![Josef Bacik](/assets/img/avatar_default.png)
This patch makes the chunk allocator keep a good ratio of metadata vs data block groups. By default for every 8 data block groups, we'll allocate 1 metadata chunk, or about 12% of the disk will be allocated for metadata. This can be changed by specifying the metadata_ratio mount option. This is simply the number of data block groups that have to be allocated to force a metadata chunk allocation. By making sure we allocate metadata chunks more often, we are less likely to get into situations where the whole disk has been allocated as data block groups. Signed-off-by: Josef Bacik <jbacik@redhat.com> Signed-off-by: Chris Mason <chris.mason@oracle.com>
783 lines
18 KiB
C
783 lines
18 KiB
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/smp_lock.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 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_device, Opt_nodatasum, Opt_nodatacow,
|
|
Opt_max_extent, Opt_max_inline, Opt_alloc_start, Opt_nobarrier,
|
|
Opt_ssd, Opt_thread_pool, Opt_noacl, Opt_compress, Opt_notreelog,
|
|
Opt_ratio, Opt_flushoncommit, Opt_err,
|
|
};
|
|
|
|
static match_table_t tokens = {
|
|
{Opt_degraded, "degraded"},
|
|
{Opt_subvol, "subvol=%s"},
|
|
{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_ssd, "ssd"},
|
|
{Opt_noacl, "noacl"},
|
|
{Opt_notreelog, "notreelog"},
|
|
{Opt_flushoncommit, "flushoncommit"},
|
|
{Opt_ratio, "metadata_ratio=%d"},
|
|
{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;
|
|
int intarg;
|
|
|
|
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;
|
|
|
|
|
|
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_device:
|
|
/*
|
|
* These are parsed by btrfs_parse_early_options
|
|
* and can be happily ignored here.
|
|
*/
|
|
break;
|
|
case Opt_nodatasum:
|
|
printk(KERN_INFO "btrfs: setting nodatacsum\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:
|
|
printk(KERN_INFO "btrfs: use compression\n");
|
|
btrfs_set_opt(info->mount_opt, COMPRESS);
|
|
break;
|
|
case Opt_ssd:
|
|
printk(KERN_INFO "btrfs: use ssd allocation scheme\n");
|
|
btrfs_set_opt(info->mount_opt, SSD);
|
|
break;
|
|
case Opt_nobarrier:
|
|
printk(KERN_INFO "btrfs: turning off barriers\n");
|
|
btrfs_set_opt(info->mount_opt, NOBARRIER);
|
|
break;
|
|
case Opt_thread_pool:
|
|
intarg = 0;
|
|
match_int(&args[0], &intarg);
|
|
if (intarg) {
|
|
info->thread_pool_size = intarg;
|
|
printk(KERN_INFO "btrfs: thread pool %d\n",
|
|
info->thread_pool_size);
|
|
}
|
|
break;
|
|
case Opt_max_extent:
|
|
num = match_strdup(&args[0]);
|
|
if (num) {
|
|
info->max_extent = btrfs_parse_size(num);
|
|
kfree(num);
|
|
|
|
info->max_extent = max_t(u64,
|
|
info->max_extent, root->sectorsize);
|
|
printk(KERN_INFO "btrfs: max_extent at %llu\n",
|
|
info->max_extent);
|
|
}
|
|
break;
|
|
case Opt_max_inline:
|
|
num = match_strdup(&args[0]);
|
|
if (num) {
|
|
info->max_inline = btrfs_parse_size(num);
|
|
kfree(num);
|
|
|
|
if (info->max_inline) {
|
|
info->max_inline = max_t(u64,
|
|
info->max_inline,
|
|
root->sectorsize);
|
|
}
|
|
printk(KERN_INFO "btrfs: max_inline at %llu\n",
|
|
info->max_inline);
|
|
}
|
|
break;
|
|
case Opt_alloc_start:
|
|
num = match_strdup(&args[0]);
|
|
if (num) {
|
|
info->alloc_start = btrfs_parse_size(num);
|
|
kfree(num);
|
|
printk(KERN_INFO
|
|
"btrfs: allocations start at %llu\n",
|
|
info->alloc_start);
|
|
}
|
|
break;
|
|
case Opt_noacl:
|
|
root->fs_info->sb->s_flags &= ~MS_POSIXACL;
|
|
break;
|
|
case Opt_notreelog:
|
|
printk(KERN_INFO "btrfs: disabling tree log\n");
|
|
btrfs_set_opt(info->mount_opt, NOTREELOG);
|
|
break;
|
|
case Opt_flushoncommit:
|
|
printk(KERN_INFO "btrfs: turning on flush-on-commit\n");
|
|
btrfs_set_opt(info->mount_opt, FLUSHONCOMMIT);
|
|
break;
|
|
case Opt_ratio:
|
|
intarg = 0;
|
|
match_int(&args[0], &intarg);
|
|
if (intarg) {
|
|
info->metadata_ratio = intarg;
|
|
printk(KERN_INFO "btrfs: metadata ratio %d\n",
|
|
info->metadata_ratio);
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
kfree(options);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Parse mount options that are required early in the mount process.
