/* SPDX-License-Identifier: MIT */
/*
 * Description: basic read/write tests for io_uring passthrough commands
 */
#include <errno.h>
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <string.h>

#include "helpers.h"
#include "liburing.h"
#include "../src/syscall.h"
#include "nvme.h"

#define FILE_SIZE	(256 * 1024)
#define BS		8192
#define BUFFERS		(FILE_SIZE / BS)

static struct iovec *vecs;
static int no_pt;

/*
 * Each offset in the file has the ((test_case / 2) * FILE_SIZE)
 * + (offset / sizeof(int)) stored for every
 * sizeof(int) address.
 */
static int verify_buf(int tc, void *buf, off_t off)
{
	int i, u_in_buf = BS / sizeof(unsigned int);
	unsigned int *ptr;

	off /= sizeof(unsigned int);
	off += (tc / 2) * FILE_SIZE;
	ptr = buf;
	for (i = 0; i < u_in_buf; i++) {
		if (off != *ptr) {
			fprintf(stderr, "Found %u, wanted %llu\n", *ptr,
					(unsigned long long) off);
			return 1;
		}
		ptr++;
		off++;
	}

	return 0;
}

static int fill_pattern(int tc)
{
	unsigned int val, *ptr;
	int i, j;
	int u_in_buf = BS / sizeof(val);

	val = (tc / 2) * FILE_SIZE;
	for (i = 0; i < BUFFERS; i++) {
		ptr = vecs[i].iov_base;
		for (j = 0; j < u_in_buf; j++) {
			*ptr = val;
			val++;
			ptr++;
		}
	}

	return 0;
}

static int __test_io(const char *file, struct io_uring *ring, int tc, int read,
		     int sqthread, int fixed, int nonvec)
{
	struct io_uring_sqe *sqe;
	struct io_uring_cqe *cqe;
	struct nvme_uring_cmd *cmd;
	int open_flags;
	int do_fixed;
	int i, ret, fd = -1;
	off_t offset;
	__u64 slba;
	__u32 nlb;

	if (read)
		open_flags = O_RDONLY;
	else
		open_flags = O_WRONLY;

	if (fixed) {
		ret = t_register_buffers(ring, vecs, BUFFERS);
		if (ret == T_SETUP_SKIP)
			return 0;
		if (ret != T_SETUP_OK) {
			fprintf(stderr, "buffer reg failed: %d\n", ret);
			goto err;
		}
	}

	fd = open(file, open_flags);
	if (fd < 0) {
		perror("file open");
		goto err;
	}

	if (sqthread) {
		ret = io_uring_register_files(ring, &fd, 1);
		if (ret) {
			fprintf(stderr, "file reg failed: %d\n", ret);
			goto err;
		}
	}

	if (!read)
		fill_pattern(tc);

	offset = 0;
	for (i = 0; i < BUFFERS; i++) {
		sqe = io_uring_get_sqe(ring);
		if (!sqe) {
			fprintf(stderr, "sqe get failed\n");
			goto err;
		}
		if (read) {
			int use_fd = fd;

			do_fixed = fixed;

			if (sqthread)
				use_fd = 0;
			if (fixed && (i & 1))
				do_fixed = 0;
			if (do_fixed) {
				io_uring_prep_read_fixed(sqe, use_fd, vecs[i].iov_base,
								vecs[i].iov_len,
								offset, i);
				sqe->cmd_op = NVME_URING_CMD_IO;
			} else if (nonvec) {
				io_uring_prep_read(sqe, use_fd, vecs[i].iov_base,
							vecs[i].iov_len, offset);
				sqe->cmd_op = NVME_URING_CMD_IO;
			} else {
				io_uring_prep_readv(sqe, use_fd, &vecs[i], 1,
								offset);
				sqe->cmd_op = NVME_URING_CMD_IO_VEC;
			}
		} else {
			int use_fd = fd;

			do_fixed = fixed;

			if (sqthread)
				use_fd = 0;
			if (fixed && (i & 1))
				do_fixed = 0;
			if (do_fixed) {
				io_uring_prep_write_fixed(sqe, use_fd, vecs[i].iov_base,
								vecs[i].iov_len,
								offset, i);
				sqe->cmd_op = NVME_URING_CMD_IO;
			} else if (nonvec) {
				io_uring_prep_write(sqe, use_fd, vecs[i].iov_base,
							vecs[i].iov_len, offset);
				sqe->cmd_op = NVME_URING_CMD_IO;
			} else {
				io_uring_prep_writev(sqe, use_fd, &vecs[i], 1,
								offset);
				sqe->cmd_op = NVME_URING_CMD_IO_VEC;
			}
		}
		sqe->opcode = IORING_OP_URING_CMD;
		sqe->user_data = ((uint64_t)offset << 32) | i;
		if (sqthread)
			sqe->flags |= IOSQE_FIXED_FILE;

		cmd = (struct nvme_uring_cmd *)sqe->cmd;
		memset(cmd, 0, sizeof(struct nvme_uring_cmd));

		cmd->opcode = read ? nvme_cmd_read : nvme_cmd_write;

		slba = offset >> lba_shift;
		nlb = (BS >> lba_shift) - 1;

