[PATCH 1/5] src/copy_file_range: Add a program for testing vfs_copy_file_range()

Anna Schumaker
2016-05-13T20:50:57Z

This will be used by the various copy tests to call the Linux
copy_file_range() system call. I used src/cloner.c as a reference while
writing this tool.

Signed-off-by: Anna Schumaker <Anna.Schumaker@Netapp.com>
---
.gitignore | 1 +
common/rc | 7 ++
src/Makefile | 3 +-
src/copy_file_range.c | 189 ++++++++++++++++++++++++++++++++++++++++++++++++++
4 files changed, 199 insertions(+), 1 deletion(-)
create mode 100644 src/copy_file_range.c

diff --git a/.gitignore b/.gitignore
index f9ea1fa..07cb94b 100644
--- a/.gitignore
+++ b/.gitignore
@@ -38,6 +38,7 @@
/src/bstat
/src/bulkstat_unlink_test
/src/bulkstat_unlink_test_modified
+/src/copy_file_range
/src/dbtest
/src/devzero
/src/dirperf
diff --git a/common/rc b/common/rc
index 8bec836..735ff7a 100644
--- a/common/rc
+++ b/common/rc
@@ -2909,6 +2909,13 @@ _require_cloner()
_notrun "cloner binary not present at $CLONER_PROG"
}

+_require_copy_file_range()
+{
+ COPY_FILE_RANGE_PROG=$here/src/copy_file_range
+ [ -x $COPY_FILE_RANGE_PROG ] || \
+ _notrun "copy file range binary not present at $COPY_FILE_RANGE_PROG"
+}
+
_require_atime()
{
if [ "$FSTYP" == "nfs" ]; then
diff --git a/src/Makefile b/src/Makefile
index 1bf318b..b1b5766 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -20,7 +20,8 @@ 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 test-nextquota punch-alternating
+ renameat2 t_getcwd e4compact test-nextquota punch-alternating \
+ copy_file_range

SUBDIRS =

diff --git a/src/copy_file_range.c b/src/copy_file_range.c
new file mode 100644
index 0000000..067de26
--- /dev/null
+++ b/src/copy_file_range.c
@@ -0,0 +1,189 @@
+/*
+ * Tiny program to perform file range copies using the Linux system call.
+ *
+ * Copyright (c) 2016 Netapp, Inc. 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; either version 2 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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+#include <errno.h>
+#include <fcntl.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/syscall.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+static void
+usage(char *name, const char *msg)
+{
+ printf("Fatal: %s\n"
+ "Usage:\n"
+ "%s [options] <src_file> <dest_file>\n"
+ "\tA full file copy is performed by default, "
+ "unless any of the following are specified:\n"
+ "\t-s <offset>: source file offset (default = 0)\n"
+ "\t-d <offset>: destination file offset (default = 0)\n"
+ "\t-l <length>: length of copy (default = 0)\n",
+ msg, name);
+ _exit(1);
+}
+
+static loff_t
+copy_file_range(int src_fd, loff_t *src_pos, int dst_fd, loff_t *dst_pos,
+ size_t len, unsigned int flags)
+{
+ loff_t ret;
+
+ do {
+ ret = syscall(__NR_copy_file_range, src_fd, src_pos,
+ dst_fd, dst_pos,
+ len, flags);
+ if (ret == -1)
+ return errno;
+ len -= ret;
+ } while (len > 0);
+
+ return 0;
+}
+
+static loff_t
+copy_file(int src_fd, int dst_fd, unsigned int flags)
+{
+ struct stat stat;
+ loff_t src_pos = 0;
+ loff_t dst_pos = 0;
+ size_t len;
+ loff_t ret;
+
+ ret = fstat(src_fd, &stat);
+ if (ret == -1) {
+ ret = errno;
+ printf("stat failed: %s\n", strerror(ret));
+ return ret;
+ }
+
+ len = stat.st_size;
+ ret = ftruncate(dst_fd, 0);
+ if (ret == -1) {
+ ret = errno;
+ printf("truncate failed: %s\n", strerror(ret));
+ return ret;
+ }
+
+ return copy_file_range(src_fd, &src_pos, dst_fd, &dst_pos, len, flags);
+}
+
+
+int
+main(int argc, char **argv)
+{
+ char *src_file, *dst_file;
+ bool full_file = true;
+ loff_t src_off = 0;
+ loff_t dst_off = 0;
+ int src_fd, dst_fd;
+ size_t len = 0;
+ int opt, ret;
+
+ while ((opt = getopt(argc, argv, "s:d:l:")) != -1) {
+ char *sval_end;
+ switch (opt) {
+ case 's':
+ errno = 0;
+ src_off = strtoull(optarg, &sval_end, 10);
+ if ((errno) || (*sval_end != '\0'))
+ usage(argv[0], "invalid source offset");
+ full_file = false;
+ break;
+ case 'd':
+ errno = 0;
+ dst_off = strtoull(optarg, &sval_end, 10);
+ if ((errno) || (*sval_end != '\0'))
+ usage(argv[0], "invalid destination offset");
+ full_file = false;
+ break;
+ case 'l':
+ errno = 0;
+ len = strtoul(optarg, &sval_end, 10);
+ if ((errno) || (*sval_end != '\0'))
+ usage(argv[0], "invalid length");
+ full_file = false;
+ break;
+ default:
+ usage(argv[0], "invalid argument");
+ }
+ }
+
+ /* should be exactly two args left */
+ if (optind != argc - 2)
+ usage(argv[0], "src_file and dst_file arguments are mandatory");
+
+ src_file = (char *)strdup(argv[optind++]);
+ if (src_file == NULL) {
+ ret = ENOMEM;
+ printf("no memory\n");
+ goto err_out;
+ }
+ dst_file = (char *)strdup(argv[optind++]);
+ if (dst_file == NULL) {
+ ret = ENOMEM;
+ printf("no memory\n");
+ goto err_src_free;
+ }
+
+ src_fd = open(src_file, O_RDONLY);
+ if (src_fd == -1) {
+ ret = errno;
+ printf("failed to open %s: %s\n", src_file, strerror(errno));
+ goto err_dst_free;
+ }
+ dst_fd = open(dst_file, O_CREAT | O_WRONLY, 0644);
+ if (dst_fd == -1) {
+ ret = errno;
+ printf("failed to open %s: %s\n", dst_file, strerror(errno));
+ goto err_src_close;
+ }
+
+ if (full_file) {
+ ret = copy_file(src_fd, dst_fd, 0);
+ } else {
+ ret = copy_file_range(src_fd, &src_off, dst_fd, &dst_off, len, 0);
+ }
+ if (ret != 0) {
+ printf("copy failed: %s\n", strerror(ret));
+ goto err_dst_close;
+ }
+
+ ret = 0;
+err_dst_close:
+ if (close(dst_fd)) {
+ ret |= errno;
+ printf("failed to close dst file: %s\n", strerror(errno));
+ }
+err_src_close:
+ if (close(src_fd)) {
+ ret |= errno;
+ printf("failed to close src file: %s\n", strerror(errno));
+ }
+err_dst_free:
+ free(dst_file);
+err_src_free:
+ free(src_file);
+err_out:
+ return ret;
+}
--
2.8.2