Btrfs: mount ro and remount support

This patch adds mount ro and remount support. The main
changes in patch are: adding btrfs_remount and related
helper function; splitting the transaction related code
out of close_ctree into btrfs_commit_super; updating
allocator to properly handle read only block group.

Signed-off-by: Yan Zheng <zheng.yan@oracle.com>
This commit is contained in:
Yan Zheng 2008-11-12 14:34:12 -05:00 committed by Chris Mason
parent f3465ca44e
commit c146afad2c
7 changed files with 166 additions and 61 deletions

View File

@ -541,6 +541,7 @@ struct btrfs_space_info {
u64 bytes_used;
u64 bytes_pinned;
u64 bytes_reserved;
u64 bytes_readonly;
int full;
int force_alloc;
struct list_head list;

View File

@ -1075,10 +1075,12 @@ struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
kfree(root);
return ERR_PTR(ret);
}
ret = btrfs_find_dead_roots(fs_info->tree_root,
root->root_key.objectid, root);
BUG_ON(ret);
if (!(fs_info->sb->s_flags & MS_RDONLY)) {
ret = btrfs_find_dead_roots(fs_info->tree_root,
root->root_key.objectid, root);
BUG_ON(ret);
btrfs_orphan_cleanup(root);
}
return root;
}
@ -1700,7 +1702,8 @@ struct btrfs_root *open_ctree(struct super_block *sb,
btrfs_read_block_groups(extent_root);
fs_info->generation = btrfs_super_generation(disk_super) + 1;
fs_info->generation = generation + 1;
fs_info->last_trans_committed = generation;
fs_info->data_alloc_profile = (u64)-1;
fs_info->metadata_alloc_profile = (u64)-1;
fs_info->system_alloc_profile = fs_info->metadata_alloc_profile;
@ -1715,6 +1718,9 @@ struct btrfs_root *open_ctree(struct super_block *sb,
if (!fs_info->transaction_kthread)
goto fail_cleaner;
if (sb->s_flags & MS_RDONLY)
return tree_root;
if (btrfs_super_log_root(disk_super) != 0) {
u32 blocksize;
u64 bytenr = btrfs_super_log_root(disk_super);
@ -1735,7 +1741,6 @@ struct btrfs_root *open_ctree(struct super_block *sb,
ret = btrfs_recover_log_trees(log_tree_root);
BUG_ON(ret);
}
fs_info->last_trans_committed = btrfs_super_generation(disk_super);
ret = btrfs_cleanup_reloc_trees(tree_root);
BUG_ON(ret);
@ -1955,11 +1960,56 @@ static int del_fs_roots(struct btrfs_fs_info *fs_info)
return 0;
}
int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info)
{
u64 root_objectid = 0;
struct btrfs_root *gang[8];
int i;
int ret;
while (1) {
ret = radix_tree_gang_lookup(&fs_info->fs_roots_radix,
(void **)gang, root_objectid,
ARRAY_SIZE(gang));
if (!ret)
break;
for (i = 0; i < ret; i++) {
root_objectid = gang[i]->root_key.objectid;
ret = btrfs_find_dead_roots(fs_info->tree_root,
root_objectid, gang[i]);
BUG_ON(ret);
btrfs_orphan_cleanup(gang[i]);
}
root_objectid++;
}
return 0;
}
int btrfs_commit_super(struct btrfs_root *root)
{
struct btrfs_trans_handle *trans;
int ret;
mutex_lock(&root->fs_info->cleaner_mutex);
btrfs_clean_old_snapshots(root);
mutex_unlock(&root->fs_info->cleaner_mutex);
trans = btrfs_start_transaction(root, 1);
ret = btrfs_commit_transaction(trans, root);
BUG_ON(ret);
/* run commit again to drop the original snapshot */
trans = btrfs_start_transaction(root, 1);
btrfs_commit_transaction(trans, root);
ret = btrfs_write_and_wait_transaction(NULL, root);
BUG_ON(ret);
ret = write_ctree_super(NULL, root);
return ret;
}
int close_ctree(struct btrfs_root *root)
{
int ret;
struct btrfs_trans_handle *trans;
struct btrfs_fs_info *fs_info = root->fs_info;
int ret;
fs_info->closing = 1;
smp_mb();
@ -1967,16 +2017,12 @@ int close_ctree(struct btrfs_root *root)
kthread_stop(root->fs_info->transaction_kthread);
kthread_stop(root->fs_info->cleaner_kthread);
btrfs_clean_old_snapshots(root);
trans = btrfs_start_transaction(root, 1);
ret = btrfs_commit_transaction(trans, root);
/* run commit again to drop the original snapshot */
trans = btrfs_start_transaction(root, 1);
btrfs_commit_transaction(trans, root);
ret = btrfs_write_and_wait_transaction(NULL, root);
BUG_ON(ret);
write_ctree_super(NULL, root);
if (!(fs_info->sb->s_flags & MS_RDONLY)) {
ret = btrfs_commit_super(root);
if (ret) {
printk("btrfs: commit super returns %d\n", ret);
}
}
if (fs_info->delalloc_bytes) {
printk("btrfs: at unmount delalloc count %Lu\n",
@ -2000,12 +2046,10 @@ int close_ctree(struct btrfs_root *root)
free_extent_buffer(root->fs_info->dev_root->node);
btrfs_free_block_groups(root->fs_info);
fs_info->closing = 2;
del_fs_roots(fs_info);
filemap_write_and_wait(fs_info->btree_inode->i_mapping);
truncate_inode_pages(fs_info->btree_inode->i_mapping, 0);
iput(fs_info->btree_inode);
btrfs_stop_workers(&fs_info->fixup_workers);
btrfs_stop_workers(&fs_info->delalloc_workers);
@ -2014,7 +2058,6 @@ int close_ctree(struct btrfs_root *root)
btrfs_stop_workers(&fs_info->endio_write_workers);
btrfs_stop_workers(&fs_info->submit_workers);
iput(fs_info->btree_inode);
#if 0
while(!list_empty(&fs_info->hashers)) {
struct btrfs_hasher *hasher;

