diff mbox series

[v4,04/10] block: Move power management code into a new source file

Message ID 20180804000325.3610-5-bart.vanassche@wdc.com (mailing list archive)
State New, archived
Headers show
Series blk-mq: Enable runtime power management | expand

Commit Message

Bart Van Assche Aug. 4, 2018, 12:03 a.m. UTC
Move the code for runtime power management from blk-core.c into the
new source file blk-pm.c. Move the corresponding declarations from
<linux/blkdev.h> into <linux/blk-pm.h>. For CONFIG_PM=n, leave out
the declarations of the functions that are not used in that mode.
This patch not only reduces the number of #ifdefs in the block layer
core code but also reduces the size of header file <linux/blkdev.h>
and hence should help to reduce the build time of the Linux kernel
if CONFIG_PM is not defined.

Signed-off-by: Bart Van Assche <bart.vanassche@wdc.com>
Cc: Christoph Hellwig <hch@lst.de>
Cc: Jianchao Wang <jianchao.w.wang@oracle.com>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Johannes Thumshirn <jthumshirn@suse.de>
Cc: Alan Stern <stern@rowland.harvard.edu>
---
 block/Kconfig          |   5 ++
 block/Makefile         |   1 +
 block/blk-core.c       | 196 +----------------------------------------
 block/blk-pm.c         | 188 +++++++++++++++++++++++++++++++++++++++
 block/blk-pm.h         |  43 +++++++++
 block/elevator.c       |  22 +----
 drivers/scsi/scsi_pm.c |   1 +
 drivers/scsi/sd.c      |   1 +
 drivers/scsi/sr.c      |   1 +
 include/linux/blk-pm.h |  24 +++++
 include/linux/blkdev.h |  23 -----
 11 files changed, 266 insertions(+), 239 deletions(-)
 create mode 100644 block/blk-pm.c
 create mode 100644 block/blk-pm.h
 create mode 100644 include/linux/blk-pm.h

Comments

Christoph Hellwig Sept. 14, 2018, 1:01 p.m. UTC | #1
>  11 files changed, 266 insertions(+), 239 deletions(-)
>  create mode 100644 block/blk-pm.c
>  create mode 100644 block/blk-pm.h
>  create mode 100644 include/linux/blk-pm.h
> 
> diff --git a/block/Kconfig b/block/Kconfig
> index 1f2469a0123c..e213d90a5e64 100644
> --- a/block/Kconfig
> +++ b/block/Kconfig
> @@ -228,4 +228,9 @@ config BLK_MQ_RDMA
>  	depends on BLOCK && INFINIBAND
>  	default y
>  
> +config BLK_PM
> +	bool
> +	depends on BLOCK && PM
> +	default y

This could be shortened to

config BLK_PM
	def_bool BLOCK && PM

Also a lot of this code is only used by scsi.  I really wonder if
we should move it into scsi instead, and if not at least make it
a selectable option that only scsi selects.
Alan Stern Sept. 14, 2018, 2:10 p.m. UTC | #2
On Fri, 14 Sep 2018, Christoph Hellwig wrote:

> >  11 files changed, 266 insertions(+), 239 deletions(-)
> >  create mode 100644 block/blk-pm.c
> >  create mode 100644 block/blk-pm.h
> >  create mode 100644 include/linux/blk-pm.h
> > 
> > diff --git a/block/Kconfig b/block/Kconfig
> > index 1f2469a0123c..e213d90a5e64 100644
> > --- a/block/Kconfig
> > +++ b/block/Kconfig
> > @@ -228,4 +228,9 @@ config BLK_MQ_RDMA
> >  	depends on BLOCK && INFINIBAND
> >  	default y
> >  
> > +config BLK_PM
> > +	bool
> > +	depends on BLOCK && PM
> > +	default y
> 
> This could be shortened to
> 
> config BLK_PM
> 	def_bool BLOCK && PM
> 
> Also a lot of this code is only used by scsi.  I really wonder if
> we should move it into scsi instead, and if not at least make it
> a selectable option that only scsi selects.