		/* cdw10 and cdw11 represent starting lba */
		cmd->cdw10 = slba & 0xffffffff;
		cmd->cdw11 = slba >> 32;
		/* cdw12 represent number of lba's for read/write */
		cmd->cdw12 = nlb;
		if (do_fixed || nonvec) {
			cmd->addr = (__u64)(uintptr_t)vecs[i].iov_base;
			cmd->data_len = vecs[i].iov_len;
		} else {
			cmd->addr = (__u64)(uintptr_t)&vecs[i];
			cmd->data_len = 1;
		}
		cmd->nsid = nsid;

		offset += BS;
	}

	ret = io_uring_submit(ring);
	if (ret != BUFFERS) {
		fprintf(stderr, "submit got %d, wanted %d\n", ret, BUFFERS);
		goto err;
	}

	for (i = 0; i < BUFFERS; i++) {
		ret = io_uring_wait_cqe(ring, &cqe);
		if (ret) {
			fprintf(stderr, "wait_cqe=%d\n", ret);
			goto err;
		}
		if (cqe->res != 0) {
			if (!no_pt) {
				no_pt = 1;
				goto skip;
			}
			fprintf(stderr, "cqe res %d, wanted 0\n", cqe->res);
			goto err;
		}
		io_uring_cqe_seen(ring, cqe);
		if (read) {
			int index = cqe->user_data & 0xffffffff;
			void *buf = vecs[index].iov_base;
			off_t voff = cqe->user_data >> 32;

			if (verify_buf(tc, buf, voff))
				goto err;
		}
	}

	if (fixed) {
		ret = io_uring_unregister_buffers(ring);
		if (ret) {
			fprintf(stderr, "buffer unreg failed: %d\n", ret);
			goto err;
		}
	}
	if (sqthread) {
		ret = io_uring_unregister_files(ring);
		if (ret) {
			fprintf(stderr, "file unreg failed: %d\n", ret);
			goto err;
		}
	}

skip:
	close(fd);
	return 0;
err:
	if (fd != -1)
		close(fd);
	return 1;
}

static int test_io(const char *file, int tc, int read, int sqthread,
		   int fixed, int nonvec)
{
	struct io_uring ring;
	int ret, ring_flags = 0;

	ring_flags |= IORING_SETUP_SQE128;
	ring_flags |= IORING_SETUP_CQE32;

	if (sqthread)
		ring_flags |= IORING_SETUP_SQPOLL;

	ret = t_create_ring(64, &ring, ring_flags);
	if (ret == T_SETUP_SKIP)
		return 0;
	if (ret != T_SETUP_OK) {
		if (ret == -EINVAL) {
			no_pt = 1;
			return T_SETUP_SKIP;
		}
		fprintf(stderr, "ring create failed: %d\n", ret);
		return 1;
	}

	ret = __test_io(file, &ring, tc, read, sqthread, fixed, nonvec);
	io_uring_queue_exit(&ring);

	return ret;
}

/*
 * Send a passthrough command that nvme will fail during submission.
 * This comes handy for testing error handling.
 */
static int test_invalid_passthru_submit(const char *file)
{
	struct io_uring ring;
	int fd, ret, ring_flags, open_flags;
	struct io_uring_cqe *cqe;
	struct io_uring_sqe *sqe;
	struct nvme_uring_cmd *cmd;

	ring_flags = IORING_SETUP_CQE32 | IORING_SETUP_SQE128;

	ret = t_create_ring(1, &ring, ring_flags);
	if (ret != T_SETUP_OK) {
		fprintf(stderr, "ring create failed: %d\n", ret);
		return 1;
	}

	open_flags = O_RDONLY;
	fd = open(file, open_flags);
	if (fd < 0) {
		perror("file open");
		goto err;
	}

	sqe = io_uring_get_sqe(&ring);
	io_uring_prep_read(sqe, fd, vecs[0].iov_base, vecs[0].iov_len, 0);
	sqe->cmd_op = NVME_URING_CMD_IO;
	sqe->opcode = IORING_OP_URING_CMD;
	sqe->user_data = 1;
	cmd = (struct nvme_uring_cmd *)sqe->cmd;
	memset(cmd, 0, sizeof(struct nvme_uring_cmd));
	cmd->opcode = nvme_cmd_read;
	cmd->addr = (__u64)(uintptr_t)&vecs[0].iov_base;
	cmd->data_len = vecs[0].iov_len;
	/* populate wrong nsid to force failure */
	cmd->nsid = nsid + 1;

