PERFORCE change 116657 for review

[Scott Long]

http://perforce.freebsd.org/chv.cgi?CH=116657

Change 116657 by scottl at scottl-x64 on 2007/03/27 15:46:52

	Convert the CD driver to using callouts.  Lock the global list of
	changers.

Affected files ...

.. //depot/projects/scottl-camlock/src/sys/cam/scsi/scsi_cd.c#11 edit

Differences ...

==== //depot/projects/scottl-camlock/src/sys/cam/scsi/scsi_cd.c#11 (text+ko) ====

@@ -70,6 +70,7 @@
 #include <cam/cam_periph.h>
 #include <cam/cam_xpt_periph.h>
 #include <cam/cam_queue.h>
+#include <cam/cam_sim.h>
 
 #include <cam/scsi/scsi_message.h>
 #include <cam/scsi/scsi_da.h>
@@ -290,9 +291,6 @@
 
 PERIPHDRIVER_DECLARE(cd, cddriver);
 
-
-static int num_changers;
-
 #ifndef CHANGER_MIN_BUSY_SECONDS
 #define CHANGER_MIN_BUSY_SECONDS	5
 #endif
@@ -319,22 +317,26 @@
 	struct camq			 devq;
 	struct timeval			 start_time;
 	struct cd_softc			 *cur_device;
-	struct callout_handle		 short_handle;
-	struct callout_handle		 long_handle;
+	struct callout			 short_handle;
+	struct callout			 long_handle;
 	volatile cd_changer_flags	 flags;
 	STAILQ_ENTRY(cdchanger)		 changer_links;
 	STAILQ_HEAD(chdevlist, cd_softc) chluns;
 };
 
+static struct mtx changerq_mtx;
 static STAILQ_HEAD(changerlist, cdchanger) changerq;
+static int num_changers;
 
-
 static void
 cdinit(void)
 {
 	cam_status status;
 	struct cam_path *path;
 
+	mtx_init(&changerq_mtx, "cdchangerq", "SCSI CD Changer List", MTX_DEF);
+	STAILQ_INIT(&changerq);
+
 	/*
 	 * Install a global async callback.  This callback will
 	 * receive async callbacks like "new device found".
@@ -456,8 +458,7 @@
 		 * be any bogus pointer references there.
 		 */
 		if (softc->changer->flags & CHANGER_SHORT_TMOUT_SCHED) {
-			untimeout(cdshorttimeout, softc->changer,
-				  softc->changer->short_handle);
+			callout_stop(&softc->changer->short_handle);
 			softc->changer->flags &= ~CHANGER_SHORT_TMOUT_SCHED;
 		}
 		softc->changer->devq.qfrozen_cnt--;
@@ -478,22 +479,22 @@
 		 * it won't hurt to check and see if there are any left.
 		 */
 		if (softc->changer->flags & CHANGER_TIMEOUT_SCHED) {
-			untimeout(cdrunchangerqueue, softc->changer,
-				  softc->changer->long_handle);
+			callout_stop(&softc->changer->long_handle);
 			softc->changer->flags &= ~CHANGER_TIMEOUT_SCHED;
 		}
 
 		if (softc->changer->flags & CHANGER_SHORT_TMOUT_SCHED) {
-			untimeout(cdshorttimeout, softc->changer,
-				  softc->changer->short_handle);
+			callout_stop(&softc->changer->short_handle);
 			softc->changer->flags &= ~CHANGER_SHORT_TMOUT_SCHED;
 		}
 
+		mtx_lock(&changerq_mtx);
 		STAILQ_REMOVE(&changerq, softc->changer, cdchanger,
 			      changer_links);
+		num_changers--;
+		mtx_unlock(&changerq_mtx);
 		xpt_print(periph->path, "removing changer entry\n");
 		free(softc->changer, M_DEVBUF);
-		num_changers--;
 	}
 	disk_destroy(softc->disk);
 	free(softc, M_DEVBUF);
@@ -787,13 +788,11 @@
 		/* Set the changer flag in the current device's softc */
 		softc->flags |= CD_FLAG_CHANGER;
 
