d0fc91d67c
Until now the megaraid_sas driver has reported successful completion on SYNCHRONIZE_CACHE commands without sending them down to the controller. The controller firmware has been responsible for taking care of flushing disk caches for all drives that belong to a Virtual Disk at the time of system reboot/shutdown. There may have been a reason to avoid sending SYNCHRONIZE_CACHE to a VD in the past but that no longer appears to be valid. Older versions of MegaRaid firmware (Gen2 and Gen2.5) set the WCE bit for Virtual Disks but the firmware does not report correct completion status for a SYNCHRONIZE_CACHE command. As a result, we must use another method to identify whether it is safe to send the command to the controller. We use the canHandleSyncCache firmware flag in the scratch pad register at offset 0xB4. New SYNCHRONIZE_CACHE behavior: IF 'JBOD' Driver sends SYNCHRONIZE_CACHE command to the firmware Firmware sends SYNCHRONIZE_CACHE to drive Firmware obtains status from drive and returns same status back to driver ELSEIF 'VirtualDisk' IF firmware supports new API bit called canHandleSyncCache Driver sends SYNCHRONIZE_CACHE command to the firmware Firmware does not send SYNCHRONIZE_CACHE to drives Firmware returns SUCCESS ELSE Driver does not send SYNCHRONIZE_CACHE command to the firmware Driver return SUCCESS for that command ENDIF ENDIF [mkp: edited patch description] Signed-off-by: Kashyap Desai <kashyap.desai@broadcom.com> Signed-off-by: Sumit Saxena <sumit.saxena@broadcom.com> Reviewed-by: Tomas Henzl <thenzl@redhat.com> Reviewed-by: Hannes Reinecke <hare@suse.com> Reviewed-by: Ewan D. Milne <emilne@redhat.com> Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com> |
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| .. | ||
| Kconfig.megaraid | ||
| Makefile | ||
| mbox_defs.h | ||
| mega_common.h | ||
| megaraid_ioctl.h | ||
| megaraid_mbox.c | ||
| megaraid_mbox.h | ||
| megaraid_mm.c | ||
| megaraid_mm.h | ||
| megaraid_sas_base.c | ||
| megaraid_sas_fp.c | ||
| megaraid_sas_fusion.c | ||
| megaraid_sas_fusion.h | ||
| megaraid_sas.h | ||