F: include/trace/events/io_uring.h
F: include/uapi/linux/io_uring.h
F: io_uring/
-F: tools/io_uring/
IPMI SUBSYSTEM
M: Corey Minyard <minyard@acm.org>
+++ /dev/null
-# SPDX-License-Identifier: GPL-2.0
-# Makefile for io_uring test tools
-CFLAGS += -Wall -Wextra -g -D_GNU_SOURCE
-LDLIBS += -lpthread
-
-all: io_uring-cp io_uring-bench
-%: %.c
- $(CC) $(CFLAGS) -o $@ $^
-
-io_uring-bench: syscall.o io_uring-bench.o
- $(CC) $(CFLAGS) -o $@ $^ $(LDLIBS)
-
-io_uring-cp: setup.o syscall.o queue.o
-
-clean:
- $(RM) io_uring-cp io_uring-bench *.o
-
-.PHONY: all clean
+++ /dev/null
-This directory includes a few programs that demonstrate how to use io_uring
-in an application. The examples are:
-
-io_uring-cp
- A very basic io_uring implementation of cp(1). It takes two
- arguments, copies the first argument to the second. This example
- is part of liburing, and hence uses the simplified liburing API
- for setting up an io_uring instance, submitting IO, completing IO,
- etc. The support functions in queue.c and setup.c are straight
- out of liburing.
-
-io_uring-bench
- Benchmark program that does random reads on a number of files. This
- app demonstrates the various features of io_uring, like fixed files,
- fixed buffers, and polled IO. There are options in the program to
- control which features to use. Arguments is the file (or files) that
- io_uring-bench should operate on. This uses the raw io_uring
- interface.
-
-liburing can be cloned with git here:
-
- git://git.kernel.dk/liburing
-
-and contains a number of unit tests as well for testing io_uring. It also
-comes with man pages for the three system calls.
-
-Fio includes an io_uring engine, you can clone fio here:
-
- git://git.kernel.dk/fio
+++ /dev/null
-#ifndef LIBURING_BARRIER_H
-#define LIBURING_BARRIER_H
-
-#if defined(__x86_64) || defined(__i386__)
-#define read_barrier() __asm__ __volatile__("":::"memory")
-#define write_barrier() __asm__ __volatile__("":::"memory")
-#else
-/*
- * Add arch appropriate definitions. Be safe and use full barriers for
- * archs we don't have support for.
- */
-#define read_barrier() __sync_synchronize()
-#define write_barrier() __sync_synchronize()
-#endif
-
-#endif
+++ /dev/null
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Simple benchmark program that uses the various features of io_uring
- * to provide fast random access to a device/file. It has various
- * options that are control how we use io_uring, see the OPTIONS section
- * below. This uses the raw io_uring interface.
- *
- * Copyright (C) 2018-2019 Jens Axboe
- */
-#include <stdio.h>
-#include <errno.h>
-#include <assert.h>
-#include <stdlib.h>
-#include <stddef.h>
-#include <signal.h>
-#include <inttypes.h>
-
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/ioctl.h>
-#include <sys/syscall.h>
-#include <sys/resource.h>
-#include <sys/mman.h>
-#include <sys/uio.h>
-#include <linux/fs.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <string.h>
-#include <pthread.h>
-#include <sched.h>
-
-#include "liburing.h"
-#include "barrier.h"
-
-#define min(a, b) ((a < b) ? (a) : (b))
-
-struct io_sq_ring {
- unsigned *head;
- unsigned *tail;
- unsigned *ring_mask;
- unsigned *ring_entries;
- unsigned *flags;
- unsigned *array;
-};
-
-struct io_cq_ring {
- unsigned *head;
- unsigned *tail;
- unsigned *ring_mask;
- unsigned *ring_entries;
- struct io_uring_cqe *cqes;
-};
-
-#define DEPTH 128
-
-#define BATCH_SUBMIT 32
-#define BATCH_COMPLETE 32
-
-#define BS 4096
-
-#define MAX_FDS 16
-
-static unsigned sq_ring_mask, cq_ring_mask;
-
-struct file {
- unsigned long max_blocks;
- unsigned pending_ios;
- int real_fd;
- int fixed_fd;
-};
-
-struct submitter {
- pthread_t thread;
- int ring_fd;
- struct drand48_data rand;
- struct io_sq_ring sq_ring;
- struct io_uring_sqe *sqes;
- struct iovec iovecs[DEPTH];
- struct io_cq_ring cq_ring;
- int inflight;
- unsigned long reaps;
- unsigned long done;
- unsigned long calls;
- volatile int finish;
-
- __s32 *fds;
-
- struct file files[MAX_FDS];
- unsigned nr_files;
- unsigned cur_file;
-};
-
-static struct submitter submitters[1];
-static volatile int finish;
-
-/*
- * OPTIONS: Set these to test the various features of io_uring.
