target/sbc: Remove sbc_check_valid_sectors()

A similar check is performed at the end of sbc_parse_cdb() and is now
enforced if the SYNCHRONIZE CACHE command's backend supports
->execute_sync_cache().

(Add check_lba goto to avoid *_max_sectors checks - nab)

Signed-off-by: Christophe Vu-Brugier <cvubrugier@yahoo.fr>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_sbc.c

@@ -176,24 +176,6 @@ static inline u32 sbc_get_size(struct se_cmd *cmd, u32 sectors)
 	return cmd->se_dev->dev_attrib.block_size * sectors;
 }
 
-static int sbc_check_valid_sectors(struct se_cmd *cmd)
-{
-	struct se_device *dev = cmd->se_dev;
-	unsigned long long end_lba;
-	u32 sectors;
-
-	sectors = cmd->data_length / dev->dev_attrib.block_size;
-	end_lba = dev->transport->get_blocks(dev) + 1;
-
-	if (cmd->t_task_lba + sectors > end_lba) {
-		pr_err("target: lba %llu, sectors %u exceeds end lba %llu\n",
-			cmd->t_task_lba, sectors, end_lba);
-		return -EINVAL;
-	}
-
-	return 0;
-}
-
 static inline u32 transport_get_sectors_6(unsigned char *cdb)
 {
 	/*
@@ -877,15 +859,6 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 		break;
 	case SYNCHRONIZE_CACHE:
 	case SYNCHRONIZE_CACHE_16:
-		if (!ops->execute_sync_cache) {
-			size = 0;
-			cmd->execute_cmd = sbc_emulate_noop;
-			break;
-		}
-
-		/*
-		 * Extract LBA and range to be flushed for emulated SYNCHRONIZE_CACHE
-		 */
 		if (cdb[0] == SYNCHRONIZE_CACHE) {
 			sectors = transport_get_sectors_10(cdb);
 			cmd->t_task_lba = transport_lba_32(cdb);
@@ -893,18 +866,12 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 			sectors = transport_get_sectors_16(cdb);
 			cmd->t_task_lba = transport_lba_64(cdb);
 		}
-
-		size = sbc_get_size(cmd, sectors);
-
-		/*
-		 * Check to ensure that LBA + Range does not exceed past end of
-		 * device for IBLOCK and FILEIO ->do_sync_cache() backend calls
-		 */
-		if (cmd->t_task_lba || sectors) {
-			if (sbc_check_valid_sectors(cmd) < 0)
-				return TCM_ADDRESS_OUT_OF_RANGE;
+		if (ops->execute_sync_cache) {
+			cmd->execute_cmd = ops->execute_sync_cache;
+			goto check_lba;
 		}
-		cmd->execute_cmd = ops->execute_sync_cache;
+		size = 0;
+		cmd->execute_cmd = sbc_emulate_noop;
 		break;
 	case UNMAP:
 		if (!ops->execute_unmap)
@@ -988,7 +955,7 @@ sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops)
 				dev->dev_attrib.hw_max_sectors);
 			return TCM_INVALID_CDB_FIELD;
 		}
-
+check_lba:
 		end_lba = dev->transport->get_blocks(dev) + 1;
 		if (cmd->t_task_lba + sectors > end_lba) {
 			pr_err("cmd exceeds last lba %llu "