From: Wang Shilong <wangsl-fnst@xxxxxxxxxxxxxx>
This patch introduces mutex lock 'quota_lock', and makes
all the user change for quota protected by quota_lock.
Signed-off-by: Wang Shilong <wangsl-fnst@xxxxxxxxxxxxxx>
Reviewed-by: Miao Xie <miaox@xxxxxxxxxxxxxx>
---
fs/btrfs/ctree.h | 3 +++
fs/btrfs/disk-io.c | 1 +
fs/btrfs/ioctl.c | 16 ++++++++++++----
3 files changed, 16 insertions(+), 4 deletions(-)
diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 6e81860..a11a8ed 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -1584,6 +1584,9 @@ struct btrfs_fs_info {
struct rb_root qgroup_tree;
spinlock_t qgroup_lock;
+ /* protect user change operations for quota */
+ struct mutex quota_lock;
+
/* list of dirty qgroups to be written at next commit */
struct list_head dirty_qgroups;
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index fe82d08..4552f14 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -2250,6 +2250,7 @@ int open_ctree(struct super_block *sb,
mutex_init(&fs_info->dev_replace.lock);
spin_lock_init(&fs_info->qgroup_lock);
+ mutex_init(&fs_info->quota_lock);
fs_info->qgroup_tree = RB_ROOT;
INIT_LIST_HEAD(&fs_info->dirty_qgroups);
fs_info->qgroup_seq = 1;
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index 222ce84..e2950f1 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -752,7 +752,7 @@ static noinline int btrfs_mksubvol(struct path *parent,
if (btrfs_root_refs(&BTRFS_I(dir)->root->root_item) == 0)
goto out_up_read;
-
+ mutex_lock(&BTRFS_I(dir)->root->fs_info->quota_lock);
if (snap_src) {
error = create_snapshot(snap_src, dir, dentry, name, namelen,
async_transid, readonly, inherit);
@@ -762,6 +762,7 @@ static noinline int btrfs_mksubvol(struct path *parent,
}
if (!error)
fsnotify_mkdir(dir, dentry);
+ mutex_unlock(&BTRFS_I(dir)->root->fs_info->quota_lock);
out_up_read:
up_read(&BTRFS_I(dir)->root->fs_info->subvol_sem);
out_dput:
@@ -3693,6 +3694,7 @@ static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
goto drop_write;
}
+ mutex_lock(&root->fs_info->quota_lock);
down_read(&root->fs_info->subvol_sem);
if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) {
trans = btrfs_start_transaction(root, 2);
@@ -3728,6 +3730,7 @@ static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)
out:
kfree(sa);
up_read(&root->fs_info->subvol_sem);
+ mutex_unlock(&root->fs_info->quota_lock);
drop_write:
mnt_drop_write_file(file);
return ret;
@@ -3754,6 +3757,7 @@ static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
goto drop_write;
}
+ mutex_lock(&root->fs_info->quota_lock);
trans = btrfs_join_transaction(root);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
@@ -3775,6 +3779,7 @@ static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)
out:
kfree(sa);
+ mutex_unlock(&root->fs_info->quota_lock);
drop_write:
mnt_drop_write_file(file);
return ret;
@@ -3805,11 +3810,11 @@ static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
ret = -EINVAL;
goto out;
}
-
+ mutex_lock(&root->fs_info->quota_lock);
trans = btrfs_join_transaction(root);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
- goto out;
+ goto out_unlock;
}
/* FIXME: check if the IDs really exist */
@@ -3824,6 +3829,8 @@ static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)
if (err && !ret)
ret = err;
+out_unlock:
+ mutex_unlock(&root->fs_info->quota_lock);
out:
kfree(sa);
drop_write:
@@ -3852,7 +3859,7 @@ static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
ret = PTR_ERR(sa);
goto drop_write;
}
-
+ mutex_lock(&root->fs_info->quota_lock);
trans = btrfs_join_transaction(root);
if (IS_ERR(trans)) {
ret = PTR_ERR(trans);
@@ -3874,6 +3881,7 @@ static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)
out:
kfree(sa);
+ mutex_unlock(&root->fs_info->quota_lock);
drop_write:
mnt_drop_write_file(file);
return ret;
--
1.7.7.6
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
