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>
diff --git a/fs/sysv/sysv.h b/fs/sysv/sysv.h
index 94cb9b4..bb55cdb 100644
--- a/fs/sysv/sysv.h
+++ b/fs/sysv/sysv.h
@@ -136,9 +136,7 @@
/* itree.c */
extern void sysv_truncate(struct inode *);
-extern int __sysv_write_begin(struct file *file, struct address_space *mapping,
- loff_t pos, unsigned len, unsigned flags,
- struct page **pagep, void **fsdata);
+extern int sysv_prepare_chunk(struct page *page, loff_t pos, unsigned len);
/* inode.c */
extern struct inode *sysv_iget(struct super_block *, unsigned int);