View File

@ -38,6 +38,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
int close_ctree(struct btrfs_root *root);
int write_ctree_super(struct btrfs_trans_handle *trans,
struct btrfs_root *root);
int btrfs_commit_super(struct btrfs_root *root);
struct extent_buffer *btrfs_find_tree_block(struct btrfs_root *root,
u64 bytenr, u32 blocksize);
struct btrfs_root *btrfs_lookup_fs_root(struct btrfs_fs_info *fs_info,
@ -49,6 +50,7 @@ struct btrfs_root *btrfs_read_fs_root_no_radix(struct btrfs_root *tree_root,
struct btrfs_key *location);
struct btrfs_root *btrfs_read_fs_root_no_name(struct btrfs_fs_info *fs_info,
struct btrfs_key *location);
int btrfs_cleanup_fs_roots(struct btrfs_fs_info *fs_info);
int btrfs_insert_dev_radix(struct btrfs_root *root,
struct block_device *bdev,
u64 device_id,

View File

@ -1794,7 +1794,7 @@ static int update_space_info(struct btrfs_fs_info *info, u64 flags,
*space_info = found;
return 0;
}
found = kmalloc(sizeof(*found), GFP_NOFS);
found = kzalloc(sizeof(*found), GFP_NOFS);
if (!found)
return -ENOMEM;
@ -1807,6 +1807,7 @@ static int update_space_info(struct btrfs_fs_info *info, u64 flags,
found->bytes_used = bytes_used;
found->bytes_pinned = 0;
found->bytes_reserved = 0;
found->bytes_readonly = 0;
found->full = 0;
found->force_alloc = 0;
*space_info = found;
@ -1829,6 +1830,19 @@ static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
}
}
static void set_block_group_readonly(struct btrfs_block_group_cache *cache)
{
spin_lock(&cache->space_info->lock);
spin_lock(&cache->lock);
if (!cache->ro) {
cache->space_info->bytes_readonly += cache->key.offset -
btrfs_block_group_used(&cache->item);
cache->ro = 1;
}
spin_unlock(&cache->lock);
spin_unlock(&cache->space_info->lock);
}
static u64 reduce_alloc_profile(struct btrfs_root *root, u64 flags)
{
u64 num_devices = root->fs_info->fs_devices->num_devices;
@ -1865,7 +1879,9 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
u64 thresh;
u64 start;
u64 num_bytes;
int ret = 0, waited = 0;
int ret = 0;
mutex_lock(&extent_root->fs_info->chunk_mutex);
flags = reduce_alloc_profile(extent_root, flags);
@ -1887,46 +1903,28 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
goto out;
}
thresh = div_factor(space_info->total_bytes, 6);
thresh = space_info->total_bytes - space_info->bytes_readonly;
thresh = div_factor(thresh, 6);
if (!force &&
(space_info->bytes_used + space_info->bytes_pinned +
space_info->bytes_reserved + alloc_bytes) < thresh) {
spin_unlock(&space_info->lock);
goto out;
}
spin_unlock(&space_info->lock);
ret = mutex_trylock(&extent_root->fs_info->chunk_mutex);
if (!ret && !force) {
goto out;
} else if (!ret) {
mutex_lock(&extent_root->fs_info->chunk_mutex);
waited = 1;
}
if (waited) {
spin_lock(&space_info->lock);
if (space_info->full) {
spin_unlock(&space_info->lock);
goto out_unlock;
}
spin_unlock(&space_info->lock);
}
ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
if (ret) {
printk("space info full %Lu\n", flags);
space_info->full = 1;
goto out_unlock;
goto out;
}
ret = btrfs_make_block_group(trans, extent_root, 0, flags,
BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
BUG_ON(ret);
out_unlock:
mutex_unlock(&extent_root->fs_info->chunk_mutex);
