fs: add generic_llseek_cookie()

This is similar to generic_file_llseek() but allows the caller to
specify a cookie that will be updated to indicate that a seek happened.
Caller's requiring that information in their readdir implementations can
use that.

Link: https://lore.kernel.org/r/[email protected]
Reviewed-by: Jan Kara <[email protected]>
Reviewed-by: Jeff Layton <[email protected]>
Signed-off-by: Christian Brauner <[email protected]>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 58c91a52cad1..3e6b3c1afb31 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3202,6 +3202,8 @@ extern loff_t vfs_setpos(struct file *file, loff_t offset, loff_t maxsize);
 extern loff_t generic_file_llseek(struct file *file, loff_t offset, int whence);
 extern loff_t generic_file_llseek_size(struct file *file, loff_t offset,
 		int whence, loff_t maxsize, loff_t eof);
+loff_t generic_llseek_cookie(struct file *file, loff_t offset, int whence,
+			     u64 *cookie);
 extern loff_t fixed_size_llseek(struct file *file, loff_t offset,
 		int whence, loff_t size);
 extern loff_t no_seek_end_llseek_size(struct file *, loff_t, int, loff_t);