mirror of
https://github.com/AuxXxilium/linux_dsm_epyc7002.git
synced 2024-12-05 23:36:40 +07:00
bd55597520
NB: do we want btrfs_wait_ordered_range() on eviction of inodes with positive i_nlink on subvolume with zero root_refs? If not, btrfs_evict_inode() can be simplified by unconditionally bailing out in case of i_nlink > 0 in the very beginning... Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
900 lines
22 KiB
C
900 lines
22 KiB
C
/*
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* Copyright (C) 2007 Oracle. All rights reserved.
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*
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* This program is free software; you can redistribute it and/or
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* modify it under the terms of the GNU General Public
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* License v2 as published by the Free Software Foundation.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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* General Public License for more details.
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*
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* You should have received a copy of the GNU General Public
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* License along with this program; if not, write to the
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* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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* Boston, MA 021110-1307, USA.
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*/
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#include <linux/blkdev.h>
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#include <linux/module.h>
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#include <linux/buffer_head.h>
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#include <linux/fs.h>
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#include <linux/pagemap.h>
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#include <linux/highmem.h>
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#include <linux/time.h>
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#include <linux/init.h>
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#include <linux/seq_file.h>
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#include <linux/string.h>
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#include <linux/backing-dev.h>
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#include <linux/mount.h>
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#include <linux/mpage.h>
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#include <linux/swap.h>
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#include <linux/writeback.h>
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#include <linux/statfs.h>
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#include <linux/compat.h>
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#include <linux/parser.h>
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#include <linux/ctype.h>
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#include <linux/namei.h>
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#include <linux/miscdevice.h>
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#include <linux/magic.h>
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#include <linux/slab.h>
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#include "compat.h"
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#include "ctree.h"
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#include "disk-io.h"
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#include "transaction.h"
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#include "btrfs_inode.h"
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#include "ioctl.h"
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#include "print-tree.h"
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#include "xattr.h"
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#include "volumes.h"
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#include "version.h"
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#include "export.h"
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#include "compression.h"
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static const struct super_operations btrfs_super_ops;
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static void btrfs_put_super(struct super_block *sb)
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{
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struct btrfs_root *root = btrfs_sb(sb);
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int ret;
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ret = close_ctree(root);
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sb->s_fs_info = NULL;
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}
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enum {
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Opt_degraded, Opt_subvol, Opt_subvolid, Opt_device, Opt_nodatasum,
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Opt_nodatacow, Opt_max_inline, Opt_alloc_start, Opt_nobarrier, Opt_ssd,
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Opt_nossd, Opt_ssd_spread, Opt_thread_pool, Opt_noacl, Opt_compress,
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Opt_compress_force, Opt_notreelog, Opt_ratio, Opt_flushoncommit,
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Opt_discard, Opt_err,
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};
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static match_table_t tokens = {
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{Opt_degraded, "degraded"},
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{Opt_subvol, "subvol=%s"},
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{Opt_subvolid, "subvolid=%d"},
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{Opt_device, "device=%s"},
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{Opt_nodatasum, "nodatasum"},
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{Opt_nodatacow, "nodatacow"},
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{Opt_nobarrier, "nobarrier"},
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{Opt_max_inline, "max_inline=%s"},
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{Opt_alloc_start, "alloc_start=%s"},
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{Opt_thread_pool, "thread_pool=%d"},
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{Opt_compress, "compress"},
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{Opt_compress_force, "compress-force"},
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{Opt_ssd, "ssd"},
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{Opt_ssd_spread, "ssd_spread"},
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{Opt_nossd, "nossd"},
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{Opt_noacl, "noacl"},
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{Opt_notreelog, "notreelog"},
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{Opt_flushoncommit, "flushoncommit"},
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{Opt_ratio, "metadata_ratio=%d"},
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{Opt_discard, "discard"},
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{Opt_err, NULL},
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};
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/*
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* Regular mount options parser. Everything that is needed only when
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* reading in a new superblock is parsed here.
