test/fd-install.c - pub/scm/linux/kernel/git/axboe/liburing - Git at Google

 /* SPDX-License-Identifier: MIT */
 /*
  * Description: test installing a direct descriptor into the regular
  *		file table
  *
  */
 #include <errno.h>
 #include <stdio.h>
 #include <unistd.h>
 #include <stdlib.h>
 #include <string.h>
 #include <fcntl.h>

 #include "liburing.h"
 #include "helpers.h"

 static int no_fd_install;

 /* test that O_CLOEXEC is accepted, and others are not */
 static int test_flags(struct io_uring *ring, int async)
 {
 	struct io_uring_sqe *sqe;
 	struct io_uring_cqe *cqe;
 	int ret, fds[2], fd;

 	if (pipe(fds) < 0) {
 		perror("pipe");
 		return T_EXIT_FAIL;
 	}

 	ret = io_uring_register_files(ring, &fds[0], 1);
 	if (ret) {
 		fprintf(stderr, "failed register files %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	/* check that setting an invalid flag fails */
 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_fixed_fd_install(sqe, 0, 1U << 17);
 	io_uring_submit(ring);

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res != -EINVAL) {
 		fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}
 	io_uring_cqe_seen(ring, cqe);

 	/* check that IORING_FIXED_FD_NO_CLOEXEC is accepted */
 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_fixed_fd_install(sqe, 0, IORING_FIXED_FD_NO_CLOEXEC);
 	if (async)
 		sqe->flags |= IOSQE_ASYNC;
 	io_uring_submit(ring);

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res < 0) {
 		fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}
 	fd = cqe->res;
 	io_uring_cqe_seen(ring, cqe);

 	close(fds[0]);
 	close(fds[1]);
 	close(fd);
 	io_uring_unregister_files(ring);

 	return T_EXIT_PASS;
 }

 static int test_linked(struct io_uring *ring)
 {
 	struct io_uring_sqe *sqe;
 	struct io_uring_cqe *cqe;
 	int ret, fds[2], fd, i;

 	if (pipe(fds) < 0) {
 		perror("pipe");
 		return T_EXIT_FAIL;
 	}

 	ret = io_uring_register_files(ring, &fds[0], 1);
 	if (ret) {
 		fprintf(stderr, "failed register files %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_nop(sqe);
 	sqe->flags |= IOSQE_IO_LINK;
 	sqe->user_data = 1;

 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_fixed_fd_install(sqe, 0, 0);
 	sqe->user_data = 2;

 	ret = io_uring_submit(ring);
 	if (ret != 2) {
 		fprintf(stderr, "submit: %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	fd = -1;
 	for (i = 0; i < 2; i++) {
 		ret = io_uring_wait_cqe(ring, &cqe);
 		if (ret) {
 			fprintf(stderr, "wait cqe %d\n", ret);
 			return T_EXIT_FAIL;
 		}
 		if (cqe->res < 0) {
 			fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
 			return T_EXIT_FAIL;
 		}
 		if (cqe->user_data == 2)
 			fd = cqe->res;
 		io_uring_cqe_seen(ring, cqe);
 	}

 	close(fds[0]);
 	close(fds[1]);
 	if (fd != -1)
 		close(fd);
 	io_uring_unregister_files(ring);
 	return T_EXIT_PASS;
 }

 /* test not setting IOSQE_FIXED_FILE */
 static int test_not_fixed(struct io_uring *ring)
 {
 	struct io_uring_sqe *sqe;
 	struct io_uring_cqe *cqe;
 	int ret, fds[2];

 	if (pipe(fds) < 0) {
 		perror("pipe");
 		return T_EXIT_FAIL;
 	}

 	ret = io_uring_register_files(ring, &fds[0], 1);
 	if (ret) {
 		fprintf(stderr, "failed register files %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_fixed_fd_install(sqe, 0, 0);
 	sqe->flags &= ~IOSQE_FIXED_FILE;
 	io_uring_submit(ring);

