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authorYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 12:17:53 -0700
committerYunhong Jiang <yunhong.jiang@intel.com>2015-08-04 15:44:42 -0700
commit9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (patch)
tree1c9cafbcd35f783a87880a10f85d1a060db1a563 /kernel/include/scsi/scsi_tcq.h
parent98260f3884f4a202f9ca5eabed40b1354c489b29 (diff)
Add the rt linux 4.1.3-rt3 as base
Import the rt linux 4.1.3-rt3 as OPNFV kvm base. It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and the base is: commit 0917f823c59692d751951bf5ea699a2d1e2f26a2 Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Date: Sat Jul 25 12:13:34 2015 +0200 Prepare v4.1.3-rt3 Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> We lose all the git history this way and it's not good. We should apply another opnfv project repo in future. Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423 Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>
Diffstat (limited to 'kernel/include/scsi/scsi_tcq.h')
-rw-r--r--kernel/include/scsi/scsi_tcq.h101
1 files changed, 101 insertions, 0 deletions
diff --git a/kernel/include/scsi/scsi_tcq.h b/kernel/include/scsi/scsi_tcq.h
new file mode 100644
index 000000000..b27977e8a
--- /dev/null
+++ b/kernel/include/scsi/scsi_tcq.h
@@ -0,0 +1,101 @@
+#ifndef _SCSI_SCSI_TCQ_H
+#define _SCSI_SCSI_TCQ_H
+
+#include <linux/blkdev.h>
+#include <scsi/scsi_cmnd.h>
+#include <scsi/scsi_device.h>
+#include <scsi/scsi_host.h>
+
+#define SCSI_NO_TAG (-1) /* identify no tag in use */
+
+
+#ifdef CONFIG_BLOCK
+static inline struct scsi_cmnd *scsi_mq_find_tag(struct Scsi_Host *shost,
+ int unique_tag)
+{
+ u16 hwq = blk_mq_unique_tag_to_hwq(unique_tag);
+ struct request *req = NULL;
+
+ if (hwq < shost->tag_set.nr_hw_queues)
+ req = blk_mq_tag_to_rq(shost->tag_set.tags[hwq],
+ blk_mq_unique_tag_to_tag(unique_tag));
+ return req ? (struct scsi_cmnd *)req->special : NULL;
+}
+
+/**
+ * scsi_find_tag - find a tagged command by device
+ * @SDpnt: pointer to the ScSI device
+ * @tag: tag generated by blk_mq_unique_tag()
+ *
+ * Notes:
+ * Only works with tags allocated by the generic blk layer.
+ **/
+static inline struct scsi_cmnd *scsi_find_tag(struct scsi_device *sdev, int tag)
+{
+ struct request *req;
+
+ if (tag != SCSI_NO_TAG) {
+ if (shost_use_blk_mq(sdev->host))
+ return scsi_mq_find_tag(sdev->host, tag);
+
+ req = blk_queue_find_tag(sdev->request_queue, tag);
+ return req ? (struct scsi_cmnd *)req->special : NULL;
+ }
+
+ /* single command, look in space */
+ return sdev->current_cmnd;
+}
+
+
+/**
+ * scsi_init_shared_tag_map - create a shared tag map
+ * @shost: the host to share the tag map among all devices
+ * @depth: the total depth of the map
+ */
+static inline int scsi_init_shared_tag_map(struct Scsi_Host *shost, int depth)
+{
+ /*
+ * We always have a shared tag map around when using blk-mq.
+ */
+ if (shost_use_blk_mq(shost))
+ return 0;
+
+ /*
+ * 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,
+ shost->hostt->tag_alloc_policy);
+ if (!shost->bqt)
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+/**
+ * scsi_host_find_tag - find the tagged command by host
+ * @shost: pointer to scsi_host
+ * @tag: tag generated by blk_mq_unique_tag()
+ *
+ * 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) {
+ if (shost_use_blk_mq(shost))
+ return scsi_mq_find_tag(shost, 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 */