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*/
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int btrfs_parse_options(struct btrfs_root *root, char *options)
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{
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struct btrfs_fs_info *info = root->fs_info;
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substring_t args[MAX_OPT_ARGS];
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char *p, *num, *orig;
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int intarg;
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int ret = 0;
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if (!options)
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return 0;
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/*
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* strsep changes the string, duplicate it because parse_options
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* gets called twice
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*/
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options = kstrdup(options, GFP_NOFS);
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if (!options)
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return -ENOMEM;
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orig = options;
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while ((p = strsep(&options, ",")) != NULL) {
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int token;
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if (!*p)
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continue;
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token = match_token(p, tokens, args);
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switch (token) {
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case Opt_degraded:
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printk(KERN_INFO "btrfs: allowing degraded mounts\n");
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btrfs_set_opt(info->mount_opt, DEGRADED);
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break;
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case Opt_subvol:
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case Opt_subvolid:
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case Opt_device:
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/*
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* These are parsed by btrfs_parse_early_options
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* and can be happily ignored here.
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*/
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break;
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case Opt_nodatasum:
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printk(KERN_INFO "btrfs: setting nodatasum\n");
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btrfs_set_opt(info->mount_opt, NODATASUM);
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break;
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case Opt_nodatacow:
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printk(KERN_INFO "btrfs: setting nodatacow\n");
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btrfs_set_opt(info->mount_opt, NODATACOW);
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btrfs_set_opt(info->mount_opt, NODATASUM);
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break;
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case Opt_compress:
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printk(KERN_INFO "btrfs: use compression\n");
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btrfs_set_opt(info->mount_opt, COMPRESS);
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break;
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case Opt_compress_force:
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printk(KERN_INFO "btrfs: forcing compression\n");
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btrfs_set_opt(info->mount_opt, FORCE_COMPRESS);
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btrfs_set_opt(info->mount_opt, COMPRESS);
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break;
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case Opt_ssd:
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printk(KERN_INFO "btrfs: use ssd allocation scheme\n");
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btrfs_set_opt(info->mount_opt, SSD);
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break;
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case Opt_ssd_spread:
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printk(KERN_INFO "btrfs: use spread ssd "
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"allocation scheme\n");
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btrfs_set_opt(info->mount_opt, SSD);
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btrfs_set_opt(info->mount_opt, SSD_SPREAD);
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break;
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case Opt_nossd:
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printk(KERN_INFO "btrfs: not using ssd allocation "
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"scheme\n");
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btrfs_set_opt(info->mount_opt, NOSSD);
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btrfs_clear_opt(info->mount_opt, SSD);
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btrfs_clear_opt(info->mount_opt, SSD_SPREAD);
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break;
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case Opt_nobarrier:
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printk(KERN_INFO "btrfs: turning off barriers\n");
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btrfs_set_opt(info->mount_opt, NOBARRIER);
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break;
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case Opt_thread_pool:
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intarg = 0;
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match_int(&args[0], &intarg);
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if (intarg) {
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info->thread_pool_size = intarg;
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printk(KERN_INFO "btrfs: thread pool %d\n",
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info->thread_pool_size);
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}
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break;
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case Opt_max_inline:
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num = match_strdup(&args[0]);
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if (num) {
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info->max_inline = memparse(num, NULL);
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kfree(num);
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if (info->max_inline) {
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info->max_inline = max_t(u64,
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info->max_inline,
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root->sectorsize);
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}
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printk(KERN_INFO "btrfs: max_inline at %llu\n",
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(unsigned long long)info->max_inline);
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}
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break;
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case Opt_alloc_start:
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num = match_strdup(&args[0]);
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if (num) {
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info->alloc_start = memparse(num, NULL);
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kfree(num);
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printk(KERN_INFO
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"btrfs: allocations start at %llu\n",
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(unsigned long long)info->alloc_start);
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}
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break;
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case Opt_noacl:
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root->fs_info->sb->s_flags &= ~MS_POSIXACL;
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break;
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case Opt_notreelog:
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printk(KERN_INFO "btrfs: disabling tree log\n");
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btrfs_set_opt(info->mount_opt, NOTREELOG);
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break;
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case Opt_flushoncommit:
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printk(KERN_INFO "btrfs: turning on flush-on-commit\n");
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btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT);
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break;
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case Opt_ratio:
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intarg = 0;
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match_int(&args[0], &intarg);
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if (intarg) {
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info->metadata_ratio = intarg;
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printk(KERN_INFO "btrfs: metadata ratio %d\n",
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info->metadata_ratio);
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}
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break;
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case Opt_discard:
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btrfs_set_opt(info->mount_opt, DISCARD);
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break;
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case Opt_err:
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printk(KERN_INFO "btrfs: unrecognized mount option "
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"'%s'\n", p);
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ret = -EINVAL;
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goto out;
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default:
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break;
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}
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}
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out:
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kfree(orig);
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return ret;
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}
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/*
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* Parse mount options that are required early in the mount process.
