The user must communicate the parameters utilized with its construction out-of-band but can otherwise use an existing file descriptor. The library will then map the existing ring's queues. This permits using a pre-opened file descriptor such as one shared by a parent process, or one stashed away to be kept open in systemd's file descriptor store.
Keeping a ring open can allow its operations to complete despite the writer's process dying unexpectedly. Additionally, another process might register a personality (IORING_REGISTER_PERSONALITY) to be used as means of effective access controls for operations that must avoid confused deputy scenarios. A ring opened by a parent might also have pre-existing trusted restrictions (IORING_REGISTER_RESTRICTIONS) applied to it.
Note that this is not an implementation of IORING_SETUP_ATTACH_WQ or of a multi-issuer submission queue.
quininer
commented
4 months ago
The user must communicate the parameters utilized with its construction out-of-band but can otherwise use an existing file descriptor. The library will then map the existing ring's queues. This permits using a pre-opened file descriptor such as one shared by a parent process, or one stashed away to be kept open in systemd's file descriptor store.
Keeping a ring open can allow its operations to complete despite the writer's process dying unexpectedly. Additionally, another process might register a personality (IORING_REGISTER_PERSONALITY) to be used as means of effective access controls for operations that must avoid confused deputy scenarios. A ring opened by a parent might also have pre-existing trusted restrictions (IORING_REGISTER_RESTRICTIONS) applied to it.
Note that this is not an implementation of
IORING_SETUP_ATTACH_WQor of a multi-issuer submission queue.