out:
mutex_unlock(&extent_root->fs_info->chunk_mutex);
return ret;
}
@ -1956,12 +1954,18 @@ static int update_block_group(struct btrfs_trans_handle *trans,
if (alloc) {
old_val += num_bytes;
cache->space_info->bytes_used += num_bytes;
if (cache->ro) {
cache->space_info->bytes_readonly -= num_bytes;
WARN_ON(1);
}
btrfs_set_block_group_used(&cache->item, old_val);
spin_unlock(&cache->lock);
spin_unlock(&cache->space_info->lock);
} else {
old_val -= num_bytes;
cache->space_info->bytes_used -= num_bytes;
if (cache->ro)
cache->space_info->bytes_readonly += num_bytes;
btrfs_set_block_group_used(&cache->item, old_val);
spin_unlock(&cache->lock);
spin_unlock(&cache->space_info->lock);
@ -5560,8 +5564,7 @@ int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start)
BUG_ON(IS_ERR(reloc_inode));
__alloc_chunk_for_shrink(root, block_group, 1);
block_group->ro = 1;
block_group->space_info->total_bytes -= block_group->key.offset;
set_block_group_readonly(block_group);
btrfs_start_delalloc_inodes(info->tree_root);
btrfs_wait_ordered_extents(info->tree_root, 0);
@ -5868,6 +5871,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
block_group = btrfs_lookup_block_group(root->fs_info, group_start);
BUG_ON(!block_group);
BUG_ON(!block_group->ro);
memcpy(&key, &block_group->key, sizeof(key));
@ -5881,6 +5885,11 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
list_del(&block_group->list);
up_write(&block_group->space_info->groups_sem);
spin_lock(&block_group->space_info->lock);
block_group->space_info->total_bytes -= block_group->key.offset;
block_group->space_info->bytes_readonly -= block_group->key.offset;
spin_unlock(&block_group->space_info->lock);
/*
memset(shrink_block_group, 0, sizeof(*shrink_block_group));
kfree(shrink_block_group);

View File

@ -1808,10 +1808,6 @@ void btrfs_orphan_cleanup(struct btrfs_root *root)
struct inode *inode;
int ret = 0, nr_unlink = 0, nr_truncate = 0;
/* don't do orphan cleanup if the fs is readonly. */
if (root->fs_info->sb->s_flags & MS_RDONLY)
return;
path = btrfs_alloc_path();
if (!path)
return;
@ -3050,7 +3046,7 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
struct btrfs_root *root = bi->root;
struct btrfs_root *sub_root = root;
struct btrfs_key location;
int ret, new, do_orphan = 0;
int ret, new;
if (dentry->d_name.len > BTRFS_NAME_LEN)
return ERR_PTR(-ENAMETOOLONG);
@ -3076,13 +3072,9 @@ static struct dentry *btrfs_lookup(struct inode *dir, struct dentry *dentry,
if (new && root != sub_root) {
igrab(inode);
sub_root->inode = inode;
do_orphan = 1;
}
}
if (unlikely(do_orphan))
btrfs_orphan_cleanup(sub_root);
return d_splice_alias(inode, dentry);
}
@ -3237,7 +3229,7 @@ int btrfs_write_inode(struct inode *inode, int wait)
struct btrfs_trans_handle *trans;
int ret = 0;
if (root->fs_info->closing > 1)
if (root->fs_info->btree_inode == inode)
return 0;
if (wait) {
@ -4625,6 +4617,9 @@ int btrfs_start_delalloc_inodes(struct btrfs_root *root)
struct inode *inode;
unsigned long flags;
if (root->fs_info->sb->s_flags & MS_RDONLY)
return -EROFS;
spin_lock_irqsave(&root->fs_info->delalloc_lock, flags);
while(!list_empty(head)) {
binode = list_entry(head->next, struct btrfs_inode,

