man/io_uring_register.2: add note of ring quiesce for file/buffers registration
@@ -89,6 +89,10 @@ then issuing a new call to
.BR io_uring_register ()
with the new buffers.
+Note that registering buffers will wait for the ring to idle. If the application
+currently has requests in-flight, the registration will wait for those to
+finish before proceeding.
+
An application need not unregister buffers explicitly before shutting
down the io_uring instance. Available since 5.1.
@@ -117,6 +121,20 @@ and the
.I fd
member is set to the index of the file in the file descriptor array.
+The file set may be sparse, meaning that the
+.B fd
+field in the array may be set to
+.B -1.
+See
+.B IORING_REGISTER_FILES_UPDATE
+for how to update files in place.
+
+Note that registering files will wait for the ring to idle. If the application
+currently has requests in-flight, the registration will wait for those to
+finish before proceeding. See
+.B IORING_REGISTER_FILES_UPDATE
+for how to update an existing set without that limitation.
+
Files are automatically unregistered when the io_uring instance is
torn down. An application need only unregister if it wishes to
register a new set of fds. Available since 5.1.
