On 07/22/2014 11:42 PM, Tejun Heo wrote:
Hello,
(cc'ing Dan)
On Tue, Jul 22, 2014 at 10:50:19AM -0400, Mike Qiu wrote:
The can_queue in scsi_host can be more than ATA_MAX_QUEUE (32),
for example, in ipr, it can be 100 or more.
Also, some drivers, like ipr driver, haven't filled the field
scsi_host in ata_port, and will lead a call trace, so add
check for that.
Signed-off-by: Mike Qiu <qiud...@linux.vnet.ibm.com>
---
drivers/ata/libata-core.c | 15 ++++-----------
1 file changed, 4 insertions(+), 11 deletions(-)
diff --git a/drivers/ata/libata-core.c b/drivers/ata/libata-core.c
index 259d879..a5b9c70 100644
--- a/drivers/ata/libata-core.c
+++ b/drivers/ata/libata-core.c
@@ -4734,7 +4734,10 @@ static struct ata_queued_cmd *ata_qc_new(struct ata_port
*ap)
struct ata_queued_cmd *qc = NULL;
unsigned int i, tag, max_queue;
- max_queue = ap->scsi_host->can_queue;
+ if (ap->scsi_host && ap->scsi_host->can_queue <= ATA_MAX_QUEUE)
+ max_queue = ap->scsi_host->can_queue;
+ else
+ max_queue = ATA_MAX_QUEUE;
/* no command while frozen */
if (unlikely(ap->pflags & ATA_PFLAG_FROZEN))
@@ -6109,16 +6112,6 @@ int ata_host_register(struct ata_host *host, struct
scsi_host_template *sht)
{
int i, rc;
- /*
- * The max queue supported by hardware must not be greater than
- * ATA_MAX_QUEUE.
- */
- if (sht->can_queue > ATA_MAX_QUEUE) {
- dev_err(host->dev, "BUG: the hardware max queue is too
large\n");
- WARN_ON(1);
- return -EINVAL;
- }
-
So, ummm, I really don't like that we're adding the conditionals to
the hot path (yeah, its implementation is slow but still). Maybe we
Yes, agree ..., not a good idea to do this...
Thanks
Mike
need to store the chosen queue depth after all? Dan?
Thanks.
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