162306a36Sopenharmony_ci.. SPDX-License-Identifier: GPL-2.0 262306a36Sopenharmony_ci 362306a36Sopenharmony_ci====================================== 462306a36Sopenharmony_ciLinux SCSI Disk Driver (sd) Parameters 562306a36Sopenharmony_ci====================================== 662306a36Sopenharmony_ci 762306a36Sopenharmony_cicache_type (RW) 862306a36Sopenharmony_ci--------------- 962306a36Sopenharmony_ciEnable/disable drive write & read cache. 1062306a36Sopenharmony_ci 1162306a36Sopenharmony_ci=========================== === === =========== ========== 1262306a36Sopenharmony_ci cache_type string WCE RCD Write cache Read cache 1362306a36Sopenharmony_ci=========================== === === =========== ========== 1462306a36Sopenharmony_ci write through 0 0 off on 1562306a36Sopenharmony_ci none 0 1 off off 1662306a36Sopenharmony_ci write back 1 0 on on 1762306a36Sopenharmony_ci write back, no read (daft) 1 1 on off 1862306a36Sopenharmony_ci=========================== === === =========== ========== 1962306a36Sopenharmony_ci 2062306a36Sopenharmony_ciTo set cache type to "write back" and save this setting to the drive:: 2162306a36Sopenharmony_ci 2262306a36Sopenharmony_ci # echo "write back" > cache_type 2362306a36Sopenharmony_ci 2462306a36Sopenharmony_ciTo modify the caching mode without making the change persistent, prepend 2562306a36Sopenharmony_ci"temporary " to the cache type string. E.g.:: 2662306a36Sopenharmony_ci 2762306a36Sopenharmony_ci # echo "temporary write back" > cache_type 28