This one was noticed by Gilbert Wu of Adaptec: The libata core actually does the DMA mapping for you, so there has to be an exception in the device drivers that *don't* do dma mapping for ATA commands. However, since we've already done this, libsas must now dma map any ATA commands that it wishes to issue ... and yes, this is a horrible mess. Additionally, the test in aic94xx for ATA protocols isn't quite right. --- James Index: BUILD-2.6/drivers/scsi/libsas/sas_discover.c =================================================================== --- BUILD-2.6.orig/drivers/scsi/libsas/sas_discover.c 2007-07-16 13:01:19.000000000 -0500 +++ BUILD-2.6/drivers/scsi/libsas/sas_discover.c 2007-07-16 13:39:57.000000000 -0500 @@ -110,6 +110,13 @@ static int sas_execute_task(struct sas_t task->total_xfer_len = size; task->data_dir = pci_dma_dir; task->task_done = sas_disc_task_done; + if (pci_dma_dir != PCI_DMA_NONE && + sas_protocol_ata(task->task_proto)) { + task->num_scatter = pci_map_sg(task->dev->port->ha->pcidev, + task->scatter, + task->num_scatter, + task->data_dir); + } for (retries = 0; retries < 5; retries++) { task->task_state_flags = SAS_TASK_STATE_PENDING; @@ -192,8 +199,13 @@ static int sas_execute_task(struct sas_t } } ex_err: - if (pci_dma_dir != PCI_DMA_NONE) + if (pci_dma_dir != PCI_DMA_NONE) { + if (sas_protocol_ata(task->task_proto)) + pci_unmap_sg(task->dev->port->ha->pcidev, + task->scatter, task->num_scatter, + task->data_dir); kfree(scatter); + } out: return res; } Index: BUILD-2.6/drivers/scsi/aic94xx/aic94xx_task.c =================================================================== --- BUILD-2.6.orig/drivers/scsi/aic94xx/aic94xx_task.c 2007-07-16 13:37:59.000000000 -0500 +++ BUILD-2.6/drivers/scsi/aic94xx/aic94xx_task.c 2007-07-16 13:38:46.000000000 -0500 @@ -76,7 +76,7 @@ static inline int asd_map_scatterlist(st /* STP tasks come from libata which has already mapped * the SG list */ - if (task->task_proto == SAS_PROTOCOL_STP) + if (sas_protocol_ata(task->task_proto)) num_sg = task->num_scatter; else num_sg = pci_map_sg(asd_ha->pcidev, task->scatter, @@ -125,7 +125,7 @@ static inline int asd_map_scatterlist(st return 0; err_unmap: - if (task->task_proto != SAS_PROTOCOL_STP) + if (sas_protocol_ata(task->task_proto)) pci_unmap_sg(asd_ha->pcidev, task->scatter, task->num_scatter, task->data_dir); return res; Index: BUILD-2.6/include/scsi/scsi_transport_sas.h =================================================================== --- BUILD-2.6.orig/include/scsi/scsi_transport_sas.h 2007-07-16 13:34:05.000000000 -0500 +++ BUILD-2.6/include/scsi/scsi_transport_sas.h 2007-07-16 13:35:58.000000000 -0500 @@ -23,6 +23,12 @@ enum sas_protocol { SAS_PROTOCOL_SSP = 0x08, }; +static inline int sas_protocol_ata(enum sas_protocol proto) +{ + return ((proto & SAS_PROTOCOL_SATA) || + (proto & SAS_PROTOCOL_STP))? 1 : 0; +} + enum sas_linkrate { /* These Values are defined in the SAS standard */ SAS_LINK_RATE_UNKNOWN = 0, - 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