| Message ID | 1426530862-32276-1-git-send-email-milosz@adfin.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
> On Mar 16, 2015, at 12:34 PM, Milosz Tanski <milosz@adfin.com> wrote: > > preadv2 is a new syscall introduced that is like preadv2 but with flag Sorry, "preadv2 ... is like preadv2"? > argument. The first use case of this is to let us add a flag to perform a > non-blocking file using the page cache. This is also missing a Signed-off-by: line. Cheers, Andreas > --- > src/Makefile | 2 +- > src/preadv2-pwritev2.h | 52 +++++++++++++++++ > src/preadv2.c | 150 +++++++++++++++++++++++++++++++++++++++++++++++++ > tests/generic/067 | 85 ++++++++++++++++++++++++++++ > tests/generic/067.out | 9 +++ > tests/generic/group | 1 + > 6 files changed, 298 insertions(+), 1 deletion(-) > create mode 100644 src/preadv2-pwritev2.h > create mode 100644 src/preadv2.c > create mode 100755 tests/generic/067 > create mode 100644 tests/generic/067.out > > diff --git a/src/Makefile b/src/Makefile > index 4781736..f7d3681 100644 > --- a/src/Makefile > +++ b/src/Makefile > @@ -19,7 +19,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \ > bulkstat_unlink_test_modified t_dir_offset t_futimens t_immutable \ > stale_handle pwrite_mmap_blocked t_dir_offset2 seek_sanity_test \ > seek_copy_test t_readdir_1 t_readdir_2 fsync-tester nsexec cloner \ > - renameat2 t_getcwd e4compact > + renameat2 t_getcwd e4compact preadv2 > > SUBDIRS = > > diff --git a/src/preadv2-pwritev2.h b/src/preadv2-pwritev2.h > new file mode 100644 > index 0000000..786e524 > --- /dev/null > +++ b/src/preadv2-pwritev2.h > @@ -0,0 +1,52 @@ > +#ifndef PREADV2_PWRITEV2_H > +#define PREADV2_PWRITEV2_H > + > +#include "global.h" > + > +#ifndef HAVE_PREADV2 > +#include <sys/syscall.h> > + > +#if !defined(SYS_preadv2) && defined(__x86_64__) > +#define SYS_preadv2 323 > +#define SYS_pwritev2 324 > +#endif > + > +#if !defined (SYS_preadv2) && defined(__i386__) > +#define SYS_preadv2 359 > +#define SYS_pwritev2 360 > +#endif > + > +/* LO_HI_LONG taken from glibc */ > +#define LO_HI_LONG(val) \ > + (off_t) val, \ > + (off_t) ((((uint64_t) (val)) >> (sizeof (long) * 4)) >> (sizeof (long) * 4)) > + > +static inline ssize_t > +preadv2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags) > +{ > +#ifdef SYS_preadv2 > + return syscall(SYS_preadv2, fd, iov, iovcnt, LO_HI_LONG(offset), > + flags); > +#else > + errno = ENOSYS; > + return -1; > +#endif > +} > + > +static inline ssize_t > +pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags) > +{ > +#ifdef SYS_pwritev2 > + return syscall(SYS_pwritev2, fd, iov, iovcnt, LO_HI_LONG(offset), > + flags); > +#else > + errno = ENOSYS; > + return -1; > +#endif > +} > + > +#define RWF_NONBLOCK 0x00000001 > +#define RWF_DSYNC 0x00000002 > + > +#endif /* HAVE_PREADV2 */ > +#endif /* PREADV2_PWRITEV2_H */ > diff --git a/src/preadv2.c b/src/preadv2.c > new file mode 100644 > index 0000000..a4f89b5 > --- /dev/null > +++ b/src/preadv2.c > @@ -0,0 +1,150 @@ > +/* > + * Copyright 2014 Red Hat, Inc. All rights reserved. > + * Copyright 2015 Milosz Tanski > + * > + * License: GPLv2 > + * > + */ > +#include <stdio.h> > +#include <stdlib.h> > +#include <getopt.h> > +#include <string.h> > +#include <unistd.h> > +#include <errno.h> > +#include <linux/fs.h> /* for RWF_NONBLOCK */ > + > +/* > + * Once preadv2 is part of the upstream kernel and there is glibc support for > + * it. We'll add support for preadv2 to xfs_io and this will be unnecessary. > + */ > +#include "preadv2-pwritev2.h" > + > +/* > + * Test to see if the system call is implemented. If -EINVAL or -ENOSYS > + * are returned, consider the call unimplemented. All other errors are > + * considered success. > + * > + * Returns: 0 if the system call is implemented, 1 if the system call > + * is not implemented. > + */ > +int > +preadv2_check(int fd) > +{ > + int ret; > + struct iovec iov[] = {}; > + > + /* 0 length read; just check iof the syscall is there. > + * > + * - 0 length iovec > + * - Position is -1 (eg. use current position) > + */ > + ret = preadv2(fd, iov, 0, -1, 0); > + > + if (ret < 0) { > + if (errno == ENOSYS || errno == EINVAL) > + return 1; > + } > + > + return 0; > +} > + > +void > +usage(char *prog) > +{ > + fprintf(stderr, "Usage: %s [-v] [-ctdw] [-n] -p POS -l LEN <filename>\n\n", prog); > + fprintf(stderr, "General arguments:\n"); > + fprintf(stderr, " -v Verify that the syscall is supported and quit:\n"); > + fprintf(stderr, "\n"); > + fprintf(stderr, "Open arguments:\n"); > + fprintf(stderr, " -c Open file with O_CREAT flag\n"); > + fprintf(stderr, " -t Open file with O_TRUNC flag\n"); > + fprintf(stderr, " -d Open file with O_DIRECT flag\n"); > + fprintf(stderr, " -w Open file with O_RDWR flag vs O_RDONLY (default)\n"); > + fprintf(stderr, "\n"); > + fprintf(stderr, "preadv2 arguments:\n"); > + fprintf(stderr, " -n use RWF_NONBLOCK when performing read\n"); > + fprintf(stderr, " -p POS