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*
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* All other options will be parsed on much later in the mount process and
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* only when we need to allocate a new super block.
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*/
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static int btrfs_parse_early_options(const char *options, fmode_t flags,
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void *holder, char **subvol_name, u64 *subvol_objectid,
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struct btrfs_fs_devices **fs_devices)
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{
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substring_t args[MAX_OPT_ARGS];
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char *opts, *p;
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int error = 0;
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int intarg;
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if (!options)
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goto out;
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/*
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* strsep changes the string, duplicate it because parse_options
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* gets called twice
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*/
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opts = kstrdup(options, GFP_KERNEL);
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if (!opts)
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return -ENOMEM;
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while ((p = strsep(&opts, ",")) != NULL) {
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int token;
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if (!*p)
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continue;
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token = match_token(p, tokens, args);
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switch (token) {
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case Opt_subvol:
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*subvol_name = match_strdup(&args[0]);
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break;
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case Opt_subvolid:
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intarg = 0;
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error = match_int(&args[0], &intarg);
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if (!error) {
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/* we want the original fs_tree */
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if (!intarg)
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*subvol_objectid =
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BTRFS_FS_TREE_OBJECTID;
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else
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*subvol_objectid = intarg;
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}
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break;
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case Opt_device:
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error = btrfs_scan_one_device(match_strdup(&args[0]),
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flags, holder, fs_devices);
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if (error)
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goto out_free_opts;
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break;
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default:
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break;
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}
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}
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out_free_opts:
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kfree(opts);
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out:
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/*
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* If no subvolume name is specified we use the default one. Allocate
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* a copy of the string "." here so that code later in the
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* mount path doesn't care if it's the default volume or another one.
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*/
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if (!*subvol_name) {
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*subvol_name = kstrdup(".", GFP_KERNEL);
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if (!*subvol_name)
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return -ENOMEM;
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}
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return error;
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}
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static struct dentry *get_default_root(struct super_block *sb,
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u64 subvol_objectid)
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{
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struct btrfs_root *root = sb->s_fs_info;
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struct btrfs_root *new_root;
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struct btrfs_dir_item *di;
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struct btrfs_path *path;
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struct btrfs_key location;
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struct inode *inode;
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struct dentry *dentry;
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u64 dir_id;
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int new = 0;
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/*
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* We have a specific subvol we want to mount, just setup location and
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* go look up the root.
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*/
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if (subvol_objectid) {
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location.objectid = subvol_objectid;
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location.type = BTRFS_ROOT_ITEM_KEY;
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location.offset = (u64)-1;
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goto find_root;
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}
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path = btrfs_alloc_path();
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if (!path)
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return ERR_PTR(-ENOMEM);
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path->leave_spinning = 1;
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/*
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* Find the "default" dir item which points to the root item that we
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* will mount by default if we haven't been given a specific subvolume
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* to mount.
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*/
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dir_id = btrfs_super_root_dir(&root->fs_info->super_copy);
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di = btrfs_lookup_dir_item(NULL, root, path, dir_id, "default", 7, 0);
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if (IS_ERR(di))
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return ERR_CAST(di);
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if (!di) {
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/*
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* Ok the default dir item isn't there. This is weird since
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* it's always been there, but don't freak out, just try and
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* mount to root most subvolume.
