# gizhw:rdma

RDMA devices through libibverbs (libibverbs.so.1, loaded at run time): each device's name, firmware, node GUID and ids, and each port's state, MTU, LID, link width and speed, and link layer. The struct layouts are those of rdma-core's verbs.h (ibv_device_attr 232 bytes, ibv_port_attr 52 bytes), read by offset; the library's own functions do all the work.

```gizlang
import * as Rdma from "gizhw:rdma";
```

## Types

### `Port`

```gizlang
type Port = { number: i64; state: i64; mtu: i64; lid: i64; width: i64; speed: i64; linkLayer: i64; }
```

One port: its number, state (IBV_PORT_* 1 down, 2 init, 3 armed, 4 active), active MTU (IBV_MTU_*: 1 to 5 for 256 to
4096 bytes), LID, active width and speed (the IBV_WIDTH_* and IBV_SPEED_* codes), and link layer (IBV_LINK_LAYER_*:
1 InfiniBand, 2 Ethernet).

- `number`: `i64`
- `state`: `i64`
- `mtu`: `i64`
- `lid`: `i64`
- `width`: `i64`
- `speed`: `i64`
- `linkLayer`: `i64`

### `RdmaDevice`

```gizlang
type RdmaDevice = { name: string; firmware: string; guid: u64; vendor: i64; part: i64; hardware: i64; ports: Vec<Port>; }
```

One RDMA device: its name, firmware version, node GUID, vendor and part ids, hardware revision, and its ports.

- `name`: `string`
- `firmware`: `string`
- `guid`: `u64`
- `vendor`: `i64`
- `part`: `i64`
- `hardware`: `i64`
- `ports`: `Vec<M15.Port>`

## Functions

### `parseDevice`

```gizlang
function parseDevice(data: bytes, name: string, ports: Vec<Port>): RdmaDevice
```

The device from its ibv_device_attr reply, its name and its ports (the name is not in the struct).

Effects: fail.

### `portCount`

```gizlang
function portCount(data: bytes): i64
```

The number of physical ports in an ibv_device_attr reply.

Effects: fail.

### `parsePort`

```gizlang
function parsePort(data: bytes, number: i64): Port
```

The port from its ibv_port_attr reply, numbered `number`.

Effects: fail.

### `devices`

```gizlang
function devices(sys: System): Vec<RdmaDevice> throws string
```

The RDMA devices the verbs library lists, with their ports. A device that cannot be opened is left out.

Effects: fail, io.