1 // SPDX-License-Identifier: GPL-2.0
2
3 #define _GNU_SOURCE
4 #include <stdlib.h>
5 #include <stdio.h>
6 #include <string.h>
7
8 #include <linux/magic.h>
9 #include <sys/mman.h>
10 #include <sys/statfs.h>
11 #include <errno.h>
12 #include <stdbool.h>
13
14 #include "../kselftest.h"
15
16 #define PREFIX " ... "
17 #define ERROR_PREFIX " !!! "
18
19 #define MAX_WRITE_READ_CHUNK_SIZE (getpagesize() * 16)
20 #define MAX(a, b) (((a) > (b)) ? (a) : (b))
21
22 enum test_status {
23 TEST_PASSED = 0,
24 TEST_FAILED = 1,
25 TEST_SKIPPED = 2,
26 };
27
status_to_str(enum test_status status)28 static char *status_to_str(enum test_status status)
29 {
30 switch (status) {
31 case TEST_PASSED:
32 return "TEST_PASSED";
33 case TEST_FAILED:
34 return "TEST_FAILED";
35 case TEST_SKIPPED:
36 return "TEST_SKIPPED";
37 default:
38 return "TEST_???";
39 }
40 }
41
setup_filemap(char * filemap,size_t len,size_t wr_chunk_size)42 static int setup_filemap(char *filemap, size_t len, size_t wr_chunk_size)
43 {
44 char iter = 0;
45
46 for (size_t offset = 0; offset < len;
47 offset += wr_chunk_size) {
48 iter++;
49 memset(filemap + offset, iter, wr_chunk_size);
50 }
51
52 return 0;
53 }
54
verify_chunk(char * buf,size_t len,char val)55 static bool verify_chunk(char *buf, size_t len, char val)
56 {
57 size_t i;
58
59 for (i = 0; i < len; ++i) {
60 if (buf[i] != val) {
61 printf(PREFIX ERROR_PREFIX "check fail: buf[%lu] = %u != %u\n",
62 i, buf[i], val);
63 return false;
64 }
65 }
66
67 return true;
68 }
69
seek_read_hugepage_filemap(int fd,size_t len,size_t wr_chunk_size,off_t offset,size_t expected)70 static bool seek_read_hugepage_filemap(int fd, size_t len, size_t wr_chunk_size,
71 off_t offset, size_t expected)
72 {
73 char buf[MAX_WRITE_READ_CHUNK_SIZE];
74 ssize_t ret_count = 0;
75 ssize_t total_ret_count = 0;
76 char val = offset / wr_chunk_size + offset % wr_chunk_size;
77
78 printf(PREFIX PREFIX "init val=%u with offset=0x%lx\n", val, offset);
79 printf(PREFIX PREFIX "expect to read 0x%lx bytes of data in total\n",
80 expected);
81 if (lseek(fd, offset, SEEK_SET) < 0) {
82 perror(PREFIX ERROR_PREFIX "seek failed");
83 return false;
84 }
85
86 while (offset + total_ret_count < len) {
87 ret_count = read(fd, buf, wr_chunk_size);
88 if (ret_count == 0) {
89 printf(PREFIX PREFIX "read reach end of the file\n");
90 break;
91 } else if (ret_count < 0) {
92 perror(PREFIX ERROR_PREFIX "read failed");
93 break;
94 }
95 ++val;
96 if (!verify_chunk(buf, ret_count, val))
97 return false;
98
99 total_ret_count += ret_count;
100 }
101 printf(PREFIX PREFIX "actually read 0x%lx bytes of data in total\n",
102 total_ret_count);
103
104 return total_ret_count == expected;
105 }
106
read_hugepage_filemap(int fd,size_t len,size_t wr_chunk_size,size_t expected)107 static bool read_hugepage_filemap(int fd, size_t len,
108 size_t wr_chunk_size, size_t expected)
109 {
110 char buf[MAX_WRITE_READ_CHUNK_SIZE];
111 ssize_t ret_count = 0;
112 ssize_t total_ret_count = 0;
