diff options
| author | Salyzyn, Mark <mark_salyzyn@adaptec.com> | 2007-05-30 10:01:14 -0400 |
|---|---|---|
| committer | James Bottomley <jejb@mulgrave.il.steeleye.com> | 2007-06-01 11:39:56 -0400 |
| commit | 5c9cfeddbb49954b459fda91bf5479f5a0a4e409 (patch) | |
| tree | fd105c924eacc1bbc2e5d8da07b0a21eb919dd16 /drivers/scsi/aacraid/linit.c | |
| parent | 32fbac2256cedee62de5602b1703c15c150a6e14 (diff) | |
| download | lwn-5c9cfeddbb49954b459fda91bf5479f5a0a4e409.tar.gz lwn-5c9cfeddbb49954b459fda91bf5479f5a0a4e409.zip | |
[SCSI] aacraid: Changeable queue depth
Inspired by Brian King's patch to the ibmvscsi driver. Adds support for
a changeable queue depth to the aacraid driver.
Signed-off-by: Mark Salyzyn <aacraid@adaptec.com>
Signed-off-by: James Bottomley <James.Bottomley@SteelEye.com>
Diffstat (limited to 'drivers/scsi/aacraid/linit.c')
| -rw-r--r-- | drivers/scsi/aacraid/linit.c | 38 |
1 files changed, 38 insertions, 0 deletions
diff --git a/drivers/scsi/aacraid/linit.c b/drivers/scsi/aacraid/linit.c index a270a3f00647..6f92d077679f 100644 --- a/drivers/scsi/aacraid/linit.c +++ b/drivers/scsi/aacraid/linit.c @@ -446,6 +446,43 @@ static int aac_slave_configure(struct scsi_device *sdev) return 0; } +/** + * aac_change_queue_depth - alter queue depths + * @sdev: SCSI device we are considering + * @depth: desired queue depth + * + * Alters queue depths for target device based on the host adapter's + * total capacity and the queue depth supported by the target device. + */ + +static int aac_change_queue_depth(struct scsi_device *sdev, int depth) +{ + if (sdev->tagged_supported && (sdev->type == TYPE_DISK) && + (sdev_channel(sdev) == CONTAINER_CHANNEL)) { + struct scsi_device * dev; + struct Scsi_Host *host = sdev->host; + unsigned num = 0; + + __shost_for_each_device(dev, host) { + if (dev->tagged_supported && (dev->type == TYPE_DISK) && + (sdev_channel(dev) == CONTAINER_CHANNEL)) + ++num; + ++num; + } + if (num >= host->can_queue) + num = host->can_queue - 1; + if (depth > (host->can_queue - num)) + depth = host->can_queue - num; + if (depth > 256) + depth = 256; + else if (depth < 2) + depth = 2; + scsi_adjust_queue_depth(sdev, MSG_ORDERED_TAG, depth); + } else + scsi_adjust_queue_depth(sdev, 0, 1); + return sdev->queue_depth; +} + static int aac_ioctl(struct scsi_device *sdev, int cmd, void __user * arg) { struct aac_dev *dev = (struct aac_dev *)sdev->host->hostdata; @@ -844,6 +881,7 @@ static struct scsi_host_template aac_driver_template = { .bios_param = aac_biosparm, .shost_attrs = aac_attrs, .slave_configure = aac_slave_configure, + .change_queue_depth = aac_change_queue_depth, .eh_abort_handler = aac_eh_abort, .eh_host_reset_handler = aac_eh_reset, .can_queue = AAC_NUM_IO_FIB, |