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res != -EBADF) {
 		fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}

 	io_uring_cqe_seen(ring, cqe);

 	close(fds[0]);
 	close(fds[1]);
 	io_uring_unregister_files(ring);

 	return T_EXIT_PASS;
 }

 /* test invalid direct descriptor indexes */
 static int test_bad_fd(struct io_uring *ring, int some_fd)
 {
 	struct io_uring_sqe *sqe;
 	struct io_uring_cqe *cqe;
 	int ret;

 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_fixed_fd_install(sqe, some_fd, 0);
 	io_uring_submit(ring);

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res != -EBADF) {
 		fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}

 	io_uring_cqe_seen(ring, cqe);
 	return T_EXIT_PASS;
 }

 /* test basic functionality of shifting a direct descriptor to a normal file */
 static int test_working(struct io_uring *ring)
 {
 	struct io_uring_sqe *sqe;
 	struct io_uring_cqe *cqe;
 	int ret, fds[2];
 	char buf[32];

 	if (pipe(fds) < 0) {
 		perror("pipe");
 		return T_EXIT_FAIL;
 	}

 	/* register read side */
 	ret = io_uring_register_files(ring, &fds[0], 1);
 	if (ret) {
 		fprintf(stderr, "failed register files %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	/* close normal descriptor */
 	close(fds[0]);

 	/* normal read should fail */
 	ret = read(fds[0], buf, 1);
 	if (ret != -1) {
 		fprintf(stderr, "unexpected read ret %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (errno != EBADF) {
 		fprintf(stderr, "unexpected read failure %d\n", errno);
 		return T_EXIT_FAIL;
 	}

 	/* verify we can read the data */
 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_read(sqe, 0, buf, sizeof(buf), 0);
 	sqe->flags |= IOSQE_FIXED_FILE;
 	io_uring_submit(ring);

 	/* put some data in the pipe */
 	ret = write(fds[1], "Hello", 5);
 	if (ret < 0) {
 		perror("write");
 		return T_EXIT_FAIL;
 	} else if (ret != 5) {
 		fprintf(stderr, "short write %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res != 5) {
 		fprintf(stderr, "weird pipe read ret %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}
 	io_uring_cqe_seen(ring, cqe);

 	/* fixed pipe read worked, now re-install as a regular fd */
 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_fixed_fd_install(sqe, 0, 0);
 	io_uring_submit(ring);

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res == -EINVAL) {
 		no_fd_install = 1;
 		return T_EXIT_SKIP;
 	}
 	if (cqe->res < 0) {
 		fprintf(stderr, "failed install fd: %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}
 	/* stash new pipe read side fd in old spot */
 	fds[0] = cqe->res;
 	io_uring_cqe_seen(ring, cqe);

 	ret = write(fds[1], "Hello", 5);
 	if (ret < 0) {
 		perror("write");
 		return T_EXIT_FAIL;
 	} else if (ret != 5) {
 		fprintf(stderr, "short write %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	/* normal pipe read should now work with new fd */
 	ret = read(fds[0], buf, sizeof(buf));
 	if (ret != 5) {
 		fprintf(stderr, "unexpected read ret %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	/* close fixed file */
 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_close_direct(sqe, 0);
 	io_uring_submit(ring);

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res) {
 		fprintf(stderr, "close fixed fd %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}
 	io_uring_cqe_seen(ring, cqe);

 	ret = write(fds[1], "Hello", 5);
 	if (ret < 0) {
 		perror("write");
 		return T_EXIT_FAIL;
 	} else if (ret != 5) {
 		fprintf(stderr, "short write %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	/* normal pipe read should still work with new fd */
 	ret = read(fds[0], buf, sizeof(buf));
 	if (ret != 5) {
 		fprintf(stderr, "unexpected read ret %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	/* fixed fd pipe read should now fail */
 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_read(sqe, 0, buf, sizeof(buf), 0);
 	sqe->flags = IOSQE_FIXED_FILE;
 	io_uring_submit(ring);