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*/
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btrfs_free_path(path);
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dir_id = BTRFS_FIRST_FREE_OBJECTID;
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new_root = root->fs_info->fs_root;
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goto setup_root;
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}
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btrfs_dir_item_key_to_cpu(path->nodes[0], di, &location);
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btrfs_free_path(path);
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find_root:
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new_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
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if (IS_ERR(new_root))
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return ERR_PTR(PTR_ERR(new_root));
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if (btrfs_root_refs(&new_root->root_item) == 0)
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return ERR_PTR(-ENOENT);
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dir_id = btrfs_root_dirid(&new_root->root_item);
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setup_root:
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location.objectid = dir_id;
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location.type = BTRFS_INODE_ITEM_KEY;
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location.offset = 0;
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inode = btrfs_iget(sb, &location, new_root, &new);
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if (IS_ERR(inode))
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return ERR_CAST(inode);
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/*
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* If we're just mounting the root most subvol put the inode and return
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* a reference to the dentry. We will have already gotten a reference
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* to the inode in btrfs_fill_super so we're good to go.
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*/
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if (!new && sb->s_root->d_inode == inode) {
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iput(inode);
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return dget(sb->s_root);
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}
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if (new) {
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const struct qstr name = { .name = "/", .len = 1 };
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/*
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* New inode, we need to make the dentry a sibling of s_root so
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* everything gets cleaned up properly on unmount.
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*/
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dentry = d_alloc(sb->s_root, &name);
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if (!dentry) {
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iput(inode);
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return ERR_PTR(-ENOMEM);
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}
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d_splice_alias(inode, dentry);
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} else {
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/*
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* We found the inode in cache, just find a dentry for it and
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* put the reference to the inode we just got.
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*/
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dentry = d_find_alias(inode);
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iput(inode);
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}
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return dentry;
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}
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static int btrfs_fill_super(struct super_block *sb,
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struct btrfs_fs_devices *fs_devices,
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void *data, int silent)
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{
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struct inode *inode;
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struct dentry *root_dentry;
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struct btrfs_super_block *disk_super;
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struct btrfs_root *tree_root;
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struct btrfs_key key;
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int err;
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sb->s_maxbytes = MAX_LFS_FILESIZE;
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sb->s_magic = BTRFS_SUPER_MAGIC;
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sb->s_op = &btrfs_super_ops;
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sb->s_export_op = &btrfs_export_ops;
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sb->s_xattr = btrfs_xattr_handlers;
