write,
 };
 
 int ioctl_by_bdev(struct block_device *bdev, unsigned cmd, unsigned long arg)