diff options
| author | Tejun Heo <htejun@gmail.com> | 2007-12-05 16:43:11 +0900 |
|---|---|---|
| committer | Jeff Garzik <jeff@garzik.org> | 2008-01-23 05:24:14 -0500 |
| commit | ff2aeb1eb64c8a4770a6304f9addbae9f9828646 (patch) | |
| tree | c6febbec290ec6c40bf3abc7bcdb7188f5039443 /drivers/scsi | |
| parent | f92a26365a72333f418abe82700c6030d4a1a807 (diff) | |
libata: convert to chained sg
libata used private sg iterator to handle padding sg. Now that sg can
be chained, padding can be handled using standard sg ops. Convert to
chained sg.
* s/qc->__sg/qc->sg/
* s/qc->pad_sgent/qc->extra_sg[]/. Because chaining consumes one sg
entry. There need to be two extra sg entries. The renaming is also
for future addition of other extra sg entries.
* Padding setup is moved into ata_sg_setup_extra() which is organized
in a way that future addition of other extra sg entries is easy.
* qc->orig_n_elem is unused and removed.
* qc->n_elem now contains the number of sg entries that LLDs should
map. qc->mapped_n_elem is added to carry the original number of
mapped sgs for unmapping.
* The last sg of the original sg list is used to chain to extra sg
list. The original last sg is pointed to by qc->last_sg and the
content is stored in qc->saved_last_sg. It's restored during
ata_sg_clean().
* All sg walking code has been updated. Unnecessary assertions and
checks for conditions the core layer already guarantees are removed.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Jeff Garzik <jeff@garzik.org>
Diffstat (limited to 'drivers/scsi')
| -rw-r--r-- | drivers/scsi/ipr.c | 3 | ||||
| -rw-r--r-- | drivers/scsi/libsas/sas_ata.c | 10 |
2 files changed, 6 insertions, 7 deletions
diff --git a/drivers/scsi/ipr.c b/drivers/scsi/ipr.c index 3e78bc2d917..aa0df0a4b22 100644 --- a/drivers/scsi/ipr.c +++ b/drivers/scsi/ipr.c @@ -5142,6 +5142,7 @@ static void ipr_build_ata_ioadl(struct ipr_cmnd *ipr_cmd, struct ipr_ioadl_desc *last_ioadl = NULL; int len = qc->nbytes + qc->pad_len; struct scatterlist *sg; + unsigned int si; if (len == 0) return; @@ -5159,7 +5160,7 @@ static void ipr_build_ata_ioadl(struct ipr_cmnd *ipr_cmd, cpu_to_be32(sizeof(struct ipr_ioadl_desc) * ipr_cmd->dma_use_sg); } - ata_for_each_sg(sg, qc) { + for_each_sg(qc->sg, sg, qc->n_elem, si) { ioadl->flags_and_data_len = cpu_to_be32(ioadl_flags | sg_dma_len(sg)); ioadl->address = cpu_to_be32(sg_dma_address(sg)); diff --git a/drivers/scsi/libsas/sas_ata.c b/drivers/scsi/libsas/sas_ata.c index f78d0605747..827cfb132f2 100644 --- a/drivers/scsi/libsas/sas_ata.c +++ b/drivers/scsi/libsas/sas_ata.c @@ -158,8 +158,8 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc) struct Scsi_Host *host = sas_ha->core.shost; struct sas_internal *i = to_sas_internal(host->transportt); struct scatterlist *sg; - unsigned int num = 0; unsigned int xfer = 0; + unsigned int si; task = sas_alloc_task(GFP_ATOMIC); if (!task) @@ -181,17 +181,15 @@ static unsigned int sas_ata_qc_issue(struct ata_queued_cmd *qc) task->total_xfer_len = qc->nbytes + qc->pad_len; task->num_scatter = qc->pad_len ? qc->n_elem + 1 : qc->n_elem; } else { - ata_for_each_sg(sg, qc) { - num++; + for_each_sg(qc->sg, sg, qc->n_elem, si) xfer += sg->length; - } task->total_xfer_len = xfer; - task->num_scatter = num; + task->num_scatter = si; } task->data_dir = qc->dma_dir; - task->scatter = qc->__sg; + task->scatter = qc->sg; task->ata_task.retry_count = 1; task->task_state_flags = SAS_TASK_STATE_PENDING; qc->lldd_task = task; |