These tests verify that the cgroup GPU memory charge is transferred correctly when a dmabuf is passed between processes in two different cgroups and the sender specifies BINDER_FD_FLAG_SENDER_NO_NEED or BINDER_FDA_FLAG_SENDER_NO_NEED in the binder transaction data containing the dmabuf file descriptor.
Signed-off-by: T.J. Mercier tjmercier@google.com
--- v5 changes Tests for both binder_fd_array_object and binder_fd_object.
Return error code instead of struct binder{fs}_ctx.
Use ifdef __ANDROID__ to choose platform-dependent temp path instead of a runtime fallback.
Ensure binderfs_mntpt ends with a trailing '/' character instead of prepending it where used.
v4 changes Skip test if not run as root per Shuah Khan.
Add better logging for abnormal child termination per Shuah Khan. --- .../selftests/drivers/android/binder/Makefile | 8 + .../drivers/android/binder/binder_util.c | 250 +++++++++ .../drivers/android/binder/binder_util.h | 32 ++ .../selftests/drivers/android/binder/config | 4 + .../binder/test_dmabuf_cgroup_transfer.c | 526 ++++++++++++++++++ 5 files changed, 820 insertions(+) create mode 100644 tools/testing/selftests/drivers/android/binder/Makefile create mode 100644 tools/testing/selftests/drivers/android/binder/binder_util.c create mode 100644 tools/testing/selftests/drivers/android/binder/binder_util.h create mode 100644 tools/testing/selftests/drivers/android/binder/config create mode 100644 tools/testing/selftests/drivers/android/binder/test_dmabuf_cgroup_transfer.c
diff --git a/tools/testing/selftests/drivers/android/binder/Makefile b/tools/testing/selftests/drivers/android/binder/Makefile new file mode 100644 index 000000000000..726439d10675 --- /dev/null +++ b/tools/testing/selftests/drivers/android/binder/Makefile @@ -0,0 +1,8 @@ +# SPDX-License-Identifier: GPL-2.0 +CFLAGS += -Wall + +TEST_GEN_PROGS = test_dmabuf_cgroup_transfer + +include ../../../lib.mk + +$(OUTPUT)/test_dmabuf_cgroup_transfer: ../../../cgroup/cgroup_util.c binder_util.c diff --git a/tools/testing/selftests/drivers/android/binder/binder_util.c b/tools/testing/selftests/drivers/android/binder/binder_util.c new file mode 100644 index 000000000000..cdd97cb0bb60 --- /dev/null +++ b/tools/testing/selftests/drivers/android/binder/binder_util.c @@ -0,0 +1,250 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include "binder_util.h" + +#include <errno.h> +#include <fcntl.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/mount.h> + +#include <linux/limits.h> +#include <linux/android/binder.h> +#include <linux/android/binderfs.h> + +static const size_t BINDER_MMAP_SIZE = 64 * 1024; + +static void binderfs_unmount(const char *mountpoint) +{ + if (umount2(mountpoint, MNT_DETACH)) + fprintf(stderr, "Failed to unmount binderfs at %s: %s\n", + mountpoint, strerror(errno)); + else + fprintf(stderr, "Binderfs unmounted: %s\n", mountpoint); + + if (rmdir(mountpoint)) + fprintf(stderr, "Failed to remove binderfs mount %s: %s\n", + mountpoint, strerror(errno)); + else + fprintf(stderr, "Binderfs mountpoint destroyed: %s\n", mountpoint); +} + +int