Locking a cache line for write operations on a bus

A method, comprising:

• allocating a cache line in a cache for a target address;
• setting a lock for the cache line;
• writing data to the cache line while the lock for the cache line is set;
• processing an interrupt while filling the cache line, wherein the lock prevents the data in the cache line from being cast out while the interrupt is being processed;
• returning to the filling the cache line after completing the processing the interrupt;
• and
• flushing all the data in the cache line to the target address over a bus in response to completing the writing to the cache line.

A system in communication with an external device over a bus, comprising:

• a processor;
• a cache;
• a computer readable storage medium having instructions executed by the processor to perform operations, the operations comprising:
• allocating a cache line in the cache for a target address at the external device;
• setting a lock for the cache line;
• writing data to the cache line while the lock for the cache line is set;
• processing an interrupt while filling the cache line, wherein the lock prevents the data in the cache line from being cast out while the interrupt is being processed;
• returning to the filling the cache line after completing the processing the interrupt;
• and
• flushing all the data in the cache line to the target address over the bus to the external device in response to completing the writing to the cache line.