- */
-static int polled = 1; /* use IO polling */
-static int fixedbufs = 1; /* use fixed user buffers */
-static int register_files = 1; /* use fixed files */
-static int buffered = 0; /* use buffered IO, not O_DIRECT */
-static int sq_thread_poll = 0; /* use kernel submission/poller thread */
-static int sq_thread_cpu = -1; /* pin above thread to this CPU */
-static int do_nop = 0; /* no-op SQ ring commands */
-
-static int io_uring_register_buffers(struct submitter *s)
-{
- if (do_nop)
- return 0;
-
- return io_uring_register(s->ring_fd, IORING_REGISTER_BUFFERS, s->iovecs,
- DEPTH);
-}
-
-static int io_uring_register_files(struct submitter *s)
-{
- unsigned i;
-
- if (do_nop)
- return 0;
-
- s->fds = calloc(s->nr_files, sizeof(__s32));
- for (i = 0; i < s->nr_files; i++) {
- s->fds[i] = s->files[i].real_fd;
- s->files[i].fixed_fd = i;
- }
-
- return io_uring_register(s->ring_fd, IORING_REGISTER_FILES, s->fds,
- s->nr_files);
-}
-
-static int lk_gettid(void)
-{
- return syscall(__NR_gettid);
-}
-
-static unsigned file_depth(struct submitter *s)
-{
- return (DEPTH + s->nr_files - 1) / s->nr_files;
-}
-
-static void init_io(struct submitter *s, unsigned index)
-{
- struct io_uring_sqe *sqe = &s->sqes[index];
- unsigned long offset;
- struct file *f;
- long r;
-
- if (do_nop) {
- sqe->opcode = IORING_OP_NOP;
- return;
- }
-
- if (s->nr_files == 1) {
- f = &s->files[0];
- } else {
- f = &s->files[s->cur_file];
- if (f->pending_ios >= file_depth(s)) {
- s->cur_file++;
- if (s->cur_file == s->nr_files)
- s->cur_file = 0;
- f = &s->files[s->cur_file];
- }
- }
- f->pending_ios++;
-
- lrand48_r(&s->rand, &r);
- offset = (r % (f->max_blocks - 1)) * BS;
-
- if (register_files) {
- sqe->flags = IOSQE_FIXED_FILE;
- sqe->fd = f->fixed_fd;
- } else {
- sqe->flags = 0;
- sqe->fd = f->real_fd;
- }
- if (fixedbufs) {
- sqe->opcode = IORING_OP_READ_FIXED;
- sqe->addr = (unsigned long) s->iovecs[index].iov_base;
- sqe->len = BS;
- sqe->buf_index = index;
- } else {
- sqe->opcode = IORING_OP_READV;
- sqe->addr = (unsigned long) &s->iovecs[index];
- sqe->len = 1;
- sqe->buf_index = 0;
- }
- sqe->ioprio = 0;
- sqe->off = offset;
- sqe->user_data = (unsigned long) f;
-}
-
-static int prep_more_ios(struct submitter *s, unsigned max_ios)
-{
- struct io_sq_ring *ring = &s->sq_ring;
- unsigned index, tail, next_tail, prepped = 0;
-
- next_tail = tail = *ring->tail;
- do {
- next_tail++;
- read_barrier();
- if (next_tail == *ring->head)
- break;
-
- index = tail & sq_ring_mask;
- init_io(s, index);
- ring->array[index] = index;
- prepped++;
- tail = next_tail;
- } while (prepped < max_ios);
-
- if (*ring->tail != tail) {
- /* order tail store with writes to sqes above */
- write_barrier();
- *ring->tail = tail;
- write_barrier();
- }
- return prepped;
-}
-
-static int get_file_size(struct file *f)
-{
- struct stat st;
-
- if (fstat(f->real_fd, &st) < 0)
- return -1;
- if (S_ISBLK(st.st_mode)) {
- unsigned long long bytes;
-
- if (ioctl(f->real_fd, BLKGETSIZE64, &bytes) != 0)
- return -1;
-
- f->max_blocks = bytes / BS;
- return 0;
- } else if (S_ISREG(st.st_mode)) {
- f->max_blocks = st.st_size / BS;
- return 0;
- }
-
- return -1;
-}
-
-static int reap_events(struct submitter *s)
-{
- struct io_cq_ring *ring = &s->cq_ring;
- struct io_uring_cqe *cqe;
- unsigned head, reaped = 0;
-
- head = *ring->head;
- do {
- struct file *f;
-
- read_barrier();
- if (head == *ring->tail)
- break;
