限制IAM用户

Question

我在当前存储桶上获得了IAM策略，该存储桶将列出所有存储桶并允许完全访问S3帐户内的指定存储桶。问题是，我现在要限制上传到指定存储桶内的特定文件夹。有没有办法做到这一点，并指定只能上传到顶级文件夹，而不是列出政策中的特定文件夹？这就是我目前所拥有的：

{
"Statement": [
{
  "Effect": "Allow",
  "Action": [
    "s3:ListBucket",
    "s3:GetBucketLocation",
    "s3:ListBucketMultipartUploads"
  ],
  "Resource": "arn:aws:s3:::MYBUCKETNAME",
  "Condition": {}
},
{
  "Effect": "Allow",
  "Action": [
    "s3:AbortMultipartUpload",
    "s3:DeleteObject",
    "s3:DeleteObjectVersion",
    "s3:GetObject",
    "s3:GetObjectAcl",
    "s3:GetObjectVersion",
    "s3:GetObjectVersionAcl",
    "s3:PutObject",
    "s3:PutObjectAcl",
    "s3:PutObjectAclVersion"
  ],
  "Resource": "arn:aws:s3:::MYBUCKETNAME/*",
  "Condition": {}
},
{
  "Effect": "Allow",
  "Action": "s3:ListAllMyBuckets",
  "Resource": "*",
  "Condition": {}
}
 ]
}