|
|
*
|
|
* All other options will be parsed on much later in the mount process and
|
|
* only when we need to allocate a new super block.
|
|
*/
|
|
static int btrfs_parse_early_options(const char *options, fmode_t flags,
|
|
void *holder, char **subvol_name,
|
|
struct btrfs_fs_devices **fs_devices)
|
|
{
|
|
substring_t args[MAX_OPT_ARGS];
|
|
char *opts, *p;
|
|
int error = 0;
|
|
|
|
if (!options)
|
|
goto out;
|
|
|
|
/*
|
|
* strsep changes the string, duplicate it because parse_options
|
|
* gets called twice
|
|
*/
|
|
opts = kstrdup(options, GFP_KERNEL);
|
|
if (!opts)
|
|
return -ENOMEM;
|
|
|
|
while ((p = strsep(&opts, ",")) != NULL) {
|
|
int token;
|
|
if (!*p)
|
|
continue;
|
|
|
|
token = match_token(p, tokens, args);
|
|
switch (token) {
|
|
case Opt_subvol:
|
|
*subvol_name = match_strdup(&args[0]);
|
|
break;
|
|
case Opt_device:
|
|
error = btrfs_scan_one_device(match_strdup(&args[0]),
|
|
flags, holder, fs_devices);
|
|
if (error)
|
|
goto out_free_opts;
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
out_free_opts:
|
|
kfree(opts);
|
|
out:
|
|
/*
|
|
* If no subvolume name is specified we use the default one. Allocate
|
|
* a copy of the string "." here so that code later in the
|
|
* mount path doesn't care if it's the default volume or another one.
|
|
*/
|
|
if (!*subvol_name) {
|
|
*subvol_name = kstrdup(".", GFP_KERNEL);
|
|
if (!*subvol_name)
|
|
return -ENOMEM;
|
|
}
|
|
return error;
|
|
}
|
|
|
|
static int btrfs_fill_super(struct super_block *sb,
|
|
struct btrfs_fs_devices *fs_devices,
|
|
void *data, int silent)
|
|
{
|
|
struct inode *inode;
|
|
struct dentry *root_dentry;
|
|
struct btrfs_super_block *disk_super;
|
|
struct btrfs_root *tree_root;
|
|
struct btrfs_inode *bi;
|
|
int err;
|
|
|
|
sb->s_maxbytes = MAX_LFS_FILESIZE;
|
|
sb->s_magic = BTRFS_SUPER_MAGIC;
|
|
sb->s_op = &btrfs_super_ops;
|
|
sb->s_export_op = &btrfs_export_ops;
|
|
sb->s_xattr = btrfs_xattr_handlers;
|
|
sb->s_time_gran = 1;
|
|
sb->s_flags |= MS_POSIXACL;
|
|
|
|
tree_root = open_ctree(sb, fs_devices, (char *)data);
|
|
|
|
if (IS_ERR(tree_root)) {
|
|
printk("btrfs: open_ctree failed\n");
|
|
return PTR_ERR(tree_root);
|
|
}
|
|
sb->s_fs_info = tree_root;
|
|
disk_super = &tree_root->fs_info->super_copy;
|
|
inode = btrfs_iget_locked(sb, BTRFS_FIRST_FREE_OBJECTID,
|
|
tree_root->fs_info->fs_root);
|
|
bi = BTRFS_I(inode);
|
|
bi->location.objectid = inode->i_ino;
|
|
bi->location.offset = 0;
|
|
bi->root = tree_root->fs_info->fs_root;
|
|
|
|
btrfs_set_key_type(&bi->location, BTRFS_INODE_ITEM_KEY);
|
|
|
|
if (!inode) {
|
|
err = -ENOMEM;
|
|
goto fail_close;
|
|
}
|
|
if (inode->i_state & I_NEW) {
|
|
btrfs_read_locked_inode(inode);
|
|
unlock_new_inode(inode);
|
|
}
|
|
|
|
root_dentry = d_alloc_root(inode);
|
|
if (!root_dentry) {
|
|
iput(inode);
|
|
err = -ENOMEM;
|
|
goto fail_close;
|
|
}
|
|
#if 0
|
|
/* this does the super kobj at the same time */
|
|
err = btrfs_sysfs_add_super(tree_root->fs_info);
|
|
if (err)
|
|
goto fail_close;
|
|
#endif
|
|
|
|
sb->s_root = root_dentry;
|
|
|
|
save_mount_options(sb, data);
|
|
return 0;
|
|
|
|
fail_close:
|
|
close_ctree(tree_root);
|
|
return err;
|
|
}
|
|
|
|
int btrfs_sync_fs(struct super_block *sb, int wait)
|
|
{
|
|
struct btrfs_trans_handle *trans;
|
|
struct btrfs_root *root = btrfs_sb(sb);
|
|
int ret;
|
|
|
|
if (sb->s_flags & MS_RDONLY)
|
|
return 0;
|
|
|
|
sb->s_dirt = 0;
|
|
if (!wait) {
|
|
filemap_flush(root->fs_info->btree_inode->i_mapping);
|
|
return 0;
|
|
}
|
|
|
|
btrfs_start_delalloc_inodes(root);
|
|
btrfs_wait_ordered_extents(root, 0);
|
|
|