- cqe = &ring->cqes[head & cq_ring_mask];
- if (!do_nop) {
- f = (struct file *) (uintptr_t) cqe->user_data;
- f->pending_ios--;
- if (cqe->res != BS) {
- printf("io: unexpected ret=%d\n", cqe->res);
- if (polled && cqe->res == -EOPNOTSUPP)
- printf("Your filesystem doesn't support poll\n");
- return -1;
- }
- }
- reaped++;
- head++;
- } while (1);
-
- s->inflight -= reaped;
- *ring->head = head;
- write_barrier();
- return reaped;
-}
-
-static void *submitter_fn(void *data)
-{
- struct submitter *s = data;
- struct io_sq_ring *ring = &s->sq_ring;
- int ret, prepped;
-
- printf("submitter=%d\n", lk_gettid());
-
- srand48_r(pthread_self(), &s->rand);
-
- prepped = 0;
- do {
- int to_wait, to_submit, this_reap, to_prep;
-
- if (!prepped && s->inflight < DEPTH) {
- to_prep = min(DEPTH - s->inflight, BATCH_SUBMIT);
- prepped = prep_more_ios(s, to_prep);
- }
- s->inflight += prepped;
-submit_more:
- to_submit = prepped;
-submit:
- if (to_submit && (s->inflight + to_submit <= DEPTH))
- to_wait = 0;
- else
- to_wait = min(s->inflight + to_submit, BATCH_COMPLETE);
-
- /*
- * Only need to call io_uring_enter if we're not using SQ thread
- * poll, or if IORING_SQ_NEED_WAKEUP is set.
- */
- if (!sq_thread_poll || (*ring->flags & IORING_SQ_NEED_WAKEUP)) {
- unsigned flags = 0;
-
- if (to_wait)
- flags = IORING_ENTER_GETEVENTS;
- if ((*ring->flags & IORING_SQ_NEED_WAKEUP))
- flags |= IORING_ENTER_SQ_WAKEUP;
- ret = io_uring_enter(s->ring_fd, to_submit, to_wait,
- flags, NULL);
- s->calls++;
- }
-
- /*
- * For non SQ thread poll, we already got the events we needed
- * through the io_uring_enter() above. For SQ thread poll, we
- * need to loop here until we find enough events.
- */
- this_reap = 0;
- do {
- int r;
- r = reap_events(s);
- if (r == -1) {
- s->finish = 1;
- break;
- } else if (r > 0)
- this_reap += r;
- } while (sq_thread_poll && this_reap < to_wait);
- s->reaps += this_reap;
-
- if (ret >= 0) {
- if (!ret) {
- to_submit = 0;
- if (s->inflight)
- goto submit;
- continue;
- } else if (ret < to_submit) {
- int diff = to_submit - ret;
-
- s->done += ret;
- prepped -= diff;
- goto submit_more;
- }
- s->done += ret;
- prepped = 0;
- continue;
- } else if (ret < 0) {
- if (errno == EAGAIN) {
- if (s->finish)
- break;
- if (this_reap)
- goto submit;
- to_submit = 0;
- goto submit;
- }
- printf("io_submit: %s\n", strerror(errno));
- break;
- }
- } while (!s->finish);
-
- finish = 1;
- return NULL;
-}
-
-static void sig_int(int sig)
-{
- printf("Exiting on signal %d\n", sig);
- submitters[0].finish = 1;
- finish = 1;
-}
-
-static void arm_sig_int(void)
-{
- struct sigaction act;
-
- memset(&act, 0, sizeof(act));
- act.sa_handler = sig_int;
- act.sa_flags = SA_RESTART;
- sigaction(SIGINT, &act, NULL);
-}
-
-static int setup_ring(struct submitter *s)
-{
- struct io_sq_ring *sring = &s->sq_ring;
- struct io_cq_ring *cring = &s->cq_ring;
- struct io_uring_params p;
- int ret, fd;
- void *ptr;
-
- memset(&p, 0, sizeof(p));
-
- if (polled && !do_nop)
- p.flags |= IORING_SETUP_IOPOLL;
- if (sq_thread_poll) {
- p.flags |= IORING_SETUP_SQPOLL;
- if (sq_thread_cpu != -1) {
- p.flags |= IORING_SETUP_SQ_AFF;
- p.sq_thread_cpu = sq_thread_cpu;
- }
- }
-
- fd = io_uring_setup(DEPTH, &p);
- if (fd < 0) {
- perror("io_uring_setup");
- return 1;
- }
- s->ring_fd = fd;
-
- if (fixedbufs) {
- ret = io_uring_register_buffers(s);
- if (ret < 0) {
- perror("io_uring_register_buffers");
