[PATCH v4 01/22] fs: Add generic_atomic_write_valid_size()

John Garry
2024-06-07T14:40:13Z

Add a generic helper for FSes to validate that an atomic write is
appropriately sized (along with the other checks).

Signed-off-by: John Garry <john.g.garry@oracle.com>
---
include/linux/fs.h | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/include/linux/fs.h b/include/linux/fs.h
index 069cbab62700..e13d34f8c24e 100644
--- a/include/linux/fs.h
+++ b/include/linux/fs.h
@@ -3645,4 +3645,16 @@ bool generic_atomic_write_valid(loff_t pos, struct iov_iter *iter)
return true;
}

+static inline
+bool generic_atomic_write_valid_size(loff_t pos, struct iov_iter *iter,
+ unsigned int unit_min, unsigned int unit_max)
+{
+ size_t len = iov_iter_count(iter);
+
+ if (len < unit_min || len > unit_max)
+ return false;
+
+ return generic_atomic_write_valid(pos, iter);
+}
+
#endif /* _LINUX_FS_H */
--
2.31.1