io/sync_file_range.c - preadv2 - githubmirror/xfsprogs

io/sync_file_range.c
107 строк3 KB
Dave Chinner
xfs_io: add sync_file_range support
25 сен 2012, 01:38
25 сен 2012, 01:38a278c38
/*
 * Copyright (c) 2012 Red Hat, 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.
 *
 * 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
 */

#include <xfs/xfs.h>
#include <xfs/command.h>
#include <xfs/input.h>
#include "init.h"
#include "io.h"

static cmdinfo_t sync_range_cmd;

static void
sync_range_help(void)
{
	printf(_(
"\n"
" Trigger specific writeback commands on a range of the current file\n"
"\n"
" With no options, the SYNC_FILE_RANGE_WRITE is implied.\n"
" -a -- wait for IO to finish after writing (SYNC_FILE_RANGE_WAIT_AFTER).\n"
" -b -- wait for IO to finish before writing (SYNC_FILE_RANGE_WAIT_BEFORE).\n"
" -w -- write dirty data in range (SYNC_FILE_RANGE_WRITE).\n"
"\n"));
}

static int
sync_range_f(
	int		argc,
	char		**argv)
{
	off64_t		offset = 0, length = 0;
	int		c, sync_mode = 0;
	size_t		blocksize, sectsize;

	while ((c = getopt(argc, argv, "abw")) != EOF) {
		switch (c) {
		case 'a':
			sync_mode = SYNC_FILE_RANGE_WAIT_AFTER;
			break;
		case 'b':
			sync_mode = SYNC_FILE_RANGE_WAIT_BEFORE;
			break;
		case 'w':
			sync_mode = SYNC_FILE_RANGE_WRITE;
			break;
		default:
			return command_usage(&sync_range_cmd);
		}
	}

	/* default to just starting writeback on the range */
	if (!sync_mode)
		sync_mode = SYNC_FILE_RANGE_WRITE;

	if (optind != argc - 2)
		return command_usage(&sync_range_cmd);
	init_cvtnum(&blocksize, &sectsize);
	offset = cvtnum(blocksize, sectsize, argv[optind]);
	if (offset < 0) {
		printf(_("non-numeric offset argument -- %s\n"),
			argv[optind]);
		return 0;
	}
	optind++;
	length = cvtnum(blocksize, sectsize, argv[optind]);
	if (length < 0) {
		printf(_("non-numeric length argument -- %s\n"),
			argv[optind]);
		return 0;
	}

	if (sync_file_range(file->fd, offset, length, sync_mode) < 0) {
		perror("sync_file_range");
		return 0;
	}
	return 0;
}

void
sync_range_init(void)
{
	sync_range_cmd.name = "sync_range";
	sync_range_cmd.cfunc = sync_range_f;
	sync_range_cmd.argmin = 2;
	sync_range_cmd.argmax = -1;
	sync_range_cmd.flags = CMD_NOMAP_OK | CMD_FOREIGN_OK;
	sync_range_cmd.args = _("[-abw] off len");
	sync_range_cmd.oneline = _("Control writeback on a range of a file");
	sync_range_cmd.help = sync_range_help;

	add_command(&sync_range_cmd);
}