sendfile: kill generic_file_sendfile()

		unsigned long, loff_t, loff_t *, size_t, ssize_t);

extern ssize_t do_sync_read(struct file *filp, char __user *buf, size_t len, loff_t *ppos);

extern ssize_t do_sync_write(struct file *filp, const char __user *buf, size_t len, loff_t *ppos);

extern ssize_t generic_file_sendfile(struct file *, loff_t *, size_t, read_actor_t, void *);

extern void do_generic_mapping_read(struct address_space *mapping,

				    struct file_ra_state *, struct file *,

				    loff_t *, read_descriptor_t *, read_actor_t);

	return written;

}

ssize_t generic_file_sendfile(struct file *in_file, loff_t *ppos,

			 size_t count, read_actor_t actor, void *target)

{

	read_descriptor_t desc;

	if (!count)

		return 0;

	desc.written = 0;

	desc.count = count;

	desc.arg.data = target;

	desc.error = 0;

	do_generic_file_read(in_file, ppos, &desc, actor);

	if (desc.written)

		return desc.written;

	return desc.error;

}

EXPORT_SYMBOL(generic_file_sendfile);

static ssize_t

do_readahead(struct address_space *mapping, struct file *filp,

	     unsigned long index, unsigned long nr)