- return 1;
- }
- }
-
- if (register_files) {
- ret = io_uring_register_files(s);
- if (ret < 0) {
- perror("io_uring_register_files");
- return 1;
- }
- }
-
- ptr = mmap(0, p.sq_off.array + p.sq_entries * sizeof(__u32),
- PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
- IORING_OFF_SQ_RING);
- printf("sq_ring ptr = 0x%p\n", ptr);
- sring->head = ptr + p.sq_off.head;
- sring->tail = ptr + p.sq_off.tail;
- sring->ring_mask = ptr + p.sq_off.ring_mask;
- sring->ring_entries = ptr + p.sq_off.ring_entries;
- sring->flags = ptr + p.sq_off.flags;
- sring->array = ptr + p.sq_off.array;
- sq_ring_mask = *sring->ring_mask;
-
- s->sqes = mmap(0, p.sq_entries * sizeof(struct io_uring_sqe),
- PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
- IORING_OFF_SQES);
- printf("sqes ptr = 0x%p\n", s->sqes);
-
- ptr = mmap(0, p.cq_off.cqes + p.cq_entries * sizeof(struct io_uring_cqe),
- PROT_READ | PROT_WRITE, MAP_SHARED | MAP_POPULATE, fd,
- IORING_OFF_CQ_RING);
- printf("cq_ring ptr = 0x%p\n", ptr);
- cring->head = ptr + p.cq_off.head;
- cring->tail = ptr + p.cq_off.tail;
- cring->ring_mask = ptr + p.cq_off.ring_mask;
- cring->ring_entries = ptr + p.cq_off.ring_entries;
- cring->cqes = ptr + p.cq_off.cqes;
- cq_ring_mask = *cring->ring_mask;
- return 0;
-}
-
-static void file_depths(char *buf)
-{
- struct submitter *s = &submitters[0];
- unsigned i;
- char *p;
-
- buf[0] = '\0';
- p = buf;
- for (i = 0; i < s->nr_files; i++) {
- struct file *f = &s->files[i];
-
- if (i + 1 == s->nr_files)
- p += sprintf(p, "%d", f->pending_ios);
- else
- p += sprintf(p, "%d, ", f->pending_ios);
- }
-}
-
-int main(int argc, char *argv[])
-{
- struct submitter *s = &submitters[0];
- unsigned long done, calls, reap;
- int err, i, flags, fd;
- char *fdepths;
- void *ret;
-
- if (!do_nop && argc < 2) {
- printf("%s: filename\n", argv[0]);
- return 1;
- }
-
- flags = O_RDONLY | O_NOATIME;
- if (!buffered)
- flags |= O_DIRECT;
-
- i = 1;
- while (!do_nop && i < argc) {
- struct file *f;
-
- if (s->nr_files == MAX_FDS) {
- printf("Max number of files (%d) reached\n", MAX_FDS);
- break;
- }
- fd = open(argv[i], flags);
- if (fd < 0) {
- perror("open");
- return 1;
- }
-
- f = &s->files[s->nr_files];
- f->real_fd = fd;
- if (get_file_size(f)) {
- printf("failed getting size of device/file\n");
- return 1;
- }
- if (f->max_blocks <= 1) {
- printf("Zero file/device size?\n");
- return 1;
- }
- f->max_blocks--;
-
- printf("Added file %s\n", argv[i]);
- s->nr_files++;
- i++;
- }
-
- if (fixedbufs) {
- struct rlimit rlim;
-
- rlim.rlim_cur = RLIM_INFINITY;
- rlim.rlim_max = RLIM_INFINITY;
- if (setrlimit(RLIMIT_MEMLOCK, &rlim) < 0) {
- perror("setrlimit");
- return 1;
- }
- }
-
- arm_sig_int();
-
- for (i = 0; i < DEPTH; i++) {
- void *buf;
-
- if (posix_memalign(&buf, BS, BS)) {
- printf("failed alloc\n");
- return 1;
- }
- s->iovecs[i].iov_base = buf;
- s->iovecs[i].iov_len = BS;
- }
-
- err = setup_ring(s);
- if (err) {
- printf("ring setup failed: %s, %d\n", strerror(errno), err);
- return 1;
- }
- printf("polled=%d, fixedbufs=%d, buffered=%d", polled, fixedbufs, buffered);
- printf(" QD=%d, sq_ring=%d, cq_ring=%d\n", DEPTH, *s->sq_ring.ring_entries, *s->cq_ring.ring_entries);
-
- pthread_create(&s->thread, NULL, submitter_fn, s);
-
- fdepths = malloc(8 * s->nr_files);
- reap = calls = done = 0;
- do {
- unsigned long this_done = 0;
- unsigned long this_reap = 0;
- unsigned long this_call = 0;
