FIx

Signed-off-by: Xuanwo <[email protected]>

core/src/docs/rfcs/4382_range_based_read.md

@@ -30,6 +30,7 @@ However, after observing our users, we found that:
 
 - `AsyncSeek` in `Reader` is prone to misuse.
 - `Reader` does not support concurrent reading.
+- `Reader` can't adopt Completion-based IO
 
 ## Misuse of `AsyncSeek`
 
@@ -43,6 +44,10 @@ For example, `s3` storage does not support `seek` natively. When users call `see
 
 There is no way for opendal to support this feature.
 
+## Can't adopt Completion-based IO
+
+Completion-based IO requires take the buffer's owner ship. But API that take `&mut [u8]` can't do that.
+
 # Guide-level explanation
 
 So I propose to convert `Reader` into a stateless, range-based reading pattern.