1 /* Copyright (C) 2019 The Android Open Source Project
2  *
3  * Licensed under the Apache License, Version 2.0 (the "License");
4  * you may not use this file except in compliance with the License.
5  * You may obtain a copy of the License at
6  *
7  *      http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software
10  * distributed under the License is distributed on an "AS IS" BASIS,
11  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12  * See the License for the specific language governing permissions and
13  * limitations under the License.
14  */
15 
16 #include <gtest/gtest.h>
17 #include <inttypes.h>
18 #include <linux/dma-buf.h>
19 #include <poll.h>
20 #include <string.h>
21 #include <sys/mman.h>
22 #include <sys/types.h>
23 #include <unistd.h>
24 
25 #include <fstream>
26 #include <string>
27 #include <unordered_map>
28 #include <vector>
29 
30 #include <android-base/file.h>
31 #include <android-base/logging.h>
32 #include <android-base/stringprintf.h>
33 #include <android-base/unique_fd.h>
34 #include <ion/ion.h>
35 
36 #include <dmabufinfo/dmabufinfo.h>
37 
38 using namespace ::android::dmabufinfo;
39 using namespace ::android::base;
40 
41 #define MAX_HEAP_NAME 32
42 #define ION_HEAP_ANY_MASK (0x7fffffff)
43 
44 struct ion_heap_data {
45     char name[MAX_HEAP_NAME];
46     __u32 type;
47     __u32 heap_id;
48     __u32 reserved0;
49     __u32 reserved1;
50     __u32 reserved2;
51 };
52 
53 #ifndef DMA_BUF_SET_NAME
54 #define DMA_BUF_SET_NAME _IOW(DMA_BUF_BASE, 5, const char*)
55 #endif
56 
57 class fd_sharer {
58   public:
59     fd_sharer();
~fd_sharer()60     ~fd_sharer() { kill(); }
61 
ok() const62     bool ok() const { return child_pid > 0; }
63     bool sendfd(int fd);
64     bool kill();
pid() const65     pid_t pid() const { return child_pid; }
66 
67   private:
68     unique_fd parent_fd, child_fd;
69     pid_t child_pid;
70 
71     void run();
72 };
73 
fd_sharer()74 fd_sharer::fd_sharer() : parent_fd{}, child_fd{}, child_pid{-1} {
75     bool sp_ok = android::base::Socketpair(SOCK_STREAM, &parent_fd, &child_fd);
76     if (!sp_ok) return;
77 
78     child_pid = fork();
79     if (child_pid < 0) return;
80 
81     if (child_pid == 0) run();
82 }
83 
kill()84 bool fd_sharer::kill() {
85     int err = ::kill(child_pid, SIGKILL);
86     if (err < 0) return false;
87 
88     return ::waitpid(child_pid, nullptr, 0) == child_pid;
89 }
90 
run()91 void fd_sharer::run() {
92     while (true) {
93         int fd;
94         char unused = 0;
95 
96         iovec iov{};
97         iov.iov_base = &unused;
98         iov.iov_len = sizeof(unused);
99 
100         msghdr msg{};
101         msg.msg_iov = &iov;
102         msg.msg_iovlen = 1;
103 
104         char cmsg_buf[CMSG_SPACE(sizeof(fd))];
105         msg.msg_control = cmsg_buf;
106         msg.msg_controllen = sizeof(cmsg_buf);
107 
108         cmsghdr* cmsg = CMSG_FIRSTHDR(&msg);
109         cmsg->cmsg_level = SOL_SOCKET;
110         cmsg->cmsg_type = SCM_RIGHTS;
111         cmsg->cmsg_len = CMSG_LEN(sizeof(fd));
112 
113         ssize_t s = TEMP_FAILURE_RETRY(recvmsg(child_fd, &msg, 0));
114         if (s == -1) break;
115 
116         s = TEMP_FAILURE_RETRY(write(child_fd, &unused, sizeof(unused)));
117         if (s == -1) break;
118     }
119 }
120 
sendfd(int fd)121 bool fd_sharer::sendfd(int fd) {
122     char unused = 0;
123 
124     iovec iov{};
125     iov.iov_base = &unused;
126     iov.iov_len = sizeof(unused);
127 
128     msghdr msg{};
129     msg.msg_iov = &iov;
130     msg.msg_iovlen = 1;
131 
132     char cmsg_buf[CMSG_SPACE(sizeof(fd))];
133     msg.msg_control = cmsg_buf;
134     msg.msg_controllen = sizeof(cmsg_buf);
135 
136     cmsghdr* cmsg = CMSG_FIRSTHDR(&msg);
137     cmsg->cmsg_level = SOL_SOCKET;
138     cmsg->cmsg_type = SCM_RIGHTS;
139     cmsg->cmsg_len = CMSG_LEN(sizeof(fd));
140 
141     int* fd_buf = reinterpret_cast<int*>(CMSG_DATA(cmsg));
142     *fd_buf = fd;
143 
144     ssize_t s = TEMP_FAILURE_RETRY(sendmsg(parent_fd, &msg, 0));
145     if (s == -1) return false;
146 
147     // The target process installs the fd into its fd table during recvmsg().
