1 /* 2 * Copyright 2018 Google, Inc 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 #include <errno.h> 18 #include <fcntl.h> 19 #include <sys/cdefs.h> 20 #include <sys/stat.h> 21 #include <sys/types.h> 22 #include <stdio.h> 23 #include <unistd.h> 24 25 #include <liblmkd_utils.h> 26 #include <cutils/sockets.h> 27 28 int lmkd_connect() { 29 return socket_local_client("lmkd", 30 ANDROID_SOCKET_NAMESPACE_RESERVED, 31 SOCK_SEQPACKET); 32 } 33 34 int lmkd_register_proc(int sock, struct lmk_procprio *params) { 35 LMKD_CTRL_PACKET packet; 36 size_t size; 37 int ret; 38 39 size = lmkd_pack_set_procprio(packet, params); 40 ret = TEMP_FAILURE_RETRY(write(sock, packet, size)); 41 42 return (ret < 0) ? -1 : 0; 43 } 44 45 int create_memcg(uid_t uid, pid_t pid) { 46 char buf[256]; 47 int tasks_file; 48 int written; 49 50 snprintf(buf, sizeof(buf), "/dev/memcg/apps/uid_%u", uid); 51 if (mkdir(buf, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH) < 0 && 52 errno != EEXIST) { 53 return -1; 54 } 55 56 snprintf(buf, sizeof(buf), "/dev/memcg/apps/uid_%u/pid_%u", uid, pid); 57 if (mkdir(buf, S_IRWXU | S_IRWXG | S_IROTH | S_IXOTH) < 0 && 58 errno != EEXIST) { 59 return -1; 60 } 61 62 snprintf(buf, sizeof(buf), "/dev/memcg/apps/uid_%u/pid_%u/tasks", uid, pid); 63 tasks_file = open(buf, O_WRONLY); 64 if (tasks_file < 0) { 65 return -2; 66 } 67 written = snprintf(buf, sizeof(buf), "%u", pid); 68 if (__predict_false(written >= (int)sizeof(buf))) { 69 written = sizeof(buf) - 1; 70 } 71 written = TEMP_FAILURE_RETRY(write(tasks_file, buf, written)); 72 close(tasks_file); 73 74 return (written < 0) ? -3 : 0; 75 } 76 77