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sb->s_time_gran = 1;
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#ifdef CONFIG_BTRFS_FS_POSIX_ACL
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sb->s_flags |= MS_POSIXACL;
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#endif
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tree_root = open_ctree(sb, fs_devices, (char *)data);
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if (IS_ERR(tree_root)) {
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printk("btrfs: open_ctree failed\n");
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return PTR_ERR(tree_root);
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}
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sb->s_fs_info = tree_root;
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disk_super = &tree_root->fs_info->super_copy;
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key.objectid = BTRFS_FIRST_FREE_OBJECTID;
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key.type = BTRFS_INODE_ITEM_KEY;
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key.offset = 0;
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inode = btrfs_iget(sb, &key, tree_root->fs_info->fs_root, NULL);
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if (IS_ERR(inode)) {
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err = PTR_ERR(inode);
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goto fail_close;
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}
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root_dentry = d_alloc_root(inode);
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if (!root_dentry) {
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iput(inode);
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err = -ENOMEM;
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goto fail_close;
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}
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sb->s_root = root_dentry;
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save_mount_options(sb, data);
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return 0;
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fail_close:
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close_ctree(tree_root);
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return err;
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}
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int btrfs_sync_fs(struct super_block *sb, int wait)
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{
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struct btrfs_trans_handle *trans;
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struct btrfs_root *root = btrfs_sb(sb);
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int ret;
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if (!wait) {
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filemap_flush(root->fs_info->btree_inode->i_mapping);
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return 0;
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}
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btrfs_start_delalloc_inodes(root, 0);
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btrfs_wait_ordered_extents(root, 0, 0);
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trans = btrfs_start_transaction(root, 0);
|
|
ret = btrfs_commit_transaction(trans, root);
|
|
return ret;
|
|
}
|
|
|
|
static int btrfs_show_options(struct seq_file *seq, struct vfsmount *vfs)
|
|
{
|
|
struct btrfs_root *root = btrfs_sb(vfs->mnt_sb);
|
|
struct btrfs_fs_info *info = root->fs_info;
|
|
|
|
if (btrfs_test_opt(root, DEGRADED))
|
|
seq_puts(seq, ",degraded");
|
|
if (btrfs_test_opt(root, NODATASUM))
|
|
seq_puts(seq, ",nodatasum");
|
|
if (btrfs_test_opt(root, NODATACOW))
|
|
seq_puts(seq, ",nodatacow");
|
|
if (btrfs_test_opt(root, NOBARRIER))
|
|
seq_puts(seq, ",nobarrier");
|
|
if (info->max_inline != 8192 * 1024)
|
|
seq_printf(seq, ",max_inline=%llu",
|
|
(unsigned long long)info->max_inline);
|
|
if (info->alloc_start != 0)
|
|
seq_printf(seq, ",alloc_start=%llu",
|
|
(unsigned long long)info->alloc_start);
|
|
if (info->thread_pool_size != min_t(unsigned long,
|
|
num_online_cpus() + 2, 8))
|
|
seq_printf(seq, ",thread_pool=%d", info->thread_pool_size);
|
|
if (btrfs_test_opt(root, COMPRESS))
|
|
seq_puts(seq, ",compress");
|
|
if (btrfs_test_opt(root, NOSSD))
|
|
seq_puts(seq, ",nossd");
|
|
if (btrfs_test_opt(root, SSD_SPREAD))
|
|
seq_puts(seq, ",ssd_spread");
|
|
else if (btrfs_test_opt(root, SSD))
|
|
seq_puts(seq, ",ssd");
|
|
if (btrfs_test_opt(root, NOTREELOG))
|
|
seq_puts(seq, ",notreelog");
|
|
if (btrfs_test_opt(root, FLUSHONCOMMIT))
|
|
seq_puts(seq, ",flushoncommit");
|
|
if (btrfs_test_opt(root, DISCARD))
|
|
seq_puts(seq, ",discard");
|
|
if (!(root->fs_info->sb->s_flags & MS_POSIXACL))
|
|
seq_puts(seq, ",noacl");
|
|
return 0;
|
|
}
|
|
|
|
static int btrfs_test_super(struct super_block *s, void *data)
|
|
{
|
|
struct btrfs_fs_devices *test_fs_devices = data;
|
|
struct btrfs_root *root = btrfs_sb(s);
|
|
|
|
return root->fs_info->fs_devices == test_fs_devices;
|
|
}
|
|
|
|
/*
|
|
* Find a superblock for the given device / mount point.
|
|
*
|
|
* Note: This is based on get_sb_bdev from fs/super.c with a few additions
|
|
* for multiple device setup. Make sure to keep it in sync.
