target: Make spc_get_write_same_sectors return sector_t

We already expect TFO->get_blocks() to return sector_t for zero value case
when doing WRITE_SAME to the end of the backend device, so go ahead and return
sector_t from spc_get_write_same_sectors() to handle this case properly.

Also, update the single iblock_execute_write_same() caller of this code.

Cc: Christoph Hellwig <hch@lst.de>
Cc: Martin K. Petersen <martin.petersen@oracle.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>

drivers/target/target_core_iblock.c

@@ -481,7 +481,7 @@ iblock_execute_write_same(struct se_cmd *cmd)
 	struct bio *bio;
 	struct bio_list list;
 	sector_t block_lba = cmd->t_task_lba;
-	unsigned int sectors = spc_get_write_same_sectors(cmd);
+	sector_t sectors = spc_get_write_same_sectors(cmd);
 
 	sg = &cmd->t_data_sg[0];
 

drivers/target/target_core_sbc.c

@@ -107,7 +107,7 @@ sbc_emulate_readcapacity_16(struct se_cmd *cmd)
 	return 0;
 }
 
-int spc_get_write_same_sectors(struct se_cmd *cmd)
+sector_t spc_get_write_same_sectors(struct se_cmd *cmd)
 {
 	u32 num_blocks;
 

include/target/target_core_backend.h

@@ -52,7 +52,7 @@ void	target_complete_cmd(struct se_cmd *, u8);
 
 sense_reason_t	spc_parse_cdb(struct se_cmd *cmd, unsigned int *size);
 sense_reason_t	spc_emulate_report_luns(struct se_cmd *cmd);
-int	spc_get_write_same_sectors(struct se_cmd *cmd);
+sector_t	spc_get_write_same_sectors(struct se_cmd *cmd);
 
 sense_reason_t	sbc_parse_cdb(struct se_cmd *cmd, struct sbc_ops *ops);
 u32	sbc_get_device_rev(struct se_device *dev);