 	/* put some data in the pipe */
 	ret = write(fds[1], "Hello", 5);
 	if (ret < 0) {
 		perror("write");
 		return T_EXIT_FAIL;
 	} else if (ret != 5) {
 		fprintf(stderr, "short write %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res != -EBADF) {
 		fprintf(stderr, "weird pipe read ret %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}
 	io_uring_cqe_seen(ring, cqe);

 	close(fds[0]);
 	close(fds[1]);
 	io_uring_unregister_files(ring);
 	return T_EXIT_PASS;
 }

 static int test_creds(struct io_uring *ring, int async)
 {
 	struct io_uring_sqe *sqe;
 	struct io_uring_cqe *cqe;
 	int cred_id, ret, fds[2];

 	if (pipe(fds) < 0) {
 		perror("pipe");
 		return T_EXIT_FAIL;
 	}

 	ret = io_uring_register_files(ring, &fds[0], 1);
 	if (ret) {
 		fprintf(stderr, "failed register files %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	cred_id = io_uring_register_personality(ring);
 	if (cred_id < 0) {
 		fprintf(stderr, "Failed registering creds: %d\n", cred_id);
 		return T_EXIT_FAIL;
 	}

 	/* check that asking for creds fails */
 	sqe = io_uring_get_sqe(ring);
 	io_uring_prep_fixed_fd_install(sqe, 0, 0);
 	if (async)
 		sqe->flags |= IOSQE_ASYNC;
 	sqe->personality = cred_id;
 	io_uring_submit(ring);

 	ret = io_uring_wait_cqe(ring, &cqe);
 	if (ret) {
 		fprintf(stderr, "wait cqe %d\n", ret);
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res > 0) {
 		fprintf(stderr, "install succeeded with creds\n");
 		return T_EXIT_FAIL;
 	}
 	if (cqe->res != -EPERM) {
 		fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
 		return T_EXIT_FAIL;
 	}
 	io_uring_cqe_seen(ring, cqe);

 	close(fds[0]);
 	close(fds[1]);
 	io_uring_unregister_files(ring);
 	io_uring_unregister_personality(ring, cred_id);
 	return T_EXIT_PASS;
 }

 int main(int argc, char *argv[])
 {
 	struct io_uring ring;
 	int ret;

 	if (argc > 1)
 		return T_EXIT_SKIP;

 	ret = io_uring_queue_init(4, &ring, 0);
 	if (ret) {
 		fprintf(stderr, "ring setup failed: %d\n", ret);
 		return T_EXIT_FAIL;
 	}

 	ret = test_working(&ring);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_working failed\n");
 		return ret;
 	}
 	if (no_fd_install)
 		return T_EXIT_SKIP;

 	ret = test_bad_fd(&ring, 0);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_bad_fd 0 failed\n");
 		return ret;
 	}

 	ret = test_bad_fd(&ring, 500);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_bad_fd 500 failed\n");
 		return ret;
 	}

 	ret = test_not_fixed(&ring);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_not_fixed failed\n");
 		return ret;
 	}

 	ret = test_flags(&ring, 0);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_flags 0 failed\n");
 		return ret;
 	}

 	ret = test_flags(&ring, 1);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_flags 1 failed\n");
 		return ret;
 	}

 	ret = test_creds(&ring, 0);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_creds 0 failed\n");
 		return ret;
 	}

 	ret = test_creds(&ring, 1);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_creds 1 failed\n");
 		return ret;
 	}

 	ret = test_linked(&ring);
 	if (ret != T_EXIT_PASS) {
 		if (ret == T_EXIT_FAIL)
 			fprintf(stderr, "test_linked failed\n");
 		return ret;
 	}

 	return T_EXIT_PASS;
 }
	/* SPDX-License-Identifier: MIT */
	/*
	* Description: test installing a direct descriptor into the regular
	* file table
	*
	*/
	#include <errno.h>
	#include <stdio.h>
	#include <unistd.h>
	#include <stdlib.h>
	#include <string.h>
	#include <fcntl.h>