|
|
*/
|
|
static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
|
|
const char *dev_name, void *data, struct vfsmount *mnt)
|
|
{
|
|
struct block_device *bdev = NULL;
|
|
struct super_block *s;
|
|
struct dentry *root;
|
|
struct btrfs_fs_devices *fs_devices = NULL;
|
|
fmode_t mode = FMODE_READ;
|
|
char *subvol_name = NULL;
|
|
u64 subvol_objectid = 0;
|
|
int error = 0;
|
|
int found = 0;
|
|
|
|
if (!(flags & MS_RDONLY))
|
|
mode |= FMODE_WRITE;
|
|
|
|
error = btrfs_parse_early_options(data, mode, fs_type,
|
|
&subvol_name, &subvol_objectid,
|
|
&fs_devices);
|
|
if (error)
|
|
return error;
|
|
|
|
error = btrfs_scan_one_device(dev_name, mode, fs_type, &fs_devices);
|
|
if (error)
|
|
goto error_free_subvol_name;
|
|
|
|
error = btrfs_open_devices(fs_devices, mode, fs_type);
|
|
if (error)
|
|
goto error_free_subvol_name;
|
|
|
|
if (!(flags & MS_RDONLY) && fs_devices->rw_devices == 0) {
|
|
error = -EACCES;
|
|
goto error_close_devices;
|
|
}
|
|
|
|
bdev = fs_devices->latest_bdev;
|
|
s = sget(fs_type, btrfs_test_super, set_anon_super, fs_devices);
|
|
if (IS_ERR(s))
|
|
goto error_s;
|
|
|
|
if (s->s_root) {
|
|
if ((flags ^ s->s_flags) & MS_RDONLY) {
|
|
deactivate_locked_super(s);
|
|
error = -EBUSY;
|
|
goto error_close_devices;
|
|
}
|
|
|
|
found = 1;
|
|
btrfs_close_devices(fs_devices);
|
|
} else {
|
|
char b[BDEVNAME_SIZE];
|
|
|
|
s->s_flags = flags;
|
|
strlcpy(s->s_id, bdevname(bdev, b), sizeof(s->s_id));
|
|
error = btrfs_fill_super(s, fs_devices, data,
|
|
flags & MS_SILENT ? 1 : 0);
|
|
if (error) {
|
|
deactivate_locked_super(s);
|
|
goto error_free_subvol_name;
|
|
}
|
|
|
|
btrfs_sb(s)->fs_info->bdev_holder = fs_type;
|
|
s->s_flags |= MS_ACTIVE;
|
|
}
|
|
|
|
root = get_default_root(s, subvol_objectid);
|
|
if (IS_ERR(root)) {
|
|
error = PTR_ERR(root);
|
|
deactivate_locked_super(s);
|
|
goto error;
|
|
}
|
|
/* if they gave us a subvolume name bind mount into that */
|
|
if (strcmp(subvol_name, ".")) {
|
|
struct dentry *new_root;
|
|
mutex_lock(&root->d_inode->i_mutex);
|
|
new_root = lookup_one_len(subvol_name, root,
|
|
strlen(subvol_name));
|
|
mutex_unlock(&root->d_inode->i_mutex);
|
|
|
|
if (IS_ERR(new_root)) {
|
|
deactivate_locked_super(s);
|
|
error = PTR_ERR(new_root);
|
|
dput(root);
|
|
goto error_close_devices;
|
|
}
|
|
if (!new_root->d_inode) {
|
|
dput(root);
|
|
dput(new_root);
|
|
deactivate_locked_super(s);
|
|
error = -ENXIO;
|
|
goto error_close_devices;
|
|
}
|
|
dput(root);
|
|
root = new_root;
|
|
}
|
|
|
|
mnt->mnt_sb = s;
|
|
mnt->mnt_root = root;
|
|
|
|
kfree(subvol_name);
|
|
return 0;
|
|
|
|
error_s:
|
|
error = PTR_ERR(s);
|
|
error_close_devices:
|
|
btrfs_close_devices(fs_devices);
|
|
error_free_subvol_name:
|
|
kfree(subvol_name);
|
|
error:
|
|
return error;
|
|
}
|
|
|
|
static int btrfs_remount(struct super_block *sb, int *flags, char *data)
|
|
{
|
|
struct btrfs_root *root = btrfs_sb(sb);