create_binderfs(struct binderfs_ctx *ctx, const char *name) +{ + int fd, ret, saved_errno; + struct binderfs_device device = { 0 }; + + /* + * P_tmpdir is set to "/tmp/" on Android platforms where Binder is most commonly used, but + * this path does not actually exist on Android. For Android we'll try using + * "/data/local/tmp" and P_tmpdir for non-Android platforms. + * + * This mount point should have a trailing '/' character, but mkdtemp requires that the last + * six characters (before the first null terminator) must be "XXXXXX". Manually append an + * additional null character in the string literal to allocate a character array of the + * correct final size, which we will replace with a '/' after successful completion of the + * mkdtemp call. + */ +#ifdef __ANDROID__ + char binderfs_mntpt[] = "/data/local/tmp/binderfs_XXXXXX\0"; +#else + /* P_tmpdir may or may not contain a trailing '/' separator. We always append one here. */ + char binderfs_mntpt[] = P_tmpdir "/binderfs_XXXXXX\0"; +#endif + static const char BINDER_CONTROL_NAME[] = "binder-control"; + char device_path[strlen(binderfs_mntpt) + 1 + strlen(BINDER_CONTROL_NAME) + 1]; + + if (mkdtemp(binderfs_mntpt) == NULL) { + fprintf(stderr, "Failed to create binderfs mountpoint at %s: %s.\n", + binderfs_mntpt, strerror(errno)); + return -1; + } + binderfs_mntpt[strlen(binderfs_mntpt)] = '/'; + fprintf(stderr, "Binderfs mountpoint created at %s\n", binderfs_mntpt); + + if (mount(NULL, binderfs_mntpt, "binder", 0, 0)) { + perror("Could not mount binderfs"); + rmdir(binderfs_mntpt); + return -1; + } + fprintf(stderr, "Binderfs mounted at %s\n", binderfs_mntpt); + + strncpy(device.name, name, sizeof(device.name)); + snprintf(device_path, sizeof(device_path), "%s%s", binderfs_mntpt, BINDER_CONTROL_NAME); + fd = open(device_path, O_RDONLY | O_CLOEXEC); + if (!fd) { + fprintf(stderr, "Failed to open %s device", BINDER_CONTROL_NAME); + binderfs_unmount(binderfs_mntpt); + return -1; + } + + ret = ioctl(fd, BINDER_CTL_ADD, &device); + saved_errno = errno; + close(fd); + errno = saved_errno; + if (ret) { + perror("Failed to allocate new binder device"); + binderfs_unmount(binderfs_mntpt); + return -1; + } + + fprintf(stderr, "Allocated new binder device with major %d, minor %d, and name %s at %s\n", + device.major, device.minor, device.name, binderfs_mntpt); + + ctx->name = strdup(name); + ctx->mountpoint = strdup(binderfs_mntpt); + + return 0; +} + +void destroy_binderfs(struct binderfs_ctx *ctx) +{ + char path[PATH_MAX]; + + snprintf(path, sizeof(path), "%s%s", ctx->mountpoint, ctx->name); + + if (unlink(path)) + fprintf(stderr, "Failed to unlink binder device %s: %s\n", path, strerror(errno)); + else + fprintf(stderr, "Destroyed binder %s at %s\n", ctx->name, ctx->mountpoint); + + binderfs_unmount(ctx->mountpoint); + + free(ctx->name); + free(ctx->mountpoint); +} + +int open_binder(const struct binderfs_ctx *bfs_ctx, struct binder_ctx *ctx) +{ + char path[PATH_MAX]; + + snprintf(path, sizeof(path), "%s%s", bfs_ctx->mountpoint, bfs_ctx->name); + ctx->fd = open(path, O_RDWR | O_NONBLOCK | O_CLOEXEC); + if (ctx->fd < 0) { + fprintf(stderr, "Error opening binder device %s: %s\n", path, strerror(errno)); + return -1; + } + + ctx->memory = mmap(NULL, BINDER_MMAP_SIZE, PROT_READ, MAP_SHARED, ctx->fd, 0); + if (ctx->memory == NULL) { + perror("Error mapping binder memory"); + close(ctx->fd); + ctx->fd = -1; + return -1; + } + + return 0; +} + +void close_binder(struct binder_ctx *ctx) +{ + if (munmap(ctx->memory, BINDER_MMAP_SIZE)) + perror("Failed to unmap binder memory"); + ctx->memory = NULL; + + if (close(ctx->fd)) + perror("Failed to close binder"); + ctx->fd = -1; +} + +int become_binder_context_manager(int binder_fd) +{ + return ioctl(binder_fd, BINDER_SET_CONTEXT_MGR, 0); +} + +int do_binder_write_read(int binder_fd, void *writebuf, binder_size_t writesize, + void *readbuf, binder_size_t readsize) +{ + int err; + struct binder_write_read bwr = { + .write_buffer = (binder_uintptr_t)writebuf, + .write_size = writesize, + .read_buffer = (binder_uintptr_t)readbuf, + .read_size = readsize + }; + + do { + if (ioctl(binder_fd, BINDER_WRITE_READ, &bwr) >= 0) + err = 0; + else + err = -errno; + } while (err == -EINTR); + + if (err < 0) { + perror("BINDER_WRITE_READ"); + return -1; + } + + if (bwr.write_consumed < writesize) { + fprintf(stderr, "Binder did not consume full write buffer %llu %llu\n", + bwr.write_consumed, writesize); + return -1; + } + + return bwr.read_consumed; +} + +static const char *reply_string(int cmd) +{ + switch (cmd) { + case BR_ERROR: + return "BR_ERROR"; + case BR_OK: + return "BR_OK"; + case BR_TRANSACTION_SEC_CTX: + return "BR_TRANSACTION_SEC_CTX"; + case BR_TRANSACTION: + return "BR_TRANSACTION"; + case BR_REPLY: + return "BR_REPLY"; + case BR_ACQUIRE_RESULT: + return "BR_ACQUIRE_RESULT"; + case BR_DEAD_REPLY: + return "BR_DEAD_REPLY"; + case BR_TRANSACTION_COMPLETE: + return "BR_TRANSACTION_COMPLETE"; + case BR_INCREFS: + return "BR_INCREFS"; + case BR_ACQUIRE: + return "BR_ACQUIRE"; + case BR_RELEASE: + return "BR_RELEASE"; + case BR_DECREFS: + return "BR_DECREFS"; + case BR_ATTEMPT_ACQUIRE: + return "BR_ATTEMPT_ACQUIRE"; + case BR_NOOP: + return "BR_NOOP"; + case BR_SPAWN_LOOPER: + return "BR_SPAWN_LOOPER"; + case BR_FINISHED: + return "BR_FINISHED"; + case BR_DEAD_BINDER: + return "BR_DEAD_BINDER"; + case BR_CLEAR_DEATH_NOTIFICATION_DONE: + return "BR_CLEAR_DEATH_NOTIFICATION_DONE"; + case BR_FAILED_REPLY: + return "BR_FAILED_REPLY"; + case BR_FROZEN_REPLY: + return "BR_FROZEN_REPLY"; + case BR_ONEWAY_SPAM_SUSPECT: + return "BR_ONEWAY_SPAM_SUSPECT"; + default: + return "Unknown"; + }; +} + +int expect_binder_reply(int32_t actual, int32_t expected) +{ + if (actual != expected) { + fprintf(stderr, "Expected %s but received %s\n", + reply_string(expected), reply_string(actual)); + return -1; + } + return 0; +} + diff --git a/tools/testing/selftests/drivers/android/binder/binder_util.h b/tools/testing/selftests/drivers/android/binder/binder_util.h new file mode 100644 index 000000000000..adc2b20e8d0a --- /dev/null +++ b/tools/testing/selftests/drivers/android/binder/binder_util.h @@ -0,0 +1,32 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef SELFTEST_BINDER_UTIL_H +#define SELFTEST_BINDER_UTIL_H + +#include <stdint.h> + +#include <linux/android/binder.h> + +struct binderfs_ctx { + char *name; + char *mountpoint; +}; + +struct binder_ctx { + int fd; + void *memory; +}; + +int create_binderfs(struct binderfs_ctx *ctx, const char *name); +void destroy_binderfs(struct binderfs_ctx *ctx); + +int open_binder(const struct binderfs_ctx *bfs_ctx, struct binder_ctx *ctx); +void close_binder(struct binder_ctx *ctx); + +int become_binder_context_manager(int binder_fd); + +int do_binder_write_read(int binder_fd, void *writebuf, binder_size_t writesize, + void *readbuf, binder_size_t readsize); + +int expect_binder_reply(int32_t actual, int32_t expected); +#endif diff --git a/tools/testing/selftests/drivers/android/binder/config b/tools/testing/selftests/drivers/android/binder/config new file mode 100644 index 000000000000..fcc5f8f693b3 --- /dev/null +++ b/tools/testing/selftests/drivers/android/binder/config @@ -0,0 +1,4 @@ +CONFIG_CGROUP_GPU=y +CONFIG_ANDROID=y +CONFIG_ANDROID_BINDERFS=y +CONFIG_ANDROID_BINDER_IPC=y diff --git a/tools/testing/selftests/drivers/android/binder/test_dmabuf_cgroup_transfer.c b/tools/testing/selftests/drivers/android/binder/test_dmabuf_cgroup_transfer.c new file mode 100644 index 000000000000..75ca49d1a2e4 --- /dev/null +++ b/tools/testing/selftests/drivers/android/binder/test_dmabuf_cgroup_transfer.c @@ -0,0 +1,526 @@ +// SPDX-License-Identifier: GPL-2.0 + +/* + * These tests verify that the cgroup GPU memory charge is transferred correctly when a dmabuf is + * passed between processes in two different cgroups and the sender specifies + * BINDER_FD_FLAG_SENDER_NO_NEED or BINDER_FDA_FLAG_SENDER_NO_NEED in the binder transaction data + * containing the dmabuf file descriptor. + * + * The parent test process becomes the binder context manager, then forks a child who initiates a + * transaction with the context manager by specifying a target of 0. The context manager reply + * contains a dmabuf file descriptor (or an array of one file descriptor) which was allocated by the + * parent, but should be charged to the child cgroup after the binder transaction. + */ + +#include <errno.h> +#include <fcntl.h> +#include <stddef.h> +#include <stdint.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.h> +#include <sys/epoll.h> +#include <sys/ioctl.h> +#include <sys/types.h> +#include <sys/wait.h> + +#include "binder_util.h" +#include "../../../cgroup/cgroup_util.h" +#include "../../../kselftest.h" +#include "../../../kselftest_harness.h" + +#include <linux/limits.h> +#include <linux/dma-heap.h> +#include <linux/android/binder.h> + +#define UNUSED(x) ((void)(x)) + +static const unsigned int BINDER_CODE = 8675309; /* Any number will work here */ + +struct cgroup_ctx { + char *root; + char *source; + char *dest; +}; + +void destroy_cgroups(struct __test_metadata *_metadata, struct cgroup_ctx *ctx) +{ + if (ctx->source != NULL) { + TH_LOG("Destroying cgroup: %s", ctx->source); + rmdir(ctx->source); + free(ctx->source); + } + + if (ctx->dest != NULL) { + TH_LOG("Destroying cgroup: %s", ctx->dest); + rmdir(ctx->dest); + free(ctx->dest); + } + + free(ctx->root); + ctx->root = ctx->source = ctx->dest = NULL; +} + +struct cgroup_ctx create_cgroups(struct __test_metadata *_metadata) +{ + struct cgroup_ctx ctx = {0}; + char root[PATH_MAX], *tmp; + static const char template[] = "/gpucg_XXXXXX"; + + if (cg_find_unified_root(root, sizeof(root))) { + TH_LOG("Could not find cgroups root"); + return ctx; + } + + if (cg_read_strstr(root, "cgroup.controllers", "gpu")) { + TH_LOG("Could not find GPU controller"); + return ctx; + } + + if (cg_write(root, "cgroup.subtree_control", "+gpu")) { + TH_LOG("Could not enable GPU controller"); + return ctx; + } + + ctx.root = strdup(root); + + snprintf(root, sizeof(root), "%s/%s", ctx.root, template); + tmp = mkdtemp(root); + if (tmp == NULL) { + TH_LOG("%s - Could not create source cgroup", strerror(errno)); + destroy_cgroups(_metadata, &ctx); + return ctx; + } + ctx.source = strdup(tmp); + + snprintf(root, sizeof(root), "%s/%s", ctx.root, template); + tmp = mkdtemp(root); + if (tmp == NULL) { + TH_LOG("%s - Could not create destination cgroup", strerror(errno)); + destroy_cgroups(_metadata, &ctx); + return ctx; + } + ctx.dest = strdup(tmp); + + TH_LOG("Created cgroups: %s %s", ctx.source, ctx.dest); + + return ctx; +} + +int dmabuf_heap_alloc(int fd, size_t len, int *dmabuf_fd) +{ + struct dma_heap_allocation_data data = { + .len = len, + .fd = 0, + .fd_flags = O_RDONLY | O_CLOEXEC, + .heap_flags = 0, + }; + int ret; + + if (!dmabuf_fd) + return -EINVAL; + + ret = ioctl(fd, DMA_HEAP_IOCTL_ALLOC, &data); + if (ret < 0) + return ret; + *dmabuf_fd = (int)data.fd; + return ret; +} + +/* The system heap is known to export dmabufs with support for cgroup tracking */ +int alloc_dmabuf_from_system_heap(struct __test_metadata *_metadata, size_t bytes) +{ + int heap_fd = -1, dmabuf_fd = -1; + static const char * const heap_path = "/dev/dma_heap/system"; + + heap_fd = open(heap_path, O_RDONLY); + if (heap_fd < 0) { + TH_LOG("%s - open %s failed!\n", strerror(errno), heap_path); + return -1; + } + + if (dmabuf_heap_alloc(heap_fd, bytes, &dmabuf_fd)) + TH_LOG("dmabuf allocation failed! - %s", strerror(errno)); + close(heap_fd); + + return dmabuf_fd; +} + +int binder_request_dmabuf(int binder_fd) +{ + int ret; + + /* + * We just send an empty binder_buffer_object to initiate a transaction + * with the context manager, who should respond with a single dmabuf + * inside a binder_fd_array_object or a binder_fd_object. + */ + + struct binder_buffer_object bbo = { + .hdr.type = BINDER_TYPE_PTR, + .flags = 0, + .buffer = 0, + .length = 0, + .parent = 0, /* No parent */ + .parent_offset = 0 /* No parent */ + }; + + binder_size_t offsets[] = {0}; + + struct { + int32_t cmd; + struct binder_transaction_data btd; + } __attribute__((packed)) bc = { + .cmd = BC_TRANSACTION, + .btd = { + .target = { 0 }, + .cookie = 0, + .code = BINDER_CODE, + .flags = TF_ACCEPT_FDS, /* We expect a FD/FDA in the reply */ + .data_size = sizeof(bbo), + .offsets_size = sizeof(offsets), + .data.ptr = { + (binder_uintptr_t)&bbo, + (binder_uintptr_t)offsets + } + }, + }; + + struct { + int32_t reply_noop; + } __attribute__((packed)) br; + + ret = do_binder_write_read(binder_fd, &bc, sizeof(bc), &br, sizeof(br)); + if (ret >= sizeof(br) && expect_binder_reply(br.reply_noop, BR_NOOP)) { + return -1; + } else if (ret < sizeof(br)) { + fprintf(stderr, "Not enough bytes in binder reply %d\n", ret); + return -1; + } + return 0; +} + +int send_dmabuf_reply_fda(int binder_fd, struct binder_transaction_data *tr, int dmabuf_fd) +{ + int ret; + /* + * The trailing 0 is to achieve the necessary alignment for the binder + * buffer_size. + */ + int fdarray[] = { dmabuf_fd, 0 }; + + struct binder_buffer_object bbo = { + .hdr.type = BINDER_TYPE_PTR, + .flags = 0, + .buffer = (binder_uintptr_t)fdarray, + .length = sizeof(fdarray), + .parent = 0, /* No parent */ + .parent_offset = 0 /* No parent */ + }; + + struct binder_fd_array_object bfdao = { + .hdr.type = BINDER_TYPE_FDA, + .flags = BINDER_FDA_FLAG_SENDER_NO_NEED, + .num_fds = 1, + .parent = 0, /* The binder_buffer_object */ + .parent_offset = 0 /* FDs follow immediately */ + }; + + uint64_t sz = sizeof(fdarray); + uint8_t data[sizeof(sz) + sizeof(bbo) + sizeof(bfdao)]; + binder_size_t offsets[] = {sizeof(sz), sizeof(sz)+sizeof(bbo)}; + + memcpy(data, &sz, sizeof(sz)); + memcpy(data + sizeof(sz), &bbo, sizeof(bbo)); + memcpy(data + sizeof(sz) + sizeof(bbo), &bfdao, sizeof(bfdao)); + + struct { + int32_t cmd; + struct binder_transaction_data_sg btd; + } __attribute__((packed)) bc = { + .cmd = BC_REPLY_SG, + .btd.transaction_data = { + .target = { tr->target.handle }, + .cookie = tr->cookie, + .code = BINDER_CODE, + .flags = 0, + .data_size = sizeof(data), + .offsets_size = sizeof(offsets), + .data.ptr = { + (binder_uintptr_t)data, + (binder_uintptr_t)offsets + } + }, + .btd.buffers_size = sizeof(fdarray) + }; + + struct { + int32_t reply_noop; + } __attribute__((packed)) br; + + ret = do_binder_write_read(binder_fd, &bc, sizeof(bc), &br, sizeof(br)); + if (ret >= sizeof(br) && expect_binder_reply(br.reply_noop, BR_NOOP)) { + return -1; + } else if (ret < sizeof(br)) { + fprintf(stderr, "Not enough bytes in binder reply %d\n", ret); + return -1; + } + return 0; +} + +int send_dmabuf_reply_fd(int binder_fd, struct binder_transaction_data *tr, int dmabuf_fd) +{ + int ret; + + struct binder_fd_object bfdo = { + .hdr.type = BINDER_TYPE_FD, + .flags = BINDER_FD_FLAG_SENDER_NO_NEED, + .fd = dmabuf_fd + }; + + binder_size_t offset = 0; + + struct { + int32_t cmd; + struct binder_transaction_data btd; + } __attribute__((packed)) bc = { + .cmd = BC_REPLY, + .btd = { + .target = { tr->target.handle }, + .cookie = tr->cookie, + .code = BINDER_CODE, + .flags = 0, + .data_size = sizeof(bfdo), + .offsets_size = sizeof(offset), + .data.ptr = { + (binder_uintptr_t)&bfdo, + (binder_uintptr_t)&offset + } + } + }; + + struct { + int32_t reply_noop; + } __attribute__((packed)) br; + + ret = do_binder_write_read(binder_fd, &bc, sizeof(bc), &br, sizeof(br)); + if (ret >= sizeof(br) && expect_binder_reply(br.reply_noop, BR_NOOP)) { + return -1; + } else if (ret < sizeof(br)) { + fprintf(stderr, "Not enough bytes in binder reply %d\n", ret); + return -1; + } + return 0; +} + +struct binder_transaction_data *binder_wait_for_transaction(int binder_fd, + uint32_t *readbuf, + size_t readsize) +{ + static const int MAX_EVENTS = 1, EPOLL_WAIT_TIME_MS = 3 * 1000; + struct binder_reply { + int32_t reply0; + int32_t reply1; + struct binder_transaction_data btd; + } *br; + struct binder_transaction_data *ret = NULL; + struct epoll_event events[MAX_EVENTS]; + int epoll_fd, num_events, readcount; + uint32_t bc[] = { BC_ENTER_LOOPER }; + + do_binder_write_read(binder_fd, &bc, sizeof(bc), NULL, 0); + + epoll_fd = epoll_create1(EPOLL_CLOEXEC); + if (epoll_fd == -1) { + perror("epoll_create"); + return NULL; + } + + events[0].events = EPOLLIN; + if (epoll_ctl(epoll_fd, EPOLL_CTL_ADD, binder_fd, &events[0])) { + perror("epoll_ctl add"); + goto err_close; + } + + num_events = epoll_wait(epoll_fd, events, MAX_EVENTS, EPOLL_WAIT_TIME_MS); + if (num_events < 0) { + perror("epoll_wait"); + goto err_ctl; + } else if (num_events == 0) { + fprintf(stderr, "No events\n"); + goto err_ctl; + } + + readcount = do_binder_write_read(binder_fd, NULL, 0, readbuf, readsize); + fprintf(stderr, "Read %d bytes from binder\n", readcount); + + if (readcount < (int)sizeof(struct binder_reply)) { + fprintf(stderr, "read_consumed not large enough\n"); + goto err_ctl; + } + + br = (struct binder_reply *)readbuf; + if (expect_binder_reply(br->reply0, BR_NOOP)) + goto err_ctl; + + if (br->reply1 == BR_TRANSACTION) { + if (br->btd.code == BINDER_CODE) + ret = &br->btd; + else + fprintf(stderr, "Received transaction with unexpected code: %u\n", + br->btd.code); + } else { + expect_binder_reply(br->reply1, BR_TRANSACTION_COMPLETE); + } + +err_ctl: + if (epoll_ctl(epoll_fd, EPOLL_CTL_DEL, binder_fd, NULL)) + perror("epoll_ctl del"); +err_close: + close(epoll_fd); + return ret; +} + +static int child_request_dmabuf_transfer(const char *cgroup, void *arg) +{ + UNUSED(cgroup); + int ret = -1; + uint32_t readbuf[32]; + struct binderfs_ctx bfs_ctx = *(struct binderfs_ctx *)arg; + struct binder_ctx b_ctx; + + fprintf(stderr, "Child PID: %d\n", getpid()); + + if (open_binder(&bfs_ctx, &b_ctx)) { + fprintf(stderr, "Child unable to open binder\n"); + return -1; + } + + if (binder_request_dmabuf(b_ctx.fd)) + goto err; + + /* The child must stay alive until the binder reply is received */ + if (binder_wait_for_transaction(b_ctx.fd, readbuf, sizeof(readbuf)) == NULL) + ret = 0; + + /* + * We don't close the received dmabuf here so that the parent can + * inspect the cgroup gpu memory charges to verify the charge transfer + * completed successfully. + */ +err: + close_binder(&b_ctx); + fprintf(stderr, "Child done\n"); + return ret; +} + +static const char * const GPUMEM_FILENAME = "gpu.memory.current"; +static const size_t ONE_MiB = 1024 * 1024; + +FIXTURE(fix) { + int dmabuf_fd; + struct binderfs_ctx bfs_ctx; + struct binder_ctx b_ctx; + struct