From 357ca596841f07d10cc1cbdcd227fc0edb6550d8 Mon Sep 17 00:00:00 2001
From: Jens Axboe <axboe@kernel.dk>
Date: Tue, 8 Jan 2019 15:41:14 -0700
Subject: Add sample 'cp' program
Don't rely on this for anything, it's just a test case / demo.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---
test/io_uring-cp.c | 227 +++++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 227 insertions(+)
create mode 100644 test/io_uring-cp.c
diff --git a/test/io_uring-cp.c b/test/io_uring-cp.c
new file mode 100644
index 0000000..8fba13f
--- /dev/null
+++ b/test/io_uring-cp.c
@@ -0,0 +1,227 @@
+/*
+ * gcc -Wall -O2 -D_GNU_SOURCE -o io_uring-cp io_uring-cp.c -luring
+ */
+#include <stdio.h>
+#include <fcntl.h>
+#include <string.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <assert.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include "../src/liburing.h"
+
+#define QD 64
+#define BS 4096
+
+struct ring {
+ struct io_uring uring;
+ int fd;
+};
+
+static struct ring in_ring;
+static struct ring out_ring;
+static void *bufs[QD];
+
+static int setup_context(unsigned entries, struct ring *r, int offload)
+{
+ struct io_uring_params p;
+ int ring_fd;
+
+ memset(&p, 0, sizeof(p));
+ if (offload)
+ p.flags = IORING_SETUP_SQWQ;
+
+ ring_fd = io_uring_queue_init(entries, &p, NULL, &r->uring);
+ if (ring_fd < 0) {
+ fprintf(stderr, "queue_init: %s\n", strerror(-ring_fd));
+ return -1;
+ }
+
+ r->fd = ring_fd;
+ 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;
+ }
+
+ return -1;
+}
+
+static unsigned iocb_index(struct io_uring_iocb *iocb)
+{
+ return iocb - in_ring.uring.sq.iocbs;
+}
+
+static int queue_read(int fd, off_t size, off_t offset)
+{
+ struct io_uring_iocb *iocb;
+
+ iocb = io_uring_get_iocb(&in_ring.uring);
+ if (!iocb)
+ return 1;
+
+ iocb->opcode = IORING_OP_READ;
+ iocb->flags = 0;
+ iocb->ioprio = 0;
+ iocb->fd = fd;
+ iocb->off = offset;
+ iocb->addr = bufs[iocb_index(iocb)];
+ iocb->len = size;
+ return 0;
+}
+
+static int complete_writes(unsigned *writes)
+{
+ int ret, nr;
+
+ ret = io_uring_submit(out_ring.fd, &out_ring.uring);
+ if (ret < 0) {
+ fprintf(stderr, "io_uring_submit: %s\n", strerror(-ret));
+ return 1;
+ }
+
+ nr = ret;
+ while (nr) {
+ struct io_uring_event *ev = NULL;
+
+ ret = io_uring_wait_completion(out_ring.fd, &out_ring.uring, &ev);
+ if (ret < 0) {
+ fprintf(stderr, "io_uring_wait_completion: %s\n",
+ strerror(-ret));
+ return 1;
+ }
+ if (ev->res < 0) {
+ fprintf(stderr, "ev failed: %s\n", strerror(-ev->res));
+ return 1;
+ }
+ (*writes)--;
+ nr--;
+ }
+
+ return 0;
+}
+
+static void queue_write(int fd, off_t size, off_t offset, unsigned index)
+{
+ struct io_uring_iocb *iocb;
+
+ iocb = io_uring_get_iocb(&out_ring.uring);
+ iocb->opcode = IORING_OP_WRITE;
+ iocb->flags = 0;
+ iocb->ioprio = 0;
+ iocb->fd = fd;
+ iocb->off = offset;
+ iocb->addr = bufs[index];
+ iocb->len = size;
+}
+
+int main(int argc, char *argv[])
+{
+ struct io_uring_event *ev;
+ off_t read_left, write_left, offset;
+ int i, infd, outfd, ret;
+ unsigned reads, writes;
+
+ 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;
+ }
+
+ for (i = 0; i < QD; i++)
+ if (posix_memalign(&bufs[i], BS, BS))
+ return 1;
+
+ if (setup_context(QD, &in_ring, 1))
+ return 1;
+ if (setup_context(QD, &out_ring, 0))
+ return 1;
+ if (get_file_size(infd, &read_left))
+ return 1;
+
+ offset = 0;
+ writes = reads = 0;
+ write_left = read_left;
+ while (read_left || write_left) {
+ off_t this_size = read_left;
+ struct io_uring_iocb *iocb;
+
+ if (this_size > BS)
+ this_size = BS;
+ else if (!this_size)
+ goto skip_read;
+
+ /*
+ * Queue up as many reads as we can
+ */
+ while (read_left && !queue_read(infd, this_size, offset)) {
+ read_left -= this_size;
+ offset += this_size;
+ reads++;
+ }
+
+skip_read:
+ ret = io_uring_submit(in_ring.fd, &in_ring.uring);
+ if (ret < 0) {
+ fprintf(stderr, "io_uring_submit: %s\n", strerror(-ret));
+ break;
+ }
+
+ /*
+ * read queue full, get at least one completion and queue up
+ * a write
+ */
+ while (reads || write_left) {
+ if (reads)
+ ret = io_uring_wait_completion(in_ring.fd,
+ &in_ring.uring, &ev);
+ else
+ ret = io_uring_get_completion(in_ring.fd,
+ &in_ring.uring, &ev);
+ if (ret < 0) {
+ fprintf(stderr, "io_uring_get_completion: %s\n",
+ strerror(-ret));
+ return 1;
+ }
+ if (!ev)
+ break;
+ reads--;
+ if (ev->res < 0) {
+ fprintf(stderr, "ev failed: %s\n",
+ strerror(-ev->res));
+ return 1;
+ }
+ iocb = io_uring_iocb_from_ev(&in_ring.uring, ev);
+ queue_write(outfd, ev->res, iocb->off, ev->index);
+ write_left -= ev->res;
+ writes++;
+ };
+ if (complete_writes(&writes))
+ break;
+ };
+
+ close(infd);
+ close(outfd);
+ io_uring_queue_exit(in_ring.fd, &in_ring.uring);
+ io_uring_queue_exit(out_ring.fd, &out_ring.uring);
+ return 0;
+}
--
cgit