- unsigned long rpc = 0, ipc = 0;
-
- sleep(1);
- this_done += s->done;
- this_call += s->calls;
- this_reap += s->reaps;
- if (this_call - calls) {
- rpc = (this_done - done) / (this_call - calls);
- ipc = (this_reap - reap) / (this_call - calls);
- } else
- rpc = ipc = -1;
- file_depths(fdepths);
- printf("IOPS=%lu, IOS/call=%ld/%ld, inflight=%u (%s)\n",
- this_done - done, rpc, ipc, s->inflight,
- fdepths);
- done = this_done;
- calls = this_call;
- reap = this_reap;
- } while (!finish);
-
- pthread_join(s->thread, &ret);
- close(s->ring_fd);
- free(fdepths);
- return 0;
-}
+++ /dev/null
-// 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) {
- int had_reads, 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 == -EAGAIN) {
- cqe = NULL;
- ret = 0;
- }
- }
- 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 (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);
- }
- }
-
- /* wait out pending writes */
- while (writes) {
- struct io_data *data;
-
- ret = io_uring_wait_cqe(ring, &cqe);
- if (ret) {
- fprintf(stderr, "wait_cqe=%d\n", ret);
- return 1;
- }
- if (cqe->res < 0) {
- fprintf(stderr, "write res=%d\n", cqe->res);
- return 1;
- }
- data = io_uring_cqe_get_data(cqe);
- 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;
-}
+++ /dev/null
-#ifndef LIB_URING_H
-#define LIB_URING_H
-
-#ifdef __cplusplus
-extern "C" {
-#endif
-
-#include <sys/uio.h>
-#include <signal.h>
-#include <string.h>
-#include "../../include/uapi/linux/io_uring.h"
-#include <inttypes.h>
-#include <linux/swab.h>
-#include "barrier.h"
-
-/*
- * Library interface to io_uring
- */
-struct io_uring_sq {
- unsigned *khead;
- unsigned *ktail;
- unsigned *kring_mask;
- unsigned *kring_entries;
- unsigned *kflags;
- unsigned *kdropped;
- unsigned *array;
- struct io_uring_sqe *sqes;
-
- unsigned sqe_head;
- unsigned sqe_tail;
-
- size_t ring_sz;
-};
-
-struct io_uring_cq {
- unsigned *khead;
- unsigned *ktail;
- unsigned *kring_mask;
- unsigned *kring_entries;
- unsigned *koverflow;
- struct io_uring_cqe *cqes;
-
- size_t ring_sz;
-};
-
-struct io_uring {
- struct io_uring_sq sq;
- struct io_uring_cq cq;
- int ring_fd;
-};
-
-/*
- * System calls
- */
-extern int io_uring_setup(unsigned entries, struct io_uring_params *p);
-extern int io_uring_enter(int fd, unsigned to_submit,
- unsigned min_complete, unsigned flags, sigset_t *sig);
-extern int io_uring_register(int fd, unsigned int opcode, void *arg,
- unsigned int nr_args);
-
-/*
- * Library interface
- */
-extern int io_uring_queue_init(unsigned entries, struct io_uring *ring,
- unsigned flags);
-extern int io_uring_queue_mmap(int fd, struct io_uring_params *p,
- struct io_uring *ring);
-extern void io_uring_queue_exit(struct io_uring *ring);
-extern int io_uring_peek_cqe(struct io_uring *ring,
- struct io_uring_cqe **cqe_ptr);
-extern int io_uring_wait_cqe(struct io_uring *ring,
- struct io_uring_cqe **cqe_ptr);
-extern int io_uring_submit(struct io_uring *ring);
-extern struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring);
-
-/*
- * Must be called after io_uring_{peek,wait}_cqe() after the cqe has
- * been processed by the application.
- */
-static inline void io_uring_cqe_seen(struct io_uring *ring,
- struct io_uring_cqe *cqe)
-{
- if (cqe) {
- struct io_uring_cq *cq = &ring->cq;
-
- (*cq->khead)++;
- /*
- * Ensure that the kernel sees our new head, the kernel has
- * the matching read barrier.
