scsi: add spdk_io_channel support

Signed-off-by: Jim Harris <james.r.harris@intel.com>
Change-Id: I189ea68c8550bbaeab79be36cb3c4faba7cd2f69

include/spdk/scsi.h

@@ -41,6 +41,7 @@
 
 #include <stdbool.h>
 #include <stdint.h>
+#include <pthread.h>
 #include <sys/uio.h>
 
 #include "spdk/queue.h"
@@ -193,6 +194,14 @@ struct spdk_scsi_lun {
 	/** The blockdev associated with this LUN. */
 	struct spdk_bdev *bdev;
 
+	/** I/O channel for the blockdev associated with this LUN. */
+	struct spdk_io_channel *io_channel;
+
+	/** Thread ID for the thread that allocated the I/O channel for this
+	 *   LUN.  All I/O to this LUN must be performed from this thread.
+	 */
+	pthread_t thread_id;
+
 	/** Name for this LUN. */
 	char name[SPDK_SCSI_LUN_MAX_NAME_LENGTH];
 
@@ -206,6 +215,8 @@ void spdk_scsi_dev_queue_task(struct spdk_scsi_dev *dev, struct spdk_scsi_task *
 int spdk_scsi_dev_add_port(struct spdk_scsi_dev *dev, uint64_t id, const char *name);
 struct spdk_scsi_port *spdk_scsi_dev_find_port_by_id(struct spdk_scsi_dev *dev, uint64_t id);
 void spdk_scsi_dev_print(struct spdk_scsi_dev *dev);
+int spdk_scsi_dev_allocate_io_channels(struct spdk_scsi_dev *dev);
+void spdk_scsi_dev_free_io_channels(struct spdk_scsi_dev *dev);
 
 /**
 

lib/scsi/dev.c

@@ -256,3 +256,34 @@ spdk_scsi_dev_print(struct spdk_scsi_dev *dev)
 	}
 }
 
+void
+spdk_scsi_dev_free_io_channels(struct spdk_scsi_dev *dev)
+{
+	int i;
+
+	for (i = 0; i < SPDK_SCSI_DEV_MAX_LUN; i++) {
+		if (dev->lun[i] == NULL) {
+			continue;
+		}
+		spdk_scsi_lun_free_io_channel(dev->lun[i]);
+	}
+}
+
+int
+spdk_scsi_dev_allocate_io_channels(struct spdk_scsi_dev *dev)
+{
+	int i, rc;
+
+	for (i = 0; i < SPDK_SCSI_DEV_MAX_LUN; i++) {
+		if (dev->lun[i] == NULL) {
+			continue;
+		}
+		rc = spdk_scsi_lun_allocate_io_channel(dev->lun[i]);
+		if (rc < 0) {
+			spdk_scsi_dev_free_io_channels(dev);
+			return -1;
+		}
+	}
+
+	return 0;
+}

lib/scsi/lun.c

@@ -34,6 +34,7 @@
 
 #include "scsi_internal.h"
 #include "spdk/endian.h"
+#include "spdk/io_channel.h"
 
 void
 spdk_scsi_lun_complete_task(struct spdk_scsi_lun *lun, struct spdk_scsi_task *task)
@@ -391,3 +392,29 @@ spdk_scsi_lun_delete(const char *lun_name)
 	spdk_scsi_lun_destruct(lun);
 	pthread_mutex_unlock(&g_spdk_scsi.mutex);
 }
+
+int spdk_scsi_lun_allocate_io_channel(struct spdk_scsi_lun *lun)
+{
+	if (lun->io_channel != NULL) {
+		if (pthread_self() == lun->thread_id) {
+			return 0;
+		}
+		SPDK_ERRLOG("io_channel already allocated for lun %s\n", lun->name);
+		return -1;
+	}
+
+	lun->io_channel = spdk_bdev_get_io_channel(lun->bdev, SPDK_IO_PRIORITY_DEFAULT);
+	if (lun->io_channel == NULL) {
+		return -1;
+	}
+	lun->thread_id = pthread_self();
+	return 0;
+}
+
+void spdk_scsi_lun_free_io_channel(struct spdk_scsi_lun *lun)
+{
+	if (lun->io_channel != NULL) {
+		spdk_put_io_channel(lun->io_channel);
+		lun->io_channel = NULL;
+	}
+}

lib/scsi/scsi_internal.h

@@ -85,6 +85,8 @@ int spdk_scsi_lun_claim(struct spdk_scsi_lun *lun);
 int spdk_scsi_lun_unclaim(struct spdk_scsi_lun *lun);
 int spdk_scsi_lun_deletable(const char *name);
 void spdk_scsi_lun_delete(const char *lun_name);
+int spdk_scsi_lun_allocate_io_channel(struct spdk_scsi_lun *lun);
+void spdk_scsi_lun_free_io_channel(struct spdk_scsi_lun *lun);
 
 int spdk_scsi_lun_db_add(struct spdk_scsi_lun *lun);
 int spdk_scsi_lun_db_delete(struct spdk_scsi_lun *lun);

test/lib/scsi/dev/dev_ut.c

@@ -117,6 +117,17 @@ spdk_scsi_lun_execute_tasks(struct spdk_scsi_lun *lun)
 {
 }
 
+int
+spdk_scsi_lun_allocate_io_channel(struct spdk_scsi_lun *lun)
+{
+	return 0;
+}
+
+void
+spdk_scsi_lun_free_io_channel(struct spdk_scsi_lun *lun)
+{
+}
+
 
 static void
 dev_destruct_null_dev(void)

test/lib/scsi/lun/lun_ut.c

@@ -140,7 +140,17 @@ spdk_bdev_scsi_execute(struct spdk_bdev *bdev, struct spdk_scsi_task *task)
 
 void spdk_bdev_unregister(struct spdk_bdev *bdev)
 {
-	return;
+}
+
+struct spdk_io_channel *
+spdk_bdev_get_io_channel(struct spdk_bdev *bdev, uint32_t priority)
+{
+	return NULL;
+}
+
+void
+spdk_put_io_channel(struct spdk_io_channel *ch)
+{
 }
 
 void spdk_event_call(spdk_event_t event)