offset file to read at\n"); > + fprintf(stderr, " -l LEN length of file data to read\n"); > + fprintf(stderr, "\n"); > + fflush(stderr); > +} > + > +int > +main(int argc, char **argv) > +{ > + int fd; > + int ret; > + int opt; > + off_t pos = -1; > + struct iovec iov = { NULL, 0 }; > + int o_flags = 0; > + int r_flags = 0; > + char *filename; > + > + while ((opt = getopt(argc, argv, "vctdwnp:l:")) != -1) { > + switch (opt) { > + case 'v': > + /* > + * See if we were called to check for availability of > + * sys_preadv2. STDIN is okay, since we do a zero > + * length read (see man 2 read). > + */ > + ret = preadv2_check(STDIN_FILENO); > + exit(ret); > + case 'c': > + o_flags |= O_CREAT; > + break; > + case 't': > + o_flags |= O_TRUNC; > + break; > + case 'd': > + o_flags |= O_DIRECT; > + break; > + case 'w': > + o_flags |= O_RDWR; > + break; > + case 'n': > + r_flags |= RWF_NONBLOCK; > + break; > + case 'p': > + pos = atoll(optarg); > + break; > + case 'l': > + iov.iov_len = atoll(optarg); > + break; > + default: > + fprintf(stderr, "invalid option: %c\n", opt); > + usage(argv[0]); > + exit(1); > + } > + } > + > + if (optind >= argc) { > + usage(argv[0]); > + exit(1); > + } > + > + if ((o_flags & O_RDWR) != O_RDWR) > + o_flags |= O_RDONLY; > + > + if ((iov.iov_base = malloc(iov.iov_len)) == NULL) { > + perror("malloc"); > + exit(1); > + } > + > + filename = argv[optind]; > + fd = open(filename, o_flags); > + > + if (fd < 0) { > + perror("open"); > + exit(1); > + } > + > + if ((ret = preadv2(fd, &iov, 1, pos, r_flags)) == -1) { > + perror("preadv2"); > + exit(ret); > + } > + > + free(iov.iov_base); > + exit(0); > +} > diff --git a/tests/generic/067 b/tests/generic/067 > new file mode 100755 > index 0000000..4cc58f8 > --- /dev/null > +++ b/tests/generic/067 > @@ -0,0 +1,85 @@ > +#! /bin/bash > +# FS QA Test No. 067 > +# > +# Test for the preadv2 syscall > +# > +#----------------------------------------------------------------------- > +# Copyright (c) 2015 Milosz Tanski <mtanski@gmail.com>. All Rights Reserved. > +# > +# This program is free software; you can redistribute it and/or > +# modify it under the terms of the GNU General Public License as > +# published by the Free Software Foundation. > +# > +# This program is distributed in the hope that it would be useful, > +# but WITHOUT ANY WARRANTY; without even the implied warranty of > +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > +# GNU General Public License for more details. > +# > +# You should have received a copy of the GNU General Public License > +# along with this program; if not, write the Free Software Foundation, > +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA > +#----------------------------------------------------------------------- > +# > + > +seq=`basename $0` > +seqres=$RESULT_DIR/$seq > +echo "QA output created by $seq" > + > +here=`pwd` > +tmp=/tmp/$$ > +status=1 # failure is the default! > +trap "_cleanup; exit \$status" 0 1 2 3 15 > + > +_cleanup() > +{ > + cd / > + rm -f $tmp.* > +} > + > +# get standard environment, filters and checks > +. ./common/rc > +. ./common/filter > + > +# real QA test starts here > + > +# Modify as appropriate. > +_supported_fs generic > +_supported_os Linux > +_require_test > + > +# test file we'll be using > +file=$SCRATCH_MNT/067.preadv2.$$ > + > +# Create a file: > +# two regions of data and a hole in the middle > +# use O_DIRECT so it's not in the page cache > +echo "create file" > +$XFS_IO_PROG -t -f -d \ > + -c "pwrite 0 1024" \ > + -c "pwrite 2048 1024" \ > + $file > /dev/null > + > +# Make sure it returns EAGAIN on uncached data > +echo "uncached" > +$here/src/preadv2 -n -p 0 -l 1024 $file > + > +# Make sure we read in the whole file, after that RWF_NONBLOCK should return us all the data > +echo "cached" > +$XFS_IO_PROG -f $file -c "pread 0 4096" $file > /dev/null > +$here/src/preadv2 -n -p 0 -l 1024 $file > + > +# O_DIRECT and RWF_NONBLOCK should return EAGAIN always > +echo "O_DIRECT" > +$here/src/preadv2 -d -n -p 0 -l 1024 $file > + > +# Holes do not block > +echo "holes" > +$here/src/preadv2 -n -p 2048 -l 1024 $file > + > +# EOF behavior (no EAGAIN) > +echo "EOF" > +$here/src/preadv2 -n -p 3072 -l 1 $file > + > +# success, all done > +status=0 > +exit > diff --git a/tests/generic/067.out b/tests/generic/067.out > new file mode 100644 > index 0000000..6e3740f > --- /dev/null > +++ b/tests/generic/067.out > @@ -0,0 +1,9 @@ > +QA output created by 067 > +create file > +uncached > +preadv2: Resource temporarily unavailable > +cached > +O_DIRECT > +preadv2: Resource temporarily unavailable > +holes > +EOF > diff --git a/tests/generic/group b/tests/generic/group > index e5db772..91c5870 100644 > --- a/tests/generic/group > +++ b/tests/generic/group > @@ -69,6 +69,7 @@ > 064 auto quick prealloc > 065 metadata auto quick > 066 metadata auto quick > +067 auto quick rw > 068 other auto freeze dangerous stress > 069 