1 /******************************************************************************/ 2 /* Copyright (c) Crackerjack Project., 2007 */ 3 /* */ 4 /* This program is free software; you can redistribute it and/or modify */ 5 /* it under the terms of the GNU General Public License as published by */ 6 /* the Free Software Foundation; either version 2 of the License, or */ 7 /* (at your option) any later version. */ 8 /* */ 9 /* This program is distributed in the hope that it will be useful, */ 10 /* but WITHOUT ANY WARRANTY; without even the implied warranty of */ 11 /* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See */ 12 /* the GNU General Public License for more details. */ 13 /* */ 14 /* You should have received a copy of the GNU General Public License */ 15 /* along with this program; if not, write to the Free Software */ 16 /* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA */ 17 /* */ 18 /******************************************************************************/ 19 /******************************************************************************/ 20 /* */ 21 /* File: bdflush01.c */ 22 /* */ 23 /* Description: bdflush() starts, flushes, or tunes the buffer-dirty-flush */ 24 /* daemon. Only a privileged process (one with the CAP_SYS_ADMIN */ 25 /* capability) may call bdflush(). */ 26 /* */ 27 /* If func is negative or 0, and no daemon has been started, */ 28 /* then bdflush() enters the daemon code and never returns. */ 29 /* */ 30 /* If func is 1, some dirty buffers are written to disk. */ 31 /* If func is 2 or more and is even (low bit is 0), then address */ 32 /* is the address of a long word, and the tuning parameter */ 33 /* numbered (func-2)/2 is returned to the caller in that address.*/ 34 /* */ 35 /* If func is 3 or more and is odd (low bit is 1), then data is */ 36 /* a long word, and the kernel sets tuning parameter numbered */ 37 /* (func-3)/2 to that value. */ 38 /* */ 39 /* The set of parameters, their values, and their legal ranges */ 40 /* are defined in the kernel source file fs/buffer.c. */ 41 /* */ 42 /* Return Value: */ 43 /* If func is negative or 0 and the daemon successfully starts, */ 44 /* bdflush() never returns. Otherwise, the return value is 0 on */ 45 /* success and -1 on failure, with errno set to indicate the */ 46 /* error. */ 47 /* */ 48 /* Errors: */ 49 /* EBUSY */ 50 /* An attempt was made to enter the daemon code after*/ 51 /* another process has already entered. */ 52 /* EFAULT */ 53 /* address points outside your accessible address */ 54 /* space. */ 55 /* EINVAL */ 56 /* An attempt was made to read or write an invalid */ 57 /* parameter number, or to write an invalid value to */ 58 /* a parameter. */ 59 /* EPERM */ 60 /* Caller does not have the CAP_SYS_ADMIN capability.*/ 61 /* */ 62 /* Usage: <for command-line> */ 63 /* bdflush01 [-c n] [-e][-i n] [-I x] [-p x] [-t] */ 64 /* where, -c n : Run n copies concurrently. */ 65 /* -e : Turn on errno logging. */ 66 /* -i n : Execute test n times. */ 67 /* -I x : Execute test for x seconds. */ 68 /* -P x : Pause for x seconds between iterations. */ 69 /* -t : Turn on syscall timing. */ 70 /* */ 71 /* Total Tests: 1 */ 72 /* */ 73 /* Test Name: bdflush01 */ 74 /* History: Porting from Crackerjack to LTP is done by */ 75 /* Manas Kumar Nayak maknayak (at) in.ibm.com> */ 76 /******************************************************************************/ 77 #include <stdio.h> 78 #include <stdlib.h> 79 #include <sys/wait.h> 80 #include <sys/types.h> 81 #include <unistd.h> 82 #include <errno.h> 83 #include <sys/stat.h> 84 85 #include "test.h" 86 #include "lapi/syscalls.h" 87 88 char *TCID = "bdflush01"; 89 int testno; 90 int TST_TOTAL = 1; 91 92 void cleanup(void) 93 { 94 tst_rmdir(); 95 } 96 97 void setup(void) 98 { 99 TEST_PAUSE; 100 tst_tmpdir(); 101 } 102 103 int main(int ac, char **av) 104 { 105 long data; 106 107 tst_parse_opts(ac, av, NULL, NULL); 108 109 setup(); 110 111 /* 112 * TODO (garrcoop): add more functional testcases; there are a ton 113 * missing. 114 */ 115 data = 0; 116 tst_count = 1; 117 for (testno = 0; testno < TST_TOTAL; ++testno) { 118 TEST(ltp_syscall(__NR_bdflush, 3, data)); 119 if (TEST_RETURN == -1) 120 tst_brkm(TFAIL | TTERRNO, cleanup, "bdflush failed"); 121 else 122 tst_resm(TPASS, "bdflush() = %ld", TEST_RETURN); 123 } 124 cleanup(); 125 tst_exit(); 126 } 127