Although SCSI is currently the only user of block-layer runtime PM, 
there's no reason other subsystems or drivers couldn't decide to use it 
too.  In theory, anything whose activity is controlled by block 
requests could benefit from it.

Making it selectable sounds like a reasonable approach.

Alan Stern
diff mbox series

Patch

diff --git a/block/Kconfig b/block/Kconfig
index 1f2469a0123c..e213d90a5e64 100644
--- a/block/Kconfig
+++ b/block/Kconfig
@@ -228,4 +228,9 @@  config BLK_MQ_RDMA
 	depends on BLOCK && INFINIBAND
 	default y
 
+config BLK_PM
+	bool
+	depends on BLOCK && PM
+	default y
+
 source block/Kconfig.iosched
diff --git a/block/Makefile b/block/Makefile
index 572b33f32c07..27eac600474f 100644
--- a/block/Makefile
+++ b/block/Makefile
@@ -37,3 +37,4 @@  obj-$(CONFIG_BLK_WBT)		+= blk-wbt.o
 obj-$(CONFIG_BLK_DEBUG_FS)	+= blk-mq-debugfs.o
 obj-$(CONFIG_BLK_DEBUG_FS_ZONED)+= blk-mq-debugfs-zoned.o
 obj-$(CONFIG_BLK_SED_OPAL)	+= sed-opal.o
+obj-$(CONFIG_BLK_PM)		+= blk-pm.o
diff --git a/block/blk-core.c b/block/blk-core.c
index 3a5aa56eab9d..03cff7445dee 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -42,6 +42,7 @@ 
 #include "blk.h"
 #include "blk-mq.h"
 #include "blk-mq-sched.h"
+#include "blk-pm.h"
 #include "blk-rq-qos.h"
 
 #ifdef CONFIG_DEBUG_FS
@@ -1720,16 +1721,6 @@  void part_round_stats(struct request_queue *q, int cpu, struct hd_struct *part)
 }
 EXPORT_SYMBOL_GPL(part_round_stats);
 
-#ifdef CONFIG_PM
-static void blk_pm_put_request(struct request *rq)
-{
-	if (rq->q->dev && !(rq->rq_flags & RQF_PM) && !--rq->q->nr_pending)
-		pm_runtime_mark_last_busy(rq->q->dev);
-}
-#else
-static inline void blk_pm_put_request(struct request *rq) {}
-#endif
-
 void __blk_put_request(struct request_queue *q, struct request *req)
 {
 	req_flags_t rq_flags = req->rq_flags;
@@ -3745,191 +3736,6 @@  void blk_finish_plug(struct blk_plug *plug)
 }
 EXPORT_SYMBOL(blk_finish_plug);
 