- */
- write_barrier();
- }
-}
-
-/*
- * Command prep helpers
- */
-static inline void io_uring_sqe_set_data(struct io_uring_sqe *sqe, void *data)
-{
- sqe->user_data = (unsigned long) data;
-}
-
-static inline void *io_uring_cqe_get_data(struct io_uring_cqe *cqe)
-{
- return (void *) (uintptr_t) cqe->user_data;
-}
-
-static inline void io_uring_prep_rw(int op, struct io_uring_sqe *sqe, int fd,
- const void *addr, unsigned len,
- off_t offset)
-{
- memset(sqe, 0, sizeof(*sqe));
- sqe->opcode = op;
- sqe->fd = fd;
- sqe->off = offset;
- sqe->addr = (unsigned long) addr;
- sqe->len = len;
-}
-
-static inline void io_uring_prep_readv(struct io_uring_sqe *sqe, int fd,
- const struct iovec *iovecs,
- unsigned nr_vecs, off_t offset)
-{
- io_uring_prep_rw(IORING_OP_READV, sqe, fd, iovecs, nr_vecs, offset);
-}
-
-static inline void io_uring_prep_read_fixed(struct io_uring_sqe *sqe, int fd,
- void *buf, unsigned nbytes,
- off_t offset)
-{
- io_uring_prep_rw(IORING_OP_READ_FIXED, sqe, fd, buf, nbytes, offset);
-}
-
-static inline void io_uring_prep_writev(struct io_uring_sqe *sqe, int fd,
- const struct iovec *iovecs,
- unsigned nr_vecs, off_t offset)
-{
- io_uring_prep_rw(IORING_OP_WRITEV, sqe, fd, iovecs, nr_vecs, offset);
-}
-
-static inline void io_uring_prep_write_fixed(struct io_uring_sqe *sqe, int fd,
- const void *buf, unsigned nbytes,
- off_t offset)
-{
- io_uring_prep_rw(IORING_OP_WRITE_FIXED, sqe, fd, buf, nbytes, offset);
-}
-
-static inline void io_uring_prep_poll_add(struct io_uring_sqe *sqe, int fd,
- unsigned poll_mask)
-{
- memset(sqe, 0, sizeof(*sqe));
- sqe->opcode = IORING_OP_POLL_ADD;
- sqe->fd = fd;
-#if __BYTE_ORDER == __BIG_ENDIAN
- poll_mask = __swahw32(poll_mask);
-#endif
- sqe->poll_events = poll_mask;
-}
-
-static inline void io_uring_prep_poll_remove(struct io_uring_sqe *sqe,
- void *user_data)
-{
- memset(sqe, 0, sizeof(*sqe));
- sqe->opcode = IORING_OP_POLL_REMOVE;
- sqe->addr = (unsigned long) user_data;
-}
-
-static inline void io_uring_prep_fsync(struct io_uring_sqe *sqe, int fd,
- unsigned fsync_flags)
-{
- memset(sqe, 0, sizeof(*sqe));
- sqe->opcode = IORING_OP_FSYNC;
- sqe->fd = fd;
- sqe->fsync_flags = fsync_flags;
-}
-
-static inline void io_uring_prep_nop(struct io_uring_sqe *sqe)
-{
- memset(sqe, 0, sizeof(*sqe));
- sqe->opcode = IORING_OP_NOP;
-}
-
-#ifdef __cplusplus
-}
-#endif
-
-#endif
+++ /dev/null
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/mman.h>
-#include <unistd.h>
-#include <errno.h>
-#include <string.h>
-
-#include "liburing.h"
-#include "barrier.h"
-
-static int __io_uring_get_cqe(struct io_uring *ring,
- struct io_uring_cqe **cqe_ptr, int wait)
-{
- struct io_uring_cq *cq = &ring->cq;
- const unsigned mask = *cq->kring_mask;
- unsigned head;
- int ret;
-
- *cqe_ptr = NULL;
- head = *cq->khead;
- do {
- /*
- * It's necessary to use a read_barrier() before reading
- * the CQ tail, since the kernel updates it locklessly. The
- * kernel has the matching store barrier for the update. The
- * kernel also ensures that previous stores to CQEs are ordered
- * with the tail update.
