Remove Giant from CAM. Drivers (SIMs) now register a mutex that CAM will

use to synchornize and protect all data objects that are used for that
SIM.  Drivers that are not yet MPSAFE register Giant and operate as
usual.  RIght now, no drivers are MPSAFE, though a few will be changed
in the coming week as this work settles down.

The driver API has changed, so all CAM drivers will need to be recompiled.
The userland API has not changed, so tools like camcontrol do not need to
be recompiled.

1 files changed, 19 insertions, 2 deletions

diff --git a/sys/cam/cam_sim.h b/sys/cam/cam_sim.h
index c4e3910..8976529 100644
--- a/sys/cam/cam_sim.h
+++ b/sys/cam/cam_sim.h
@@ -56,6 +56,7 @@ struct cam_sim *  cam_sim_alloc(sim_action_func sim_action,
 				const char *sim_name,
 				void *softc,
 				u_int32_t unit,
+				struct mtx *mtx,
 				int max_dev_transactions,
 				int max_tagged_dev_transactions,
 				struct cam_devq *queue);
@@ -90,17 +91,33 @@ struct cam_sim {
 	sim_poll_func		sim_poll;
 	const char		*sim_name;
 	void			*softc;
+	struct mtx		*mtx;
 	u_int32_t		path_id;/* The Boot device may set this to 0? */
 	u_int32_t		unit_number;
 	u_int32_t		bus_id;
 	int			max_tagged_dev_openings;
 	int			max_dev_openings;
 	u_int32_t		flags;
-#define		CAM_SIM_REL_TIMEOUT_PENDING	0x01
-	struct callout_handle	c_handle;
+#define	CAM_SIM_REL_TIMEOUT_PENDING	0x01
+#define	CAM_SIM_MPSAFE			0x02
+	struct callout		callout;
 	struct cam_devq 	*devq;	/* Device Queue to use for this SIM */
+
+	/* "Pool" of inactive ccbs managed by xpt_alloc_ccb and xpt_free_ccb */
+	SLIST_HEAD(,ccb_hdr)	ccb_freeq;
+	/*
+	 * Maximum size of ccb pool.  Modified as devices are added/removed
+	 * or have their * opening counts changed.
+	 */
+	u_int			max_ccbs;
+	/* Current count of allocated ccbs */
+	u_int			ccb_count;
+
 };
 
+#define CAM_SIM_LOCK(sim)	mtx_lock((sim)->mtx);
+#define CAM_SIM_UNLOCK(sim)	mtx_unlock((sim)->mtx);
+
 static __inline u_int32_t
 cam_sim_path(struct cam_sim *sim)
 {