Virtual storage devices

A computer implemented method of providing a virtual storage area containing no sections of data, comprising:

• providing first and second storage areas, each containing sections of data, wherein new data is written to the first storage area;
• and
• providing a plurality of pointers, wherein each pointer points to one of:
• a section of the first storage area and a section of the second storage area, wherein the virtual storage area represents a point in time copy of the first storage area and wherein, prior to writing data to a particular section of the first storage area pointed to by a particular pointer of the virtual storage area, the particular section is copied to the second storage area and the particular pointer is made to point thereto.

A computer-implemented method of accessing data stored in connection with a virtual storage area containing no sections of data, comprising:

• obtaining a pointer of the virtual storage area corresponding to the data, wherein the pointer points to a first storage area if no writes have been performed to a section of the first storage area containing the data and wherein the pointer points to a second storage area if at least one write has been performed to the section of the first storage area containing the data;
• in response to the pointer pointing to the first storage area, accessing the first storage area;
• and
• in response to the pointer pointing to the second storage area, accessing the second storage area, wherein data accessed at the second storage area is a copy of data from the first storage area that was copied in response to a first write to the section of the first storage area containing the data.

Computer software executed in a computing device that provides a virtual storage area containing no sections of data, comprising:

• executable code that provides first and second storage areas, each containing sections of data, wherein new data is written to the first storage area;
• executable code that provides a plurality of pointers, wherein each pointer points to one of:
• a section of the first storage area and a section of the second storage area, wherein the virtual storage area represents a point in time copy of the first storage;
• and
• executable code that, prior to writing data to a particular section of the first storage area pointed to by a particular pointer of the virtual storage area, executable code that copies the particular section to the second storage area and adjusts the particular pointer to point thereto.

Computer software executed in a computing device that accesses data stored in connection with a virtual storage area containing no sections of data, comprising:

• executable code that obtains a pointer of the virtual storage area corresponding to the data, wherein the pointer points to a first storage area if no writes have been performed to a section of the first storage area containing the data and wherein the pointer points to a second storage area if at least one write has been performed to the section of the first storage area containing the data;
• executable code that, in response to the pointer pointing to the first storage area, accesses the first storage area;
• and
• executable code that, in response to the pointer pointing to the second storage area, accesses the second storage area, wherein data accessed at the second storage area is a copy of data from the first storage area that was copied in response to a first write to the section of the first storage area containing the data.