113 char val = 0;
114
115 printf(PREFIX PREFIX "expect to read 0x%lx bytes of data in total\n",
116 expected);
117 while (total_ret_count < len) {
118 ret_count = read(fd, buf, wr_chunk_size);
119 if (ret_count == 0) {
120 printf(PREFIX PREFIX "read reach end of the file\n");
121 break;
122 } else if (ret_count < 0) {
123 perror(PREFIX ERROR_PREFIX "read failed");
124 break;
125 }
126 ++val;
127 if (!verify_chunk(buf, ret_count, val))
128 return false;
129
130 total_ret_count += ret_count;
131 }
132 printf(PREFIX PREFIX "actually read 0x%lx bytes of data in total\n",
133 total_ret_count);
134
135 return total_ret_count == expected;
136 }
137
138 static enum test_status
test_hugetlb_read(int fd,size_t len,size_t wr_chunk_size)139 test_hugetlb_read(int fd, size_t len, size_t wr_chunk_size)
140 {
141 enum test_status status = TEST_SKIPPED;
142 char *filemap = NULL;
143
144 if (ftruncate(fd, len) < 0) {
145 perror(PREFIX ERROR_PREFIX "ftruncate failed");
146 return status;
147 }
148
149 filemap = mmap(NULL, len, PROT_READ | PROT_WRITE,
150 MAP_SHARED | MAP_POPULATE, fd, 0);
151 if (filemap == MAP_FAILED) {
152 perror(PREFIX ERROR_PREFIX "mmap for primary mapping failed");
153 goto done;
154 }
155
156 setup_filemap(filemap, len, wr_chunk_size);
157 status = TEST_FAILED;
158
159 if (read_hugepage_filemap(fd, len, wr_chunk_size, len))
160 status = TEST_PASSED;
161
162 munmap(filemap, len);
163 done:
164 if (ftruncate(fd, 0) < 0) {
165 perror(PREFIX ERROR_PREFIX "ftruncate back to 0 failed");
166 status = TEST_FAILED;
167 }
168
169 return status;
170 }
171
172 static enum test_status
test_hugetlb_read_hwpoison(int fd,size_t len,size_t wr_chunk_size,bool skip_hwpoison_page)173 test_hugetlb_read_hwpoison(int fd, size_t len, size_t wr_chunk_size,
174 bool skip_hwpoison_page)
175 {
176 enum test_status status = TEST_SKIPPED;
177 char *filemap = NULL;
178 char *hwp_addr = NULL;
179 const unsigned long pagesize = getpagesize();
180
181 if (ftruncate(fd, len) < 0) {
182 perror(PREFIX ERROR_PREFIX "ftruncate failed");
183 return status;
184 }
185
186 filemap = mmap(NULL, len, PROT_READ | PROT_WRITE,
187 MAP_SHARED | MAP_POPULATE, fd, 0);
188 if (filemap == MAP_FAILED) {
189 perror(PREFIX ERROR_PREFIX "mmap for primary mapping failed");
190 goto done;
191 }
192
193 setup_filemap(filemap, len, wr_chunk_size);
194 status = TEST_FAILED;
195
196 /*
197 * Poisoned hugetlb page layout (assume hugepagesize=2MB):
198 * |<---------------------- 1MB ---------------------->|
199 * |<---- healthy page ---->|<---- HWPOISON page ----->|
200 * |<------------------- (1MB - 8KB) ----------------->|
201 */
202 hwp_addr = filemap + len / 2 + pagesize;
203 if (madvise(hwp_addr, pagesize, MADV_HWPOISON) < 0) {
204 perror(PREFIX ERROR_PREFIX "MADV_HWPOISON failed");
205 goto unmap;
206 }
207
208 if (!skip_hwpoison_page) {
209 /*
210 * Userspace should be able to read (1MB + 1 page) from
211 * the beginning of the HWPOISONed hugepage.
