Commit 905b0dda authored by Miao Xie's avatar Miao Xie Committed by Chris Mason
Browse files

Btrfs: get write access for qgroup operations 



We need get write access for qgroup operations, or we will modify the R/O fs.

Signed-off-by: default avatarMiao Xie <miaox@cn.fujitsu.com>
Signed-off-by: default avatarChris Mason <chris.mason@fusionio.com>
parent b8e95489

fs/btrfs/ioctl.c

+48 −25
Original line number Diff line number Diff line
@@ -3558,8 +3558,9 @@ static long btrfs_ioctl_balance_progress(struct btrfs_root *root, 
	return ret;

}



static long btrfs_ioctl_quota_ctl(struct btrfs_root *root, void __user *arg)

static long btrfs_ioctl_quota_ctl(struct file *file, void __user *arg)

{

	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;

	struct btrfs_ioctl_quota_ctl_args *sa;

	struct btrfs_trans_handle *trans = NULL;

	int ret;
@@ -3568,12 +3569,15 @@ static long btrfs_ioctl_quota_ctl(struct btrfs_root *root, void __user *arg) 
	if (!capable(CAP_SYS_ADMIN))

		return -EPERM;



	if (root->fs_info->sb->s_flags & MS_RDONLY)

		return -EROFS;

	ret = mnt_want_write_file(file);

	if (ret)

		return ret;



	sa = memdup_user(arg, sizeof(*sa));

	if (IS_ERR(sa))

		return PTR_ERR(sa);

	if (IS_ERR(sa)) {

		ret = PTR_ERR(sa);

		goto drop_write;

	}



	if (sa->cmd != BTRFS_QUOTA_CTL_RESCAN) {

		trans = btrfs_start_transaction(root, 2);
@@ -3606,14 +3610,16 @@ static long btrfs_ioctl_quota_ctl(struct btrfs_root *root, void __user *arg) 
		if (err && !ret)

			ret = err;

	}



out:

	kfree(sa);

drop_write:

	mnt_drop_write_file(file);

	return ret;

}



static long btrfs_ioctl_qgroup_assign(struct btrfs_root *root, void __user *arg)

static long btrfs_ioctl_qgroup_assign(struct file *file, void __user *arg)

{

	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;

	struct btrfs_ioctl_qgroup_assign_args *sa;

	struct btrfs_trans_handle *trans;

	int ret;
@@ -3622,12 +3628,15 @@ static long btrfs_ioctl_qgroup_assign(struct btrfs_root *root, void __user *arg) 
	if (!capable(CAP_SYS_ADMIN))

		return -EPERM;



	if (root->fs_info->sb->s_flags & MS_RDONLY)

		return -EROFS;

	ret = mnt_want_write_file(file);

	if (ret)

		return ret;



	sa = memdup_user(arg, sizeof(*sa));

	if (IS_ERR(sa))

		return PTR_ERR(sa);

	if (IS_ERR(sa)) {

		ret = PTR_ERR(sa);

		goto drop_write;

	}



	trans = btrfs_join_transaction(root);

	if (IS_ERR(trans)) {
@@ -3650,11 +3659,14 @@ static long btrfs_ioctl_qgroup_assign(struct btrfs_root *root, void __user *arg) 


out:

	kfree(sa);

drop_write:

	mnt_drop_write_file(file);

	return ret;

}



static long btrfs_ioctl_qgroup_create(struct btrfs_root *root, void __user *arg)

static long btrfs_ioctl_qgroup_create(struct file *file, void __user *arg)

{

	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;

	struct btrfs_ioctl_qgroup_create_args *sa;

	struct btrfs_trans_handle *trans;

	int ret;
@@ -3663,12 +3675,15 @@ static long btrfs_ioctl_qgroup_create(struct btrfs_root *root, void __user *arg) 
	if (!capable(CAP_SYS_ADMIN))

		return -EPERM;



	if (root->fs_info->sb->s_flags & MS_RDONLY)

		return -EROFS;

	ret = mnt_want_write_file(file);

	if (ret)

		return ret;



	sa = memdup_user(arg, sizeof(*sa));

	if (IS_ERR(sa))

		return PTR_ERR(sa);

	if (IS_ERR(sa)) {

		ret = PTR_ERR(sa);

		goto drop_write;

	}



	trans = btrfs_join_transaction(root);

	if (IS_ERR(trans)) {
@@ -3690,11 +3705,14 @@ static long btrfs_ioctl_qgroup_create(struct btrfs_root *root, void __user *arg) 


out:

	kfree(sa);

drop_write:

	mnt_drop_write_file(file);

	return ret;

}



static long btrfs_ioctl_qgroup_limit(struct btrfs_root *root, void __user *arg)

static long btrfs_ioctl_qgroup_limit(struct file *file, void __user *arg)

{

	struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root;

	struct btrfs_ioctl_qgroup_limit_args *sa;

	struct btrfs_trans_handle *trans;

	int ret;
@@ -3704,12 +3722,15 @@ static long btrfs_ioctl_qgroup_limit(struct btrfs_root *root, void __user *arg) 
	if (!capable(CAP_SYS_ADMIN))

		return -EPERM;



	if (root->fs_info->sb->s_flags & MS_RDONLY)

		return -EROFS;

	ret = mnt_want_write_file(file);

	if (ret)

		return ret;



	sa = memdup_user(arg, sizeof(*sa));

	if (IS_ERR(sa))

		return PTR_ERR(sa);

	if (IS_ERR(sa)) {

		ret = PTR_ERR(sa);

		goto drop_write;

	}



	trans = btrfs_join_transaction(root);

	if (IS_ERR(trans)) {
@@ -3732,6 +3753,8 @@ static long btrfs_ioctl_qgroup_limit(struct btrfs_root *root, void __user *arg) 


out:

	kfree(sa);

drop_write:

	mnt_drop_write_file(file);

	return ret;

}
@@ -3907,13 +3930,13 @@ long btrfs_ioctl(struct file *file, unsigned int 
	case BTRFS_IOC_GET_DEV_STATS:

		return btrfs_ioctl_get_dev_stats(root, argp);

	case BTRFS_IOC_QUOTA_CTL:

		return btrfs_ioctl_quota_ctl(root, argp);

		return btrfs_ioctl_quota_ctl(file, argp);

	case BTRFS_IOC_QGROUP_ASSIGN:

		return btrfs_ioctl_qgroup_assign(root, argp);

		return btrfs_ioctl_qgroup_assign(file, argp);

	case BTRFS_IOC_QGROUP_CREATE:

		return btrfs_ioctl_qgroup_create(root, argp);

		return btrfs_ioctl_qgroup_create(file, argp);

	case BTRFS_IOC_QGROUP_LIMIT:

		return btrfs_ioctl_qgroup_limit(root, argp);

		return btrfs_ioctl_qgroup_limit(file, argp);

	case BTRFS_IOC_DEV_REPLACE:

		return btrfs_ioctl_dev_replace(root, argp);

	}