rw udf auto quick > 070 attr udf auto quick stress > -- > 1.9.1 > > -- > To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html Cheers, Andreas -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On Mon, Mar 16, 2015 at 02:34:22PM -0400, Milosz Tanski wrote: > preadv2 is a new syscall introduced that is like preadv2 but with flag > argument. The first use case of this is to let us add a flag to perform a > non-blocking file using the page cache. > --- > src/Makefile | 2 +- > src/preadv2-pwritev2.h | 52 +++++++++++++++++ > src/preadv2.c | 150 +++++++++++++++++++++++++++++++++++++++++++++++++ You should add this syscall to support to xfs_io (in the xfsprogs package) rather than write a new helper for it. Mainly because: > +void > +usage(char *prog) > +{ > + fprintf(stderr, "Usage: %s [-v] [-ctdw] [-n] -p POS -l LEN <filename>\n\n", prog); > + fprintf(stderr, "General arguments:\n"); > + fprintf(stderr, " -v Verify that the syscall is supported and quit:\n"); > + fprintf(stderr, "\n"); > + fprintf(stderr, "Open arguments:\n"); > + fprintf(stderr, " -c Open file with O_CREAT flag\n"); > + fprintf(stderr, " -t Open file with O_TRUNC flag\n"); > + fprintf(stderr, " -d Open file with O_DIRECT flag\n"); > + fprintf(stderr, " -w Open file with O_RDWR flag vs O_RDONLY (default)\n"); > + fprintf(stderr, "\n"); > + fprintf(stderr, "preadv2 arguments:\n"); > + fprintf(stderr, " -n use RWF_NONBLOCK when performing read\n"); > + fprintf(stderr, " -p POS offset file to read at\n"); > + fprintf(stderr, " -l LEN length of file data to read\n"); The xfs_io pread command already supports all of these functions except for the RWF_NONBLOCK flag, and anyone testing bleeding edge functionality is also using a bleeding edge xfs_io binary. Then you test for whether the functionality is available via _require_xfs_io_command "preadv -n" ..... > +# test file we'll be using > +file=$SCRATCH_MNT/067.preadv2.$$ > + > +# Create a file: > +# two regions of data and a hole in the middle > +# use O_DIRECT so it's not in the page cache > +echo "create file" > +$XFS_IO_PROG -t -f -d \ > + -c "pwrite 0 1024" \ > + -c "pwrite 2048 1024" \ > + $file > /dev/null This does not create holes on most filesystems. You'll need to leave holes of up 64k so that 64k block size filesystem end up with single block holes in them. > +# Make sure it returns EAGAIN on uncached data > +echo "uncached" > +$here/src/preadv2 -n -p 0 -l 1024 $file $XFS_IO_PROG -c "pread -n 0 1024" $file | _filter_xfs_io > + > +# Make sure we read in the whole file, after that RWF_NONBLOCK should return us all the data > +echo "cached" > +$XFS_IO_PROG -f $file -c "pread 0 4096" $file > /dev/null > +$here/src/preadv2 -n -p 0 -l 1024 $file $XFS_IO_PROG -c "pread 0 4096" -c "pread -n 0 1024" $file | _filter_xfs_io > + > +# O_DIRECT and RWF_NONBLOCK should return EAGAIN always > +echo "O_DIRECT" > +$here/src/preadv2 -d -n -p 0 -l 1024 $file $XFS_IO_PROG -d -c "pread -n 0 1024" $file | _filter_xfs_io And so on.... Cheers, Dave.
On Mon, Mar 16, 2015 at 5:07 PM, Andreas Dilger <adilger@dilger.ca> wrote: > >> On Mar 16, 2015, at 12:34 PM, Milosz Tanski <milosz@adfin.com> wrote: >> >> preadv2 is a new syscall introduced that is like preadv2 but with flag > > Sorry, "preadv2 ... is like preadv2"? I already have a fix for in my branch. Robert Elliott was the first one to notice that (via private email). > >> argument. The first use case of this is to let us add a flag to perform a >> non-blocking file using the page cache. > > This is also missing a Signed-off-by: line. Good catch. I'm going to fix the above to issues, add a pre-test check for preadv2 (I just noticed it's missing) and I'm going to resend this patch. > > Cheers, Andreas >> --- >> src/Makefile | 2 +- >> src/preadv2-pwritev2.h | 52 +++++++++++++++++ >> src/preadv2.c | 150 +++++++++++++++++++++++++++++++++++++++++++++++++ >> tests/generic/067 | 85 ++++++++++++++++++++++++++++ >> tests/generic/067.out | 9 +++ >> tests/generic/group | 1 + >> 6 files changed, 298 insertions(+), 1 deletion(-) >> create mode 100644 src/preadv2-pwritev2.h >> create mode 100644 src/preadv2.c >> create mode 100755 tests/generic/067 >> create mode 100644 tests/generic/067.out >> >> diff --git a/src/Makefile b/src/Makefile >> index 4781736..f7d3681 100644 >> --- a/src/Makefile >> +++ b/src/Makefile >> @@ -19,7 +19,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \ >> bulkstat_unlink_test_modified t_dir_offset t_futimens t_immutable \ >> stale_handle pwrite_mmap_blocked t_dir_offset2 seek_sanity_test \ >> seek_copy_test t_readdir_1 t_readdir_2 fsync-tester nsexec cloner \ >> - renameat2 t_getcwd e4compact >> + renameat2 t_getcwd e4compact preadv2 >> >> SUBDIRS = >> >> diff --git a/src/preadv2-pwritev2.h b/src/preadv2-pwritev2.h >> new file mode 100644 >> index 0000000..786e524 >> --- /dev/null >> +++ b/src/preadv2-pwritev2.h >> @@ -0,0 +1,52 @@ >> +#ifndef PREADV2_PWRITEV2_H >> +#define PREADV2_PWRITEV2_H >> + >> +#include "global.h" >> + >> +#ifndef HAVE_PREADV2 >> +#include <sys/syscall.h> >> + >> +#if !defined(SYS_preadv2) && defined(__x86_64__) >> +#define SYS_preadv2 323 >> +#define SYS_pwritev2 324 >> +#endif >> + >> +#if !defined (SYS_preadv2) && defined(__i386__) >> +#define SYS_preadv2 359 >> +#define SYS_pwritev2 360 >> +#endif >> + >> +/* LO_HI_LONG taken from glibc */ >> +#define LO_HI_LONG(val) \ >> + (off_t) val, \ >> + (off_t) ((((uint64_t) (val)) >> (sizeof (long) * 4)) >> (sizeof (long) * 4)) >> + >> +static inline ssize_t >> +preadv2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags) >> +{ >> +#ifdef SYS_preadv2 >> + return syscall(SYS_preadv2, fd, iov, iovcnt, LO_HI_LONG(offset), >> + flags); >> +#else >> + errno = ENOSYS; >> + return -1; >> +#endif >> +} >> + >> +static inline ssize_t >> +pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags) >> +{ >> +#ifdef SYS_pwritev2 >> + return syscall(SYS_pwritev2, fd, iov, iovcnt, LO_HI_LONG(offset), >> + flags); >> +#else >> + errno = ENOSYS; >> + return -1; >> +#endif >> +} >> + >> +#define RWF_NONBLOCK 0x00000001 >> +#define RWF_DSYNC 0x00000002 >> + >> +#endif /* HAVE_PREADV2 */ >> +#endif /* PREADV2_PWRITEV2_H */ >> diff --git a/src/preadv2.c b/src/preadv2.c >> new file mode 100644 >> index 0000000..a4f89b5 >> --- /dev/null >> +++ b/src/preadv2.c >> @@ -0,0 +1,150 @@ >> +/* >> + * Copyright 2014 Red Hat, Inc. All rights reserved. >> + * Copyright 2015 Milosz Tanski >> + * >> + * License: GPLv2 >> + * >> + */ >> +#include <stdio.h> >> +#include <stdlib.h> >> +#include <getopt.h> >> +#include <string.h> >> +#include <unistd.h> >> +#include <errno.h> >> +#include <linux/fs.h> /* for RWF_NONBLOCK */ >> + >> +/* >> + * Once preadv2 is part of the upstream kernel and there is glibc support for >> + * it. We'll add support for preadv2 to xfs_io and this will be unnecessary. >> + */ >> +#include "preadv2-pwritev2.h" >> + >> +/* >> + * Test to see if the system call is implemented. If -EINVAL or -ENOSYS >> + * are returned, consider the call unimplemented. All other errors are >> + * considered success. >> + * >> + * Returns: 0 if the system call is implemented, 1 if the system call >> + * is not implemented. >> + */ >> +int >> +preadv2_check(int fd) >> +{ >> + int ret; >> + struct iovec iov[] = {}; >> + >> + /* 0 length read; just check iof the syscall is there. >> + * >> + * - 0 length iovec >> + * - Position is -1 (eg. use current position) >> + */ >> + ret = preadv2(fd, iov, 0, -1, 0); >> + >> + if (ret < 0) { >> + if (errno == ENOSYS || errno == EINVAL) >> + return 1; >> + } >> + >> + return 0; >> +} >> + >> +void >> +usage(char *prog) >> +{ >> + fprintf(stderr, "Usage: %s [-v] [-ctdw] [-n] -p POS -l LEN <filename>\n\n", prog); >> + fprintf(stderr, "General arguments:\n"); >> + fprintf(stderr, " -v Verify that the syscall is supported and quit:\n"); >> + fprintf(stderr, "\n"); >> + fprintf(stderr, "Open arguments:\n"); >> + fprintf(stderr, " -c Open file with O_CREAT flag\n"); >> + fprintf(stderr, " -t Open file with O_TRUNC flag\n"); >> + fprintf(stderr, " -d Open file with O_DIRECT flag\n"); >> + fprintf(stderr, " -w Open file with O_RDWR flag vs O_RDONLY (default)\n"); >> + fprintf(stderr, "\n"); >> + fprintf(stderr, "preadv2 arguments:\n"); >> + fprintf(stderr, " -n use RWF_NONBLOCK when performing read\n"); >> + fprintf(stderr, " -p POS offset file to read at\n"); >> + fprintf(stderr, " -l LEN length of file data to read\n"); >> + fprintf(stderr, "\n"); >> + fflush(stderr); >> +} >> + >> +int >> +main(int argc, char **argv) >> +{ >> + int fd; >> + int ret; >> + int opt; >> + off_t pos = -1; >> + struct iovec iov = { NULL, 0 }; >> + int o_flags = 0; >> + int r_flags = 0; >> + char *filename; >> + >> + while ((opt = getopt(argc, argv, "vctdwnp:l:")) != -1) { >> + switch (opt) { >> + case 'v': >> + /* >> + * See if we were called to check for availability of >> + * sys_preadv2. STDIN is okay, since we do a zero >> + * length read (see man 2 read). >> + */ >> + ret = preadv2_check(STDIN_FILENO); >> + exit(ret); >> + case 'c': >> + o_flags |= O_CREAT; >> + break; >> + case 't': >> + o_flags |= O_TRUNC; >> + break; >> + case 'd': >> + o_flags |= O_DIRECT; >> + break; >> + case 'w': >> + o_flags |= O_RDWR; >> + break; >> + case 'n': >> + r_flags |= RWF_NONBLOCK; >> + break; >> + case 'p': >> + pos = atoll(optarg); >> + break; >> + case 'l': >> + iov.iov_len = atoll(optarg); >> + break; >> + default: >> + fprintf(stderr, "invalid option: %c\n", opt); >> + usage(argv[0]); >> + exit(1); >> + } >> + } >> + >> + if (optind >= argc) { >> + usage(argv[0]); >> + exit(1); >> + } >> + >> + if ((o_flags & O_RDWR) != O_RDWR) >> + o_flags |= O_RDONLY; >> + >> + if ((iov.iov_base = malloc(iov.iov_len)) == NULL) { >> + perror("malloc"); >> + exit(1); >> + } >> + >> + filename = argv[optind]; >> + fd = open(filename, o_flags); >> + >> + if (fd < 