	#include "liburing.h"
	#include "helpers.h"

	static int no_fd_install;

	/* test that O_CLOEXEC is accepted, and others are not */
	static int test_flags(struct io_uring *ring, int async)
	{
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe;
	int ret, fds[2], fd;

	if (pipe(fds) < 0) {
	perror("pipe");
	return T_EXIT_FAIL;
	}

	ret = io_uring_register_files(ring, &fds[0], 1);
	if (ret) {
	fprintf(stderr, "failed register files %d\n", ret);
	return T_EXIT_FAIL;
	}

	/* check that setting an invalid flag fails */
	sqe = io_uring_get_sqe(ring);
	io_uring_prep_fixed_fd_install(sqe, 0, 1U << 17);
	io_uring_submit(ring);

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res != -EINVAL) {
	fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
	return T_EXIT_FAIL;
	}
	io_uring_cqe_seen(ring, cqe);

	/* check that IORING_FIXED_FD_NO_CLOEXEC is accepted */
	sqe = io_uring_get_sqe(ring);
	io_uring_prep_fixed_fd_install(sqe, 0, IORING_FIXED_FD_NO_CLOEXEC);
	if (async)
	sqe->flags \|= IOSQE_ASYNC;
	io_uring_submit(ring);

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res < 0) {
	fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
	return T_EXIT_FAIL;
	}
	fd = cqe->res;
	io_uring_cqe_seen(ring, cqe);

	close(fds[0]);
	close(fds[1]);
	close(fd);
	io_uring_unregister_files(ring);

	return T_EXIT_PASS;
	}

	static int test_linked(struct io_uring *ring)
	{
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe;
	int ret, fds[2], fd, i;

	if (pipe(fds) < 0) {
	perror("pipe");
	return T_EXIT_FAIL;
	}

	ret = io_uring_register_files(ring, &fds[0], 1);
	if (ret) {
	fprintf(stderr, "failed register files %d\n", ret);
	return T_EXIT_FAIL;
	}

	sqe = io_uring_get_sqe(ring);
	io_uring_prep_nop(sqe);
	sqe->flags \|= IOSQE_IO_LINK;
	sqe->user_data = 1;

	sqe = io_uring_get_sqe(ring);
	io_uring_prep_fixed_fd_install(sqe, 0, 0);
	sqe->user_data = 2;

	ret = io_uring_submit(ring);
	if (ret != 2) {
	fprintf(stderr, "submit: %d\n", ret);
	return T_EXIT_FAIL;
	}

	fd = -1;
	for (i = 0; i < 2; i++) {
	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res < 0) {
	fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
	return T_EXIT_FAIL;
	}
	if (cqe->user_data == 2)
	fd = cqe->res;
	io_uring_cqe_seen(ring, cqe);
	}

	close(fds[0]);
	close(fds[1]);
	if (fd != -1)
	close(fd);
	io_uring_unregister_files(ring);
	return T_EXIT_PASS;
	}

	/* test not setting IOSQE_FIXED_FILE */
	static int test_not_fixed(struct io_uring *ring)
	{
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe;
	int ret, fds[2];

	if (pipe(fds) < 0) {
	perror("pipe");
	return T_EXIT_FAIL;
	}

	ret = io_uring_register_files(ring, &fds[0], 1);
	if (ret) {
	fprintf(stderr, "failed register files %d\n", ret);
	return T_EXIT_FAIL;
	}

	sqe = io_uring_get_sqe(ring);
	io_uring_prep_fixed_fd_install(sqe, 0, 0);
	sqe->flags &= ~IOSQE_FIXED_FILE;
	io_uring_submit(ring);

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res != -EBADF) {
	fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
	return T_EXIT_FAIL;
	}

	io_uring_cqe_seen(ring, cqe);

	close(fds[0]);
	close(fds[1]);
	io_uring_unregister_files(ring);

	return T_EXIT_PASS;
	}

	/* test invalid direct descriptor indexes */
	static int test_bad_fd(struct io_uring *ring, int some_fd)
	{
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe;
	int ret;

	sqe = io_uring_get_sqe(ring);
	io_uring_prep_fixed_fd_install(sqe, some_fd, 0);
	io_uring_submit(ring);