148     // So if we return now, there's a brief window between sendfd() finishing
149     // and libmemoryinfo actually seeing that the buffer has been shared.  This
150     // window is just large enough to break tests.
151     //
152     // To work around this, wait for the target process to respond with a dummy
153     // byte, with a timeout of 1 s.
154     pollfd p{};
155     p.fd = parent_fd;
156     p.events = POLL_IN;
157     int ready = poll(&p, 1, 1000);
158     if (ready != 1) return false;
159 
160     s = TEMP_FAILURE_RETRY(read(parent_fd, &unused, sizeof(unused)));
161     if (s == -1) return false;
162 
163     return true;
164 }
165 
166 #define EXPECT_ONE_BUF_EQ(_bufptr, _name, _fdrefs, _maprefs, _expname, _count, _size) \
167     do {                                                                              \
168         EXPECT_EQ(_bufptr->name(), _name);                                            \
169         EXPECT_EQ(_bufptr->fdrefs().size(), _fdrefs);                                 \
170         EXPECT_EQ(_bufptr->maprefs().size(), _maprefs);                               \
171         EXPECT_EQ(_bufptr->exporter(), _expname);                                     \
172         EXPECT_EQ(_bufptr->count(), _count);                                          \
173         EXPECT_EQ(_bufptr->size(), _size);                                            \
174     } while (0)
175 
176 #define EXPECT_PID_IN_FDREFS(_bufptr, _pid, _expect)                         \
177     do {                                                                     \
178         const std::unordered_map<pid_t, int>& _fdrefs = _bufptr->fdrefs();   \
179         auto _ref = _fdrefs.find(_pid);                                      \
180         EXPECT_EQ((_ref != _fdrefs.end()), _expect);                         \
181     } while (0)
182 
183 #define EXPECT_PID_IN_MAPREFS(_bufptr, _pid, _expect)                        \
184     do {                                                                     \
185         const std::unordered_map<pid_t, int>& _maprefs = _bufptr->maprefs(); \
186         auto _ref = _maprefs.find(_pid);                                     \
187         EXPECT_EQ((_ref != _maprefs.end()), _expect);                        \
188     } while (0)
189 
TEST(DmaBufInfoParser,TestReadDmaBufInfo)190 TEST(DmaBufInfoParser, TestReadDmaBufInfo) {
191     std::string bufinfo = R"bufinfo(00045056    00000002    00000007    00000002    ion 00022069
192 	Attached Devices:
193 Total 0 devices attached
194 01048576    00000002    00000007    00000001    ion 00019834    CAMERA
195 	Attached Devices:
196 	soc:qcom,cam_smmu:msm_cam_smmu_icp
197 Total 1 devices attached)bufinfo";
198 
199     TemporaryFile tf;
200     ASSERT_TRUE(tf.fd != -1);
201     ASSERT_TRUE(::android::base::WriteStringToFd(bufinfo, tf.fd));
202     std::string path = std::string(tf.path);
203 
204     std::vector<DmaBuffer> dmabufs;
205     EXPECT_TRUE(ReadDmaBufInfo(&dmabufs, path));
206 
207     EXPECT_EQ(dmabufs.size(), 2UL);
208 
209     EXPECT_EQ(dmabufs[0].size(), 45056UL);
210     EXPECT_EQ(dmabufs[0].inode(), 22069UL);
211     EXPECT_EQ(dmabufs[0].count(), 2UL);
212     EXPECT_EQ(dmabufs[0].exporter(), "ion");
213     EXPECT_TRUE(dmabufs[0].name().empty());
214     EXPECT_EQ(dmabufs[0].total_refs(), 0ULL);