212 */
213 if (read_hugepage_filemap(fd, len, wr_chunk_size,
214 len / 2 + pagesize))
215 status = TEST_PASSED;
216 } else {
217 /*
218 * Userspace should be able to read (1MB - 2 pages) from
219 * HWPOISONed hugepage.
220 */
221 if (seek_read_hugepage_filemap(fd, len, wr_chunk_size,
222 len / 2 + MAX(2 * pagesize, wr_chunk_size),
223 len / 2 - MAX(2 * pagesize, wr_chunk_size)))
224 status = TEST_PASSED;
225 }
226
227 unmap:
228 munmap(filemap, len);
229 done:
230 if (ftruncate(fd, 0) < 0) {
231 perror(PREFIX ERROR_PREFIX "ftruncate back to 0 failed");
232 status = TEST_FAILED;
233 }
234
235 return status;
236 }
237
create_hugetlbfs_file(struct statfs * file_stat)238 static int create_hugetlbfs_file(struct statfs *file_stat)
239 {
240 int fd;
241
242 fd = memfd_create("hugetlb_tmp", MFD_HUGETLB);
243 if (fd < 0) {
244 perror(PREFIX ERROR_PREFIX "could not open hugetlbfs file");
245 return -1;
246 }
247
248 memset(file_stat, 0, sizeof(*file_stat));
249 if (fstatfs(fd, file_stat)) {
250 perror(PREFIX ERROR_PREFIX "fstatfs failed");
251 goto close;
252 }
253 if (file_stat->f_type != HUGETLBFS_MAGIC) {
254 printf(PREFIX ERROR_PREFIX "not hugetlbfs file\n");
255 goto close;
256 }
257
258 return fd;
259 close:
260 close(fd);
261 return -1;
262 }
263
main(void)264 int main(void)
265 {
266 int fd;
267 struct statfs file_stat;
268 enum test_status status;
269 /* Test read() in different granularity. */
270 size_t wr_chunk_sizes[] = {
271 getpagesize() / 2, getpagesize(),
272 getpagesize() * 2, getpagesize() * 4
273 };
274 size_t i;
275
276 for (i = 0; i < ARRAY_SIZE(wr_chunk_sizes); ++i) {
277 printf("Write/read chunk size=0x%lx\n",
278 wr_chunk_sizes[i]);
279
280 fd = create_hugetlbfs_file(&file_stat);
281 if (fd < 0)
282 goto create_failure;
283 printf(PREFIX "HugeTLB read regression test...\n");
284 status = test_hugetlb_read(fd, file_stat.f_bsize,
285 wr_chunk_sizes[i]);
286 printf(PREFIX "HugeTLB read regression test...%s\n",
287 status_to_str(status));
288 close(fd);
289 if (status == TEST_FAILED)
290 return -1;
291
292 fd = create_hugetlbfs_file(&file_stat);
293 if (fd < 0)
294 goto create_failure;
295 printf(PREFIX "HugeTLB read HWPOISON test...\n");
296 status = test_hugetlb_read_hwpoison(fd, file_stat.f_bsize,
297 wr_chunk_sizes[i], false);
298 printf(PREFIX "HugeTLB read HWPOISON test...%s\n",
299 status_to_str(status));
300 close(fd);
301 if (status == TEST_FAILED)
302 return -1;
303
304 fd = create_hugetlbfs_file(&file_stat);
305 if (fd < 0)
306 goto create_failure;
307 printf(PREFIX "HugeTLB seek then read HWPOISON test...\n");
308 status = test_hugetlb_read_hwpoison(fd, file_stat.f_bsize,
309 wr_chunk_sizes[i], true);
310 printf(PREFIX "HugeTLB seek then read HWPOISON test...%s\n",
311 status_to_str(status));
312 close(fd);
313 if (status == TEST_FAILED)
314 return -1;
315 }
316
317 return 0;
318
319 create_failure:
320 printf(ERROR_PREFIX "Abort test: failed to create hugetlbfs file\n");
321 return -1;
322 }
323