diff options
| -rw-r--r-- | NEWS | 3 | ||||
| -rw-r--r-- | doc/coreutils.texi | 4 | ||||
| -rw-r--r-- | src/dd.c | 10 | ||||
| -rw-r--r-- | tests/Makefile.am | 1 | ||||
| -rwxr-xr-x | tests/dd/direct | 40 |
5 files changed, 57 insertions, 1 deletions
@@ -4,6 +4,9 @@ GNU coreutils NEWS -*- outline -*- ** Bug fixes + dd's oflag=direct option now works even when the size of the input + is not a multiple of e.g., 512 bytes. + install runs faster again with SELinux enabled [introduced in coreutils-7.0] diff --git a/doc/coreutils.texi b/doc/coreutils.texi index acec76e4c..90a54b268 100644 --- a/doc/coreutils.texi +++ b/doc/coreutils.texi @@ -7861,6 +7861,10 @@ same time. @opindex direct @cindex direct I/O Use direct I/O for data, avoiding the buffer cache. +Note that the kernel may impose restrictions on read or write buffer sizes. +For example, with an ext4 destination file system and a linux-based kernel, +using @samp{oflag=direct} will cause writes to fail with @code{EINVAL} if the +output buffer size is not a multiple of 512. @item directory @opindex directory @@ -837,6 +837,14 @@ iwrite (int fd, char const *buf, size_t size) { size_t total_written = 0; + if ((output_flags & O_DIRECT) && size < output_blocksize) + { + int old_flags = fcntl (STDOUT_FILENO, F_GETFL); + if (fcntl (STDOUT_FILENO, F_SETFL, old_flags & ~O_DIRECT) != 0) + error (0, errno, _("failed to turn off O_DIRECT: %s"), + quote (output_file)); + } + while (total_written < size) { ssize_t nwritten; @@ -1897,7 +1905,7 @@ main (int argc, char **argv) || S_ISDIR (stdout_stat.st_mode) || S_TYPEISSHM (&stdout_stat)) error (EXIT_FAILURE, ftruncate_errno, - _("truncating at %"PRIuMAX" bytes in output file %s"), + _("failed to truncate to %"PRIuMAX" bytes in output file %s"), size, quote (output_file)); } } diff --git a/tests/Makefile.am b/tests/Makefile.am index ad19d0264..6ad61331c 100644 --- a/tests/Makefile.am +++ b/tests/Makefile.am @@ -298,6 +298,7 @@ TESTS = \ cp/src-base-dot \ cp/symlink-slash \ cp/thru-dangling \ + dd/direct \ dd/misc \ dd/not-rewound \ dd/reblock \ diff --git a/tests/dd/direct b/tests/dd/direct new file mode 100755 index 000000000..7e80bee15 --- /dev/null +++ b/tests/dd/direct @@ -0,0 +1,40 @@ +#!/bin/sh +# ensure that dd's oflag=direct works + +# Copyright (C) 2009 Free Software Foundation, Inc. + +# 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, either version 3 of the License, or +# (at your option) any later version. + +# This program is distributed in the hope that it will 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, see <http://www.gnu.org/licenses/>. + +if test "$VERBOSE" = yes; then + set -x + dd --version +fi + +. $srcdir/test-lib.sh + +truncate -s 8192 in || framework_failure +dd if=in oflag=direct of=out 2> /dev/null \ + || skip_test_ 'this file system lacks support for O_DIRECT' + +truncate -s 511 short || framework_failure +truncate -s 8191 m1 || framework_failure +truncate -s 8193 p1 || framework_failure + +fail=0 +for i in short m1 p1; do + rm -f out + dd if=$i oflag=direct of=out || fail=1 +done + +Exit $fail |