1. A system comprising: storage media; and control logic coupled to the storage media, wherein the control logic is configured to: receive a write request specifying a write to a logical address; determine whether the write request specifies writing a predetermined pattern; in response to determining that the write request specifies writing the predetermined pattern, change an indicator from a first value to a second value, the indicator having the first value indicating that a physical location on the storage media corresponding to the logical address contains valid data, and the indicator having the second value indicating that the physical location corresponding to the logical address contains invalid data, the changed indicator being part of a first data structure mapping physical locations on the storage media to respective indicators for indicating whether the corresponding physical locations contain valid or invalid data.