0) { >> + perror("open"); >> + exit(1); >> + } >> + >> + if ((ret = preadv2(fd, &iov, 1, pos, r_flags)) == -1) { >> + perror("preadv2"); >> + exit(ret); >> + } >> + >> + free(iov.iov_base); >> + exit(0); >> +} >> diff --git a/tests/generic/067 b/tests/generic/067 >> new file mode 100755 >> index 0000000..4cc58f8 >> --- /dev/null >> +++ b/tests/generic/067 >> @@ -0,0 +1,85 @@ >> +#! /bin/bash >> +# FS QA Test No. 067 >> +# >> +# Test for the preadv2 syscall >> +# >> +#----------------------------------------------------------------------- >> +# Copyright (c) 2015 Milosz Tanski <mtanski@gmail.com>. All Rights Reserved. >> +# >> +# This program is free software; you can redistribute it and/or >> +# modify it under the terms of the GNU General Public License as >> +# published by the Free Software Foundation. >> +# >> +# This program is distributed in the hope that it would be useful, >> +# but WITHOUT ANY WARRANTY; without even the implied warranty of >> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the >> +# GNU General Public License for more details. >> +# >> +# You should have received a copy of the GNU General Public License >> +# along with this program; if not, write the Free Software Foundation, >> +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA >> +#----------------------------------------------------------------------- >> +# >> + >> +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 $tmp.* >> +} >> + >> +# get standard environment, filters and checks >> +. ./common/rc >> +. ./common/filter >> + >> +# real QA test starts here >> + >> +# Modify as appropriate. >> +_supported_fs generic >> +_supported_os Linux >> +_require_test >> + >> +# test file we'll be using >> +file=$SCRATCH_MNT/067.preadv2.$$ >> + >> +# Create a file: >> +# two regions of data and a hole in the middle >> +# use O_DIRECT so it's not in the page cache >> +echo "create file" >> +$XFS_IO_PROG -t -f -d \ >> + -c "pwrite 0 1024" \ >> + -c "pwrite 2048 1024" \ >> + $file > /dev/null >> + >> +# Make sure it returns EAGAIN on uncached data >> +echo "uncached" >> +$here/src/preadv2 -n -p 0 -l 1024 $file >> + >> +# Make sure we read in the whole file, after that RWF_NONBLOCK should return us all the data >> +echo "cached" >> +$XFS_IO_PROG -f $file -c "pread 0 4096" $file > /dev/null >> +$here/src/preadv2 -n -p 0 -l 1024 $file >> + >> +# O_DIRECT and RWF_NONBLOCK should return EAGAIN always >> +echo "O_DIRECT" >> +$here/src/preadv2 -d -n -p 0 -l 1024 $file >> + >> +# Holes do not block >> +echo "holes" >> +$here/src/preadv2 -n -p 2048 -l 1024 $file >> + >> +# EOF behavior (no EAGAIN) >> +echo "EOF" >> +$here/src/preadv2 -n -p 3072 -l 1 $file >> + >> +# success, all done >> +status=0 >> +exit >> diff --git a/tests/generic/067.out b/tests/generic/067.out >> new file mode 100644 >> index 0000000..6e3740f >> --- /dev/null >> +++ b/tests/generic/067.out >> @@ -0,0 +1,9 @@ >> +QA output created by 067 >> +create file >> +uncached >> +preadv2: Resource temporarily unavailable >> +cached >> +O_DIRECT >> +preadv2: Resource temporarily unavailable >> +holes >> +EOF >> diff --git a/tests/generic/group b/tests/generic/group >> index e5db772..91c5870 100644 >> --- a/tests/generic/group >> +++ b/tests/generic/group >> @@ -69,6 +69,7 @@ >> 064 auto quick prealloc >> 065 metadata auto quick >> 066 metadata auto quick >> +067 auto quick rw >> 068 other auto freeze dangerous stress >> 069 rw udf auto quick >> 070 attr udf auto quick stress >> -- >> 1.9.1 >> >> -- >> To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in >> the body of a message to majordomo@vger.kernel.org >> More majordomo info at http://vger.kernel.org/majordomo-info.html > > > Cheers, Andreas > > > > >
On Mon, Mar 16, 2015 at 6:02 PM, Dave Chinner <david@fromorbit.com> wrote: > On Mon, Mar 16, 2015 at 02:34:22PM -0400, Milosz Tanski wrote: >> preadv2 is a new syscall introduced that is like preadv2 but with flag >> argument. The first use case of this is to let us add a flag to perform a >> non-blocking file using the page cache. >> --- >> src/Makefile | 2 +- >> src/preadv2-pwritev2.h | 52 +++++++++++++++++ >> src/preadv2.c | 150 +++++++++++++++++++++++++++++++++++++++++++++++++ > > You should add this syscall to support to xfs_io (in the xfsprogs > package) rather than write a new helper for it. Mainly because: > >> +void >> +usage(char *prog) >> +{ >> + fprintf(stderr, "Usage: %s [-v] [-ctdw] [-n] -p POS -l LEN <filename>\n\n", prog); >> + fprintf(stderr, "General arguments:\n"); >> + fprintf(stderr, " -v Verify that the syscall is supported and quit:\n"); >> + fprintf(stderr, "\n"); >> + fprintf(stderr, "Open arguments:\n"); >> + fprintf(stderr, " -c Open file with O_CREAT flag\n"); >> + fprintf(stderr, " -t Open file with O_TRUNC flag\n"); >> + fprintf(stderr, " -d Open file with O_DIRECT flag\n"); >> + fprintf(stderr, " -w Open file with O_RDWR flag vs O_RDONLY (default)\n"); >> + fprintf(stderr, "\n"); >> + fprintf(stderr, "preadv2 arguments:\n"); >> + fprintf(stderr, " -n use RWF_NONBLOCK when performing read\n"); >> + fprintf(stderr, " -p POS offset file to read at\n"); >> + fprintf(stderr, " -l LEN length of file data to read\n"); > > The xfs_io pread command already supports all of these functions > except for the RWF_NONBLOCK flag, and anyone testing bleeding edge > functionality is also using a bleeding edge xfs_io binary. > > Then you test for whether the functionality is available via > _require_xfs_io_command "preadv -n" > > ..... >> +# test file we'll be using >> +file=$SCRATCH_MNT/067.preadv2.