18c2ecf20Sopenharmony_ci.. SPDX-License-Identifier: GPL-2.0 28c2ecf20Sopenharmony_ci 38c2ecf20Sopenharmony_ci====================================== 48c2ecf20Sopenharmony_ciLinux SCSI Disk Driver (sd) Parameters 58c2ecf20Sopenharmony_ci====================================== 68c2ecf20Sopenharmony_ci 78c2ecf20Sopenharmony_cicache_type (RW) 88c2ecf20Sopenharmony_ci--------------- 98c2ecf20Sopenharmony_ciEnable/disable drive write & read cache. 108c2ecf20Sopenharmony_ci 118c2ecf20Sopenharmony_ci=========================== === === =========== ========== 128c2ecf20Sopenharmony_ci cache_type string WCE RCD Write cache Read cache 138c2ecf20Sopenharmony_ci=========================== === === =========== ========== 148c2ecf20Sopenharmony_ci write through 0 0 off on 158c2ecf20Sopenharmony_ci none 0 1 off off 168c2ecf20Sopenharmony_ci write back 1 0 on on 178c2ecf20Sopenharmony_ci write back, no read (daft) 1 1 on off 188c2ecf20Sopenharmony_ci=========================== === === =========== ========== 198c2ecf20Sopenharmony_ci 208c2ecf20Sopenharmony_ciTo set cache type to "write back" and save this setting to the drive:: 218c2ecf20Sopenharmony_ci 228c2ecf20Sopenharmony_ci # echo "write back" > cache_type 238c2ecf20Sopenharmony_ci 248c2ecf20Sopenharmony_ciTo modify the caching mode without making the change persistent, prepend 258c2ecf20Sopenharmony_ci"temporary " to the cache type string. E.g.:: 268c2ecf20Sopenharmony_ci 278c2ecf20Sopenharmony_ci # echo "temporary write back" > cache_type 28