1 files changed, 32 insertions, 40 deletions

diff --git a/fs/bcachefs/fs-ioctl.c b/fs/bcachefs/fs-ioctl.c
index 5a39bcb597a3..3a4c24c28e7f 100644
--- a/fs/bcachefs/fs-ioctl.c
+++ b/fs/bcachefs/fs-ioctl.c
@@ -100,7 +100,8 @@ static int bch2_ioc_setflags(struct bch_fs *c,
 	}
 
 	mutex_lock(&inode->ei_update_lock);
-	ret = bch2_write_inode(c, inode, bch2_inode_flags_set, &s,
+	ret   = bch2_subvol_is_ro(c, inode->ei_subvol) ?:
+		bch2_write_inode(c, inode, bch2_inode_flags_set, &s,
 			       ATTR_CTIME);
 	mutex_unlock(&inode->ei_update_lock);
 
@@ -183,13 +184,10 @@ static int bch2_ioc_fssetxattr(struct bch_fs *c,
 	}
 
 	mutex_lock(&inode->ei_update_lock);
-	ret = bch2_set_projid(c, inode, fa.fsx_projid);
-	if (ret)
-		goto err_unlock;
-
-	ret = bch2_write_inode(c, inode, fssetxattr_inode_update_fn, &s,
+	ret   = bch2_subvol_is_ro(c, inode->ei_subvol) ?:
+		bch2_set_projid(c, inode, fa.fsx_projid) ?:
+		bch2_write_inode(c, inode, fssetxattr_inode_update_fn, &s,
 			       ATTR_CTIME);
-err_unlock:
 	mutex_unlock(&inode->ei_update_lock);
 err:
 	inode_unlock(&inode->v);
@@ -287,34 +285,26 @@ static int bch2_ioc_goingdown(struct bch_fs *c, u32 __user *arg)
 
 	bch_notice(c, "shutdown by ioctl type %u", flags);
 
-	down_write(&c->vfs_sb->s_umount);
-
 	switch (flags) {
 	case FSOP_GOING_FLAGS_DEFAULT:
-		ret = freeze_bdev(c->vfs_sb->s_bdev);
+		ret = bdev_freeze(c->vfs_sb->s_bdev);
 		if (ret)
-			goto err;
-
+			break;
 		bch2_journal_flush(&c->journal);
-		c->vfs_sb->s_flags |= SB_RDONLY;
 		bch2_fs_emergency_read_only(c);
-		thaw_bdev(c->vfs_sb->s_bdev);
+		bdev_thaw(c->vfs_sb->s_bdev);
 		break;
-
 	case FSOP_GOING_FLAGS_LOGFLUSH:
 		bch2_journal_flush(&c->journal);
 		fallthrough;
-
 	case FSOP_GOING_FLAGS_NOLOGFLUSH:
-		c->vfs_sb->s_flags |= SB_RDONLY;
 		bch2_fs_emergency_read_only(c);
 		break;
 	default:
 		ret = -EINVAL;
 		break;
 	}
-err:
-	up_write(&c->vfs_sb->s_umount);
+
 	return ret;
 }
 
@@ -347,11 +337,12 @@ static long __bch2_ioctl_subvolume_create(struct bch_fs *c, struct file *filp,
 	if (arg.flags & BCH_SUBVOL_SNAPSHOT_RO)
 		create_flags |= BCH_CREATE_SNAPSHOT_RO;
 
-	/* why do we need this lock? */
-	down_read(&c->vfs_sb->s_umount);
-
-	if (arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE)
+	if (arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE) {
+		/* sync_inodes_sb enforce s_umount is locked */
+		down_read(&c->vfs_sb->s_umount);
 		sync_inodes_sb(c->vfs_sb);
+		up_read(&c->vfs_sb->s_umount);
+	}
 retry:
 	if (arg.src_ptr) {
 		error = user_path_at(arg.dirfd,
@@ -413,7 +404,7 @@ retry:
 
 	if ((arg.flags & BCH_SUBVOL_SNAPSHOT_CREATE) &&
 	    !arg.src_ptr)
-		snapshot_src.subvol = to_bch_ei(dir)->ei_inode.bi_subvol;
+		snapshot_src.subvol = inode_inum(to_bch_ei(dir)).subvol;
 
 	inode = __bch2_create(file_mnt_idmap(filp), to_bch_ei(dir),
 			      dst_dentry, arg.mode|S_IFDIR,
@@ -435,8 +426,6 @@ err2:
 		goto retry;
 	}
 err1:
-	up_read(&c->vfs_sb->s_umount);
-
 	return error;
 }
 
@@ -453,33 +442,36 @@ static long bch2_ioctl_subvolume_create(struct bch_fs *c, struct file *filp,
 static long bch2_ioctl_subvolume_destroy(struct bch_fs *c, struct file *filp,
 				struct bch_ioctl_subvolume arg)
 {
+	const char __user *name = (void __user *)(unsigned long)arg.dst_ptr;
 	struct path path;
 	struct inode *dir;
+	struct dentry *victim;
 	int ret = 0;
 
 	if (arg.flags)
 		return -EINVAL;
 
-	ret = user_path_at(arg.dirfd,
-			(const char __user *)(unsigned long)arg.dst_ptr,
-			LOOKUP_FOLLOW, &path);
-	if (ret)
-		return ret;
+	victim = user_path_locked_at(arg.dirfd, name, &path);
+	if (IS_ERR(victim))
+		return PTR_ERR(victim);
 
-	if (path.dentry->d_sb->s_fs_info != c) {
+	if (victim->d_sb->s_fs_info != c) {
 		ret = -EXDEV;
 		goto err;
 	}
-
-	dir = path.dentry->d_parent->d_inode;
-
-	ret = __bch2_unlink(dir, path.dentry, true);
-	if (ret)
+	if (!d_is_positive(victim)) {
+		ret = -ENOENT;
 		goto err;
-
-	fsnotify_rmdir(dir, path.dentry);
-	d_delete(path.dentry);
+	}
+	dir = d_inode(path.dentry);
+	ret = __bch2_unlink(dir, victim, true);
+	if (!ret) {
+		fsnotify_rmdir(dir, victim);
+		d_delete(victim);
+	}
+	inode_unlock(dir);
 err:
+	dput(victim);
 	path_put(&path);
 	return ret;
 }