block: use symbolic constants for t10_pi type

Replace all hard-coded values with T10_PI_TYPES to make the code more
readable.

Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Max Gurtovoy <maxg@mellanox.com>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/block/t10-pi.c b/block/t10-pi.c
index 0c00946..7fed587 100644
--- a/block/t10-pi.c
+++ b/block/t10-pi.c
@@ -27,7 +27,7 @@ static __be16 t10_pi_ip_fn(void *data, unsigned int len)
  * tag.
  */
 static blk_status_t t10_pi_generate(struct blk_integrity_iter *iter,
-		csum_fn *fn, unsigned int type)
+		csum_fn *fn, enum t10_dif_type type)
 {
 	unsigned int i;
 
@@ -37,7 +37,7 @@ static blk_status_t t10_pi_generate(struct blk_integrity_iter *iter,
 		pi->guard_tag = fn(iter->data_buf, iter->interval);
 		pi->app_tag = 0;
 
-		if (type == 1)
+		if (type == T10_PI_TYPE1_PROTECTION)
 			pi->ref_tag = cpu_to_be32(lower_32_bits(iter->seed));
 		else
 			pi->ref_tag = 0;
@@ -51,7 +51,7 @@ static blk_status_t t10_pi_generate(struct blk_integrity_iter *iter,
 }
 
 static blk_status_t t10_pi_verify(struct blk_integrity_iter *iter,
-		csum_fn *fn, unsigned int type)
+		csum_fn *fn, enum t10_dif_type type)
 {
 	unsigned int i;
 
@@ -60,8 +60,8 @@ static blk_status_t t10_pi_verify(struct blk_integrity_iter *iter,
 		__be16 csum;
 
 		switch (type) {
-		case 1:
-		case 2:
+		case T10_PI_TYPE1_PROTECTION:
+		case T10_PI_TYPE2_PROTECTION:
 			if (pi->app_tag == T10_PI_APP_ESCAPE)
 				goto next;
 
@@ -74,7 +74,7 @@ static blk_status_t t10_pi_verify(struct blk_integrity_iter *iter,
 				return BLK_STS_PROTECTION;
 			}
 			break;
-		case 3:
+		case T10_PI_TYPE3_PROTECTION:
 			if (pi->app_tag == T10_PI_APP_ESCAPE &&
 			    pi->ref_tag == T10_PI_REF_ESCAPE)
 				goto next;
@@ -102,42 +102,42 @@ static blk_status_t t10_pi_verify(struct blk_integrity_iter *iter,
 
 static blk_status_t t10_pi_type1_generate_crc(struct blk_integrity_iter *iter)
 {
-	return t10_pi_generate(iter, t10_pi_crc_fn, 1);
+	return t10_pi_generate(iter, t10_pi_crc_fn, T10_PI_TYPE1_PROTECTION);
 }
 
 static blk_status_t t10_pi_type1_generate_ip(struct blk_integrity_iter *iter)
 {
-	return t10_pi_generate(iter, t10_pi_ip_fn, 1);
+	return t10_pi_generate(iter, t10_pi_ip_fn, T10_PI_TYPE1_PROTECTION);
 }
 
 static blk_status_t t10_pi_type1_verify_crc(struct blk_integrity_iter *iter)
 {
-	return t10_pi_verify(iter, t10_pi_crc_fn, 1);
+	return t10_pi_verify(iter, t10_pi_crc_fn, T10_PI_TYPE1_PROTECTION);
 }
 
 static blk_status_t t10_pi_type1_verify_ip(struct blk_integrity_iter *iter)
 {
-	return t10_pi_verify(iter, t10_pi_ip_fn, 1);
+	return t10_pi_verify(iter, t10_pi_ip_fn, T10_PI_TYPE1_PROTECTION);
 }
 
 static blk_status_t t10_pi_type3_generate_crc(struct blk_integrity_iter *iter)
 {
-	return t10_pi_generate(iter, t10_pi_crc_fn, 3);
+	return t10_pi_generate(iter, t10_pi_crc_fn, T10_PI_TYPE3_PROTECTION);
 }
 
 static blk_status_t t10_pi_type3_generate_ip(struct blk_integrity_iter *iter)
 {
-	return t10_pi_generate(iter, t10_pi_ip_fn, 3);
+	return t10_pi_generate(iter, t10_pi_ip_fn, T10_PI_TYPE3_PROTECTION);
 }
 
 static blk_status_t t10_pi_type3_verify_crc(struct blk_integrity_iter *iter)
 {
-	return t10_pi_verify(iter, t10_pi_crc_fn, 3);
+	return t10_pi_verify(iter, t10_pi_crc_fn, T10_PI_TYPE3_PROTECTION);
 }
 
 static blk_status_t t10_pi_type3_verify_ip(struct blk_integrity_iter *iter)
 {
-	return t10_pi_verify(iter, t10_pi_ip_fn, 3);
+	return t10_pi_verify(iter, t10_pi_ip_fn, T10_PI_TYPE3_PROTECTION);
 }
 
 const struct blk_integrity_profile t10_pi_type1_crc = {