-#ifdef CONFIG_PM
-/**
- * blk_pm_runtime_init - Block layer runtime PM initialization routine
- * @q: the queue of the device
- * @dev: the device the queue belongs to
- *
- * Description:
- *    Initialize runtime-PM-related fields for @q and start auto suspend for
- *    @dev. Drivers that want to take advantage of request-based runtime PM
- *    should call this function after @dev has been initialized, and its
- *    request queue @q has been allocated, and runtime PM for it can not happen
- *    yet(either due to disabled/forbidden or its usage_count > 0). In most
- *    cases, driver should call this function before any I/O has taken place.
- *
- *    This function takes care of setting up using auto suspend for the device,
- *    the autosuspend delay is set to -1 to make runtime suspend impossible
- *    until an updated value is either set by user or by driver. Drivers do
- *    not need to touch other autosuspend settings.
- *
- *    The block layer runtime PM is request based, so only works for drivers
- *    that use request as their IO unit instead of those directly use bio's.
- */
-void blk_pm_runtime_init(struct request_queue *q, struct device *dev)
-{
-	/* Don't enable runtime PM for blk-mq until it is ready */
-	if (q->mq_ops) {
-		pm_runtime_disable(dev);
-		return;
-	}
-
-	q->dev = dev;
-	q->rpm_status = RPM_ACTIVE;
-	pm_runtime_set_autosuspend_delay(q->dev, -1);
-	pm_runtime_use_autosuspend(q->dev);
-}
-EXPORT_SYMBOL(blk_pm_runtime_init);
-
-/**
- * blk_pre_runtime_suspend - Pre runtime suspend check
- * @q: the queue of the device
- *
- * Description:
- *    This function will check if runtime suspend is allowed for the device
- *    by examining if there are any requests pending in the queue. If there
- *    are requests pending, the device can not be runtime suspended; otherwise,
- *    the queue's status will be updated to SUSPENDING and the driver can
- *    proceed to suspend the device.
- *
- *    For the not allowed case, we mark last busy for the device so that
- *    runtime PM core will try to autosuspend it some time later.
- *
- *    This function should be called near the start of the device's
- *    runtime_suspend callback.
- *
- * Return:
- *    0		- OK to runtime suspend the device
- *    -EBUSY	- Device should not be runtime suspended
- */
-int blk_pre_runtime_suspend(struct request_queue *q)
-{
-	int ret = 0;
-
-	if (!q->dev)
-		return ret;
-
-	spin_lock_irq(q->queue_lock);
-	if (q->nr_pending) {
-		ret = -EBUSY;
-		pm_runtime_mark_last_busy(q->dev);
-	} else {
-		q->rpm_status = RPM_SUSPENDING;
-	}
-	spin_unlock_irq(q->queue_lock);
-	return ret;
-}
-EXPORT_SYMBOL(blk_pre_runtime_suspend);
-
-/**
- * blk_post_runtime_suspend - Post runtime suspend processing
- * @q: the queue of the device
- * @err: return value of the device's runtime_suspend function
- *
- * Description:
- *    Update the queue's runtime status according to the return value of the
- *    device's runtime suspend function and mark last busy for the device so
- *    that PM core will try to auto suspend the device at a later time.
- *
- *    This function should be called near the end of the device's
- *    runtime_suspend callback.
- */
-void blk_post_runtime_suspend(struct request_queue *q, int err)
-{
-	if (!q->dev)
-		return;
-
-	spin_lock_irq(q->queue_lock);
-	if (!err) {
-		q->rpm_status = RPM_SUSPENDED;
-	} else {
-		q->rpm_status = RPM_ACTIVE;
-		pm_runtime_mark_last_busy(q->dev);
-	}
-	spin_unlock_irq(q->queue_lock);
-}
-EXPORT_SYMBOL(blk_post_runtime_suspend);
-
-/**
- * blk_pre_runtime_resume - Pre runtime resume processing
- * @q: the queue of the device
- *
- * Description:
- *    Update the queue's runtime status to RESUMING in preparation for the
- *    runtime resume of the device.
- *
- *    This function should be called near the start of the device's
- *    runtime_resume callback.
- */
-void blk_pre_runtime_resume(struct request_queue *q)
-{
-	if (!q->dev)
-		return;
-
-	spin_lock_irq(q->queue_lock);
-	q->rpm_status = RPM_RESUMING;
-	spin_unlock_irq(q->queue_lock);
-}
-EXPORT_SYMBOL(blk_pre_runtime_resume);
-
-/**
- * blk_post_runtime_resume - Post runtime resume processing
- * @q: the queue of the device
- * @err: return value of the device's runtime_resume function
- *
- * Description:
- *    Update the queue's runtime status according to the return value of the
- *    device's runtime_resume function. If it is successfully resumed, process
- *    the requests that are queued into the device's queue when it is resuming
- *    and then mark last busy and initiate autosuspend for it.