$$ >> + >> +# Create a file: >> +# two regions of data and a hole in the middle >> +# use O_DIRECT so it's not in the page cache >> +echo "create file" >> +$XFS_IO_PROG -t -f -d \ >> + -c "pwrite 0 1024" \ >> + -c "pwrite 2048 1024" \ >> + $file > /dev/null > > This does not create holes on most filesystems. You'll need to leave > holes of up 64k so that 64k block size filesystem end up with single > block holes in them. Noted and I shall fix this in the next round. > >> +# Make sure it returns EAGAIN on uncached data >> +echo "uncached" >> +$here/src/preadv2 -n -p 0 -l 1024 $file > > $XFS_IO_PROG -c "pread -n 0 1024" $file | _filter_xfs_io > >> + >> +# Make sure we read in the whole file, after that RWF_NONBLOCK should return us all the data >> +echo "cached" >> +$XFS_IO_PROG -f $file -c "pread 0 4096" $file > /dev/null >> +$here/src/preadv2 -n -p 0 -l 1024 $file > > $XFS_IO_PROG -c "pread 0 4096" -c "pread -n 0 1024" $file | _filter_xfs_io > >> + >> +# O_DIRECT and RWF_NONBLOCK should return EAGAIN always >> +echo "O_DIRECT" >> +$here/src/preadv2 -d -n -p 0 -l 1024 $file > > $XFS_IO_PROG -d -c "pread -n 0 1024" $file | _filter_xfs_io > > And so on.... > > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com Dave, My plan is/was to wait till the main patch makes it into the upstream linux kernel with the syscall numbers are set in stone. Possibly after till glibc adds support for them. After that I was going remove my preadv2 application from xfs_tests and add that functionality to xfs_io. With xfs_io living in separate repository I wanted to the case when/if syscall numbers change (there's a bunch of new syscalls queued around epoll) of having somebody test against xfs_io that has preadv2 but bad ids. As a side note, I did add mlock / munlock support to xfs_io that I'll send in another patch.
On Mon, Mar 16, 2015 at 06:11:19PM -0400, Milosz Tanski wrote: > On Mon, Mar 16, 2015 at 6:02 PM, Dave Chinner <david@fromorbit.com> wrote: > > On Mon, Mar 16, 2015 at 02:34:22PM -0400, Milosz Tanski wrote: > >> preadv2 is a new syscall introduced that is like preadv2 but with flag > >> argument. The first use case of this is to let us add a flag to perform a > >> non-blocking file using the page cache. > >> --- > >> src/Makefile | 2 +- > >> src/preadv2-pwritev2.h | 52 +++++++++++++++++ > >> src/preadv2.c | 150 +++++++++++++++++++++++++++++++++++++++++++++++++ > > > > You should add this syscall to support to xfs_io (in the xfsprogs > > package) rather than write a new helper for it. Mainly because: > > > >> +void > >> +usage(char *prog) > >> +{ > >> + fprintf(stderr, "Usage: %s [-v] [-ctdw] [-n] -p POS -l LEN <filename>\n\n", prog); > >> + fprintf(stderr, "General arguments:\n"); > >> + fprintf(stderr, " -v Verify that the syscall is supported and quit:\n"); > >> + fprintf(stderr, "\n"); > >> + fprintf(stderr, "Open arguments:\n"); > >> + fprintf(stderr, " -c Open file with O_CREAT flag\n"); > >> + fprintf(stderr, " -t Open file with O_TRUNC flag\n"); > >> + fprintf(stderr, " -d Open file with O_DIRECT flag\n"); > >> + fprintf(stderr, " -w Open file with O_RDWR flag vs O_RDONLY (default)\n"); > >> + fprintf(stderr, "\n"); > >> + fprintf(stderr, "preadv2 arguments:\n"); > >> + fprintf(stderr, " -n use RWF_NONBLOCK when performing read\n"); > >> + fprintf(stderr, " -p POS offset file to read at\n"); > >> + fprintf(stderr, " -l LEN length of file data to read\n"); > > > > The xfs_io pread command already supports all of these functions > > except for the RWF_NONBLOCK flag, and anyone testing bleeding edge > > functionality is also using a bleeding edge xfs_io binary. > > > > Then you test for whether the functionality is available via > > _require_xfs_io_command "preadv -n" > > > > ..... > >> +# test file we'll be using > >> +file=$SCRATCH_MNT/067.preadv2.