-		if (num_changers == 0)
-			STAILQ_INIT(&changerq);
-
 		/*
 		 * Now, look around for an existing changer device with the
 		 * same path and target ID as the current device.
 		 */
+		mtx_lock(&changerq_mtx);
 		for (found = 0,
 		     nchanger = (struct cdchanger *)STAILQ_FIRST(&changerq);
 		     nchanger != NULL;
@@ -804,6 +803,7 @@
 				break;
 			}
 		}
+		mtx_unlock(&changerq_mtx);
 
 		/*
 		 * If we found a matching entry, just add this device to
@@ -909,8 +909,6 @@
 				goto cdregisterexit;
 			}
 
-			num_changers++;
-
 			nchanger->path_id = cgd->ccb_h.path_id;
 			nchanger->target_id = cgd->ccb_h.target_id;
 
@@ -919,8 +917,16 @@
 
 			STAILQ_INIT(&nchanger->chluns);
 
+			callout_init_mtx(&nchanger->long_handle,
+			    periph->sim->mtx, 0);
+			callout_init_mtx(&nchanger->short_handle,
+			    periph->sim->mtx, 0);
+
+			mtx_lock(&changerq_mtx);
+			num_changers++;
 			STAILQ_INSERT_TAIL(&changerq, nchanger,
 					   changer_links);
+			mtx_unlock(&changerq_mtx);
 			
 			/*
 			 * Create a path with lun id 0, and see if we can
@@ -1186,9 +1192,9 @@
 			changer->cur_device->bufs_left = 
 				changer->cur_device->outstanding_cmds;
 			if (called_from_timeout) {
-				changer->long_handle =
-					timeout(cdrunchangerqueue, changer,
-				        changer_max_busy_seconds * hz);
+				callout_reset(&changer->long_handle,
+			            changer_max_busy_seconds * hz,
+				    cdrunchangerqueue, changer);
 				changer->flags |= CHANGER_TIMEOUT_SCHED;
 			}
 			splx(s);
@@ -1233,12 +1239,12 @@
 	 * ones so this device gets its full time quantum.
 	 */
 	if (changer->flags & CHANGER_TIMEOUT_SCHED) {
-		untimeout(cdrunchangerqueue, changer, changer->long_handle);
+		callout_stop(&changer->long_handle);
 		changer->flags &= ~CHANGER_TIMEOUT_SCHED;
 	}
 
 	if (changer->flags & CHANGER_SHORT_TMOUT_SCHED) {
-		untimeout(cdshorttimeout, changer, changer->short_handle);
+		callout_stop(&changer->short_handle);
 		changer->flags &= ~CHANGER_SHORT_TMOUT_SCHED;
 	}
 
@@ -1304,18 +1310,18 @@
 		 * and schedule our timeouts.
 		 */
 		if ((changer->flags & CHANGER_TIMEOUT_SCHED) == 0) {
-			changer->long_handle =
-			    timeout(cdrunchangerqueue, changer,
-				    changer_max_busy_seconds * hz);
+			callout_reset(&changer->long_handle,
+			    changer_max_busy_seconds * hz,
+			    cdrunchangerqueue, changer);
 			changer->flags |= CHANGER_TIMEOUT_SCHED;
 		} else
 			printf("cdchangerschedule: already have a long"
 			       " timeout!\n");
 
 		if ((changer->flags & CHANGER_SHORT_TMOUT_SCHED) == 0) {
-			changer->short_handle =
-			    timeout(cdshorttimeout, changer,
-				    changer_min_busy_seconds * hz);
+			callout_reset(&changer->short_handle,
+			    changer_min_busy_seconds * hz,
+			    cdshorttimeout, changer);
 			changer->flags |= CHANGER_SHORT_TMOUT_SCHED;
 		} else
 			printf("cdchangerschedule: already have a short "