|
trans = btrfs_start_transaction(root, 1);
|
|
ret = btrfs_commit_transaction(trans, root);
|
|
sb->s_dirt = 0;
|
|
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_extent != (u64)-1)
|
|
seq_printf(seq, ",max_extent=%llu", info->max_extent);
|
|
if (info->max_inline != 8192 * 1024)
|
|
seq_printf(seq, ",max_inline=%llu", info->max_inline);
|
|
if (info->alloc_start != 0)
|
|
seq_printf(seq, ",alloc_start=%llu", 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, SSD))
|
|
seq_puts(seq, ",ssd");
|
|
if (btrfs_test_opt(root, NOTREELOG))
|
|
seq_puts(seq, ",no-treelog");
|
|
if (btrfs_test_opt(root, FLUSHONCOMMIT))
|
|
seq_puts(seq, ",flush-on-commit");
|
|
if (!(root->fs_info->sb->s_flags & MS_POSIXACL))
|
|
seq_puts(seq, ",noacl");
|
|
return 0;
|
|
}
|
|
|
|
static void btrfs_write_super(struct super_block *sb)
|
|
{
|
|
sb->s_dirt = 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)
|
|
{
|
|
char *subvol_name = NULL;
|
|
struct block_device *bdev = NULL;
|
|
struct super_block *s;
|
|
struct dentry *root;
|
|
struct btrfs_fs_devices *fs_devices = NULL;
|
|
fmode_t mode = FMODE_READ;
|
|
int error = 0;
|
|
|
|
if (!(flags & MS_RDONLY))
|
|
mode |= FMODE_WRITE;
|
|
|
|
error = btrfs_parse_early_options(data, mode, fs_type,
|
|
&subvol_name, &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) {
|
|
up_write(&s->s_umount);
|
|
deactivate_super(s);
|
|
error = -EBUSY;
|
|
goto error_close_devices;
|
|
}
|
|
|
|
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) {
|
|
up_write(&s->s_umount);
|
|
deactivate_super(s);
|
|
goto error_free_subvol_name;
|
|
}
|
|
|
|
btrfs_sb(s)->fs_info->bdev_holder = fs_type;
|
|
s->s_flags |= MS_ACTIVE;
|
|
}
|
|
|
|
if (!strcmp(subvol_name, "."))
|
|
root = dget(s->s_root);
|
|
else {
|
|
mutex_lock(&s->s_root->d_inode->i_mutex);
|
|
root = lookup_one_len(subvol_name, s->s_root,
|
|
strlen(subvol_name));
|
|
mutex_unlock(&s->s_root->d_inode->i_mutex);
|
|
|
|
if (IS_ERR(root)) {
|
|
up_write(&s->s_umount);
|
|
deactivate_super(s);
|
|
error = PTR_ERR(root);
|
|
goto error_free_subvol_name;
|
|
}
|
|
if (!root->d_inode) {
|
|
dput(root);
|
|
up_write(&s->s_umount);
|
|
deactivate_super(s);
|
|
error = -ENXIO;
|
|
goto error_free_subvol_name;
|
|
}
|
|
}
|
|
|
|
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);
|
|
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_reloc_trees(root);
|
|
WARN_ON(ret);
|
|
|
|
ret = btrfs_cleanup_fs_roots(root->fs_info);
|
|
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;
|
|
int bits = dentry->d_sb->s_blocksize_bits;
|
|
__be32 *fsid = (__be32 *)root->fs_info->fsid;
|
|
|
|
buf->f_namelen = BTRFS_NAME_LEN;
|
|
buf->f_blocks = btrfs_super_total_bytes(disk_super) >> bits;
|
|
buf->f_bfree = buf->f_blocks -
|
|
(btrfs_super_bytes_used(disk_super) >> 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 = kmalloc(sizeof(*vol), GFP_KERNEL);
|
|
if (!vol)
|
|
return -ENOMEM;
|
|
|
|
if (copy_from_user(vol, (void __user *)arg, sizeof(*vol))) {
|
|
ret = -EFAULT;
|
|
goto out;
|
|
}
|
|
|
|
switch (cmd) {
|
|
case BTRFS_IOC_SCAN_DEV:
|
|
ret = btrfs_scan_one_device(vol->name, FMODE_READ,
|
|
&btrfs_fs_type, &fs_devices);
|
|
break;
|
|
}
|
|
out:
|
|
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 struct super_operations btrfs_super_ops = {
|
|
.delete_inode = btrfs_delete_inode,
|
|
.put_super = btrfs_put_super,
|
|
.write_super = btrfs_write_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 = MISC_DYNAMIC_MINOR,
|
|
.name = "btrfs-control",
|
|
.fops = &btrfs_ctl_fops
|
|
};
|
|
|
|
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");
|