MFp4: Large set of CAM inprovements.

- Unify bus reset/probe sequence. Whenever bus attached at boot or later,
CAM will automatically reset and scan it. It allows to remove duplicate
code from many drivers.
- Any bus, attached before CAM completed it's boot-time initialization,
will equally join to the process, delaying boot if needed.
- New kern.cam.boot_delay loader tunable should help controllers that
are still unable to register their buses in time (such as slow USB/
PCCard/ CardBus devices), by adding one more event to wait on boot.
- To allow synchronization between different CAM levels, concept of
requests priorities was extended. Priorities now split between several
"run levels". Device can be freezed at specified level, allowing higher
priority requests to pass. For example, no payload requests allowed,
until PMP driver enable port. ATA XPT negotiate transfer parameters,
periph driver configure caching and so on.
- Frozen requests are no more counted by request allocation scheduler.
It fixes deadlocks, when frozen low priority payload requests occupying
slots, required by higher levels to manage theit execution.
- Two last changes were holding proper ATA reinitialization and error
recovery implementation. Now it is done: SATA controllers and Port
Multipliers now implement automatic hot-plug and should correctly
recover from timeouts and bus resets.
- Improve SCSI error recovery for devices on buses without automatic sense
reporting, such as ATAPI or USB. For example, it allows CAM to wait, while
CD drive loads disk, instead of immediately return error status.
- Decapitalize diagnostic messages and make them more readable and sensible.
- Teach PMP driver to limit maximum speed on fan-out ports.
- Make boot wait for PMP scan completes, and make rescan more reliable.
- Fix pass driver, to return CCB to user level in case of error.
- Increase number of retries in cd driver, as device may return several UAs.

1 files changed, 5 insertions, 2 deletions

diff --git a/sys/cam/cam_ccb.h b/sys/cam/cam_ccb.h
index 72de564..4c5adba 100644
--- a/sys/cam/cam_ccb.h
+++ b/sys/cam/cam_ccb.h
@@ -126,7 +126,7 @@ typedef enum {
 	XPT_PATH_INQ		= 0x04,
 				/* Path routing inquiry */
 	XPT_REL_SIMQ		= 0x05,
-				/* Release a frozen SIM queue */
+				/* Release a frozen device queue */
 	XPT_SASYNC_CB		= 0x06,
 				/* Set Asynchronous Callback Parameters */
 	XPT_SDEV_TYPE		= 0x07,
@@ -142,6 +142,8 @@ typedef enum {
 				/* Path statistics (error counts, etc.) */
 	XPT_GDEV_STATS		= 0x0c,
 				/* Device statistics (error counts, etc.) */
+	XPT_FREEZE_QUEUE	= 0x0d,
+				/* Freeze device queue */
 /* SCSI Control Functions: 0x10->0x1F */
 	XPT_ABORT		= 0x10,
 				/* Abort the specified CCB */
@@ -685,8 +687,9 @@ struct ccb_relsim {
 #define RELSIM_RELEASE_AFTER_TIMEOUT	0x02
 #define RELSIM_RELEASE_AFTER_CMDCMPLT	0x04
 #define RELSIM_RELEASE_AFTER_QEMPTY	0x08
+#define RELSIM_RELEASE_RUNLEVEL		0x10
 	u_int32_t      openings;
-	u_int32_t      release_timeout;
+	u_int32_t      release_timeout;	/* Abstract argument. */
 	u_int32_t      qfrozen_cnt;
 };