- */
- read_barrier();
- if (head != *cq->ktail) {
- *cqe_ptr = &cq->cqes[head & mask];
- break;
- }
- if (!wait)
- break;
- ret = io_uring_enter(ring->ring_fd, 0, 1,
- IORING_ENTER_GETEVENTS, NULL);
- if (ret < 0)
- return -errno;
- } while (1);
-
- return 0;
-}
-
-/*
- * Return an IO completion, if one is readily available. Returns 0 with
- * cqe_ptr filled in on success, -errno on failure.
- */
-int io_uring_peek_cqe(struct io_uring *ring, struct io_uring_cqe **cqe_ptr)
-{
- return __io_uring_get_cqe(ring, cqe_ptr, 0);
-}
-
-/*
- * Return an IO completion, waiting for it if necessary. Returns 0 with
- * cqe_ptr filled in on success, -errno on failure.
- */
-int io_uring_wait_cqe(struct io_uring *ring, struct io_uring_cqe **cqe_ptr)
-{
- return __io_uring_get_cqe(ring, cqe_ptr, 1);
-}
-
-/*
- * Submit sqes acquired from io_uring_get_sqe() to the kernel.
- *
- * Returns number of sqes submitted
- */
-int io_uring_submit(struct io_uring *ring)
-{
- struct io_uring_sq *sq = &ring->sq;
- const unsigned mask = *sq->kring_mask;
- unsigned ktail, ktail_next, submitted, to_submit;
- int ret;
-
- /*
- * If we have pending IO in the kring, submit it first. We need a
- * read barrier here to match the kernels store barrier when updating
- * the SQ head.
- */
- read_barrier();
- if (*sq->khead != *sq->ktail) {
- submitted = *sq->kring_entries;
- goto submit;
- }
-
- if (sq->sqe_head == sq->sqe_tail)
- return 0;
-
- /*
- * Fill in sqes that we have queued up, adding them to the kernel ring
- */
- submitted = 0;
- ktail = ktail_next = *sq->ktail;
- to_submit = sq->sqe_tail - sq->sqe_head;
- while (to_submit--) {
- ktail_next++;
- read_barrier();
-
- sq->array[ktail & mask] = sq->sqe_head & mask;
- ktail = ktail_next;
-
- sq->sqe_head++;
- submitted++;
- }
-
- if (!submitted)
- return 0;
-
- if (*sq->ktail != ktail) {
- /*
- * First write barrier ensures that the SQE stores are updated
- * with the tail update. This is needed so that the kernel
- * will never see a tail update without the preceeding sQE
- * stores being done.
- */
- write_barrier();
- *sq->ktail = ktail;
- /*
- * The kernel has the matching read barrier for reading the
- * SQ tail.
- */
- write_barrier();
- }
-
-submit:
- ret = io_uring_enter(ring->ring_fd, submitted, 0,
- IORING_ENTER_GETEVENTS, NULL);
- if (ret < 0)
- return -errno;
-
- return ret;
-}
-
-/*
- * Return an sqe to fill. Application must later call io_uring_submit()
- * when it's ready to tell the kernel about it. The caller may call this
- * function multiple times before calling io_uring_submit().
- *
- * Returns a vacant sqe, or NULL if we're full.
- */
-struct io_uring_sqe *io_uring_get_sqe(struct io_uring *ring)
-{
- struct io_uring_sq *sq = &ring->sq;
- unsigned next = sq->sqe_tail + 1;
- struct io_uring_sqe *sqe;
-
- /*
- * All sqes are used
- */
- if (next - sq->sqe_head > *sq->kring_entries)
- return NULL;
-
- sqe = &sq->sqes[sq->sqe_tail & *sq->kring_mask];
- sq->sqe_tail = next;
- return sqe;
-}
+++ /dev/null
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <sys/mman.h>
-#include <unistd.h>
-#include <errno.h>
-#include <string.h>
-
-#include "liburing.h"
-
-static int io_uring_mmap(int fd, struct io_uring_params *p,
- struct io_uring_sq *sq, struct io_uring_cq *cq)
-{
- size_t size;
- void *ptr;
- int ret;
-
- sq->ring_sz = p->sq_off.array + p->sq_entries * sizeof(unsigned);
- ptr = mmap(0, sq->ring_sz, PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_SQ_RING);
- if (ptr == MAP_FAILED)
- return -errno;
- sq->khead = ptr + p->sq_off.head;
- sq->ktail = ptr + p->sq_off.tail;
- sq->kring_mask = ptr + p->sq_off.ring_mask;