	ret = io_uring_submit(&ring);
	if (ret != 1) {
		fprintf(stderr, "submit got %d, wanted %d\n", ret, 1);
		goto err;
	}
	ret = io_uring_wait_cqe(&ring, &cqe);
	if (ret) {
		fprintf(stderr, "wait_cqe=%d\n", ret);
		goto err;
	}
	if (cqe->res == 0) {
		fprintf(stderr, "cqe res %d, wanted failure\n", cqe->res);
		goto err;
	}
	io_uring_cqe_seen(&ring, cqe);
	close(fd);
	io_uring_queue_exit(&ring);
	return 0;
err:
	if (fd != -1)
		close(fd);
	io_uring_queue_exit(&ring);
	return 1;
}

/*
 * if we are polling io_uring_submit needs to always enter the
 * kernel to fetch events
 */
static int test_io_uring_submit_enters(const char *file)
{
	struct io_uring ring;
	int fd, i, ret, ring_flags, open_flags;
	unsigned head;
	struct io_uring_cqe *cqe;
	struct nvme_uring_cmd *cmd;
	struct io_uring_sqe *sqe;

	ring_flags = IORING_SETUP_IOPOLL;
	ring_flags |= IORING_SETUP_SQE128;
	ring_flags |= IORING_SETUP_CQE32;

	ret = io_uring_queue_init(64, &ring, ring_flags);
	if (ret) {
		fprintf(stderr, "ring create failed: %d\n", ret);
		return 1;
	}

	open_flags = O_WRONLY;
	fd = open(file, open_flags);
	if (fd < 0) {
		perror("file open");
		goto err;
	}

	for (i = 0; i < BUFFERS; i++) {
		off_t offset = BS * (rand() % BUFFERS);
		__u64 slba;
		__u32 nlb;

		sqe = io_uring_get_sqe(&ring);
		io_uring_prep_readv(sqe, fd, &vecs[i], 1, offset);
		sqe->user_data = i;
		sqe->opcode = IORING_OP_URING_CMD;
		sqe->cmd_op = NVME_URING_CMD_IO;
		cmd = (struct nvme_uring_cmd *)sqe->cmd;
		memset(cmd, 0, sizeof(struct nvme_uring_cmd));

		slba = offset >> lba_shift;
		nlb = (BS >> lba_shift) - 1;

		cmd->opcode = nvme_cmd_read;
		cmd->cdw10 = slba & 0xffffffff;
		cmd->cdw11 = slba >> 32;
		cmd->cdw12 = nlb;
		cmd->addr = (__u64)(uintptr_t)&vecs[i];
		cmd->data_len = 1;
		cmd->nsid = nsid;
	}

	/* submit manually to avoid adding IORING_ENTER_GETEVENTS */
	ret = __sys_io_uring_enter(ring.ring_fd, __io_uring_flush_sq(&ring), 0,
						0, NULL);
	if (ret < 0)
		goto err;

	for (i = 0; i < 500; i++) {
		ret = io_uring_submit(&ring);
		if (ret != 0) {
			fprintf(stderr, "still had %d sqes to submit\n", ret);
			goto err;
		}

		io_uring_for_each_cqe(&ring, head, cqe) {
			if (cqe->res == -EOPNOTSUPP)
				fprintf(stdout, "Device doesn't support polled IO\n");
			goto ok;
		}
		usleep(10000);
	}
err:
	ret = 1;
	if (fd != -1)
		close(fd);

ok:
	io_uring_queue_exit(&ring);
	return ret;
}

int main(int argc, char *argv[])
{
	int i, ret;
	char *fname;

	if (argc < 2)
		return T_EXIT_SKIP;

	fname = argv[1];
	ret = nvme_get_info(fname);

	if (ret)
		return T_EXIT_SKIP;

	vecs = t_create_buffers(BUFFERS, BS);

	for (i = 0; i < 16; i++) {
		int read = (i & 1) != 0;
		int sqthread = (i & 2) != 0;
		int fixed = (i & 4) != 0;
		int nonvec = (i & 8) != 0;

		ret = test_io(fname, i, read, sqthread, fixed, nonvec);
		if (no_pt)
			break;
		if (ret) {
			fprintf(stderr, "test_io failed %d/%d/%d/%d\n",
				read, sqthread, fixed, nonvec);
			goto err;
		}
	}

	if (no_pt)
		return T_EXIT_SKIP;

	ret = test_io_uring_submit_enters(fname);
	if (ret) {
		fprintf(stderr, "test_io_uring_submit_enters failed\n");
		goto err;
	}

	ret = test_invalid_passthru_submit(fname);
	if (ret) {
		fprintf(stderr, "test_invalid_passthru_submit failed\n");
		goto err;
	}

	return T_EXIT_PASS;
err:
	return T_EXIT_FAIL;
}