udmabuf.c

  1// SPDX-License-Identifier: GPL-2.0
  2#define _GNU_SOURCE
  3#define __EXPORTED_HEADERS__
  4
  5#include <stdio.h>
  6#include <stdlib.h>
  7#include <unistd.h>
  8#include <string.h>
  9#include <errno.h>
 10#include <fcntl.h>
 11#include <malloc.h>
 12#include <stdbool.h>
 13
 14#include <sys/ioctl.h>
 15#include <sys/syscall.h>
 16#include <sys/mman.h>
 17#include <linux/memfd.h>
 18#include <linux/udmabuf.h>
 19#include "kselftest.h"
 20
 21#define TEST_PREFIX	"drivers/dma-buf/udmabuf"
 22#define NUM_PAGES       4
 23#define NUM_ENTRIES     4
 24#define MEMFD_SIZE      1024 /* in pages */
 25
 26static unsigned int page_size;
 27
 28static int create_memfd_with_seals(off64_t size, bool hpage)
 29{
 30	int memfd, ret;
 31	unsigned int flags = MFD_ALLOW_SEALING;
 32
 33	if (hpage)
 34		flags |= MFD_HUGETLB;
 35
 36	memfd = memfd_create("udmabuf-test", flags);
 37	if (memfd < 0) {
 38		ksft_print_msg("%s: [skip,no-memfd]\n", TEST_PREFIX);
 39		exit(KSFT_SKIP);
 40	}
 41
 42	ret = fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK);
 43	if (ret < 0) {
 44		ksft_print_msg("%s: [skip,fcntl-add-seals]\n", TEST_PREFIX);
 45		exit(KSFT_SKIP);
 46	}
 47
 48	ret = ftruncate(memfd, size);
 49	if (ret == -1) {
 50		ksft_print_msg("%s: [FAIL,memfd-truncate]\n", TEST_PREFIX);
 51		exit(KSFT_FAIL);
 52	}
 53
 54	return memfd;
 55}
 56
 57static int create_udmabuf_list(int devfd, int memfd, off64_t memfd_size)
 58{
 59	struct udmabuf_create_list *list;
 60	int ubuf_fd, i;
 61
 62	list = malloc(sizeof(struct udmabuf_create_list) +
 63		      sizeof(struct udmabuf_create_item) * NUM_ENTRIES);
 64	if (!list) {
 65		ksft_print_msg("%s: [FAIL, udmabuf-malloc]\n", TEST_PREFIX);
 66		exit(KSFT_FAIL);
 67	}
 68
 69	for (i = 0; i < NUM_ENTRIES; i++) {
 70		list->list[i].memfd  = memfd;
 71		list->list[i].offset = i * (memfd_size / NUM_ENTRIES);
 72		list->list[i].size   = getpagesize() * NUM_PAGES;
 73	}
 74
 75	list->count = NUM_ENTRIES;
 76	list->flags = UDMABUF_FLAGS_CLOEXEC;
 77	ubuf_fd = ioctl(devfd, UDMABUF_CREATE_LIST, list);
 78	free(list);
 79	if (ubuf_fd < 0) {
 80		ksft_print_msg("%s: [FAIL, udmabuf-create]\n", TEST_PREFIX);
 81		exit(KSFT_FAIL);
 82	}
 83
 84	return ubuf_fd;
 85}
 86
 87static void write_to_memfd(void *addr, off64_t size, char chr)
 88{
 89	int i;
 90
 91	for (i = 0; i < size / page_size; i++) {
 92		*((char *)addr + (i * page_size)) = chr;
 93	}
 94}
 95
 96static void *mmap_fd(int fd, off64_t size)
 97{
 98	void *addr;
 99
100	addr = mmap(NULL, size, PROT_READ|PROT_WRITE, MAP_SHARED, fd, 0);
101	if (addr == MAP_FAILED) {
102		ksft_print_msg("%s: ubuf_fd mmap fail\n", TEST_PREFIX);
103		exit(KSFT_FAIL);
104	}
105
106	return addr;
107}
108
109static int compare_chunks(void *addr1, void *addr2, off64_t memfd_size)
110{
111	off64_t off;
112	int i = 0, j, k = 0, ret = 0;
113	char char1, char2;
114
115	while (i < NUM_ENTRIES) {
116		off = i * (memfd_size / NUM_ENTRIES);
117		for (j = 0; j < NUM_PAGES; j++, k++) {
118			char1 = *((char *)addr1 + off + (j * getpagesize()));
119			char2 = *((char *)addr2 + (k * getpagesize()));
120			if (char1 != char2) {
121				ret = -1;
122				goto err;
123			}
124		}
125		i++;
126	}
127err:
128	munmap(addr1, memfd_size);
129	munmap(addr2, NUM_ENTRIES * NUM_PAGES * getpagesize());
130	return ret;
131}
132
133int main(int argc, char *argv[])
134{
135	struct udmabuf_create create;
136	int devfd, memfd, buf, ret;
137	off64_t size;
138	void *addr1, *addr2;
139
140	ksft_print_header();
141	ksft_set_plan(7);
142
143	devfd = open("/dev/udmabuf", O_RDWR);
144	if (devfd < 0) {
145		ksft_print_msg(
146			"%s: [skip,no-udmabuf: Unable to access DMA buffer device file]\n",
147			TEST_PREFIX);
148		exit(KSFT_SKIP);
149	}
150
151	memfd = memfd_create("udmabuf-test", MFD_ALLOW_SEALING);
152	if (memfd < 0) {
153		ksft_print_msg("%s: [skip,no-memfd]\n", TEST_PREFIX);
154		exit(KSFT_SKIP);
155	}
156