View File

@ -378,6 +378,9 @@ static int btrfs_ioctl_resize(struct btrfs_root *root, void __user *arg)
int namelen;
int mod = 0;
if (root->fs_info->sb->s_flags & MS_RDONLY)
return -EROFS;
vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
if (!vol_args)
@ -478,6 +481,9 @@ static noinline int btrfs_ioctl_snap_create(struct file *file,
int namelen;
int ret;
if (root->fs_info->sb->s_flags & MS_RDONLY)
return -EROFS;
vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
if (!vol_args)
@ -534,6 +540,11 @@ static int btrfs_ioctl_defrag(struct file *file)
{
struct inode *inode = fdentry(file)->d_inode;
struct btrfs_root *root = BTRFS_I(inode)->root;
int ret;
ret = mnt_want_write(file->f_path.mnt);
if (ret)
return ret;
switch (inode->i_mode & S_IFMT) {
case S_IFDIR:
@ -575,6 +586,9 @@ long btrfs_ioctl_rm_dev(struct btrfs_root *root, void __user *arg)
struct btrfs_ioctl_vol_args *vol_args;
int ret;
if (root->fs_info->sb->s_flags & MS_RDONLY)
return -EROFS;
vol_args = kmalloc(sizeof(*vol_args), GFP_NOFS);
if (!vol_args)
@ -621,6 +635,10 @@ long btrfs_ioctl_clone(struct file *file, unsigned long srcfd, u64 off,
* they don't overlap)?
*/
ret = mnt_want_write(file->f_path.mnt);
if (ret)
return ret;
src_file = fget(srcfd);
if (!src_file)
return -EBADF;
@ -958,6 +976,10 @@ long btrfs_ioctl_trans_start(struct file *file)
goto out;
}
ret = mnt_want_write(file->f_path.mnt);
if (ret)
goto out;
mutex_lock(&root->fs_info->trans_mutex);
root->fs_info->open_ioctl_trans++;
mutex_unlock(&root->fs_info->trans_mutex);

View File

@ -370,6 +370,9 @@ int btrfs_sync_fs(struct super_block *sb, int wait)
int ret;
root = btrfs_sb(sb);
if (sb->s_flags & MS_RDONLY)
return 0;
sb->s_dirt = 0;
if (!wait) {
filemap_flush(root->fs_info->btree_inode->i_mapping);
@ -438,7 +441,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
up_write(&s->s_umount);
deactivate_super(s);
error = -EBUSY;
goto error_bdev;
goto error_close_devices;
}
} else {
@ -487,7 +490,7 @@ static int btrfs_get_sb(struct file_system_type *fs_type, int flags,
error_s:
error = PTR_ERR(s);
error_bdev:
error_close_devices:
btrfs_close_devices(fs_devices);
error_free_subvol_name:
kfree(subvol_name);
@ -495,6 +498,35 @@ error:
return error;
}
static int btrfs_remount(struct super_block *sb, int *flags, char *data)
{
struct btrfs_root *root = btrfs_sb(sb);
int ret;
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 (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);
@ -582,6 +614,7 @@ static struct super_operations btrfs_super_ops = {
.alloc_inode = btrfs_alloc_inode,
.destroy_inode = btrfs_destroy_inode,
.statfs = btrfs_statfs,
.remount_fs = btrfs_remount,
.write_super_lockfs = btrfs_write_super_lockfs,
.unlockfs = btrfs_unlockfs,
};