215     EXPECT_TRUE(dmabufs[0].fdrefs().empty());
216     EXPECT_TRUE(dmabufs[0].maprefs().empty());
217 
218     EXPECT_EQ(dmabufs[1].size(), 1048576UL);
219     EXPECT_EQ(dmabufs[1].inode(), 19834UL);
220     EXPECT_EQ(dmabufs[1].count(), 1UL);
221     EXPECT_EQ(dmabufs[1].exporter(), "ion");
222     EXPECT_FALSE(dmabufs[1].name().empty());
223     EXPECT_EQ(dmabufs[1].name(), "CAMERA");
224     EXPECT_EQ(dmabufs[1].total_refs(), 0ULL);
225     EXPECT_TRUE(dmabufs[1].fdrefs().empty());
226     EXPECT_TRUE(dmabufs[1].maprefs().empty());
227 }
228 
229 class DmaBufTester : public ::testing::Test {
230   public:
DmaBufTester()231     DmaBufTester() : ion_fd(ion_open()), ion_heap_mask(get_ion_heap_mask()) {}
232 
~DmaBufTester()233     ~DmaBufTester() {
234         if (ion_fd >= 0) {
235             ion_close(ion_fd);
236         }
237     }
238 
is_valid()239     bool is_valid() { return (ion_fd >= 0 && ion_heap_mask > 0); }
240 
allocate(uint64_t size,const std::string & name)241     unique_fd allocate(uint64_t size, const std::string& name) {
242         int fd;
243         int err = ion_alloc_fd(ion_fd, size, 0, ion_heap_mask, 0, &fd);
244         if (err < 0) {
245             printf("Failed ion_alloc_fd, return value: %d\n", err);
246             return unique_fd{};
247         }
248 
249         if (!name.empty()) {
250             if (ioctl(fd, DMA_BUF_SET_NAME, name.c_str()) == -1) {
251                 printf("Failed ioctl(DMA_BUF_SET_NAME): %s\n", strerror(errno));
252                 close(fd);
253                 return unique_fd{};
254             }
255         }
256 
257         return unique_fd{fd};
258     }
259 
readAndCheckDmaBuffer(std::vector<DmaBuffer> * dmabufs,pid_t pid,const std::string name,size_t fdrefs_size,size_t maprefs_size,const std::string exporter,size_t refcount,uint64_t buf_size,bool expectFdrefs,bool expectMapRefs)260     void readAndCheckDmaBuffer(std::vector<DmaBuffer>* dmabufs, pid_t pid, const std::string name,
261                                size_t fdrefs_size, size_t maprefs_size, const std::string exporter,
262                                size_t refcount, uint64_t buf_size, bool expectFdrefs,
263                                bool expectMapRefs) {
264         EXPECT_TRUE(ReadDmaBufInfo(pid, dmabufs));
265         EXPECT_EQ(dmabufs->size(), 1UL);
266         EXPECT_ONE_BUF_EQ(dmabufs->begin(), name, fdrefs_size, maprefs_size, exporter, refcount,
267                           buf_size);
268         // Make sure the buffer has the right pid too.
269         EXPECT_PID_IN_FDREFS(dmabufs->begin(), pid, expectFdrefs);
270         EXPECT_PID_IN_MAPREFS(dmabufs->begin(), pid, expectMapRefs);
271     }
272 
checkPidRef(DmaBuffer & dmabuf,pid_t pid,int expectFdrefs)273     bool checkPidRef(DmaBuffer& dmabuf, pid_t pid, int expectFdrefs) {
274         int fdrefs = dmabuf.fdrefs().find(pid)->second;
275         return fdrefs == expectFdrefs;
276     }
277 
278   private:
get_ion_heap_mask()279     int get_ion_heap_mask() {
280         if (ion_fd < 0) {
281             return 0;
282         }
283 
284         if (ion_is_legacy(ion_fd)) {
285             // Since ION is still in staging, we've seen that the heap mask ids are also
286             // changed across kernels for some reason. So, here we basically ask for a buffer
287             // from _any_ heap.
