1 // SPDX-License-Identifier: GPL-2.0 2 3 #define _GNU_SOURCE 4 #include <fcntl.h> 5 #include <assert.h> 6 #include <stdio.h> 7 #include <unistd.h> 8 #include <string.h> 9 #include "../kselftest.h" 10 11 static int lock_set(int fd, struct flock *fl) 12 { 13 int ret; 14 15 fl->l_pid = 0; // needed for OFD locks 16 fl->l_whence = SEEK_SET; 17 ret = fcntl(fd, F_OFD_SETLK, fl); 18 if (ret) 19 perror("fcntl()"); 20 return ret; 21 } 22 23 static int lock_get(int fd, struct flock *fl) 24 { 25 int ret; 26 27 fl->l_pid = 0; // needed for OFD locks 28 fl->l_whence = SEEK_SET; 29 ret = fcntl(fd, F_OFD_GETLK, fl); 30 if (ret) 31 perror("fcntl()"); 32 return ret; 33 } 34 35 int main(void) 36 { 37 int rc; 38 struct flock fl, fl2; 39 int fd = open("/tmp/aa", O_RDWR | O_CREAT | O_EXCL, 0600); 40 int fd2 = open("/tmp/aa", O_RDONLY); 41 42 unlink("/tmp/aa"); 43 assert(fd != -1); 44 assert(fd2 != -1); 45 ksft_print_msg("[INFO] opened fds %i %i\n", fd, fd2); 46 47 /* Set some read lock */ 48 fl.l_type = F_RDLCK; 49 fl.l_start = 5; 50 fl.l_len = 3; 51 rc = lock_set(fd, &fl); 52 if (rc == 0) { 53 ksft_print_msg 54 ("[SUCCESS] set OFD read lock on first fd\n"); 55 } else { 56 ksft_print_msg("[FAIL] to set OFD read lock on first fd\n"); 57 return -1; 58 } 59 /* Make sure read locks do not conflict on different fds. */ 60 fl.l_type = F_RDLCK; 61 fl.l_start = 5; 62 fl.l_len = 1; 63 rc = lock_get(fd2, &fl); 64 if (rc != 0) 65 return -1; 66 if (fl.l_type != F_UNLCK) { 67 ksft_print_msg("[FAIL] read locks conflicted\n"); 68 return -1; 69 } 70 /* Make sure read/write locks do conflict on different fds. */ 71 fl.l_type = F_WRLCK; 72 fl.l_start = 5; 73 fl.l_len = 1; 74 rc = lock_get(fd2, &fl); 75 if (rc != 0) 76 return -1; 77 if (fl.l_type != F_UNLCK) { 78 ksft_print_msg 79 ("[SUCCESS] read and write locks conflicted\n"); 80 } else { 81 ksft_print_msg 82 ("[SUCCESS] read and write locks not conflicted\n"); 83 return -1; 84 } 85 /* Get info about the lock on first fd. */ 86 fl.l_type = F_UNLCK; 87 fl.l_start = 5; 88 fl.l_len = 1; 89 rc = lock_get(fd, &fl); 90 if (rc != 0) { 91 ksft_print_msg 92 ("[FAIL] F_OFD_GETLK with F_UNLCK not supported\n"); 93 return -1; 94 } 95 if (fl.l_type != F_UNLCK) { 96 ksft_print_msg 97 ("[SUCCESS] F_UNLCK test returns: locked, type %i pid %i len %zi\n", 98 fl.l_type, fl.l_pid, fl.l_len); 99 } else { 100 ksft_print_msg 101 ("[FAIL] F_OFD_GETLK with F_UNLCK did not return lock info\n"); 102 return -1; 103 } 104 /* Try the same but by locking everything by len==0. */ 105 fl2.l_type = F_UNLCK; 106 fl2.l_start = 0; 107 fl2.l_len = 0; 108 rc = lock_get(fd, &fl2); 109 if (rc != 0) { 110 ksft_print_msg 111 ("[FAIL] F_OFD_GETLK with F_UNLCK not supported\n"); 112 return -1; 113 } 114 if (memcmp(&fl, &fl2, sizeof(fl))) { 115 ksft_print_msg 116 ("[FAIL] F_UNLCK test returns: locked, type %i pid %i len %zi\n", 117 fl.l_type, fl.l_pid, fl.l_len); 118 return -1; 119 } 120 ksft_print_msg("[SUCCESS] F_UNLCK with len==0 returned the same\n"); 121 /* Get info about the lock on second fd - no locks on it. */ 122 fl.l_type = F_UNLCK; 123 fl.l_start = 0; 124 fl.l_len = 0; 125 lock_get(fd2, &fl); 126 if (fl.l_type != F_UNLCK) { 127 ksft_print_msg 128 ("[FAIL] F_OFD_GETLK with F_UNLCK return lock info from another fd\n"); 129 return -1; 130 } 131 return 0; 132 } 133