Hi Jens,

After merging the block tree, today's linux-next build (powerpc
ppc64_defconfig) failed like this:

fs/block_dev.c: In function 'set_blocksize':
fs/block_dev.c:135:2: error: implicit declaration of function 'prio_tree_empty' [-Werror=implicit-function-declaration]

Caused by commit b87570f5d349 ("Fix a crash when block device is read and
block size is changed at the same time") interacting with commit
147e615f83c2 ("prio_tree: remove") which is now in Linus' tree.

I have added the following merge fix patch for today (this is a mash of
tow fix patches that used to be in Andrew's tree):

From: Andrew Morton <akpm@linux-foundation.org>
Subject: fs/block_dev.c:set_blocksize(): use mapping_mapped()

... instead of open-coding it.

Suggested-by: Mikulas Patocka <mpatocka@redhat.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

diff -puN fs/block_dev.c~fs-block_devc-set_blocksize-use-mapping_mapped fs/block_dev.c
--- a/fs/block_dev.c~fs-block_devc-set_blocksize-use-mapping_mapped
+++ a/fs/block_dev.c
@@ -132,8 +132,7 @@ int set_blocksize(struct block_device *b
 	/* Check that the block device is not memory mapped */
 	mapping = bdev->bd_inode->i_mapping;
 	mutex_lock(&mapping->i_mmap_mutex);
-	if (!prio_tree_empty(&mapping->i_mmap) ||
-	    !list_empty(&mapping->i_mmap_nonlinear)) {
+	if (mapping_mapped(mapping)) {
 		mutex_unlock(&mapping->i_mmap_mutex);
 		percpu_up_write(&bdev->bd_block_size_semaphore);
 		return -EBUSY;

-- 
Cheers,
Stephen Rothwell                    sfr@canb.auug.org.au