288             return ION_HEAP_ANY_MASK;
289         }
290 
291         int cnt;
292         int err = ion_query_heap_cnt(ion_fd, &cnt);
293         if (err < 0) {
294             return err;
295         }
296 
297         std::vector<ion_heap_data> heaps;
298         heaps.resize(cnt);
299         err = ion_query_get_heaps(ion_fd, cnt, &heaps[0]);
300         if (err < 0) {
301             return err;
302         }
303 
304         unsigned int ret = 0;
305         for (auto& it : heaps) {
306             if (!strcmp(it.name, "ion_system_heap")) {
307                 ret |= (1 << it.heap_id);
308             }
309         }
310 
311         return ret;
312     }
313 
314     int ion_fd;
315     const int ion_heap_mask;
316 };
317 
TEST_F(DmaBufTester,TestFdRef)318 TEST_F(DmaBufTester, TestFdRef) {
319     // Test if a dma buffer is found while the corresponding file descriptor
320     // is open
321     ASSERT_TRUE(is_valid());
322     pid_t pid = getpid();
323     std::vector<DmaBuffer> dmabufs;
324     {
325         // Allocate one buffer and make sure the library can see it
326         unique_fd buf = allocate(4096, "dmabuftester-4k");
327         ASSERT_GT(buf, 0) << "Allocated buffer is invalid";
328         ASSERT_TRUE(ReadDmaBufInfo(pid, &dmabufs));
329 
330         EXPECT_EQ(dmabufs.size(), 1UL);
331         EXPECT_ONE_BUF_EQ(dmabufs.begin(), "dmabuftester-4k", 1UL, 0UL, "ion", 1UL, 4096ULL);
332 
333         // Make sure the buffer has the right pid too.
334         EXPECT_PID_IN_FDREFS(dmabufs.begin(), pid, true);
335     }
336 
337     // Now make sure the buffer has disappeared
338     ASSERT_TRUE(ReadDmaBufInfo(pid, &dmabufs));
339     EXPECT_TRUE(dmabufs.empty());
340 }
341 
TEST_F(DmaBufTester,TestMapRef)342 TEST_F(DmaBufTester, TestMapRef) {
343     // Test to make sure we can find a buffer if the fd is closed but the buffer
344     // is mapped
345     ASSERT_TRUE(is_valid());
346     pid_t pid = getpid();
347     std::vector<DmaBuffer> dmabufs;
348     {
349         // Allocate one buffer and make sure the library can see it
350         unique_fd buf = allocate(4096, "dmabuftester-4k");
351         ASSERT_GT(buf, 0) << "Allocated buffer is invalid";
352         auto ptr = mmap(0, 4096, PROT_READ, MAP_SHARED, buf, 0);
353         ASSERT_NE(ptr, MAP_FAILED);
354         ASSERT_TRUE(ReadDmaBufInfo(pid, &dmabufs));
355 
356         EXPECT_EQ(dmabufs.size(), 1UL);
357         EXPECT_ONE_BUF_EQ(dmabufs.begin(), "dmabuftester-4k", 1UL, 1UL, "ion", 2UL, 4096ULL);
358 
359         // Make sure the buffer has the right pid too.
360         EXPECT_PID_IN_FDREFS(dmabufs.begin(), pid, true);
361         EXPECT_PID_IN_MAPREFS(dmabufs.begin(), pid, true);
362 
363         // close the file descriptor and re-read the stats
364         buf.reset(-1);
365         ASSERT_TRUE(ReadDmaBufInfo(pid, &dmabufs));
366 
367         EXPECT_EQ(dmabufs.size(), 1UL);
368         EXPECT_ONE_BUF_EQ(dmabufs.begin(), "<unknown>", 0UL, 1UL, "<unknown>", 0UL, 4096ULL);
369 
370         EXPECT_PID_IN_FDREFS(dmabufs.begin(), pid, false);
371         EXPECT_PID_IN_MAPREFS(dmabufs.begin(), pid, true);
372 
373         // unmap the bufer and lose all references
374         munmap(ptr, 4096);
375     }
376 
377     // Now make sure the buffer has disappeared
378     ASSERT_TRUE(ReadDmaBufInfo(pid, &dmabufs));
379     EXPECT_TRUE(dmabufs.empty());
380 }
381 
TEST_F(DmaBufTester,TestSharedfd)382 TEST_F(DmaBufTester, TestSharedfd) {
383     // Each time a shared buffer is received over a socket, the remote process
384     // will take an extra reference on it.