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res != -EBADF) {
	fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
	return T_EXIT_FAIL;
	}

	io_uring_cqe_seen(ring, cqe);
	return T_EXIT_PASS;
	}

	/* test basic functionality of shifting a direct descriptor to a normal file */
	static int test_working(struct io_uring *ring)
	{
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe;
	int ret, fds[2];
	char buf[32];

	if (pipe(fds) < 0) {
	perror("pipe");
	return T_EXIT_FAIL;
	}

	/* register read side */
	ret = io_uring_register_files(ring, &fds[0], 1);
	if (ret) {
	fprintf(stderr, "failed register files %d\n", ret);
	return T_EXIT_FAIL;
	}

	/* close normal descriptor */
	close(fds[0]);

	/* normal read should fail */
	ret = read(fds[0], buf, 1);
	if (ret != -1) {
	fprintf(stderr, "unexpected read ret %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (errno != EBADF) {
	fprintf(stderr, "unexpected read failure %d\n", errno);
	return T_EXIT_FAIL;
	}

	/* verify we can read the data */
	sqe = io_uring_get_sqe(ring);
	io_uring_prep_read(sqe, 0, buf, sizeof(buf), 0);
	sqe->flags \|= IOSQE_FIXED_FILE;
	io_uring_submit(ring);

	/* put some data in the pipe */
	ret = write(fds[1], "Hello", 5);
	if (ret < 0) {
	perror("write");
	return T_EXIT_FAIL;
	} else if (ret != 5) {
	fprintf(stderr, "short write %d\n", ret);
	return T_EXIT_FAIL;
	}

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res != 5) {
	fprintf(stderr, "weird pipe read ret %d\n", cqe->res);
	return T_EXIT_FAIL;
	}
	io_uring_cqe_seen(ring, cqe);

	/* fixed pipe read worked, now re-install as a regular fd */
	sqe = io_uring_get_sqe(ring);
	io_uring_prep_fixed_fd_install(sqe, 0, 0);
	io_uring_submit(ring);

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res == -EINVAL) {
	no_fd_install = 1;
	return T_EXIT_SKIP;
	}
	if (cqe->res < 0) {
	fprintf(stderr, "failed install fd: %d\n", cqe->res);
	return T_EXIT_FAIL;
	}
	/* stash new pipe read side fd in old spot */
	fds[0] = cqe->res;
	io_uring_cqe_seen(ring, cqe);

	ret = write(fds[1], "Hello", 5);
	if (ret < 0) {
	perror("write");
	return T_EXIT_FAIL;
	} else if (ret != 5) {
	fprintf(stderr, "short write %d\n", ret);
	return T_EXIT_FAIL;
	}

	/* normal pipe read should now work with new fd */
	ret = read(fds[0], buf, sizeof(buf));
	if (ret != 5) {
	fprintf(stderr, "unexpected read ret %d\n", ret);
	return T_EXIT_FAIL;
	}

	/* close fixed file */
	sqe = io_uring_get_sqe(ring);
	io_uring_prep_close_direct(sqe, 0);
	io_uring_submit(ring);

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res) {
	fprintf(stderr, "close fixed fd %d\n", cqe->res);
	return T_EXIT_FAIL;
	}
	io_uring_cqe_seen(ring, cqe);

	ret = write(fds[1], "Hello", 5);
	if (ret < 0) {
	perror("write");
	return T_EXIT_FAIL;
	} else if (ret != 5) {
	fprintf(stderr, "short write %d\n", ret);
	return T_EXIT_FAIL;
	}

	/* normal pipe read should still work with new fd */
	ret = read(fds[0], buf, sizeof(buf));
	if (ret != 5) {
	fprintf(stderr, "unexpected read ret %d\n", ret);
	return T_EXIT_FAIL;
	}

