X-Git-Url: http://ftp.safe.ca/?a=blobdiff_plain;f=include%2Fscsi%2Fscsi_tcq.h;h=17231385cb3721932bf02910854db0396d973b92;hb=d139b9bd0e52dda14fd13412e7096e68b56d0076;hp=bbf66219b7692393e20d94c49c76708022e42ecf;hpb=4aff5e2333c9a1609662f2091f55c3f6fffdad36;p=safe%2Fjmp%2Flinux-2.6

diff --git a/include/scsi/scsi_tcq.h b/include/scsi/scsi_tcq.h
index bbf6621..1723138 100644
--- a/include/scsi/scsi_tcq.h
+++ b/include/scsi/scsi_tcq.h
@@ -6,7 +6,6 @@
 #include <scsi/scsi_device.h>
 #include <scsi/scsi_host.h>
 
-
 #define MSG_SIMPLE_TAG	0x20
 #define MSG_HEAD_TAG	0x21
 #define MSG_ORDERED_TAG	0x22
@@ -14,6 +13,7 @@
 #define SCSI_NO_TAG	(-1)    /* identify no tag in use */
 
 
+#ifdef CONFIG_BLOCK
 
 /**
  * scsi_get_tag_type - get the type of tag the device supports
@@ -140,8 +140,39 @@ static inline struct scsi_cmnd *scsi_find_tag(struct scsi_device *sdev, int tag)
  */
 static inline int scsi_init_shared_tag_map(struct Scsi_Host *shost, int depth)
 {
-	shost->bqt = blk_init_tags(depth);
-	return shost->bqt ? 0 : -ENOMEM;
+	/*
+	 * If the shared tag map isn't already initialized, do it now.
+	 * This saves callers from having to check ->bqt when setting up
+	 * devices on the shared host (for libata)
+	 */
+	if (!shost->bqt) {
+		shost->bqt = blk_init_tags(depth);
+		if (!shost->bqt)
+			return -ENOMEM;
+	}
+
+	return 0;
+}
+
+/**
+ * scsi_host_find_tag - find the tagged command by host
+ * @shost:	pointer to scsi_host
+ * @tag:	tag of the scsi_cmnd
+ *
+ * Notes:
+ *	Only works with tags allocated by the generic blk layer.
+ **/
+static inline struct scsi_cmnd *scsi_host_find_tag(struct Scsi_Host *shost,
+						int tag)
+{
+	struct request *req;
+
+	if (tag != SCSI_NO_TAG) {
+		req = blk_map_queue_find_tag(shost->bqt, tag);
+		return req ? (struct scsi_cmnd *)req->special : NULL;
+	}
+	return NULL;
 }
 
+#endif /* CONFIG_BLOCK */
 #endif /* _SCSI_SCSI_TCQ_H */