cgroup_ctx cg_ctx; + struct binder_transaction_data *tr; + pid_t child_pid; +}; + +FIXTURE_SETUP(fix) +{ + long memsize; + uint32_t readbuf[32]; + struct flat_binder_object *fbo; + struct binder_buffer_object *bbo; + + if (geteuid() != 0) + ksft_exit_skip("Need to be root to mount binderfs\n"); + + if (create_binderfs(&self->bfs_ctx, "testbinder")) + ksft_exit_skip("The Android binderfs filesystem is not available\n"); + + self->cg_ctx = create_cgroups(_metadata); + if (self->cg_ctx.root == NULL) { + destroy_binderfs(&self->bfs_ctx); + ksft_exit_skip("cgroup v2 isn't mounted\n"); + } + + ASSERT_EQ(cg_enter_current(self->cg_ctx.source), 0) { + TH_LOG("Could not move parent to cgroup: %s", self->cg_ctx.source); + } + + self->dmabuf_fd = alloc_dmabuf_from_system_heap(_metadata, ONE_MiB); + ASSERT_GE(self->dmabuf_fd, 0); + TH_LOG("Allocated dmabuf"); + + memsize = cg_read_key_long(self->cg_ctx.source, GPUMEM_FILENAME, "system-heap"); + ASSERT_EQ(memsize, ONE_MiB) { + TH_LOG("GPU memory used after allocation: %ld but it should be %lu", + memsize, (unsigned long)ONE_MiB); + } + + ASSERT_EQ(open_binder(&self->bfs_ctx, &self->b_ctx), 0) { + TH_LOG("Parent unable to open binder"); + } + TH_LOG("Opened binder at %s/%s", self->bfs_ctx.mountpoint, self->bfs_ctx.name); + + ASSERT_EQ(become_binder_context_manager(self->b_ctx.fd), 0) { + TH_LOG("Cannot become context manager: %s", strerror(errno)); + } + + self->child_pid = cg_run_nowait( + self->cg_ctx.dest, child_request_dmabuf_transfer, &self->bfs_ctx); + ASSERT_GT(self->child_pid, 0) { + TH_LOG("Error forking: %s", strerror(errno)); + } + + self->tr = binder_wait_for_transaction(self->b_ctx.fd, readbuf, sizeof(readbuf)); + ASSERT_NE(self->tr, NULL) { + TH_LOG("Error receiving transaction request from child"); + } + fbo = (struct flat_binder_object *)self->tr->data.ptr.buffer; + ASSERT_EQ(fbo->hdr.type, BINDER_TYPE_PTR) { + TH_LOG("Did not receive a buffer object from child"); + } + bbo = (struct binder_buffer_object *)fbo; + ASSERT_EQ(bbo->length, 0) { + TH_LOG("Did not receive an empty buffer object from child"); + } + + TH_LOG("Received transaction from child"); +} + +FIXTURE_TEARDOWN(fix) +{ + close_binder(&self->b_ctx); + close(self->dmabuf_fd); + destroy_cgroups(_metadata, &self->cg_ctx); + destroy_binderfs(&self->bfs_ctx); +} + + +void verify_transfer_success(struct _test_data_fix *self, struct __test_metadata *_metadata) +{ + ASSERT_EQ(cg_read_key_long(self->cg_ctx.dest, GPUMEM_FILENAME, "system-heap"), ONE_MiB) { + TH_LOG("Destination cgroup does not have system-heap charge!"); + } + ASSERT_EQ(cg_read_key_long(self->cg_ctx.source, GPUMEM_FILENAME, "system-heap"), 0) { + TH_LOG("Source cgroup still has system-heap charge!"); + } + TH_LOG("Charge transfer succeeded!"); +} + +TEST_F(fix, individual_fd) +{ + send_dmabuf_reply_fd(self->b_ctx.fd, self->tr, self->dmabuf_fd); + verify_transfer_success(self, _metadata); +} + +TEST_F(fix, fd_array) +{ + send_dmabuf_reply_fda(self->b_ctx.fd, self->tr, self->dmabuf_fd); + verify_transfer_success(self, _metadata); +} + +TEST_HARNESS_MAIN