kselftests: Add dma-heap test

Add very trivial allocation and import test for dma-heaps,
utilizing the vgem driver as a test importer.

A good chunk of this code taken from:
tools/testing/selftests/android/ion/ionmap_test.c
Originally by Laura Abbott <[e-mail]>

Cc: Benjamin Gaignard <[e-mail]>
Cc: Sumit Semwal <[e-mail]>
Cc: Liam Mark <[e-mail]>
Cc: Pratik Patel <[e-mail]>
Cc: Brian Starkey <[e-mail]>
Cc: Vincent Donnefort <[e-mail]>
Cc: Sudipto Paul <[e-mail]>
Cc: Andrew F. Davis <[e-mail]>
Cc: Christoph Hellwig <[e-mail]>
Cc: Chenbo Feng <[e-mail]>
Cc: Alistair Strachan <[e-mail]>
Cc: Hridya Valsaraju <[e-mail]>
Cc: Sandeep Patil <[e-mail]>
Cc: Hillf Danton <[e-mail]>
Cc: Dave Airlie <[e-mail]>
Cc: [e-mail]
Reviewed-by: Benjamin Gaignard <[e-mail]>
Reviewed-by: Brian Starkey <[e-mail]>
Acked-by: Sandeep Patil <[e-mail]>
Acked-by: Laura Abbott <[e-mail]>
Tested-by: Ayan Kumar Halder <[e-mail]>
Signed-off-by: John Stultz <[e-mail]>
Signed-off-by: Sumit Semwal <[e-mail]>
Link: https://patchwork.freedesktop.org/patch/msgid/[e-mail]

tools/testing/selftests/dmabuf-heaps/Makefile

···
+# SPDX-License-Identifier: GPL-2.0
+CFLAGS += -static -O3 -Wl,-no-as-needed -Wall -I../../../../usr/include
+
+TEST_GEN_PROGS = dmabuf-heap
+
+include ../lib.mk