- *
- *    This function should be called near the end of the device's
- *    runtime_resume callback.
- */
-void blk_post_runtime_resume(struct request_queue *q, int err)
-{
-	if (!q->dev)
-		return;
-
-	spin_lock_irq(q->queue_lock);
-	if (!err) {
-		q->rpm_status = RPM_ACTIVE;
-		__blk_run_queue(q);
-		pm_runtime_mark_last_busy(q->dev);
-		pm_request_autosuspend(q->dev);
-	} else {
-		q->rpm_status = RPM_SUSPENDED;
-	}
-	spin_unlock_irq(q->queue_lock);
-}
-EXPORT_SYMBOL(blk_post_runtime_resume);
-
-/**
- * blk_set_runtime_active - Force runtime status of the queue to be active
- * @q: the queue of the device
- *
- * If the device is left runtime suspended during system suspend the resume
- * hook typically resumes the device and corrects runtime status
- * accordingly. However, that does not affect the queue runtime PM status
- * which is still "suspended". This prevents processing requests from the
- * queue.
- *
- * This function can be used in driver's resume hook to correct queue
- * runtime PM status and re-enable peeking requests from the queue. It
- * should be called before first request is added to the queue.
- */
-void blk_set_runtime_active(struct request_queue *q)
-{
-	spin_lock_irq(q->queue_lock);
-	q->rpm_status = RPM_ACTIVE;
-	pm_runtime_mark_last_busy(q->dev);
-	pm_request_autosuspend(q->dev);
-	spin_unlock_irq(q->queue_lock);
-}
-EXPORT_SYMBOL(blk_set_runtime_active);
-#endif
-
 int __init blk_dev_init(void)
 {
 	BUILD_BUG_ON(REQ_OP_LAST >= (1 << REQ_OP_BITS));
diff --git a/block/blk-pm.c b/block/blk-pm.c
new file mode 100644
index 000000000000..9b636960d285
--- /dev/null
+++ b/block/blk-pm.c
@@ -0,0 +1,188 @@ 
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/blk-pm.h>
+#include <linux/blkdev.h>
+#include <linux/pm_runtime.h>
+
+/**
+ * blk_pm_runtime_init - Block layer runtime PM initialization routine
+ * @q: the queue of the device
+ * @dev: the device the queue belongs to
+ *
+ * Description:
+ *    Initialize runtime-PM-related fields for @q and start auto suspend for
+ *    @dev. Drivers that want to take advantage of request-based runtime PM
+ *    should call this function after @dev has been initialized, and its
+ *    request queue @q has been allocated, and runtime PM for it can not happen
+ *    yet(either due to disabled/forbidden or its usage_count > 0). In most
+ *    cases, driver should call this function before any I/O has taken place.
+ *
+ *    This function takes care of setting up using auto suspend for the device,
+ *    the autosuspend delay is set to -1 to make runtime suspend impossible
+ *    until an updated value is either set by user or by driver. Drivers do
+ *    not need to touch other autosuspend settings.
+ *
+ *    The block layer runtime PM is request based, so only works for drivers
+ *    that use request as their IO unit instead of those directly use bio's.
+ */
+void blk_pm_runtime_init(struct request_queue *q, struct device *dev)
+{
+	/* Don't enable runtime PM for blk-mq until it is ready */
+	if (q->mq_ops) {
+		pm_runtime_disable(dev);
+		return;
+	}
+
+	q->dev = dev;
+	q->rpm_status = RPM_ACTIVE;
+	pm_runtime_set_autosuspend_delay(q->dev, -1);
+	pm_runtime_use_autosuspend(q->dev);
+}
+EXPORT_SYMBOL(blk_pm_runtime_init);
+
+/**
+ * blk_pre_runtime_suspend - Pre runtime suspend check
+ * @q: the queue of the device
+ *
+ * Description:
+ *    This function will check if runtime suspend is allowed for the device
+ *    by examining if there are any requests pending in the queue. If there
+ *    are requests pending, the device can not be runtime suspended; otherwise,
+ *    the queue's status will be updated to SUSPENDING and the driver can
+ *    proceed to suspend the device.
+ *
+ *    For the not allowed case, we mark last busy for the device so that
+ *    runtime PM core will try to autosuspend it some time later.
+ *
+ *    This function should be called near the start of the device's
+ *    runtime_suspend callback.
+ *
+ * Return:
+ *    0		- OK to runtime suspend the device
+ *    -EBUSY	- Device should not be runtime suspended
+ */
+int blk_pre_runtime_suspend(struct request_queue *q)
+{
+	int ret = 0;
+
+	if (!q->dev)
+		return ret;
+
+	spin_lock_irq(q->queue_lock);
+	if (q->nr_pending) {
+		ret = -EBUSY;
+		pm_runtime_mark_last_busy(q->dev);
+	} else {
+		q->rpm_status = RPM_SUSPENDING;
+	}
+	spin_unlock_irq(q->queue_lock);
+	return ret;
+}
+EXPORT_SYMBOL(blk_pre_runtime_suspend);
+
+/**
+ * blk_post_runtime_suspend - Post runtime suspend processing
+ * @q: the queue of the device