|
|
int ret;
|
|
|
|
ret = btrfs_parse_options(root, data);
|
|
if (ret)
|
|
return -EINVAL;
|
|
|
|
if ((*flags & MS_RDONLY) == (sb->s_flags & MS_RDONLY))
|
|
return 0;
|
|
|
|
if (*flags & MS_RDONLY) {
|
|
sb->s_flags |= MS_RDONLY;
|
|
|
|
ret = btrfs_commit_super(root);
|
|
WARN_ON(ret);
|
|
} else {
|
|
if (root->fs_info->fs_devices->rw_devices == 0)
|
|
return -EACCES;
|
|
|
|
if (btrfs_super_log_root(&root->fs_info->super_copy) != 0)
|
|
return -EINVAL;
|
|
|
|
ret = btrfs_cleanup_fs_roots(root->fs_info);
|
|
WARN_ON(ret);
|
|
|
|
/* recover relocation */
|
|
ret = btrfs_recover_relocation(root);
|
|
WARN_ON(ret);
|
|
|
|
sb->s_flags &= ~MS_RDONLY;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
static int btrfs_statfs(struct dentry *dentry, struct kstatfs *buf)
|
|
{
|
|
struct btrfs_root *root = btrfs_sb(dentry->d_sb);
|
|
struct btrfs_super_block *disk_super = &root->fs_info->super_copy;
|
|
struct list_head *head = &root->fs_info->space_info;
|
|
struct btrfs_space_info *found;
|
|
u64 total_used = 0;
|
|
int bits = dentry->d_sb->s_blocksize_bits;
|
|
__be32 *fsid = (__be32 *)root->fs_info->fsid;
|
|
|
|
rcu_read_lock();
|
|
list_for_each_entry_rcu(found, head, list)
|
|
total_used += found->disk_used;
|
|
rcu_read_unlock();
|
|
|
|
buf->f_namelen = BTRFS_NAME_LEN;
|
|
buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits;
|
|
buf->f_bfree = buf->f_blocks - (total_used >> bits);
|
|
buf->f_bavail = buf->f_bfree;
|
|
buf->f_bsize = dentry->d_sb->s_blocksize;
|
|
buf->f_type = BTRFS_SUPER_MAGIC;
|
|
|
|
/* We treat it as constant endianness (it doesn't matter _which_)
|
|
because we want the fsid to come out the same whether mounted
|
|
on a big-endian or little-endian host */
|
|
buf->f_fsid.val[0] = be32_to_cpu(fsid[0]) ^ be32_to_cpu(fsid[2]);
|
|
buf->f_fsid.val[1] = be32_to_cpu(fsid[1]) ^ be32_to_cpu(fsid[3]);
|
|
/* Mask in the root object ID too, to disambiguate subvols */
|
|
buf->f_fsid.val[0] ^= BTRFS_I(dentry->d_inode)->root->objectid >> 32;
|
|
buf->f_fsid.val[1] ^= BTRFS_I(dentry->d_inode)->root->objectid;
|
|
|
|
return 0;
|
|
}
|
|
|
|
static struct file_system_type btrfs_fs_type = {
|
|
.owner = THIS_MODULE,
|
|
.name = "btrfs",
|
|
.get_sb = btrfs_get_sb,
|
|
.kill_sb = kill_anon_super,
|
|
.fs_flags = FS_REQUIRES_DEV,
|
|
};
|
|
|
|
/*
|
|
* used by btrfsctl to scan devices when no FS is mounted
|
|
*/
|
|
static long btrfs_control_ioctl(struct file *file, unsigned int cmd,
|
|
unsigned long arg)
|
|
{
|
|
struct btrfs_ioctl_vol_args *vol;
|
|
struct btrfs_fs_devices *fs_devices;
|
|
int ret = -ENOTTY;
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
return -EPERM;
|
|
|
|
vol = memdup_user((void __user *)arg, sizeof(*vol));
|
|
if (IS_ERR(vol))
|
|
return PTR_ERR(vol);
|
|
|
|
switch (cmd) {
|
|
case BTRFS_IOC_SCAN_DEV:
|
|
ret = btrfs_scan_one_device(vol->name, FMODE_READ,
|
|
&btrfs_fs_type, &fs_devices);
|
|
break;
|
|
}