157	ret = fcntl(memfd, F_ADD_SEALS, F_SEAL_SHRINK);
158	if (ret < 0) {
159		ksft_print_msg("%s: [skip,fcntl-add-seals]\n", TEST_PREFIX);
160		exit(KSFT_SKIP);
161	}
162
163	size = getpagesize() * NUM_PAGES;
164	ret = ftruncate(memfd, size);
165	if (ret == -1) {
166		ksft_print_msg("%s: [FAIL,memfd-truncate]\n", TEST_PREFIX);
167		exit(KSFT_FAIL);
168	}
169
170	memset(&create, 0, sizeof(create));
171
172	/* should fail (offset not page aligned) */
173	create.memfd  = memfd;
174	create.offset = getpagesize()/2;
175	create.size   = getpagesize();
176	buf = ioctl(devfd, UDMABUF_CREATE, &create);
177	if (buf >= 0)
178		ksft_test_result_fail("%s: [FAIL,test-1]\n", TEST_PREFIX);
179	else
180		ksft_test_result_pass("%s: [PASS,test-1]\n", TEST_PREFIX);
181
182	/* should fail (size not multiple of page) */
183	create.memfd  = memfd;
184	create.offset = 0;
185	create.size   = getpagesize()/2;
186	buf = ioctl(devfd, UDMABUF_CREATE, &create);
187	if (buf >= 0)
188		ksft_test_result_fail("%s: [FAIL,test-2]\n", TEST_PREFIX);
189	else
190		ksft_test_result_pass("%s: [PASS,test-2]\n", TEST_PREFIX);
191
192	/* should fail (not memfd) */
193	create.memfd  = 0; /* stdin */
194	create.offset = 0;
195	create.size   = size;
196	buf = ioctl(devfd, UDMABUF_CREATE, &create);
197	if (buf >= 0)
198		ksft_test_result_fail("%s: [FAIL,test-3]\n", TEST_PREFIX);
199	else
200		ksft_test_result_pass("%s: [PASS,test-3]\n", TEST_PREFIX);
201
202	/* should work */
203	page_size = getpagesize();
204	addr1 = mmap_fd(memfd, size);
205	write_to_memfd(addr1, size, 'a');
206	create.memfd  = memfd;
207	create.offset = 0;
208	create.size   = size;
209	buf = ioctl(devfd, UDMABUF_CREATE, &create);
210	if (buf < 0)
211		ksft_test_result_fail("%s: [FAIL,test-4]\n", TEST_PREFIX);
212	else
213		ksft_test_result_pass("%s: [PASS,test-4]\n", TEST_PREFIX);
214
215	munmap(addr1, size);
216	close(buf);
217	close(memfd);
218
219	/* should work (migration of 4k size pages)*/
220	size = MEMFD_SIZE * page_size;
221	memfd = create_memfd_with_seals(size, false);
222	addr1 = mmap_fd(memfd, size);
223	write_to_memfd(addr1, size, 'a');
224	buf = create_udmabuf_list(devfd, memfd, size);
225	addr2 = mmap_fd(buf, NUM_PAGES * NUM_ENTRIES * getpagesize());
226	write_to_memfd(addr1, size, 'b');
227	ret = compare_chunks(addr1, addr2, size);
228	if (ret < 0)
229		ksft_test_result_fail("%s: [FAIL,test-5]\n", TEST_PREFIX);
230	else
231		ksft_test_result_pass("%s: [PASS,test-5]\n", TEST_PREFIX);
232
233	close(buf);
234	close(memfd);
235
236	/* should work (migration of 2MB size huge pages)*/
237	page_size = getpagesize() * 512; /* 2 MB */
238	size = MEMFD_SIZE * page_size;
239	memfd = create_memfd_with_seals(size, true);
240	addr1 = mmap_fd(memfd, size);
241	write_to_memfd(addr1, size, 'a');
242	buf = create_udmabuf_list(devfd, memfd, size);
243	addr2 = mmap_fd(buf, NUM_PAGES * NUM_ENTRIES * getpagesize());
244	write_to_memfd(addr1, size, 'b');
245	ret = compare_chunks(addr1, addr2, size);
246	if (ret < 0)
247		ksft_test_result_fail("%s: [FAIL,test-6]\n", TEST_PREFIX);
248	else
249		ksft_test_result_pass("%s: [PASS,test-6]\n", TEST_PREFIX);
250
251	close(buf);
252	close(memfd);
253
254	/* same test as above but we pin first before writing to memfd */
255	page_size = getpagesize() * 512; /* 2 MB */
256	size = MEMFD_SIZE * page_size;
257	memfd = create_memfd_with_seals(size, true);
258	buf = create_udmabuf_list(devfd, memfd, size);
259	addr2 = mmap_fd(buf, NUM_PAGES * NUM_ENTRIES * getpagesize());
260	addr1 = mmap_fd(memfd, size);
261	write_to_memfd(addr1, size, 'a');
262	write_to_memfd(addr1, size, 'b');
263	ret = compare_chunks(addr1, addr2, size);
264	if (ret < 0)
265		ksft_test_result_fail("%s: [FAIL,test-7]\n", TEST_PREFIX);
266	else
267		ksft_test_result_pass("%s: [PASS,test-7]\n", TEST_PREFIX);
268
269	close(buf);
270	close(memfd);
271	close(devfd);
272
273	ksft_print_msg("%s: ok\n", TEST_PREFIX);
274	ksft_print_cnts();
275
276	return 0;
277}