path: root/fs/btrfs/super.c

/*
 * Copyright (C) 2007 Oracle.  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 v2 as published by the Free Software Foundation.
 *
 * 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 021110-1307, USA.
 */

#include <linux/blkdev.h>
#include <linux/module.h>
#include <linux/buffer_head.h>
#include <linux/fs.h>
#include <linux/pagemap.h>
#include <linux/highmem.h>
#include <linux/time.h>
#include <linux/init.h>
#include <linux/seq_file.h>
#include <linux/string.h>
#include <linux/backing-dev.h>
#include <linux/mount.h>
#include <linux/mpage.h>
#include <linux/swap.h>
#include <linux/writeback.h>
#include <linux/statfs.h>
#include <linux/compat.h>
#include <linux/parser.h>
#include <linux/ctype.h>
#include <linux/namei.h>
#include <linux/miscdevice.h>
#include <linux/magic.h>
#include "compat.h"
#include "ctree.h"
#include "disk-io.h"
#include "transaction.h"
#include "btrfs_inode.h"
#include "ioctl.h"
#include "print-tree.h"
#include "xattr.h"
#include "volumes.h"
#include "version.h"
#include "export.h"
#include "compression.h"

static const struct super_operations btrfs_super_ops;

static void btrfs_put_super(struct super_block *sb)
{
	struct btrfs_root *root = btrfs_sb(sb);
	int ret;

	ret = close_ctree(root);
	sb->s_fs_info = NULL;
}

enum {
	Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum,
	Opt_nodatacow, Opt_max_extent, Opt_max_inline, Opt_alloc_start,
	Opt_nobarrier, Opt_ssd, Opt_nossd, Opt_ssd_spread, Opt_thread_pool,
	Opt_noacl, Opt_compress, Opt_compress_force, Opt_notreelog, Opt_ratio,
	Opt_flushoncommit,
	Opt_discard, Opt_err,
};

static match_table_t tokens = {
	{Opt_degraded, "degraded"},
	{Opt_subvol, "subvol=%s"},
	{Opt_subvolid, "subvolid=%d"},
	{Opt_device, "device=%s"},
	{Opt_nodatasum, "nodatasum"},
	{Opt_nodatacow, "nodatacow"},
	{Opt_nobarrier, "nobarrier"},
	{Opt_max_extent, "max_extent=%s"},
	{Opt_max_inline, "max_inline=%s"},
	{Opt_alloc_start, "alloc_start=%s"},
	{Opt_thread_pool, "thread_pool=%d"},
	{Opt_compress, "compress"},
	{Opt_compress_force, "compress-force"},
	{Opt_ssd, "ssd"},
	{Opt_ssd_spread, "ssd_spread"},
	{Opt_nossd, "nossd"},
	{Opt_noacl, "noacl"},
	{Opt_notreelog, "notreelog"},
	{Opt_flushoncommit, "flushoncommit"},
	{Opt_ratio, "metadata_ratio=%d"},
	{Opt_discard, "discard"},
	{Opt_err, NULL},
};

u64 btrfs_parse_size(char *str)
{
	u64 res;
	int mult = 1;
	char *end;
	char last;

	res = simple_strtoul(str, &end, 10);

	last = end[0];
	if (isalpha(last)) {
		last = tolower(last);
		switch (last) {
		case 'g':
			mult *= 1024;
		case 'm':
			mult *= 1024;
		case 'k':
			mult *= 1024;
		}
		res = res * mult;
	}
	return res;
}

/*
 * Regular mount options parser.  Everything that is needed only when
 * reading in a new superblock is parsed here.
 */
int btrfs_parse_options(struct btrfs_root *root, char *options)
{
	struct btrfs_fs_info *info = root->fs_info;
	substring_t args[MAX_OPT_ARGS];
	char *p, *num, *orig;
	int intarg;
	int ret = 0;

	if (!options)
		return 0;

	/*
	 * strsep changes the string, duplicate it because parse_options
	 * gets called twice
	 */
	options = kstrdup(options, GFP_NOFS);
	if (!options)
		return -ENOMEM;

	orig = options;

	while ((p = strsep(&options, ",")) != NULL) {
		int token;
		if (!*p)
			continue;

		token = match_token(p, tokens, args);
		switch (token) {
		case Opt_degraded:
			printk(KERN_INFO "btrfs: allowing degraded mounts\n");
			btrfs_set_opt(info->mount_opt, DEGRADED);
			break;
		case Opt_subvol:
		case Opt_subvolid:
		case Opt_device:
			/*
			 * These are parsed by btrfs_parse_early_options
			 * and can be happily ignored here.
			 */
			break;
		case Opt_nodatasum:
			printk(KERN_INFO "btrfs: setting nodatasum\n");
			btrfs_set_opt(info->mount_opt, NODATASUM);
			break;
		case Opt_nodatacow:
			printk(KERN_INFO "btrfs: setting nodatacow\n");
			btrfs_set_opt(info->mount_opt, NODATACOW);
			btrfs_set_opt(info->mount_opt, NODATASUM);
			break;
		case Opt_compress: