clean up write_begin usage for directories in pagecache

For filesystem that implement directories in pagecache we call
block_write_begin with an already allocated page for this code, while the
normal regular file write path uses the default block_write_begin behaviour.

Get rid of the __foofs_write_begin helper and opencode the normal write_begin
call in foofs_write_begin, while adding a new foofs_prepare_chunk helper for
the directory code.  The added benefit is that foofs_prepare_chunk has
a much saner calling convention.

Note that the interruptible flag passed into block_write_begin is always
ignored if we already pass in a page (see next patch for details), and
we never were doing truncations of exessive blocks for this case either so we
can switch directly to block_write_begin_newtrunc.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 1 insertions, 3 deletions

diff --git a/fs/minix/minix.h b/fs/minix/minix.h
index 111f34ee9e3b..407b1c84911e 100644
--- a/fs/minix/minix.h
+++ b/fs/minix/minix.h
@@ -53,9 +53,7 @@ extern int minix_new_block(struct inode * inode);
 extern void minix_free_block(struct inode *inode, unsigned long block);
 extern unsigned long minix_count_free_blocks(struct minix_sb_info *sbi);
 extern int minix_getattr(struct vfsmount *, struct dentry *, struct kstat *);
-extern int __minix_write_begin(struct file *file, struct address_space *mapping,
-			loff_t pos, unsigned len, unsigned flags,
-			struct page **pagep, void **fsdata);
+extern int minix_prepare_chunk(struct page *page, loff_t pos, unsigned len);
 
 extern void V1_minix_truncate(struct inode *);
 extern void V2_minix_truncate(struct inode *);