+ * @err: return value of the device's runtime_suspend function
+ *
+ * Description:
+ *    Update the queue's runtime status according to the return value of the
+ *    device's runtime suspend function and mark last busy for the device so
+ *    that PM core will try to auto suspend the device at a later time.
+ *
+ *    This function should be called near the end of the device's
+ *    runtime_suspend callback.
+ */
+void blk_post_runtime_suspend(struct request_queue *q, int err)
+{
+	if (!q->dev)
+		return;
+
+	spin_lock_irq(q->queue_lock);
+	if (!err) {
+		q->rpm_status = RPM_SUSPENDED;
+	} else {
+		q->rpm_status = RPM_ACTIVE;
+		pm_runtime_mark_last_busy(q->dev);
+	}
+	spin_unlock_irq(q->queue_lock);
+}
+EXPORT_SYMBOL(blk_post_runtime_suspend);
+
+/**
+ * blk_pre_runtime_resume - Pre runtime resume processing
+ * @q: the queue of the device
+ *
+ * Description:
+ *    Update the queue's runtime status to RESUMING in preparation for the
+ *    runtime resume of the device.
+ *
+ *    This function should be called near the start of the device's
+ *    runtime_resume callback.
+ */
+void blk_pre_runtime_resume(struct request_queue *q)
+{
+	if (!q->dev)
+		return;
+
+	spin_lock_irq(q->queue_lock);
+	q->rpm_status = RPM_RESUMING;
+	spin_unlock_irq(q->queue_lock);
+}
+EXPORT_SYMBOL(blk_pre_runtime_resume);
+
+/**
+ * blk_post_runtime_resume - Post runtime resume processing
+ * @q: the queue of the device
+ * @err: return value of the device's runtime_resume function
+ *
+ * Description:
+ *    Update the queue's runtime status according to the return value of the
+ *    device's runtime_resume function. If it is successfully resumed, process
+ *    the requests that are queued into the device's queue when it is resuming
+ *    and then mark last busy and initiate autosuspend for it.
+ *
+ *    This function should be called near the end of the device's
+ *    runtime_resume callback.
+ */
+void blk_post_runtime_resume(struct request_queue *q, int err)
+{
+	if (!q->dev)
+		return;
+
+	spin_lock_irq(q->queue_lock);
+	if (!err) {
+		q->rpm_status = RPM_ACTIVE;
+		__blk_run_queue(q);
+		pm_runtime_mark_last_busy(q->dev);
+		pm_request_autosuspend(q->dev);
+	} else {
+		q->rpm_status = RPM_SUSPENDED;
+	}
+	spin_unlock_irq(q->queue_lock);
+}
+EXPORT_SYMBOL(blk_post_runtime_resume);
+
+/**
+ * blk_set_runtime_active - Force runtime status of the queue to be active
+ * @q: the queue of the device
+ *
+ * If the device is left runtime suspended during system suspend the resume
+ * hook typically resumes the device and corrects runtime status
+ * accordingly. However, that does not affect the queue runtime PM status
+ * which is still "suspended". This prevents processing requests from the
+ * queue.
+ *
+ * This function can be used in driver's resume hook to correct queue
+ * runtime PM status and re-enable peeking requests from the queue. It
+ * should be called before first request is added to the queue.
+ */
+void blk_set_runtime_active(struct request_queue *q)
+{
+	spin_lock_irq(q->queue_lock);
+	q->rpm_status = RPM_ACTIVE;
+	pm_runtime_mark_last_busy(q->dev);
+	pm_request_autosuspend(q->dev);
+	spin_unlock_irq(q->queue_lock);
+}
+EXPORT_SYMBOL(blk_set_runtime_active);
diff --git a/block/blk-pm.h b/block/blk-pm.h
new file mode 100644
index 000000000000..1ffc8ef203ec
--- /dev/null
+++ b/block/blk-pm.h
@@ -0,0 +1,43 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _BLOCK_BLK_PM_H_
+#define _BLOCK_BLK_PM_H_
+
+#include <linux/pm_runtime.h>
+
+#ifdef CONFIG_PM
+static inline void blk_pm_requeue_request(struct request *rq)
+{
+	if (rq->q->dev && !(rq->rq_flags & RQF_PM))
+		rq->q->nr_pending--;
+}
+
+static inline void blk_pm_add_request(struct request_queue *q,
+				      struct request *rq)
+{
+	if (q->dev && !(rq->rq_flags & RQF_PM) && q->nr_pending++ == 0 &&
+	    (q->rpm_status == RPM_SUSPENDED || q->rpm_status == RPM_SUSPENDING))
+		pm_request_resume(q->dev);
+}
+
+static inline void blk_pm_put_request(struct request *rq)
+{
+	if (rq->q->dev && !(rq->rq_flags & RQF_PM) && !--rq->q->nr_pending)
+		pm_runtime_mark_last_busy(rq->q->dev);
+}
+#else
+static inline void blk_pm_requeue_request(struct request *rq)
+{
+}
+
+static inline void blk_pm_add_request(struct request_queue *q,
+				      struct request *rq)
+{
+}
+
+static inline void blk_pm_put_request(struct request *rq)
+{
+}
+#endif
+
+#endif /* _BLOCK_BLK_PM_H_ */
diff --git a/block/elevator.c b/block/elevator.c
index fa828b5bfd4b..4c15f0240c99 100644
--- a/block/elevator.c
+++ b/block/elevator.c
@@ -41,6 +41,7 @@ 
 