$$ > >> + > >> +# Create a file: > >> +# two regions of data and a hole in the middle > >> +# use O_DIRECT so it's not in the page cache > >> +echo "create file" > >> +$XFS_IO_PROG -t -f -d \ > >> + -c "pwrite 0 1024" \ > >> + -c "pwrite 2048 1024" \ > >> + $file > /dev/null > > > > This does not create holes on most filesystems. You'll need to leave > > holes of up 64k so that 64k block size filesystem end up with single > > block holes in them. > > Noted and I shall fix this in the next round. > > > > >> +# Make sure it returns EAGAIN on uncached data > >> +echo "uncached" > >> +$here/src/preadv2 -n -p 0 -l 1024 $file > > > > $XFS_IO_PROG -c "pread -n 0 1024" $file | _filter_xfs_io > > > >> + > >> +# Make sure we read in the whole file, after that RWF_NONBLOCK should return us all the data > >> +echo "cached" > >> +$XFS_IO_PROG -f $file -c "pread 0 4096" $file > /dev/null > >> +$here/src/preadv2 -n -p 0 -l 1024 $file > > > > $XFS_IO_PROG -c "pread 0 4096" -c "pread -n 0 1024" $file | _filter_xfs_io > > > >> + > >> +# O_DIRECT and RWF_NONBLOCK should return EAGAIN always > >> +echo "O_DIRECT" > >> +$here/src/preadv2 -d -n -p 0 -l 1024 $file > > > > $XFS_IO_PROG -d -c "pread -n 0 1024" $file | _filter_xfs_io > > > > And so on.... > > > > Cheers, > > > > Dave. > > -- > > Dave Chinner > > david@fromorbit.com > > Dave, > > My plan is/was to wait till the main patch makes it into the upstream > linux kernel with the syscall numbers are set in stone. Possibly after > till glibc adds support for them. After that I was going remove my > preadv2 application from xfs_tests and add that functionality to > xfs_io. I wouldn't worry too much about glibc - once the syscall numbers are defined we can test for them directly, I think, like we do for supporting various ioctls. > With xfs_io living in separate repository I wanted to the case when/if > syscall numbers change (there's a bunch of new syscalls queued around > epoll) of having somebody test against xfs_io that has preadv2 but bad > ids. If the syscall numbers change, it's simple to patch, and as long as we have set the syscall numbers in stone before a xfsprogs release is done then there won't be any problems... Cheers, Dave.
diff --git a/src/Makefile b/src/Makefile index 4781736..f7d3681 100644 --- a/src/Makefile +++ b/src/Makefile @@ -19,7 +19,7 @@ LINUX_TARGETS = xfsctl bstat t_mtab getdevicesize preallo_rw_pattern_reader \ bulkstat_unlink_test_modified t_dir_offset t_futimens t_immutable \ stale_handle pwrite_mmap_blocked t_dir_offset2 seek_sanity_test \ seek_copy_test t_readdir_1 t_readdir_2 fsync-tester nsexec cloner \ - renameat2 t_getcwd e4compact + renameat2 t_getcwd e4compact preadv2 SUBDIRS = diff --git a/src/preadv2-pwritev2.h b/src/preadv2-pwritev2.h new file mode 100644 index 0000000..786e524 --- /dev/null +++ b/src/preadv2-pwritev2.h @@ -0,0 +1,52 @@ +#ifndef PREADV2_PWRITEV2_H +#define PREADV2_PWRITEV2_H + +#include "global.h" + +#ifndef HAVE_PREADV2 +#include <sys/syscall.h> + +#if !defined(SYS_preadv2) && defined(__x86_64__) +#define SYS_preadv2 323 +#define SYS_pwritev2 324 +#endif + +#if !defined (SYS_preadv2) && defined(__i386__) +#define SYS_preadv2 359 +#define SYS_pwritev2 360 +#endif + +/* LO_HI_LONG taken from glibc */ +#define LO_HI_LONG(val) \ + (off_t) val, \ + (off_t) ((((uint64_t) (val)) >> (sizeof (long) * 4)) >> (sizeof (long) * 4)) + +static inline ssize_t +preadv2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags) +{ +#ifdef SYS_preadv2 + return syscall(SYS_preadv2, fd, iov, iovcnt, LO_HI_LONG(offset), + flags); +#else + errno = ENOSYS; + return -1; +#endif +} + +static inline ssize_t +pwritev2(int fd, const struct iovec *iov, int iovcnt, off_t offset, int flags) +{ +#ifdef SYS_pwritev2 + return syscall(SYS_pwritev2, fd, iov, iovcnt, LO_HI_LONG(offset), + flags); +#else + errno = ENOSYS; + return -1; +#endif +} + +#define RWF_NONBLOCK 0x00000001 +#define RWF_DSYNC 0x00000002 + +#endif /* HAVE_PREADV2 */ +#endif /* PREADV2_PWRITEV2_H */ diff --git a/src/preadv2.c b/src/preadv2.c new file mode 100644 index 0000000..a4f89b5 --- /dev/null +++ b/src/preadv2.c @@ -0,0 +1,150 @@ +/* + * Copyright 2014 Red Hat, Inc. All rights reserved. + * Copyright 2015 Milosz Tanski + * + * License: GPLv2 + * + */ +#include <stdio.h> +#include <stdlib.h> +#include <getopt.h> +#include <string.h> +#include <unistd.h> +#include <errno.h> +#include <linux/fs.h> /* for RWF_NONBLOCK */ + +/* + * Once preadv2 is part of the upstream kernel and there is glibc support for + * it. We'll add support for preadv2 to xfs_io and this will be unnecessary. + */ +#include "preadv2-pwritev2.h" + +/* + * Test to see if the system call is implemented. If -EINVAL or -ENOSYS + * are returned, consider the call unimplemented. All other errors are + * considered success. + * + * Returns: 0 if the system call is implemented, 1 if the system call + * is not implemented. + */ +int +preadv2_check(int fd) +{ + int ret; + struct iovec iov[] = {}; + + /* 0 length read; just check iof the syscall is there. + * + * - 0 length iovec + * - Position is -1 (eg. use current position) + */ + ret = preadv2(fd, iov, 0, -1, 0); + + if (ret < 0) { + if (errno == ENOSYS || errno == EINVAL) + return 1; + } + + return 0; +} + +void +usage(char *prog) +{ + fprintf(stderr, "Usage: %s [-v] [-ctdw] [-n] -p POS -l LEN <filename>\n\n", prog); + fprintf(stderr, "General arguments:\n"); + fprintf(stderr, " -v Verify