On Mon, Sep 02, 2019 at 09:56:07AM -0700, Darrick J. Wong wrote: > On Mon, Sep 02, 2019 at 10:20:52AM +0800, Zorro Lang wrote: > > On Thu, Aug 29, 2019 at 05:44:07PM -0700, Darrick J. Wong wrote: > > > From: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > > > > > > Andreas Grünbacher reports that on the two filesystems that support > > > iomap directio, it's possible for splice() to return -EAGAIN (instead of > > > a short splice) if the pipe being written to has less space available in > > > its pipe buffers than the length supplied by the calling process. > > > > > > This is a regression test to check for correct operation. > > > > > > XXX Andreas: Since you wrote the C reproducer, can you send me the > > > proper copyright and author attribution statement for the C program? > > > > > > Signed-off-by: Darrick J. Wong <darrick.wong@xxxxxxxxxx> > > > --- > > > > Hi Darrick, > > > > I tried to add a splice_f operation into xfs_io long time ago: > > https://marc.info/?l=linux-xfs&m=155828702128047&w=2 > > > > For we can easily write more splice related test case later, I'd like to have > > a xfs_io to help that (if it can). Would you like to help to review that patch, > > if it can match your requirement to write this case? Or it can be improved to > > cover more testing conditions? I'm really appreciate that:) > > Yeah, I'll try to have a look this week. Thanks so much, I wrote this patch with 'fsstress supports splice' together, when we found a XFS regression bug by splice operation. But this xfs_io command doesn't have a specified usage to reproduce a bug. So if it can be improved to be used to cover the case which you just wrote (about splice), that might be better I think. Thanks, Zorro > > (FWIW I think Eric is backed up with dozens of xfsprogs patches...) > > --D > > > Thanks, > > Zorro > > > > > .gitignore | 1 > > > src/Makefile | 2 - > > > src/splice-test.c | 173 +++++++++++++++++++++++++++++++++++++++++++++++++ > > > tests/generic/720 | 41 ++++++++++++ > > > tests/generic/720.out | 7 ++ > > > tests/generic/group | 1 > > > 6 files changed, 224 insertions(+), 1 deletion(-) > > > create mode 100644 src/splice-test.c > > > create mode 100755 tests/generic/720 > > > create mode 100644 tests/generic/720.out > > > > > > diff --git a/.gitignore b/.gitignore > > > index c8c815f9..26d4da11 100644 > > > --- a/.gitignore > > > +++ b/.gitignore > > > @@ -112,6 +112,7 @@ > > > /src/runas > > > /src/seek_copy_test > > > /src/seek_sanity_test > > > +/src/splice-test > > > /src/stale_handle > > > /src/stat_test > > > /src/swapon > > > diff --git a/src/Makefile b/src/Makefile > > > index c4fcf370..2920dfb1 100644 > > > --- a/src/Makefile > > > +++ b/src/Makefile > > > @@ -28,7 +28,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \ > > > attr-list-by-handle-cursor-test listxattr dio-interleaved t_dir_type \ > > > dio-invalidate-cache stat_test t_encrypted_d_revalidate \ > > > attr_replace_test swapon mkswap t_attr_corruption t_open_tmpfiles \ > > > - fscrypt-crypt-util bulkstat_null_ocount > > > + fscrypt-crypt-util bulkstat_null_ocount splice-test > > > > > > SUBDIRS = log-writes perf > > > > > > diff --git a/src/splice-test.c b/src/splice-test.c > > > new file mode 100644 > > > index 00000000..d3c12075 > > > --- /dev/null > > > +++ b/src/splice-test.c > > > @@ -0,0 +1,173 @@ > > > +// SPDX-License-Identifier: GPL-2.0-or-later > > > +/* > > > + * Copyright (C) 2019 ????????????????????????????? > > > + * Author: > > > + * > > > + * Make sure that reading and writing to a pipe via splice. > > > + */ > > > +#include <sys/types.h> > > > +#include <sys/stat.h> > > > +#include <sys/wait.h> > > > +#include <unistd.h> > > > +#include <fcntl.h> > > > +#include <err.h> > > > + > > > +#include <stdlib.h> > > > +#include <stdio.h> > > > +#include <stdbool.h> > > > +#include <string.h> > > > +#include <errno.h> > > > + > > > +#define SECTOR_SIZE 512 > > > +#define BUFFER_SIZE (150 * SECTOR_SIZE) > > > + > > > +void read_from_pipe(int fd, const char *filename, size_t size) > > > +{ > > > + char buffer[SECTOR_SIZE]; > > > + size_t sz; > > > + ssize_t ret; > > > + > > > + while (size) { > > > + sz = size; > > > + if (sz > sizeof buffer) > > > + sz = sizeof buffer; > > > + ret = read(fd, buffer, sz); > > > + if (ret < 0) > > > + err(1, "read: %s", filename); > > > + if (ret == 0) { > > > + fprintf(stderr, "read: %s: unexpected EOF\n", filename); > > > + exit(1); > > > + } > > > + size -= sz; > > > + } > > > +} > > > + > > > +void do_splice1(int fd, const char *filename, size_t size) > > > +{ > > > + bool retried = false; > > > + int pipefd[2]; > > > + > > > + if (pipe(pipefd) == -1) > > > + err(1, "pipe"); > > > + while (size) { > > > + ssize_t spliced; > > > + > > > + spliced = splice(fd, NULL, pipefd[1], NULL, size, SPLICE_F_MOVE); > > > + if (spliced == -1) { > > > + if (errno == EAGAIN && !retried) { > > > + retried = true; > > > + fprintf(stderr, "retrying splice\n"); > > > + sleep(1); > > > + continue; > > > + } > > > + err(1, "splice"); > > > + } > > > + read_from_pipe(pipefd[0], filename, spliced); > > > + size -= spliced; > > > + } > > > + close(pipefd[0]); > > > + close(pipefd[1]); > > > +} > > > + > > > +void do_splice2(int fd, const char *filename, size_t size) > > > +{ > > > + bool retried = false; > > > + int pipefd[2]; > > > + int pid; > > > + > > > + if (pipe(pipefd) == -1) > > > + err(1, "pipe"); > > > + > > > + pid = fork(); > > > + if (pid == 0) { > > > + close(pipefd[1]); > > > + read_from_pipe(pipefd[0], filename, size); > > > + exit(0); > > > + } else { > > > + close(pipefd[0]); > > > + while (size) { > > > + ssize_t spliced; > > > + > > > + spliced = splice(fd, NULL, pipefd[1], NULL, size, SPLICE_F_MOVE); > > > + if (spliced == -1) { > > > + if (errno == EAGAIN && !retried) { > > > + retried = true; > > > + fprintf(stderr, "retrying splice\n"); > > > + sleep(1); > > > + continue; > > > + } > > > + err(1, "splice"); > > > + } > > > + size -= spliced; > > > + } > > > + close(pipefd[1]); > > > + waitpid(pid, NULL, 0); > > > + } > > > +} > > > + > > > +void usage(const char *argv0) > > > +{ > > > + fprintf(stderr, "USAGE: %s [-rd] {filename}\n", basename(argv0)); > > > + exit(2); > > > +} > > > + > > > +int main(int argc, char *argv[]) > > > +{ > > > + void (*do_splice)(int fd, const char *filename, size_t size); > > > + const char *filename; > > > + char *buffer; > > > + int opt, open_flags, fd; > > > + ssize_t ret; > > > + > > > + do_splice = do_splice1; > > > + open_flags = O_CREAT | O_TRUNC | O_RDWR | O_DIRECT; > > > + > > > + while ((opt = getopt(argc, argv, "rd")) != -1) { > > > + switch(opt) { > > > + case 'r': > > > + do_splice = do_splice2; > > > + break; > > > + case 'd': > > > + open_flags &= ~O_DIRECT; > > > + break; > > > + default: /* '?' */ > > > + usage(argv[0]); > > > + } > > > + } > > > + > > > + if (optind >= argc) > > > + usage(argv[0]); > > > + filename = argv[optind]; > > > + > > > + printf("%s reader %s O_DIRECT\n", > > > + do_splice == do_splice1 ? "sequential" : "concurrent", > > > + (open_flags & O_DIRECT) ? "with" : "without"); > > > + > > > + buffer = aligned_alloc(SECTOR_SIZE, BUFFER_SIZE); > > > + if (buffer == NULL) > > > + err(1, "aligned_alloc"); > > > + > > > + fd = open(filename, open_flags, 0666); > > > + if (fd == -1) > > > + err(1, "open: %s", filename); > > > + > > > + memset(buffer, 'x', BUFFER_SIZE); > > > + ret = write(fd, buffer, BUFFER_SIZE); > > > + if (ret < 0) > > > + err(1, "write: %s", filename); > > > + if (ret != BUFFER_SIZE) { > > > + fprintf(stderr, "%s: short write\n", filename); > > > + exit(1); > > > + } > > > + > > > + ret = lseek(fd, 0, SEEK_SET); > > > + if (ret != 0) > > > + err(1, "lseek: %s", filename); > > > + > > > + do_splice(fd, filename, BUFFER_SIZE); > > > + > > > + if (unlink(filename) == -1) > > > + err(1, "unlink: %s", filename); > > > + > > > + return 0; > > > +} > > > diff --git a/tests/generic/720 b/tests/generic/720 > > > new file mode 100755 > > > index 00000000..b7f09c40 > > > --- /dev/null > > > +++ b/tests/generic/720 > > > @@ -0,0 +1,41 @@ > > > +#! /bin/bash > > > +# SPDX-License-Identifier: GPL-2.0-or-later > > > +# Copyright (c) 2019, Oracle and/or its affiliates. All Rights Reserved. > > > +# > > > +# FS QA Test No. 720 > > > +# > > > +# Test using splice() to read from pipes. > > > + > > > +seq=`basename $0` > > > +seqres=$RESULT_DIR/$seq > > > +echo "QA output created by $seq" > > > + > > > +here=`pwd` > > > +tmp=/tmp/$$ > > > +status=1 # failure is the default! > > > +trap "_cleanup; exit \$status" 0 1 2 3 15 > > > + > > > +_cleanup() > > > +{ > > > + cd / > > > + rm -f $TEST_DIR/a > > > +} > > > + > > > +# get standard environment, filters and checks > > > +. ./common/rc > > > + > > > +# real QA test starts here > > > +_supported_os Linux > > > +_supported_fs generic > > > +_require_test > > > + > > > +rm -f $seqres.full > > > + > > > +src/splice-test -r $TEST_DIR/a > > > +src/splice-test -rd $TEST_DIR/a > > > +src/splice-test $TEST_DIR/a > > > +src/splice-test -d $TEST_DIR/a > > > + > > > +# success, all done > > > +status=0 > > > +exit > > > diff --git a/tests/generic/720.out b/tests/generic/720.out > > > new file mode 100644 > > > index 00000000..b0fc9935 > > > --- /dev/null > > > +++ b/tests/generic/720.out > > > @@ -0,0 +1,7 @@ > > > +QA output created by 720 > > > +concurrent reader with O_DIRECT > > > +concurrent reader with O_DIRECT > > > +concurrent reader without O_DIRECT > > > +concurrent reader without O_DIRECT > > > +sequential reader with O_DIRECT > > > +sequential reader without O_DIRECT > > > diff --git a/tests/generic/group b/tests/generic/group > > > index cd418106..f75d4e60 100644 > > > --- a/tests/generic/group > > > +++ b/tests/generic/group > > > @@ -569,3 +569,4 @@ > > > 564 auto quick copy_range > > > 565 auto quick copy_range > > > 719 auto quick quota metadata > > > +720 auto quick rw pipe splice
