Data reliabilty bit storage qualifier and logical unit metadata

Abstract

The present invention includes embodiments that minimize storage space and storage time in storage systems. In particular, the present invention appends additional information to data that will be stored. The contents of the additional information indicate the status of the stored data. Preferably, the additional information is not combined with another type of information so that it directly indicates the status of the stored data. Alternatively, the additional information can be used to determine the status of one or more corresponding data that are not the data to which the additional information is appended.

1 . A method for storing data comprising the step of storing first information with first data, wherein the first information directly indicates the status of the first data.  
     
     
         2 . The method of  claim 1  wherein the status indicates a reliability of the first data.  
     
     
         3 . The method of  claim 1  wherein the first information is a data reliability qualifier bit.  
     
     
         4 . The method of  claim 3  wherein the first information is embedded with the first data.  
     
     
         5 . The method of  claim 1  wherein the first information is appended with the first data.  
     
     
         6 . The method of  claim 1  further comprising the step of storing second information with second data, the second information indicating the status of the first data.  
     
     
         7 . The method of  claim 6  wherein the second information is set to indicate that the first data is unreliable.  
     
     
         8 . A method for protecting data comprising the step of accompanying first information with first data, wherein the first information indicates status of second data associated with the first data.  
     
     
         9 . The method of  claim 8  wherein the status indicates a reliability of the second data.  
     
     
         10 . The method of  claim 1  wherein the first information is a data reliability qualifier.  
     
     
         11 . The method of  claim 10  wherein the first data is parity data.  
     
     
         12 . The method of  claim 8  wherein the first information is set to indicate that the second data is unreliable.  
     
     
         13 . The method of  claim 8  further comprising the step of storing second information to the second data, the second information indicating the status of the second data.  
     
     
         14 . The method of  claim 13  wherein the second information is set to indicate that the second data is unreliable.  
     
     
         15 . An apparatus comprising: 
 storage areas; and    circuitry configured to perform at least one of a group consisting of a reading and a writing of the storage areas, wherein at least one of the storage areas includes first information accompanying first data, wherein the first information indicates status of second data associated with the first data.    
     
     
         16 . The apparatus of  claim 15  wherein the circuitry includes a controller that is adapted to store the first information with the first data.  
     
     
         17 . The apparatus of  claim 15  wherein at least another of the storage areas includes second information stored with the second data that indicates a status of the second data.  
     
     
         18 . The apparatus of  claim 17  wherein the storage areas are in a RAID configuration.  
     
     
         19 . The apparatus of  claim 15  wherein the first information is appended to the first data.  
     
     
         20 . The apparatus of  claim 15  wherein the first information is embedded in the first data.  
     
     
         21 . The apparatus of  claim 15  wherein the first information and the first data are generated by the same function.