	/* fixed fd pipe read should now fail */
	sqe = io_uring_get_sqe(ring);
	io_uring_prep_read(sqe, 0, buf, sizeof(buf), 0);
	sqe->flags = IOSQE_FIXED_FILE;
	io_uring_submit(ring);

	/* put some data in the pipe */
	ret = write(fds[1], "Hello", 5);
	if (ret < 0) {
	perror("write");
	return T_EXIT_FAIL;
	} else if (ret != 5) {
	fprintf(stderr, "short write %d\n", ret);
	return T_EXIT_FAIL;
	}

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res != -EBADF) {
	fprintf(stderr, "weird pipe read ret %d\n", cqe->res);
	return T_EXIT_FAIL;
	}
	io_uring_cqe_seen(ring, cqe);

	close(fds[0]);
	close(fds[1]);
	io_uring_unregister_files(ring);
	return T_EXIT_PASS;
	}

	static int test_creds(struct io_uring *ring, int async)
	{
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe;
	int cred_id, ret, fds[2];

	if (pipe(fds) < 0) {
	perror("pipe");
	return T_EXIT_FAIL;
	}

	ret = io_uring_register_files(ring, &fds[0], 1);
	if (ret) {
	fprintf(stderr, "failed register files %d\n", ret);
	return T_EXIT_FAIL;
	}

	cred_id = io_uring_register_personality(ring);
	if (cred_id < 0) {
	fprintf(stderr, "Failed registering creds: %d\n", cred_id);
	return T_EXIT_FAIL;
	}

	/* check that asking for creds fails */
	sqe = io_uring_get_sqe(ring);
	io_uring_prep_fixed_fd_install(sqe, 0, 0);
	if (async)
	sqe->flags \|= IOSQE_ASYNC;
	sqe->personality = cred_id;
	io_uring_submit(ring);

	ret = io_uring_wait_cqe(ring, &cqe);
	if (ret) {
	fprintf(stderr, "wait cqe %d\n", ret);
	return T_EXIT_FAIL;
	}
	if (cqe->res > 0) {
	fprintf(stderr, "install succeeded with creds\n");
	return T_EXIT_FAIL;
	}
	if (cqe->res != -EPERM) {
	fprintf(stderr, "unexpected cqe res %d\n", cqe->res);
	return T_EXIT_FAIL;
	}
	io_uring_cqe_seen(ring, cqe);

	close(fds[0]);
	close(fds[1]);
	io_uring_unregister_files(ring);
	io_uring_unregister_personality(ring, cred_id);
	return T_EXIT_PASS;
	}

	int main(int argc, char *argv[])
	{
	struct io_uring ring;
	int ret;

	if (argc > 1)
	return T_EXIT_SKIP;

	ret = io_uring_queue_init(4, &ring, 0);
	if (ret) {
	fprintf(stderr, "ring setup failed: %d\n", ret);
	return T_EXIT_FAIL;
	}

	ret = test_working(&ring);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_working failed\n");
	return ret;
	}
	if (no_fd_install)
	return T_EXIT_SKIP;

	ret = test_bad_fd(&ring, 0);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_bad_fd 0 failed\n");
	return ret;
	}

	ret = test_bad_fd(&ring, 500);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_bad_fd 500 failed\n");
	return ret;
	}

	ret = test_not_fixed(&ring);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_not_fixed failed\n");
	return ret;
	}

	ret = test_flags(&ring, 0);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_flags 0 failed\n");
	return ret;
	}

	ret = test_flags(&ring, 1);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_flags 1 failed\n");
	return ret;
	}

	ret = test_creds(&ring, 0);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_creds 0 failed\n");
	return ret;
	}

	ret = test_creds(&ring, 1);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_creds 1 failed\n");
	return ret;
	}

	ret = test_linked(&ring);
	if (ret != T_EXIT_PASS) {
	if (ret == T_EXIT_FAIL)
	fprintf(stderr, "test_linked failed\n");
	return ret;
	}

	return T_EXIT_PASS;
	}