| 1 | |
| 2 | |
| 3 | *
|
| 4 | * Copyright (C) 2023 SberDevices.
|
| 5 | *
|
| 6 | * Author: Arseniy Krasnov <[email protected]>
|
| 7 |
|
| 8 |
|
| 9 | #include <stdio.h>
|
| 10 | #include <stdlib.h>
|
| 11 | #include <sys/types.h>
|
| 12 | #include <sys/socket.h>
|
| 13 | #include <linux/errqueue.h>
|
| 14 |
|
| 15 | #include "msg_zerocopy_common.h"
|
| 16 |
|
| 17 | void vsock_recv_completion(int fd, const bool *zerocopied)
|
| 18 | {
|
| 19 | struct sock_extended_err *serr;
|
| 20 | struct msghdr msg = { 0 };
|
| 21 | char cmsg_data[128];
|
| 22 | struct cmsghdr *cm;
|
| 23 | ssize_t res;
|
| 24 |
|
| 25 | msg.msg_control = cmsg_data;
|
| 26 | msg.msg_controllen = sizeof(cmsg_data);
|
| 27 |
|
| 28 | res = recvmsg(fd, &msg, MSG_ERRQUEUE);
|
| 29 | if (res) {
|
| 30 | fprintf(stderr, "failed to read error queue: %zi\n", res);
|
| 31 | exit(EXIT_FAILURE);
|
| 32 | }
|
| 33 |
|
| 34 | cm = CMSG_FIRSTHDR(&msg);
|
| 35 | if (!cm) {
|
| 36 | fprintf(stderr, "cmsg: no cmsg\n");
|
| 37 | exit(EXIT_FAILURE);
|
| 38 | }
|
| 39 |
|
| 40 | if (cm->cmsg_level != SOL_VSOCK) {
|
| 41 | fprintf(stderr, "cmsg: unexpected 'cmsg_level'\n");
|
| 42 | exit(EXIT_FAILURE);
|
| 43 | }
|
| 44 |
|
| 45 | if (cm->cmsg_type != VSOCK_RECVERR) {
|
| 46 | fprintf(stderr, "cmsg: unexpected 'cmsg_type'\n");
|
| 47 | exit(EXIT_FAILURE);
|
| 48 | }
|
| 49 |
|
| 50 | serr = (void *)CMSG_DATA(cm);
|
| 51 | if (serr->ee_origin != SO_EE_ORIGIN_ZEROCOPY) {
|
| 52 | fprintf(stderr, "serr: wrong origin: %u\n", serr->ee_origin);
|
| 53 | exit(EXIT_FAILURE);
|
| 54 | }
|
| 55 |
|
| 56 | if (serr->ee_errno) {
|
| 57 | fprintf(stderr, "serr: wrong error code: %u\n", serr->ee_errno);
|
| 58 | exit(EXIT_FAILURE);
|
| 59 | }
|
| 60 |
|
| 61 | |
| 62 | * performed as expected: zerocopy or fallback to copy. If NULL
|
| 63 | * - don't care.
|
| 64 |
|
| 65 | if (!zerocopied)
|
| 66 | return;
|
| 67 |
|
| 68 | if (*zerocopied && (serr->ee_code & SO_EE_CODE_ZEROCOPY_COPIED)) {
|
| 69 | fprintf(stderr, "serr: was copy instead of zerocopy\n");
|
| 70 | exit(EXIT_FAILURE);
|
| 71 | }
|
| 72 |
|
| 73 | if (!*zerocopied && !(serr->ee_code & SO_EE_CODE_ZEROCOPY_COPIED)) {
|
| 74 | fprintf(stderr, "serr: was zerocopy instead of copy\n");
|
| 75 | exit(EXIT_FAILURE);
|
| 76 | }
|
| 77 | }
|