385 
386     ASSERT_TRUE(is_valid());
387 
388     pid_t pid = getpid();
389     std::vector<DmaBuffer> dmabufs;
390     {
391         fd_sharer sharer{};
392         ASSERT_TRUE(sharer.ok());
393         // Allocate one buffer and make sure the library can see it
394         unique_fd buf = allocate(4096, "dmabuftester-4k");
395         ASSERT_GT(buf, 0) << "Allocated buffer is invalid";
396         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 1UL, 4096ULL, true,
397                               false);
398 
399         ASSERT_TRUE(sharer.sendfd(buf));
400         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 2UL, 4096ULL, true,
401                               false);
402         EXPECT_TRUE(checkPidRef(dmabufs[0], pid, 1));
403         readAndCheckDmaBuffer(&dmabufs, sharer.pid(), "dmabuftester-4k", 1UL, 0UL, "ion", 2UL,
404                               4096ULL, true, false);
405         EXPECT_TRUE(checkPidRef(dmabufs[0], sharer.pid(), 1));
406 
407         ASSERT_TRUE(sharer.sendfd(buf));
408         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 3UL, 4096ULL, true,
409                               false);
410         EXPECT_TRUE(checkPidRef(dmabufs[0], pid, 1));
411         readAndCheckDmaBuffer(&dmabufs, sharer.pid(), "dmabuftester-4k", 1UL, 0UL, "ion", 3UL,
412                               4096ULL, true, false);
413         EXPECT_TRUE(checkPidRef(dmabufs[0], sharer.pid(), 2));
414 
415         ASSERT_TRUE(sharer.kill());
416         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 1UL, 4096ULL, true,
417                               false);
418     }
419 
420     // Now make sure the buffer has disappeared
421     ASSERT_TRUE(ReadDmaBufInfo(pid, &dmabufs));
422     EXPECT_TRUE(dmabufs.empty());
423 }
424 
TEST_F(DmaBufTester,DupFdTest)425 TEST_F(DmaBufTester, DupFdTest) {
426     // dup()ing an fd will make this process take an extra reference on the
427     // shared buffer.
428 
429     ASSERT_TRUE(is_valid());
430 
431     pid_t pid = getpid();
432     std::vector<DmaBuffer> dmabufs;
433     {
434         // Allocate one buffer and make sure the library can see it
435         unique_fd buf = allocate(4096, "dmabuftester-4k");
436         ASSERT_GT(buf, 0) << "Allocated buffer is invalid";
437         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 1UL, 4096ULL, true,
438                               false);
439 
440         unique_fd buf2{dup(buf)};
441         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 2UL, 4096ULL, true,
442                               false);
443         EXPECT_TRUE(checkPidRef(dmabufs[0], pid, 2));
444 
445         close(buf2.release());
446         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 1UL, 4096ULL, true,
447                               false);
448         EXPECT_TRUE(checkPidRef(dmabufs[0], pid, 1));
449     }
450 
451     // Now make sure the buffer has disappeared
452     ASSERT_TRUE(ReadDmaBufInfo(pid, &dmabufs));
453     EXPECT_TRUE(dmabufs.empty());
454 }
455 
TEST_F(DmaBufTester,ForkTest)456 TEST_F(DmaBufTester, ForkTest) {
457     // fork()ing a child will cause the child to automatically take a reference
458     // on any existing shared buffers.
459     ASSERT_TRUE(is_valid());
460 
461     pid_t pid = getpid();
462     std::vector<DmaBuffer> dmabufs;
463     {
464         // Allocate one buffer and make sure the library can see it
465         unique_fd buf = allocate(4096, "dmabuftester-4k");
466         ASSERT_GT(buf, 0) << "Allocated buffer is invalid";
467         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 1UL, 4096ULL, true,
468                               false);
469         fd_sharer sharer{};
470         ASSERT_TRUE(sharer.ok());
471         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 2UL, 4096ULL, true,
472                               false);
473         readAndCheckDmaBuffer(&dmabufs, sharer.pid(), "dmabuftester-4k", 1UL, 0UL, "ion", 2UL,
474                               4096ULL, true, false);
475         ASSERT_TRUE(sharer.kill());
476         readAndCheckDmaBuffer(&dmabufs, pid, "dmabuftester-4k", 1UL, 0UL, "ion", 1UL, 4096ULL, true,
477                               false);
478     }
479 
480     // Now make sure the buffer has disappeared
481     ASSERT_TRUE(ReadDmaBufInfo(pid, &dmabufs));
482     EXPECT_TRUE(dmabufs.empty());
483 }
484 
main(int argc,char ** argv)485 int main(int argc, char** argv) {
486     ::testing::InitGoogleTest(&argc, argv);
487     ::android::base::InitLogging(argv, android::base::StderrLogger);
488     return RUN_ALL_TESTS();
489 }
490