Helper function bpf_kptr_xchg
Definition
Copyright (c) 2015 The Libbpf Authors. All rights reserved.
Exchange kptr at pointer map_value with ptr, and return the old value. ptr can be NULL, otherwise it must be a referenced pointer which will be released when this helper is called.
Returns
The old value of kptr (which can be NULL). The returned pointer if not NULL, is a reference which must be released using its corresponding release function, or moved into a BPF map before program exit.
static void *(* const bpf_kptr_xchg)(void *map_value, void *ptr) = (void *) 194;
Usage
Docs could be improved
This part of the docs is incomplete, contributions are very welcome
Program types
This helper call can be used in the following program types:
BPF_PROG_TYPE_CGROUP_DEVICE
BPF_PROG_TYPE_CGROUP_SKB
BPF_PROG_TYPE_CGROUP_SOCK
BPF_PROG_TYPE_CGROUP_SOCKOPT
BPF_PROG_TYPE_CGROUP_SOCK_ADDR
BPF_PROG_TYPE_CGROUP_SYSCTL
BPF_PROG_TYPE_FLOW_DISSECTOR
BPF_PROG_TYPE_KPROBE
BPF_PROG_TYPE_LSM
BPF_PROG_TYPE_LWT_IN
BPF_PROG_TYPE_LWT_OUT
BPF_PROG_TYPE_LWT_SEG6LOCAL
BPF_PROG_TYPE_LWT_XMIT
BPF_PROG_TYPE_NETFILTER
BPF_PROG_TYPE_PERF_EVENT
BPF_PROG_TYPE_RAW_TRACEPOINT
BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE
BPF_PROG_TYPE_SCHED_ACT
BPF_PROG_TYPE_SCHED_CLS
BPF_PROG_TYPE_SK_LOOKUP
BPF_PROG_TYPE_SK_MSG
BPF_PROG_TYPE_SK_REUSEPORT
BPF_PROG_TYPE_SK_SKB
BPF_PROG_TYPE_SOCKET_FILTER
BPF_PROG_TYPE_SOCK_OPS
BPF_PROG_TYPE_STRUCT_OPS
BPF_PROG_TYPE_SYSCALL
BPF_PROG_TYPE_TRACEPOINT
BPF_PROG_TYPE_TRACING
BPF_PROG_TYPE_XDP
Example
Docs could be improved
This part of the docs is incomplete, contributions are very welcome