Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/tools/io_uring/io_uring-cp.c b/tools/io_uring/io_uring-cp.c
new file mode 100644
index 0000000..8146181
--- /dev/null
+++ b/tools/io_uring/io_uring-cp.c
@@ -0,0 +1,260 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Simple test program that demonstrates a file copy through io_uring. This
+ * uses the API exposed by liburing.
+ *
+ * Copyright (C) 2018-2019 Jens Axboe
+ */
+#include <stdio.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <assert.h>
+#include <errno.h>
+#include <inttypes.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+
+#include "liburing.h"
+
+#define QD 64
+#define BS (32*1024)
+
+static int infd, outfd;
+
+struct io_data {
+ int read;
+ off_t first_offset, offset;
+ size_t first_len;
+ struct iovec iov;
+};
+
+static int setup_context(unsigned entries, struct io_uring *ring)
+{
+ int ret;
+
+ ret = io_uring_queue_init(entries, ring, 0);
+ if (ret < 0) {
+ fprintf(stderr, "queue_init: %s\n", strerror(-ret));
+ return -1;
+ }
+
+ return 0;
+}
+
+static int get_file_size(int fd, off_t *size)
+{
+ struct stat st;
+
+ if (fstat(fd, &st) < 0)
+ return -1;
+ if (S_ISREG(st.st_mode)) {
+ *size = st.st_size;
+ return 0;
+ } else if (S_ISBLK(st.st_mode)) {
+ unsigned long long bytes;
+
+ if (ioctl(fd, BLKGETSIZE64, &bytes) != 0)
+ return -1;
+
+ *size = bytes;
+ return 0;
+ }
+
+ return -1;
+}
+
+static void queue_prepped(struct io_uring *ring, struct io_data *data)
+{
+ struct io_uring_sqe *sqe;
+
+ sqe = io_uring_get_sqe(ring);
+ assert(sqe);
+
+ if (data->read)
+ io_uring_prep_readv(sqe, infd, &data->iov, 1, data->offset);
+ else
+ io_uring_prep_writev(sqe, outfd, &data->iov, 1, data->offset);
+
+ io_uring_sqe_set_data(sqe, data);
+}
+
+static int queue_read(struct io_uring *ring, off_t size, off_t offset)
+{
+ struct io_uring_sqe *sqe;
+ struct io_data *data;
+
+ data = malloc(size + sizeof(*data));
+ if (!data)
+ return 1;
+
+ sqe = io_uring_get_sqe(ring);
+ if (!sqe) {
+ free(data);
+ return 1;
+ }
+
+ data->read = 1;
+ data->offset = data->first_offset = offset;
+
+ data->iov.iov_base = data + 1;
+ data->iov.iov_len = size;
+ data->first_len = size;
+
+ io_uring_prep_readv(sqe, infd, &data->iov, 1, offset);
+ io_uring_sqe_set_data(sqe, data);
+ return 0;
+}
+
+static void queue_write(struct io_uring *ring, struct io_data *data)
+{
+ data->read = 0;
+ data->offset = data->first_offset;
+
+ data->iov.iov_base = data + 1;
+ data->iov.iov_len = data->first_len;
+
+ queue_prepped(ring, data);
+ io_uring_submit(ring);
+}
+
+static int copy_file(struct io_uring *ring, off_t insize)
+{
+ unsigned long reads, writes;
+ struct io_uring_cqe *cqe;
+ off_t write_left, offset;
+ int ret;
+
+ write_left = insize;
+ writes = reads = offset = 0;
+
+ while (insize || write_left) {
+ unsigned long had_reads;
+ int got_comp;
+
+ /*
+ * Queue up as many reads as we can
+ */
+ had_reads = reads;
+ while (insize) {
+ off_t this_size = insize;
+
+ if (reads + writes >= QD)
+ break;
+ if (this_size > BS)
+ this_size = BS;
+ else if (!this_size)
+ break;
+
+ if (queue_read(ring, this_size, offset))
+ break;
+
+ insize -= this_size;
+ offset += this_size;
+ reads++;
+ }
+
+ if (had_reads != reads) {
+ ret = io_uring_submit(ring);
+ if (ret < 0) {
+ fprintf(stderr, "io_uring_submit: %s\n", strerror(-ret));
+ break;
+ }
+ }
+
+ /*
+ * Queue is full at this point. Find at least one completion.
+ */
+ got_comp = 0;
+ while (write_left) {
+ struct io_data *data;
+
+ if (!got_comp) {
+ ret = io_uring_wait_cqe(ring, &cqe);
+ got_comp = 1;
+ } else
+ ret = io_uring_peek_cqe(ring, &cqe);
+ if (ret < 0) {
+ fprintf(stderr, "io_uring_peek_cqe: %s\n",
+ strerror(-ret));
+ return 1;
+ }
+ if (!cqe)
+ break;
+
+ data = io_uring_cqe_get_data(cqe);
+ if (cqe->res < 0) {
+ if (cqe->res == -EAGAIN) {
+ queue_prepped(ring, data);
+ io_uring_cqe_seen(ring, cqe);
+ continue;
+ }
+ fprintf(stderr, "cqe failed: %s\n",
+ strerror(-cqe->res));
+ return 1;
+ } else if ((size_t) cqe->res != data->iov.iov_len) {
+ /* Short read/write, adjust and requeue */
+ data->iov.iov_base += cqe->res;
+ data->iov.iov_len -= cqe->res;
+ data->offset += cqe->res;
+ queue_prepped(ring, data);
+ io_uring_cqe_seen(ring, cqe);
+ continue;
+ }
+
+ /*
+ * All done. if write, nothing else to do. if read,
+ * queue up corresponding write.
+ */
+ if (data->read) {
+ queue_write(ring, data);
+ write_left -= data->first_len;
+ reads--;
+ writes++;
+ } else {
+ free(data);
+ writes--;
+ }
+ io_uring_cqe_seen(ring, cqe);
+ }
+ }
+
+ return 0;
+}
+
+int main(int argc, char *argv[])
+{
+ struct io_uring ring;
+ off_t insize;
+ int ret;
+
+ if (argc < 3) {
+ printf("%s: infile outfile\n", argv[0]);
+ return 1;
+ }
+
+ infd = open(argv[1], O_RDONLY);
+ if (infd < 0) {
+ perror("open infile");
+ return 1;
+ }
+ outfd = open(argv[2], O_WRONLY | O_CREAT | O_TRUNC, 0644);
+ if (outfd < 0) {
+ perror("open outfile");
+ return 1;
+ }
+
+ if (setup_context(QD, &ring))
+ return 1;
+ if (get_file_size(infd, &insize))
+ return 1;
+
+ ret = copy_file(&ring, insize);
+
+ close(infd);
+ close(outfd);
+ io_uring_queue_exit(&ring);
+ return ret;
+}