 #include "blk.h"
 #include "blk-mq-sched.h"
+#include "blk-pm.h"
 #include "blk-wbt.h"
 
 static DEFINE_SPINLOCK(elv_list_lock);
@@ -557,27 +558,6 @@  void elv_bio_merged(struct request_queue *q, struct request *rq,
 		e->type->ops.sq.elevator_bio_merged_fn(q, rq, bio);
 }
 
-#ifdef CONFIG_PM
-static void blk_pm_requeue_request(struct request *rq)
-{
-	if (rq->q->dev && !(rq->rq_flags & RQF_PM))
-		rq->q->nr_pending--;
-}
-
-static void blk_pm_add_request(struct request_queue *q, struct request *rq)
-{
-	if (q->dev && !(rq->rq_flags & RQF_PM) && q->nr_pending++ == 0 &&
-	    (q->rpm_status == RPM_SUSPENDED || q->rpm_status == RPM_SUSPENDING))
-		pm_request_resume(q->dev);
-}
-#else
-static inline void blk_pm_requeue_request(struct request *rq) {}
-static inline void blk_pm_add_request(struct request_queue *q,
-				      struct request *rq)
-{
-}
-#endif
-
 void elv_requeue_request(struct request_queue *q, struct request *rq)
 {
 	/*
diff --git a/drivers/scsi/scsi_pm.c b/drivers/scsi/scsi_pm.c
index b44c1bb687a2..a2b4179bfdf7 100644
--- a/drivers/scsi/scsi_pm.c
+++ b/drivers/scsi/scsi_pm.c
@@ -8,6 +8,7 @@ 
 #include <linux/pm_runtime.h>
 #include <linux/export.h>
 #include <linux/async.h>
+#include <linux/blk-pm.h>
 