- sq->kring_entries = ptr + p->sq_off.ring_entries;
- sq->kflags = ptr + p->sq_off.flags;
- sq->kdropped = ptr + p->sq_off.dropped;
- sq->array = ptr + p->sq_off.array;
-
- size = p->sq_entries * sizeof(struct io_uring_sqe);
- sq->sqes = mmap(0, size, PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_POPULATE, fd,
- IORING_OFF_SQES);
- if (sq->sqes == MAP_FAILED) {
- ret = -errno;
-err:
- munmap(sq->khead, sq->ring_sz);
- return ret;
- }
-
- cq->ring_sz = p->cq_off.cqes + p->cq_entries * sizeof(struct io_uring_cqe);
- ptr = mmap(0, cq->ring_sz, PROT_READ | PROT_WRITE,
- MAP_SHARED | MAP_POPULATE, fd, IORING_OFF_CQ_RING);
- if (ptr == MAP_FAILED) {
- ret = -errno;
- munmap(sq->sqes, p->sq_entries * sizeof(struct io_uring_sqe));
- goto err;
- }
- cq->khead = ptr + p->cq_off.head;
- cq->ktail = ptr + p->cq_off.tail;
- cq->kring_mask = ptr + p->cq_off.ring_mask;
- cq->kring_entries = ptr + p->cq_off.ring_entries;
- cq->koverflow = ptr + p->cq_off.overflow;
- cq->cqes = ptr + p->cq_off.cqes;
- return 0;
-}
-
-/*
- * For users that want to specify sq_thread_cpu or sq_thread_idle, this
- * interface is a convenient helper for mmap()ing the rings.
- * Returns -1 on error, or zero on success. On success, 'ring'
- * contains the necessary information to read/write to the rings.
- */
-int io_uring_queue_mmap(int fd, struct io_uring_params *p, struct io_uring *ring)
-{
- int ret;
-
- memset(ring, 0, sizeof(*ring));
- ret = io_uring_mmap(fd, p, &ring->sq, &ring->cq);
- if (!ret)
- ring->ring_fd = fd;
- return ret;
-}
-
-/*
- * Returns -1 on error, or zero on success. On success, 'ring'
- * contains the necessary information to read/write to the rings.
- */
-int io_uring_queue_init(unsigned entries, struct io_uring *ring, unsigned flags)
-{
- struct io_uring_params p;
- int fd, ret;
-
- memset(&p, 0, sizeof(p));
- p.flags = flags;
-
- fd = io_uring_setup(entries, &p);
- if (fd < 0)
- return fd;
-
- ret = io_uring_queue_mmap(fd, &p, ring);
- if (ret)
- close(fd);
-
- return ret;
-}
-
-void io_uring_queue_exit(struct io_uring *ring)
-{
- struct io_uring_sq *sq = &ring->sq;
- struct io_uring_cq *cq = &ring->cq;
-
- munmap(sq->sqes, *sq->kring_entries * sizeof(struct io_uring_sqe));
- munmap(sq->khead, sq->ring_sz);
- munmap(cq->khead, cq->ring_sz);
- close(ring->ring_fd);
-}
+++ /dev/null
-/*
- * Will go away once libc support is there
- */
-#include <unistd.h>
-#include <sys/syscall.h>
-#include <sys/uio.h>
-#include <signal.h>
-#include "liburing.h"
-
-#ifdef __alpha__
-/*
- * alpha is the only exception, all other architectures
- * have common numbers for new system calls.
- */
-# ifndef __NR_io_uring_setup
-# define __NR_io_uring_setup 535
-# endif
-# ifndef __NR_io_uring_enter
-# define __NR_io_uring_enter 536
-# endif
-# ifndef __NR_io_uring_register
-# define __NR_io_uring_register 537
-# endif
-#else /* !__alpha__ */
-# ifndef __NR_io_uring_setup
-# define __NR_io_uring_setup 425
-# endif
-# ifndef __NR_io_uring_enter
-# define __NR_io_uring_enter 426
-# endif
-# ifndef __NR_io_uring_register
-# define __NR_io_uring_register 427
-# endif
-#endif
-
-int io_uring_register(int fd, unsigned int opcode, void *arg,
- unsigned int nr_args)
-{
- return syscall(__NR_io_uring_register, fd, opcode, arg, nr_args);
-}
-
-int io_uring_setup(unsigned int entries, struct io_uring_params *p)
-{
- return syscall(__NR_io_uring_setup, entries, p);
-}
-
-int io_uring_enter(int fd, unsigned int to_submit, unsigned int min_complete,
- unsigned int flags, sigset_t *sig)
-{
- return syscall(__NR_io_uring_enter, fd, to_submit, min_complete,
- flags, sig, _NSIG / 8);
-}
projects / platform / kernel / linux-starfive.git / commitdiff