ipr: Reboot speed improvements

Currently when performing a reboot with an ipr adapter,
the adapter gets shutdown completely, flushing all write
cache, as well as performing a full hardware reset of the card
during the shutdown phase of the old kernel. This ensures
the adapter is in a fully quiesced state across the reboot.

There are scenarios, however, such as when performing
kexec, where this full adapter shutdown is not required
and not desired, since it can make the reboot process take
noticeably longer.

This patch adds a module parameter to allow for skipping the
full shutdown during reboot. Rather than performing a full
adapter shutdown and reset, we simply cancel any outstanding
error buffers, place the adapter into a state where it has no
memory of any DMA addresses from the old kernel, then disable
the device. This significantly speeds up kexec boot, particularly
in configurations with multiple ipr adapters.

Signed-off-by: Brian King <brking@linux.vnet.ibm.com>
Reviewed-by: Wen Xiong <wenxiong@linux.vnet.ibm.com>
Reviewed-by: Daniel Kreling <kreling@linux.vnet.ibm.com>
Signed-off-by: James Bottomley <JBottomley@Odin.com>

1 files changed, 5 insertions, 1 deletions

diff --git a/drivers/scsi/ipr.h b/drivers/scsi/ipr.h
index ec03b42fa2b9..34eec5bcdce0 100644
--- a/drivers/scsi/ipr.h
+++ b/drivers/scsi/ipr.h
@@ -196,6 +196,8 @@
 /*
  * Adapter Commands
  */
+#define IPR_CANCEL_REQUEST                              0xC0
+#define IPR_CANCEL_64BIT_IOARCB                 0x01
 #define IPR_QUERY_RSRC_STATE                            0xC2
 #define IPR_RESET_DEVICE                                0xC3
 #define IPR_RESET_TYPE_SELECT                           0x80
@@ -222,6 +224,7 @@
 #define IPR_ABBREV_SHUTDOWN_TIMEOUT             (10 * HZ)
 #define IPR_DUAL_IOA_ABBR_SHUTDOWN_TO   (2 * 60 * HZ)
 #define IPR_DEVICE_RESET_TIMEOUT                (ipr_fastfail ? 10 * HZ : 30 * HZ)
+#define IPR_CANCEL_TIMEOUT                      (ipr_fastfail ? 10 * HZ : 30 * HZ)
 #define IPR_CANCEL_ALL_TIMEOUT          (ipr_fastfail ? 10 * HZ : 30 * HZ)
 #define IPR_ABORT_TASK_TIMEOUT          (ipr_fastfail ? 10 * HZ : 30 * HZ)
 #define IPR_INTERNAL_TIMEOUT                    (ipr_fastfail ? 10 * HZ : 30 * HZ)
@@ -1402,7 +1405,8 @@ enum ipr_shutdown_type {
         IPR_SHUTDOWN_NORMAL = 0x00,
         IPR_SHUTDOWN_PREPARE_FOR_NORMAL = 0x40,
         IPR_SHUTDOWN_ABBREV = 0x80,
-        IPR_SHUTDOWN_NONE = 0x100
+        IPR_SHUTDOWN_NONE = 0x100,
+        IPR_SHUTDOWN_QUIESCE = 0x101,
 };
 
 struct ipr_trace_entry {