 #include <scsi/scsi.h>
 #include <scsi/scsi_device.h>
diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index bbebdc3769b0..69ab459abb98 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -45,6 +45,7 @@ 
 #include <linux/init.h>
 #include <linux/blkdev.h>
 #include <linux/blkpg.h>
+#include <linux/blk-pm.h>
 #include <linux/delay.h>
 #include <linux/mutex.h>
 #include <linux/string_helpers.h>
diff --git a/drivers/scsi/sr.c b/drivers/scsi/sr.c
index 3f3cb72e0c0c..de4413e66eca 100644
--- a/drivers/scsi/sr.c
+++ b/drivers/scsi/sr.c
@@ -43,6 +43,7 @@ 
 #include <linux/interrupt.h>
 #include <linux/init.h>
 #include <linux/blkdev.h>
+#include <linux/blk-pm.h>
 #include <linux/mutex.h>
 #include <linux/slab.h>
 #include <linux/pm_runtime.h>
diff --git a/include/linux/blk-pm.h b/include/linux/blk-pm.h
new file mode 100644
index 000000000000..b80c65aba249
--- /dev/null
+++ b/include/linux/blk-pm.h
@@ -0,0 +1,24 @@ 
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef _BLK_PM_H_
+#define _BLK_PM_H_
+
+struct device;
+struct request_queue;
+
+/*
+ * block layer runtime pm functions
+ */
+#ifdef CONFIG_PM
+extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
+extern int blk_pre_runtime_suspend(struct request_queue *q);
+extern void blk_post_runtime_suspend(struct request_queue *q, int err);
+extern void blk_pre_runtime_resume(struct request_queue *q);
+extern void blk_post_runtime_resume(struct request_queue *q, int err);
+extern void blk_set_runtime_active(struct request_queue *q);
+#else
+static inline void blk_pm_runtime_init(struct request_queue *q,
+				       struct device *dev) {}
+#endif
+
+#endif /* _BLK_PM_H_ */
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index 1b3fe78872dc..2ef38739d645 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -1284,29 +1284,6 @@  struct request_queue *blk_alloc_queue_node(gfp_t gfp_mask, int node_id,
 extern void blk_put_queue(struct request_queue *);
 extern void blk_set_queue_dying(struct request_queue *);
 
-/*
- * block layer runtime pm functions
- */
-#ifdef CONFIG_PM
-extern void blk_pm_runtime_init(struct request_queue *q, struct device *dev);
-extern int blk_pre_runtime_suspend(struct request_queue *q);
-extern void blk_post_runtime_suspend(struct request_queue *q, int err);
-extern void blk_pre_runtime_resume(struct request_queue *q);
-extern void blk_post_runtime_resume(struct request_queue *q, int err);
-extern void blk_set_runtime_active(struct request_queue *q);
-#else
-static inline void blk_pm_runtime_init(struct request_queue *q,
-	struct device *dev) {}
-static inline int blk_pre_runtime_suspend(struct request_queue *q)
-{
-	return -ENOSYS;
-}
-static inline void blk_post_runtime_suspend(struct request_queue *q, int err) {}
-static inline void blk_pre_runtime_resume(struct request_queue *q) {}
-static inline void blk_post_runtime_resume(struct request_queue *q, int err) {}
-static inline void blk_set_runtime_active(struct request_queue *q) {}
-#endif
-
 /*
  * blk_plug permits building a queue of related requests by holding the I/O
  * fragments for a short period. This allows merging of sequential requests