Fujitsu MHV2040BH Product Manual page 249

(3) Invalidating caching-target data
Data that is a target of caching on the data buffer is invalidated under the
following conditions:
1)-1 Any command other than the following commands is issued. (All caching-
target data is invalidated.)
READ BUFFER
WRITE BUFFER
RECALIBRATE
FORMAT TRACK
SET FEATURES
SECURITY ERASE UNIT
DEVICE CONFIGURATION
DOWNLOAD MICROCODE
UNSUPPORT COMMAND (INVALID COMMAND)
1)-2 Commands that partially invalidate caching data
READ DMA/READ MULTIPLE/READ SECTOR(S)
READ DMA EXT/READ MULTIPLE EXT/READ SECTOR(S) EXT
READ FP DMA QUEUED
WRITE DMA/WRITE MULTIPLE/WRITE SECTOR(S)
WRITE DMA EXT/WRITE MULTIPLE EXT/WRITE SECTOR(S) EXT
WRITE DMA FUA EXT/WRITE MULTIPLE FUA EXT
WRITE FP DMA QUEUED
SMART
2) A COMRESET is issued or the power is turned off.
3) When HOST CRC ERROR has occurred.
C141-E224
6.4 Read-ahead Cache
6-15