tools/testing/selftests/dmabuf-heaps/dmabuf-heap.c

···
+// SPDX-License-Identifier: GPL-2.0
+
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/ioctl.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+
+#include <linux/dma-buf.h>
+#include <drm/drm.h>
+
+#include "../../../../include/uapi/linux/dma-heap.h"
+
+#define DEVPATH "/dev/dma_heap"
+
+static int check_vgem(int fd)
+{
+	drm_version_t version = { 0 };
+	char name[5];
+	int ret;
+
+	version.name_len = 4;
+	version.name = name;
+
+	ret = ioctl(fd, DRM_IOCTL_VERSION, &version);
+	if (ret)
+		return 0;
+
+	return !strcmp(name, "vgem");
+}
+
+static int open_vgem(void)
+{
+	int i, fd;
+	const char *drmstr = "/dev/dri/card";
+
+	fd = -1;
+	for (i = 0; i < 16; i++) {
+		char name[80];
+
+		snprintf(name, 80, "%s%u", drmstr, i);
+
+		fd = open(name, O_RDWR);
+		if (fd < 0)
+			continue;
+
+		if (!check_vgem(fd)) {
+			close(fd);
+			fd = -1;
+			continue;
+		} else {
+			break;
+		}
+	}
+	return fd;
+}
+
+static int import_vgem_fd(int vgem_fd, int dma_buf_fd, uint32_t *handle)
+{
+	struct drm_prime_handle import_handle = {
+		.fd = dma_buf_fd,
+		.flags = 0,
+		.handle = 0,
+	 };
+	int ret;
+
+	ret = ioctl(vgem_fd, DRM_IOCTL_PRIME_FD_TO_HANDLE, &import_handle);
+	if (ret == 0)
+		*handle = import_handle.handle;
+	return ret;
+}
+
+static void close_handle(int vgem_fd, uint32_t handle)
+{
+	struct drm_gem_close close = {
+		.handle = handle,
+	};
+
+	ioctl(vgem_fd, DRM_IOCTL_GEM_CLOSE, &close);
+}
+
+static int dmabuf_heap_open(char *name)
+{
+	int ret, fd;
+	char buf[256];
+
+	ret = snprintf(buf, 256, "%s/%s", DEVPATH, name);
+	if (ret < 0) {
+		printf("snprintf failed!\n");
+		return ret;
+	}
+
+	fd = open(buf, O_RDWR);
+	if (fd < 0)
+		printf("open %s failed!\n", buf);
+	return fd;
+}
+
+static int dmabuf_heap_alloc_fdflags(int fd, size_t len, unsigned int fd_flags,
+				     unsigned int heap_flags, int *dmabuf_fd)
+{
+	struct dma_heap_allocation_data data = {
+		.len = len,
+		.fd = 0,
+		.fd_flags = fd_flags,
+		.heap_flags = heap_flags,
+	};
+	int ret;
+
+	if (!dmabuf_fd)
+		return -EINVAL;
+
+	ret = ioctl(fd, DMA_HEAP_IOC_ALLOC, &data);
+	if (ret < 0)
+		return ret;
+	*dmabuf_fd = (int)data.fd;
+	return ret;
+}
+
+static int dmabuf_heap_alloc(int fd, size_t len, unsigned int flags,
+			     int *dmabuf_fd)
+{
+	return dmabuf_heap_alloc_fdflags(fd, len, O_RDWR | O_CLOEXEC, flags,
+					 dmabuf_fd);
+}
+
+static void dmabuf_sync(int fd, int start_stop)
+{
+	struct dma_buf_sync sync = {
+		.flags = start_stop | DMA_BUF_SYNC_RW,
+	};
+	int ret;
+
+	ret = ioctl(fd, DMA_BUF_IOCTL_SYNC, &sync);
+	if (ret)
+		printf("sync failed %d\n", errno);
+}
+
+#define ONE_MEG (1024 * 1024)
+
+static int test_alloc_and_import(char *heap_name)
+{
+	int heap_fd = -1, dmabuf_fd = -1, importer_fd = -1;
+	uint32_t handle = 0;
+	void *p = NULL;
+	int ret;
+
+	printf("Testing heap: %s\n", heap_name);
+
+	heap_fd = dmabuf_heap_open(heap_name);
+	if (heap_fd < 0)
+		return -1;
+
+	printf("Allocating 1 MEG\n");
+	ret = dmabuf_heap_alloc(heap_fd, ONE_MEG, 0, &dmabuf_fd);
+	if (ret) {
+		printf("Allocation Failed!\n");
+		ret = -1;
+		goto out;
+	}
+	/* mmap and write a simple pattern */
+	p = mmap(NULL,
+		 ONE_MEG,
+		 PROT_READ | PROT_WRITE,
+		 MAP_SHARED,
+		 dmabuf_fd,
+		 0);
+	if (p == MAP_FAILED) {
+		printf("mmap() failed: %m\n");
+		ret = -1;
+		goto out;
+	}
+	printf("mmap passed\n");
+
+	dmabuf_sync(dmabuf_fd, DMA_BUF_SYNC_START);
+	memset(p, 1, ONE_MEG / 2);
+	memset((char *)p + ONE_MEG / 2, 0, ONE_MEG / 2);
+	dmabuf_sync(dmabuf_fd, DMA_BUF_SYNC_END);
+
+	importer_fd = open_vgem();
+	if (importer_fd < 0) {
+		ret = importer_fd;
+		printf("Failed to open vgem\n");
+		goto out;
+	}
+
+	ret = import_vgem_fd(importer_fd, dmabuf_fd, &handle);
+	if (ret < 0) {
+		printf("Failed to import buffer\n");
+		goto out;
+	}
+	printf("import passed\n");
+
+	dmabuf_sync(dmabuf_fd, DMA_BUF_SYNC_START);
+	memset(p, 0xff, ONE_MEG);
+	dmabuf_sync(dmabuf_fd, DMA_BUF_SYNC_END);
+	printf("syncs passed\n");
