On Thu, 2012-06-21 at 17:04 -0700, Dan Williams wrote: > On Thu, Jun 21, 2012 at 4:42 PM, Praveen Murali <pmurali@xxxxxxxxxxxx> wrote: > > For my large capacity drives connected to my SAS HBA i get improper > > sector values when i use hdparm to get the native max. Also, the drives > > have known bad sectors, but when read fails, the sector information > > printed in the sense buffer is incorrect. > > In fill_result_tf() of libata-core.c the flags for the resultant tf is > > copied from the request tf before calling the qc_fill_rtf() for the > > driver. In case of SAS we convert the FIS to tf after receiving the > > response and memcpy this tf over to the result tf in > > sas_ata_qc_fill_rtf(); which results in overwriting the flags > > for rtf. As a result, when ata_tf_read_block() is called by > > ata_gen_ata_sense() ata_tf_read_block() does not find ATA_TFLAG_LBA or > > ATA_TFLAG_LBA48 in the rtf flags. Hence, the returned block value is not > > calculated correctly. > > > > The fix sets the flags in result tf from tf after calling qc_fill_rtf() > > to take care of overwrites (as in libsas). Also, if the overwrite was > > intentional, we will only setup the right bits here. > > Hmm, I think libsas is at fault here and should be using > ata_tf_from_fis() like the other ->qc_fill_rtf() implementations. libsas calls ata_tf_from_fis in sas_ata.c sas_ata_task_done() to copy the result FIS. But then it copies this information to sata_dev.tf in the domain device. It mem copies this (sata_dev.tf) over to the rtf in sas_ata_qc_fill_rtf(). Another way to fix this might be to save the flags in sata_dev.tf from qc->tf in sas_ata_task_done() before/after it calls ata_tf_from_fis(). This was it can still keep doing the mem copy and the order in libata need not be changed. What do you think? > -- > Dan Praveen -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