that the syscall is supported and quit:\n"); + fprintf(stderr, "\n"); + fprintf(stderr, "Open arguments:\n"); + fprintf(stderr, " -c Open file with O_CREAT flag\n"); + fprintf(stderr, " -t Open file with O_TRUNC flag\n"); + fprintf(stderr, " -d Open file with O_DIRECT flag\n"); + fprintf(stderr, " -w Open file with O_RDWR flag vs O_RDONLY (default)\n"); + fprintf(stderr, "\n"); + fprintf(stderr, "preadv2 arguments:\n"); + fprintf(stderr, " -n use RWF_NONBLOCK when performing read\n"); + fprintf(stderr, " -p POS offset file to read at\n"); + fprintf(stderr, " -l LEN length of file data to read\n"); + fprintf(stderr, "\n"); + fflush(stderr); +} + +int +main(int argc, char **argv) +{ + int fd; + int ret; + int opt; + off_t pos = -1; + struct iovec iov = { NULL, 0 }; + int o_flags = 0; + int r_flags = 0; + char *filename; + + while ((opt = getopt(argc, argv, "vctdwnp:l:")) != -1) { + switch (opt) { + case 'v': + /* + * See if we were called to check for availability of + * sys_preadv2. STDIN is okay, since we do a zero + * length read (see man 2 read). + */ + ret = preadv2_check(STDIN_FILENO); + exit(ret); + case 'c': + o_flags |= O_CREAT; + break; + case 't': + o_flags |= O_TRUNC; + break; + case 'd': + o_flags |= O_DIRECT; + break; + case 'w': + o_flags |= O_RDWR; + break; + case 'n': + r_flags |= RWF_NONBLOCK; + break; + case 'p': + pos = atoll(optarg); + break; + case 'l': + iov.iov_len = atoll(optarg); + break; + default: + fprintf(stderr, "invalid option: %c\n", opt); + usage(argv[0]); + exit(1); + } + } + + if (optind >= argc) { + usage(argv[0]); + exit(1); + } + + if ((o_flags & O_RDWR) != O_RDWR) + o_flags |= O_RDONLY; + + if ((iov.iov_base = malloc(iov.iov_len)) == NULL) { + perror("malloc"); + exit(1); + } + + filename = argv[optind]; + fd = open(filename, o_flags); + + if (fd < 0) { + perror("open"); + exit(1); + } + + if ((ret = preadv2(fd, &iov, 1, pos, r_flags)) == -1) { + perror("preadv2"); + exit(ret); + } + + free(iov.iov_base); + exit(0); +} diff --git a/tests/generic/067 b/tests/generic/067 new file mode 100755 index 0000000..4cc58f8 --- /dev/null +++ b/tests/generic/067 @@ -0,0 +1,85 @@ +#! /bin/bash +# FS QA Test No. 067 +# +# Test for the preadv2 syscall +# +#----------------------------------------------------------------------- +# Copyright (c) 2015 Milosz Tanski <mtanski@gmail.com>. All Rights Reserved. +# +# This program is free software; you can redistribute it and/or +# modify it under the terms of the GNU General Public License as +# published by the Free Software Foundation. +# +# This program is distributed in the hope that it would be useful, +# but WITHOUT ANY WARRANTY; without even the implied warranty of +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +# GNU General Public License for more details. +# +# You should have received a copy of the GNU General Public License +# along with this program; if not, write the Free Software Foundation, +# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA +#----------------------------------------------------------------------- +# + +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 $tmp.* +} + +# get standard environment, filters and checks +. ./common/rc +. ./common/filter + +# real QA test starts here + +# Modify as appropriate. +_supported_fs generic +_supported_os Linux +_require_test + +# test file we'll be using +file=$SCRATCH_MNT/067.preadv2.$$ + +# Create a file: +# two regions of data and a hole in the middle +# use O_DIRECT so it's not in the page cache +echo "create file" +$XFS_IO_PROG -t -f -d \ + -c "pwrite 0 1024" \ + -c "pwrite 2048 1024" \ + $file > /dev/null + +# Make sure it returns EAGAIN on uncached data +echo "uncached" +$here/src/preadv2 -n -p 0 -l 1024 $file + +# Make sure we read in the whole file, after that RWF_NONBLOCK should return us all the data +echo "cached" +$XFS_IO_PROG -f $file -c "pread 0 4096" $file > /dev/null +$here/src/preadv2 -n -p 0 -l 1024 $file + +# O_DIRECT and RWF_NONBLOCK should return EAGAIN always +echo "O_DIRECT" +$here/src/preadv2 -d -n -p 0 -l 1024 $file + +# Holes do not block +echo "holes" +$here/src/preadv2 -n -p 2048 -l 1024 $file + +# EOF behavior (no EAGAIN) +echo "EOF" +$here/src/preadv2 -n -p 3072 -l 1 $file + +# success, all done +status=0 +exit diff --git a/tests/generic/067.out b/tests/generic/067.out new file mode 100644 index 0000000..6e3740f --- /dev/null +++ b/tests/generic/067.out @@ -0,0 +1,9 @@ +QA output created by 067 +create file +uncached +preadv2: Resource temporarily unavailable +cached +O_DIRECT +preadv2: Resource temporarily unavailable +holes +EOF diff --git a/tests/generic/group b/tests/generic/group index e5db772..91c5870 100644 --- a/tests/generic/group +++ b/tests/generic/group @@ -69,6 +69,7 @@ 064 auto quick prealloc 065 metadata auto quick 066 metadata auto quick +067 auto quick rw 068 other auto freeze dangerous stress 069 rw udf auto quick 070 attr udf auto quick stress