On 07/12/2014 06:48 PM, K. Y. Srinivasan wrote:
On Azure, we have seen instances of unbounded I/O latencies. To deal with this issue, implement handler that can reset the timeout. Note that the host gaurantees that it will respond to each command that has been issued.Signed-off-by: K. Y. Srinivasan <k...@microsoft.com> Cc: <sta...@vger.kernel.org> --- drivers/scsi/storvsc_drv.c | 10 ++++++++++ 1 files changed, 10 insertions(+), 0 deletions(-) diff --git a/drivers/scsi/storvsc_drv.c b/drivers/scsi/storvsc_drv.c index 7e8a642..3516761 100644 --- a/drivers/scsi/storvsc_drv.c +++ b/drivers/scsi/storvsc_drv.c @@ -33,6 +33,7 @@ #include <linux/device.h> #include <linux/hyperv.h> #include <linux/mempool.h> +#include <linux/blkdev.h> #include <scsi/scsi.h> #include <scsi/scsi_cmnd.h> #include <scsi/scsi_host.h> @@ -1518,6 +1519,14 @@ static int storvsc_host_reset_handler(struct scsi_cmnd *scmnd) return SUCCESS; } +static enum blk_eh_timer_return storvsc_timeout_handler(struct scsi_cmnd *scmnd) +{ + /* + * The host will respond; ask for more time. + */ + return BLK_EH_RESET_TIMER; +} + static bool storvsc_scsi_cmd_ok(struct scsi_cmnd *scmnd) { bool allowed = true; @@ -1697,6 +1706,7 @@ static struct scsi_host_template scsi_driver = { .bios_param = storvsc_get_chs, .queuecommand = storvsc_queuecommand, .eh_host_reset_handler = storvsc_host_reset_handler, + .eh_timed_out = storvsc_timeout_handler, .slave_alloc = storvsc_device_alloc, .slave_destroy = storvsc_device_destroy, .slave_configure = storvsc_device_configure,
Reviewed-by: Hannes Reinecke <h...@suse.de> Cheers, Hannes -- Dr. Hannes Reinecke zSeries & Storage h...@suse.de +49 911 74053 688 SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg GF: J. Hawn, J. Guild, F. Imendörffer, HRB 16746 (AG Nürnberg) -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
