1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (c) 2004 Daniel McNeil <[email protected]>
4 * 2004 Open Source Development Lab
5 *
6 * Copyright (c) 2004 Marty Ridgeway <[email protected]>
7 *
8 * Copyright (c) 2011 Cyril Hrubis <[email protected]>
9 *
10 * Copyright (C) 2021 SUSE LLC Andrea Cervesato <[email protected]>
11 */
12
13 /*\
14 * [Description]
15 *
16 * Create a sparse file using O_DIRECT while other processes are doing
17 * buffered reads and check if the buffer reads always see zero.
18 */
19
20 #define _GNU_SOURCE
21
22 #include <stdlib.h>
23 #include <unistd.h>
24 #include <string.h>
25 #include <sys/wait.h>
26 #include "tst_test.h"
27 #include "common.h"
28
29 static volatile int *run_child;
30
31 static char *str_numchildren;
32 static char *str_writesize;
33 static char *str_filesize;
34 static char *str_offset;
35
36 static int numchildren = 16;
37 static long long writesize = 1024;
38 static long long filesize = 100 * 1024 * 1024;
39 static long long offset = 0;
40 static long long alignment;
41
dio_sparse(int fd,int align,long long fs,int ws,long long off)42 static void dio_sparse(int fd, int align, long long fs, int ws, long long off)
43 {
44 void *bufptr = NULL;
45 long long i;
46 int w;
47
48 bufptr = SAFE_MEMALIGN(align, ws);
49
50 memset(bufptr, 0, ws);
51 SAFE_LSEEK(fd, off, SEEK_SET);
52
53 for (i = off; i < fs;) {
54 if (!tst_remaining_runtime()) {
55 tst_res(TINFO, "Test runtime is over, exiting");
56 return;
57 }
58 w = SAFE_WRITE(SAFE_WRITE_ANY, fd, bufptr, ws);
59 i += w;
60 }
61 }
62
setup(void)63 static void setup(void)
64 {
65 struct stat sb;
66
67 if (tst_parse_int(str_numchildren, &numchildren, 1, INT_MAX))
68 tst_brk(TBROK, "Invalid number of children '%s'", str_numchildren);
69
70 if (tst_parse_filesize(str_writesize, &writesize, 1, LLONG_MAX))
71 tst_brk(TBROK, "Invalid write blocks size '%s'", str_writesize);
72
73 if (tst_parse_filesize(str_filesize, &filesize, 1, LLONG_MAX))
74 tst_brk(TBROK, "Invalid file size '%s'", str_filesize);
75
76 if (tst_parse_filesize(str_offset, &offset, 0, LLONG_MAX))
77 tst_brk(TBROK, "Invalid file offset '%s'", str_offset);
78
79 SAFE_STAT(".", &sb);
80 alignment = sb.st_blksize;
81
82 run_child = SAFE_MMAP(NULL, sizeof(int), PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, -1, 0);
83
84 tst_res(TINFO, "Dirtying free blocks");
85 dirty_freeblocks(100 * 1024 * 1024);
86 }
87
cleanup(void)88 static void cleanup(void)
89 {
90 if (run_child) {
91 *run_child = 0;
92 SAFE_MUNMAP((void *)run_child, sizeof(int));
93 }
94 }
95
run(void)96 static void run(void)
97 {
98 char *filename = "dio_sparse";
99 int fd;
100 int i;
101
102 fd = SAFE_OPEN(filename, O_DIRECT | O_WRONLY | O_CREAT, 0666);
103 SAFE_FTRUNCATE(fd, filesize);
104
105 *run_child = 1;
106
107 for (i = 0; i < numchildren; i++) {
108 if (!SAFE_FORK()) {
109 io_read(filename, filesize, run_child);
110 return;
111 }
112 }
113
114 dio_sparse(fd, alignment, filesize, writesize, offset);
115 *run_child = 0;
116
117 if (!tst_validate_children(numchildren))
118 tst_res(TPASS, "All bytes read were zeroed");
119 }
120
121 static struct tst_test test = {
122 .test_all = run,
123 .setup = setup,
124 .cleanup = cleanup,
125 .needs_tmpdir = 1,
126 .forks_child = 1,
127 .options = (struct tst_option[]) {
128 {"n:", &str_numchildren, "Number of threads (default 16)"},
129 {"w:", &str_writesize, "Size of writing blocks (default 1K)"},
130 {"s:", &str_filesize, "Size of file (default 100M)"},
131 {"o:", &str_offset, "File offset (default 0)"},
132 {}
133 },
134 .skip_filesystems = (const char *[]) {
135 "tmpfs",
136 NULL
137 },
138 .max_runtime = 1800,
139 };
140