|
|
|
|
kfree(vol);
|
|
return ret;
|
|
}
|
|
|
|
static int btrfs_freeze(struct super_block *sb)
|
|
{
|
|
struct btrfs_root *root = btrfs_sb(sb);
|
|
mutex_lock(&root->fs_info->transaction_kthread_mutex);
|
|
mutex_lock(&root->fs_info->cleaner_mutex);
|
|
return 0;
|
|
}
|
|
|
|
static int btrfs_unfreeze(struct super_block *sb)
|
|
{
|
|
struct btrfs_root *root = btrfs_sb(sb);
|
|
mutex_unlock(&root->fs_info->cleaner_mutex);
|
|
mutex_unlock(&root->fs_info->transaction_kthread_mutex);
|
|
return 0;
|
|
}
|
|
|
|
static const struct super_operations btrfs_super_ops = {
|
|
.drop_inode = btrfs_drop_inode,
|
|
.evict_inode = btrfs_evict_inode,
|
|
.put_super = btrfs_put_super,
|
|
.sync_fs = btrfs_sync_fs,
|
|
.show_options = btrfs_show_options,
|
|
.write_inode = btrfs_write_inode,
|
|
.dirty_inode = btrfs_dirty_inode,
|
|
.alloc_inode = btrfs_alloc_inode,
|
|
.destroy_inode = btrfs_destroy_inode,
|
|
.statfs = btrfs_statfs,
|
|
.remount_fs = btrfs_remount,
|
|
.freeze_fs = btrfs_freeze,
|
|
.unfreeze_fs = btrfs_unfreeze,
|
|
};
|
|
|
|
static const struct file_operations btrfs_ctl_fops = {
|
|
.unlocked_ioctl = btrfs_control_ioctl,
|
|
.compat_ioctl = btrfs_control_ioctl,
|
|
.owner = THIS_MODULE,
|
|
};
|
|
|
|
static struct miscdevice btrfs_misc = {
|
|
.minor = BTRFS_MINOR,
|
|
.name = "btrfs-control",
|
|
.fops = &btrfs_ctl_fops
|
|
};
|
|
|
|
MODULE_ALIAS_MISCDEV(BTRFS_MINOR);
|
|
MODULE_ALIAS("devname:btrfs-control");
|
|
|
|
static int btrfs_interface_init(void)
|
|
{
|
|
return misc_register(&btrfs_misc);
|
|
}
|
|
|
|
static void btrfs_interface_exit(void)
|
|
{
|
|
if (misc_deregister(&btrfs_misc) < 0)
|
|
printk(KERN_INFO "misc_deregister failed for control device");
|
|
}
|
|
|
|
static int __init init_btrfs_fs(void)
|
|
{
|
|
int err;
|
|
|
|
err = btrfs_init_sysfs();
|
|
if (err)
|
|
return err;
|
|
|
|
err = btrfs_init_cachep();
|
|
if (err)
|
|
goto free_sysfs;
|
|
|
|
err = extent_io_init();
|
|
if (err)
|
|
goto free_cachep;
|
|
|
|
err = extent_map_init();
|
|
if (err)
|
|
goto free_extent_io;
|
|
|
|
err = btrfs_interface_init();
|
|
if (err)
|
|
goto free_extent_map;
|
|
|
|
err = register_filesystem(&btrfs_fs_type);
|
|
if (err)
|
|
goto unregister_ioctl;
|
|
|
|
printk(KERN_INFO "%s loaded\n", BTRFS_BUILD_VERSION);
|
|
return 0;
|
|
|
|
unregister_ioctl:
|
|
btrfs_interface_exit();
|
|
free_extent_map:
|
|
extent_map_exit();
|
|
free_extent_io:
|
|
extent_io_exit();
|
|
free_cachep:
|
|
btrfs_destroy_cachep();
|
|
free_sysfs:
|
|
btrfs_exit_sysfs();
|
|
return err;
|
|
}
|
|
|
|
static void __exit exit_btrfs_fs(void)
|
|
{
|
|
btrfs_destroy_cachep();
|
|
extent_map_exit();
|
|
extent_io_exit();
|
|
btrfs_interface_exit();
|
|
unregister_filesystem(&btrfs_fs_type);
|
|
btrfs_exit_sysfs();
|
|
btrfs_cleanup_fs_uuids();
|
|
btrfs_zlib_exit();
|
|
}
|
|
|
|
module_init(init_btrfs_fs)
|
|
module_exit(exit_btrfs_fs)
|
|
|
|
MODULE_LICENSE("GPL");
|