IBV_OPEN_DEVICE(3)

💖 IBV_OPEN_DEVICE 💖

okay bestie, welcome to ibv_open_device and ibv_close_device — the glow-up-and-glow-down of RDMA device contexts. this is from the Libibverbs Programmer's Manual, and it's literally the front door of the whole verbs situation. you open a device, you get a context, you do stuff, you close it. iconic. 👑

✨ NAME ✨

ibv_open_device, ibv_close_device — open and close an RDMA device context 🦋

🌸 SYNOPSIS 🌸

#include <infiniband/verbs.h>

struct ibv_context *ibv_open_device(struct ibv_device *device);

int ibv_close_device(struct ibv_context *context);

💅 DESCRIPTION 💅

ibv_open_device() opens the device device and creates a context for further use. it's giving "hi yes i'd like to actually use this hardware please". ✨

ibv_close_device() closes the device context context. bye bestie, thank u for ur service. 🫶

🎀 RETURN VALUE 🎀

ibv_open_device() returns a pointer to the allocated device context, or NULL if the request fails. so like, check for NULL fr fr, don't just rawdog that pointer. 😭

ibv_close_device() returns 0 on success, -1 on failure. classic.

🔥 NOTES 🔥

lowkey the most important part, bestie, pay attention 👀

ibv_close_device() does not release all the resources allocated using context context. to avoid resource leaks, the user should release all associated resources before closing a context. that's a whole lot of cleanup you gotta do yourself — the close is not gonna do it for you, it's not your mom. 💀

setting the environment variable RDMAV_ALLOW_DISASSOC_DESTROY tells the library to relate an EIO from destroy commands as a success, as the kernel resources were already released. this comes to prevent memory leakage in the user space area upon device disassociation. applications using this flag cannot call ibv_get_cq_event or ibv_get_async_event concurrently with any call to an object destruction function. no cap, that concurrency thing is a hard no — don't do it. 🚫

🌈 SEE ALSO 🌈

• ibv_get_device_list(3)
• ibv_query_device(3)
• ibv_query_port(3)
• ibv_query_gid(3)
• ibv_query_pkey(3)

👑 AUTHORS 👑

Dotan Barak <dotanba@gmail.com>

and that's the whole page, bestie!! this one came from libibverbs, dated 2006-10-31, and you're reading the IBV_OPEN_DEVICE(3) page. go forth and open ur devices responsibly 💜✨