[PATCH v3 15/19] scsi: Have sd pr_ops return a blk_status_t

[Mike Christie]

If a register or reserve hit a reservation conflict upper layers like LIO
need to pass that error to the initiator. To do this it has to know the
device/driver type so it can convert the return code because that's
currently a device/driver specific value. Instead of having the upper
layers figure out the device/driver type and call a driver specific
conversion function this has SCSI do the conversion and return a
blk_status_t which the upper layer knows how to handle. This will handle
the reservation conflict and in the future we can handle timeouts,
transport errors and sense errors if needed.

Signed-off-by: Mike Christie <michael.christie at oracle.com>
---
 drivers/scsi/sd.c | 28 +++++++++++++++++++---------
 1 file changed, 19 insertions(+), 9 deletions(-)

diff --git a/drivers/scsi/sd.c b/drivers/scsi/sd.c
index 8a39f25e4470..44d25194ff4e 100644
--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1696,7 +1696,8 @@ static int sd_get_unique_id(struct gendisk *disk, u8 id[16],
 }
 
 static int sd_pr_in_command(struct block_device *bdev, u8 sa,
-			    unsigned char *data, int data_len)
+			    unsigned char *data, int data_len,
+			    blk_status_t *blk_stat)
 {
 	struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
 	struct scsi_device *sdev = sdkp->device;
@@ -1732,6 +1733,9 @@ static int sd_pr_in_command(struct block_device *bdev, u8 sa,
 		scsi_print_sense_hdr(sdev, NULL, &sshdr);
 	}
 
+	if (blk_stat && result >= 0)
+		*blk_stat = scsi_result_to_blk_status(result);
+
 	return result;
 }
 
@@ -1746,7 +1750,7 @@ static int sd_pr_read_keys(struct block_device *bdev, struct pr_keys *keys_info,
 	if (!data)
 		return -ENOMEM;
 
-	result = sd_pr_in_command(bdev, READ_KEYS, data, data_len);
+	result = sd_pr_in_command(bdev, READ_KEYS, data, data_len, blk_stat);
 	if (result)
 		goto free_data;
 
@@ -1775,7 +1779,8 @@ static int sd_pr_read_reservation(struct block_device *bdev,
 	u8 data[24] = { 0, };
 	int result, len;
 
-	result = sd_pr_in_command(bdev, READ_RESERVATION, data, sizeof(data));
+	result = sd_pr_in_command(bdev, READ_RESERVATION, data, sizeof(data),
+				  blk_stat);
 	if (result)
 		return result;
 
@@ -1799,7 +1804,8 @@ static int sd_pr_read_reservation(struct block_device *bdev,
 }
 
 static int sd_pr_out_command(struct block_device *bdev, u8 sa, u64 key,
-		u64 sa_key, enum scsi_pr_type type, u8 flags)
+		u64 sa_key, enum scsi_pr_type type, u8 flags,
+		blk_status_t *blk_stat)
 {
 	struct scsi_disk *sdkp = scsi_disk(bdev->bd_disk);
 	struct scsi_device *sdev = sdkp->device;
@@ -1844,6 +1850,9 @@ static int sd_pr_out_command(struct block_device *bdev, u8 sa, u64 key,
 		scsi_print_sense_hdr(sdev, NULL, &sshdr);
 	}
 
+	if (blk_stat && result >= 0)
+		*blk_stat = scsi_result_to_blk_status(result);
+
 	return result;
 }
 
@@ -1854,7 +1863,8 @@ static int sd_pr_register(struct block_device *bdev, u64 old_key, u64 new_key,
 		return -EOPNOTSUPP;
 	return sd_pr_out_command(bdev, (flags & PR_FL_IGNORE_KEY) ? 0x06 : 0x00,
 			old_key, new_key, 0,
-			(1 << 0) /* APTPL */);
+			(1 << 0) /* APTPL */,
+			blk_stat);
 }
 
 static int sd_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type,
@@ -1863,27 +1873,27 @@ static int sd_pr_reserve(struct block_device *bdev, u64 key, enum pr_type type,
 	if (flags)
 		return -EOPNOTSUPP;
 	return sd_pr_out_command(bdev, 0x01, key, 0,
-				 block_pr_type_to_scsi(type), 0);
+				 block_pr_type_to_scsi(type), 0, blk_stat);
 }
 
 static int sd_pr_release(struct block_device *bdev, u64 key, enum pr_type type,
 		blk_status_t *blk_stat)
 {
 	return sd_pr_out_command(bdev, 0x02, key, 0,
-				 block_pr_type_to_scsi(type), 0);
+				 block_pr_type_to_scsi(type), 0, blk_stat);
 }
 
 static int sd_pr_preempt(struct block_device *bdev, u64 old_key, u64 new_key,
 		enum pr_type type, bool abort, blk_status_t *blk_stat)
 {
 	return sd_pr_out_command(bdev, abort ? 0x05 : 0x04, old_key, new_key,
-				 block_pr_type_to_scsi(type), 0);
+				 block_pr_type_to_scsi(type), 0, blk_stat);
 }
 
 static int sd_pr_clear(struct block_device *bdev, u64 key,
 		blk_status_t *blk_stat)
 {
-	return sd_pr_out_command(bdev, 0x03, key, 0, 0, 0);
+	return sd_pr_out_command(bdev, 0x03, key, 0, 0, 0, blk_stat);
 }
 
 static const struct pr_ops sd_pr_ops = {
-- 
2.25.1