Commit 6fe8c1db authored by Subhash Jadavani's avatar Subhash Jadavani Committed by Christoph Hellwig
Browse files

scsi: balance out autopm get/put calls in scsi_sysfs_add_sdev() 



SCSI Well-known logical units generally don't have any scsi driver
associated with it which means no one will call scsi_autopm_put_device()
on these wlun scsi devices and this would result in keeping the
corresponding scsi device always active (hence LLD can't be suspended as
well). Same exact problem can be seen for other scsi device representing
normal logical unit whose driver is yet to be loaded. This patch fixes
the above problem with this approach:

- make the scsi_autopm_put_device call at the end of scsi_sysfs_add_sdev
  to make it balance out the get earlier in the function.
- let drivers do paired get/put calls in their probe methods.

Signed-off-by: default avatarSubhash Jadavani <subhashj@codeaurora.org>
Signed-off-by: default avatarDolev Raviv <draviv@codeaurora.org>
Signed-off-by: default avatarChristoph Hellwig <hch@lst.de>
parent 50c4e964

drivers/scsi/scsi_sysfs.c

+1 −4
Original line number Diff line number Diff line
@@ -1044,10 +1044,6 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev) 
	pm_runtime_enable(&sdev->sdev_gendev);

	scsi_autopm_put_target(starget);



	/* The following call will keep sdev active indefinitely, until

	 * its driver does a corresponding scsi_autopm_pm_device().  Only

	 * drivers supporting autosuspend will do this.

	 */

	scsi_autopm_get_device(sdev);



	error = device_add(&sdev->sdev_gendev);
@@ -1085,6 +1081,7 @@ int scsi_sysfs_add_sdev(struct scsi_device *sdev) 
		}

	}



	scsi_autopm_put_device(sdev);

	return error;

}

drivers/scsi/sd.c

+2 −0
Original line number Diff line number Diff line
@@ -2965,6 +2965,7 @@ static int sd_probe(struct device *dev) 
	int index;

	int error;



	scsi_autopm_get_device(sdp);

	error = -ENODEV;

	if (sdp->type != TYPE_DISK && sdp->type != TYPE_MOD && sdp->type != TYPE_RBC)

		goto out;
@@ -3041,6 +3042,7 @@ static int sd_probe(struct device *dev) 
 out_free:

	kfree(sdkp);

 out:

	scsi_autopm_put_device(sdp);

	return error;

}

drivers/scsi/sr.c

+2 −0
Original line number Diff line number Diff line
@@ -657,6 +657,7 @@ static int sr_probe(struct device *dev) 
	struct scsi_cd *cd;

	int minor, error;



	scsi_autopm_get_device(sdev);

	error = -ENODEV;

	if (sdev->type != TYPE_ROM && sdev->type != TYPE_WORM)

		goto fail;
@@ -744,6 +745,7 @@ fail_put: 
fail_free:

	kfree(cd);

fail:

	scsi_autopm_put_device(sdev);

	return error;

}

drivers/scsi/st.c

+2 −0
Original line number Diff line number Diff line
@@ -4105,6 +4105,7 @@ static int st_probe(struct device *dev) 
		return -ENODEV;

	}



	scsi_autopm_get_device(SDp);

	i = queue_max_segments(SDp->request_queue);

	if (st_max_sg_segs < i)

		i = st_max_sg_segs;
@@ -4244,6 +4245,7 @@ out_put_disk: 
out_buffer_free:

	kfree(buffer);

out:

	scsi_autopm_put_device(SDp);

	return -ENODEV;

};

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