[PATCH 5/5] mtd: powernv_flash: Use opal_async_wait_response_interruptible()

[Cyril Bur <cyrilbur@gmail.com>]

The OPAL calls performed in this driver shouldn't be using
opal_async_wait_response() as this performs a wait_event() which, on
long running OPAL calls could result in hung task warnings. wait_event()
also prevents timely signal delivery which is also undesirable.

This patch also attempts to quieten down the use of dev_err() when
errors haven't actually occurred and also to return better information up
the stack rather than always -EIO.

Signed-off-by: Cyril Bur <cyrilbur@gmail.com>
---
 drivers/mtd/devices/powernv_flash.c | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/drivers/mtd/devices/powernv_flash.c b/drivers/mtd/devices/powernv_flash.c
index 7b41af06f4fe..a7c5ae2b2898 100644
--- a/drivers/mtd/devices/powernv_flash.c
+++ b/drivers/mtd/devices/powernv_flash.c
@@ -88,19 +88,23 @@ static int powernv_flash_async_op(struct mtd_info *mtd, enum flash_op op,
 	}
 
 	if (rc != OPAL_ASYNC_COMPLETION) {
-		dev_err(dev, "opal_flash_async_op(op=%d) failed (rc %d)\n",
-				op, rc);
+		if (rc != OPAL_BUSY)
+			dev_err(dev, "opal_flash_async_op(op=%d) failed (rc %d)\n",
+					op, rc);
 		opal_async_release_token(token);
-		rc = -EIO;
+		rc = opal_error_code(rc);
 		goto out;
 	}
 
-	rc = opal_async_wait_response(token, &msg);
+	rc = opal_async_wait_response_interruptible(token, &msg);
 	opal_async_release_token(token);
 	mutex_unlock(&info->lock);
 	if (rc) {
-		dev_err(dev, "opal async wait failed (rc %d)\n", rc);
-		return -EIO;
+		if (rc == -ERESTARTSYS)
+			rc = -EINTR;
+		else
+			dev_err(dev, "opal async wait failed (rc %d)\n", rc);
+		return rc;
 	}
 
 	rc = opal_get_async_rc(msg);
@@ -109,7 +113,7 @@ static int powernv_flash_async_op(struct mtd_info *mtd, enum flash_op op,
 		if (retlen)
 			*retlen = len;
 	} else {
-		rc = -EIO;
+		rc = opal_error_code(rc);
 	}
 
 	return rc;
-- 
2.13.2