+
+	close_handle(importer_fd, handle);
+	ret = 0;
+
+out:
+	if (p)
+		munmap(p, ONE_MEG);
+	if (importer_fd >= 0)
+		close(importer_fd);
+	if (dmabuf_fd >= 0)
+		close(dmabuf_fd);
+	if (heap_fd >= 0)
+		close(heap_fd);
+
+	return ret;
+}
+
+/* Test the ioctl version compatibility w/ a smaller structure then expected */
+static int dmabuf_heap_alloc_older(int fd, size_t len, unsigned int flags,
+				   int *dmabuf_fd)
+{
+	int ret;
+	unsigned int older_alloc_ioctl;
+	struct dma_heap_allocation_data_smaller {
+		__u64 len;
+		__u32 fd;
+		__u32 fd_flags;
+	} data = {
+		.len = len,
+		.fd = 0,
+		.fd_flags = O_RDWR | O_CLOEXEC,
+	};
+
+	older_alloc_ioctl = _IOWR(DMA_HEAP_IOC_MAGIC, 0x0,
+				  struct dma_heap_allocation_data_smaller);
+	if (!dmabuf_fd)
+		return -EINVAL;
+
+	ret = ioctl(fd, older_alloc_ioctl, &data);
+	if (ret < 0)
+		return ret;
+	*dmabuf_fd = (int)data.fd;
+	return ret;
+}
+
+/* Test the ioctl version compatibility w/ a larger structure then expected */
+static int dmabuf_heap_alloc_newer(int fd, size_t len, unsigned int flags,
+				   int *dmabuf_fd)
+{
+	int ret;
+	unsigned int newer_alloc_ioctl;
+	struct dma_heap_allocation_data_bigger {
+		__u64 len;
+		__u32 fd;
+		__u32 fd_flags;
+		__u64 heap_flags;
+		__u64 garbage1;
+		__u64 garbage2;
+		__u64 garbage3;
+	} data = {
+		.len = len,
+		.fd = 0,
+		.fd_flags = O_RDWR | O_CLOEXEC,
+		.heap_flags = flags,
+		.garbage1 = 0xffffffff,
+		.garbage2 = 0x88888888,
+		.garbage3 = 0x11111111,
+	};
+
+	newer_alloc_ioctl = _IOWR(DMA_HEAP_IOC_MAGIC, 0x0,
+				  struct dma_heap_allocation_data_bigger);
+	if (!dmabuf_fd)
+		return -EINVAL;
+
+	ret = ioctl(fd, newer_alloc_ioctl, &data);
+	if (ret < 0)
+		return ret;
+
+	*dmabuf_fd = (int)data.fd;
+	return ret;
+}
+
+static int test_alloc_compat(char *heap_name)
+{
+	int heap_fd = -1, dmabuf_fd = -1;
+	int ret;
+
+	heap_fd = dmabuf_heap_open(heap_name);
+	if (heap_fd < 0)
+		return -1;
+
+	printf("Testing (theoretical)older alloc compat\n");
+	ret = dmabuf_heap_alloc_older(heap_fd, ONE_MEG, 0, &dmabuf_fd);
+	if (ret) {
+		printf("Older compat allocation failed!\n");
+		ret = -1;
+		goto out;
+	}
+	close(dmabuf_fd);
+
+	printf("Testing (theoretical)newer alloc compat\n");
+	ret = dmabuf_heap_alloc_newer(heap_fd, ONE_MEG, 0, &dmabuf_fd);
+	if (ret) {
+		printf("Newer compat allocation failed!\n");
+		ret = -1;
+		goto out;
+	}
+	printf("Ioctl compatibility tests passed\n");
+out:
+	if (dmabuf_fd >= 0)
+		close(dmabuf_fd);
+	if (heap_fd >= 0)
+		close(heap_fd);
+
+	return ret;
+}
+
+static int test_alloc_errors(char *heap_name)
+{
+	int heap_fd = -1, dmabuf_fd = -1;
+	int ret;
+
+	heap_fd = dmabuf_heap_open(heap_name);
+	if (heap_fd < 0)
+		return -1;
+
+	printf("Testing expected error cases\n");
+	ret = dmabuf_heap_alloc(0, ONE_MEG, 0x111111, &dmabuf_fd);
+	if (!ret) {
+		printf("Did not see expected error (invalid fd)!\n");
+		ret = -1;
+		goto out;
+	}
+
+	ret = dmabuf_heap_alloc(heap_fd, ONE_MEG, 0x111111, &dmabuf_fd);
+	if (!ret) {
+		printf("Did not see expected error (invalid heap flags)!\n");
+		ret = -1;
+		goto out;
+	}
+
+	ret = dmabuf_heap_alloc_fdflags(heap_fd, ONE_MEG,
+					~(O_RDWR | O_CLOEXEC), 0, &dmabuf_fd);
+	if (!ret) {
+		printf("Did not see expected error (invalid fd flags)!\n");
+		ret = -1;
+		goto out;
+	}
+
+	printf("Expected error checking passed\n");
+out:
+	if (dmabuf_fd >= 0)
+		close(dmabuf_fd);
+	if (heap_fd >= 0)
+		close(heap_fd);
+
+	return ret;
+}
+
+int main(void)
+{
+	DIR *d;
+	struct dirent *dir;
+	int ret = -1;
+
+	d = opendir(DEVPATH);
+	if (!d) {
+		printf("No %s directory?\n", DEVPATH);
+		return -1;
+	}
+
+	while ((dir = readdir(d)) != NULL) {
+		if (!strncmp(dir->d_name, ".", 2))
+			continue;
+		if (!strncmp(dir->d_name, "..", 3))
+			continue;
+
+		ret = test_alloc_and_import(dir->d_name);
+		if (ret)
+			break;
+
+		ret = test_alloc_compat(dir->d_name);
+		if (ret)
+			break;
+
+		ret = test_alloc_errors(dir->d_name);
+		if (ret)
+			break;
+	}
+	closedir(d);
+
+	return ret;
+}